• Journal of the Mineralogical Society of Korea
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• v.20 no.2 s.52
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• pp.71-81
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• 2007

The marble-type dolomite from the Jasung Mine, which was farmed by duplicated affects of contact metamorphism and subsequent hydrothermal alteration, corresponds to a high-purity dolomite ranging up to above 98wt.% in dolomite contents. The dolomite contain minor impurities such as quartz, muscovite, and pyrite. It is characteristic that the dolomite is fairy Fe-rich corresponding to 0.4 wt.% due to the presence of pyrite of possible hydrothermal origin. The dolomite is nearly white-colored and constituting with subhedral crystals ranging $0.35{\sim}0.46mm$M in size, forming equigranular texture. Compared to the typical high-Ca limestone from the Pungchon Formation, the powder characteristics of dolomite is rather superior in milling efficiency, yields of fine particles, and size distribution. In addition, except for iron contents, the dolomite powder is no less superior than the limestone in quality and characteristics as fillers with respects to not only whiteness, oil absorption, and specific surface area but also shape characters such as elongation ratio, aspect ratio, and sphericity. This good characteristics of dolomite powder seem to be originated basically from comparatively higher grade and crystallinity of dolomite. Higher iron contents and the presence of sulfides prevents the dolomite from application for uses by thermal treatment, except for metallic manufacture. However, if proper ore separation procedure is available, the dolomite can be sufficiently utilized as substitutes for high-Ca limestone in most fields of filler industries.

• Korean Journal of Food Science and Technology
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• v.16 no.3
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• pp.261-266
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• 1984

Soymilk residue was washed separately with acetone, ethanol, isopropyl alcohol and n-hexane, and then dried at $45^{\circ}C$. The dried residues were evaluated for drying rate, color and chemical and functional properties. Washing with acetone resulted in the shortest drying time (1hr) and the highest in protein content (48.8%) and in Hunter 'L' value. The dried residues after treatment with acetone and alcohols showed relatively high values of 4.3-4.7g/g and 8.5-8.7g/g in oil and water absorption, respectively. Addition of the acetone treated residue to wheat flour at a level of 10% affected little in Amylograph viscosity while those treated with other solvents caused a significant decrease in the viscosity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.7 no.1
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• pp.43-52
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• 1978

It is well known that water holding capacity plays an important role in processing such meat products as frankfurter-type sausage and fish meat paste products as kamaboko and fish sausage. Consumer qualities of meat products, such as appearance, flavor, as well as drip and shrinkage on cooking, depend greatly on the degree of water binding. In this paper, the water holding capacities of fish paste and salt added paste of white corvenia, Argyrosomus argentatus and file fish, Novodon modestus were measured by centrifuging and press method before and after cooking. And the effects of the addition of phosphates and starch to enhance water binding and stabilize gel formation were also discussed. In addition, the experimental conditions which are suitable to determine the water binding of fish meat paste product were suggested. The results were expressed in percent of water absorbed by the filter paper when pressed or released by pressor or centrifuge to the weight of sample. From the results. a proper condition to measure the water holding capacity of fish meat paste was that 3.0 g of sample which was previously added with 10 percent water was centrifuged at 13,400 G or 12,000 rpm for 15 minutes for the centriguging method and for press method, 0.3 g sample with 10 percent of water added was extracted by an oil pressor at $30\;kg/cm^2$ for 1 minute. Water holding capacity of fresh paste of white corvenia was relatively higher than that of file fish and the difference between species of fish was greater than the difference between measurments by two methods. Sodium chloride had a great effect on enhancing the water holding capacity of fish meat paste giving better effect when 3.0 percent of salt was added. Phosphates used except calcium phosphate revealed a certain enhancement in water binding, yielding best effect at 0.3 percent addition, and metaphosphate seemed to be more effective in order. The addition of corn starch, however, appeared to be not so effective for enhancement of water binding in fresh-salt-added fish meat paste but in cooked fish paste which might be attributed to absorption of water by starch grain and swelling during the heating and consequently enforced gel strength of cooked fish paste. And the water holding capacity of cooked fish paste was proportionally related to its gel strength.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.9
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• pp.1407-1413
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• 2019

Objective: This experiment aimed to investigate the effect of different sources and inclusion levels of dietary fat on productive performance and egg quality in laying hens raised under hot environmental conditions. Methods: A total of 480 Hy-Line Brown laying hens at 31 wk of age were randomly allotted to 1 of 5 experimental diets. The control diet contained 2,800 kcal/kg nitrogen-corrected apparent metabolizable energy with no fat addition. Four additional diets were prepared by adding 2.0% or 4.0% of animal fat (AF) or soybean oil (SO). Energy and nutrient concentrations were consistent among all diets. Diets were fed to hens for 4 weeks. Average daily room temperature and humidity were $26.7^{\circ}C{\pm}1.52^{\circ}C$ and $77.4%{\pm}4.50%$. The heat stress index was approximately 76, indicating that hens were raised under heat stress conditions. Results: Final body weight (BW) was greater (p<0.05) for hens fed diets containing 2.0% or 4.0% AF than for those fed the control diet or diets containing 2.0% or 4.0% SO. The BW gain and feed intake were greater (p<0.05) for hens fed diets containing additional AF or SO than those fed the control diet. Eggshell thickness was the greatest (p<0.05) for hens fed the control diet, but the least (p<0.05) for hens fed diets containing 4.0% SO. Egg yolk color was the greatest (p<0.05) for hens fed the control diet, but the least (p<0.05) for hens fed diets containing 4.0% SO. Conclusion: Inclusion of supplemental fat (AF and SO) in diets exhibits preventative effects on BW loss for hens raised under hot environmental conditions when energy and nutrient concentrations in diets were maintained. The effects were greater for AF than for SO. However, inclusion of supplemental fat in diets decreases eggshell thickness and egg yolk yellowness, possibly due to a reduction in Ca absorption and intake of egg yolk colorants.

• Journal of Conservation Science
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• v.36 no.6
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• pp.533-540
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• 2020

Mt. Neoseongsan (NSS) is the only natural Neorok source in Korea. The geological, historical, and cultural values of NSS were recognized in 2013, and NSS has since been designated and maintained as a natural monument (No. 547), which has restricted the research and utilization of NSS Neorok. The limited NSS Neorok supply has hindered the restoration research of traditional pigments. Recently, a large amount of Neorok has been mined from Mt. Gwangeongsan (GJS) and is expected to be the main supply source of Neorok for restoring traditional pigments. Therefore, this study analyzed the characteristics of NSS- and GJS-Neorok-based pigments to evaluate the feasibility of substituting GJS Neorok for NSS Neorok in pigments. The NSS Neorok was mostly comprised of celadonite, whereas the GJS Neorok included minerals containing glassy phases such as celadonite, cristobalite, tridymite, etc. Because both Neorok samples were vitrified under identical conditions, the GJS Neorok grains were larger than the NSS Neorok ones. The GJS Neorok pigment showed that the chromaticity, grain size, oil absorption, and stability varied depending on the mineral types and contents. In particular, GJS-2 and NSS Neorok showed similar mineral compositions, physical properties, and stabilities, suggesting that GJS-2 can be substituted for NSS Neorok, which has been difficult to source and utilize ever since NSS was designated as a natural monument.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.6
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• pp.818-823
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• 2011

Recently, we showed that green tea extract (GTE) markedly lowers the intestinal absorption of $^{14}C$-benzo[a]pyrene ($^{14}C$-BaP) and enhances its secretion into the biliary route, suggesting a protective role for GTE against body burden. These findings indicate that green tea could be used as an effective dietary means against the toxicity of BaP. The present study, therefore, was designed to investigate if green tea intake could affect the tissue distribution and deposition of $^{14}C$-BaP in rats. Male Sprague-Dawley rats had free access to a nutritionally adequate AIN-93G diet and deionized water. At ~340 g of weight, the rats were injected intraperitoneally with 27.4 kBq of [4-$^{14}C$]-BaP and 5.0 mg of BaP dissolved in $300\;{\mu}L$ of olive oil and then assigned randomly to the following two groups: one group (GTE) of rats was fed the AIN-93G diet with GTE via drinking water at approx. 4.7 mg of catechins/d, whereas the other was fed the same diet but without GTE (control). At 4 wk of dietary treatment with GTE, animals were euthanized and heart, liver, brain, spleen, kidney, retroperitoneal fat, testis, and epididymal fat were collected, weighed, and analyzed for tissue $^{14}C$-BaP. Both the control and GTE groups continuously gained weight throughout the study, but there was no significant difference between the groups. No significant differences were observed in the weights of heart, liver, brain, spleen, kidney, retroperitoneal fat, testis, and epididymal fat. However, the radioactivities of $^{14}C$-BaP, expressed in dpm/g, were significantly lower in the heart, liver, brain, spleen, and epididymal fat of rats receiving GTE as compared to their respective controls. These data indicate that green tea intake markedly lowers tissue accumulation of $^{14}C$-BaP. Taken together, these findings suggest that the decreased tissue levels of BaP by GTE intake may be associated with lowered intestinal absorption of BaP and its enhanced secretion into the bile.

• The Journal of Engineering Geology
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• v.15 no.2 s.42
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• pp.169-184
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• 2005

Unagsan and Sogrisan granites are widely distributed in the northern Gyeonggi massif and middle Ogcheon belt, respectively, and they show different petrologic characteristics as follows. The former has compact textures and light grey colors, and the latter has spotted miarolitic textures and pink colors. Most of the samples selected for tests are fresh and coarse-grained. And bored core samples were prepared so that they are vertical to the rift plane. The results of modal analysis show that Unagsan granite has significantly higher quartz and plagioclase contents (Qz+Pl) than Sogrisan granite. In contrast, alkali feldspar content (Af) of Sogrisan granite is much higher than that of Unagsan granite. Therefore, it is believed that the light grey colors of Unagsan granite are due to relatively high Qz+Pl, and the pink colors of Sogrisan granite are caused by higher Af. Fractures in Sogrisan granite have strongly perpendicular strike patterns and more dip values close to vertical compared with the fractures in Unagsan granite. Results of the fracture pattern analysis suggest that the Sogrisan granite has better potential to produce dimension stones than the Unagsan granite. However, miarolitic textures often found in the Sogrisan granite may be one of the factors reducing the granite quality. The Unagsan and Sogrisan granites have similar specific gravity values of 2.60 and 2.57, respectively. Absorption ratios and porosity values of Sogrisan granite are higher than those of Unagsan granite, and they shows linearly positive correlations. Compressive and tensile strengths of the Unagsan granite are generally higher than those of Sogrisan granite. These differences and variation trends found in physical properties of Unagsan and Sogrisan granite can be explained by the differences in the textures of Unagsan and Sogrisan granites, namely compact and miarolitic textures respectively. For Unagsan granite, compressive and tensile strengths are negatively correlated with porosity but for Sogrisan granite no specific correlations are found. This is probably due to the irregular dispersion patterns of miarolitic textures formed during the later stages of magmatic processes. Contrary to the trends found in absorption ratios, both granites have similar values of abrasive hardness, which can be explained by higher Qz+Af of the Sogrisan granite than those of the Unagsan granite and that quartz and alkali feldspar have relatively larger hardness values. For Sogrisan granite, compressive strength shows slightly positive correlations with Qz+Af+Pl and negative correlations with biotite and accessory mineral contents (Bt+Ac).

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.12 no.12
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• pp.1098-1125
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• 2000

A review on the papers published in the Korean Journal of Air-Conditioning and Refrigerating Engineering in 1998 and 1999 has been done. Focus has been put on current status of research in the aspect of heating, cooling, ventilation, sanitation and building environment. The conclusions are as follows. 1) A review of the recent studies on fluid flow, turbomachinery and pipe-network shows that many experimental investigations are conducted in applications of impingement jets. Researches on turbulent flows, pipe flows, pipe-networks are focused on analyses of practical systems and prediction of system performance. The results of noise reduction in the turbomachinery are also reported. 2) A review of the recent studies on heat transfer analysis and heat exchanger shows that there were many papers on the channel flow with the application to the design of heat exchanger in the heat transfer analysis. Various experimental and numerical papers on heat exchanger were also published, however, there were few papers available for the analysis of whole system including heat exchanger. 3) A review of the recent studies on heat pump system have focused on the multi-type system and the heat pump cycle to utilize treated sewage as the heat source. The defrosting and the frosting behaviors in the fin-tube heat exchanger is experimentally examined by several authors. Several papers on the ice storage cooling system are presented to show the dynamic simulation program and optimal operation conditions. The study on the micro heat pipes for the cooling of high power electronic components is carried out to examine the characteristics of heat and mass transfer processed. In addition to these, new type of separate thermosyphon is studied experimentally. 4) The recent studies on refrigeration/air conditioning system have focused on the system performance and efficiency for new alternative refrigerants. New systems operating with natural refrigerants are drawing lots of attention. In addition to these, evaporation and condensation heat transfer characteristics of traditional and new refrigerants are investigated for plain tubes and also for microfin tubes. Capillary tubes and orifice are main topics of research as expansion devices and studies on thermophysical properties of new refrigerants and refrigerant/oil mixtures are widely carried out. 5) A review of the recent studies on absorption cooling system shows that numerous experimental and analytical studies on the improvement of absorber performance have been presented. Dynamic analysis of compressor have been performed to understand its vibration characteristics. However research works on tow-phase flow and heat transfer, which could be encountered in the refrigeration system and various phase-change heat exchanger, were seemed to be insufficient. 6) A review of recent studies on duct system shows that the methods for circuit analysis, and flow balancing have been presented. Researches on ventilation are focused on the measurement of ventilation efficiency, and variation of ventilation efficiency with ventilation methods by numerous experimental and numerical studies. Furthermore, many studies have been conducted in real building in order to estimate indoor thermal environments. Many research works to get some information for cooling tower design have been performed but are insufficient. 7) A review on the recent studies on architectural thermal environment and building mechanical systems design shows that thermal comfort analysis is sitting environment, thermal performance analysis of Korean traditional building structures., and evaluation of building environmental load have been performed. However research works to improve the performance of mechanical system design and construction technology were seemed to be insufficient.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.7
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• pp.491-498
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• 2009

We studied to develop high-efficiency removal system of odor and VOCs(Volatile Organic Compounds) from environmental infrastructure facilities and oil refineries, painting facilities and so on. It can replace RTO and RCO. We tried an removal experiment for VOCs (toluene, xylene, benzene, MEK(methyl ethyl ketone), ethanol, formalin etc. and odor compounds (hydrogen sulfide, etc.). In process, as pre-treatment we used the scrubber with vortex flow (Multi-scrone) to remove the hydrophilic VOCs and as post-treatment, used fibrous bio-filter to remove the hydrophobic VOCs. This hybrid system remove with high efficiency both the hydrophilic VOCs and hydrophobic VOCs. And we tried to make this system to be compact. In experiment using Multi-scrone, contact time is 2~3 seconds and absorption scrubbing water is diaphragm-type electrolysis water. hydrophilic VOCs like ethanol and relatively hydrophilic odor compounds like hydrogen sulfide is excellent, these substances has been removed almost completely, respectively 95~99%, 93~97%. And for MEK, formalin also Showed a high removal efficiency, respectively 78~90%, 72~85%. But in experiment using Multi-scrone, the hydrophobic VOCs like BTX showed a low removal efficiency, respectively 16~22%, 12~18%, 8~16%. In hydrophobic VOCs, toluene removal experiment using fibrous bio-filter, early efficiency was low but after 10days, adaptation period showed high efficiency 85~95%. but in the mixed phase, toluene and MEK efficiency reduced 5~10%. this show microorganism treat first MEK easy to remove. The removal efficiency for MEK using the fibrous biofilter was stable, 80~92%. This hybrid system is also high economical efficiency for RTO. This system reduce more than 50% the cost of equipment and maintenance. As a result, we expect this technology is in the limelight as high efficiency treatment of VOCs in mid-low price.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.23 no.6
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• pp.449-469
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• 2011

This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigerating Engineering during 2010. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) Research trends of thermal and fluid engineering have been surveyed as groups of general thermal and fluid flow, fluid machinery, and new and renewable energy. Various topics were presented in the field of general thermal and fluid flow. Research issues mainly focused on the thermal reliability of axial fan and compressor in the field of fluid machinery. Studies on the design of ground source heat pump systems and solar chemical reactors were executed in the field of new and renewable energy. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics and industrial heat exchangers. Researches on heat transfer characteristics included heat transfer in thermoelectric cooling/power generation systems, combined heat and power systems, carbon nano fluid with PVP, channel filled with metal foam and smoke ventilation in a rescue station of a railroad tunnel. Also the studies on flow boiling of R123/oil mixture in a plain tube bundle and R410A charge amount in an air cooled mini-channel condenser were reported. In the area of industrial heat exchangers, researches on plate heat exchanger, shell and tube heat exchanger, enthalpy exchanger, micro channel PCHE were performed. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics and industrial heat exchangers. Researches on heat transfer characteristics included heat transfer in thermoelectric cooling/power generation systems, combined heat and power systems, carbon nano fluid with PVP, channel filled with metal foam and smoke ventilation in a rescue station of a railroad tunnel. Also the studies on flow boiling of R123/oil mixture in a plain tube bundle and R410A charge amount in an air cooled mini-channel condenser were reported. In the area of industrial heat exchangers, researches on plate heat exchanger, shell and tube heat exchanger, enthalpy exchanger, micro channel PCHE were performed. (3) Refrigeration systems with alternative refrigerants such as hydrocarbons, mixed refrigerants, and CO2 were studied. Performance improvement of refrigeration systems are tried applying various ideas of refrigerant subcooling, dual evaporator with hot gas bypass control and feedforward control. The hybrid solar systems combining the solar collection devices with absorption chillers or compression heat pumps are simulated and studied experimentally as well to improve the understanding and the feasibility for actual applications. (4) Research trend in the field of mechanical building facilities has been found to be mainly focused on field applications rather than performance improvements. Various studies on heating and cooling systems, HVAC facilities, indoor air environments and energy resources were carried to improve the maintenance and management of building service equipments. In the field of heating and cooling systems, papers on a transformer cooling system, a combined heat and power, a slab thermal storage and a heat pump were reported. In the field of HVAC facilities, papers on a cooling load, an ondol and a drying were presented. Also, studies on HVAC systems using unutilized indoor air environments and energy resources such as air curtains, bioviolence, cleanrooms, ventilation, district heating, landfill gas were studied. (5) In the field of architectural environment and energy, studies of various purposes were conducted such as indoor environment, building energy, renewable energy and green building. In particular, renewable energy and building energy-related researches have mainly been studied reflecting the global interest. In addition, many researches which related the domestic green building certification of school building were performed to improve the indoor environment of school.