• Resources Recycling
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• v.9 no.1
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• pp.70-75
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• 2000

The sand particle was coated with $Fe_3O_4$ and then $Fe_2O_3$ that adsorption capacity was more excellent than $Fe_3O_4$ was mostly found in 2nd step for preparation of iron-oxide-coated sand (IOCS). The copper removal rate was 74.9 percent by adding 30 gram per liter iron-oxide-coated sand from the solution with 5 mg/l Cu in 20 minute. Breakthrough time occurred in 23 hours and adsorption capacity 0.87$\cdot$Cu/g$\cdot$IOCS in case of breakthrough copper concentration was 1.0 mg/l in the continuous test.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.326-326
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• 1994

중금속이 양서류의 발생에 미치는 영향을 알아보기 위해 Xenopus embryo 2 할구기부터 카드뮴, 수은, 납. 구리, 아연 등을 여러 농도로 지속적으로 처리한 후 치사율과 이상 발생율을 조사하였다 그 결과 수은, 카드뮴. 구리, 납. 아연의 순으로 독성이 강함을 알 수 있다. 중금속 중 카드뮴 처리시 나타나는 현상으로는 창자, 눈, 체축. 지느러미, 십장 등의 이상과 수포 등을 들 수 있다. FETAX (frog Embryo Teratogenesis Assay : Xenopus)의 분석 결과 LC$_{100}$ 은 1.5 ppm, EC$_{100}$은 1PPm 이었고 기형 유발지수(TI)가 2. 8 인 점으로 보아 카드뮴을 Xenopus embryo에 있어서 기형유발원으로 분류할 수 있다.

• Journal of the Korean institute of surface engineering
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• v.16 no.4
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• pp.160-172
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• 1983

티오요소류, 폴리에테르류, 염료와 같은 유기화합물이 첨가된 황산동 전기도금욕에서 석출된 구리의 광택, 평활력효과를 무첨가욕과 기존 광택제가 첨가된 도금욕에서와 각각 비교하여 이들 유기첨가제가 구리의 석출상태와 음극분극에 미치는 영향을 Hull cell 실험과 현미경관찰, 전기화학적 측정방법에 의해 고찰하였다. 황산동 전기도금욕에서 thiourea, 2-mercapto-2-imidazoline, 1-acetyl-2-thiourea와 같은 유기 황화합물은 비교적 고전류 밀도 범위에서 결정성장이 억제되고 입자가 미세한 구리석출을 일으켜 양호한 광택효과와 평활력을 가져오나, 특히 저전류밀도에서는 해로운 줄무늬가 발생한다는 점에서 많은 개선의 여지가 필요하다. 그러나 이들 유기 황화합물에 1,3-dioxolane polymer와 소량의 염소 이온을 혼합 첨가할 것 같으며 넓은 전류밀도 범위에서 양호한 광택과 평활력이 있는 동석출을 얻을 수 있었다.

• Resources Recycling
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• v.26 no.4
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• pp.95-100
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• 2017

In this study, $Fe_2O_3$ was added as a flux to decrease melting temperature and refine during melting of Cu powder from scraped surface of the waste PCB (printed circuit board). The effect of $Fe_2O_3$ ratio to Cu powder and temperature on the recovery of Cu and content of impurities were investigated. It was found that the recovery of Cu was increased with increasing addition ratio of $Fe_2O_3$ and reaction temperature. The contents of O, Si and Fe in Cu phase were also decreased with increasing addition ratio of $Fe_2O_3$ and temperature. The formation of fayalite ($2FeO{\cdot}SiO_2$) and iron oxides phases in the slag was confirmed by XRD analysis after reaction with $Fe_2O_3$. Therefore, it was considered that the decrease of melting temperature and viscosity of slag by formation of fayalite slag contributed remarkably to the Cu recovery.

• Journal of Conservation Science
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• v.31 no.3
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• pp.193-214
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• 2015

The green pigments of shamanic paintings (83 items) in the 19~20th century were analyzed with X-ray fluorescent spectrometer(XRF), scanning electron microscopy (SEM) and fourier transform infrared spectroscopy (ATR-FTIR). In 60 items, copper and arsenic were detected in green pigments of the paintings by XRF spectra. Cu $K{\alpha}$/As $K{\beta}$ (peak intensity ratio of copper and arsenic) of shamanic paintings of Bokgaedang (shrine), solemn paintings (romance of three kingdoms) of Donggwanwangmyo and unknown enshrined place were 5.93~12.04 and higher compared to 5.67-6.26 of standard emerald greens and 4.01~7.89 of remaining shamanic paintings. The SEM images of crystal forms of copper-arsenic green pigments were various. Crystal forms were divided into oval and round spherulite with intersecting plate crystals and spherulite with agglomerate plate crystals. The crystals of the latter were found in shamanic paintings of Bokgaedang (shrine), solemn paintings (romance of three kingdoms) of Donggwanwangmyo and unknown enshrined place and the former were found in the rest of shamanic paintings. Copper-arsenic green pigments of shamanic paintings were identified as Scheele's green from shamanic paintings of Bokgaedang (shrine) and romance of three kingdoms. Emerald green from the rest of shamanic paintings by ATR-FTIR. From analytical results, it is confirmed that Scheele's green of shamanic paintings of Bokgaedang and romance of three kingdoms was used in the 1850s~1870s and emerald green had been widely used from late 19th century to 1970 in the rest of shamanic paintings.

• Journal of Preventive Medicine and Public Health
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• v.23 no.3 s.31
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• pp.296-308
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• 1990

The relationship between copper and mercury contents in the scalp hair and chronic schizophrenia was investigated. The samples of scalp hair were collected from 80 male chronic schizophrenic patients at the age from 20 to 29, who were hospitalized in the National Psychiatric Hospital in Seoul. As the control group, 69 males were collected from general population. Hair samples were taken from the napes and the Minnesota Multiple Personality Inventory (MMPI) was performed also. The copper and mercury contents were determined by an atomic absorption spectrophotometer. Significantly higher T-score of MMPI was seen in patients group for Hypochondriasis Scale (Hs), Depression Scale (D), Psychopathic Deviate Scale (Pd), Paranoia Scale (Pa), Psychasthenia Scale (Pt), Schizophrenia Scale (Sc) subscales than control group, and the frequency distribution by T-score was also significantly different between the patient and the control group for above scales. The content of copper in the hair of patient group was significantly lower than the control group. In the case of mercury, the mean value of patient group was significantly higher than control group. Between the value of copper and mercury, statistically significant negative correlation (r=-0.25) was found. When grouped by the T-score of MMPI, there was no difference of copper contents between T-score subgroup at all MMPI scale. But the mercury contents showed significant difference between T-score subgroup at Pt, Sc scale. When compared between the group of above 70 T-score and the group of less than 70, the mercury contents of Pa, Pt, Sc scale of above 70 T-score group were significantly higher than the group of less than 70. In other scales, the mercury content of the above 70 group were higher than the group of less than 70 except Mf scale, although there were no statistscally significances. In D, Pa, Sc scales, as the T-score of MMPI increased, the contents of mercury also increased. When divided into the patient group and the control group, the copper contents of the patient groups were significantly lower than the control group at each T-score scale in most MMPI scales. In the case of mercury, the value of patient group were significantly higher than the control group in the less than 44 scale of D, in the $60{\sim}69$ scale of Pd, in the $45{\sim}59$ scale of Mf, in the $60{\sim}69$ scale of Ma, in the less than 44 of Si. These results suggest that the effects of the deficiency of copper or high intake of mecury on schizophrenia and personality may be of possible value. Thus further studies are necessary to determine whether schizophrenia and personality formation would be attributed to copper deficiency or mercury intake.

• Korean Journal of Ecology and Environment
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• v.44 no.3
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• pp.272-279
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• 2011

Copper cyanide is a chemical produced in large quantities with 2,500 tonnes being produced in 2006. It is mainly used for electroplating copper, particularly alkali-Cu plate and brass plating. The purpose of this study is to reassess the physicochemical properties and environmental fate of copper cyanide based on reliable data and and to conduct an ecotoxicity test according to the OECD test guidelines as an initial environmental risk assessment (need to state where this was done). Metal containing inorganic substances are not subject to degradation, biodegradation or hydrolysis. Aquatic toxicity tests of copper cyanide were conducted according to OECD test guideline 201, 202 and 203 for green algae, daphnia, and fish, respectively. The following acute toxicity test results were obtained for aquatic species: 0.089 mg $L^{-1}$ (Algae, 72 Hr-$EC_{50}$); 0.21 mg $L^{-1}$ (flea, 48 Hr-$LC_{50}$); 0.62 mg $L^{-1}$ (Fish, 96 Hr-$ErC_{50}$). The chemical possesses properties indicating a hazard for the aquatic environment (acute toxicity in fish, daphnia and algae below 1.0 mg $L^{-1}$). As a result of this study, copper cyanide has become a candidate for detailed risk assessment. Countries that produce this chemical in significant quantities are recommended to perform specific assessments.

• The Korean Journal of Malacology
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• v.31 no.2
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• pp.151-158
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• 2015

This study was conducted to find out the changes of survival, respiration and organ structure of Tegillarca granosa exposed to copper (Cu). Experimental period was four weeks. Experimental groups were composed of one control condition and three copper exposure conditions (0.125, 0.250 and 0.500 mg/L). The results of the study confirmed that copper induces reduction of survival rate and respiration rate and histopathology of organ structure of the bivalve. In the copper concentration of 0.500 mg/L, mortality was 66.7% after Cu exposure of 4 weeks. Respiration rate was observed exposure groups lower than control decline by 18%. Histological analysis of organ system illustrated degeneration of epithelial layer and connective tissue layer of the mantle. Also, histological degenerations as epithelial atrophy and disappearance of lateral cilia are recognized in the gill and it was observed expansion of hemolymph sinus, disruption of epithelial layer, acidification of mucous and degeneration of muscle fiber bundles in the foot. In the digestive diverticulum, it was showed atrophy and destruction of basophilic cell and epithelial cell in the digestive tubules.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.1 no.1
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• pp.37-42
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• 2000

Copper thin films have been prepared by a metal organic chemical vapor deposition (MOCVD) technology on polyimide and TiN substrates. The Cu-MOCVD technology has advantages of the high deposition rate and the good step coverage compared with the conventional physical vapor deposition (PVD) technology in several industrial applications. The Cu films have been deposited with varying the experimental conditions of substrate temperatures and copper source vapor pressures. The films were annealed in a vacuum condition after the deposition, and the annealing effect on the electrical properties of the films was measured. The crystallinity and the microstructures of the films were observed by scanning electron microscopy (SEM), and the electrical resistivity was measured by 4-point probe. In the case of the Cu deposition on TiN substrate, the best electrical property of the films was measured for the samples prepared at 18$0^{\circ}C$. Very high deposition rate of the Cu film up to 250 nm/min was obtained on the polyimide substrate when the mixture of liquid and vapour precursor was used.

• Korean Journal of Heritage: History & Science
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• v.43 no.3
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• pp.102-121
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• 2010

Three bronze bells excavated from the Hoeamsa temple site were investigated for their microstructures and chemical compositions in an effort to understand the technology applied in fabrication, which may represent the related industry established in the early Joseon period. The result shows that the bells were cast from alloys of approximately 85% copper-8% tin-7% lead. The chemical analysis for ten trace elements shows that they were all kept below 0.3 weight %, suggesting that the alloys were made of relatively well-refined copper, tin and lead. The presence of sulfur and iron indicates that chalcopyrite or chalcocite may have been used in the smelting of copper. Evidence has been found that the bells were cast by pouring the liquid metal from the top of the sand molds that were set up in an upright position. No additional treatments, thermal or mechanical, other than a little grinding were applied upon the completion of casting. After the shaping process, a balancing plate was attached to the top of the bell using a steel connection ring. The connection assembly was then fixed to the main body by using molten bronze as a solder. The surface inscription was found carved using different techniques. The differences in the order of strokes and the calligraphic style indicate that the carving was carried out by more than one master. In the absence of documentary evidence on past bronze technology, the present bronze bells with known chronology, provenance and the main agent of production, prove to be a rare and valuable archaeological material for the understanding of the related technology in use in the early Joseon period.