• Korean Journal of Soil Science and Fertilizer
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• v.5 no.2
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• pp.39-42
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• 1972

A field experiment was conducted in a moderately well drained paddy field doveloped in a narrow strip of a valley in order to observe changes of potassium requirement in paddy production when lime is applied. The results obtained are as follows; 1. The response of paddy to potassium (K) and lime (L) is represented mathematically as follow; $Y=462.78+11.582K-0.058L-0.768K^2-0.000015L^2+0.2204KL$. It is considered that the increase of potassium reqirement when slaked lime is applied, is partially due to the increased growth of plant accomplished by the improvement of soil conditions such as the reduction of respiration inhibitors and cationic balance in soil solution. 2. An economic analysis of the use of potassium and slaked lime applying the costs, 80 won per kg of paddy, 19 won per kg of potassium and 4 won per kg of slaked lime to the response function above, showed that the slaked lime without potssium brought a large loss, whereas the use of the lime together with potassium increased the profit remarkably. The profit increased when 10kg of potassium per 10 a is applied in addition to 200kg slaked limn, per 10kg is amounted 4,685 won. 3. A linear relationship between the economic optimum dose of potassium (y) and the amount of slaked lime (x) in paddy production, is obtained as follow; $$y=7.48+\frac{2.77}{200}x$$ It is, however, considered that the amount of potassium to he used might differ according to the soil conditions such as the potassium content and cation exchange capicity of the soil.

• Korean Journal of Soil Science and Fertilizer
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• v.35 no.5
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• pp.296-305
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• 2002

Rice yield and grain guality were investigated with treatments of silicate fertilizer, straw compost and NPK fertilizer in the paddy soil of silty clay loam from 1975 to 2001. Rice yield of the treatments of silicate fertilizer. $1,500kg\;ha^{-1}$ and straw compost $10,00kg\;ha^{-1}$ were increased by 15%, 10%, respectively, for 27years average yield in comparison with NPK plot. In the plots of NPK+silicate fertilizer $1,500kg\;ha^{-1}$, NPK+silicate fertilizer $2,500kg\;ha^{-1}$, taste value(Toyo instrument) of cooked rice and quality assessment were higher than those in NPK control plot and NPK+straw compost $10,000kg\;ha^{-1}$ plot, but the contents of crude protein, amylose of milled rice grain were lower than those in other treated plots. Nitrogen and phosphorous contents of rice plant were lower, but $SiO_2$ content were higher in the treatment of silicate ferti lizer 1,500, $2,500kg\;ha^{-1}$ than straw compost $10,000kg\;ha^{-1}$ plot. Rice quality assessment was positively correlated with taste value, but it was negatively correlated with crude protein and amylose content of milled rice grain. Ratios of Mg/N, $Mg/N{\cdot}K_2O$, $SiO_2/N$, $SiO_2/P_2O_5$ and $SiO_2/K_2O$ were positively correlated with taste value and quality assessment of rice grain, but negatively correlated with crude protein, amylose and fatty acid content. In soil chemical characteristics related with rice quality after experiment in 2001, soil pH and $SiO_2$ content were positively correlated with taste value and quality assessment of rice grain, but contents of soil $P_2O_5$, ex-K were negatively correlated with them.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.2
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• pp.248-255
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• 2011

For the environmental friendly soil management on the cultivation of crops in the greenhouse, organic materials, such as the by product-fertilizer derived from livestock manure, rice straw, mushroom media, rice hulls, wood sawdust, and cocopeat, were used as carbon sources adjusting the ratio of carbon to nitrogen to 10, 20, and 30 based on the inorganic soil N. In each C/N ratio of greenhouse soil, watermelon was cultivated in the greenhouse as crop for experiment for the spring and summer of the year and the experimental results were summarized as follows. The concentration of T-C in the organic materials applied were between $289{\sim}429g\;kg^{-1}$, In the C/N ratio of 10, using watermelon as the crop cultivated during the second half of the year in the greenhouse soil, the $NO_3$-N and EC were reduced by 21 to 37%, and 26 to 33%, respectively, except the by product-fertilizer from livestock manure, compared to the soil $NO_3$-N and EC used in the experiment. After the watermelon was cultivated in soils that C/N ratios were controlled as 10, 20, and 30 with wood sawdust adding as carbon sources in the three soils with the different EC values, EC values of the soils were reduced by 33, 42, and 39%, respectively, compared to the soil EC used in the experiment. The weight of watermelon was 10.1-13.4 kg per one unit, and, of the three soils with different EC values. In the soils with three different EC values controlled at C/N ratio of 20, the weight of watermelon was good. The degree of sugar of watermelon were 11.8 to 12.3 Brix, which means that the difference between the treatments was not significant. In conclusion, the C/N ratio of 20 controlled by the proper supply of organic materials according to the representative EC values shown in the greenhouse soils was optimal condition enough to maintain the soil management for the organic culture with the proper nutrient cycling.

• Radiation Oncology Journal
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• v.17 no.1
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• pp.43-51
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• 1999

Purpose : To discuss the technical aspect of interstitial brachytherapy including method of implant, insertion time of radioactive source, total radiation dose, and complication, we reviewed patients who had diagnoses of soft tissue sarcoma and were treated by conservative surgery, interstitial implant and external beam radiation therapy Materials and Methods : Between May 1995 and Dec. 1997, ten patients with primary or recurrent soft tissue sarcoma underwent surgical resection (wide margin excision) and received radiotherapy including interstitial brachytherapy. Catheters were placed with regular intervals of 1 ~l.5 cm immediately after tumor removal and covering the critical structures, such as neurovascular bundle or bone, with gelform, muscle, or tissue expander in the cases where the tumors were close to those structures. Brachytherapy consisted of high dose rate, iridium-192 implant which delivered 12~15 Gy to 1 cm distance from the center of source axis with 2~2.5 Gy/fraction, twice a day, starting on 6th day after the surgery, Within one month after the surgery, total dose of 50~55 Gy was delivered to the tumor bed with wide margin by the external beam radiotherapy. Results : All patients completed planned interstitial brachytherapy without acute side effects directly related with catheter implantation such as infection or bleeding. With median follow up duration of 25 months (range 12~41 months), no local recurrences were observed. And there was no severe form of chronic complication (RTOGIEORTC grade 3 or 4). Conclusion : The high dose rate interstitial brachytherapy is easy and safe way to minimize the radiation dose delivered to the adjacent normal tissue and to decrease radiation induced chronic morbidity such as fibrosis by reducing the total dose of external radiotherapy in the management of soft tissue sarcoma with conservative surgery.

• Radiation Oncology Journal
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• v.21 no.1
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• pp.27-34
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• 2003

Purpose : To evaluate the efficacy of radiotherapy, and the factors affecting survival in patients of extrahepatic bile duct cancer, by analyzing the results of postoperative radiotherapy Materials and Methods : Between October 1991 and July 2001, 21 patients with extrahepatic bile duct cancer, who received radiotherapy after a radical resection, were retrospectively reviewed. The patients' ages ranged from 39 to 75 years, with a median of 61 years, and a male to female ratio of 16 to 5. The numbers of patients with proximal and distal bile duct cancer were 14 and 7, respectively. From the postoperative pathological examination, 19 of the patients were found to have microscopic residues, and 7 to be lymph node positive. Patients with AJCC stages I, II and III were 10, 10 and 1, respectively. The total radiation dose administered was 4,500$\~$6,300 cGy, with a median dose of 5,040 cGy. The follow up period was 20$\~$81 months, with a median of 57.5 months. Results : The overall and disease free survival rates at 3 and 5 years were 41.0 and 29.3$\%$, and 41.6 and 29.7$\%$, respectively. The influences of age, sex, tumor location, differentiation, microscopic residue, neural invasion, 7 and N stage, the stage itself, the dose of radiation and chemotherapy, on survival were evaluated. The T stage and the stage itself were found to be significant from a univariate analysis (p<0.05), but the degree of significance was limited by the small number of patients. A recurrence occurred in 12 patients (57.1$\%$), 5 in locoregional sites, 4 in distant sites and 3 in a combination of locoregional and distant sites, and the sites of distant metastasis were the liver, 6, and the bone, 1 Grade 2 or 3 acute leucopenias occurred in 2 patients and grade 2 chronic peptic ulcers occurred in 4, who were all recovered by conservative management. Conclusion : Postoperative radiotherapy is feasigbls in extrah데atic bile duct cancer, with tolerable toxicity, but prospective studies, with a large patient enrollment, are needed for the evaluation of the effects of postoperative radiotherapy and the related prognostic factors.

• Korean Journal of Optics and Photonics
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• v.13 no.3
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• pp.197-203
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• 2002

The TiO$_2$ coating solutions were synthesized with different concentrations (T1-0.7N, T2-2.0N) of hydrochloric acid used as catalyst. and TiO$_2$ thin films were prepared by sol-gel dip coating. Their structural and optical properties were examined as a function of calcination temperature. XRD results showed that T1 thin films calcined at 400~80$0^{\circ}C$ had the anatase phase, while those calcined at 100$0^{\circ}C$ had the rutile phase. T2 thin films calcined at 40$0^{\circ}C$ and $600^{\circ}C$ had the anatase phase, with the rutile phase for calcination at 80$0^{\circ}C$. Crystallinity of T2 thin films was superior to that of T1 thin films. The crystallite size of TiO$_2$ thin films increased with increasing calcination temperature, and the crystallite size of anatase phase in T2 thin films was larger than that in T1 thin films, but the crystallite size of rutile phase in T2 thin films was smaller. The surface morphology of the films showed that the films were formed more densely in the rutile phase than in the anatase phase, this phenomenon appeared conspicuously in T2 thin films. The transmittance of the samples with thin films on quartz glass calcined at 100$0^{\circ}C$ was significantly reduced at wavelength range about 300-700 nm due to the increased absorption originating from the change of crystallite phase and composition of the films and the scattering effect originating from increasing crystallite size. The refractive index of TiO$_2$ thin films increased, and hence the film thickness as well as the porosity of TiO$_2$ thin films decreased with increasing calcination temperature. Furthermore, the refractive index of T2 thin films was higher than T1 thin films, and porosity of T2 films was lower.

• Food Science and Preservation
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• v.23 no.2
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• pp.145-154
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• 2016

This study investigated the possibility of usage of freeze-dried ingredients for the preparation of Nabak kimchi. The quality characteristics of Nabak kimchi using freeze-dried ingredients (radish, kimchi cabbage, green onion, garlic and ginger) were monitored during storage at $4^{\circ}C$. The initial pH of Nabak kimchi was 5.76~5.93, however, it decreased significantly over increasing storage periods (p<0.05). The titratable acidity of Nabak kimchi increased during storage, reaching 0.43~1.08%. Among the freeze-dried samples, those treated with freeze-dried radish and minor ingredients showed lower titratable acidity than that of the control. The initial number of total aerobic and lactic acid bacteria were 5.57~6.25, and 5.52~6.24 log CFU/g, respectively. After 28 days, the population of total aerobic and lactic acid bacteria in the raw ingredients and freeze-dried minor ingredients was less than 8.0 log CFU/g, but more than 9.0 log CFU/g in other samples. Yeasts and molds in Nabak kimchi were detected up to 2~3 log CFU/g, but coliforms were not detected in all samples during storage. The score of firmness and overall acceptability in the control, raw ingredients and freeze-dried minor ingredients were significantly higher than others (p<0.05). These results indicated that freeze-dried ingredients, such as green onion, garlic, and ginger, can be used in kimchi and would delay microbial growth and extend the shelf-life of kimchi without any deduction of sensory quality.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.4
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• pp.291-298
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• 2001

Seawater, sediment and biota in the Kwangyang Bay were analyzed by gas chromatography/quartz furnace atomic absorption spectroscopy (GC-QFAAS) to investigate concentrations and distribution pattern of butyltin compounds (TBT, DBT, MBT) during February, April and July, 1996, Marine biota analyzed were Tapes japcnicus and Crassostrea gigas. The concentrations of tributyltin (TBT) in seawater were in the range of ND-15.7 ng/L for the surface and ND-68.5 ng/L for the bottom. The highest concentration of TBT in seawater was detected in April for the both, surface and bottom water. The maximum value of $TBT_{(bottom)}/TBT_{(surface)}$, 3.6 in April showed the increased input of TBT from the surface water in April compared to February (2.1) and July (0.9). The concentrations of TBT in the sediment were in the range of ND-8.5 ng/g dry wt. The highest concentration of TBT in the sediment was measured in July, This result seems to attributed to the removal of TBT from water column via sorption onto particulate matters to the relatively undisturbed underlying sediment and increased input of TBT by increased fluxes of detritus of marine plankton after spring bloom, in July. The mean values of partitioning coefficient ($K_d$) of TBT between seawater and sediment were $3.0\times10^3$(February), $7.4\times10^3$(April) and $9.4\times10^3$(July). The concentrations of TBT in biosamples were in the range of ND-93.30 ng/g dru wt. (T. japonicus) and ND-138.53 ng/g dry wt. (C. gigas). The seasonal variation of TBT contents in biota was remarkable. The $K_d$ (biological concentration factor) was $7-41\times10^3$ for T. japonicus. and $5-34\times10^3$ for C. gigas. The measured TBT concentrations in seawater in the study area was sufficient to cause the imposex of shellfish and to retard the growth of aquatic organisms including oyster upon chronic exposure.

• Applied Biological Chemistry
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• v.23 no.1
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• pp.64-72
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• 1980

Industrial wastes from pulp and food plants were treated with microorganisms to clarify organic waste-water and to produce cells as animal feed, and results were summarized as follows. (1) Waste-water from pulp, beer, bread yeast, and ethanol distillation plants contained $1.4{\sim}1.5%$ of total sugar, $0.25{\sim}0.35%$ nitrogen, and biological oxygen demand (BOD) was $400{\sim}25,000$, chemical oxygen demand (COD), $500{\sim}28,000$, and pH, $3.8{\sim}7.0$. The BOD and COD were highest in waste-water from ethanol distillation plants among others. (2) Bacterial and yeast counts were $4{\times}10^4-1{\times}10^9,\;2{\times}10^2-7{\times}10^4/ml$ in waste-water. (3) Bacteria grew better in pulp waste and yeasts in beer, bread yeast, and ethanol distillation waste. (4) Saccharomyces cerevisiae SAFM 1008 and Candida curvata SAFM 70 were the most suitable microorganisms for clarification of ethanol distillation waste. (5) When liquid and solid waste from ethanol distillation were treated with microbial cellulase, xylanase, and pectinase, solid waste was reduced by 36%, soluble waste was increased, and recuding sugar content was increased by 1.3 times which provided better medium than untreated waste for cultivation of yeasts. (6) Optimum growth conditions of the two species of yeast in ethanol distillation waste were pH 5.0, $30^{\circ}C$, and addition of 0.2% of urea, 0.1% of $KH_2PO_4$ and 0.02% of $MgSO_4$. (7) Minimum number of yeast for proper propagation was $1.8{\times}10^5/ml$. (8) C. curvata70 was better than cerevisae for the production of yeast cells from ethanol distillation waste treated with microbial enzymes. (9) S. cerevisiae produced 16 g of dried cell per 1,000ml of ethanol distillation waste and reduced BOD by 46%. C. curvata produced 17.6g of dried cell and reduced BOD by 52% at the same condition. (10) Yeast cells produced from the ethanol distillation waste contained 46-52% protein indicating suitability as a protein source for animal feed.

• Journal of the Mineralogical Society of Korea
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• v.27 no.4
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• pp.301-310
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• 2014

To investigate the role of fault gauge in the behavior of heavy metals caused by the acid rock drainage in the area of pyrite-rich andesite, XRD, pH measurement, XRF, SEM-EDS, ICP, and sequential extraction method were used. Bed rock consists of quartz, pyrophyllite, pyrite, illite, and topaz, but the brown-colored fault gouge is composed of quartz, illite, chlorite, smectite, goethite, and cacoxenite. The mineral composition of bed rock suggests that it is heavily altered by hydrothermal activity. The concentrations of heavy metals in the bed rock are as follows, Zn > As > Cu > Pb > Cr > Ni > Cd, and those in fault gouge are As > Zn > Pb > Cr > Cu > Ni > Cd. The concentrations of the heavy metals in the fault gouge are generally higher than those in the bed rock, especially for Pb, As, and Cr, which were more than twice as those in the bed rock. It is believed that the difference in the amount of heavy metals between the bed rock and the fault gouge is mainly due to the existence of goethite which is the main mineral composition in the fault gouge and can play important role in sequestering these metals by coprecipitation and adsorption. The low pH, caused by oxidation of pyrite, also plays significant role in fixation of those metals. It is confirmed that the fractions of labile (step 1) and acid-soluble (step 2), which can be easily released into the environment, were higher in the bed rock. Those fractions were relatively low in fault gauge, suggesting that fault gauge can play important role as a sink of heavy metals to prevent those ones from being released in the area where the acid rock drainage can have an influence.