• Economic and Environmental Geology
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• v.34 no.1
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• pp.13-23
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• 2001

Bentonite layers are intercalated within the basal conglomerates in the Tertiary sedimentary basins of Kampo, Janggi and Pohang, southeastern Korea. Eighteen samples of the bentonites went through X-ray diffraction, scanning electron microscopy, heavy mineral analyses, chemical analyses and oxygen, hydrogen stable isotope analyses to define the mineralogical characters of the bentonites. Heavy minerals such as zircons, apatites, amphiboles and biotites separated from bentonites show clean and euhedral surfaces, which are the characteristic features of volcanic origin. But biotites from the Chunbook Conglomerate are found as altered and heavily broken flakes which implies longer transportation of these bentonites. $TiO_{2}/Al_{2}O_{3} ratios of <2 $\mu$m particle fractions (the Chunbook Conglomerate 0.031; Janggi 0.029; Kampo 0.025) suggest that those are originated from volcanic tuffs. That is, the higher the value is, the more mafic in chemical compositions of the original tuffs. Authigenic montmorillonite and zeolite minerals were observed by SEM, which indicates diagenesis origin of bentonites. But the samples from the Chunbook Conglomerate showed only chaotically packed clay flakes in the matrix of sands or conglomerates, which implies detrital influence, not authigenic origin. The structural formulae of montmorillonite from these basins reflects their environment of formation. Fe (Ⅵ) can show the redox condition of its past environment and much lower $Fe^{2+}(Ⅵ)/Fe^{3+}(Ⅵ)$ ratios in montmorillonite of the Chunbook Conglomerate imply the greater oxidizing influence. Calculated burial depths from oxygen stable isotope data of the samples from the Chunbook Conglomerate generally fall to the range of 929~963 m whereas the real burial depth of this area is only 530~580 m. This could be explained as the bentonites of the Chunbook conglomerate had not been formed in situ. Discriminant analyses with the data from chemical analyses and structural formulae of montmorillonites show that bentonites from three different basins could definitely be distinguished with each other. This result arises from the different chemical compositions of original volcanic ashes and the difference of sedimentary environments.

• Radiation Oncology Journal
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• v.20 no.2
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• pp.186-192
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• 2002

Purpose : Measurement of transmission dose is useful for in vivo dosimetry. In this study, previous algorithm for estimation of transmission dose was modified for use in cases with tissue deficit. Materials and Methods : The beam data was measured with flat solid phantom in various conditions of tissue deficit. New algorithm for correction of transmission dose for tissue deficit was developed by physical reasoning. The algorithm was tested in experimental settings with irregular contours mimicking breast cancer patients using multiple sheets of solid phantoms. Results : The correction algorithm for tissue deficit could accurately reflect the effect of tissue deficit with errors within ${\pm}1.0\%$ in most situations and within ${\pm}3.0\%$ in experimental settings with irregular contours mimicking breast cancer treatment set-up. Conclusion : Developed algorithm could accurately reflect the effect of tissue deficit and irregularly shaped body contour on transmission dosimetry.

• Korean Journal of Weed Science
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• v.32 no.2
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• pp.85-97
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• 2012

To investigate the usefulness of freshwater alga Water-net (Hydrodictyon reticulatum, HR) as resources for production of fermentable sugars, the easiness of enzymatic saccharification was evaluated at first. When 6 plant materials (HR, Spirulina, Chlorella, Scenedesmus, Cladophora, Corn stover) were enzymatically hydrolyzed with 2% solid loading at the same condition, HR showed the highest ratio of saccharification based on glucose production. No milled HR was also completely saccharified at the amounts of optimal enzyme mixture. Glucose yield was not changed though the citrate buffer strength for saccharification was decreased from 0.1 M to 0.1 mM. Only about 10% yield reduction was observed compared to that of $120^{\circ}C$ treatment when HR was enzymatically hydrolyzed at room temperature. The saccharification was normally occurred at $37^{\circ}C$ and pH 6.5 which is general growth condition of fermentable microrganisms, suggesting that HR have a biomass characteristics applicable for the simultaneous saccharification and fermentation. The saccharification was occurred by more than 70~80% of one of the best condition although the supplied enzyme amounts was reduced to 1/10 volume. And the glucose yield by enzymatic hydrolysis was not decreased by 10% HR solid loading and began to decrease at more than 15% solid contents. Above these results show that HR is an interesting algal biomass which is relatively easy to be saccharified by hydrolyzing enzymes. In addition, HR is a flilamentous alga and very easy to be collected. Therefore, HR seems to be an useful and valuable resources in the economical production of fermentable sugars for manufacture of bio-chemical products.

• Journal of Korean Society of Forest Science
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• v.58 no.1
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• pp.41-47
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• 1982

The large devastated land in Young-il district, Gyeongsangbusdo, had been existed for a long time, and the Korean government had invested 3.8 billion won to control soil erosion of the area for 5 years from 1973 to 1977. This research was to investigate the changes of the soil profile and vegetation structure in the 3rd, 6th and 9th years since soil erosion control had implemented. The results obtained in this study are as follows: 1) The thickness of the litter layer (L), the fermentation layer(F), the humified layer(H) and the surface soil layer(S) increased with increasing years after implements soil erosion control project had started. 2) The H layer was not showed for the three years since the project had implemented but was in the sixty year. 3) The soil chemical elements including the organic matter and total nitrogen increased with increasing years after the project had started, the amounts of organic matter and total nitrogen were three and seven times higher respectively in the nineth year after project had started. The amounts of organic matter and total nitrogen were three and seven times higher, respectively in the nineth year after project started than those before. 4) Among the grasses and trees which had been sowed or planted during project period, the summed domination ratios for arundinella hirta var ciliare. Themeda japonica, Cymbopogen goeringi and Lespedeza bicolor decreased rapidly, while those for Robinia pesudoacacia and Pinus densiflora increased with increasing years after the project started. 5) The appearance of Quercus seedlings suited to this area and Pinus densiflora seedling which is a subclimax species increased with increasing years after the project started.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.4
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• pp.476-483
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• 2005

This experiment was planned to develop a functional supplement by food resources to prevent and lessen the deleterious effects caused by environmental pollutants such as polluted food, air, water and heavy metals. The goal of this study was to investigate the effects of peking-duck extracts supplemented with six kinds of medicinal herbs (DJ) on the intoxication of lead and mercury in rats. Sprague-Dawley rat weighing $150g\pm15g$ g, were randomly assigned to 5 groups, basal diet only (NCG), heavy metal without DJ injection (HCG), heavy metals and DJ (3 mg/mL) injection (HMLD), heavy metal and DJ (30 mg/mL) injection (HMMD), heavy metal and D] (300 mg/mL) injection (HMHD). Mecury (Hg) and lead (Pb) injected at the level of 50 ppm for 17 days. Also DJ oral feeding was continued for 31 days. The result of this study were as follows; Food intake and body weight gain in heavy metal administered groups were lower than those of control group (NCG). The activities of GOT, GPT and BUN level were significantly reduced in DJ-treated groups as compared to HCG. DJ was shown to suppress the accumulation of Hg and Pb in serum. The results suggest that DJ might have protective effect on Hg and Pb intoxication.

• The Korean Journal of Malacology
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• v.19 no.2
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• pp.161-169
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• 2003

Seawater and sediment quality analysed was calculated to examinate the present environmental characteristics and pollution load was also calculated to evaluate the effect of farming area on the coastal environment. The measurements for seawater quality demonstrate the coastal environment has relatively eutrophicated with significantly decreased DO (0.2-8.5 mg/l) and elevated COD (9.6-31.2 mg/l) in summer. It was also evident that the water quality in Jindong Bay has been influenced by residues tide from Masan Bay with high metal concentration in August of 2002. Annual total pollution load (land and farm-driven) was estimated at 37,316 ton (SS) /yr: 9,809 ton/yr (26.3%) of land-driven load, 23,576 ton/yr (63.2%) of coastal sedimentation and 3,932 ton/yr (10.5%) of feces of cultural organisms. When all ark shell seedling farms are permitted species conversion to ascidian farm, the pollution load would increase by 196%, which may be another source for accelerating the eutrophication of the environment in Jindong Bay.

• Korean Journal of Environmental Agriculture
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• v.13 no.1
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• pp.31-38
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• 1994

This study was carried out to investigate the possibility of potential injury to crops which were exposed to precipitation. The rainwater were collected from May to September in 1992 and analyzed its chemical composition. The amounts of chlorophyll and cations in plant were measured, and the morphological structure of epidermis was also investigated by SEM. The results are summarized as follows: 1. The pH of precipitation in Suwon was relatively high even with high level of $SO_4^{2-}$ and monthly pH at May, June, July, August, and September were 4.65, 5.47, 5.32, 5.44 and 4.80, respectively. 2. The amount of ions in rainwater was in the order of $NH_4^+$, $Ca^{2+}$, $Mg^{2+}$ and $H^+$ for cations, and $SO_4^{2-}$, $NO_3^-$ and $Cl^-$ for anions. 3. pH of rain in less than 5mm of precipitation was higher than that in greater than 5mm of precipitation. 4. The amount of chlorophyll was higher in the plant exposed to rain than that in plant intercepted rain during the early portion of growing season, but at the later period, the trend was shown to be reversed. 5. When the sesame plants were exposed to rain at harvesting stage, they contained less amount of CaO, MgO and $Na_2O$ than those with the interception of rain. 6. Scanning electron microphotographs revealed the shringkage in glandular trichomes in the epidermis of sesame leaves when they were exposed to rain.

• Journal of the Korea Organic Resources Recycling Association
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• v.2 no.2
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• pp.65-75
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• 1994

The aim of this experiment was to investigate the effects of applying time of cattle slurry and fertilizing added mineral nitrogen on dry matter yield of orchardgrass and also to estimate proper levels of fertilizing nitrogen when idled arable land rapidly increased these days, which was used for the production of Orchardgrass. The results were as follows. 1. The annual yields of dry matter were produced 5.62~6.67 ton per ha when cattle slurry applied at rates of $30m^3$(average mineral fertilizer equivalent to 120kg) per ha in different dressing times. Those were higher 0.60~1.65 ton or 0.16 ton per ha than the yields from non-fertilizing or phosphrous and potassium fertilizing. 2. Relative yields of annual dry matter from mineral nitrogen fertilization of 120kg per ha were 142~146% in comparsion with control plots(cattle slurry plot or phosphrous and potassium plot). On the other hand, those of cattle slurry application were 112~133% in comparion with non-fertilizing plot. 3. The efficiencies of nitrogen on dry matter yield(kg DM/kg N) were 5.0~13.8 DM kg/N kg when cattle slurry applied to Orchardgrass at rates of $30m^3$(average mineral fertilizer equivalent to 120kg) per ha, and were 21.3~23.1kg DM/kg N at the same level fertilization of mineral nitrogen. 4. On the condition of this study, mineral nitrogen were fertilized after applying cattle slurry at rates of $30m^3$(average mineral fertilizer equivalent to 120kg) per ha in order to minimize chemical fertilizer and increase the potential production of Orchardgrass. At this situation, marginal dry matter yields of 8.48~8.63 ton per ha were obtained as the level of economic even point goint when mineral nitrogen fertilization is between 119.4 and 133.3kg per ha. It was possible to obtain the maximal dry matter yield(8.98 tons/ha) with fertilization of 202.8kg N/ha.

• Proceedings of the Korean Society of Organic Agriculture Conference
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• 2009.12a
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• pp.275-276
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• 2009

민간단체들에 의하여 자율적으로 시작된 국내 유기농업은 친환경농업육성법(1997. 12.13)이 제정되면서 국가기관의 친환경농업 활성화 노력과 더불어 2008년 유기농재배 농가(8,460호)와 면적(12,033호)이 급격히 증가되었다. 또한 유기농업의 확산과 더불어 화학비료 및 유기합성 농약대체 친환경농자재들의 유통이 증가되고 있으나 관리규정이 없어 검증되지 않은 다양한 농자재들이 유통되어 친환경실천 농가들의 혼란이 초래되어 국정감사 시 문제점으로 지적과 함께 각계에서 관리제도의 필요성이 대두되었다. 친환경농업육성법 시행령 개정(대통령령 제19964호, 2007.3.27.공포, 2007.3.28.시행)으로 농촌진흥청에 친환경농자재심의회가 설치되어 효과와 효능을 검증하지 아니하고 친환경농산물 중 유기농산물 생을 해 사용가능한 자재인지 여부를 검토하여 그 결과를 공개하는 목록공시제가 마련되었다. 친환경유기농자재 목록공시는 1년에 4회 매분기말에 농촌진흥청 농자재관리과에서 접수를 받아 친환경농자재 분야별 전문위원회 검토 후 심의위원회 심의를 거쳐 접수일로부터 90일 이내에 농촌진흥청장이 공시(농진청 홈페이지, 관보게재)하고 친환경농업 관련기관 및 검토 신청자에게 통보함으로서 마무리된다. 목록 공시된 친환경유기농자재의 유효기간은 2년이다. 친환경농자재심의위원회는 토양개량 및 작물생육분야 전문위원회 위원 11명, 병 해충 관리분야 전문위원회 위원 11명 및 심의위원회 의원 20명으로 구성되어 있다. 2007년 3월부터 2009년 11월 30일 현재 목록 공시된 친환경유기농자재 제품은 (1) 양개량용 자재 25 개, (2) 작물생육용 자재 282개, (3) 토양개량 및 작물생육용 자재 308개, (4) 작물병해 관리용 자재 110개, (5) 작물충해 관리용 자재 : 224개, (6) 작물병해충 관리용 자재 5개 및 (7) 기타 자재 1개 제품으로 총 955개 제품에 이르고 있다. 한편, 공시연장 미신청, 현재 검토기준안에 필요로 하는 추가요청 자료 미제출 및 공시이외의 물질 사용으로 국내유통 중 단속되어 부적합한 판정을 받아 20여 제품이 목록공시가 취소되었다. 앞으로 목록 공시되는 친환경유기농자재는 제품의 주성분 함량 표기, 시용효과 검정방법 선, 제조방법 현장점검, 안전성 검정 등 여러가지 제도보완 및 사후관리 방안이 시급히 마련되어야 할 것으로 사려된다.

• Journal of Life Science
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• v.18 no.6
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• pp.789-795
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• 2008

To study the possible use of probiotics in fish farming, we evaluated antagonism of antibacterial strain Bacillus amyloliquefaciens H41 against the fish pathogenic bacterium Vibrio anguillarum NCMB1. The purification of growth inhibition factor produced by B. amyloliquefaciens H41 was achieved by obtaining supernatant of this bacterium. The growth inhibition factor was purified to homogeneity by 70% ammonium sulfate precipitation, DEAE-sephadex A-50 ion exchange chromatography, sephadex G-200 gel filtration column chromatography, and sephadex G-50 gel filtration column chromatography with 40.8 fold of purification and 2.9% yield. The molecular weight of the purified growth inhibition factor was 48 kDa as determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The optimum pH and temperature for the growth inhibition factor were pH 7.5 and $30^{\circ}C$, respectively. The activity of growth inhibition factor was enhanced slightly by some metal ions, such as $Mg^{+2}$, $Mn^{+2}$, but was inhibited by the addition of $Co^{+2}$, $Hg^{+2}$, $Zn^{+2}$ and $Ag^{+2}$. NaCl stability of the growth inhibition factor was observed with 50% residual activity at 3% NaCl concentration. Toxicity test showed that the purified B. amyloliquefaciens H41 growth inhibition factor did not affect the live of Japanese flounder (Paralichthys olivaceus) and the effectiveness was 78% of residual lethality compared to commercial antibacterial agents.