• Asian-Australasian Journal of Animal Sciences
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• 제14권11호
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• pp.1523-1526
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• 2001

To study the secretion of trace elements during early lactation, twelve lactating Murrah buffaloes were selected from the herd of the institute. The buffaloes were divided into two groups of six each. Buffaloes of group I were not injected and served as control. Buffaloes of group II received oxytocin injection (2.5 I.U.) intramuscularly for a period of five days for let down of milk. Milk samples were collected from both groups of buffaloes five days before, during and after the administration of oxytocin. Aliquots of milk samples from each buffalo were composited in proportion to their milk yield and used for analysis of trace elements in milk. In both the groups of buffaloes Cu, Mg, Fe, Zn and Mn contents did not vary significantly between animals. However, Ca levels varied significantly (p<0.01) between animals. Administration of oxytocin influenced (p<0.01) Cu, Mg, Zn, Fe and Mn secretion in milk. However, Ca secretion was not affected by oxytocin administration. Secretion of these elements also varied significantly during different days of the study. Zinc content of milk in the control group also varied significantly (p<0.01) during different days and periods of study indicating thereby no effect of oxytocin. The study indicated that administration of oxytocin increases Cu and Mn content and decreases Mg, Fe and Zn content without altering the Ca concentration of milk.

• 한국환경과학회지
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• 제14권6호
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• pp.605-611
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• 2005

The aim of this study was to analyze the local distribution of the heavy metal concentration in Daegu and Ulsan which were divided into the residual areas, the traffic dense areas and the industrial areas. The Inductively Coupled Plasma(ICP) was used to analyze heavy metals, such as As, Cr, Hg, Zn, Cd, Pb, Cu and minor metals, such as Fe, Si, Mg, Ca, AI, Na, K. The results of this analysis showed that the content of heavy metals which was classified by districts in Daegu and Ulsan was the highest in the industrial areas followed by the traffic dense areas and the residual areas. Compared to the level of heavy metals of national and local soil survey network in 2003, contamination of heavy metals in Daegu was lower than national average. However, the content of Cd, As, Zn in Ulsan was respectively 13.38 times, 472 times and 2.65 times higher than national average contamination. In addition, compared to the soil pollution level of the environmental protection law, contamination of all areas in Daegu was lower. But the content of As at the industrial areas in Ulsan was 10.71 times higher than standard of soil pollution and 4.28 times higher than standard of measures against soil contamination.

• 한국건축시공학회지
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• 제14권6호
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• pp.505-513
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• 2014

본 연구에서는 전기화학적인 시험 및 CASS Test(염수분무시험)을 실시하여 중방식도장 시험체와 용융아연도금 시험체, Zn-Al 시험체와의 비교를 통해 Zn-Sn 금속용사의 방식 성능을 평가하였다. 시험 결과, 전기화학 시험을 통하여 Zn-Sn / Zn-Al 상온금속용사 시스템 공법의 방식원리는 방식전위에 의하여 확보되는 것을 확인하였으며 강구조물의 방식 공법으로서 상온금속용사 공법은 용융아연도금 공법과 중방식 도장공법과 비교하여 매우 우수한 방식성능을 가지고 있는 것이 CASS 시험을 통하여 검증되었다. 특히 Zn-Sn 금속용사와 Zn-Al 금속용사를 비교해본 결과 그 방식성이 현저하게 차이가 있지는 않았으나 Zn-Sn(65:35) 비율의 시험체가 가장 우수하였다. 또한 중방식 도장은 손상된 부분에서 현저하게 녹이 발생하고 도막이 박리되지만, Zn-Sn / Zn-Al 상온금속용사 시스템 공법은 갈바닉 희생방식에 의하여 매우 높은 부식 방지 특성을 가지고 있음을 확인 하였다.

• 한국재료학회지
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• 제19권3호
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• pp.125-131
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• 2009

In this report, the structural and optical properties of sol-gel derived $Mg_xZn_{1-x}O$ thin films upon changes in the composition and annealing temperature were investigated. The $Mg^{2+}$ content and the annealing temperature were varied in the range of $0{\leq}x{\leq}0.35$ and $400^{\circ}C{\leq}T{\leq}600^{\circ}C$, respectively. The films exhibited a hexagonal wurtzite structure of a polycrystalline nature. The optical transmittance exceeded 85% and the optical band gap of the film was tuned as high as 3.84 eV at a value of x = 0.35 (annealed at $400^{\circ}C$), which was evidently the maximum $Mg^{2+}$ content for the single-phase polycrystalline $Mg_xZn_{1-x}O$ thin films prepared in this experiment. The optical band gap and photoluminescence emission were tailored to the higher energy side while maintaining crystallinity without a significant change of the lattice constant.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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• pp.367-368
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• 2005

The microstructure and electrical properties of $Pr_6O_{11}$-based ZnO varistors consisting of Zn-Pr-Co-Cr-Tb oxides were investigated with $Tb_4O_7$ content in the range of 0.25~1.0 mol%. The varistor ceramics exhibited very high densification in the range of 5.74~5.83g/$cm^3$ with increasing $Tb_4O_7$ content. Furthermore, the incorporation of $Tb_4O_7$ in varistor ceramics $Tb_4O_7$greatly increased All of the characteristic parameters. As a result, It was found that $Tb_4O_7$-added varistors are good for high voltage field.

• Membrane and Water Treatment
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• 제6권4호
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• pp.309-321
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• 2015

We report in this study the synthesis of mixed matrix reverse osmosis membranes by interfacial polymerization (IP) of thin film nanocomposite (TFNC) on porous polysulfone supports (PS). This paper investigates the synthesis of ZnO nanoparticles (NPs) using the sol-gel processing technique and evaluates the performance of mixed matrix membranes reached by these aerogel NPs. Aqueous m-phenyl diamine (MPD) and organic trimesoyl chloride (TMC)-NPs mixture solutions were used in the IP process. The reaction of MPD and TMC at the interface of PS substrates resulted in the formation of the thin film composite (TFC). NPs of ZnO with a size of about 25 nm were used for the fabrication of the TFNC membranes. These membranes were characterized and evaluated in comparison with neat TFC ones. Their performances were evaluated based on the water permeability and salt rejection. Experimental results indicated that the NPs improved membrane performance under optimal concentration of NPs. By changing the content of the filler, better hydrophilicity was obtained; the contact angle was decreased from $74^{\circ}$ to $32^{\circ}$. Also, the permeate water flux was increased from 26 to 49 L/m2.h when the content of NPs is 0.1 (wt.%) with the maintaining of lower salt passage of 1%.

• 한국토양비료학회지
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• 제28권2호
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• pp.130-134
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• 1995

무연탄회(無煙炭灰)와 유연탄회(有煙炭灰)를 식양토(埴壤土)에서는 12톤/10a씩 1년 및 3년간(年間) 처리(處理)하고, 사양토(砂壤土)에서는 2년간(年間) 처리(處理)된 토양내(土壤內)의 토심(土深) 30cm, 60cm, 100cm에서의 침투수중(浸透水中) 중금속(重金屬) 함량(含量)을 조사(調査)한 결과(結果)는 다음과 같다. 1. 식양토(埴壤土) 논에서 무연탄회(無煙炭灰) 처리(處理)로 Zn는 무처리(無處理)보다 증가(增加)되었으며 토심(土深)이 깊을수록 증가(增加)되는 경향이나 유의성(有意性)은 없었다. 2. 식양질(埴壤質) 논에서 석탄회(石炭灰)를 3년간(年間) 연용(連用)한 결과(結果), 석탄회(石炭灰) 처리(處理)로 Pb와 Zn는 석탄회(石炭灰) 처리(處理)로 무처리구(無處理區) 보다 다소 증가(增加)되었고 토심별(土深別)로는 Pb만이 100cm 토심(土深)에서 증가(增加)되었으나, 기타 성분(成分)은 석탄회처리구(石炭灰處理區)가 무처리구(無處理區) 보다 감소(減少)되었다. 3. 사양질(砂壤質) 논에서 석탄회(石炭灰)를 2년간(年間) 처리(處理)로 무연탄회(無煙炭灰) 처리(處理)에서는 Cd, Ni, Mn은 유의성(有意性)있게 증가(增加)되었고 심토(深土)에서도 증가(增加)되었으나 기타 성분은 유사하거나 감소되었다.

• 한국균학회지
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• 제21권4호
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• pp.273-278
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• 1993

한국에서 야생(野生)하는 6종 식용(食用)버석에 함유된 미량 금속원소의 함량순서는 다음과 같다. 뽕나무버섯은 K가 778.2 ppm으로 가장 많았고 그 다음이 Fe, Na, Zn, Mn, Cu 순이고 Ca은 검출되지 않았으며 뽕나무버섯부치는 K가 (972.9 ppm), Zn, Mn, Fe, Na, CU, Ca 순으로 K함량이 가장 많았다. 자주방망이버섯은 K(699.8 ppin), Zn, Fe, Na, Cu, Mn 순으로 K가 가장 많이 함유되어 있었고 Ca은 검출되지 않았으며 자주방망이버섯아재비는 K(945.2 ppm), Zn, Fe, Na, Cu, Mn, Ca 순으로 K이 가장많이 검출되었다. 벚꽃버섯은 K(878.6 ppm), Zn, Fe, Na, Cu, Ca, Mn 순으로 K가 최고치였고 붉은산무명버섯은 Zn(6637.3 ppm), Fe, K, Na, Ca 순으로 Zn이 특히 가장 많았고 Cu는 검출되지 않았다. 실험분석한 전(全)미량금속원소(Cd는 제외)가 가장 많이 함유된 버섯은 붉은산무명버섯이었고 그 다음이 자주방망이버섯아재비, 벚꽃버섯, 자주방망이버섯, 뽕나무버섯, 뽕나무버섯부치의 순이었다. 6종의 버섯중 가장 많이 함유된 미량금속원소는 Zn이었고 그 다음이 K, Fe, Na, Mn, Cu, Ca 순이었다. Cd는 채집장소인 서울산업대, 광릉, 동구릉, 설악산 순으로 설악산에서 채집한 벚꽃버섯, 붉은산무명버섯에 가장 적은 분석치(흔적량)을 얻었다.

• 한국재료학회지
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• 제21권10호
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• pp.563-567
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• 2011

We report the structural characterization of $Bi_xZn_{1-x}O$ thin films grown on c-plane sapphire substrates by plasma-assisted molecular beam epitaxy. By increasing the Bi flux during the growth process, $Bi_xZn_{1-x}O$ thin films with various Bi contents (x = 0~13.17 atomic %) were prepared. X-ray diffraction (XRD) measurements revealed the formation of Bi-oxide phase in (Bi)ZnO after increasing the Bi content. However, it was impossible to determine whether the formed Bi-oxide phase was the monoclinic structure ${\alpha}-Bi_2O_3$ or the tetragonal structure ${\beta}-Bi_2O_3$ by means of XRD ${\theta}-2{\theta}$ measurements, as the observed diffraction peaks of the $2{\theta}$ value at ~28 were very close to reflection of the (012) plane for the monoclinic structure ${\alpha}-Bi_2O_3$ at 28.064 and the reflection of the (201) plane for the tetragonal structure ${\beta}-Bi_2O_3$ at 27.946. By means of transmission electron microscopy (TEM) using a diffraction pattern analysis and a high-resolution lattice image, it was finally determined as the monoclinic structure ${\alpha}-Bi_2O_3$ phase. To investigate the distribution of the Bi and Bi-oxide phases in BiZnO films, elemental mapping using energy dispersive spectroscopy equipped with TEM was performed. Considering both the XRD and the elemental mapping results, it was concluded that hexagonal-structure wurtzite $Bi_xZn_{1-x}O$ thin films were grown at a low Bi content (x = ~2.37 atomic %) without the formation of ${\alpha}-Bi_2O_3$. However, the increased Bi content (x = 4.63~13.17 atomic %) resulted in the formation of the ${\alpha}-Bi_2O_3$ phase in the wurtzite (Bi)ZnO matrix.

• Journal of Nutrition and Health
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• 제8권1호
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• pp.39-46
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• 1975

This studies were designed to know the contents of trace element and magnesium in cereals. Twenty two kinds of cereal, 104'samples, were analyzed by atomic absorption spectrophotometer for the determination of Manganese, Iron, Magnesium, Chrome, Cupper, Nickel, Zinc, Stannous, Lead and Cadmium. The results are as follows: 1) The contents of Mn and Fe in the sesame group show highest value and next is bean group. In the rice group its content shows lowest value than other cereals. 2) In the Cr content its value is lower than other elements in cereals respectively. Cr content of sesame and bean group show higher than rice and barley group. 3) The contents of Cu and Ni in the sesame and bean group show higher value than the value of rice and barley group. Its contents of rice and barley group is almost equal in Cu and Ni. 4) For the Zn content the value of sesame group is higher than other cereals and next is bean group. In the Sn content the value of bean group shows higher one than other cereals. The contents of Zn and Sn in rice and barley group are lower than other cereals. 5) The value of Pb is almost equal to each cereal. The content of Cd in bear group and barley group show higher than other cereals and its value of rice group is equal to the value of barley group.