• 생태와환경
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• 제50권1호
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• pp.16-28
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• 2017

In an aquatic environment, toxicity of metals to organisms depends on external factors (type of metal, exposure concentration and duration, environmental parameters, and water quality) and intracellular processes(metal-binding sites and detoxification). Toxicity of copper(Cu) on the marine microalga Tetraselmis suecica was investigated in this study. Dose-dependent (Cu concentration dependent) inhibition of growth and cell division, as well as, variation of intra- and extra-cellular Cu, Fe and Zn content was observed. T. suecica was sensitive to Cu; the 96 h $EC_{50}$ (concentration to inhibit growth-rate by 50%) of growth rate (${\mu}$) ($21.73{\mu}M\;L^{-1}$), cell division $day^{-1}$ ($18.39{\mu}M\;L^{-1}$), and cells $mL^{-1}$ ($13.25{\mu}M\;L^{-1}$) demonstrate the toxicity of Cu on this microalga. High intra-($19.86Pg\;cell^{-1}$) and extra-cellular($54.73Pg\;cell^{-1}$) Cu concentrations were recorded, on exposure to 24.3 and $72.9{\mu}M\;L^{-1}$ of Cu.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 C
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• pp.1832-1834
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• 2005

In the electrical equipments, there are lots of phenomena such as loosening of connectin parts, So, heat generation and oxidation growth is considered to have a possibility to cause fire. In this Paper, we were carried out to study the oxidation growth and voltage waveform of connecting parts. In case of copper and copper connection, the growing of Cu2O elongated more than the other copper alloys. According to oxidation growth, the voltage waveform is distorted. And the contact voltage and the power dissipation increased rapidly.

• 한국재료학회지
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• 제34권3호
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• pp.163-169
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• 2024

As the limitations of Moore's Law become evident, there has been growing interest in advanced packaging technologies. Among various 3D packaging techniques, Cu-SiO₂ hybrid bonding has gained attention in heterogeneous devices. However, certain issues, such as its high-temperature processing conditions and copper oxidation, can affect electrical properties and mechanical reliability. Therefore, we studied depositing only a heterometal on top of the Cu in Cu-SiO₂ composite substrates to prevent copper surface oxidation and to lower bonding process temperature. The heterometal needs to be deposited as an ultra-thin layer of less than 10 nm, for copper diffusion. We established the process conditions for depositing a Co film using a Co(EtCp)₂ precursor and utilizing plasma-enhanced atomic layer deposition (PEALD), which allows for precise atomic level thickness control. In addition, we attempted to use a growth inhibitor by growing a self-assembled monolayer (SAM) material, octadecyltrichlorosilane (ODTS), on a SiO₂ substrate to selectively suppress the growth of Co film. We compared the growth behavior of the Co film under various PEALD process conditions and examined their selectivity based on the ODTS growth time.

• Journal of Magnetics
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• 제11권3호
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• pp.111-114
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• 2006

We electroplated copper-cobalt thin films on a silicon substrate, which had 150 nm thick copper seed layer. The adhesion between the two metallic layers could be increased by utilizing a proper organic additive, pulse plating technique, and high temperature annealing. The thin films exhibited columnar growth of the deposits and enhanced adhesion. This is attributed to the grain growth mechanism introduced by the additive and annealing.

• 식물병연구
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• 제11권2호
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• pp.115-121
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• 2005

본 연구는 2003년부터 2005년까지 감귤원에서 구리제의 효율적인 사용을 위하여 주요 감귤 병에 대한 구리제의 방제 효과, 구리피해 발생시기 및 구리제 종류 별 구리피해 정도, 그리고 기계유유제와의 혼용에 대한 효과를 구명하고자 실시하였다. 결과를 종합하면 감귤더뎅이병에 대한 방제효과는 구리제 종류에 관계없이 방제가가 약 $75\%$, 궤양병에 대해서도 $85\~88\%$, 그리고 검은점무늬병에 대해서는 약 $75\~86\%$이었다. 구리피해는 새순이 어릴수 록 발생이 심하였고 과일의 경우 고온기인 7월부터 8월까지가 가장 심하였다. 또한 구리제에 응애 방제용 기계유유제를 혼용하여 살포할 경우 방제 효과는 그대로 유지하였지만 구리피해는 상당히 감소하였으며 이들 결과들로부터 구리제와 기계유유제를 혼용하여 적기에 사용할 경우 봄철 더뎅이병과 궤양병, 그리고 응애를 동시에 방제할 수 있으며 유기농이나 무농약 재배 과원에서도 효율적으로 사용할 수 있을 것으로 생각된다.

• 한국재료학회지
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• 제17권1호
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• pp.56-59
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• 2007

Recently, requirement for the ultra thin copper foil increases with smaller and miniaturized electronic components. In this study, we evaluated the surface morphology, crystal phase ana surface roughness of the copper film electrodeposited by pulse method without using additives. Homogeneous and dense copper crystals were formed on the titanium substrate, and the optimum condition was 25% duty cycle. Moreover, the surface roughness(Ra), $0.295{\mu}m$, is the smallest value in this condition. It is thought that this copper foil is good for electromigration inhibition due to the preferential crystal growth of Cu (111)

• 한국표면공학회지
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• 제32권3호
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• pp.244-248
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• 1999

Photoelectrodeposition of copper on semiconductive B-doped diamond films was investigated. There are cleasr morphology differences between photodeposited copper and electrodeposited copper. Photoelecrodeposition proceeded as uniform 2-dimensional growth. On the other hand electrodeposition proceeded as scarce random deposition. By applying this effect we have succeeded in forming a conductive pattern on semiconductive B-doped diamond with the aid of a photo-mask. And it was suggested that the surface reforming caused by photoelectrochemical process could be easily detected by the following metal (copper) deosition method, which is demonstrated as 'Diamond photographic phenomenon'.

• 한국가금학회지
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• 제20권2호
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• pp.55-64
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• 1993

본 실험은 육용계 기초사료에 copper와 Vit. E＋Se을 첨가급여시 육계의 혈청 IgG수준과 증체량 및 질병 발생율과의 상관관계를 조사함으로써 가금의 영양과 면역반응에 관한 기초적인 정보를 얻고자 실시하였다. 닭의 혈청중 IgG함량을 처리별, 시기별로 RID test에 의해 측정한 후 이를 증체량 및 건강상태와 비교한 결과는 다음과 같다. 1. 대조구의 혈청중 IgG함량은 부화 직후에 최고치 (4.26mg/$m\ell$)를 나타내었으며 2주령까지 급격히 감소하여 최소치 (0.87mg/$m\ell$)를 유지하다가 그후에 점차적으로 증가하여, 7주령에는 2.48mg/$m\ell$의 수준을 보였다. 2. 혈청 IgG의 농도와 증체량과의 상관성은 사육전기에는 고도의 유의적인 부의 상관관계를 보였으며 3주령에서 가장 높은 상관계수(r＝-0.423)를 나타냈으며 사육후기에는 정의 상관관계를 나타내어 7주령시의 IgG농도와 3주령시 증체량간에는 r＝＋0.246의 상관계수를 보였다. (p＜0.01) 3. Cul5, Cu25와 ES2O군의 혈청 IgG수준은 2주령에서 대조군에 비하여 낮은 수준을 보이다가 3주령에는 급속히 상승한 반면에 대조군에서는 이와 같은 현상이 1주일 늦게 나타났다. 이는 Cu나 Vit. E와 Se을 혼합 첨가 급여할 경우에는 능동면역의 발달이 대조군보다 1주일 조기에 일어나는 것으로 판단된다. 4. Cu15와 Cu25의 증체량은 대조군보다 높은 수준을 나타내었다. 특히 4주령시 증체율은 대조군에 비하여 4.8%와 4.5%높았다. ES2O군의 증체효과는 없었으며 ES 40군은 대조군보다 유의적으로 낮은 증체유을 보였다. 5. Cul5, Cu25, ES2O, ES4O군은 대조군에 비하여 높은 건강 수준을 유지하였으며 폐사율은 각각 1.9%, 1.9%, 2.9%와 1.0%로써 대조군의 4.8%에 비하여 낮은 수준을 보여 질병에 대한 저항능력이 향상되었다.

• Asian-Australasian Journal of Animal Sciences
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• 제9권4호
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• pp.359-362
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• 1996

A study was conducted to assess the influence of copper on the total sulphur amino acid requirements of broiler chickens reared under two growing periods. The TSAA levels used were 0.73, 0.83, 0.93% with copper levels of 0, 125, 250 and 375 mg/kg for the starter period and the TSAA levels of 0.72, 0.79 and 0.86% with copper levels of 0, 125, 250 and 375 mg/kg for the grower period. Total feed consumption, body weight gain and feed L gain ratio were used as the parameters for the assessment. The results showed that adding copper at 250 mg/kg to the diets improved feed : gain ratio of the starter broilers and resulted in small improvement of body weight gain and feed : gain ratio of the grower broilers. Growth was depressed in relation to the reduction of feed intake on the chicks fed diet containing 375 mg/kg copper. There was a significant interaction between dietary TSAA and copper levels for feed intake, hence, indicating that the supplementation of copper at the level of 375 mg/kg increased the TSAA requirement of the starter broilers, although no interference with the requirement of grower broilers.

• Asian-Australasian Journal of Animal Sciences
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• 제12권4호
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• pp.548-553
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• 1999

An experiment was conducted to study the effects of high dietary copper supplementation on the gastrointestinal tract morphology of broiler chickens. Eighty 3-week-old broiler chicks were divided randomly into eight groups of four dietary treatments and over three week were fed isoenergetic and isonitrogenous diets that contained 0, 100, 250, or 500 mg/kg of supplemental copper from cupric sulfate. The copper supplementation in the broiler diet up to 250 mg/kg did not significantly influence broilers' performance. A high dietary copper supplementation of 500 mg/kg did significantly depress growth and feed conversion in the broilers (p<0.05). Copper supplementation more than 250 mg/kg in the broiler diet significantly influenced the morphology of the GI tract, as shown by severe oral lesions and gizzard erosion. It also significantly depressed the villi height and significantly thickened the muscular layer in the duodenum (p<0.05). The severely damaged villi were observed by scanning electronic microscope from the duodenum samples of broilers fed a 500 mg/kg copper supplemented diet. The 500 mg/kg copper supplemented diet also significantly influenced the plasma constituents. Plasma glucose concentration was significantly depressed (p<0.05).