• 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.

• 아시안잔디학회지
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• 제9권2호
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• pp.109-117
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• 1995

An investigation was performed to reveal the relation of the production and decomposition of the Zoysia japoni ica and Miscanthus sinensis litters on Mt.Kwanak. The decay constant k of litters was as follows; k of Zoysia japonica, k=0.44, k of Miscanthus sicensis, k=0.33 The time required for the decomposition of half of the accumulated organic matter of Zoysia japonice and Miscanthus sinensis was 1.6 and 2.1 years, respectively. The amount of mineral nutrients returned annually to soil is faster in the ZQvsia japonica grassland than in the Miscanthus sinensis grassland on Mt. Kwanak. Key words: Organic rnatter synthesis, Decomposition balance.

• 한국제4기학회지
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• 제17권2호
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• pp.25-32
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• 2003

Mongolia, a land-locked country in Central Asia, is located in the region of the highest degree of seasonal contrast on Earth. This paper presents sedimentologic and geomorphic data used to infer Holocene climate change in North-Central Mongolia. Correlation of data show that the climate was cold and dry before 10500 years BP. The post glacial warming occurred from 10500 to 8700 yr BP. The climate was characterized by becoming warmer and dry from 7300 to 6090 radiocarbon years. Between 6100 and 5500 years ago, conditions were hyper arid. Increased effective moisture balance but still arid conditions prevailed between 5500 and 3900 years ago. Since 3900 years ago, generally more humid conditions prevailed and originated varved sediment accumulation. Between about 2300 to 1300 years ago, greater than present day effective moisture balance. Since 1200 years ago climate was cooler and since 600 years ago becoming warmer.

• Journal of Nutrition and Health
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• 제31권4호
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• pp.716-728
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• 1998

To investigate the effect of dietary Ca levels on metabolic changes of Ca and skeleton in postmenopausal women, 10-month-old ovariectomized female rats were compared with 2 month old rats. The rats were fed either 0.2% or 1.2% Ca diets for 16 weeks. Food intake and weight gain as higher in rats fed high Ca diets and in ovariectomized rats. Apparent Ca absorption as higher, and Ca balance was lower in the low Ca groups. Vertebrae density was higher in old rats or those fed a high Ca diets. The old rats and ovariectomized rats showed decreased bone formation, increased bone resorption and kidney function deterioration resulting in increased urinary Ca excretion. Contradictory to the above observation, old rats and ovariectomized rats still showed higher bone mass and bone ash content. Therefore aging was not fully onging in 10-month-old rats. Bone weights, mineral contents, and mineral/wt ratio were lower in ovariectomized rats. Dietary Ca level did not affect urinary Ca excretion, urinary protein excretion, GFR, serum alkaline phosphatase, or urinary hydroxyporline excretion. This means that dietary Ca level did not influence kidney function or bone turnover. However Ca content and the ash content of femur, 4th vertebra, and scapula were increased in high Ca groups. Therefore, it is considered that decreased bone formation and accelerated bone resorption may account for the increased osteoporotic risk in women in menopause after middle age. However, Ca metabolism can be improved and bone components can be maintained if Ca is supplemented.

• 대한금속재료학회지
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• 제47권5호
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• pp.304-310
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• 2009

Recently, manganese nodule has been focused on alternative resources because of its high grade of noble metallic elements such as Co, Ni, and Cu etc. From the viewpoint of an optimization the operating variables for energy efficiency of smelting reduction process, thermodynamic model for smelting reduction process of Manganese nodule was developed by using energy and material balance concept. This model provided that specific consumption of pure oxygen and coke was strongly depended on post combustion ratio (PCR) and heat transfer efficiency (HTE). The dressing and dehydrating process of low grade manganese can be proposed an essential process to minimize the specific energy consumption with decreasing slag volume. The effect of electricity coal base smelting reduction process was also discussed from the energy optimizing point of view.

• Journal of Nutrition and Health
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• 제41권3호
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• pp.206-215
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• 2008

The purpose of this study was to investigate the effect of manganese (Mn) supplementation on bone status and calcium balance in ovariectomized rats according to the calcium intake levels. Total of 50 Sprague Dawley female rats (6 weeks) were divided into 5 groups and bred for 12 weeks: sham operated control group (SACa), OVX Ca deficiency group (OLCa) with Ca deficiency diet (0.1% Ca modified AIN-93N diet), OVX Ca deficiency & Mn supplement group (OLCaMn), OVX adequate Ca group (OACa; 0.5% Ca AIN-93N diet) and OVX adequate Ca & Mn supplement group (OACaMn). BMD (bone mineral density) of the femur was increased by Mn supplementation in OVX adequate Ca group. However, BMDs of spine, femur and tibia were lowered in OLCa compared to the OLCaMn group. Bone strength of tibia in OLCaMn group was significantly lower than OLCa group. Serum ALP (alkaline phosphatase) and CTx (C-telopeptide of collagen cross-links) levels were significantly higher in ovariectomized rats than those in the sham group, but they were not changed by Mn supplementation. Ca retention rate and Ca absorption rate did not differ among the experimental groups. Urinary Ca excretion was increased by Mn supplementation in Ca deficiency rats. In summary, Mn supplementation resulted in positive effects on bone mineral density ovariectomized rats with which intake adequate Ca. However, Mn supplementation on Ca deficiency ovariectomized rats resulted in decrement of BMO and bone strength by increasing Ca excretion. Therefore, it is encouraged to consider calcium intake levels in supplementation of manganese in order to prevent postmenopausal osteoporosis and to keep bone healthy. (KoreanJNutr2008; 41(3): 206~215)

• 자원환경지질
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• 제41권1호
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• pp.151-163
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• 2008

개방이래로 중국의 빠른 경제성장은 다양한 광물자원의 수요를 초래했다. 동시에 중국의 광물자원 생산은 가파르게 증가하였다. 이러한 중국의 증가된 광물자원 생산 및 수요는 광물 및 금속자원의 전 세계 수급에 큰 영향을 미쳤다. 중국 국토자원부는 알루미늄, 구리, 망간, 우라늄 및 기타 국가 긴급수요에 필요한 광물 등을 10대 전략 광종으로 지정했다. 중국은 국가 경제발전을 위한 자원정책으로서 광물자원의 보호와 합리적 이용, 중국내 광물자원 공급규모의 확대, 자원탐사개발의 대외개방과 협력개발 확대, 광물자원 개발과 환경보호의 균형발전 도모, 광물자원 관리강화를 자원백서에서 제시하고 있다.

• 한국초지조사료학회지
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• 제13권3호
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• pp.184-189
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• 1993

수확시기와 칼륨비료의 시용수준이 각각 다른 오차드그라스(Dactylis glomerata L.)를 대사시험용 케이지 안의 염소(산양)에게 급여하여 목초중 무기질함량이 염소의 무기물질 출납에 어떤 영향을 주는가를 알아보고자 본 실험을 실시하였다. 저칼륨급여구의 오차드그라스 건초중 칼륨과 마그네슘함량은 건물량 기준으로 각각 3.4%와0.26%이었고 중칼륨구의 함량은 4.9%와0.21%이었으며 고 칼륨구의 함량은 5.8%와0.21% 이었다. 고칼륨급여구에서 뇨중칼륨배설량은 저칼륨구보다 유의하게 많았고, 저칼륨구의 분중및 뇨중 마그네슘배설량은 중칼륨구 및 고 칼륨구보다 많았다. 뇨중마그네슘배설량은 혈장의 마그네슘농도 정상관의 경향이 있었으며, 고칼륨급여구의 염소(산양)는 다름 급여구에 비해 음수량과 배뇨량이 많은 경향이었다.

• Asian-Australasian Journal of Animal Sciences
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• 제19권10호
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• pp.1415-1421
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• 2006

Proper nutritional management during the dry period is required to prevent metabolic disorders during the time of parturition and for potential increase milk yield during early lactation, especially under the heat of summer. The effect of prepartum diets on partitioning of nitrogen (N), calcium (Ca), phosphorus (P), magnesium (Mg) and potassium (K) during dry period and early lactation in summer was investigated. Nine cows were assigned to two groups and fed either control (group C: four cows) or high concentrate (group H: five cows) diets to meet 110% of their requirements before parturition. The proportion of concentrate in control diet was 35%, and that in the high concentrate diet was 45%. After parturition, all cows were fed the same diets ad libitum during lactation. Balance trials were conducted at 9, 8 and 7 days before parturition and at 12, 13 and 14 days after parturition. Before parturition, dry matter intake (DMI), DM and NFE digestibility in group C tended to be lower than those in group H. The retention of N (p<0.01) and P (p<0.05) in group C during the dry period was significantly lower than those in group H. The retention of Mg in group C during the dry period tended to be lower than in group H. The concentration of plasma NEFA in group C tended to be higher than in group H during dry period. The prepartum diet did not have an apparent effect on DMI and milk yield at 2 weeks after parturition and N, Ca, P, Mg and K balance after parturition.

• 한국초지조사료학회지
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• 제12권2호
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• pp.98-103
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• 1992

With a purpose of finding out the effects of cattle slurry application on thc nutrient contents of herbages and energy productivity in grassland, a field experiment was conducted with two times and five levels of cattle slurry application. The experimental field was designed in a split-plot with threc replications, and lasted from September, 1986 to October, 1990 at the Livestock Experiment Station in Suweon, The results obtained are summarized as follows: 1. The net energy(NEL, StE and TDN) contents of grasses in the plots with cattle slurry application just after cutting were slightly higher when compared to manuring 15 days after cutting. but DCP content has reverse trend. 2. Average net energy(NEL. StE and TDN) and DCP production of the plot with cattle slurry application 15 days after cutting were insignificantly increased by 26 % than those of manuring just after cutting. The energy and DCP yields in the plot with cattle slurry and with slurry + mineral fertilizer were decreased by 21 -27 % and 8- 11 %, respectively than those of the plot with single dressing of mineral fertilizer. 3. Mineral contents of grasses were not significant difference among the treatments of cattle slurry. but considering nutrient balance of animals, application of cattle slurry of 30-$60m^3$/ha with mineral fertilizer was profitable as compared to the other treatments.