• Journal of the Mineralogical Society of Korea
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• v.23 no.3
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• pp.227-234
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• 2010

We investigated the effect of dry grinding of laterite on the extraction of nickel and cobalt. The major chemical compositions of the sample for this work were $SiO_2$, $Fe_2O_3$ and MgO. The sample contained 0.81% Ni and 0.02% Co. The major minerals of the sample were lizardite and quartz with minor amounts of forsterite and enstatite. The mean particle size, specific surface area and density of the ground sample decreased with increasing grinding time, while the amorphization of lizardite increased as identified by XRD analysis. The grinding enabled the extraction ratio of Ni and Co to increase by the breakdown of Mg-OH bonding in the lizardite structure. However, physical properties of quartz were not changed by grinding. The extraction ratio of Ni and Co increased with increasing grinding time. Approximately 80% of Ni and Co were extracted regardless of the kind of acid solutions when the sample was ground for 60 minutes.

• Korean Journal of Food Science and Technology
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• v.32 no.1
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• pp.37-41
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• 2000

This study has been carried out to investigate the chemical composition of Acorus calamus L., a wild plant (Chang Po) which has long been used as a medicine or a hair rinse in Korea and China. Potassium was found to be the most predominant mineral in leaf and root, followed by calcium, magnesium, and phosphorus, in a decreasing order. Contents of potassium in leaf and root account for 54a.65 mg% and 242.87 mg%, respectively. Contents of these minerals in leaf were higher value than that in root. Glucose and fructose were found to be the major free sugars in leaf and root. Malic acid was the most abundant organic acid of leaf and root, and followed by citric acid. Fourteen different kinds of fatty acids were identified from the leaf and root. Content of unsaturated fatty acids. such as linolenic, and linoleic acid ware higher than that of saturated fatty acids. Content of total amino acids was 3 times higher in leaf than that in root. Leucine was the major amino acid in leaf and glutamic acid in root.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.3
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• pp.539-542
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• 2002

To evaluate a flower of rose, Rosa hybrids L. as a new food material, its chemical composition was analysed. The contents of crude protein, crude fat, crude ash and crude fiber in rose petals were 16.3, 2.9, 5.4, 16.1% on dry basis, respectively. Free sugars showed 74.3 mg/g of fructose, 49.6 mg/g of glucose and 16.6 mg/g of xylose. The contents of ${\beta}$-carotene and ascorbic acid were 205.2 ug/100 g and 129.5 mg/100 g, respectively. The major minerals of rose petals were K, P, Mg, Ca, Na and Fe, and among them K was the most abundant as 1,981.7 mg/100 g. The major amino acids were aspartic acid as 4,007.3 mg/100 g, glutamic acid as 1,114.8 mg/100 g, lysine as 672.6 mg/100 g and leucine as 661.0 mg/100 g. Fatty acids were mainly unsaturated fatty acids as 76.3%.

• Korean Journal of Food Science and Technology
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• v.30 no.4
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• pp.827-831
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• 1998

Effects of pre-pressing condition on quality of pear juice were investigated. Three different types of pressed pear juices such as heated-and-pressed pear juice (HPP), blanched-and-pressed pear juice (BPP), and thawed-and-pressed pear juice (TPP) were prepared. The yield and content of soluble solids in HPP were 78% and $15.0^{\circ}Bx$ which were higher than the other treatments, respectively. Acidity and pH of all the samples were about 0.2% and 4.9, respectively. Major free sugars and organic acids in HPP, BPP, and TPP were fructose and malic acid, respectively. Major soluble minerals were K, P and Mg, and miner ones were Na and Fe. HPP showed a lowest L value, but had a highest taste.

• Journal of the Korean Society of Food Culture
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• v.11 no.5
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• pp.635-641
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• 1996

As a basic study for preparing pine sprout tea, chemical components in pine sprouts and pine needles were analyzed as follows: In proximate composition the contents of most components except for crude fat were different between in pine sprouts and pine needles. Moisture content in pine sprouts was higher than that in pine needles. Calcium and potassium were major minerals contained in pine sprouts and needles, and their contents in pine needles picked in December were higher than those picked in June. Soluble tannin and vitamin C contents in leaf part of pine sprouts were much higher than those in stem part and their contents in pine needles were increased according to their growth. Free sugars like fructose, glucose and sucrose were contained in both pine sprouts and needles, and their contents in pine sprouts were higher in stem part as compared that in leaf part. Although fourteen kinds of amino acids were detected in pine sprouts and pine needles, their contents were extremely low. Amino acid composition between pine sprouts and pine needles was different each other, but major amino acids contained in them were same, those are acidic amino acids such as aspartic acid and glutamic acid. Amino acid contents in pine needles were increased according to the growth. In fatty acid composition in leaf part of pine sprouts, saturated fatty acid contents were higher than unsaturated fatty acid contents, but in stem part unsaturated fatty acid contents were higher. In pine needles the amount of saturated fatty acid was increased with the growth, but the amount of unsaturated fatty acid was rather decreased.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.51 no.6
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• pp.623-631
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• 2018

The present study investigated the food component characteristics of a bone-softened mackerel Scomber japonicus product (FC-M). The proximate composition of the FC-M was 57.4% moisture, 25.2% crude protein, 14.1% crude lipid, and 2.7% ash. The energy in the FC-M was 241.5 kcal/100 g, which corresponds to 8.9-16.1% of the daily energy intake recommended for Koreans ${\geq}6$ years of age. Regardless of type of taste, there were no significant differences in taste intensity when the FC-M was compared to a control (canned mackerel) but the odor intensity was significantly higher. Although there were no significant differences in hardness, the Hunter color values of redness and yellowness were significantly lower than those of the control. The sensory score for the FC-M was significantly superior to that of the control. The total amino acid content in the FC-M was 24.12 g/100 g and the major amino acids were aspartic acid, glutamic acid, leucine, and histidine. The major fatty acids in the FC-M were 16:0, 18:1n-9, 20:5n-3, and 22:6n-3 and the FC-M was a good source of minerals.

• Journal of the Korean Society of Food Culture
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• v.25 no.4
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• pp.480-486
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• 2010

Taking vitamin and mineral supplements is increasingly common with the rapid economic growth. The aim of this study was to determine the prevalence of vitamin and mineral supplement use among adults aged 20 or older from the third Korean National Health and Nutrition Survey data and to explore the effect of sociodemographic and lifestyle factors as well as nutrient intake on taking supplements. People who had participated in both a health questionnaire and a nutritional survey were selected, and 2,871 men and 3,555 women were finally included in this analysis. Both men and women with a higher level of education, those residing in a metropolitan area, and those with higher income were more likely to take supplements. Health behaviors were not significantly associated with taking supplements. Mean nutrient intake of all nutrients except energy intake was not significantly different in men or women taking supplements after adjusting for age, education, marital status, resident area, smoking, and energy intake. Compared to Dietary Reference Intake (DRI) for Koreans, most vitamins and minerals, except vitamin $B_2$ and calcium, were consumed at higher than the Recommended Intake (RI) without supplements. In conclusion, taking supplements such as vitamin $B_2$ and calcium may promote health and prevent disease. However, the type and frequency of other vitamin and mineral supplements consumed should be considered with caution.

• Korean Journal of Soil Science and Fertilizer
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• v.24 no.2
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• pp.79-85
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• 1991

This study reports on the physical and chemical properties of the whole soils (<2mm) derived from five major rocks of granite, granite-gneiss, limestone, shale, and basalt in Korea. The properties were considered from the kind and frequency distribution of rock-forming minerals in the parent rocks. In particle size distribution, sand fractions were high in the soils from granite-gneiss, silt fractions mainly, in the residual soils from limestone, shale, and basalt. And clay fractions were particularly high in the colluvial soil from limestone and the old alluvial soil from basalt. pH, extractable Ca and Mg, and cation exchange capacity of the soils derived from limestone might be considered to be high due to the presence of sand and/or silt-sized calcite and dolomite inherited from the parent rocks. However, the soils derived from granite and granite-gneiss, being abundant in feldspars, quartz, and micas, showed a tendency to the contrary. A soil from shale composing of high quartz tended to have pH. extractable Ca, base saturation, and low exchangeable Al. In total element analysis, the soils derived from parent rocks with high contents of (i) orthoclase and micas, (ii) biotite, primary chlorite, and augite, and (iii) carbonate minerals and plagioclase as a rock-forming mineral showed a tendency to decrease the contents of $K_2O$, $Fe_2O_3$ and MgO, and CaO in comparison with those of their parent rocks.

• Journal of the Korean Society of Groundwater Environment
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• v.5 no.1
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• pp.10-20
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• 1998

Heavy metal contamination in subsurface soils and stream sediments at the Suggok mine area were investigated on the basis of major, trace and rare earth elements geochemistry and mineralogy. The Sanggok mine area is mainly composed of Cambro-Ordovician carbonate rocks. The mine had been mined for Pb-Zn-Fe and Au- Ag, but already closed in past. For major elements, especially Fe (mean value=18.58 wt.%) and Mn (mean value=4. 18 wt.%) are enriched in soils, and the average enrichment indices of soils and sediments are 6.84 and 1.54, respectively. The average enrichment index of rare earth elements are 0.92 of mining drainage sediments and 0.52 of subsurface soils on the tailing dam. Concentrations of minor and/or environmental toxic elements in those samples range from 29 to 3400 for As,1 to 11 for Cd, 35 to 292 for Cu, 50 to 1827 for Pb, 1 to 22 for Sb and 112 to 2644 for Zn. Extremely high concentrations (mean values) are found in subsurface soils on the tailing dam (As=2278, Cd=7, Cu=206, Pb=1372, Sb=14 and Zn=2231 ppm, respectively). Average enrichment index normalized by composition of non-mining drainage sediments is 2.42 in mining drainage sediments and 25.47 in subsurface soils on the tailing dam. Based on EPA value, enrichment index of toxic elements is 0.53 in non-mining drainage sediments, 1.84 in mining drainage sediments and 23.71 in subsurface soils on the tailing dam. As a results from X-ray powder diffraction method, mineral composition of soils and sediments near the mine area varied in part, and are calcite, dolomite, magnesite, quartz, mica, chlorite and clay minerals. With the separation of heavy minerals, soils and sediments of highly concentrated toxic elements included some pyrite, arsenopyrite, sphalerite, galena, goethite and hydroxide minerals on the polished sections.

• The Journal of the Petrological Society of Korea
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• v.21 no.2
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• pp.263-275
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• 2012

Jurassic Daebo biotite granites, known as one of the main stone resources in the country, are widely and away distributed in the Pocheon and Yangju areas of the mid Gyeonggi massif. The objects of the study are mainly to reveal the unique characteristics of grain size, rock color, mineral composition, physical property and fracture system from the above biotite granites. Biotite granites from the Pocheon area (PG) and Yangju area (YG) are represented by coarse-grained and light gray, and medium to coarse-grained and grayish to light gray, respectively. In modes, main minerals of Qz+Af+Pl (quartz+alkali feldspar+plagioclase) are more increased in the PG, and accessories of biotite are more increased in the YG, which differences can cause the PG more bright light gray than the YG. Specific gravity (SG) shows somewhat more increasing in the YG than the PG. These differences can be caused by more increasing in biotite contents of higher specific gravity compared to the major minerals in the former than the latter. Absorption ratio (AR) and porosity (PR) of the PG and YG show the same values of 0.33 % and 0.86 %, respectively. In the correlations, PR vs SG and AR vs PR show gradually negative and distinctly positive trends, respectively. Compressive strength (CS) and tensile strength (TS) show increasing in the PG (CS: 1,775 $kg/cm^2$, TS: 87 $kg/cm^2$) than the YG (CS: 1,647 $kg/cm^2$, TS: 79 $kg/cm^2$). These strength characteristics could be attributed to the inherent rock textures of them. Abrasive hardness (AH) also shows a little increasing in PG, which can be caused by increase in quartz contents having higher hardness than the other major minerals. Orientations of fracture sets from the PG and YG were compared with those of vertical rift and grain planes in Mesozoic granites of the country. From the overlapped diagram, the distribution pattern between fracture sets and above vertical planes suggests that microcrack systems developed in Mesozoic granites in Korea occur also in the Daebo biotite granite bodies of the mid Gyeonggi massif. From the relation diagram showing the characteristics of fracture patterns for the above two area, PG and YG may have more potentiality for dimension and non-dimension stone resources, respectively.