• Journal of Nutrition and Health
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• v.26 no.8
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• pp.974-981
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• 1993

The longitudinal changes on contents of calcium, phosphorous and magnesium of breast milk of 23 Korean lacto-ovo-vegetarians(primiparae=11, multiparae=12) at 0.5, 1, 2 and 3 months postpartum have been studied. The mean ash content of breast milk per 100ml was 0.21g in total lactating women(n=23), and it decreased significantly during lactation(p<0.05). The mean calcium, phosphorous and magnesium contents of breast milk per 100ml were 26.83mg, 14.01mg and 2.72mg, respectively. Body calcium and phosphorous contents decreased significantly during lactation(p<0.05), but magnesium content tended to increase during lactation. There were no significant differences in ash, calcium, phosphorous and magnesium contents between primiparae and multiparae. The ratio of calcium to phosphorus was about 1.95:1 in breast milk and 0.62 : 1 in maternal dietary intake. In calcium and phosphorous, no correlation was found between maternal dietary intake and the concentration in breast milk. This study suggests that the contents of calcium, phosphorous and magnesium in lacto-ovo-vegetarian breast milk are not different from the concentrations of those in non-vegetarian.

• Journal of the Korean Chemical Society
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• v.9 no.1
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• pp.49-54
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• 1965

One of the difficult and time consuming problems in the production of magnesia from sea water is a settling rate of magnesium hydroxide. In this experiments, authors attempted to accelerate its settling rate by addition of various sedimenting agents as C.M.C., Separan and Starch, and sought for optimum calcination temperature for domestic dolomite, as alkali source, mole ratio of dolomite milk to bittern. It is observed through experiments that the small amounts of sedimenting agents, C.M.C., Separan, starch, 20 mg/l, 40 mg/l, 400mg/l, respectively increase the settling rate of magnesium hydroxide by 8 times or more. The following conditions resulted in good yield of magnesium hydroxide from sea water with relatively tolerable calcium oxide contaminated for the magnesium clinker. Calcinating temperature, $1,100{\sim}1,200^{\circ}C$, mole ratio of 10% dolomite milk to magnesium salts in sea water or bittern, 1. 2 : 1.

• Environmental Mutagens and Carcinogens
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• v.25 no.2
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• pp.60-65
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• 2005

The human solute carrier, SLC41Al, is a $Mg^{2}+$ transporter that is regulated by extracellular magnesium. Although intracellular magnesium plays a fundamental role in cellular metabolism, little is known about how $Mg^{2}+$ is taken up and controlled by cells. Magnesium plays a fundamental role in cellular metabolism so that its control within the body is critical. Magnesium homeostasis is principally a balance between intestinal absorption of dietary magnesium and renal excretion of urinary magnesium. The kidney, mainly the distal convoluted tubule, controls magnesium reabsorption. Although renal reabsorption is under the influence of many hormones, selective regulation of magnesium transport is due to intrinsic control involving transcriptional processes and synthesis of transport proteins. Using microarray analysis, identification of the genetic elements involved with this transcriptional control has been begun. SLC41A1(GenBank Accession No. AJ514402), comprises 10 putative transmembrane domains, two of which are highly homologous to the integral membrane part of the prokaryote transports $Mg^{2}+$ and other divalent cations $Sr^2+,\;Zn^2+,\;Cu^2+,\;Fe^2+,\;Co^2+,\;Ba^2+,\;and\;Cd^2+,\;but\;not\;Ca^2+,\;Mn^2+,\;and\;Ni^2+.$ Transport of $Mg^{2}+$ by SLC41Al is rheogenic, voltage dependent, and not coupled to Na or Cl. Expressed SLC41Al transports a range of other divalent cations: $Mg^{2+},\;Sr^{2+},\;Zn^{2+},\;Cu^{2+},\;Fe^{2+},\;Co^{2+},\;Ba^{2+},\;and\;Cd^{2+}$. The divalent cations $Ca^{2+},\;Mn^{2+},\;and\;Ni^{2+}$and the trivalent ion $Gd^{3+}$ did not induce currents nor did they inhibit $Mg^{2+}$ transport. The nonselective cation $La^{3+}$ abolishes $Mg^{2+}$ uptake. Computer analysis of the SLC41Al protein structure reveals that it belongs to MgtE protein family & suggested that the human solute carrier, SLC41Al, might be a eukaryotic $Mg^{2+}$ transporter closely related $(60-70\%)$ protein encoded by SLC41A2 is a $Mg^{2}+$ transporter that might be involved in magnesium homeostasis in epithelial cells also transports a range of other divalent cations: $Ba^2,\;Ni^2,\;CO^2,\;Fe^2,\;or\;Mn^2,\;but\;not\;Ca^2,\;Zn^2,\;or\;Cu^{2+}$ that may have related functional properties.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.4
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• pp.317-322
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• 1994

This study was conducted to increase the seed yield and to find the interaction of several characters of sesame on the reclaimed upland by application of minor nutrient which were boron, magnesium and zinc. A result of testing of boron and magnesium were effective relatively. Application of boron and magnesium were increased the dry stem wt. of upper capsule setting position, Specially dual application of boron and magnesium were remarkable. Dry stem wt. affected on seed increasing of lower and middle capsule setting part. Capsule no. per plant was showed higher degree in dual B+Mg than each application. Capsule no. affected on increasing of dry stem wt. as well as seed yield also. Capsule no. of lower and upper capsule setting part indicated relation with seed yield, 1000 grains weight. This result showed increasing tendency of upper capsule setting part in B+Mg+Zn application. The products of seed yield indicated the increasing of estimate production at the highest 21% in dual Mg+B, 17% of dual B+Zn+Mg secondly, 12% of single boron application thirdly.

• Journal of the Korean Ceramic Society
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• v.31 no.10
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• pp.1147-1158
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• 1994

From Zr(O-nC3H7)4-H2O-C2H5OH-HNO3 starting solutions, MgO-doped stabilized zirconia fibers with varying content of MgO (10~18 mol%) from different MgO sources were fabricated by sol-gel method. The MgO sources used are magnesium nitrate hexahydrate, magnesium acetate tetrahydrate, and magnesium ethylate. The phase transformation studies of a drawn MgO-ZrO2 fiber were carried out using X-ray diffraction, IR spectroscopy, and Raman spectroscopy. The microstructure, tensile strength, and microporosity of fibers were investigated using SEM, tensile strength test, and microporosimeter. Although various MgO sources such as magnesium nitrate, acetate, and ethylate were used, the crystallization behavior of MgO-ZrO2 fibers at different temperatures could be summarized as follows: CubiclongrightarrowMetastable TetragonallongrightarrowMonocliniclongrightarrowCoexistence of Monoclinic and CubiclongrightarrowCubic(trace of monoclinic). At 150$0^{\circ}C$, the phase transformation of MgO-ZrO2 fibers shows the following change depending on the amount of MgO[Mg(NO3)2.6H2O]: At 10 mol%, both monoclinic and cubic phase coexist, at 12 mol%, monoclinic phase decreases rapidly, and then at 14 mol%, only cubic phase remains. When the MgO-ZrO2 fibers containing 12 mol% magnesium nitrate were heated at 80$0^{\circ}C$ for 1hr, average tensile strength of fibers is 4.0 GPa at diameters of 20 to 30 ${\mu}{\textrm}{m}$. As the heat-treatment temperatures increase to 100$0^{\circ}C$ for 1 hr, tensile strength of MgO-ZrO2 fibers decreases rapidly to 0.7 GPa.

• The Journal of the Korea Contents Association
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• v.19 no.11
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• pp.424-433
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• 2019

The purpose of this study was to evaluate the salivary concentration of Potassium and Magnesium cations and their variation before and after sucrose and glucose rinse, and to investigate the relationship between the levels of each compound. Saliva samples were obtained from 40 subjects before and up to 60 min after intake of a 10% sucrose and glucose solution at 1-month intervals. Potassium and Magnesium in human saliva were determined via anion-exchange chromatography with an anion-suppressed conductivity detector using 12 mM sulfuric acid. The concentrations of Potassium and Magnesium before sucrose rinse were 274.3±77.9 mg/ℓ and 4.5±2.5 mg/ℓ, also, the concentrations of Potassium and Magnesium before glucose rinse were 279.2±62.1 mg/ and 4.8±2.0 mg/ℓ, respectively. Potassium and Magnesium concentrations were significantly decreased (p<0.05) after sucrose rinse. The content of potassium and magnesium in saliva before and after rinsing sucrose and glucose is difficult to standardize or classify, as previous research. The reason for the variation between individuals is large, and easily changed by chemical or physiological stimulation. However, this study was experiment for the purpose of accumulating basic data for saliva.

• Journal of Korea Foundry Society
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• v.31 no.5
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• pp.293-301
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• 2011

Representative magnesium alloys applied to the die-casting are AZ91, AM60, etc., and the application of these alloys is restricted to components operating at moderate temperatures, due to grain boundary siding of ${\beta}$-phase($Mg_{17}Al_{12}$) at temperatures above $120^{\circ}C$. Heat-resistant magnesium alloys such as AE42, AE44 have been developed, but that have been too burdensome to produce because of the expensive rare earth materials. Research work for the development of low-priced heat-resistant magnesium alloy is actively in progress and positive results are being reported. This study aims to investigate the effect of Ca additions on mechanical properties of Mg-4Al-2Sn heat resistant magnesium alloys. Mg-4Al-2Sn alloys with Ca (0wt.%, 0.3wt.%, 0.7wt.%, 1wt.%) have been produced through the die-casting process for the development of low-priced heat-resistant magnesium alloy, and high temperature tensile tests are performed using the specimens. The results showed that mechanical properties of Mg-4Al-2Sn-xCa increased with the addition of Ca up to 0.7wt.% Ca and further addition of Ca deteriorated the mechanical properties of the alloys. A significant amount of porosity was observed at the sample with 1wt%. Ca and the longer freezing range of the alloy was believed to cause the formation of porosity.

• Korean Journal of Adult Nursing
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• v.18 no.5
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• pp.809-818
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• 2006

Purpose: The purpose of this study was to evaluate the effect of antioxidant vitamins and magnesium supplementation on fasting blood glucose and lipids in patients with type 2 diabetes. Methods: This study is a unequivalent control group pretest-posttest design. Seventyone subjects with type 2 diabetes who were recruited from home visiting clients of a public health center, completed the trial. The experimental group entered a 12-week treatment period with antioxidant vitamins and magnesium and the control group with no antioxidant vitamins and magnesium. Results: Serum level of fasting blood glucose decreased from $134.7mg/d{\ell}$ to $125.0mg/d{\ell}$ and total-cholesterol decreased from $215.5mg/d{\ell}$ to $198.2mg/d{\ell}$ in the experimental group. No changes in fasting blood glucose and total-cholesterol were demonstrated in the control group. Conclusions: A short-term supplementation with antioxidant vitamins and magnesium can reduce fasting blood glucose and total-cholesterol in patients with type 2 diabetes. The continuous effect of this supplementation and the beneficial effect on the prevention of diabetes complication still needs to be demonstrated.

• Elastomers and Composites
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• v.50 no.3
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• pp.205-209
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• 2015

Magnesium oxide (MgO) reinforced polyamide-66 (PA66) composites were prepared through melt-compounding method in order to determine the possibility of using MgO particle as conductive filler in the polymer-based composite. The effects of MgO filler content on the thermal conductivity and mechanical properties for the PA66/MgO composites were investigated. The results showed that the addition of MgO filler to the PA66 matrix led to a large increase in thermal conductivity of the PA66/MgO composites. Tensile strengths of the PA66/MgO composites were slightly decreased as MgO filler loading increased. However, flexural strength and flexural modulus were improved with increasing filler loading. Notched Izod impact strengths were dramatically lowered by the addition of MgO filler.

• Resources Recycling
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• v.15 no.2 s.70
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• pp.32-36
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• 2006

Magnesium has been used as light and functional material, and its demand is increasing as a material for automobile engine and for mobile phone or notebook PC case. Fused salt electrolysis and thermal reduction are regarded as main methods for the extraction of magnesium, and choice for the method is firstly according to raw material. In this study, magnesium metal is obtained by an electrolysis of magnesium chloride. Two types of fused salt mixtures were used as electrolyte and electrolyzed at 7V with a graphite anode having the same depth, and their results were compared with each other. A mixed salt of $KCl/NaCl/MgCl_2$ was the more effective than $KCl/NaCl/CaCl_2/CaF_2/MgCl_2$ in current efficiency through the experiments at $760^{\circ}C$. Purity of the prepared magnesium metal was above 98%. Some basic data for scale-up of the magnesium electrolysis equipment, which would be necessary for a commercialization, could be obtained.