• 한국식품영양과학회지
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• 제27권5호
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• pp.928-934
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• 1998

The purpose of this study was to investigate differences of Ca, Mg and Zn utilization in young and adult rats fed standard diet for 3 weeks. Feed intake and body weight gain in young rats were significantly higher than in adult. There were no significant differences in serum levels of Ca and Zn across age and sex. In liver of young or male groups, Ca and Zn contents were significantly higher than in adult or female. There were no significant differences in tibia contents of Ca and Mg, but Zn content was increased when young or female groups was compared with the other groups. In mineral balances, daily intakes and retentions of Ca, Mg and Zn in young or male groups were significantly higher than those in adult or female. According to this results, it could be suggested that in growth period must be increased dietary intake of Ca, Mg and Zn to compromise the requirement for growth.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2012년도 춘계학술발표회 논문집
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• pp.127-127
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• 2012

비대칭 마그네트론 스퍼터링을 이용하여 다양한 공정조건에서 조성을 변화시키며 Zn-Mg 합금 박막을 합성하였으며, 합성된 박막의 기초특성 분석을 실시하였다. 기존의 마그네트론 스퍼터링 공정으로 낮은 Mg 조성의 Zn-Mg 박막을 합성 할 경우 porous한 박막이 합성 되었다. 본 연구에서는 모든 조성의 Zn-Mg 박막의 치밀화를 위하여 차별화된 박막 합성 기술을 연구하였다. 본 연구에서 개발된 박막 합성 기술을 적용하여 Zn-Mg 박막을 합성 한 결과 3wt.% Mg 타겟을 이용하여도 치밀한 조직의 박막을 합성할 수 있었다. Zn-Mg 박막의 경도는 박막의 Mg 조성이 높을수록 증가하여 최고 403.1Hv를 나타냈다.

• 열처리공학회지
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• 제20권5호
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• pp.243-249
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• 2007

The age hardening behavior and mechanical properties of an extruded Al-Zn-Mg-(Cu)-0.1 wt.%Sc alloy were investigated with the Sc addition and ageing temperature. The results showed that the $Al_3Sc$ compounds were formed by Sc addition and distributed preferentially along the extrusion direction. The age hardening of Al-Zn-Mg-Cu-0.1 wt.%Sc alloy which was treated by T6 process was more significant than that of Al-Zn-Mg-0.1 wt.%Sc alloy. The tensile property of Al-Zn-Mg-Cu+0.1 wt.%Sc alloy was also higher than that of Al-Zn-Mg-0.1 wt.%Sc alloy, which is 691 MPa and 584 MPa in strength and 9% and 11% in elongation, respectively.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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• pp.178-178
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• 2007

II-VI의 넓은 밴드갭 (3.37 eV)을 가지는 ZnO는 solar cells, transparent conductive electrodes, ultraviolet light emitters, and chemical sensors 등에 응용되고 있다. 특히 고효율 ZnO계 발광 소자 구현을 위하여 MgO (7.7eV), CdO (2.0eV) 등의 고용을 통한 밴드갭을 엔지니어링 하며, 단파장 영역의 광원을 확보하기 위하여 MgO 첨가를 통한 밴드갭 에너지를 증가시키는 방향으로의 연구가 활발하다. 그러나 ZnO의 wurtzite 구조와 MgO의 rocksalt 구조의 상이한 결정구조로 인하여 Mg의 고용한계는 4 at. %, 4.1 eV 알려져 있다. 본 실험에서는 p-type Si (100), c-sapphire (0002)과 GaN 기판 위에 MgO (99.999 %)와 ZnO (99.999 %) 두가지 타겟을 사용하여 RF co-스퍼터링법으로 ZnMgO 박막을 증착 하였다. 이때 ZnO 타겟의 power 밀도는 고정 시키고 MgO 타겟의 power 밀도를 변화 시키며 Mg의 함량을 조절하여 그에 따른 광학적 구조적 특성의 변화를 연구 하였다. 성장된 ZnMgO 박막은 MgO 타겟의 power 밀도가 증가할 때 Mg의 함량이 10 at. %까지 증가 하며, 그에 따른 표면의 거칠기 및 입계 크기가 감소하며, 박막의 성장속도 또한 감소함을 SEM과 AFM을 통하여 알 수 있었다. XRD를 동하여 ZnMgO 박막의 (0002) peak의 위치는 $34.50^{\circ}{\sim}34.7^{\circ}$로 오른쪽으로 이동하며, c-축으로 성장하였음을 알 수 있다. PL과 UV룰 동하여, Mg의 함량이 증가 할수록 박막의 밴드갭 에너지는 3.2 eV에서 4.1 eV 로 증가하였다.

• 한국재료학회지
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• 제23권2호
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• pp.98-103
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• 2013

$Mg_{3-x}Zn_xSb_2$ powders with x = 0-1.2 were fabricated by mechanical alloying in a planetary ball mill with a speed of 350 rpm for 24 hrs and then hot pressed under a pressure of 70 MPa at 773 K for 2 hrs. It was found that there were systematic shifts in the X-ray diffraction peaks of $Mg_3Sb_2$ (x = 0) toward a higher angle with increasing Zn for both the powder and the bulk sample and finally the phase of $Mg_{1.86}Zn_{1.14}Sb_2$ was formed at the Zn content of x = 1.2. The $Mg_{3-x}Zn_xSb_2$ compounds had nano-sized grains of 21-30 nm for the powder and 28-66 nm for the hot pressed specimens. The electrical conductivity of hot pressed $Mg_{3-x}Zn_xSb_2$ increased with increasing Zn content and temperature from 33 $Sm^{-1}$ for x = 0 to 13,026 $Sm^{-1}$ for x = 1.2 at 323 K. The samples for all the compositions from x = 0 to x = 1.2 had positive Seebeck coefficients, which decreased with increasing Zn content and temperature, which resulted from the increased charge carrier concentration. Most of the samples had relatively low thermal conductivities comparable to the high performance thermoelectric materials. The dimensionless figure of merit of $Mg_{3-x}Zn_xSb_2$ was directly proportional to the Zn content except for the compound with Zn = 1.2 at high temperature. The $Mg_{3-x}Zn_xSb_2$ compound with Zn = 0.8 had the largest value of ZT, 0.33 at 723 K.

• 한국주조공학회지
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• 제32권3호
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• pp.127-132
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• 2012

Al-Zn-Mg alloys, being high strength aluminum alloys, have attracted attention as a material of automobile parts that require higher mechanical properties and lightness. Automobile parts with complex shapes are manufactured by low-priced casting method, but Al-Zn-Mg alloys are difficult to cast because of its poor hot cracking, feeding, and fluidity. Thus fluidity experiments on Al-Zn-Mg alloys were conducted for the castability evaluation. The effects of Mg and Zn, representative elements of Al-Zn-Mg alloys, on fluidity were observed. Spiral mold was used for fluidity experiments and the lengths of solidified specimens were measured after melting and gravity casting. Correlation between microstructures and fluidity length based on the alloy composition was considered. According to the experimental results, as the amount of Mg and Zn increased, fluidity decreased. Also, it was confirmed that fluidity change by the variation of Mg composition was greater than that of Zn.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2007년도 춘계학술발표회 초록집
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• pp.47-48
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• 2007

본 실험에서는 MgO (99.999%)와 ZnO (99.999%)의 두가지 타겟을 사용한 RF co-스퍼터링법을 이용하여 p-type Si (100) 기판 위에 $Zn_{1-x}Mg_xO$ 박막을 증착 하였다. ZnO 타겟의 RF-power은 고정시키고 MgO 타겟의 RF-power를 조절함으로써 Mg 함량을 조절하였다. EDX분석을 통해 MgO RF-power의 증가에 따라 고용되는 Mg의 함량이 증가함을 알 수 있었다. 또한 MgZnO내 Mg 함량이 높아짐에 따라 c-축 격자상수가 감소하는 것을 XRD분석을 통해 알 수 있었고, MgO기반의 2차상은 형성되지 않았다. PL 측정을 통해 Mg함량이 증가 할수록 UV 영역의 파장의 강도는 감소하고 UV 파장의 위치는 blueshift되는 것을 관찰 할 수 있었다.

• 한국표면공학회지
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• 제47권6호
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• pp.330-334
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• 2014

In this study, the Zn-Mg alloy coatings with various Mg contents were deposited using an unbalanced magnetron sputtering process. Their surface microstructure, chemical composition, phase, and corrosion property were investigated. The microstructure of the Zn-Mg coatings changed from porous microstructure to dense one with increasing Mg contents in the coatings. As Mg contents in coatings increased, intermetallic phases such as $Mg_2Zn_{11}$ and $MgZn_2$ were detected from X-ray diffraction (XRD) results. The corrosion resistance of the Zn-Mg alloy coatings was investigated quantitatively using electrochemical impedance spectroscopy (EIS) measurement with 3.5% NaCl solution. The results of EIS measurement showed that the charge transfer resistance and the phase angle of the Zn-Mg alloy coatings were increased from $162.1{\Omega}{\cdot}cm^2$ to $558.8{\Omega}{\cdot}cm^2$ and from about $40^{\circ}$ to $60^{\circ}$ with increasing Mg contents from 5.1 wt.% to 15.5 wt.% in the coatings. These results demonstrate that the Zn-Mg coatings with increasing Mg contents showed an enhanced corrosion resistance.

• 한국응용과학기술학회지
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• 제9권2호
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• pp.165-174
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• 1992

The standardized activated sludge for the biodegradation test of anion surfactants has been produced from the collected microorganisms in the soil and the wastewaters treatment plant. The activated sludge was kept under control of the pH, dissolved oxygen, microorganisms and inoculated the basal medium flasks with LAS and LAS mixed with heavy metals [Cd(II), Cu(II), Zn(II)]. Based of results, the inhibition effect(%) of heavy metals in LAS biodegradation were 1. All 1% when LAS 30mg/l-Cd(II), Cu(II) and Zn(II) 0.1mg/l, respectively 2. All 1${\sim}$10% when LAS 30mg/l-Cd(II), Cu(II) and Zn(II) 1mg/l, respectively 3. All 10${\sim}$40% when LAS 30mg/l-Cd(II), Cu(II) and Zn(II) 10mg/l, respectively 4. All 30${\sim}$65% when LAS 30mg/l-Cd(II), Cu(II) and Zn(II) 100mg/l, respectively And toxicity order of heavy metals to the microorganisms in LAS biodegradation were Cd>Cu>Zn in low concentration(0.1${\sim}$1mg/l)and Cd>Zn>Cu in high concentration(10${\sim}$100mg/l).

• 한국주조공학회지
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• 제40권2호
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• pp.7-15
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• 2020

The high-temperature stability of Mg-8.0Zn-1.6Y (wt.%) alloys upon the addition of Ca has been investigated by characterizing the ignition temperature, microstructure, tensile and creep properties. The ignition temperature increases with an increase in the Ca content, indicating that an addition of Ca enhances the ignition resistance of the Mg-Zn-Y alloy. The as-cast microstructures of all tested alloys mainly consisted of the dendritic α-Mg matrix and I-phase (Mg₃Zn₆Y) at the grain boundaries. In the Ca-added Mg-8.0Zn-1.6Y alloys, the Ca₂Mg₆Zn₃ phase forms, with this phase fraction increasing with an increase in the Ca contents. However, a high volume fraction of the Ca₂Mg₆Zn₃ phase rather deteriorates the mechanical properties. Therefore, a moderate amount of Ca element in Mg-8.0Zn-1.6Y alloys is effective for improving the tensile and creep properties of the Mg-Zn-Y alloy. The Mg-8.0Zn-1.6Y-0.3Ca alloy exhibits the highest tensile strength and the lowest creep strain among the alloys investigated in the present study. The creep resistance of Mg-Zn-Y-Ca alloys depends on the selection of the secondary solidification phase; i.e., when Ca₂Mg₆Zn₃ forms in an alloy containing a high level of Ca, the creep resistance deteriorates because Ca₂Mg₆Zn₃ is less stable than the I-phase at a high temperature.