• Applied Chemistry for Engineering
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• v.23 no.4
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• pp.367-371
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• 2012

Waste printed circuit boards (WPCBs) contain valuable metals such as Cu, Ni, Au, Ag, and Pd. For an effective recycling of WPCBs, it is essential to recover the valuable metals. In recent years, recycling processes have come to be necessary for separating noble metals from WPCBs due to an increasing amount of electronic device wastes. However, it is well known that glass reinforced epoxy resins in the WPCBs are difficult materials to separate into elemental components, namely metals, glass fibers and epoxy resins in the chemical recycling process. $K_3PO_4$ as a catalyst in dimethylformamide (DMF) and N-Methyl-2-pyrrolidone (NMP) was used to depolymerize epoxy resins for recovering metallic and non-metallic components from WPCBs. Reactions of WPCBs were carried out at temperatures $160{\sim}200^{\circ}C$ for 2~12 h. The recycled glass fiber from WPCBs was analyzed by thermogravimetric analyzer (TGA) and evaluated the degree of solubility of the epoxy resin for separation efficiencies of the WPCBs.

• Mycobiology
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• v.43 no.4
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• pp.423-434
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• 2015

The study was conducted to compare the effects of different agro-wastes on the growth, yield, and nutritional composition of oyster mushrooms Pleurotus ostreatus (PO) and Pleurotus cystidiosus (PC). Seven substrate formulas including sawdust (SD), corncob (CC), sugarcane bagasse (SB) alone and in combination of 80 : 20, 50 : 50 ratio between SD and CC, SD and SB were investigated. The results indicated that different substrate formulas gave a significant difference in total colonization period, characteristics of fruiting bodies, yield, biological efficiency (BE), nutritional composition and mineral contents of two oyster mushrooms PO and PC. The results showed that increasing CC and SB reduced C/N ratio, and enhanced some mineral contents (Ca, P, and Mg) of substrate formulas. The increased amount of CC and SB of substrate formulas enhanced protein, ash, mineral contents (Ca, K, Mg, Mn, and Zn) of fruiting bodies of both mushrooms. Substrates with 100% CC and 100% SB were the most suitable substrate formulas for cultivation of oyster mushrooms PO and PC in which they gave the highest values of cap diameter, stipe thickness, mushroom weight, yield, BE, protein, fiber, ash, mineral content (Ca, K, and Mg) and short stipe length. However, substrate formula 100% CC gave the slowest time for the first harvest of both mushrooms PO and PC (46.02 days and 64.24 days, respectively). It is also found that the C/N ratio of substrate formulas has close correlation with total colonization period, mushroom weight, yield, BE and protein content of mushroom PO and PC.

• Resources Recycling
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• v.14 no.5 s.67
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• pp.32-39
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• 2005

Leaching behavior of nickel contained in waste Multi-Layer Ceramic Capacitor (MLCC) was investigated using a batch reactor. The effects of acid type, acid concentration, leaching temperature, particle size, and reaction time on the extraction of nickel metal from waste MLCC were examined. As a result, 97% of nickel contained in waste MLCC was leached out in 30 min at the temperature of $90^{\circ}C$ under the condition of $HNO_3$ concentration 1N, solid/liquid ratio 5 g/L and particle size $-300/+180{\mu}m$. It was also found that a Jander equation was useful to fit well the leaching rate data. The rate of nickel leaching is controlled by pore diffusion in $BaTiO_3$ layer and has an activation energy of 37.6 kJ/mol (9.0 kcal/mol).

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 1993.03a
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• pp.15.2-15
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• 1993

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 1993.03a
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• pp.9.2-9
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• 1993

• Journal of Ginseng Research
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• v.22 no.4
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• pp.294-298
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• 1998

This study was conducted to investigate the effects of growth characteristics and mineral contents of ginseng seedling grown in different locations on ginseng growth and root yield. Ginseng seedling produced in 16 farmers' field at the semi-Yangjik seedbed were planted and cultivated in a field with same cultural practices. Missing plant was increased with increased year of ginseng age, especially severe at 5-year-old ginseng. Rate of missing plant was different among the origins of the seedling, even with the same weights. Negative correlation was noted between the missing rate of 3-year-old ginseng plants and NH4-N content of the seedling, but positive correlation between the missing rate and K2O and Ca contents of the seedling. Root yield of 6-year-old ginseng was also affected by the origins of ginseng seedlings. Root yield was high in ginseng plant from 0.6∼0.9 g see dings compared to those from over 0.9 g seedlings.

• The Korean Journal of Ecology
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• v.15 no.4
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• pp.345-354
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• 1992

Allocation patterns of energy and mineral elements were investigated with phaseolus multiflorus grown in the environmental gradients. The result showed different energy allocation patterns according to relative light intensities and nutrients. The optimal switching time of energy allocation from vegetative to resproductive growth was delated as decreasing relative light intensity. The switch of the shift to reproduction was timed earlier in phosphorus treatment and delayed in nitrogen treatment. Analyzing the mineral elements to various organs, patterns of energy allocation were different from those of mineral allocation. There was no significant difference for allocation patterns in relative light intensity gradients. it was shown that n and p were distributed over the reproductive organs, k mainly in stems, ca in leaves and na in roots. mg was evenly distributed in each organs.

• Journal of Food Hygiene and Safety
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• v.1 no.2
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• pp.177-179
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• 1986

ABSTRACT$.$Seven species of mushrooms (Sarcodon asparatus, Agaricus bisporus. Calocybe gambosa, Len tin us ,edodes.Ramariabotrytis.Pleurotus ostreatus and Tricholoma matsutake) produced in Korea were investigated on their mineral contents mainly by using Inductively coupled plasma-technique. The obtained results are summerized as follows: 1) Fe, N a and Zn are relativel highly contained in almost all mushrooms tested in this study. 2) Harmful elements such as Cd, Hg. Pb and As, were found only in trace amounts. 3) Sb, Se and Sn were not detected in all mushrooms.hrooms.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.6
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• pp.862-866
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• 2016

Common stalked barnacle Pollicipes mitella is a filter-feeding crustacean that attaches itself to the surfaces of rocks in the ocean intertidal zone. Pollicipes mitella is one of about a dozen species of goose barnacle that are gathered commercially for human consumption. In Portugal and Spain, they are a widely consumed and expensive delicacy known as "Percebes (Pollicipes pollicipes )". However, common stalked barnacle is less popular in Korea, and information on its nutritional component is not yet available. In the present study, we analyzed the proximate and fatty acid compositions and mineral content of common stalked barnacle (muscle and cirrus). The muscle and cirrus of common stalked barnacle were 15.1% and 14.3% protein, and 3.31% and 1.81% lipid, respectively. The prominent fatty acids in the muscle and cirrus were 22:6n-3 (docosahexaenoic acid, DHA), 16:0, 20:5n-3 (eicosapentaenoic acid, EPA), 18:0, 18:1n-9, 16:1n-7 and 14:0. In particular, common stalked barnacle contained high levels of n-3 polyunsaturated fatty acids, such as DHA (25.4-25.6%) and EPA (14.7-15.1%), and low levels of the n-6 fatty acid, 20:4n-6 (1.2-1.3%). Common stalked barnacle contained a relatively large amount of Zn (10-42 mg/100 g) in its muscle and cirrus.

• Journal of Nutrition and Health
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• v.38 no.10
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• pp.827-835
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• 2005

The purpose of this study was to investigate the relation among mineral intakes, blood pressure, and blood lipids for health management of Korean adults over 20 years old. Subjects were recruited from the district where they lived, which included rural (Yoju, n = 137) , coastal (Taean, n = 100) , and urban district (Suwon, n : 117) . hnthropornekical measurement, blood pressure measurement, dietary intake assessment using 24-hour recall method, and blood collection and analysis of blood lipids were conducted. The average age, height, weight, and BMI were 54.1 years, 168.5 cm, 67.3 kg, and 24.5 kg/$m^{2}$ for men and 53.9 years,153.8 cm,59.2 kg, and 25.0 kg/$m^{2}$ for women, respectively. The mean daily intakes of total food and energy were 1219.1 g and 1740.9 kcal for men and 1071.3 g and 1432.6 kcal for women. The mineral intakes of men and women were 448.5 mg and 400.4 mg for calcium,955.3 mg and 803.7 mg for phosphorus, 13.3 mg and 11.1 mg for iron, 4302.8 mg and 3393.3 mg for sodium,2588.0 mg and 2264.9 mg for potassium, and 8.9 mg and 7.3 mg for zinc. The daily intakes of energy, calcium, zinc, vitamin $B_{2}$, and vitamin I were $76.1\%$, $60.1\%$, $73.1\%$, $68.6\%$, and $80.4\%$ of RDAs, respectively. The intakes of energy, calcium, zinc, vitamin $B_{2}$ and I were not meet Korean RDAs. Especially, calcium, zinc, and vitamin $B_{2}$ were less than $75\%$ of RDAs. Blood pressure of the subjects was 128.3/75.5 mmHg for men and 124.1/73.7 mmHg for women. Serum lipids of men and women were 180.2 mg/dL and 184.9 mg/dL for total cholesterol, 160.8 mg/dL and 137.6 mg/dL for triglyceride,41.5 mg/dL and 44.7 mg/dL for HDL-cholesterol,106.6 mg/dL and 112.7 mg/dL for LDL-cholesterol, and 3.5 and 3.3 for atherogenic index. While serum triglyceride and AI of men was significantly higher, HDL-cholesterol was lower than those of women. In the relation among mineral intakes, blood pressure, and serum lipids, we found a significantly negative correlation of intakes of calcium, calcium/phosphorus, calcium density with systolic blood pressure. There were significantly negative correlation between intake of calcium/phosphorus and serum cholesterol, calcium density and serum cholesterol, sodium intake and serum HDL-cholesterol. Based on these results, we concluded that high intakes of calcium, calcium/phosphorus and low sodium intake were associated with favorable blood pressure and serum lipid profiles in adult men and women. (Korean J Nutrition 38(10): 827$\sim$835,2005)