• 보존과학연구
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• s.6
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• pp.48-57
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• 1985

This report described the corrosion structure of excavated iron artifacts in terms of simple model based on the knowledge of the corrosion process. (Fig.1)(Table 1,2)In storing the objects, there are basically three ways in which they either break in wedges, flakes and dish-shaped flakes. Completely mineralized objects or those with only a small iron core tend to break into wedges and more solid objects either split small dish-shaped flakes or large flat ones.(Fig. 2,3,4)There are two ways, therefore, to prevent this from happening. One is to keep the artifacts rigorously dried in Silica-gel, never allowing the relative humidity to rise. This is feasible which the artifacts are in store but causes great difficulty if they are wanted for museum display. Because they still contain $ FeCl _2$ they are always at risk ; they contain the seeds of their own destruction. The other alternative is to use of washing process to dissolve out the $ FeCl _2$. In this connection, many different methods to stabilize the artifact have been employed; boiling iron in frequent changes of water, soaking in Na-sesquicarbonate solution, soaking in alkaline Na-sulphite solution. In this report, introduced the alkaline sulphite method by the N.A. North and C.Pearson.Finally, Let me extend my thanks to Ancient Monument Lab., Museum of London Conservation Lab., British Museum Conservation Div. and National Maritime Museum Conservation Lab. who have helped me and made many valuable suggestions.

• Nuclear Engineering and Technology
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• v.41 no.8
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• pp.1015-1024
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• 2009

The presence of a non-condensable gas can considerably reduce the level of condensation heat transfer. The non-condensable gas effect is a primary concern in some passive systems used in advanced design concepts, such as the Passive Residual Heat Removal System (PRHRS) of the System-integrated Modular Advanced ReacTor (SMART) and the Passive Containment Cooling System (PCCS) of the Simplified Boiling Water Reactor (SBWR). This study examined the capability of the Multi-dimensional Analysis of Reactor Safety (MARS) code to predict condensation heat transfer in a vertical tube containing a non-condensable gas. Five experiments were simulated to evaluate the MARS code. The results of the simulations showed that the MARS code overestimated the condensation heat transfer coefficient compared to the experimental data. In particular, in small-diameter cases, the MARS predictions showed significant differences from the measured data, and the condensation heat transfer coefficient behavior along the tube did not match the experimental data. A new method for calculating condensation heat transfer coefficient was incorporated in MARS that considers the interfacial shear stress as well as flow condition determination criterion. The predictions were improved by using the new condensation model.

• Journal of ILASS-Korea
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• v.5 no.4
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• pp.57-65
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• 2000

For this research an extension of the LIF technique that the LIEF(Laser Induced Exciplex Fluorescence) technique has been used LIEF technique is the unique method to allows the visualization of fuel vapor phase and liquid phase individually by capturing each signals of them. In this work performed that the basic procedure for advanced LIEF technique using TEA and benzene as dopants md high power KrF excimer laser to excite the dopants. Iso-octane is used as the fuel because it does not absorb light at the laser wavelength. The boiling point of benzene and TEA are $81^{\circ}C\;and89^{\circ}C$, respectively, in comparison to $99^{\circ}C$ for iso-octane. It is observed that the behavior and distribution of high pressed fuel injection from various test condition. The injection pressure is set as 3MPa. and 5MPa. And the ambient pressure of test chamber is atmospheric pressure and 1MPa, the ambient temperature of chamber is room temperature, $300^{\circ}C\;and\;500^{\circ}C$ to imitate the condition of GDI engine cylinder.

• Corrosion Science and Technology
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• v.11 no.5
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• pp.196-204
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• 2012

Corrosion failure of petrochemical facilities is one of the difficulties in maintenance, since operating conditions of crude oil production, storage, and refinement are very aggressive. UNS N08810, which has been used for crude oil transportation pipes and storage tanks in petrochemical industries, shows good resistance to general corrosion and localized corrosion in several environments. Among its environments, UNS N08810 showed better corrosion resistance in fuel gas containing sulfuric acid and phosphoric acid and sulfur. However, ductility and toughness at high temperature over about $500^{\circ}C$ were greatly reduced due to microstructural change. In general, welding process is the representative method to join the parts in industrial components. Because the alloy by welding can be sensitized and corroded, the manufacturing process should be controlled. In this work, UNS N08810 was used and heat treatment conditions including solution and stabilization treatments were controlled. Oxalic acid etch test by ASTM A262 Practice A was done to evaluate the qualitative sensitization in room temperature. Huey test by ASTM A262 Practice C was done to evaluate the intergranular corrosion rate in boiling 65% $HNO_3$ solution. Also, the microstructure by thermal history was analyzed. Experimental alloy showed high intergranular corrosion rate and its corrosion mechanism was elucidated.

• Journal of Power System Engineering
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• v.18 no.5
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• pp.11-15
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• 2014

Currently, there are active researches being conducted on a new combustion technology that can reduce emission quantity while enhancing vehicle performance as well as Improving fuel quality. In a gasoline engine that uses petroleum, high volatility makes it easy to jump spark ignition and prevent knocking phenomenon that occurs inside an engine. In a diesel engine that uses diesel fuel, high volatility reduces combustion residues and toxic gas and is therefore good for protecting the environment. Therefore, for fuel used in a vehicle, volatility is an important factor that influences not only engine performance but also environmental protection. This research conducted a distillation experiment using gasoline and diesel fuel for vehicles produced by domestic oil companies. The test was conducted in accordance with the method of distillation experiment described in KS M ISO3405. In addition, it used the result of analysis from the experiment to examine visual distillation characteristics of each fuel and developed a formula based on distillation temperature.

• Korean Journal of Microbiology
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• v.11 no.2
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• pp.101-106
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• 1973

The microwave of 2450 MHz, generated by a household cooking oven, was evaluated for its applicability to melt various rehydrated media and to remove dissolved oxygen from tubed media for anaerobic culture. The effect on the sterilization of E. coli in selective media was also evaluated. The following results were obtained. 10 The microwave oven was useful in saving time for melting media and in eliminating heat and combustion gas from the laboratory, which were inevitable by-products in the conventional flame method. 2) Dissolved oxygen could be removed without boiling over by exposing the tubes of anaerobic culture medium after putting them in a wire basket in a beaker with water. 30 The count of E. coli during the melting of MacConkey and EMB agar were similar to those treated with open flame. The microwave treatment was not considered a possible mean to replace autoclaving even in these selective media.

• The Korean Journal of Physiology
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• v.4 no.1
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• pp.55-57
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• 1970

Erythropoietic activity in anemic Plasma of chronic posthemorrhagic anemic men was studied in rats after subcutaneous injection of anemic plasma. Anemic plasma was obtained from blood donors who sold their blood once or twice a week for one or two years to blood bank. Hemoglobin concentrations of 8 blood donors ranged between 4.6 and 8.4 gm/100 ml. Pooled plasma was treated by acidification-boiling method and adjusted to pH 7.5 by adding 0.1 N NaOH. 7ml/kg and 15ml/kg of anemic plasma filtrate was injected to 2 groups of rats respectively for 7 and 8 days. Hemoglobin concentrations, red blood cell counts and reticulocyte counts were observed before and after injection of anemic plasma and no change was induced by the injection. Subsequently, it was concluded that there was no erythropoietin of high titer in the plasma of chronic post-hemorrhagic anemic men.

• Membrane Journal
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• v.18 no.3
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• pp.214-218
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• 2008

Protain affinity membranes based on PES-BSA was preapared by the electrospinning method. The process problem caused by the electrospining was solved by using HFB having high solubility and boiling point. It was expecting that the mass production of protein affinity membrane would be possible with broad range of optimized temperature and humidity. BSA in the PES nanofiber was confirmed by the color change from colorless to violet during the biuret test. The buffer solution with DMSO showed that the amount of elution was 5 times higher than the one when the buffer solution without DMSO was used. This is due to the restriction effect of DMSO on the dissociation of L-tryptophan from BSA during the washing step.

• The Korean Journal of Mycology
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• v.13 no.2
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• pp.65-74
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• 1985

Aspergillus niger IMI 41873 was cultured by the method of synchronous and submerged culture. Its sporulation occurred in the culture. Ribonucleic acids were extracted at each stage of life cycle. These RNAs were digested, separated and determined by P.E.I. cellulose TLC and HPLC methods. The levels of ribonucleic acids in sporulating mycelia were higher than those of conidiophore and phialide forming mycelia. Inosine 5-monophosphate and adenosine 5-monophosphate derivatives were found in HPLC separations. The levels of inosine 5-monophosphate and adenosine 5-monophosphate derivatives per ribonucleic acid were constant through differentiation. After the standard purine necleosides and boiling water extracts from A. bisporus, F. velutipes and L. edodes were added into the culture, their effects on sporulation were examined. Sporulation was greatly enhanced in each adding experiment.

• Journal of the Korean Society for Heat Treatment
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• v.23 no.5
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• pp.249-256
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• 2010

Water jet impingement cooling has been widely used in a various engineering applications; especially in cooling of hot steel plate of steelmaking processes and heat treatment in hot metals as an effective method of removing high heat flux. The effects of cooling water temperature on water jet impingement cooling are primarily investigated for hot steel plate cooling applications in this study. The local heat flux measurements are introduced by a novel experimental technique that has a function of high-temperature heat flux gauge in which test block assemblies are used to measure the heat flux distribution during water jet impingement cooling. The experiments are performed at fixed flow rate and fixed nozzle-to-target spacing. The results show that effects of cooling water temperature on the characteristics of jet impingement heat transfer are presented for five different water temperatures ranged from 5 to $45^{\circ}C$. The local heat flux curves and heat transfer coefficients are also provided with respect to different boiling regimes.