• Journal of the Korean Applied Science and Technology
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• v.9 no.2
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• pp.165-174
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• 1992

The standardized activated sludge for the biodegradation test of anion surfactants has been produced from the collected microorganisms in the soil and the wastewaters treatment plant. The activated sludge was kept under control of the pH, dissolved oxygen, microorganisms and inoculated the basal medium flasks with LAS and LAS mixed with heavy metals [Cd(II), Cu(II), Zn(II)]. Based of results, the inhibition effect(%) of heavy metals in LAS biodegradation were 1. All 1% when LAS 30mg/l-Cd(II), Cu(II) and Zn(II) 0.1mg/l, respectively 2. All 1${\sim}$10% when LAS 30mg/l-Cd(II), Cu(II) and Zn(II) 1mg/l, respectively 3. All 10${\sim}$40% when LAS 30mg/l-Cd(II), Cu(II) and Zn(II) 10mg/l, respectively 4. All 30${\sim}$65% when LAS 30mg/l-Cd(II), Cu(II) and Zn(II) 100mg/l, respectively And toxicity order of heavy metals to the microorganisms in LAS biodegradation were Cd>Cu>Zn in low concentration(0.1${\sim}$1mg/l)and Cd>Zn>Cu in high concentration(10${\sim}$100mg/l).

• Journal of the Korean institute of surface engineering
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• v.40 no.1
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• pp.11-15
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• 2007

Stable metallic Cu/Zn nanoparticles were prepared in the base oil phase by hydrothermal method. The physical properties, such as crystal structure, crystallite size and crystallinity according to synthesis conditions have been investigated by XRD, FT-IR and TEM. In addition, 4-ball test has been performed in order to investigate the frictional wear properties of prepared nanosized Cu/Zn particles. The peaks of the X-ray diffraction pattern indicate that the particle size was very small and crystallinity of Cu/Zn particles was good. The micrographs of TEM showed that nanosized Cu/Zn particles possessed a spherical morphology with a narrow size distribution. The crystallite size of the Cu/Zn particles synthesized in base oils was 23-30 nm. It was found that the antiwear capacity increases with increasing Cu/Zn concentration. When the concentration of Cu/Zn was 5.0 wt%, the wear scar diameters was 0.38 mm.

• Korean Journal of Agricultural Science
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• v.51 no.1
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• pp.53-61
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• 2024

A total of 180 21-day-old weaning pigs ([Yorkshire × Landrace] × Duroc) with an initial body weight of 6.44 ± 0.01 kg were randomly assigned to 9 treatments for evaluating the effects of replacing dietary inorganic copper (Cu) and zinc (Zn) with glycine (Gly) or methionine (Met)-chelated Cu and Zn on growth performance and nutrient digestibility. The experimental period was 35 days. There were four replicated pens per treatment, with five pigs (three males and two females) per pen. Dietary treatments consisted of a basal diet (CON), in which the sources of Cu and Zn were in inorganic form. The inorganic Cu and Zn in the basal diet were replaced by glycine-chelated (GC) and methionine-chelated (MC) Cu and Zn by 30, 50, 70, or 100% to form the GC1, GC2, GC3, GC4, or MC1, MC2, MC3, MC4 groups. The 100% replacement of dietary inorganic Cu and Zn with GC or MC increased (p < 0.05) average daily gain, average daily feed intake, and gain-to-feed ratio. The complete replacement of dietary inorganic Cu and Zn with GC or MC led to enhanced (p < 0.05) digestibility of dry matter, nitrogen, Cu and Zn. Thus, the replacement of inorganic Cu and Zn with GC or MC can improve the growth efficiency and nutrient utilization of weaning pigs.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.405-405
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• 2012

에너지 갭의 크기가 큰 ZnO는 큰 여기자 결합과 높은 화학적 안정도를 가지고 있기 때문에 전자소자 및 광소자로 많이 응용되고 있다. ZnO는 광학적 및 전기적 성질의 여러 가지 장점 때문에 메모리, 나노발전기, 트랜지스터, 태양전지, 광탐지기 및 레이저와 같은 여러 분야에 많이 사용되고 있다. Zn와 쉘 구조가 비슷한 Cu 불순물은 우수한 luminescence activator이고 다양한 불순물 레벨을 만들기 때문에 전기적 및 광학적 특성을 변화하는데 좋은 도핑 물질이다. Cu가 도핑된 ZnO 나노구조를 전기화학적 증착법을 이용하여 형성하고, 형성시간의 변화에 따른 구조적 및 광학적 성질에 대한 관찰하였다. ITO 코팅된 유리 기판에 전기화학증착법을 이용하여 Cu 도핑된 ZnO를 성장하였다. Sputtering, pulsed laser vapor deposition, 화학기상증착, atomic layer epitaxy, 전자빔증발법 등으로 Cu 도핑된 ZnO 나노구조를 형성하지만 본 연구에서는 낮은 온도와 간단한 공정으로, 속도가 빠르고 가격이 낮아 경제적인 면에서 효율적인 전기 화학증착법으로 성장하였다. 반복실험을 통하여 Cu의 도핑 농도는 Zn과 Cu의 비율이 97:3이 되도록, ITO 양극과 Pt 음극의 전위차가 -0.75V로 실험조건을 고정하였고, 성장시간을 각각 5분, 10분, 20분으로 변화하였다. 주사전자현미경 사진에서 Cu 도핑된 ZnO는 성장 시간이 증가함에 따라 나노세선 형태에서 나노로드 형태로 변하였다. X-선 회절 측정결과에서 성장시간이 변화함에 따라 피크 위치의 변화를 관찰하였다. 광루미네센스 측정 결과는 Oxygen 공핍의 증가로 보이는 500~600 nm 대의 파장에서 나타난 피크의 위치가 에너지가 큰 쪽으로 증가하였다. 위 결과로부터 성장 시간에 따른 Cu 도핑된 ZnO의 구조적 및 광학적 특성변화를 관찰하였고, 이 연구 결과는 Cu 도핑된 ZnO 나노구조 기반 전자소자 및 광소자에 응용 가능성을 보여주고 있다.

• Journal of The Korean Society of Grassland and Forage Science
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• v.24 no.4
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• pp.271-280
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• 2004

This pot experiment was conducted to investigate the effects of systematic variation appling of Fe, Mn, Cu, and Zn on forage performance of orchardgrass and white clover. The treatments of systematic variation were 0/100, 25/75, 50/50, 75/25, and $100/0\%$ in the Fe/Cu(trial-1), Mn/Zn(trial-2), and Fe+Cu/Mn+Zn(trial-3), respectively. The treatments of Fe/Mn/Cu/Zn(trial-4) were $70\%$ in main-element and $10\% in other 3 sub-elements, respectively. 1. Compared with orchadgrass, white clover showed relatively consistent differences in the content of micronutrients as influenced by treatments of the systematic variation. The contents of Mn and Cu in the forages were significantly influenced by the application rates of Mn and Cu, respectively. The contents of Fe and Zn in the forages, however, were not significantly different among these treatments. 2. Compared with orchardgrass in the Fe/cu trial, white clover had not only the low content of Cu but also the Cu content and yield of white clover were greatly decreased by the low rate of application of Cu. In the Mn/Zn trial, the $0/100\%$ resulted in the severe decrease of Mn-content in both forages. The low content of Mn in white clover tended to be negatively correlated to the Mn-chlorosis, inferior growth and flowering, and low yield. 3. In the Fe+Cu/Mn+Zn trial, the application with $0/100\%$ and $0/100\%$ resulted in the relatively great decrease of Cu and Mn contents, respectively. These traits in white clover tended to be negatively correlated to the inferior growth and flowering, and low yield 4. In the Fe/Mn/Cu/Zn trial, the content of every main-elements in the forages were increased especially in Mn. In addition, the contents of sub-elements were likely to be somewhat negatively influenced by the treatment of main-element respectively.

• Korean Journal of Environmental Agriculture
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• v.9 no.2
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• pp.113-119
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• 1990

The germination and growth of radish and chiness cabbage in soils treated with Cr, Ni, Cd, Cu, and Zn at 20, 50, 100 and 200 ppm were determined. The germination of radish and chiness cabbage in soils was greatly affected by addition of Ni and Cr at 200 ppm, but almost not at all by treatment with Cd, Cu, and Zn even 200 ppm. The injury to the growth of crops was generally the highest with Cr, followed by Ni, Cd, Cu, and Zn, and more with chiness cabbage with radish. Serious crop injury appeared at 20 ppm of Cr, 50 ppm of Ni, Cd and Cu, and 200 ppm of Zn on radish, and at 20 ppm of Cr, Ni, Cd and Cu, and 200ppm of Zn of chiness cabbage. However, crop inhibition decreased greatly with addition of compost and lime.

• Molecules and Cells
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• v.21 no.1
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• pp.161-165
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• 2006

Dichlorodihydrofluorescein ($DCFH_2$) is a widely used probe for intracellular $H_2O_2$. However, $H_2O_2$ can oxidize $DCFH_2$ only in the presence of a catalyst, whose identity in cells has not been clearly defined. We compared the peroxidase activity of Cu,Zn-superoxide dismutase (CuZnSOD), cytochrome c, horseradish peroxidase (HRP), $Cu^{2+}$, and $Fe^{3+}$ under various conditions to identify an intracellular catalyst. Enormous increase by bicarbonate in the rate of $DCFH_2$ oxidation distinguished CuZnSOD from cytochrome c and HRP. Cyanide inhibited the reaction catalyzed by CuZnSOD but accelerated that by $Cu^{2+}$ and $Fe^{3+}$. Oxidation of $DCFH_2$ by $H_2O_2$ in the presence of a cell lysate was also enhanced by bicarbonate and inhibited by cyanide. Confocal microscopy of $H_2O_2$-treated cells showed enhanced DCF fluorescence in the presence of bicarbonate and attenuated fluorescence for the cells pre-incubated with KCN. Moreover, DCF fluorescence was intensified in CuZnSOD-transfected HaCaT and RAW 264.7 cells. We propose that CuZnSOD is a potential intracellular catalyst for the $H_2O_2$-dependent oxidation of $DCFH_2$.

• Korean Journal of Soil Science and Fertilizer
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• v.31 no.2
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• pp.107-113
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• 1998

We investigated the effects of a long term application of soil amendments such as lime, silicate, compost, or combinations of these materials on the contents of Cu and Zn in paddy soil and brown rice. The results obtained from a sequential extraction of Cu and Zn in paddy soils and brown rice, using $H_2O$, $KNO_3$, $Na_2$-EDTA and $HNO_3$ and showed that the most of Cu and Zn were NaOH-extractable (organically bound form) and $HNO_3$-extractable (sulfide and residual form). Cu contents of NaOH and EDTA extractable increased with the long term application of compost while the contents of Zn extracted by $KNO_3$ was decreased even though $HNO_3$ extractable-Zn was prominent chemical form in paddy soils. The percentage and contents of Zn, extracted by $KNO_3$ for each combination treatment of soil amendments, was decreased but the contents of Cu was not affected. The content of NaOH extractable-Cu was proportionally increased with increase in organic matter content irrespective of the extractants used in this experiment. The contents of Zn and exchangeable K were also increased with increase in organic matter content. However, we could not find any relationship between the extractable forms of Cu and Zn, and CEC, OM. while increase in CEC, contents of cations, and organic matter decreased the content of Cu in brown rice.

• Korean Journal of Environmental Agriculture
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• v.12 no.2
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• pp.105-111
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• 1993

This study was carried out to find heavy metal contents in soil and in native plant in the regions near by zinc-mines, located at the Chilgok and Uljin Gun in Kyeongpook area. In the heavy metal contents during the to growth of native plants, Cd was contained in the order perennial > biennial > annual plant, but Cu was annual > perennial > biennial plant, and there was no difference in Zn contents. The native plants contained heavy metal highest were Osmunda japonica in Cd, Persicaria thunbergii H.G in Cu and Equisetum arvense L. in Zn. Cd was contained highest in Pteridaceae, Cu in Equisetaceae and Zn in Polygonaceae. In the heavy metal contents by the part of plant of Equisetum arvense L. and Erigeron canadensis, Cd and Zn were much contained in the order leaf > stem > root, but Cu was in the order root > leaf > stem. The average contents of Cd, Cu, Zn in soil were 1.27ppm. 12.04ppm. 64.28ppm in Chilgok, and 3.30ppm. 72.93ppm. 194.04ppm in Uljin respectively. There were positive correlations between Cd contents of heavy metals(Cd, Cu, Zn) in soil and in native plant, but not significant. It was estimated that Osmunda japonica, Pteridium aquilinum (KUHN) var and Equisetum arvense L. which most absorbed heavy metal have effect of exclusion of heavy metals near by zine-mines region.

• Journal of the Korean Society for Marine Environment & Energy
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• v.19 no.3
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• pp.203-210
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• 2016

In this study, nine heavy metals were analyzed in seaweeds collected from market and laver culture farm of Korea and a food safety assessment were also carried out for these heavy metals. The level of heavy metal concentrations in seaweeds was in the following order: Fe>As>Zn>Cu>Cd>Pb>Cr>Ni>Hg. Except for zinc and cadmium, seven heavy metals were significantly higher in cultured laver than in processed laver. Significant correlation was observed Cr-Fe in cultured laver and Cu-Zn, Cd-Cu, Cd-Zn and Pb-Ni in processed laver and Cu-Cr, Cu-Zn, Cd-Cr and Ni-Fe in sea tangle and Zn-Fe, Cr-Fe, Cr-Zn, Cd-Ni, Cu-Cd and Cu-Pb in processed sea mustard. Considering differences in heavy metal concentration between processed laver and cultured laver and in correlation among heavy metals, removal efficiency of heavy metals may be attributed to seaweed treatment process. The average weekly intakes of Cu, Cd, Zn, Fe and Hg via seaweeds consumption were about 0.1~7.6% of PTWI (Provisional Tolerable Weekly Intakes). Therefore, it was found that heavy metals in the seaweeds were very safe for consumption.