• Journal of Nutrition and Health
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• 제22권2호
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• pp.91-101
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• 1989

This study was performed to investigate the effects of different dietary magnesium levels on systolic blood pressure and mineral distribution in normotensive and spontaneously hypertensive rats. In experiment 1, Normotensive rats(NTR ; Sprague Dawley, Female) were given diets containing regular magnesium (0.05% Mg ; rMg), marginal magnesium (0.01% Mg ; mMg) or marginal magnesium with stress(0.01% Mg + stress ; mMg + Str). In experiment 2, spontaneously hypertensive rats (SHR ; Kyoto Wistar, Femal) were fed diets containing regular magnesium(0.05% Mg ; rMg) and high magnesium (0.2% Mg ; hMG). The following were found ; 1) NTR treated with marginal magnesium with stress showed significant increase in systolic blood pressure (SBP). Marginal magnesium diet without stress resulted in nonsignificant increase in SBP. Significant in crease of blood pressure showed in NTR treated with marginal magnesium and stress was associated with decreased magnesium and increased calcium content in femur, reticulocyte and plasma. 2) In experiment 2, magnesium supplementation to SHR showed significant attenuation of their systolic blood pressure with increasing age. The attenuation of SBP showed in SHR was associated with increased magnesium, lowered calcium content in cardiac muscle and reticulocyte and decreased plasma sodium and aldosterone level.

• 한국식품영양과학회지
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• 제26권5호
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• pp.936-942
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• 1997

The present study was carried out to investigate the effects of dietary protein and magnesium levels on calcium and magnesium metabolism in male Sprague-Dawley rats. Forty-eight male rats(average weight, 210g) divided into six diet groups; protein 8% and Mg-free diet, protein 8% and Mg 400mg/kg diet, protein 8% and Mg 900mg/kg diet, protein 20% and Mg-free diet, protein 20% nd Mg 400mg/kg diet, and protein 20% and Mg 800mg/kg diet group. After the rats were fed with experimental diets concentration were examined. Kidney weight was significantly higher in protein 8% and Mg-free group compared with other groups. Serum calcium concentration of protein8% group tended to decrease with the increase of the level of magnesium. Serum magnesium concentration in protein 8% and 20% group was lower in Mg-free group than that in other groups(p<0.05) and it also increased as the dietary magnesium level was increased. Urinary calcium and magnesium concentration in Mg-free group were significantly lower than those of other groups.

• 유기물자원화
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• 제30권1호
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• pp.33-39
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• 2022

혐기성 소화 슬러지 탈리여액을 대상으로 마그네슘 공급원이 인산암모늄마그네슘(MAP) 결정화에 의한 인산염 회수에 어떠한 영향을 미치는지 알아보기 위해 회분식 실험을 실시하였다. 마그네슘 공급원으로 염화마그네슘, 수산화마그네슘 그리고 산화마그네슘을 사용하여 다양한 pH (7.5, 8.0 및 8.5) 조건 및 Mg/P 몰 비율(1.0, 1.5, 2.0 및 2.5)에서 인산염 회수를 실시하였다. 그 결과, 마그네슘 공급원과 관계없이 pH 조건과 Mg/P 몰 비율이 높을수록 인산염 회수율이 증가하였다. pH가 가장 낮은 7.5의 조건에서는 Mg/P 몰 비율이 증가할수록 인산염 회수율이 증가하였는데 산화마그네슘, 수산화마그네슘, 염화마그네슘의 순으로 높았다. 그러나 pH가 가장 높은 8.5의 조건에서는 Mg/P 몰 비율과 관계없이 모든 마그네슘 공급원에서 90% 이상의 높은 인 회수율을 얻을 수 있었다. 따라서 낮은 pH 조건에서도 높은 인산염 회수율을 얻을 수 있었던 수산화마그네슘과 산화마그네슘이 경제적인 측면뿐만 아니라 효율적인 측면에서도 염화마그네슘을 대체할 수 있을 것으로 기대된다.

• 한국식품영양과학회지
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• 제12권3호
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• pp.212-218
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• 1983

토끼에 마그네슘 칼슘이 첨가된 식이를 급여하여 토끼의 liver microsomal protein에 함유된 HMG-CoA reductase의 활성과 혈청 콜레스테롤, 트리글리세리드, 마그네슘 및 칼슘의 양을 측정하여 다음과 같은 결과를 얻었다. 1. 혈청 마그네슘의 경우 대조군이 9.5mg% 인데, 마그네슘 첨가군은 평균 8.27이었고, 칼슘을 첨가하여 사육한 실험군에서 상당히 낮은 값 T-D : 3.5, T-E : 3.0, T-F : 4.0, T-G : 7.3으로 평균 4.45를 보였다. 2. 혈청 칼슘의 경우 대조군이 15.3mg %인데, 마그네슘 첨가 실험군은 평균 14.6이나 칼슘 첨가 실험군에 있어서 평균 14.1로서 큰 차이가 없었다. 3. 혈청 트리글리세리드의 경우 대조군 82.8에 비하여 마그네슘첨가 실험군은 평균 60.3이었으나, 칼슘 첨가 실험군은 평균 69.5로서 다소 높은 값을 보여 주었다. 4. 혈청 콜레스테롤의 경우 대조군이 80mg%인데 반하여, 마그네슘 첨가 실험군은 평균 64.3이었고, 칼슘 첨가 실험군은 평균 56.3으로 상당히 낮은 값을 보여 주었다. 5. microsomal protein의 HMG-CoA reductase의 활성의 경우는 대조군이 0.995nmol/min/mg 인데, 마그네슘 첨가 실험군은 평균 0.948을 보였고 칼슘 첨가 실험군은 평균 0.849를 보여 주었다.

• Asian-Australasian Journal of Animal Sciences
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• 제5권2호
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• pp.225-228
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• 1992

The study was undertaken to determine the effect of various levels of dietary magnesium on the metabolizability of magnesium in laying Tsaiya ducks and Leghorn hens. Twenty-five Tsaiya ducks and 25 Leghorn hens were raised in individual cages. The basal diet was mainly consisted of corn starch and isolated soybean protein. At the beginning of the experiments, birds were fed the basal diet added with 500 mg/kg Mg (1070 mg/kg in total by analysis) for 10 days in order to make the birds adapt to the new diet. Then, they were randomly divided into five treatments with five birds for each treatment and fed the experimental diets containing 690, 1070, 1690, 2150 or 2380 mg/kg Mg for 21 days and during the last five days excreta were collected. The experiment was repeated three times each at the age of 25, 31 and 36 weeks. The metabolizability of magnesium in the diet was determined by the indicator method. The metabolizabilities of magnesium for Tsaiya duck and Leghorn hen were 59.9% and 62.5%, respectively as the diet contained 690 mg/kg magnesium, and were significantly decreased (p<0.05) to 39.7 and 30.7%, respectively when the dietary magnesium content was increased to 2380 mg/kg.

• Journal of Nutrition and Health
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• 제31권6호
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• pp.1031-1038
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• 1998

The present study was carried out to investigate the effects of magnesium supplement levels and periods on calcium, magnesium, and phosphorus metabolism in male Sprague-Dawley rats given low protein and magnesium deficient diets for 2 weeks. Serum calcium content was significantly lower in the magnesium supplement group than in the magnesium-deficient group, but calcium excretion in urine and feces was significantly increased as magnesium level and period was increased. Increasing the dietary magnesium level and periods raised serum content and excretion of magnesium in urine k feces. Urinary excretion of phosphorus in two week group was significantly lower in the magnesium supplement group than in the magnesium-deficient group. fecal phosphorus excretion in supplement group (Mg 800mg/kg diet) was significantly higher than that of other group. (Korean J Nutrition 31(6) : 1031-1038, 1998)

• Journal of Nutrition and Health
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• 제28권5호
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• pp.442-450
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• 1995

This study determined plasma glucose, free fatty acid(ffa), epinephrine, norepinephrine, creatine the phosphokinase(CPK), calcium (Ca), magnesium(Mg) and hydroxyproline, Ca and Mg in the heart muscle. Thirty six male Sprague Dawley rats average weighing 110g divided into two diet group : normal Mg group(0.05% Mg), Marginal Mg group(0.005% Mg). After the rats were on experimental diets for 2 weeks, rats for each group were randomly assigned to stress and no stress group and 30 minutes IMMB stress was administered to stress group every day for two weeks. The following were found : 1) Rats fed normal magnesium diet showed decreased plasma glucose and non signficant change in norepinephrine and CPK with IMMB stress, while magnesium deficient rats showed elevated plasma glucose, norepinephrine and CPK with stress. 2) Myocardial hydroxyproline and plasma epinephrine were not significantly different among groups. 3) In the rats fed adequate magnesium, stress increased plasma magnesium while rats on marginal magnesium diet did not show significant change with stress. 4) Plasma and myocardial calcium were increased in rats fed marginal Mg diet, but did not show any significant difference with stress.

• 한국토양비료학회지
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• 제36권4호
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• pp.218-224
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• 2003

최근 고토비료로 등록된 수산화고토는 황산고토와 비교할 때 용해도가 매우 낮으며 토양반응에 미치는 영향 측면에서도 다른 특성을 가지고 있다. 본 연구에서는 이들 두 가지 고토비료를 표준시비량인 $300kg\;MgO\;ha^{-1}$ 수준으로 처리한 경산통 토양에서 배추 재배하여 그 비효를 비교하였다. 수산화고토는 배추의 엽수와 생체중을 증가시키는 효과를 보였으나, 생육 전반에 미치는 효과에 있어서는 황산고토와 비교할 때 통계적으로 유의성 있는 차이를 보이지는 않았다 ($p{\leq}0.05$). 배추의 마그네슘 함량은 생육초기에는 황산고토 처리구에서 높았으나 수확기에 조사된 결과에서는 수산화고토 처리구에서 높았으며, Ca, P, 및 K 함량은 황산고토에 비하여 수산화고토 처리구에서 높았다. 그러나 비종간의 이들 양분 흡수의 차이는 통계적으로 유의하지 못하였다. 황산고토를 처리한 토양의 pH는 대조구에 비하여 낮아졌으나, 수산화고토 처리구에서는 pH가 높아졌고 유효인산 함량 또한 증가하였다. 침출성 Ca 함량은 수산화고토 처리구에 비하여 황산고토 처리구에서 낮게 나타났다. 토양반응과 양분의 유효도에 미치는 영향의 차이는 비종간의 화학적 특성 차이에 기인하는 것으로 판단된다. 따라서 동일한 수준으로 시용할 때, 수산화고토와 황산고토의 작물에 대한 비효는 대등한 것으로 결론지을 수 있으며, 산성토양이나 용탈이 쉽게 일어날 수 있는 사질 토양에서는 산성비료이며 수용성인 황산고토보다 수산화고토의 시용이 유리할 것으로 판단된다.

• Environmental Engineering Research
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• 제19권1호
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• pp.101-105
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• 2014

Three magnesium compounds, $MgO_2$, MgO, and $Mg(OH)_2$, which are supposed to supply oxygen continuously, were applied onto contaminated bay sediment and its ecology in order to activate the local microbial flora. Those compounds were found to reduce chemical oxygen demand (COD), total nitrogen (T-N), and total phosphorus (T-P). Magnesium oxide, in particular, reduced COD by 30% and T-N and T-P considerably. All compounds also suppressed the release of pollutants in the order $MgO_2$, MgO, and $Mg(OH)_2$. Analysis of microbial flora showed that the microbial group treated by $MgO_2$ and $Mg(OH)_2$ was predictably stable; meanwhile, that treated by MgO increased the number of species, but decreased the total number of microorganisms.

• 소성∙가공
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• 제23권8호
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• pp.495-500
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• 2014

Magnesium alloys are currently expected to be widely used for weight reduction of cars and as high efficient materials in the automotive and electronics industries. Although the specific strength of magnesium is excellent, it cannot be easily formed at room temperature due to its HCP structure. However in order to improve the formability of magnesium, it is necessary to investigate its formability in the warm temperature range. In the current study, the aim was to add to the magnesium property database so that the mass production of a magnesium car body can be accomplished. Warm tensile tests were conducted and the forming limit diagram was determined to confirm formability characteristics of magnesium AZ31B alloy sheet. In addition the bending formability and the magnesium damping capacity were evaluated for AZ31B and compared to SPRC440E which is a sheet steel used for car bodies.