• Journal of Korea Foundry Society
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• v.34 no.3
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• pp.100-106
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• 2014

In recent years, Mg and its alloys have attracted a great deal of attention due to their low density, relatively excellent castability, and straightforward recyclability. Mg alloys have been widely applied to various industrial fields, and are representatively used in automotive and electronic parts. According to previous researches, the electrical conductivity of Mg alloys greatly decreases with increasing Al content. However, with the addition of Zn and/or Cu, the electrical conductivity of Mg alloys is maintained or slightly increased, and improved mechanical properties are obtained as well. On this basis, Mg-Zn-Cu alloys have been investigated in the present study with a focus on the effect of adding Zn and Cu on the electrical conductivity. The Zn and Cu contents ranged from 4 to 6wt.% and 0 to 1.5wt.%, respectively. Ternary Mg-Zn-Cu alloys have been prepared by gravity casting in a steel mold. In the as-casting condition, the electrical conductivity of Mg-Zn-Cu alloys showed a linear increasing trend with decreasing Zn and increasing Cu contents. Furthermore, impact values of Zn = -1.5 and Cu = 2.5 were determined for these alloys by electrical conductivity tests.

• Journal of Environmental Health Sciences
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• v.10 no.2
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• pp.79-87
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• 1984

The purpose of the study is to determine the effects of Zn in lead poisoning rats by way of examining interaction mechanism of Pb and Zn. The fifty-five rats were Pb divided into four groups such as Zn group, group, Pb and Zn group, and control group. The rats of Zn group and of Zn and Pb group were subdivided into four groups by dose of Zn respectively 250mg/l, 500mg/l, 1, 000mg/l and 2, 000 mg/l. The rats having been fed the above mentioned chemicals, were weighed every five days for fifty-five days, and the subjects were slaughtered for measuring $\delta$-ALAD activities in blood and the accumulation amount of the chemicals in livers and kidneys. The results of the study are summarized as following 1. As for body weight gains, those of the control group rats were the highest, and those of Pb group the lowest. 2. $\delta$-ALAD activities of Pb group showed the tendency of decrease in comparison with those of control group. In Zn group, the subgroups of 250mg/l and 500mg/l showed higher activities than control group, whereas the subgroups of 1, 000mg/l and 2.000mg/l showed lower. 3. Hb value of Pb group was lower than that of control group. In Zn group, Hb value of the groups of 250mg/l and 500mg/l was a little higher than that of control group, while that of the groups of 1, 000mg/l and 2, 000mg/l was lower. 4. The amount of Pb and Zn accumulated in liver was much higher than in kidney. The amount of Pb accumulated in organs of Zn and Pb group decreased gradually in contrast to high concentration of Zn.

• Transactions of the Korean Society of Automotive Engineers
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• v.14 no.5
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• pp.73-78
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• 2006

In this paper, creep tests of Mg-Zn-Mn and Mg-Zn-Mn-Ca alloys, which were casted by mold with Mg-3%Zn-1%Mn and Mg-3%Zn-1%Mn-0.2%Ca, were done under the temperature range of 473-573K and the stress range of 23.42-78.00Mpa. The activation energies and the stress exponents were measured to investigate the creep plastic deformation of those alloys, and the rupture lifes of Mg-Zn-Mn alloy were also measured to investigate the fracture behavior. From the results, the activation energy of Mg-Zn-Mn and Mg-Zn-Mn-Ca alloys under the temperature range of 473-493K were measured as 149.87, 145.98KJ/mol, respectively, and the stress exponent were measured as 5.13, 6.06 respectively. Also the activation energies Mg-Zn-Mn and Mg-Zn-Mn-Ca alloys under the temperature range of 553-573K were obtained as 134.41, 129.22KJ/mol, respectively, and tress exponent were obtained as 3.48, 4.63, respectively. Finally stress dependence of rupture life and the activation energy of rupture life of Mg-Zn-Mn under the temperature range of 473-493K was measured as 8.05, 170.0(KJ/mol), respectively, which were a little higher than the results of steady state creep.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.7
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• pp.1006-1012
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• 2017

Objective: This study was conducted to investigate effects of zinc (Zn) bearing palygorskite (ZnPal) supplementation on growth performance, hepatic mineral content, and antioxidant status of broilers at early age. Methods: A total of 240 1-day-old Arbor Acres broiler chicks were allocated into 5 treatments with 6 replicates of 8 chicks each. Birds in 5 treatments were fed a basal diet supplemented with 0 (Control group; Analyzed Zn content: 81 mg/kg), 20, 40, 60, and 80 mg/kg Zn as ZnPal for 21 days, respectively. Blood, liver and intestinal mucosa were collected at 21 days of age. Results: Treatments did not affect growth performance of broilers during the 21-day study (p>0.05). The contents of hepatic Zn and magnesium (Mg) were linearly increased (p<0.001) by ZnPal supplementation. ZnPal inclusion linearly (p = 0.007) reduced malondialdehyde (MDA) concentration in serum. The activity of total superoxide dismutase (T-SOD) in liver increased linearly (p = 0.001) with concentration of ZnPal in diet. ZnPal inclusion linearly (p = 0.036) and quadratically (p = 0.005) increased T-SOD activity, and linearly (p = 0.012) increased copper/zinc superoxide dismutase (Cu/Zn SOD) activity in jejunal mucosa. The maximum responses of hepatic and jejunal antioxidant enzymes activities (T-SOD and Cu/Zn SOD) were found when supplementing the basal diet with 60 mg/kg Zn as ZnPal. Furthermore, ZnPal supplementation quadratically (p = 0.001) increased Cu/Zn SOD activity in ileal mucosa, and its maximum activity was observed in the diet supplemented with 20 mg/kg Zn as ZnPal. Conclusion: ZnPal supplementation did not alter growth performance of broilers. Dietary ZnPal inclusion could increase concentrations of hepatic trace minerals (Zn and Mg) and inhibit lipid peroxidation by reducing serum MDA accumulation, with the optimal dosage of Zn from ZnPal being 80 mg/kg diet (analyzed Zn content in the diet: 165 mg/kg), and 60 mg/kg Zn as ZnPal (analyzed Zn content in the diet: 148 mg/kg) was the optimum dosage for broilers to achieve maximum antioxidant enzyme activities.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2013.05a
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• pp.86-86
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• 2013

우수한 내식성을 나타내는 Zn-Mg 합금을 강판의 표면처리에 적용하기 위하여 비대칭 마그네트론 스퍼터링을 이용하여 Zn-Mg 박막을 합성하였다. Zn-Mg 박막의 미세조직은 박막 내에 Mg 함량이 증가 할수록 치밀해지며, 합성 중의 온도가 높아지면 박막은 치밀도가 낮아진다. 이렇게 변화하는 Zn-Mg 박막의 미세조직은 박막의 밀착성 및 내식성에 큰 영향을 미치며 미세조직이 치밀할수록 Zn-Mg 박막의 내식성은 증가하나 밀착성은 감소하는 경향성을 나타냈다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.392-393
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• 2007

PDP용 녹색 $Zn_2SiO_4$:Mn 형광체의 발광특성과 결정성을 향상시키기 위해 co-dopant로 Mg를 첨가한 $(Zn_{1-x}Mg_x)_2SiO_4$:Mn 형광체를 합성하였다. 합성된 형광체의 발광특성을 PL로 조사한 결과, $Zn_2SiO_4$:Mn 형광체는 Mg의 농도에 관계없이 530nm에서 녹색 발광을 하였고, Mg의 농도가 0.5 mol%일 때 가장 높은 발광세기가 나타났다. 이것은 Zn과 이온반경이 비슷한 Mg가 치환되어 모체에서의 Mn으로의 에너지 전이가 증가하여 발광세기가 증가한 것으로 생각된다.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.899-901
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• 2009

The magnesium fluoride ($MgF_2$) has very higher optical transmission than oxide or nitride material applied for gas barrier, so we manufactured Mg-Zn-F films with Mg-Zn-F target mixed in the various ratio of $MgF_2$ to Zn and characterized films' properties. Zn is used to increase packing density of barrier film. Thickness and optical transmission of Mg-Zn-F are 200 nm and over 90 %, respectively. The result of water vapor transmission rate at 38, RH 90 ~ 100% of the Mg-Zn-F film deposited with 4 : 6 ($MgF_2$ : Zn) ratio target reached below $1{\times}10^{-3}g$/($m^2{\cdot}day$), measuring limit of instrument.

• Journal of Korea Foundry Society
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• v.26 no.2
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• pp.77-84
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• 2006

The effect of alloy composition on the glass forming ability (GFA) of the Ca-rich Ca-Mg-Zn alloys has been investigated in $Ca_{65}Mg_{5+x}Zn_{30-x}$ and $Ca_{55+x}Mg_{15}Zn_{30-x}$ (x=0, 5, 10, 15, 20) alloys. In a wide composition range of 15-25% Zn and 10-20% Mg bulk metallic glass (BMG) samples with the diameter larger than 6 mm are fabricated by conventional copper mold casting method in air atmosphere. Among the alloys investigated, the $Ca_{65}Mg_{15}Zn_{20}$ alloy exhibits the highest GFA enabling to form BMG sample with the diameter of at least 15 mm. The crystalline phase formed during solidification of $Ca_{65}Mg_{15}Zn_{20}$ ($D_{max}=15\;mm$) could be identified as a mixture of $Ca_3Zn$ and $CaMg_2$ cause by the redistribution of the constituent elements on long-range scale. The compressive fracture strength and fracture elongation of the $Ca_{65}Mg_{15}Zn_{20}$ BMG are 602 MPa and 2.08% respectively. The ${\sigma}$ parameter which has been recently proposed for evaluating GFA exhibits better correlation with GFA of Ca-Mg-Zn alloys than other parameters suggested so far such as ${\Delta}T_x$, $T_{rg}$, K, ${\gamma}$, and ${\Delta}T^*$ parameters.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.26 no.8
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• pp.602-607
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• 2013

Concern for the TOS (Transparent Oxide Semiconductor) is increasing with the recent increase in interest for flexible device. Especially MgZnO has attracted a lot of attention. $Mg_xZn_{1-x}O$, which ZnO-based wideband-gap alloys is tuneable the band-gap ranges from 3.36 eV to 7.8 eV. In particular, the flexible substrate, the crystal structure of the amorphous as well as the surface morphology is not good. So research of MgZnO thin films growth on flexible substrate is essential. Therefore, in this study, we studied on the effects of the oxygen partial pressure on the structural and crystalline of $Mg_{0.1}Zn_{0.9}O$ thin films. MgZnO thin films were deposited on PES substrate by using pulsed laser deposition. We used XRD and AFM in order to observe the structural characteristics of MgZnO thin films. UV-visible spectrophotometer was used to get the band gap and transmittance. Crystallization was done at a low oxygen partial pressure. The crystallinity of MgZnO thin films with increasing temperature was improved, Grain size and RMS of the films were increased. MgZnO thin films showed high transmittance over 80% in the visible region.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.50 no.9
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• pp.434-437
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• 2001

ZnSe, ZnSe:Ho/sup 3+/, Mg/sub x/Zn/sub 1-x/Se and Mg/sub x/Zn/sub 1-x/Se:Ho/sup 3+/ crystals were grown by the chemical transport reaction method. The crystal structures and optical energy band gaps of the single crystals were investigated. Their photoluminescence(PL) spectra were measured at 10 [K]. Sharp emission peaks in the blue-green wavelength range and broad emission peaks in the yellow-red wavelength range were observed. The single crystals doped with 1.0 [mol%] of holmium did not show the sharp emission peaks because of defects which were thought to be originated to the holmium dopant.