• 한국세라믹학회지
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• 제37권6호
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• pp.564-568
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• 2000

Spinel LiMn2O4 catalyst with submicron and single phase particles was synthesized at 48$0^{\circ}C$ for 12 hr in air by a sol-gel method. The spinel LiMn2O4 was deoxidized by hydrogen at various temperatures. Effects of physiochemical properties of the catalyst reduced by hydrogen were examined with X-ray diffractometer, thermogravimetric analysis and scanning electron microscope. The decomposition rate of carbon dioxide was measrued using the catalyst deosidized at 35$0^{\circ}C$.

• Journal of Magnetics
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• 제10권1호
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• pp.33-35
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• 2005

Perpendicular magnetization curves and crystal textures of $[Pd(0.8 nm)/Co(0.8 nm)]_5/FeMn$ multilayers having an exchange-biased perpendicular magnetic anisotropy as a function of FeMn thickness and annealing temperature were measured. As FeMn thickness increases from 0 to 21 nm, the perpendicular exchange biasing field ($H_{ex}$) obtained the maximum value of 130 Oe at FeMn thickness 12 nm. As the annealing temperature increases to $240^{\circ}C$, the H_ex increased from 115 Oe to 190 Oe and the exchange-biased perpendicular magnetic anisotropy disappeared at $330^{\circ}C$.

• 한국세라믹학회지
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• 제39권12호
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• pp.1128-1132
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• 2002

MFS-FET(Metal-Ferroelectric-Semiconductor Field Effect Transistor) 구조의 비휘발성 기억소자용 $ReMnO_3$(Re:Y, Ho, Er) 박막을 금속 유기 화학 기상 증착법(MOCVD)으로 증착하였다. $ReMnO_3$ 박막을 Si(100) 기판 위에 700${\circ}C$-2시간 증착 시켜 결정화를 위해 대기 중에서 900${\circ}C$-1시간 열처리 시 육방정계(hexagonal) 단일상의 $ReMnO_3$ 박막을 형성하였다. 육방정계 단일상 구조에서 $ReMnO_3$ 박막의 강유전 특성은 c-축 배향성에 의존하였으며, c-축 배향성이 우수한 $YMnO_3$ 박막의 잔류 분극(Pr) 값은 105 nC/$cm^2$로 가장 우수하였다. 또한 누설 전류 밀도(leakage current density) 값은 미세구조의 결정립 크기에 의존하였으며, 결정립 크기가 100∼150 nm인 $YMnO_3$ 박막의 누설 전류 밀도 값은 인가전압 0.5 V에서 $10^{-8}$ A/$cm^2$을 나타내었다.

• Asian-Australasian Journal of Animal Sciences
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• 제19권10호
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• pp.1450-1454
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• 2006

Three hundred and seventy-five steers (approximately 7 mo of age and $239.0{\pm}10.4kg$) were utilized to determine the effects of trace mineral (TM) supplementation and source on performance during the on-farm backgrounding and feedlot receiving phases of beef cattle production. At their respective ranches, steers were stratified by body weight into six groups. Groups were then assigned to one of six pens and pens were randomly assigned to treatments. Treatments consisted of: 1) control (no supplemental Cu, Zn, Mn, and Co), 2) inorganic trace mineral ($CuSO_4$, $ZnSO_4$, $MnSO_4$, and $CoCO_3$), and 3) organic trace mineral (iso-amounts of organic Cu, Zn, Mn, and Co). Mineral treatments were fed in alfalfa pellets formulated to supply 360 mg of Zn, 200 mg of Mn, 125 mg of Cu, and 12.5 mg of Co per head per day from either organic or inorganic trace mineral sources. Control steers received alfalfa pellets with no additional Cu, Zn, Mn, or Co. Steers were allowed free access to harvested alfalfa-grass hay throughout the 30-d on-farm backgrounding phase. On day 30 post-weaning, steers were weighed and transported to the feedlot. Steers were blocked by treatment within ranch, stratified by initial body weight, and randomly assigned to one of 36 pens (9-12 head per pen; 12 pens per treatment). Steers remained on the same on-farm backgrounding trace mineral treatments, however, trace mineral treatments were included in the total mixed growing ration. Steers were fed a corn silage-based growing diet throughout the 28 d feedlot receiving period. There was no effect of TM supplementation on performance of steers during the on-farm backgrounding phase. By the end of the 28-d feedlot receiving phase, ADG was similar between control and trace mineral supplemented steers. Steers supplemented with organic TM had greater (p<0.05) ADG than steers supplemented with inorganic TM by the end of the 28-d feedlot receiving phase. Morbidity and mortality rates were similar across treatments.

• 대한지역사회영양학회지
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• 제17권2호
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• pp.146-155
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• 2012

This study aimed to measure and evaluate the intakes of four antioxidant trace elements, namely, Zn, Cu, Mn, and Se in 19-29y-old female university students in Korea. Diet data were collected by 3-day dietary records in 644 subjects. The mean age, height, weight and body mass index of the subjects were 20.08 years, 161.77 cm, 54.26 kg and $20.82kg/m^2$, respectively. The mean, median and 25th-75th percentile intakes of Zn, Cu, Mn, and Se in the subjects were 12.83 mg (12.40 mg, 9.59 to 15.34), 1.30 mg (1.27 mg, 1.00 to 1.57), 3.19 mg (3.12 mg, 2.45 to 3.86), and $50.90{\mu}g$ ($50.17{\mu}g$, 37.59 to 64.35), respectively. The proportion of subjects whose Mn intake was adequate or less was 62.89%, and the proportions of subjects whose Zn, Cu and Se intakes were at the estimated average requirements or less were 10.09, 4.97, and 39.60%, respectively. The major food group for dietary intakes of Zn, Cu, Mn, and Se was cereal, providing 8.55 mg (66.60%), 0.78 mg (59.93%), 2.09 mg (65.50%), and $16.83{\mu}g$ (32.43%), respectively. Many female university students were deficient in Mn and Se compared with the dietary reference intakes. Therefore, except for cereal, it is required to consume a diet consisted of various food sources for increasing the intakes of antioxidant trace minerals, especially animal food groups.

• 한국결정성장학회지
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• 제12권6호
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• pp.269-269
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• 2002

희박 자성 반도체 ZnMnTe를 장벽층으로 사용한 양질의 ZnTe/ZnMnTe 단일 양자우물 구조를 열벽적층 성장법으로 성장하였다. 고분해능 X-선 회절측정 결과 ZnTe 우물층이 강하게 스트레인을 받고 있음을 알 수 있었다. 광발광 측정으로부터 무거운 양공 엑시톤 (el-hhl)과 가벼운 양공 엑시톤 (el-lhl)의 매우 뾰족한 발광 크들이 나타남을 관측하였다. 또한 우물층의 두께가 증가함에 따라 (el-hhl)과 (el-lhl)의 엑시톤 관련 피크들은 낮은 에너지 쪽으로 이동하였다. 광발광 피크 세기의 온도에 따른 변화는 운반자들의 열적 활성화로 설명할 수 있었다.

• 한국결정성장학회지
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• 제12권6호
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• pp.267-271
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• 2002

희박 자성 반도체 ZnMnTe를 장벽층으로 사용한 양질의 ZnTe/ZnMnTe 단일 양자우물 구조를 열벽적층 성장법으로 성장하였다. 고분해능 X-선 회절측정 결과 ZnTe 우물층이 강하게 스트레인을 받고 있음을 알 수 있었다. 광발광 측정으로부터 무거운 양공 엑시톤 (el-hhl)과 가벼운 양공 엑시톤 (el-lhl)의 매우 뾰족한 발광 크들이 나타남을 관측하였다. 또한 우물층의 두께가 증가함에 따라 (el-hhl)과 (el-lhl)의 엑시톤 관련 피크들은 낮은 에너지 쪽으로 이동하였다. 광발광 피크 세기의 온도에 따른 변화는 운반자들의 열적 활성화로 설명할 수 있었다.

• 한국반도체및디스플레이장비학회:학술대회논문집
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• 한국반도체및디스플레이장비학회 2006년도 춘계학술대회
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• pp.225-231
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• 2006

.고상반응법 (solid state reaction)합성된 ZnS:Mn,Cu,Cl 형광체는 약 $20^{\sim}25{\mu}m$ 의 구형이고, Cubic/hexagonal 구조를 보였다. Electroluminescent device(ELD)는 실크 스크린된 형광층(ZnS:Mn,Cu,Cl)/유전체층 ($BaTiO_3$)으로 구성되었으며, 각층은 $30^{\sim}50{\mu}m,\;50^{\sim}60{\mu}m$ 정도로 도포 하였다. 100 V-400 Hz 의 구동조건에서, ELD 의 백색 발광은 450 nm, 480 nm 픽에서 각각 $Cl_s{\to}Cu^{+}\;_{Zn},\;Cl_s{\to}Cu^{2+}\;_{Zn}$ 전이에 의해 중첩된 청색, 녹색 밴드의 발광과, 580 nm 픽에서 Mn 의 $^{4}T_1{\to}^{6}A_1$ 전이에 의한 황색 밴드의 발광으로 이루어진다. Cu 농도의 증가에 따라 450 nm 의 발광 밴드의 휘도는 감소하며 580 nm 의 발광 밴드의 휘도가 증가하였고 발광 휘도가 향상되었다. 즉, 색온도가 높은 cold white(10000 K)에서 색온도가 낮은 Warm white(3000 K) 로 변한다. 이것은 450 nm 의 발광 밴드가 580 nm 의 발광 밴드에 흡수되는 에너지 전이 (Energy transfer) 현상에 기인한다. ZnS:Mn,Cu,Cl 의 Mn 1.5 wt %, Cu 2.5 wt.% 에서 최적 발광 휘도를 보이며, 100 V-400 Hz 에서 약 $12cd/cm^2$이였다.

• 한국세라믹학회지
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• 제38권12호
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• pp.1174-1179
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• 2001

상온용 NTC 서미스터로는 주로 Mn-Co-Ni 산화물계가 사용된다. 본 연구에서는 Mn-Co-Ni 산화물게 분말을 이용하여 상온에서 가압성형하여 125$0^{\circ}C$에서 3시간 동안 소결한 후, 100$0^{\circ}C$에서 3시간 유지하여 소결체를 제작하였다. 다양한 조성으로 제조된 서미스터의 전기적 특성을 평가한 결과, MCN622(Mn$_3$O$_4$60wt%, 20wt%, NiO 20wt%)는 가장 낮은 비저항과 상대적으로 높은 B 정수를 나타내었고, MCN721(Mn$_3$O$_4$70wt%, Co$_3$O$_4$20wt%, NiO 10 wt%)는 다는 조성들에 비해 현저히 높은 비저항값을 나타내었다. 또한, 각 조성들의 경시변화는 $\pm$2%이내로서 비교적 안정한 특성을 나타냈다.

• 한국전기전자재료학회논문지
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• 제35권3호
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• pp.292-296
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• 2022

(La_0.5Nd_0.2Sr_0.3)MnO₃ specimens were prepared by a solid-state reaction. In all specimens, X-ray diffraction patterns of an orthorhombic structure were shown. The fracture surfaces of (La_0.5Nd_0.2Sr_0.3)MnO₃ specimens showed a transgranular fracture pattern be possibly due to La ions (0.122 nm) as a perovskite A-site dopant substituting for Nd ions (0.115 nm) having a small ionic radius. The full-width at half maximum (FWHM) of the Mn 2p XPS spectra showed a value greater than that [8] of the single valence state, which is believed to be due to the overlapping of Mn²⁺, Mn³⁺, and Mn⁴⁺ ions. The dependence of Mn 2p spectra on the Mn³⁺/Mn⁴⁺ ratio according to sintering time was not observed. Electrical resistivity resulted in the minimum value of 100.7 Ω-cm for the specimen sintered for 9 hours. All specimens show a typical negative temperature coefficient of resistance (NTCR) characteristics. In the 9-hour sintered specimen, TCR, activation energy, and B25/65-value were -1.24%/℃, 0.19 eV, and 2,445 K, respectively.