벼 종자배양에서 Copper가 캘러스 형성 및 식물체 재분화에 미치는 영향

권용삼,손재근 한국식물생명공학회 2001 식물생명공학회지 Vol.28 No.4

벼의 종자배양에서 식물체 재분화 능력을 향상시키기 위하여 2 mg/L의 2,4-D와 여러 가지 농도의 copper (0~5.0mg/L)가 첨가된 MS배지에 종자배양 한 바 캘러스 생장정도는 copper 농도에 따라 다르게 나타났는데 특히, 2.5 mg/L의 copper가 첨가된 배지에서 가장 양호하였다. 그리고 캘러스 형성률과 copper 농도 간에는 유의성 있는 차이가 인정되지 않았다. 식물체 재분화 배지에 2.5 mg/L의 copper의 첨가는 Indica 품종들의 식물체 재분화 효율을 크게 향상시켰다. Copper가 첨가되지 않은 N$_{6}$배지에서 Indica 6품종의 평균재분화율은 2.4%이었으나, copper가 첨가된 배지에서 27.4%로 높게 나타났다. This study was conducted to improve the regeneration efficiency from seed-derived calli of rice by optimizing the copper concentrations in the media. Mature seeds were cultured on MS medium supplemented with copper sulphate (0 to 5.0 mg/L) and 2 mg/L 2,4-D. Callus growth was influenced by the levels of copper sulphate containing with medium, The addition of copper sulphate (2.5 mg/L) in regeneration medium enhanced dramatically the ability of plant regeneration from seed-derived calli. The mean frequency of plant regeneration of 6 indica rices was 27.4% on medium containing copper sulphate, whereas that of the cultivars on copper-free medium was 2.4%. These results suggest that copper sulphate may have an important role in improving regeneration ability of indica rices.

Original Articles : Comparison of the bioavailability of nano- and micro-sized copper oxide particles in copper-deficient mice

( Ja Ktyung Seol ),( Jae Hwang Jeong ),( Sang Yoon Nam ),( Young Won Yun ),( Jong Soo Kim ),( Beom Jun Lee ) 한국예방수의학회(구 한국수의공중보건학회) 2015 예방수의학회지 Vol.39 No.1

Abstract: Copper is an essential micronutrient whose deficiency is often seen to occur in humans. Although many biomedicalstudies have focused on the use of nanoparticles, the nutritional effects of nano-sized copper oxide particles are not wellknown. This aim of this study was to investigate the nutritional bioavailability of nano- and micro-sized copper oxide (CuO)particles in copper-deficient (CuD) mice. Copper deficiency was induced in mice by feeding a CuD diet (0.93 mg Cu/kg diet)for 7 weeks. After the induction of copper deficiency, nano- or micro-sized copper oxide particles were administered orallyat two different doses (0.8 and 4.0 mg CuO/kg body weight) to mice in the following groups: (1) normal control (NC), (2)CuD, (3) low dose micro-sized CuO, (4) high dose micro-sized CuO, (5) low dose nano-sized CuO, and (6) high dosenano-sized CuO. The hepatic copper concentration in the CuD group was significantly lower than that in the NC group. Compared to the NC group, the CuD group exhibited lower serum ceruloplasmin (CP) activity and CP level. Thecopper/zinc-superoxide dismutase activity in the CuD group was significantly lower than that in the NC group. Treatment withnano- or micro-sized copper oxide particles for 2 weeks restored the hepatic copper levels and serum CP activities to valuessimilar to those observed in the NC group. The CP levels and copper/zinc-superoxide dismutase activities in all the copperoxide treatment groups also recovered to normal values after 3 weeks of copper oxide treatment. These results show thatoral administration of either nano- or micro-sized copper oxide particles for 2?3 weeks restored the normal condition inpreviously CuD mice.

APPLICATION OF COLD SPRAY COATING TECHNIQUE TO AN UNDERGROUND DISPOSAL COPPER CANISTER AND ITS CORROSION PROPERTIES

이민수,최희주,최종원,김형준 한국원자력학회 2011 Nuclear Engineering and Technology Vol.43 No.6

A cold spray coating (CSC) of copper was studied for its application to a high-level radioactive waste (HLW) disposal canister. Several copper coatings of 10 mm thick were fabricated using two kinds of copper powders with different oxygen contents, and SS 304 and nodular cast iron were used as their base metal substrates. The fabricated CSC coppers showed a high tensile strength but were brittle in comparison with conventional non-coating copper, hereinafter defined to as “commercial copper”. The corrosion behavior of CSC coppers was evaluated by comparison with commercial coppers, such as extruded and forged coppers. The polarization test results showed that the corrosion potential of the CSC coppers was closely related to its purity; low-purity (i.e., high oxygen content) copper exhibited a lower corrosion potential, and highpurity copper exhibited a relatively high corrosion potential. The corrosion rate converted from the measured corrosion current was not, however, dependent on its purity: CSC copper showed a little higher rate than that of commercial copper. Immersion tests in aqueous HCl solution showed that CSC coppers were more susceptible to corrosion, i.e., they had a higher corrosion rate. However, the difference was not significant between commercial copper and high-purity CSC copper. The decrease of corrosion was observed in a humid air test presumably due to the formation of a protective passive film. In conclusion, the results of this study indicate that CSC application of copper could be a useful option for fabricating a copper HLW disposal canister.

Comparison of the bioavailability of nano- and micro-sized copper oxide particles in copper-deficient mice

Ja-Kyung Seol,정재황,Sang-Yoon Nam,윤영원,Jong-Soo Kim,이범준 한국예방수의학회 2015 예방수의학회지 Vol.39 No.1

Abstract: Copper is an essential micronutrient whose deficiency is often seen to occur in humans. Although many biomedicalstudies have focused on the use of nanoparticles, the nutritional effects of nano-sized copper oxide particles are not wellknown. This aim of this study was to investigate the nutritional bioavailability of nano- and micro-sized copper oxide (CuO)particles in copper-deficient (CuD) mice. Copper deficiency was induced in mice by feeding a CuD diet (0.93 mg Cu/kg diet)for 7 weeks. After the induction of copper deficiency, nano- or micro-sized copper oxide particles were administered orallyat two different doses (0.8 and 4.0 mg CuO/kg body weight) to mice in the following groups: (1) normal control (NC), (2)CuD, (3) low dose micro-sized CuO, (4) high dose micro-sized CuO, (5) low dose nano-sized CuO, and (6) high dosenano-sized CuO. The hepatic copper concentration in the CuD group was significantly lower than that in the NC group. Compared to the NC group, the CuD group exhibited lower serum ceruloplasmin (CP) activity and CP level. Thecopper/zinc-superoxide dismutase activity in the CuD group was significantly lower than that in the NC group. Treatment withnano- or micro-sized copper oxide particles for 2 weeks restored the hepatic copper levels and serum CP activities to valuessimilar to those observed in the NC group. The CP levels and copper/zinc-superoxide dismutase activities in all the copperoxide treatment groups also recovered to normal values after 3 weeks of copper oxide treatment. These results show thatoral administration of either nano- or micro-sized copper oxide particles for 2–3 weeks restored the normal condition inpreviously CuD mice.

Evaluation of copper alloys for reducing infection by methicillin resistant Staphylococcus aureus and vancomycin resistant Enterococcus faecium in intensive care unit and in vitro

( Sung Im Choi ),( Mee Soo Chang ),( Taeeun Kim ),( Kyung Hwa Chung ),( Seongman Bae ),( Sung-han Kim ),( Chan Jin Yoon ),( Young Kyoon Kim ),( Jun Hee Woo ) 대한내과학회 2021 The Korean Journal of Internal Medicine Vol.36 No.5

Background/Aims: Multi-drug resistant pathogens are increasing among health-care-associated infections. It is well known that copper and copper alloys have antimicrobial activity. We evaluated the activity of copper against bacteria in a hospital setting in Korea. Methods: This study was conducted in a laboratory and medical intensive care unit (ICU). Methicillin resistant Staphylococcus aureus (MRSA) and vancomycin resistant Enterococcus faecium (VRE) were inoculated onto copper, copper alloy and stainless steel plates. After 24 hours of incubation, colony-forming units (CFU) were counted in the laboratory. Two similar rooms were chosen in the ICU; one room had copper-containing surface, and the other room contained items with a stainless steel surfaces. Items were sampled weekly for 8 weeks when the rooms were not crowded and when the rooms were busier with healthcare workers or visitors. Results: In vitro time-kill curves showed copper or, a copper alloy yielded a significant reduction in MRSA and VRE CFUs over 15 minutes. Upon exposure to stain-less steel plates, CFUs were slowly reduced for 24 hours. In vivo, MRSA CFUs were lower in rooms with copper-containing surfaces compared with controls, both after cleaning and after patients had received visitors (p < 0.05). Analysis of VRE revealed similar results, but VRE CFUs from copper-containing surfaces of drug carts in the ICU did not decrease significantly. Conclusions: Copper has antimicrobial activity and appears to reduce the number of multi-drug resistant microorganisms in a hospital environment. This finding suggests the potential of the use of copper fittings, instruments and surfaces in hospital.

구리 질화막을 이용한 구리 접합 구조의 접합강도 연구

서한결,박해성,김가희,박영배,김사라은경,Seo, Hankyeol,Park, Haesung,Kim, Gahui,Park, Young-Bae,Kim, Sarah Eunkyung 한국마이크로전자및패키징학회 2020 마이크로전자 및 패키징학회지 Vol.27 No.3

최근 참단 반도체 패키징 기술은 고성능 SIP(system in packaging) 구조로 발전해 가고 있고, 이를 실현시키기 위해서 구리 대 구리 접합은 가장 핵심적인 기술로 대두되고 있다. 구리 대 구리 접합 기술은 아직 구리의 산화 특성과 고온 및 고압력 공정 조건, 등 해결해야 할 문제점들이 남아 있다. 본 연구에서는 아르곤과 질소를 이용한 2단계 플라즈마 공정을 이용한 저온 구리 접합 공정의 접합 계면 품질을 정량적 접합 강도 측정을 통하여 확인하였다. 2단계 플라즈마 공정은 구리 표면에 구리 질화막을 형성하여 저온 구리 접합을 가능하게 한다. 구리 접합 후 접합 강도 측정은 4점 굽힘 시험법과 전단 시험법으로 수행하였으며, 평균 접합 전단 강도는 30.40 MPa로 우수한 접합 강도를 보였다. The recent semiconductor packaging technology is evolving into a high-performance system-in-packaging (SIP) structure, and copper-to-copper bonding process becomes an important core technology to realize SIP. Copper-to-copper bonding process faces challenges such as copper oxidation and high temperature and high pressure process conditions. In this study, the bonding interface quality of low-temperature copper-to-copper bonding using a two-step plasma treatment was investigated through quantitative bonding strength measurements. Our two-step plasma treatment formed copper nitride layer on copper surface which enables low-temperature copper bonding. The bonding strength was evaluated by the four-point bending test method and the shear test method, and the average bonding shear strength was 30.40 MPa, showing that the copper-to-copper bonding process using a two-step plasma process had excellent bonding strength.

Electrolysis of Copper and Recovery of High Purity Copper using Wastewater Generated in Plating Process

( Minsoo Kim ),( Sanghyuk Han ),( Jiwoong Jeon ),( Sangwoon Woo ),( Jun Won Yang ),( Sungyoon Park ),( Yejee Lim ),( Nway Oo Khin ),( Jimin Yu ),( Han S. Kim ) 한국폐기물자원순환학회(구 한국폐기물학회) 2019 ISSE 초록집 Vol.2019 No.-

To date, demand for valuable metals continuously increasing due to electronic industries in Korea, and as a result, the generation of wastes are dramatically increasing. Along with aluminum, copper is one of the most demanding metals in most industries, and therefore, their recovery and recycling have received extensive interests. High-purity copper is critically required for electronic and electrical industries. A number of purification processes have been developed for the purity level-up of low-degree copper recycling resources. In this study, copper was recovered from acidic wastewaters generated in plating processes by electrolysis. Copper extraction was conducted in a 1.5L batch type reactor (90×120×170 mm, L×W×H) made of plexiglass. Cathode was made of a stainless-steel plate and anode was prepared by coating iridium/ruthenium onto a titanium plate (100×100×0.4 mm, L×W×T for both electrodes). The electronic wastewaters used in this study were highly acidic (mainly composed of sulfuric and nitric acids, respectively) and contained a considerable amount of copper. The metals contained in the sulfuric acid wastewater were 92.95% of copper, 2.89% of iron, 1.19% of lead, and 2.97% of other trace metals and those in the nitric acid wastewater were 49.87% of aluminum, 45.97% of copper, and 4.16% of other trace metals. Inductively coupled plasma-optical emission spectroscopy was used to determine the recovery rate and purity of copper during electrolysis. Recovery rate of copper from sulfuric acid wastewater and its purity were 99.98% and 99.47%, respectively. Recovered copper was obtained in the form of thin foil at the high recovery rate. Furthermore, it was found that the recovery rate of copper from the sulfuric acid wastewater can be effectively enhanced by optimizing reaction run time, current density, and chemical additives. On the contrary, copper in nitric acid wastewater was not recovered by electrolysis. Instead, a precipitation method was employed for the recovery, and 86.54% of recovery rate was achieved as a copper hydroxide form. This copper can be recovered by dissolving into sulfuric acid wastewater followed by electrolysis process. Voltage and temperature did not change significantly, and the pH was maintained at the low level due to the H+ formation in the electrolysis process. The results of this study will be useful for the development of a process that efficiently recovers high purity copper from waste acids and wastewaters of plating process.

APPLICATION OF COLD SPRAY COATING TECHNIQUE TO AN UNDERGROUND DISPOSAL COPPER CANISTER AND ITS CORROSION PROPERTIES

Lee, Min-Soo,Choi, Heui-Joo,Choi, Jong-Won,Kim, Hyung-Jun Korean Nuclear Society 2011 Nuclear Engineering and Technology Vol.43 No.6

A cold spray coating (CSC) of copper was studied for its application to a high-level radioactive waste (HLW) disposal canister. Several copper coatings of 10 mm thick were fabricated using two kinds of copper powders with different oxygen contents, and SS 304 and nodular cast iron were used as their base metal substrates. The fabricated CSC coppers showed a high tensile strength but were brittle in comparison with conventional non-coating copper, hereinafter defined to as "commercial copper". The corrosion behavior of CSC coppers was evaluated by comparison with commercial coppers, such as extruded and forged coppers. The polarization test results showed that the corrosion potential of the CSC coppers was closely related to its purity; low-purity (i.e., high oxygen content) copper exhibited a lower corrosion potential, and high-purity copper exhibited a relatively high corrosion potential. The corrosion rate converted from the measured corrosion current was not, however, dependent on its purity: CSC copper showed a little higher rate than that of commercial copper. Immersion tests in aqueous HCl solution showed that CSC coppers were more susceptible to corrosion, i.e., they had a higher corrosion rate. However, the difference was not significant between commercial copper and high-purity CSC copper. The decrease of corrosion was observed in a humid air test presumably due to the formation of a protective passive film. In conclusion, the results of this study indicate that CSC application of copper could be a useful option for fabricating a copper HLW disposal canister.

17~18세기 대일銅무역과 정부의 주전사업

김영록 부경역사연구소 2018 지역과 역사 Vol.- No.43

In 1678, Joseon started to mint the new copper coin, Sangpyeong Tongbo (常平通寶). Coin production was one of the most important elements in the economic policy of Joseon government The essential prerequisite of coin was to secure a reliable source of raw materials. Since Joseon did not have sufficient copper reserves, the government had no choice but to rely on exclusively its import from Japan. The Japanese copper was introduced not only through public trade at Waegwan by which Joseon could procure a certain amount of copper, but also through the open market trade in which the government authorities bought Japanese copper by trade. In the later seventeenth century, the expansion of the open market trade at Waegwan resulted in the massive trade amount of copper. However, from 1698 to 1707, there was a rapid drop in trade off because of government control over copper. Even though Joseon government removed the control, Japanese government started to severely restrict the amount of copper exported to Joseon. In order to secure copper to make coins, Joseon tried to exploit the network of intermediary trade between Qing and Japan. There was a variety of obstacles to procure copper: limited trade volume, constant upheaval in trade condition, an advance on copper and failure of opening up copper mines. To tide over these difficulties, the government tried to restrict the domestic distribution of copper by controlling private transactions of copper with various means, including Gunggakgyebyuntongjeolmok (『弓角契變通節目』) of 1782. Under this condition, copper was to be procured preferentially to government authorities. Because of increasing demand of coin, Joseon government had to overcome a lack of raw materials to make more coin, which resulted in concentrating copper on the government authorities by restrict its trade and distribution. 1678년(숙종 4) 조선은 常平通寶를 발행하였다. 동전의 발행은 조선 정부의 경제정책에서 가장 중요한 요소 중 하나로 정부의 최대 관심사였다. 호조와 군문 등의 국가기관은 ‘各司自辦’의 원칙 아래 재정확보책의 일환으로 주전을 실시했다. 주전사업에서 선행되어야 할 조건은 무엇보다 원료의 안정적인 확보였다. 주전의 주원료인 銅은 국내 생산량이 미미하여 일본으로부터의 수입에 거의 전적으로 의존할 수밖에 없는 실정이었다. 일본의 銅은 17세기 초 대일무역이 재개되면서 왜관의 공무역과 개시무역으로 국내에 유입되었다. 조선은 공무역으로 매년 일정 수량의 동을 확보할 수 있었다. 개시무역에서는 군문을 위시한 각 국가기관이 차인을 파견하는 등 직접 무역에 개입함으로써 동을 무역하였다. 17세기 후반, 주전사업의 이익 실현을 위한 관과 민에 의한 경쟁적인 무역 거래로 왜관 개시무역의 규모가 더욱 확대되면서 1697년에는 동의 개시무역 거래량이 1,436,000근에 달할 정도였다. 하지만 18세기에 접어들어 일본의 동 통제책이 강화되면서 연간 10만 근의 수출한도액이 정해지게 되었고 조선에 수입되는 동의 수량은 한정되었다. 이에 주전원료를 확보하기 위한 조선의 환경은 더욱 긴박되어 갔다. 각 국가기관은 실질적인 주전사업이 시행하지 않음에도 불구하고 청·일간 중계무역망을 이용하여 은-청 물품[白絲 등]-동의 교환구조로 동을 확보하였으며, 이후 중계무역이 부진하자 은-인삼-동의 교환구조를 통해 동을 확보하였다. 이 과정에서 다량의 비축은이 활용되었고, 기관 간의 재원 상호대부도 활발했다. 지속적인 주전사업의 결과, 동은 은과 함께 각 국가기관의 주요 비축 재원으로 위치를 점하면서 각 기관의 재정확보책도 변화한 것으로 보인다. 각 국가기관이 동을 확보하는 과정은 장애 요소가 많았다. 동의 한정된 교역량, 무역환경의 잦은 변화, 동 가격의 상승, 국내 동광 개발의 부진 등은 지속적이고도 안정적인 주전사업의 전개를 방해하였다. 결국 동의 한정된 유통량, 높은 국외의존도에 의해 결국 정부는 동의 국내 유통망을 제한하는 정책을 추진해나갔다. 주전사업을 실시할 때에는 대일무역 동의 사적 거래를 제한함으로써 이를 확보하는 방안이었다. 1782년(정조 6)에 『弓角契變通節目』이 제정되면서 공무역 동은 호조에서 주관하였다. 이를 배경으로 1788년(정조 12) ‘연례주전제’가 실시되었다. 일정량의 공무역 동 외에도 주전물력을 충당하기 위해 동의 지속적이고도 안정적인 확보가 더욱 중요해졌다. 그 결과 정부는 대일무역 동의 국내 거래를 장악하기 위해 사적 거래에 대한 통제를 더욱 강화해나갔으며, 이는 절목의 제정으로 이어졌다. 주전사업이 시행될 때에는 훈도·별차와 都中은 절목에 따라 주원료인 동을 국가기관에 우선적으로 조달해야 했다. 동전의 수요가 지속적으로 증가하는 경향 속에서, 조선 정부는 동전의 안정적인 유통을 위해 주전사업의 원료난을 극복해야 했다. 이는 곧 동의 무역과 유통을 제한하는 정책으로 이어졌으며 더욱 강화되어 가는 추세였다. 이를 통해 정부는 주전 원료인 동을 국가기관에 집중시키고자 했다.

로우스틸 마찰재의 마찰 및 마모특성에 미치는 구리계 재료의 영향

정광기,이상우,권성욱,최성우,이희옥 한국트라이볼로지학회 2020 한국윤활학회지(윤활학회지) Vol.36 No.4

In this study, we investigated the effects of copper and copper-alloy on the frictional and wear properties of low-steel friction material. The proportions of copper and copper-alloy in the brake friction materials used in passenger cars are very high (approximately 5-20% weight), and these materials have significant effects on friction and wear characteristics. In this study, the effects of cupric ingredients, such as the copper fiber and brass fiber, are investigated using the friction materials based on commercial formulations. After the copper and brass fibers from the same formulation were removed, the frictional and wear characteristics were evaluated to determine the influence of the copper and copper-alloy. We evaluated the frictional and wear characteristics by simulating various braking conditions using a 1/5 scale dynamometer. The results show that the friction material containing copper and brass fibers have excellent frictional stability and a low wear rate compared to the friction material that does not contain copper and brass fibers. These results are attributed to the excellent ductility, moderate melting point, high strength, and excellent thermal conductivity of copper and copper-alloy. We analyzed the surfaces of the friction materials before and after the performing the friction tests using a scanning electron microscope-energy dispersive X-ray spectroscope, confocal microscope, and roughness tester to verify the frictional behavior of copper and copper-alloy. In future studies, it will be applied to the development of copper-free friction materials based on the results of this study.