• 한국항해항만학회지
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• 제31권8호
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• pp.671-674
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• 2007

본 논문에서는 ETC 시스템에서 다중반사로 인한 오신호 또는 시스템간의 간섭을 방지하기 위하여 사용될 전파흡수체를 설계 및 제작하였다. 자성손실 재료인 MnZn-ferrite, 도전손실 재료인 Carbon과 지지재인 CPE를 사용하여 조성비별로 전파흡수체 샘플을 제작하고, 측정된 샘플의 데이터로부터 최적의 조성비가 MnZn-ferrite : Carbon : CPE = 40 : 15 : 45 wt% 임이 확인되었다. 확인된 샘플로부터 재료정수 복소비유전율과 복소비투자율을 계산하여 시뮬레이션 하였으며, 이 결과를 토대로 전파흡수체를 실제 제작하여 전파흡수능을 분석한 결과 시뮬레이션과 실제측정 값이 거의 일치하는 것을 볼 수 있었다. 결과적으로 전파흡수체의 조성비 MnZn-ferrite : Carbon : CPE = 40 : 15 : 45 wt% 로 두께 3.38 mm, 주파수 5.8 GHz대에서 전파흡수능 20 dB 이상의 전파흡수체를 개발하였다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제8권2호
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• pp.87-91
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• 2003

본 연구는 산업시설에서 배출되는 대기오염물질이 인접한 주거지역에 영향을 미칠 것으로 예상되는 시화공업단지 주변의 공단지역, 주거지역 및 녹지지역의 토양을 대상으로 As, Cd, Co, Cr, Cu, Hg, Ni, Pb 및 Zn 함량을 조사하였다. 토양 중 중금속 함량의 범위는 As 0.58~3.81, Cd ND~0.91, Co 0.15~6.33, Cr ND~1.86, Cu 0.14~110.27, Hg ND~l.17, Ni 0.04~10.59, Pb 1.16~86.48 및 Zn 1.83~212.65 mg/kg으로서 전 지역에서 토양환경보전법의 토양오염기준이나 식물독성 유발기준에 비하여 매우 낮은 값을 나타내었다. As 함량은 전 지역에 걸쳐 비슷하였으나, Cd와 Cr 함량은 공단지역이 주거지역이나 녹지지역보다 각각 약 10배 및 5배정도 높았으며, 주거지역과 녹지지역은 비슷한 경향이었다. Co, Cu, Hg, Ni, Pb 및 Zn 함량은 공단지역이 주거지역이나 녹지지역보다 약 2~3배정도 높았으며, 주거지역과 녹지지역은 비슷한 경향이었다.

• 대한화학회지
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• 제30권6호
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• pp.526-531
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• 1986

95% 메탄올 용액에서 코발트(II), 니켈(II), 구리(II)와 아연(II)이온들과 1,15-diaza-3,4:12,13-dibenzo-5,8,11-trioxacycloheptadecane (NenOdien H$_4$, L)리간드와의 안정도 상수를 전위차 적정법으로 25$^{\circ}$C 에서 결정하였다. 그 결과 착물의 형성은 리간드내의 주게원자의 영향을 받으며 안정도 상수의 크기는 Co(II) < Ni(II) < Cu(II) > Zn(II)의 순위이였다. 한편 고체착물의 구조를 분광광도법, 원소분석 및 전기전도도법의 결과로부터 논의하였다. 그 결과 고체상태의 화학조성과 기하구조는 팔면체의 $[CoL_2(OH_2)Cl]Cl{\cdot}2H_2O$, 팔면체의 $[NiL_2(OH_2)Cl]Cl{\cdot}2H_2O$, 사각피라밋형의 [CuLCl]Cl, 그리고 팔면체의 $[ZnLCl_2]{\cdot}\frac{1}{2}H_2O$임을 알 수 있었다.

• Journal of Pharmaceutical Investigation
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• 제18권3호
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• pp.107-111
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• 1988

Zr, Cu, Zn and Fe-pyrithione complexes were prepared in aqueous medium and their antimicrobial activities were evaluated by MIC and cylinder plate methods against Bacillus subtilis, Sarcina lutea, Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella pneumoniae, Trichophyton mentagrophytes, Candida albicans, Asperillus niger and Saccharomyces cerevisiae. Zr-pyrithione possessed most potent activities among the metal complexes against a wide range of microorganisms, especially Gram positive, B. subtilis, S. aureus and fungus, C. albicans. And all of the metal complexes synthesized were more active than pyrithione base. Fe(III)-pyrithione complex has an equal potency to Zn-pyrithione in general but it showed potent activity against B. subtilis microorganism than Zn-pyrithione.

• 한국결정학회지
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• 제11권1호
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• pp.42-45
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• 2000

The complex [Zn(L)Cl](H₂O)(ClO₄) (1) (L=3,14-dimethyl-2,6,13,17-tetraazatricyclo[14,4,O/sup 1.18/,O/sup 7.12/]docosane) has been prepared and characterized by X-ray crystallography. 1 crystallizes in the monoclinic space group P2₁/c, with a=8.883(1), b=19.319(9), c=15.124(2)Å, β=101.65(1)°, V=2542.0(13) ų, Z=4, R₁(wR₂) for 4457 observed reflections of [I>2σ(I)] was 0.0640(0.1557). The coordination geometry around the zinc is a distorted square-pyramid with four nitrogen atoms of the macrocycle occupying the basal sites(Zn-N/sub av/=2.131(2)Å) and a chloride atom at the axial position with the Zn-Cl distance of 2.315(2)Å.

• 한국전기전자재료학회논문지
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• 제13권4호
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• pp.343-348
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• 2000

NCZF ferrites doped with B-Bi-Zn(35-25-40) glass ceramics were prepared to investigate the magnetic properties. The XRD peaks of all of samples were observed only spinel phase. As the additive increased at sintering temperature 750$^{\circ}C$ and 850$^{\circ}C$ for 3 hours, the density and shrinkage of the samples increased until 5.28 g/cm$^3$ and 20% respectively. And other samples showed constant trends having the density about 5.4g/cm$^3$. According to SEM images the growth of grain progressed rapidly at sintering temperature of 850$^{\circ}C$ for 3 hours. Increasing the additive initial permeability and complex permeability decreased. The high values of complex permeability as a function of frequency showed that NCZF doped with 3 wt%, 5wt%, samples at sintered temperature of 850$^{\circ}C$/3h and 900$^{\circ}C$/3h.

• 한국정보통신학회논문지
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• 제3권1호
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• pp.35-42
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• 1999

This paper describes the characteristics of the complex isotropic ferrite-rubber composite for a super wideband electromagnetic absorber in RP-A-PF type, which can be used for an anechoic chamber, wall material to prevent TV ghost, etc. The $Ni_x-A_{0.1}-ZN_{(1-x0.1)}$. $Fe{_2}O_4$ ferrite powder has been fabricated. Using this, then, [$Ni_x-A_{0.1}-ZN_{(1-x0.1)}$. $Fe{_2}O_4$]-Rubber composite for RF-layer in the RF-A-PF type absorber has been fabricated and it's characteristics has been analyzed. As a result, it has been shown that the [$Ni_x-A_{0.1}-ZN_{(1-x0.1)}$. $Fe{_2}O_4$].Rubber composite has excellent electromagnetic wave absorbing properties.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 추계학술대회 논문집
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• pp.89-92
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• 1999

NCZF ferrites doped with B-Bi-Zn(35-25-40) glass ceramics were prepared to investigate the magnetic properties. The XRD peaks of all of samples were observed only spinel phase. As the additive increased at sintering temperature 750$^{\circ}C$ and 850$^{\circ}C$ for 3 hours, the density and shrinkage increased until 5.28g/㎤ and 20%, respectively. According to SEM images, the growth of grain progressed rapidly at sintering temperature 850$^{\circ}C$ for 3 hours. Increasing the additive, initial permeability and complex permeability decreased. The complex permeabilities as a function of frequency showed high values at a12, a16, b11 and b16 sarmples.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1996년도 추계학술대회 논문집
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• pp.303-305
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• 1996

The electrical Properties of ZnO added TiO$_2$were investigated by using the complex impedance measurement and voltage-current source and measurement unit. The electrical conductivity of ZnO added TiO$_2$decrease with increasing the content of ZnO. The frequency-dependent Ac conductivity increase as frequency increase. Also, the trend of capacitances is similar to the AC conductivity. The semicircles of impedance spectrum increase with increasing ZnO contents. The decrease of electrical conductivity seems to be the effect of ZnO acceptor adding.

• 한국세라믹학회지
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• 제32권3호
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• pp.313-320
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• 1995

We investigated the preferred orientation, electrical and magnetic properties of the Mn-Zn ferrite thin films deposited on SiO2/Si(100) by ion beam sputtering. The Cu-added Mn-Zn ferrite thin films had a preferred orientation of (111) with a weak orientation, (311). While the Zn-added one had a strong (111) preferred orientation. The saturation magnetization of the Cu- or Zn-doped Mn-Zn ferrite films increased with increasing substrate temperature (Ts) due to the increase of grain size and the enhancement of crystallinity. For the same reason the coercivity of Cu- or Zn-doped Mn-Zn ferrite films deposited at low Ts increased with increasing Ts, but those of the films deposited at high Ts slightly decreased not only because the defect density of the films decreases but because more grains have multi-domains with increasing Ts. The resistivity of Cu- or Zn-added Mn-Zn ferrite thin fims measured by complex impedance method decreased with increasing Ts due to the ehhancement of crystallinity as well as due to the increase of grain size.