• Journal of Korean Society of Forest Science
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• 제96권2호
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• pp.214-221
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• 2007

The effect of nutrient availability and forest type on the nutrient turnover of fine roots is important in terrestrial nutrient cycling, but it is poorly understood. I measured nutrient turnover of hardwoods and softwoods at three well studied sites in the northeastern US: Sleepers River, VT; Hubbard Brook, NH; Cone Pond, NH. Significant differences in nutrient turnover by fine roots were observed among sites, but not between forest types. The magnitude of differences for each element ranged from 3 times for P and N to 8 times for Ca and Mg between sites. Smaller differences of 0.2 to 0.8 times were observed between forest types. In hardwoods, the Sleepers River 'new' site had $23kg\;ha^{-1}\;yr^{-1}$ Ca, $7kg\;ha^{-1}\;yr^{-1}$ Mg, and $16kg\;ha^{-1}\;yr^{-1}$ K turnover, owing to high root nutrient contents and turnover. Cone Pond had the highest turnover for Mn ($0.8kg\;ha^{-1}\;yr^{-1}$) and Al ($16kg\;ha^{-1}\;yr^{-1}$), owing to high nutrient contents. The Hubbard Brook hardwood site exhibited the lowest turnover of these elements. In softwoods, the variation in turnover of Ca, Mg, and K was lower than in hardwoods. The Hubbard Brook had the highest turnover for P ($1.6kg\;ha^{-1}\;yr^{-1}$), N ($31kg\;ha^{-1}\;yr^{-1}$), Mn ($0.4kg\;ha^{-1}\;yr^{-1}$), Al ($10kg\;ha^{-1}\;yr^{-1}$), Fe ($6.4kg\;ha^{-1}\;yr^{-1}$), Zn ($0.3kg\;ha^{-1}\;yr^{-1}$), Cu ($34g\;ha^{-1}\;yr^{-1}$), and C ($1.1Mg\;ha^{-1}\;yr^{-1}$). Root Ca turnover exponentially increased as soil percentage Ca saturation increased because of greater root nutrient contents and more rapid turnover at the higher Ca sites. These results imply that nutrient inputs by root turnover significantly increase as soil Ca availability improves in temperate forest ecosystems.

• Korean Journal of Environmental Agriculture
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• 제20권1호
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• pp.20-27
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• 2001

Stream water chemistry in the abandoned Boeun Jeil coal mine area was studied for a period of 3 months, including rainy and dry season. The stream waters were a nearly neutral and slightly alkali condition, and $Mg-SO_4$ type with Mg>Ca>Na>K and $SO_4>HCO_3>Cl>NO_3$. Chemical composition of the stream water was quite irregular during the experimental period. Concentrations of Na, K, $HCO_3$, U, Sr, and Cr decreased by $10{\sim}30%$ during rainy season, caused by dilution effects with rain. The concentration of Ca, Mg, $NO_3$, Cd, and Co increased during the rainy season, caused by more easily dissolved from bedrocks or mine drainage with slightly acidic condition than dry season. The stream water was enriched in Mg, Ca, $HCO_3$, $SO_4$, Al, Fe, Zn, Ni, Co, Cr, Cd, Sr and U. Concentrations of Na, Mg, Ca, $SO_4$, $HCO_3$, Fe, Zn, Ni, Sr, and U decreased linearly with distance from the mine adit. These elements were strongly controlled by dilution of unpolluted water influx and/or adsorption on the clay minerals and iron oxyhydroxide precipitates. This mine area exhibited two main weathering processes ; 1) oxidation with acidification derived from Fe sulphides, and 2) pH buffering due to Ca and Mg carbonate dissolution. This weathering processes were followed by adsorption of metals on iron oxyhydroxides and precipitation.

• Korean journal of food and cookery science
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• 제11권5호
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• pp.446-455
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• 1995

The nutritional properties of the Chol-Pyon were investigated with changing the materials (mugwort and pine leaves). In proximate composition, rice powder added mugwort and pine leaves showed the lligher con-tents of crude protein, crude lipid and crude ash than in rice powder. Ihe pH of rice powder, mugwort and pine leaves was 6.4, 6.8 and 3.5, respectively. The rice powder added pine leaves showed the lowest pH value. The content of the free sugar in raw materials for ChOl-PyOn preparation was 0.9% in rice powder, 0.3% in mugwort and 2.7％ in pine leaves. Eighteen kinds of amino acids were determined in raw materials for ChOl-fyOn preparation and their contents were 4.8% in mugwort, 4.2% in rice powder and 2.8% in pine leaves. The major minerals of raw materials for ChOl-PyOn preparation was 0.9％ increased in the order of K> Na > Mg > Ca in rice powder, Mg > K > Ca > Na in mugwort, and K > Ca > Mg > Na in pine leaves. Both of mugwort and pine leaves additives showed the higher contents of 8 kinds of minerals (Ca, Mg, K, Na, Mn, Fe, Cu, Zn) than in rice powder. In relation to changes in the texture of ChOl-PyOn, hardness, fracturability and adhesiveness at 25${\pm}$1$^{\circ}C$ were measured to be highest in white ChOl-PyOn. Cohesiveness was shown to be highest at 15％ in case of mugwort and 2.5％ in case of pine leaves. Elasticity was measured to be highest at 0.99 in case that 7.5% mugwort was added to raw materials for ChOl-PyOn. As a result of estimating the sensory qualities of the ChOl-PyOn prepared to which the additives were added in differing amounts, immediately after its preparation the mugwort additive of 7.5％ showed the superior sensory qualities Chol-PyOn (p < 0,01).

• The Korean Journal of Food And Nutrition
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• 제24권3호
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• pp.434-441
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• 2011

In this study, certain quality characteristics of kimbugak samples prepared with 2 different puffing methods, microwave oven and frying, and containing different levels of sea tangle powder(0, 2, 4, and 6%), were examined according to mineral content, moisture content, color values, photographic images, hardness and sensory evaluations. The mineral contents of Porphyra yezoensis were: K, 2,612.400 mg; Ca, 116.970 mg; Na, 486.099 mg; Mg, 297.800 mg; Fe, 9.636 mg; Mn, 1.614 mg; and Cu, 0.973 mg. And those of the sea tangle powder were: K, 5,115.000 mg; Na, 1,848.931 mg; Ca, 763.030 mg; Mg, 525.700 mg; Fe, 15.125 mg; Zn, 4.639 mg; and Mn, 0.146 mg. Moisture content was not significantly different among the samples of kimbugak puffed by the microwave oven and frying. For the color of the kimbugak made with the microwave oven or frying, L values decreased as the level of sea tangle powder increased. Color a and b values were lowest in the control group. The color values(L, a, and b) of the kimbugak puffed by frying were higher than those made using the microwave oven. The hardness of the kimbugak samples puffed using the microwave oven were not significantly different according to levels of sea tangle powder, and in the kimbugak puffed by frying, the lowest hardness was in the sample with 6% sea tangle. In sensory evaluations, color and crispness were not significantly different among the samples. The flavor scores of the 4% and 6% samples puffed by frying were higher than those of the kimbugak samples puffed using the microwave oven. The overall acceptability of the kimbugak puffed by frying and containing 6% sea tangle powder was the highest. In conclusion, 4 and 6% sea tangle powder would be considered optimum amounts for kimbugak puffed by frying.

• Analytical Science and Technology
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• 제5권4호
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• pp.401-408
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• 1992

The ion-selectrodes based on calcium ferrite were prepared by mixing calcium oxide with ferric oxide on molar ratio of 0.6:1.4, 0.8:1.2, 1.0:1.0, respectively. The specimens were sintered at $1400^{\circ}C$ for 2hrs in $O_2$ and for 20min in $H_2$ atmosphere. The selectrode sintered in hydrogen atmosphere showed better responded potential and wider range of responded concentration than selectrode sintered in oxygen atmosphere. The ion-selectrodes base on calcium ferrite(0.6:1.4 molar ratio.) showed the highest potential to bivalent cations such as $Ca^{2+}$, $Ba^{2+}$, $Mg^{2+}$, $Zn^{2+}$ and halogen anions such as $I^-$, $Br^-$ in the range of $10^{-1}{\sim}10^{-7}M$. It showed good agreement with theoretical nernstian values.

• Journal of Food Hygiene and Safety
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• 제20권2호
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• pp.98-102
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• 2005

As a part of basic investigation for utilizing cultured eel and by-products as a food source, a mineral contents and fatty acid composition of bone and flesh were investigated. Flesh of cultured eel was higher in moisture and crude protein content, and lower in crude ash and lipid content than those of the bone. Mineral of bone were measured 220.72 mg/100 g of Ca, 169.87 mg/100 g of P, 117.05 mg/100 g of Na,92.75 mg/100g of K, 6.18 mg/100g of Cu,5.02 mg/100 g of Zn,2.56 mg/100 g of Fe, and flesh were measured 120.23 mg/100g of CL 150.36 mg/100 g of P, 136.36 mg/100 g of Na, 89.36 mg/100 g of K, 4.02 mg/100 g of Cu, 1.71 mg/100 g of Zn,2.03 mg/100 g of Fe. The major fatty acid in bone and flesh of cultured eel were generally oleic acid $(44.40\%, 43.76\%)$, palmitic acid $(24.19\%,\;21.30\%)$, palmitoleic acid $(8.18\%,\;7.72\%)$, eicosapentaenoic acid $(5.72\%,\;6.65\%)$, myristic acid $(3.96\%,4.34\%)$ in order. The fstty acid composition of total lipid was no significant difference among bone and flesh of cultured eel, However, bone of cultured eel revealed higher content in saturated and monounsaturated fatty acid, while lower in polyunsaturated fatty acid than those of the flesh. It is shown that cultured eel contains various nutrients such as protein, minerals, unsaturated fatty acid, so cultured eel can be regarded as a highly nutritious food.

• Journal of the Korean Society of Food Science and Nutrition
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• 제20권5호
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• pp.479-482
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• 1991

The medical use of Acer mono MAX. and Betula costata T. sap has had the long history in Korea. So the mineral and sugar contents of these sap gathered in Mt. Jiri area at spring were analyzed to investigate the scientific base of folk remedies by using ion liquid chromatography and high performance liquid chromatography. The values of chlorine and sulfate in Acer mono MAX. were 11.5 mg/l and 176.7 mg/l, and in Betula costata T. 26.5 mg/l and 162.4 mg/l, respectively. The values of potassium, sodium, calcium and magnesium in Acer mono MAX. were 67.9 mg/l, 5.6 mg/l, 73.8 mg/l and 4.5 mg/l, and in Betula costata T. were 152.1 mg/l, 9.7 mg/l, 39.2 mg/l and 5.7 mg/l, respectively. The values of copper, zinc and manganese in Acer mono MAX. were 0.057 mg/l, 0.483 mg/l and 5.071 mg/l, and copper, zinc, mangances and iron in Betula costata T. were 0.038 mg/l, 1.584 mg/l, 4.354 mg/l and 2.511 mg/l, respectively. The values of sucrose in Acer mono MAX. were 27.29 mg/l, glucose and fructose in Betula costata T. were 0.97 g/l and 3.05 g/l, respectively.

• Korean journal of food and cookery science
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• 제15권5호
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• pp.545-549
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• 1999

This study was performed to estimate mineral contents of some underground vegetables including potatoes, sweet-potatoes, carrots, radishes, onions, garlics, gingers, burdocks, and lotus roots produced in Korea using ICP-AES (Inductively Coupled Plasma-Atomic Emission Spectrometry). According to the measurement, the amounts of Na, Mg, Al, K, Ca, Mn, Fe, Zn, and P in underground vegetables are variable depending upon harvest time and individual plants. It was noticeable that the carrots showed quite higher amounts of Na compared to other underground vegetables. The amounts of Cd, Ba, Sr and Pb appeared to be below hazard levels. In the near future we expect that this study can be used to calculate the mineral intake from underground vegetables.

• Korean Journal of Community Nutrition
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• 제1권2호
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• pp.215-227
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• 1996

This study was conducted to assess biochemical nutritional status and health status of 53 men and 130 women aged over 65 years and residing in low-income areas in Seoul. Nutritional status and health status were determined by hematological analysis, incidence of disease, and clinical symptoms. Mean serum cholesterol levels were 159.7mg/dl in men and 182.4mg/dl in women and triglyceride levels were 124.6mg/dl in men and 130.6mg/dl in women. The serum lipid levels were higher in women than in men, and 88% of the subjects belonged to normal range and 12% belonged to hyper lipid. The mean hematological indices.; Hb, Hct, RBC, MCH, serum iron belonged to normal ranges. The proportion of anemic state were 16~18% in men and 20~25% in women. Mean serum Ca, Cu and Zn levels were 9.4mg/dl, $84.2\mu\textrm{g}/dl$ and $75.8\mu\textrm{g}/dl$ for male and $9.5\mu\textrm{g}/dl$, $88.3\mu\textrm{g}/dl$ and $75.6\mu\textrm{g}/dl$ for female, respectively. However, proportion of low Ca, Cu and Zn status were 8~20%, 77~84% and 12~34%, respectively. The biochemical indices were not significantly different according to age, BMI, obesity rate. Cholesterol, RBC, MCH and serum iron levels were significantly different between men and women. (Korean J Community Nutrition 1(2) : 215-227, 1996)

• Korean Journal of Food Science and Technology
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• 제34권4호
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• pp.541-545
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• 2002

Stability of Monascus pilosus pigment was investigated under various conditions. The concentration of the pigments stored under air and sub-atmosphere (250 mmHg) for 30 days at room temperature decreased by 77.9% and 48.4%, respectively. The pigment solution was stable under temperature ranges of $20-80^{\circ}C$, pH 4-8, darkness and presence of KCl, NaCl, $CaCl_2$, $MgCl_2$, and $ZnCl_2$. In contrast, the pigment solution was relatively unstable, decreasing in concentration by 6.0 and 11.6% at 100 and $121^{\circ}C$, 15.5 and 13.7% at pH 3 and 9, 22.9 and 66.8% under fluorescence and sun light, respectively, and 20.2% in the presence of $AlCl_3$.