• Preventive Nutrition and Food Science
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• v.12 no.1
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• pp.40-45
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• 2007

The effects of drying methods on the physicochemical properties of chaga (Inonotus obliquus) mushroom powder were investigated. Scanning electron micrograph revealed that freeze drying produced smaller particle- sized samples which in turn resulted in higher porosity than did vacuum and hot-air drying. Samples prepared by freeze drying showed a significantly higher L*-value as compared with those prepared by hot-air drying and vacuum drying (p<0.05). The lightness (L*-value) significantly decreased with increasing relative humidity and storage temperature regardless of drying method (p<0.05). The yellowness (b*-value) increased significantly with increasing relative humidity (p<0.05). Browning index was significantly lower in samples prepared by freeze drying (p<0.05) but not significantly different between samples dried by hot-air and vacuum drying. Freeze dried sample exhibited a significantly higher degree of rehydration than other samples (p<0.05) probably due to the small particle size. Water solubility of the freeze dried sample was higher than those of the other methods while swelling ratio of the same sample appeared to be lower than those of others. Freeze dried chaga mushroom powder contained significantly lower amount of total phenolics and total sugar as compared to other samples (p<0.05).

• Analytical Science and Technology
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• v.8 no.4
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• pp.807-814
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• 1995

Accurate measurements of ozone precursors are required to understand the process and extent of ozone formation in rural and urban areas. Nonmethane hydrocarbons (NMHCs) have been identified as important ozone precursors. Identification and quantification of NMHCs are difficult because of the large number present and the wide molecular weight range encountered in typical air samples. A major plan of the research team of the Climate and Air Quality Taiwan Station (CATs) was the measurement of atmospheric nonmethane hydrocarbons. An analytical method has been development for the analysis of the individual nonmethane hydrocarbons in ambient air at ppb (v) and subppb(v) levels. The whole ambient air samples were collected in canisters and analyzed by GC-FID with $Al_2O_3$/KCl PLOT column. Our targeted for quantitative analysis 43 compounds that may be substantial contributors to ozone formation. The retention indices and molar response factors of some commercially available $C_2{\sim}C_{10}$ hydrocarbons were determined and used to identify and quantify air samples. A quality assurance program was instituted to ensure that good measurements were made by participating in the International Nonmethane Hydrocarbon Intercomparison Experiments (NOMHICE).

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.20 no.8
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• pp.547-555
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• 2008

The effects of paper properties such as density, air permeability, water vapor transmission rate on the thermal performance of plate-type enthalpy exchanger were experimentally investigated. Papers having different properties were made from the same pulp by calendering or refining. Enthalpy exchanger samples were made from the papers, and were tested according to the standard test procedure (KS B 6879). Effective efficiencies were obtained, which accounted for the air leakage between supply and exhaust streams. Results showed that paper density affected the sensible heat transfer of the samples. Sensible heat transfer increased with density of the paper. It was also shown that effective efficiency of latent heat transfer was approximately the same independent of the samples, which suggests that papers made of the same pulp show similar water vapor transmission characteristics independent of the degree of calendering or refining. Best performance was obtained for the sample having highest paper density and moderate water vapor transmission ratio.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.04a
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• pp.213-217
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• 2004

Laboratory scale study for an area of influence and flowing aspect of groundwater saturated zone was conducted for three sediment grains. On the AMG(Average Modal diameter Grains) 0.34, 1.38, 3.89mm diameter samples, the affected area of the aquifer were 15.2, 37.0, 30.0%/m2 each. Air flow for AMG 0.34mm diameter grain size provides indication of pattern of channelized air flow in saturated zone and expansion state in above saturated zone. For AMG of 1.38, 3.89mm diameter grains, air flow are pervasive air flow, forming a symmetrical cone of influence around the injection point. And also AMG 1.38, 3.89mm diameter samples show onset of collapse and approach to steady state in above saturated zone, respectively. In this study, optimal sites for in situ air sparging, may be grain diameters between about AMC 1.5～2.5mm diameter.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.4
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• pp.385-389
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• 2005

To understand the pollution level by polychlorinated biphenyls (PCBs) in ambient air of industrial area, PCBs concentrations were measured at Sihwa and Banwol industrial region, Korea. The concentrations of total PCB and WHO-TEQ ranged from 2,080 to $5820\;pg/m^3$ (median value is 2,760) and from 0.19 to $1.01\;pgTEQ/m^3$ (median value is 0.42), respectively. In terms of homologues composition the fraction of highly chlorinated biphenyls(from hexa-CB to deca-CB) were higher than the air samples of other regions such as jeonju and yokohama area. The cluster analysis was conducted to study the relation between the air samples and sources such as incinerator flue gases and Aroclor samples. The isomer fractions in the homologue were used as input variables. Based on the results, the industrial ambient air samples were divided from source samples with long Euclidian distance. This suggest that the ambient air samples of Sihwa and Banwol were not on the influence of Aroclor and incinerators. Therefore, further investigation on systematical air monitoring will be required to estimate the sources of PCBs in the above industrial areas.

• Korean journal of food and cookery science
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• v.13 no.5
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• pp.674-680
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• 1997

Volatile flavor components of fresh, shady air dried, and presteamed shady air dried Chamnamul (Pimpinella brachycarpa) were collected by simultaneous steam distillation-extraction method, and essential oils were analyzed by gas chromatography-mass spectrometry (GC/MS). Twenty five, 17 and 23 volatile flavor components were identified in essential oils extracted from the fresh, shady air dried, and presteamed shady air dried Chamnamul samples, respectively; however, the kinds of individual components and its percent content of the total volatiles were varied depending on samples. The principal components of Chamnamul were isobutanal, trans caryophyllene, trans ${\beta}$-farnesene, and ${\alpha}$-selinene. Terpenoid compounds reached 44.11%, 33.91% and 72.63% respectively in fresh, shady air dried, and presteamed shady air dried Chamnamul.

• Korean journal of food and cookery science
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• v.23 no.6
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• pp.800-809
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• 2007

To develope Hanbang beef jerky as health food, six kinds of beef jerky were prepared by adding sugar (A), licorice (B) and three kinds of spice extracts (clove: C, fennel fruit: D and Chungyang green pepper extract: E) and mixture of all extracts (F). The effects of the drying method and added spice extracts on the quality characteristics of the beef jerky were evaluated. In general, the air-blast dried beef jerky contained $31{\sim}33%$ moisture, $50.0{\sim}51.2%$ crude protein, $7.2{\sim}7.8%$ crude lipid and $3.0{\sim}3.3%$ crude ash. For the mineral content of the air-blast dried jerky, the most prevalent mineral was Na $(1540.08{\sim}1838.17$ mg%), followed by K, P, Mg, and Ca. The Ca content of the beef jerky was highest in the mixed extract group (88.53 mg%), and the lowest content was in sugar-added group (53.12 mg%). For the color properties, the L-value (lightness), a-value (redness) and b-value (yellowness) were higher in the air-blast dried beef jerky than in the hot air dried samples. The drying methods showed their greatest affect on the redness (a) for all six jerkies (p<0.001). For the preference by sensory evaluation, the beef jerky samples with added sugar (A) and licorice extract (B) had significantly higher scores than the beef jerky samples with the added spice extracts, for both of air-blast drying and hot air drying (p<0.05). Preference for the air-blast dried beef jerkies with added clove (C) and fennel fruits (D) were significantly higher, in terms of taste, color, softness and aftertaste as compared to the respective hot air dried jerkies (p<0.01). Considering all the obtained results, we concluded that licorice and spice extracts can be used as natural preservatives in the development of health foods and the air-blast drying method is recommended to improve the quality characteristics of beef jerky.

• Journal of Environmental Health Sciences
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• v.26 no.3
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• pp.18-24
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• 2000

The collection of PM10 samples were collected by a PM10 hi-vol. air sampler from June, 1998 through May, 1999 in Kunsan located at western coastal region of Korea. We obtained 84 samples during sampling period. Samples were analyzed to quantify the concentration of ionic and metallic components such as SO42-, NO3-, Cl-, NH4+, K+, Na+, Mg2+, Zn, Cd, Cr, Pb and Fe. Seasonal variations of the concentrations by wind directions of each component were studied. We found that PM10 concentration had the highest level in winter and the lowest level in summer. When the wind direction is from west to east, the concentration of most ionic and metallic species were higher compared to reverse direction. That implied the effect of air pollutants from industrial area. Also, substantial amount of Na+ and Cl- were observed, which was assumed to the effect from the sea.

• Journal of Magnetics
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• v.15 no.4
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• pp.190-193
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• 2010

The design of joints in a transformer core significantly affects the transformer's efficiency. Air gaps cause variations in the flux distribution at the joints of the laminations, which depend on the geometry. Two similar samples consisting of electrical steel strips and amorphous ribbons were made. The spatial flux distributions were determined using an array of search coils for each sample. 2D models of these samples were created and examined by finite element analysis. The magnetic flux distribution for each lamination in the samples was computed. The results show that the flux density in amorphous ribbons above and below the air gap starts to approach saturation at lower flux density levels than for electrical steel. The flux density measured using the search coil under the air gap is increased in amorphous ribbons and decreased in the electrical steel with increasing frequency.

• Mycobiology
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• v.51 no.4
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• pp.210-215
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• 2023

The aim of this study was to characterize a new fungal species, Acremonium conglutinatum, isolated from air samples collected in Wando, South Korea. Phylogenetic analysis based on the internal transcribed spacer and large subunit regions revealed its unique position within the genus Acremonium. The isolated strain displayed distinct morphological characteristics, including ellipsoid or bent-ellipsoid conidia formed in clusters on the phialides. These features differentiate the new species from closely related species within the genus. This study describes the morphological and molecular characteristics of A. conglutinatum and emphasizes its phylogenetic relationships with other Acremonium spp. The identification of this novel species contributes to our understanding of the diversity and ecological role of Acremonium.