• Environmental Engineering Research
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• 제19권1호
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• pp.1-8
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• 2014

Natural organic matter (NOM) is a primary component of fouling in low-pressure membrane filtration, either solely, or in concert with colloidal particles. Various preventive measures to interfere with NOM fouling have been developed and extensively tested, such as coagulation, oxidation, ion exchange, carbon adsorption, and mineral oxide adsorption. Therefore, this article aims to conduct a literature review covering the topics of low-pressure membrane processes, NOM characteristics and fouling behaviors, and diverse fouling control strategies. In-depth explanations and discussion are made regarding why some treatment options are able to remove NOM from source water, but do not reduce fouling. This review provides insight for hybridized membrane processes with respect to NOM removal and fouling mitigation in water treatment.

• 한국환경보건학회지
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• 제16권2호
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• pp.75-82
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• 1990

Carbaryl was degradaded to monomethylamine(MA) by bacterium. which isolated from lake sediment. Its carbaryl degradation was maximized when grown on mineral salt medium conditioning 20 $\mu$M of carbaryl as a sole carbon source at 26${\circ}$C and initial pH 7.0-9.0 Its degradation ability was minimized at initial pH 3.0 and 5.0 The percent conversions { (moles of MA in excess of control / mole of carbaryl added) $\times$ 100} for 10. 20. 40 and 80 $\mu$M of carbaryl were 18.6. 16.1. 18.1 and 11.6 respectively. It suggests that increasing amount of carbaryl added above 80 $\mu$M. the percent conversion should be decreased. The MA production by the bacterium was lineary related to the cultural time. After 7days culture. its percent conversion was 46.2. and this result suggests that a half amount of carbaryl would be hydrolyzed to MA by the bacterium within 8 days.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.350-351
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• 2000

We isolated cellulose-producing bacteria from persimmon vinegar(Korea traditional fermentation food). Some of these strains were selected for cellulose production in agitation culture. On the other hand, it was also found that strains suitable for static culture production were not necessarily suitable for agitation culture. Therefore we estimated the cellulose production of these isolates in static culture. To determine nutritional requirement for the production of bacterial cellulose, several nutrients as carbon source, nitrogen and mineral salt were tested.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2000년도 가을 학술발표회논문집(I)
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• pp.363-368
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• 2000

This paper is an introduction of pessimum program for the identification of alkali-silica reaction of alkali-aggregate reaction which is known as one of a major factor of concrete deterioration. A series of gel-pat testing program was undertaken to observe the reactivity of potentially alkali-silica reactive concrete aggregates which were found to be reactive by previous petrographic examination (ASTM C 295). And then a pessimum program was performed in accordance with mortar-bar test method (ASTM C 227) with different percentage of those reactive components included in the fine aggregate source to determine the pessimum quantity. Chert and quartzite were found to be major components of reactive mineral/rock, and the pessimum condition for chert was about 3%, even though the test was performed with up to 25% of the component. In the case of quartzite, however, the mortar-bar expansion appeared to be directly proportional to the amount of quartzite sample with increasing tested quantity up to 35%. Both of the expansion results were well 3 and 6 month specified maximum limitation of 0.05% and of 0.1% respectively.

• 암석학회지
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• 제2권1호
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• pp.19-31
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• 1993

Oxygen isotope compositions of whole rock and/or mineral separates (quartz and feldspar) have been determined for the granitic and related rocks from the Wolf River Batholith, Wisconsin. Hydrothermal alteration resulting in the decrease of ${\Delta}_{Q-F}$/ values was obaserved locally throughout the batholith. Feldspars of different colors (pink, gray and red) were separated whenever feasible and analyzed. Most red feldspars (An$_{10-30}$/) show the highest and constant ${\delta}^18O$/ values (9.3~10.0 permil) suggesting nearly complete isotope exchange with hydrothermal fluid. Based on ${\delta}^18O$/ values and the alteration temperatures (260~$350^{\circ}C$) estimated from fluid inclusion study, ${\delta}^18O$/ of fluid is calculated to be $5.0{\pm}1.4$ permil. Phanerozoic sedimentary formation water in Wisconsin is most likely the source of the fluid.

• Journal of Microbiology and Biotechnology
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• 제9권5호
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• pp.554-561
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• 1999

A novel estimation method was investigated for determining the concentrations of residual biomass, poly-3-hydroxybutyrate (PHB), and main nutrients including carbon and nitrogen sources, phosphate, and mineral ions from the supplied amount of ammonia solution used for a pH-control solution and nitrogen source in a PHB fermentation. The estimation equations for a batch culture and a fed-batch culture were derived from the relationship between the growth rate of residual biomass and the feed rate of the pH-control solution, and then were applied to the batch culture and the fed-batch cultures of Alcaligenes latus. This method was successfully applied to estimate the concentrations of residual biomass, PHB, and nutrients.

• KSBB Journal
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• 제14권3호
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• pp.365-370
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• 1999

To optimize the culture conditions for Beauveria bassiana 726, the effects of culture medium, pH, and temperature on mycelium and spore production were investigated. The optimum temperature and pH for the cultivation of B. bassiana 726 were 28 $^{\circ}C$ and 5.0, respectively. The optimized medium was composed of 1.0~2.0% total sugar from molasses, 0.5% corn steep liquor and 0.05% KH$_2$PO$_4$. In the cultivation of B. bassiana 726 with the optimum medium, the specific growth rate and substrate utilization were well-fitted with the proposed kinetic model in the shake flask and stirred tank reactor. When the fed-batch cultivation using carbon suorce, nitrogen source, and mineral salt as a feeding medium was compared with batch cultivation in stirred tank reactor, mycelium (12.7 g/L) and spore production (5.4$\times$$10^8/mL$) were enhanced up to 110% and 85%, respectively.

• 대한수의학회지
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• 제29권1호
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• pp.7-11
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• 1989

This study was designed in order to clarify the effect of ethanol drinking on the mineral contents on liver, kidney, muscle and hair. Forty-five rats were divided into 2 groups and a control group. The control group received tap water and the other 2 groups were given 8% and 40% ethanol as drinking source. Liver, kindney, muscle and hair samples were taken and analyzed for zinc, calcium and copper contents by atomic absorption spectrophotometric methods. The results obtained are summrized as follows; 1. The zinc content of muscle showed significant (p<0.01) decrease in both groups. 2. The calcium content of hair showed significant (p<0.1) increase in 8% ethanol group. 3. The copper contents of kidney and muscle in 8% ethanol group and liver in 40% ethanol group showed significant (p<0.1) decrease.

• 한국세라믹학회지
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• 제15권4호
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• pp.199-204
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• 1978

In the present investigation, refined alumina obtained from alunite locally available was used as a aluminous source to synthesize monocalcium aluminate $(CA)_3$ the major mineral constituent of alumina cement. The influence of $SiO_2$ and $Fe_2O_3$ contents on the formation of monocalcium aluminate was studied by X-ray diffraction analysis mainly. About 0.8-1.0 of $Al_2O_3/C_3O$ mol ratio and less than 4 percent of $SiO_2$ were desirable for the effective formation of CA. The small amount of alkali and sulphur contents contained in refined alumina from alunite as the impurities were affected to form $C_4A_3S$ and $C_3S_2$, disadvantageous compounds for the alumina cement, therefore the impurities should be restricted in minimum content as possible.

• 전기학회논문지P
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• 제63권4호
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• pp.327-332
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• 2014

In this paper, the temperature distribution according to the property change of the insulating oil of the power transformer and max temperature were predicted through the ductility interpretation which heat-flow is coupled. By using CFD (Computation Fluid Dynamics) for the interpretation, the temperature distribution of 154kV the class single phase power transformer was predicted. The power loss causing the temperature rise of the transformer was changed to the heat source and we used as the input value for the heat-flow analysis. The temperature distribution was predicted according to the change of the density, specific heat, thermal conductivity and viscosity, that is the ingredient having an effect on the temperature rise of the transformer oil. The mineral oil of 4 kinds used in domestic and international based on the interpreted result was selected and the temperature distribution according to each load and Hot Spot temperature was predicted.