• Journal of Korean Society on Water Environment
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• v.24 no.1
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• pp.123-128
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• 2008

The Dissolved Organic Carbon (DOC) existing in a water includes both hydrophobic and hydrophilic substances however, most of the discussion focuses on hydrophobic substances. The hydrophobic fraction was easily removed by absorption or coagulation more than hydrophilic fraction. Therefore, control of the hydrophilic fraction is very important in water treatment process. This study is to determine the variation of DOC, the removal efficiency of DOC, and Trihalomethane formation potential (THMFP) after each stage of water treatment process by fractionating Natural Organic Matters (NOM) into hydrophobic and hydrophilic substance. DOC from raw water was fractionated at acidic pH (pH<2) using XAD 8 resin column, into two fraction : hydrophobic substance (i.e. humic substance) adsorbed on XAD 8 and hydrophilic substance which represent the organics contained in the final effluent. THMFP was carried out according to the following set condition: Cl2/DOC=4 mg/mg, incubation at $25^{\circ}C$ in darkness, pH 7 adjust with HCl or NaOH as necessary, and 72hour-contact time. THMs analyzed in this study were chloroform, bromodichloromethane, dibromochloromethan, and bromoform. Sewage was almost evenly split between the hydrophobic (56%) and hydrophilic fraction (44%). But, Aldrich humic substance (AHS) was found to contain less hydrophilics (14%) than hydrophobics (86%). The formation of THMs may depend on the source which is characterized by the composition of organic matters such as AHS and sewage. The THMFP yield of sewage and AHS were assessed as follows. The value of the THMFP reaction yield, AHS $172.65{\mu}g/mg$, is much higher than that of sewage $41.68{\mu}g/mg$. This illustrates possible significant difference in THMFP according to the component type and the proportion of organic matter existing in water source. Apparently AHS react with chlorine to produce more THMFP than do the smaller molecules found in sewage. Water treatment process may reduce THMFP, nevertheless residual DOC (the more hydrophilic substance) has significant THMFP. Further reduction in organic halide precursors requires application of alternative treatment techniques.

• Journal of the Mineralogical Society of Korea
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• v.26 no.2
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• pp.87-99
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• 2013

The occurrence, mineralogical characteristics, and origin of the dolomite ores were investigated from major dolomite mines in South Korea. Mineralogical and textural properties of the ores and associated minerals were analyzed using X-ray diffraction, thin section petrography, and scanning electron microscopy. Dolomite ores were light to dark gray in color and mainly composed of dolomite in varying particle size with minor amounts of calcite, quartz and micas. Calcite, quartz, illite, feldspar, kaolin minerals, and chlorite occurred in local veins, dikes and alteration zones. Sepiolite and wollastonite occurred in the altered part of some mine. Asbestos minerals such as chrysotile and tremolite, however, were not identified in the present study. Reddish brown to yellow clay materials were mainly composed of illite, occasionally associated with kaolin minerals and smectite. These clay minerals might be a product of the local hydrothermal alteration related to the dyke intrusion and subsequent weathering. As well indicated in the previous studies, mineral composition, texture, and occurrence of the dolostone beds suggest their formation through the diagenesis of carbonate sediments deposited in the shallow sea during the Precambrian to Paleozoic period.

• Journal of the Korea Organic Resources Recycling Association
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• v.11 no.1
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• pp.91-91
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• 2003

시험은 대조구 0%와 남은 음식물에 Protein의 요구량 수준을 각각 높인 10%, 20%, 30%, 40%, 대조구에 녹차 부산물(GTB) 첨가구 1.0%, 남은 음식물 30% + 녹차 부산물 (GTB) 1.0%로 총 7처리 4반복으로 하였으며, 반복당 6수씩 개체별로 사양 실험을 실시하고, 산란율, 난중, 난각두께, 난황색, Thiobarbituric acid (TBA) 및 관능검사 등을 측정한 결과는 다음과 같다. 1. 산란율은 남은 음식물 10%, 20% 및 40% 첨가구에서 각각 82.65%, 81.54% 및 82.27%로 높게 나타났으나 남은 음식물 30%첨가구는 75.34%로 낮게 나타났으며 통계적 유의차를 보였다 (P<0.05). 대조구가 72.87%가 가장 낮게 나타났으며 (P<0.05), 주령별로는 주령이 증가할수록 산란율이 다소 감소하는 경향을 보였다. 2. 난중은 전 처리구중 가장 높은 경향을 보인 것은 남은 음식물 30% + GTB 1%처리구가 63.78로 높은 경향을 보였다. 가장 낮은 난중은 남은 음식물 10%처리구가 60.02로 나타났다 (P<0.05). 3. 산란량은 전 처리구에서 남은 음식물 30% + GTB 1%가 52.53g으로 높게 나타났고, 가장 낮은 산란량을 보인 것은 대조구가 45.32g으로 가장 낮게 나타났으며 통계적 유의차를 보였다 (P<0.05). 4. 사료 요구율은 남은 음식물 20%첨가구가 2.86으로 높게 나타났으며, 낮은 요구율은 남은 음식물 10%첨가구가 2.47으로 낮게 나타났으며 통계적 유의차를 보였다 (P<0.05). 전 처리구간에서 사료 요구율은 주령이 증가할수록 요구율이 증가하는 경향을 보였다. 5. 콜레스테롤은 대조구 + GTB 1.0%첨가구가 13.923으로 높게 나타났다. 가장 낮은 콜레스테롤은 남은 음식물 40%처리구가 12.003으로 낮게 나타났다. 남은 음식물을 첨가한 처리구가 난황 내 콜레스테롤 함량이 낮아지는 경향을 보였으나 남은 음식물 30%첨가구가 12.835로 높은 수치를 보였으며 통계적 유의차는 나타나지 않았다 (P>0.05). 6. TBA가 가장 높은 처리구간은 1주에는 남은 음식물 40%첨가구가 3.205로 높게 나타났으며 2주에는 남은 음식물30%첨가구가 3.275로 높게 나타났다. 마지막 주에는 3.947로 높게 나타났다. 이 결과로 볼 때 남은 음식물을 첨가한 처리구가 대체적으로 산패도가 높게 나타나는 경향을 보였으며 통계적 유의차는 나타나지 않았다 (P>0.05).

• Journal of Microbiology and Biotechnology
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• v.24 no.7
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• pp.943-953
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• 2014

The XylH gene (1,167-bp) encoding a novel hemicellulase (41,584 Da) was identified from the genome of Microbacterium trichothecenolyticum HY-17, a gastrointestinal bacterium of Gryllotalpa orientalis. The enzyme consisted of a single catalytic domain, which is 74% identical to that of an endo-${\beta}$-1,4-xylanase (GH10) from Isoptericola variabilis 225. Unlike other endo-${\beta}$-1,4-xylanases from invertebrate-symbiotic bacteria, rXylH was an alkali-tolerant multifunctional enzyme possessing endo-${\beta}$-1,4-xylanase activity together with ${\beta}$-1,3/${\beta}$-1,4-glucanase activity, which exhibited its highest xylanolytic activity at pH 9.0 and 60oC, and was relatively stable within a broad pH range of 5.0-10.0. The susceptibilities of different xylosebased polysaccharides to the XylH were assessed to be as follows: oat spelts xylan > beechwood xylan > birchwood xylan > wheat arabinoxylan. rXylH was also able to readily cleave p-nitrophenyl (pNP) cellobioside and pNP-xylopyranoside, but did not hydrolyze other pNP-sugar derivatives, xylobiose, or hexose-based materials. Enzymatic hydrolysis of birchwood xylan resulted in the product composition of xylobiose (71.2%) and xylotriose (28.8%) as end products.

• Korean Journal of Food Science and Technology
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• v.30 no.3
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• pp.552-556
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• 1998

In this study, the quality stability of a kind of natural seasoning material, the mixture of enzyme treated mackerel meat and Laminaria powder during the storage was investigated by measuring the TBA(thiobarbituric acid)value, extend of browning, changes in amino nitrogen and chlorophyll a, and fatty acid composition, and the results of sensory evaluation. Addition of sodium alginates (0.08%) and calcium carbonate (0.02%) seemed effective as a binder to yield clarity of the hot water extract of the product. In results, the mixture of Laminaria powder and the enzyme treated mackerel meat added with 0.08% sodium alginate and 0.02% calcium carbonate was more stable in overall quality than the other cases of preparation. And the taste of the mixture could favorably compete with that of dried anchovy extracts.

• Journal of Environmental Science International
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• v.16 no.10
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• pp.1203-1208
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• 2007

Feathers are produced in huge quantities as a waste product at commercial poultry processing plants. Since feathers are almost pure keratin protein, feather wastes represent an alternative to more expensive dietary ingredients for animal feedstuffs. Generally they become feather meal used as animal feed after undergoing physical and chemical treatments. These processes require significant energy and also cause environmental pollutions. Therefore, biodegradation of feather by microorganisms represents an alternative method to prevent environment contamination. The aim of this study was to investigate cultural conditions affecting keratinolytic protease production by Bacillus pumilus RS7. We also assessed the nutritive value of microbial and alkaline feather hydrolysates, The composition of optimal medium for the keratinolytic protease was fructose 0.05%, yeast extract 0.3%, NaCl 0.05%, K2HPO4 0.03%, KH2PO4 0.04% and MgCl2 6H2O 0.01%, respectively. The optimal temperature and initial pH was $30^{\circ}C$ and 9.0, respectively. The keratinolytic protease production under optimal condition reached a maximum after 18 h of cultivation. Total amino acid content of feather hydrolysates treated by NaOH and B. pumilius RS7 was $113.8\;{\mu}g/ml$ and $504.9\;{\mu}g/ml$, respectively. Essential amino acid content of feather hydrolysates treated by NaOH and B. pumilius RS7 was $47.2\;{\mu}g/ml$ and $334.0\;{\mu}g/ml$, respectively. Thus, feather hydrolysates have the potential for utilization as an ingredient in animal feed.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.9 no.5
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• pp.510-515
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• 1999

Synthesize of anatase type $TiO_2$ from $TiCl_4$ solution was studied. KOH was used on dehydration reaction of $TiCl_4$ solution. Products of dehydration reaction was calcined at 300, 500, 700, 900, $1000^{\circ}C$ during 1hour. Calcined products was studied by XRD, DTA, and FT-IR for effect of calcined temperature. The results are as follow. \circled1 Product pf dehydration reaction at$ 90^{\circ}C$ was semicrystalline anatase type $TiO_2$ because it has a peak vary broad and low at the position of anatase crysral XRD pattern. \circled2 Pure titanium oxide semi-crystalline products were produced at acid pH condition which convert to anatase crystal at $300^{\circ}C$ and to rutile crystal at $700^{\circ}C$. \circled3 The chemical composition of semicrystalline products which was produce at alkali pH conditions, were potasium titante. Potasium-titanate semi-crystalline products crystallized at 630~$640^{\circ}C$ \circled4 The transition temperature of potassium dopped titanium oxide semi-crystalline products was increased with the contents of potasium. \circled5 The optimum synthesise condition of anatase $TiO_2$ products from $TiCl_4$ and KOH are pH 3~5 and $300^{\circ}C$ calcination.

• Korean Journal of Plant Resources
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• v.18 no.2
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• pp.270-278
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• 2005

This experiment was conducted to develop and design a product that is convenient and helpful to both patients and ordinary people who want to maintain their health. In this experimentation, the experimental rat have been given with high fat food to induce Diabetes. Organic brown rice was given as their main energy source and natural complex food, most of materials were freeze-dried, was given to observe its effects on their glucose amount in the plasma. The results are as follows. During 28 days of basal diets, as observing their weight variations, normal group gained weights, but the natural complex food(NCF) groups lost their weights. As comparing the amount of neutral fat levels in the plasma between the diabetes group who just had basal group and one who had NCF, group with NCF groups' level was much lower than the other group who just had basal food. As comparing total cholesterol levels in the plasma, with diabetes group with basal food, $50\%$ and $100\%$ NCF groups' levels were lowered than that group. Regarding HDL-cholesterol level, all NCE groups had around 30mg/dl and there were not much fluctuation among groups. As for LDL-cholesterol level, the $100\%$ NCF group had the lowest level and showed almost the same as the normal group. The amounts of the glucose in the plasma were lowered in all NCF groups. Among those NCE groups, $100\%$ NCF group had 120mg/dl to reach almost the same as the normal group.

• Nuclear Engineering and Technology
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• v.48 no.1
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• pp.274-284
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• 2016

Purpose: The purpose of this work is to describe the spectrometric analysis of gaseous cloud formation over reactor mixed uranium-and-plutonium (UP) fuel $(U_{0.8}Pu_{0.2})O_2$ samples heated to a temperature $>2,000^{\circ}C$, and thus forecast and evaluate radiation hazards threatening humans who cope with the consequences of any accident at a fission reactor loaded by UP mixed oxide $(U_{0.8}Pu_{0.2})O_2$, such as a mixture of 80% U and 20% Pu in weight. Materials and methods: The UP nuclear fuel samples were heated up to a temperature of over $2,000^{\circ}C$ in a suitable assembly (apparatus) at out-of-pile experiments' implementation, the experimental in-depth study of metabolism of active materials in living organisms by means of artificial irradiation of pigs by plutonium. Spectrometric measurements were carried out on the different exposed organs and tissues of pigs for the further estimation of human internal exposure by nuclear materials released from the core of a fission reactor fueled with UP mixed oxide. Results: The main results of the research described are the following: (1) following the research on the influence of mixed fuel fission products (radioactive isotopes being formed during reactor operation as a result of nuclear decay of elements included into the fuel composition) on living organisms, the authors determined the quantities of plutonium dioxide ($PuO_2$) that penetrated into blood and lay in the pulmonary region, liver, skeleton and other tissues; and (2) experiments confirmed that the output speed of plutonium out of the basic precipitation locations is very small. On the strength of the experimental evidence, the authors suggest that the biological output of plutonium can be disregarded in the process of evaluation of the internal irradiation doses.

• Journal of the Korean Ceramic Society
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• v.20 no.2
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• pp.135-146
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• 1983

This study is to investigate the properties of domestic fly ash for utilization as data in regard to fly ash which is by-product of domestic coal powder plants and the possibility of utilization as insulation material of domestic fly ash. Composition refractoriness size distribution density contents of hollow particles and crystalline phase were examined as the properties of domestic fly ash. As to the fired test pieces of fly ash by itself that varied contents of hollow particles with four kinds and of the fly ash-clay-saw dust system linear shrinkage bulk density app. porosity compressive strength thermal conductivity and structures were investigated for the possibility of utilization as an insulation material. The results are as follows : 1. The properties of the fly ash I) The constituent particle of the fly ash is spherical and it contains not a few hollow particles (floats by water 0.30-0.50 floats by $ZnCl_2$ aq.(SpG=1.71) 6.97-16.72%). ii) The chemical compositions of fly ash are $SiO_243.9-54.1%$ , $Al_2O_321.0-30.7%$ Ig loss is 7.4-24.1% and the principal of Ig loss is unburned carbon. iii) Fly ash was not suitable to use for mortar and concrete mixture because Ig. loss value is higher than 5% 2. Utilization as insulation material I) The test pieces of original fly ash floats by water floats by ZnCl2 aq(SpG=1.71) p, p t by ZnCl2 aq.(SpG=1.71) that were fired at 110$0^{\circ}C$ represented 0.11-0.18 kcal/mh$^{\circ}$ C as thermal conductivity value. ii) The test pieces which (76.5-85.5) wt% fly ash-(8.5, 9.5) wt% clay-(5.0-15.0) wt% saw dust system(68.0-72.0) wt% fly ash -(17.0-18.0)wt% clay-(10.0-15.0) wt% saw dust system and 59.5 wt% fly ash-25.5 wt% clay-15.0wt% saw dust system were fired at 110$0^{\circ}C$ the thermal conductivity was less than 0.1Kcal/mh$^{\circ}$ C. iii) In view of thermal conductivity and economic aspect insulation materials which added saw dust as blowing agent and clay as inorganic binder are better than that of fly ash as it is or separated hollow fly ash particles. iv) When the saw dust contents increased in the (59.5-90.0) wt% saw dust system and when amount of clay de-creased and firing temperature decreased under the condition of equal addition of saw dust app. porosity increased but bulk density compressive strength and thermal conductivity decreased.