• Journal of the Korean Crystal Growth and Crystal Technology
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• v.30 no.4
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• pp.143-149
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• 2020

Calcium phosphates recognized as important bio-materials have been successfully synthesized by simple precipitation using waste abalone shells, which are rich mineral sources of calcium. Calcium hydroxide (Ca(OH)₂) originated from abalone shells was used as calcium source (precursor) for the preparation. Synthesis of calcium phosphates was performed by reacting calcium hydroxide with phosphoric acid (H₃PO₄) in aqueous solution. The initial precursor Ca/P ratios were adjusted to 1.50, 1.59 and 1.67, and the effect of the composition and the heat treatment on the synthesized powders and sintered bodies was investigated. The phases of the sintered ceramics prepared at 1150℃ were hydroxyapatite (HAp), β-tricalcium phosphate (β-TCP), and biphasic phosphate (HAp with β-TCP)), which were determined by the initial precursor Ca/P ratios. The results demonstrate the possibility for the synthesis of high value-added calcium phosphates from economical starting materials with low cost and high availability.

• Transactions of the Korean Society of Automotive Engineers
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• v.23 no.2
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• pp.199-207
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• 2015

Solid materials of ammonia sources with SCR have been considered for the application of lean NOx reduction in automobile industry, to overcome complex problems of liquid urea based SCR. These solid materials produce ammonia gas directly with proper heating and can be packaged by compact size, because of high volumetric ammonia density. Among ammonium salts and metal ammine chlorides, calcium ammine chloride was focused on this paper due to low decomposition temperature. In order to make calcium ammine chloride in lab-scale, simple reactor and glove box was designed and built with ammonium gas tank, regulator, and sensors. Basic test conditions of charging ammonia gas to anhydrous calcium chloride are chosen from equilibrium vapor pressure by Van't Hoff plot based on thermodynamic properties of materials. Synthetic method of calcium ammine chloride were studied for different durations, temperatures, and pressures with proper ammonia gas charged, as a respect of ammonia gas adsorption rate(%) from simple weight calculations which were confirmed by IC. Also, lab-made calcium ammine chloride were analyzed by TGA and DSC to clarify decomposition step in the equations of chemical reaction. To understand material characteristics for lab-made calcium ammine chloride, DA, XRD and FT-IR analysis were performed with published data of literature. From analytical results, water content in lab-made calcium ammine chloride can be discovered and new test procedures of water removal were proposed.

• Journal of Nutrition and Health
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• v.33 no.7
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• pp.717-724
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• 2000

A number of epidemiological studies has indicated lifestyles including dietary habits are closely related to the development of certain forms of cancer. These findings have led several investigators to identify the ways in which these factors mdulate the risk of cancer. Seaweeds are rich sources of non-digestible polysaccharides which possibly posses physiological functions. In vitro studies showed several components in seaweeds inhibit tumor cell growth and mutagenicity of known food mutagens. On the other hand non-digestible polysaccharides of different food sources negatively affect mineral nutrition by decreasing mineral absorption. The objectives of this study was to investigate the effect of major seaweed intake on azoxymethane(AOM) - induced DNA damage a known cancer initiation step and on apparent absorption of calcium and iron. To accomplish these objectives twenty five ICR mice were divided into five groups and fed one of the following diets for 10 days : control diet d, diet containing 10% water-soluble fraction of seamustard or seatangle diet containing 10% water-insoluble fraction of seamustard or seatangle. AOM was injected 6 hours before sacrifice and N7-methylated guanines from the colonic DNA were quantified using a gas chromatography -mass spectroscopy. Fecal samples were collected on days 4 and 8. Caclium and iron contents of the diets and feces were analyzed using an atomic absorption spectrophotometry to determine the apparent absorption of these minerals. Results are as follows. AOM-induced guanine methylation of colon was decreased in animals fed diets containing water-soluble fractions of seamustard or seatangle compared to those in animals fed control diet although only the seatnagle fed group showed statistically significant effect. Apparent calcium absorption was significantly reduced in animals fed diets containing water-insoluble fractions of seaweeds. Iron absorption was significantly decreased and negatively balanced in animals fed diets containing water-insoluble fractions of both seaweeds, and water-soluble fraction of seatangle. In conclusion, seamustard and seatangle intakes may effectively prevent colon tumorigenesis by reducing a carcinogen-induced DNA damages, and more mechanistic studies on possible role of seaweeds on carcinogenesis are required. Also, adverse effects of seaweed diets cintaming a large amount of polysaccharides on mineral nutrition should be carefully monitored.

• The Korean Journal of Food And Nutrition
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• v.26 no.3
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• pp.459-469
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• 2013

This study was performed to estimate the salt content and evaluate the nutritional quality of free lunch meals served by welfare facilities for the elderly. We collected food items from 8 welfare facilities in Gyeonggi-do, and calculated the total salt content from the salinity and weight of individual food items. The average salt content from lunch meals was 5.68 g, which was over the recommended daily salt intake by the WHO. The greatest contributor to the salt content among the menu groups was soup and stew (37.5%). Soup, stew, deep-fried foods, and sauces were major sources of salt, while the most salty dishes were sauces, deep-fried food, salt-fermented food, and kimchi. The nutrient content was sufficient, except for calcium in both men and women, which was equal to approximately 1/3 of the dietary recommended intakes (DRIs) for Korean adults of their mean age. In addition, the index of nutritional quality (INQ) and nutrient adequacy ratios (NAR) of most nutrients were satisfactory, except for those of calcium and sodium. The INQs of calcium and sodium were 0.64 and 4.41, respectively, while the mean adequacy ratio of a meal was 0.95. These results suggest that multilateral efforts to lower sodium intake be considered and calcium sources be added, in order to improve the quality of meals served to the elderly at welfare facilities.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.1
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• pp.101-106
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• 2004

This study was conducted to examine the effect of bluefin tuna bone on the bone metabolism of the rats. Weaned 6-week old male rats were fed low-calcium diets for 2 weeks after the adjustment period. Rats were divided into 6 groups and were fed experimental diets for six weeks. Experimental groups were \circled1 Normal calcium: CC (0.5% CaCO$_3$; control) \circled2 TB (bluefin tuna bone powder) \circled3 CT (citrated bluefin tuna bone powder) \circled4 BB (bovine bone powder) \circled5 CL (calcium lactate) \circled6 Low calcium LC (0.15% CaCO$_3$). Low-calcium diet group (LC) showed the lowest calcium retention. There was no differences in calcium excretion in stool and calcium absorption among various calcium sources. Serum calcitonin levels were high in TB, CT and BB group compared to those in CC, CL LC group. Parathyroid hormone and osteocalcin levels showed no differences among experimental groups. Deoxypyridinoline (DPD) levels were significantly higher in LC group than in other groups. Wet weight of the femur were significantly high in TB and CT group, and dry weight of femur showed no differences among normal calcium groups. Bone density of femur in LC group was significantly lower than those of normal calcium feeding group, and TB group showed highest bone density among experimental groups. There was no differences in bone metabolism among various calcium sources. Therefore, it is pointed out that the amount of calcium intake is very important because there was significant differences between normal calcium diet and low calcium diet. According to the results of femur weight, ash, calcium and bone density, it is suggested that bluefin tuna bone have alternative effects to bovine bone powder on the maintenance of bone health.

• Korean Journal of Poultry Science
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• v.27 no.1
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• pp.1-6
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• 2000

An experiment was conducted to determine the nutritional values and variations of food wastes according to seasons and sources. Food wastes were sampled monthly from Feb. to Aug. at gathering sites from home kitchens, school restaurants and Korean food restaurants. chemical analyses revealed that crude fiber and NaCl contents were in the range of 5.41∼10.36 and 3.67∼5.40%, respectively, and the variations were especially high in summer. Ash content was highest in spring. With regard to the sources, the wastes from Korean food restaurants was highest in ash, calcium and phosphorus. On the other hand, crude fiber and fat were highest in the waste from house kitchens and NaCl in those from school restaurants.

• Applied Chemistry for Engineering
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• v.29 no.1
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• pp.43-48
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• 2018

In this study, we performed various extraction condition experiments such as types and concentrations of extractants, amounts of extraction sources, pretreatment processes, to optimize the calcium ion extraction for precipitated calcium carbonate (PCC) production. CaO was used as a calcium extraction source, The extraction amount of calcium ions and the particle size of CaO were determined by ICP and SEM results. As a result, 100% calcium ion was extracted when 2 M hydrochloric acid was used as an extractant, and the optimum amount of the extraction source was 6 g. On the other hand, it was confirmed that the reaction time, reaction temperature, particle milling and heat treatment process had no significant effect on the calcium ion extraction amount.

• Journal of Energy Engineering
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• v.27 no.1
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• pp.51-58
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• 2018

In this paper, we reported that the influence of advanced functional mineral filler calcium carbonate ($CaCO_3$) extracted from oyster shell waste, which are rich mineral sources of $CaCO_3$. Oyster Shells, available in abundance, have no eminent use and are commonly regarded as waste. Their improper disposal causes a significant level of environmental concern and also results in a waste of natural resources. Recycling shell waste could potentially eliminate the disposal problem, and also turn an otherwise useless waste into high value added products. Oyster shell waste calcination process to produce pure lime (CaO) which have good anti-microbial property for waste water treatment and then focuses on its current applications to treat the coffee waste and its effluents for biological treatment and utilization as a fertilizers.

• Journal of Nutrition and Health
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• v.39 no.6
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• pp.539-548
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• 2006

In recent years a concern of excessive intakes of vitamins and minerals from various sources is increasing, since there has been a marked increase in production and consumption of vitamin and mineral supplements and fortified foods. The purpose of this study was to assess the maximum exposure of vitamins and minerals from various sources including diet, fortified foods, and health functional foods among Koreans. As a result, the highest exposure group of most vitamins and minerals from diet was adults (30 - 49 years of age) according to 2001 Korean National Nutrition and Health Survey Report. Maximum dietary intakes of vitamin A, $B_1,\;B_2$, C, nicotinamide, calcium, phosphorus and iron were 0.5 - 7 times of the RDA for Koreans, 7th ed. Maximum intakes of vitamins and minerals from fortified foods by adults (20 - 59 years of age) were 8 - 760% of the Korean RDA. In addition, maximum exposure of vitamins and minerals from vitamin mineral health functional foods by middle aged people was 35 - 140% of the upper limits (UL: DRI for Koreans). As a consequence, maximum combined intakes of vitamin $B_6$, vitamin C, calcium, iron and zinc from the above sources including diet, fortified foods and vitamin mineral health functional foods were greater than the UL. These results would be applied for determining the safe upper limits of vitamin and mineral of health functional foods.

• Mycobiology
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• v.36 no.1
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• pp.34-39
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• 2008

Schizophyllum commune is an edible and medicinal mushroom widely distributed in the world. The optimal growth conditions for the mycelia of 10 strains of the fungus were investigated. The temperature suitable for the mycelial growth and density was obtained at $30{\sim}35^{\circ}C$. Among the tested conditions, the minimum mycelial growth was found at $15^{\circ}C$. In case of pH, the most favorable growth was found at pH 5. The results indicated that this mushroom well adapted to high temperature and low pH for its mycelial growth. Considering growth phenotype of mycelia, Hamada, Hennerberg, PDA and YM were the most suitable and Lilly, Glucose triptone, Glucose peptone and Hoppkins were the most unfavorable among tested media for the mycelial growth of S. commune. Out of tested carbon sources, dextrin and fructose were the most suitable and lactose, mannose and sorbitol were the unsuitable for the fungus. Compact mycelial density was obtained from most of the carbon sources. Among used nitrogen sources, calcium nitrate, potassium nitrate and alanine were the most appropriate and the most incompatible were ammonium phosphate, histidine, urea and arginine for mycelial growth of S. commune on the culture media. Calcium nitrate, histidine and potassium nitrate showed moderately thin or thin, and rest of nitrogen sources showed compact or moderately compact mycelial density.