• Journal of Nutrition and Health
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• 제41권2호
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• pp.127-134
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• 2008

The effects of vitamin $D_{3}$ supplementation on bone mineral density and bone mineral content in ovariectmized rats were investigated. Forty female Sprague-Dawley rats (body weight 180 g) were divided into two group, ovariectomy and Sham groups, which were each randomly divided into two subgroups that were fed casein and casein supplemented with vitamin $D_{3}$ diets. Bone mineral density (BMD) and bone mineral content (BMC) were measured using PIXlmus (GE Lunar Co, Wisconsin, USA) in spine and femur on 6 weeks after feeding. Osteocalcin and urinary DPD crosslinks value were measured as markers of bone formation and resorption. The body weight gain and food efficiency ratio (FER) were higher in OVX groups than in Sham groups regardless of diets. Serum Ca concentration and urinary Ca excretion were higher in vitamin $D_{3}$ supplemented group than in casein group in Sham and OVX. Crosslinks values were higher in OVX groups than in Sham groups. Spine BMD and femur BMD of ovariectomy group were significantly lower than Sham groups, however vitamin $D_{3}$ supplemented groups were significantly higher than control groups in Sham and OVX. In conclusion, dietary vitamin $D_{3}$ supplementation on ovariectimized rats were significantly increased bone mineral density and bone mineral content in spine and femur.

• 한국식품위생안전성학회지
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• 제7권4호
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• pp.165-172
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• 1992

Among the nutrients of biological importance, minerals are of particular interest in human nutrition because the range of adequate intake is so narrow. As the results of a series of interaction experiments between dietary fiber sources and minerals, there are many inconsistencies in the experimental data regarding the effect of dietary fibers on mineral bioavailability. the mechanism by which dietary fiber might influence mineral absorption is related to its physicochemical properties. These properties involve the ability of dietary fiber to (1) act as a weak cation exchanger, (2) decrease transit time, (3) dilute mineral concentration by increasing fecal bulk and (4) resist digestion in the large bowel. Regardless of the large number of human and animal studies available, a carful review of these publications dose not provide the answer as to whether the adverse effect of dietary fibers on mineral absorption is the fiber itself or some associated dietary factors( e.g. phytate, oxalate, ascorbate, citrate and protein, mineral-mineral interaction, etc) that are responsible for this action. As a result of the complexity of interaction that may take place between minerals. dietary fiber, and other component of food ; it becomes very difficult to blame fiber alone as a negative factor of mineral nutrition. We absolutely need more research with advanced tools rather than metabolic balance study.

• Journal of Nutrition and Health
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• 제35권4호
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• pp.473-479
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• 2002

본 연구에서는 골다공증의 예방 차원에서 골밀도와 영양소 섭취 상태 및 운동과의 상관성을 조사하기 위하여 대구 지역 성인 여성 74명을 대상으로 간이식이 조사법과 면접 및 설문지를 이용하여 영양소 섭취 량과 운동량 등을 조사하였으며 이중에너지 방사선 골밀도 측정기 (DEXA)를 이용하여 척추 골밀도를 측정한 연구 결과를 요약하면 아래와 같다. 1) 운동군과 비운동군의 각각 에너지 섭취량은 1,921 kcal와 1,733 kcal였고, 평균 일일 칼슘 섭취 량은 각각 652 mg과 635 mg으로 두 군간에 유의적인 차이가 없었다. 2) 운동군과 비운동군은 각각 골밀도가 1.16 g $\pm$0.11/$\textrm{cm}^2$, 1.14 g = 0.14$\textrm{cm}^2$이었고, 골무기질 함량 은 각각 49.6 g $\pm$ 7.8, 47.4 g $\pm$ 9.3으로 두 군간에 유의적 인 차이가 없었다. 3) Alkaline phosphatese (ALP)는 운동군이, 비운동군 보다 유의적으로 낮았다 (p < .05) 비운동군에서는 연령과 ALP가 양의 상관관계가 보였으나 운동군에서는 상관성이 없었다. 4) 칼슘 섭취수준에 따라 낮은 25%군과 높은 25%군을 비교하였을 때 높은 25%군의 골밀도는 낮은 25%군 보다 높은 경향을 보였고 골함량은 유의적으로 높았다. 5) ALP는 칼슘섭취가 낮은 25%군이 칼슘섭취가 높은 25%군보다 유의적으로 높게 나타났다.

• 한국약용작물학회지
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• 제20권1호
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• pp.42-46
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• 2012

Soy isoflavones have been suggested to improve bone loss and lipid profile in postmenopausal women and ovariectomized rats. In present study, we investigated the hypothesis that consumption of soybean, mung bean, cowpea and azuki bean has a beneficial effect on lipid profile which associates with bone mass in ovariectomized rats. Forty two female Sprague-Dawley rats were either sham-operated (Sham) or surgically ovariectomized (OVX). Sham and OVX groups were fed a regular AIN-93M diet, but ovariectomized rats with soybean (OS), mung bean (OM), cowpea (OC) or adzuki bean (OA) were fed AIN-93M diet replacing 35% of corn starch with powdered OS, OM, OC or OA for 10 weeks. Total- and LDL-cholesterol concentrations were significantly lower in Sham and OC groups than other OVX groups. There was significant negative association between total cholesterol concentration and bone mineral density (BMD) of tibia in only OC group. In conclusion, total-cholesterol concentration was significantly and negatively correlated with BMD in rats consumed cowpea, suggesting that the reduced cholesterol concentration may have a beneficial effect on bone mass.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2022년도 봄 학술논문 발표대회
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• pp.166-167
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• 2022

The International Energy Agency(IEA) recommends that intergovernmental agreements reduce CO2 emissions by 2050 to about 50% in 2005 in its report. To realize these demands, it is suggested to actively utilize energy efficiency improvement technology, renewable energy, nuclear power, carbon dioxide capture & storage technology (CCS). In the field of building materials and cement, mineral carbonization technology is widely used. Inorganic by-products applicable to greenhouse gas storage include waste concrete, slag, coal ash, and gypsum. If the Mineral Carbonation Act is used, it is expected that about 12 million tons of greenhouse gases can be immobilized every year. Greenhouse gas immobilization using cement hydrate can be immobilized by injecting carbon dioxide into the hydrated products C-S-H, and Ca(OH)2. In the case of immobilization through concrete carbonization, a carbon dioxide promotion test is used, which is often different from the actual carbon dioxide carbonization reaction. If the external carbon dioxide concentration is abnormally higher than the reality, it is thought that it will be different from the actual reaction. In this study, the carbonation phenomenon according to the concentration and identification of the carbon dioxide reaction mechanism of cement hydrate was to be considered.

• Nuclear Engineering and Technology
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• 제56권7호
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• pp.2835-2841
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• 2024

Real-time analysis of metallic mineral grade and slurry concentration is significant for improving flotation efficiency and product quality. This study proposes an online detection method of ore slurry combining the Prompt Gamma Neutron Activation Analysis (PGNAA) technology and artificial neural network (ANN), which can provide mineral information rapidly and accurately. Firstly, a PGNAA analyzer based on a D-T neutron generator and a BGO detector was used to obtain a gamma-ray spectrum dataset of ore slurry samples, which was used to construct and optimize the ANN model for adaptive analysis. The evaluation metrics calculated by leave-one-out cross-validation indicated that, compared with the weighted library least squares (WLLS) approach, ANN obtained more precise and stable results, with mean absolute percentage errors of 4.66% and 2.80% for Fe grade and slurry concentration, respectively, and the highest average standard deviation of only 0.0119. Meanwhile, the analytical errors of the samples most affected by matrix effects was reduced to 0.61 times and 0.56 times of the WLLS method, respectively.

• Korean Chemical Engineering Research
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• 제55권3호
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• pp.279-286
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• 2017

This review paper evaluates different kinds of synthesis methods for calcite precipitated calcium carbonates by using different materials. The various processing routes of calcite with different compositions are reported and the possible optimum conditions required to synthesize a desired particle sizes of calcite are predicted. This paper mainly focuses on that the calcite morphology and size of the particles by carbonation process using loop reactors. In this regard, we have investigated various parameters such as $CO_2$ flow rate, Ca $(OH)_2$ concentration, temperature, pH effect, reaction time and loop reactor mechanism with orifice diameter. The research results illustrate the formation of well-defined and pure calcite crystals with controlled crystal growth and particle size, without additives or organic solvents. The crystal growth and particle size can be controlled, and smaller sizes are obtained by decreasing the Ca $(OH)_2$ concentration and increasing the $CO_2$ flow rate at lower temperatures with suitable pH. The crystal structure of obtained calcite was characterized by using X-ray diffraction method and the morphology by scanning electron microscope (SEM). The result of x-ray diffraction recognized that the calcite phase of calcium carbonate was the dominating crystalline structure.

• 대한금속재료학회지
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• 제48권1호
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• pp.62-70
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• 2010

Leaching and solvent extraction experiments have been performed to develop a hydrometallurgical process for the recovery of nickel and cobalt from nickel laterite ore with high magnesium content. Most of the nickel and magnesium in the laterite ore dissolved at leaching conditions of $80^{\circ}C$ and 100 g/L sulfuric acid concentration. while half of the cobalt and iron were leached at the same conditions. Solvent extraction experiments were carried out with D2EHPA and saponifed D2EHPA from a synthetic solution containing Ni, Co, and Mg. The extraction percentage of Co, Mg. and Ni by D2EHPA was very low in a pH range of 4.4 to 7.3. while the extraction percentage sharply increased by using saponified D2EHPA. The stripping percentage of the metals from the saponified D2EHPA increased with sulfuric acid concentration and reached 99.9% at 1 M $H_2SO_4$ solution.

• 기술사
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• 제32권6호
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• pp.60-67
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• 1999

299 chemical analyses are used to study the characteristics of mineral and thermal waters in South Korea. Even though the concentration of chemical components in thermal waters are generally very low, mineral waters having components more than 1,000 ppm of dissolved total solid(TDS) are reached up to 19% total analyses data, In Germany, Japan or some other countries, mineral and thermal waters are detined not only by water temperature, but also by chemical components. The principle of Law in Japan in also almost same with the German regulations. However, the Law for thermal spring In Korea permit thermal water to be qualifiled only by water temperature. For including chemical characters into the regulations or Law of thermal spring, the limit values of TDS and other 9 micro components related to mineral and thermal waters was selected through this study.

• 기술사
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• 제33권1호
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• pp.75-82
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• 2000

299 chemical analyses are used to study the characteristics of mineral and thermal waters in South Korea. Even though the concentration of chemical components in thermal waters are generally very low, mineral waters having components more than 1,000 ppm of dissolved total solid(TDS) are reached up to 1975 of total analyses data, In Germany, Japan or some other countries, mineral and thermal waters are defined not only by water temperature, but also by chemical components. The principle of Law in Japan is also almost same with the German regulations. However, the Law for thermal spring In Korea permit thermal water to be qualifiled only by water temperature. For including chemical characters into the regulations or Law of thermal spring, the limit values of TDS and other 9 micro components related to mineral and thermal waters was selected through this study.