• Journal of Korean Society of Environmental Engineers
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• v.29 no.1
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• pp.113-125
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• 2007

To know the differences in ionic compositions in rain and snow as well as snow influence on the chemical characteristics of winter precipitation, precipitation samples were collected by the wet-only automatic precipitation sample, in winter(November-February) in the Iksan located in the northwest of Chonbuk from 1995 to 2000. The samples were analyzed for concentrations of water-soluble ion species, in addition to pH and electrical conductivity. The mean pH of winter precipitation was 4.72. According to the type of winter precipitation, the mean pH of rain was 4.67 and lower than 5.05 in snow. The frequencies of pH below 5.0 in rain were about 73%, while those in snow were about 30%. Snow contained 3 times higher concentrations of sea salt ion components originated from seawater than did rain in winter, mainly $Cl^-,\;Na^+$, and $Mg^{2+}$. Neglecting sea salt ion components, $nss-SO_4^{2-}$ and $NO_3^-$ were important anions and $NH_4^+$ and $nss-Ca^{2+}$ were important cations in both of rain and snow. Concentrations of $nss-SO_4^{2-}$ was 1.3 times higher in rain than in snow, while those of $nss-Ca^{2+}$ and $NO_3^-$ were 1.5 and 1.3 times higher in snow, respectively. The mean equivalent concentration ratio of $nss-SO_4^{2-}/NO_3^-$ in winter precipitation were 2.4, which implied that the relative contribution of sulfuric and nitric acids to the precipitation acidity was 71% and 29%, respectively. The ratio in rain was 2.7 and higher than 1.5 in snow. These results suggest that the difference of $NO_3^-$ in rain and snow could be due to the more effective scavenging of $HNO_3$ vapor than particulate sulfate or nitrate by snow. The lower ratio in snow than rain is consistent with the measurement results of foreign other investigators and with scavenging theory of atmospheric aerosols. Although substantial $nss-SO_4^{2-}$ and $NO_3^-$ were observed in both of rain and snow, the corresponding presence of $NH_4^+,\;nss-Ca^{2+},\;nss-K^+$ suggested the significant neutralization of rain and snow. Differences in chemical composition of non-sea salt ions and neutralizing rapacity of $NH_4^+,\;nss-Ca^{2+}$, and $nss-K^+$ between rain and snow could explain the acidity difference of rain and snow. Snow affected that winter precipitation could be less acidic due to its higher neutralizing rapacity.

• Journal of Animal Science and Technology
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• v.45 no.2
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• pp.251-264
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• 2003

This study was conducted to make on-site survey on the output pattern and utilization situation of 19 by-products selected, to evaluate their nutritional characteristics, to find out a reliable index with which digestion of by-products can be predicted on the basis of chemical compositions analyzed and to diagnose the risk of using book values in the absence of the actual values analyzed for diet formulation. Production and utilization situations of by-products were quite various. Nutritionally, fruit processing by-products such as apple pomace (AP), pear pomace (PP), grape pomace (GP), and persimmon peel (PSP), and bakery by-products (BB) were classified as energy feeds. Soybean curd meal (SCM), animal by- products such as blood (BD), feather meal (FM) and poultry by-products (PB), and activated milk processing sludge (AMS) were classified as protein feeds. Soy hulls (SH), spent mushroom compost (SMC), barley malt hulls (BMH), waste paper (WP) and broiler litter (BL) were classified as roughage. Rumen contents (RC) and restaurant food waste (FW) were nutritionally analogous to complete diets for cattle and swine, respectively. Compared to soybean meal (SBM), BD and FM contained high (P<0.05) levels of amino acids and barley malt sprouts (BMS), AMS and FW contained low (P<0.05) levels of amino acids. Enzymatic (pepsin) digestibilities of proteinaceous feeds ranged between 99 and 66%. In vitro DM digestibility was high (P<0.05) in the order of FW, BB, AP, SH, PP, PSP, BMH, BMS, SCM, GP, RC, PB, BL, WP, SMC, AMS, FM and BD. In vitro DM digestibility had the highest correlation (r=0.68) with nonfibrous carbohydrate among chemical components. Differences between analyzed values of chemical components and book values were considerable. Caution is required in using book values when large amount of by-products are used in diets.

• Korean Journal of Soil Science and Fertilizer
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• v.35 no.3
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• pp.145-152
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• 2002

The composition of primary minerals in the rocks and secondary minerals of clay fractions of the soil developed on the cinder cones in the foot of Halla Mt., Jeju Island was investigated. The effects of parent materials on the physico-chemical properties and mineralogical characteristics were evaluated by XRD, DTA with the chemical composition of $H^+$ saturated clays. The main rock-forming minerals of a residual cinder cones were plagioclase with subsidiary minerals of hematite, gibbsite and quartz in the red cinder cone and of augite, quartz, feldspars and olivine in black cinder cone. It is demonstrated that ignition loss and sesquioxides content were higher in the red cinder soil than black cinder, which was resulted in the intermittent eruption of volcanic activity. For the chemical analysis of whole soils, $SiO_2/Al_2O_3$ ratio was increased from 2 to 3, but Ignition loss is decreased and $K_2O$ content are very low with increasing the soil depth in regard to the composition and kinds of clay minerals. No clay formation from micas mineral were in volcanic ashes. Dominant clay minerals of the cinder cone soils as a black and red cinder cone soil were allophane with some quartz and feldspars, while vermiculite, illite, kaolin were coexisted as a subsidiary minerals. But the red cinder cones soils had more hematite and gibbsite of the clay fractions than the black soils with magnetite. The exothermic pick of DTA at about $660^{\circ}C$ for cinder cone soils might be corresponded the oxidation magnetite to hematite reation. With regarding to the compositions of mineral detected by X-ray diffractogram and the properties of minerals by D.T.A thermogram, the dominant clay mineral was allophane of the cinder cone soils with some ferrous compounds, red colour of the cinder cone soils which are originated in hematite.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.7
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• pp.962-968
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• 2011

The objective of this study was to investigate the chemical components and quality characteristics of three waxy corn varieties (Heukjinju, Ilmi, and Yeonnong1) harvested by conventional cultivation (CC) and environmentally-friendly cultivation (EFC). Crude ash content of the three corn varieties was higher, but not significant, in CC than EFC. Crude fat and protein contents in Heukjinju were higher in EFC, and amylose content was significantly higher (p<0.001). Free sugar, minerals, and fatty acid composition patterns varied according to the cultivation method. Vitamin E contents in the Heukjinju and Yeonnong1 cultivars were higher in CC than EFC. Total polyphenol content of waxy corns on EFC and CC were 175.28 and 204.00 mg/100 g, respectively, in the Heukjinju cultivar (p<0.01), and 148.64 and 158.42 mg/100 g, respectively, in the Ilimi cultivar, and 123.24 and 128.30 mg/100 g, respectively, in the Yeonnong1 cultivar. 2,2-Diphenyl-1-picrylhydrazyl radical scavenging activity on EFC and CC was 1.51 and 1.76 in Heukjinju cultivar (p<0.05), 0.29 and 0.34 in Ilmi cultivar (p>0.05), and 0.39 and 0.42 mg trolox eq/g in Yeonnong1 cultivar (p>0.05), respectively. However, 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonate) radical scavenging activity was higher in CC than EFC.

• Journal of the Korean Wood Science and Technology
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• v.43 no.6
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• pp.851-860
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• 2015

The objective of this study was to manufacture the wood based roughage using lumber from thinning of oak and pitch pine (Pinus rigida). And the study also aimed to investigate a feed value evaluation of wood based roughages. To investigate the optimization condition of steam-digestion treatment for roughage, the wood chips of oak and pitch pine were steam-digestion treated at $160^{\circ}C$ under pressure 6 atm depending on treatment times (60 min, 90 min and 120 min) followed by the content of essential oils analyzed. The essential oil content of steam-digestion treated roughages for 90 min and 120 min were under 0.1 mL/kg. The evaluation of feed value was carried out from steam-digestion treated roughages for 90 min through feed chemical composition analysis, NRC (National research Council) modeling, ruminal degradability analysis and relative economic value analysis. The feed chemical compositions including DM (dry mater), CP (crude protein), EE (ether extract), NDF (neutral detergent fiber), ADF (acid detergent fiber), ADL (acid detergent lignin), NFC (nonfiber carbohydrate) in oak roughage were 95.4, 1.36, 3.11, 90.05, 83.85, 17.33, 6.50%, respectively, and in pitch pine roughage were 94.37, 1.33, 5.48, 87.89, 86.88, 30.56, 6.32%, respectively. Both roughages showed low level of protein and very high level of NDF. The TDN (total digestible nutrient) levels using NRC (2001) model in oak and pitch pine roughages were 40.55, 31.22%, respectively. The ruminal in situ dry matter degradability was higher in oak roughage (23.84%) than in pitch pine roughage (10.02%). The economic values of oak and pitch pine rough-ages were 235, and 210 \, respectively.

• the MEAT Journal
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• s.36 summer
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• pp.61-71
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• 2009

The aim of this work was to analyze the effects of salt and NaNO2 on weight loss, proximate compositions, chemical parameters and texture characteristics of dry-cured ham processed using Korean methods. Four different treatments were considered: The H8 group of 3 hams (11.30 kg) was salted with 9.2 g/kg salt (w/w) (high salt batch), the HS+NaNO2 group of 3 hams (10.65 kg) was salted same as HS group and added 100 ppm NaNO2. The LS group of 3 hams (11.42 kg) was salted with 6.2 g/kg salt (w/w) (Low salt batch), the LS+NaNO2 group of 3 hams (10.62 kg) was salted same as L8 group and added 100 ppm NaNO2. The highest weight losses took place at the drying stage (27.46, 28.25, 26.99, and 28.42%). However, there were no significant differences in the weight losses between treatments (p>0.05). The moisture content was significantly affected with addition of NaNO2 (p<0.05), the L8 hams had significantly higher moisture content than HS + NaNO2 and L8 + NaNO2 (p<0.05). The level of salt and NaNO2 did not affect the fat, protein and ash contents. The hardness and chewiness in biceps femoris muscle from L8 hams were significantly lower than in the muscles from HS + NaNO2 hams (p<0.05). The NaNO2 did not affect the texture characteristics of dry-cured hams. The processing conditions significantly affected the chemical parameters of biceps femoris muscle (p<0.05). The water activity in biceps femoris muscle from L8 hams was significantly higher than in muscles from HS and H8+NaNO2 hams (p<0.04). The salt content in biceps femoris muscles from LS + NaNO2 hams was significantly lower than in the muscles from HS and HS + NaNO2 hams (p<0.05). The NaNO2 treatment did not affect the NaNO2 content in biceps femoris muscles (p>0.05). The processing conditions did not significantly affect the lightness (L), redness (a), and $h^{\circ}$ of biceps femoris muscles (p>0.05). The yellowness (b) and chroma in biceps femoris muscle from HS + NaNO2 hams were significantly higher than in the muscles from HS and LS hams.

• Korean Chemical Engineering Research
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• v.55 no.1
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• pp.93-98
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• 2017

This experiment investigated characteristic changes in a $Cu_2ZnSnS_4$(CZTS) solar cell by applying a $Zn(O_x,S_{1-x})$ butter layer with various compositions on the upper side of the absorber layer. Among the four single layers such as $Zn(O_{0.76},S_{0.24})$, $Zn(O_{0.56},S_{0.44})$, $Zn(O_{0.33},S_{0.67})$, and $Zn(O_{0.17},S_{0.83})$, the $Zn(O_{0.76},S_{0.24})$ buffer layer was applied to the device due to its bandgap structure for suppressing electron-hole recombination. In the application of the $Zn(O_{0.76},S_{0.24})$ buffer layer to the device, the buffer layer in the device showed the composition of $Zn(O_{0.7},S_{0.3})$ because S diffused into the buffer layer from the absorber layer. The $Zn(O_{0.7},S_{0.3})$ buffer layer, having a lower energy level ($E_V$) than a CdS buffer layer, improved the $J_{SC}$ and $V_{OC}$ characteristics of the CZTS solar cell because the $Zn(O_{0.7},S_{0.3})$ buffer layer effectively suppressed electron-hole recombination. A substitution of the CdS buffer layer by the $Zn(O_{0.7},S_{0.3})$ buffer layer improved the efficiency of the CZTS solar cell from 2.75% to 4.86%.

• Korean Chemical Engineering Research
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• v.54 no.2
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• pp.213-222
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• 2016

Solubility data of hydrogen sulfide ($H_2S$) and methane ($CH_4$) in two kinds of ionic liquids with the same anion: 1-ethyl-3-methylimidazolium trifluoromethanesulfonate ([emim][TfO]) and 1-butyl-1-methylpyrrolidinium trifluoromethanesulfonate ([bmpyr][TfO]) are presented at pressures up to about 30 MPa and at temperatures between 303 K and 343 K. The gas solubilities in ionic liquids were determined by measuring the bubble point pressures of the gas + ionic liquid mixtures with various compositions at different temperatures using a high-pressure equilibrium apparatus equipped with a variable-volume view cell. The $H_2S$ solubilities in ionic liquid increased with the increase of pressure and decreased with the increase of temperature. On the other hand, the $CH_4$ solubilities in ionic liquid increased significantly with the increase of pressure, but there was little effect of temperature on the $CH_4$ solubility. For the ionic liquds [emim][TfO] and [bmpyr][TfO] with the same anion, the solubility of $H_2S$ as a molality basis was substantially similar, regardless of the temperature and pressure conditions as a molar concentration basis. Comparing the solubilities of $H_2S$ and $CH_4$ in the ionic liquid [emim][TfO], the solubilities of $H_2S$ were much greater than those of $CH_4$. For the same type of ionic liquid, the solubility data of $H_2S$ and $CH_4$ obtained in this study were compared to the solubility data of $CO_2$ from the literature. When compared at the same pressure and temperature conditions, the $CO_2$ solubility was in between the solubility of $H_2S$ and $CH_4$.

• Applied Biological Chemistry
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• v.28 no.3
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• pp.202-208
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• 1985

The significant chemical constituents estimating the quality of green tea were compared and analyzed in the tea shoots of native Korean tea plants. The tea shoots of different varieties among native tea plants were plucked in Waun-ri, Yongjang-ri, others in eight tea-growing places, and Yabukita, for the comparison, which is excellent Japanese variety. The contents of Yongjang-ri tea shoots were 0.55% lower in total nitrogen, 41.44mg% lower in vitamin C and 0.56% higher in tannin than the average of the other eight places. The contents of ash, caffeine and water extract showed no difference between the tea shoots. Tea shoots of Waunri had similar compositions compared with those of Yabukita and other eight places in the chemical constituents. It is considered that the tea loaves in Yongjang-ri would be different variety comparing with other eight places in the view of characters and constituents. And it is thought that tea loaves in Waun-ri would be the large leaf variety of same genealogy because tea loaves in Waun-ri was different from the other eight places in characters, but was similar to in constituents.

• Korean Journal of Soil Science and Fertilizer
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• v.38 no.5
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• pp.259-268
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• 2005

Most of the tailings have been left without any management in their mines and have become the main source of serious environmental problems in nearby groundwater, stream and cultivated lands. To compare fractionation and potential mobility of heavy metals in tailings and paddy soils near abandoned 10-metalliferous mines in Korea, the distribution and chemical fractions of heavy metal and their mobility in relation to chemical compositions were investigated. The pollution index of heavy metal in mine tailing calculated with the permissible levels were in the order Cheongyang>Dogok>Beutdeun>Baegwoul mine, which were considered sufficient to raise environmental problems. The rates of 0.1M-HCl extractable Cd, Cu, Pb, Zn, and Ni to total content in paddy soils were 49.1, 50.7, 26.8, 18.4 and 2.9%, respectively, and their rates of heavy metals in paddy soils were higher than that of mine tailing. Dominant chemical forms of heavy metals in tailings were sulfide and residual form (63-91%), specially, the exchangeable portion of Cd (21%) was relatively higher than that of other metals in paddy soils. The mobility factor of heavy metals in tailings and paddy soils was in the order Cd>Zn>Cu>Pb, and the mobility factor in tailing varied considerably among the mines. The potential mobility of heavy metals in tailings showed significant positive correlation with water-soluble $Al^{3+}$ and $Fe^{3+}$ contents, while in paddy soils, it correlated negatively with soil pH values.