An investigation into the recovery of oxide copper from a complex copper ore using sulphidisation technique and hydroxamate and potassium amyl xanthate collectors

Ahad Zare,Asghar Azizi,Mohammad Karamoozian 한국자원공학회 2020 Geosystem engineering Vol.23 No.1

This study was aimed to increase the floatability of oxide copper from a complex copper sample. For this purpose, sulphidisation processes such as slug and controlled potential sulphidisation (CPS) and hydroxamate and potassium amyl xanthate (Z6) collectors were utilized and their results were compared with real conditions. The results indicated that about 9.46% of the recovery of oxide copper increased using 300g/t ammonium sulphide in the first step, and reached to 77.12%. Also, in this case, the recovery of sulphide copper was significantly improved. In addition, the findings demonstrated that applying 10 g/t of potassium octyl hydroxamate anionic collector, the recovery of oxide copper reached to 74.47% without any negative effect on the recovery of sulphide copper. Meanwhile, the simultaneous use of Z11 and Z6 as collector caused to increase about 3.63% of the recovery of oxide copper (71.29%). It was also found that the highest recovery of oxide copper could be obtained using CPS method and in this case, 10.34% of the oxide copper and 4.48% of the total copper improved and also the dosage of (NH4)2S decreased.

Copper oxide - reduced graphene oxide core - shell structure photosensor

( Hanum Abdullah ),오준학 한국공업화학회 2015 한국공업화학회 연구논문 초록집 Vol.2015 No.0

Copper oxide (CuO) is one of the most important semiconductor due to its non - toxicity as well as abundance in nature. It is widely used in optoelectronics owing to its photoconductive properties. This project focuses on improving the light sensing properties of copper oxide. Copper oxide was incorporated with graphene - derivatives in the form of core - shell NW. With band gap of about 1.4eV, CuO capable to detect broad range of light starting from UV to NIR. These 2 materials, copper oxide and graphene were chosen not only for its intrinsic qualities, but also for its environment - friendly values. Only ‘green’ methods were utilized starting from synthesizing the copper oxide NW until the fabrication of the single NW device.

혼합 하중하에서의 고분자/거친금속 계면의 파손경로

이호영,김성룡,Lee Ho-Young,Kim Sung-Ryong 한국재료학회 2004 한국재료학회지 Vol.14 No.5

Copper-based leadframe sheets were oxidized in two kinds of hot alkaline solutions to form brown-oxide or black-oxide layer on the surface. The oxide coated leadframe sheets were molded with epoxy molding compound (EMC). After post mold curing, the oxide-coated EMC-leadframe joints were machined to form sandwiched Brazil-nut (SBN) specimens. The SBN specimens were used to measure the fracture toughness of the EMC/leadframe interfaces under mixed-mode (mode I + mode II) loading conditions. Fracture surfaces were analyzed by various equipment to investigate failure path. The results revealed that the failure paths were strongly dependent on the oxide type. In case of brown oxide, hackle-type failure was observed and failure path lay near the EMC/CuO interface with a little inclining to CuO at all case. On the other hand, in case of black oxide, quite different failure path was observed with respect to the distance from the tip of pre-crack and phase angle. Different failures occurred with oxide type is presumed to be due to the difference in microstructure of the oxides.

Association between Copper–Zinc Ratio in Hair and Neutrophil–Lymphocyte Ratio within the Context of a Normal White Blood Cell Count among Overweight or Obese Korean Individuals: A Pilot Study

Jung Sun Young,Shim Hyo Young,이영재,Park Byoungjin 대한가정의학회 2021 Korean Journal of Family Medicine Vol.42 No.3

Background: Obesity is considered a state of enhanced oxidative stress as well as chronic and low-grade inflammation. The copper–zinc ratio in obese individuals has been reported to reflect systemic oxidative stress and inflammatory status. We investigated whether the neutrophil–lymphocyte ratio is related to the copper–zinc ratio in hair, within the context of a normal white blood cell count among overweight or obese Korean individuals. Methods: We included 56 participants aged older than 20 years who voluntarily sought weight reduction treatment and met the inclusion criterion of body mass index of 23 kg/m2 or greater. Intra-abdominal visceral adipose tissue was measured by computed tomography imaging, while the copper and zinc levels were measured by hair mineral analysis. Using multiple linear regression analysis, we examined the associations between the neutrophil–lymphocyte ratio and the copper–zinc ratio. Results: The mean age, body mass index, and visceral adipose tissue were 46.0±10.5 years, 29.0±4.1 kg/cm2, and 142.9±68.8 cm2, respectively. Pearson’s correlation analysis revealed the association of the neutrophil–lymphocyte ratio with copper level (r=0.475, P<0.001) and copper–zinc ratio (r=0.494, P<0.001). After adjusting for confounding variables, we found the neutrophil–lymphocyte ratio was significantly associated with the level of copper and the copper–zinc ratio in hair (regression coefficient: 0.055±0.015; P<0.001 and regression coefficient: 0.761±0.185; P<0.001, respectively). Conclusion: A higher copper–zinc ratio in hair is positively and independently associated with the neutrophil–lymphocyte ratio. Thus, a high hair copper–zinc ratio could be a useful parameter for oxidative burden of individuals predisposed to obesity-related comorbidity.

Effect of Carboxylic Acid on Sintering of Inkjet-Printed Copper Nanoparticulate Films

Woo, Kyoohee,Kim, Youngwoo,Lee, Byungyoon,Kim, Jonghee,Moon, Jooho American Chemical Society 2011 ACS APPLIED MATERIALS & INTERFACES Vol.3 No.7

<P>The reduction effect of various carboxylic acids on inkjet-printed copper film was investigated. Carboxylic acids were exposed to the film by nitrogen gas that was bubbled through the liquid acids during the annealing process. It was observed that in the case of saturated monocarboxylic acid (formic, acetic, propionic, butyric), the acids with shorter hydrocarbon chains perform better in reducing the surface copper oxides in the printed copper conductive film. The printed films exposed to formic acid vapor exhibited the lowest resistivity (3.10 and 2.30 μΩ cm when annealed at 200 and 250 °C, respectively). In addition, the oxalic acid more effectively reduces copper oxide than formic acid and its usage can shorten the annealing time for highly conductive printed copper film. This reductive annealing process allows fabrication of copper patterns with low resistivity, (3.82 μΩ cm annealed at 250 °C) comparable to the resistivity of bulk copper.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/aamick/2011/aamick.2011.3.issue-7/am2002907/production/images/medium/am-2011-002907_0004.gif'></P>

Sea-urchin-like mesoporous copper-manganese oxide catalysts: Influence of copper on benzene oxidation

Hyunji Lee,Jae Hwan Yang,Jeong Hyun You,Been Young Yoon 한국공업화학회 2020 Journal of Industrial and Engineering Chemistry Vol.89 No.-

Mesoporous copper manganese oxides were prepared via a simple method to be used for the catalyticoxidation of benzene emitted from industrial activities. Morphological characterization revealed that theprimary particles of the as-synthesized catalysts were nanorods that aggregated with each other to formsea-urchin like structures. Compared with the manganese oxide based catalyst, copper manganeseoxides exhibited better performances for benzene oxidation, achieving the best benzene conversion rateof 90% at around 219 C, which is 23 C lower than that for the catalyst without copper. The benefit ofcopper addition exists because the addition of copper in the manganese oxide causes desorption of latticeoxygen, increasing concentrations of oxygen defects on the catalyst surfaces. Furthermore, the addition ofcopper was found to contribute to the increase in the specific surface area by reducing the sizes of thenanorods and sea-urchin structures. Finally, the influential factors for catalytic oxidation were oxygenvacancies and the oxidation state of metals.

Virgin olive oil blended polyurethane micro/nanofibers ornamented with copper oxide nanocrystals for biomedical applications

Amna, Touseef,Hassan, M Shamshi,Yang, Jieun,Khil, Myung-Seob,Song, Ki-Duk,Oh, Jae-Don,Hwang, Inho Dove Medical Press 2014 INTERNATIONAL JOURNAL OF NANOMEDICINE Vol.9 No.-

<P>Recently, substantial interest has been generated in using electrospun biomimetic nanofibers of hybrids, particularly organic/inorganic, to engineer different tissues. The present work, for the first time, introduced a unique natural and synthetic hybrid micronanofiber wound dressing, composed of virgin olive oil/copper oxide nanocrystals and polyurethane (PU), developed via facile electrospinning. The as-spun organic/inorganic hybrid micronanofibers were characterized by scanning electron microscopy (SEM), energy dispersive X-ray analysis, X-ray diffraction, electron probe microanalysis, and transmission electron microscopy. The interaction of cells with scaffold was studied by culturing NIH 3T3 fibroblasts on an as-spun hybrid micronanofibrous mat, and viability, proliferation, and growth were assessed. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay results and SEM observation showed that the hybrid micronanofibrous scaffold was noncytotoxic to fibroblast cell culture and was found to benefit cell attachment and proliferation. Hence our results suggest the potential utilization of as-spun micronanoscaffolds for tissue engineering. Copper oxide–olive oil/PU wound dressing may exert its positive beneficial effects at every stage during wound-healing progression, and these micronanofibers may serve diverse biomedical applications, such as tissue regeneration, damaged skin treatment, wound healing applications, etc. Conclusively, the fabricated olive oil–copper oxide/PU micronanofibers combine the benefits of virgin olive oil and copper oxide, and therefore hold great promise for biomedical applications in the near future.</P>

알코올 섭취와 흡연이 혈청 구리, 아연과 Nitric Oxide에 미치는 영향

홍연표,최병선,박정덕,장임원,Hong, Yeon-Pyo,Choi, Byung-Sun,Park, Jung-Duck,Chang, Im-Won 대한예방의학회 1998 예방의학회지 Vol.31 No.2

To investigate the change of nitric oxide(NO), copper, and zinc in serum on smoking and alcohol ingestion in young adults, this study was performed in a cross-sectional study in 127 healthy men in Korea who had HBsAg(-), HCVAb(-), and no symptomatic liver, heart, gastrointestinal, chronic diseases, and inflammatory sign(lower than 10,000 white blood cell count in CBC). At the men's entry into the study, blood samples were drawn from each subject and immediately centrifuged for analysis of NO, copper, and zinc. Each man completed a questionnaire that provided information on smoking, alcohol intake and present and past medical history NO was analyzed by HPLC(Green et al., 1982), copper and zinc by atomic absorption spectrophotometer with air-acetylene flame and total cholesterol(TC) by Spectrum EPX. Smoking(number of cigarettes per day and pack-year) and alcohol intake was grouped fertile. Copper was adjusted for age and zinc and for age and TC. NO, copper, and zinc on smoking and alcohol ingestion were analyzed in general linear models, respectively. NO, copper and zinc in serum did not show statistical differences between non-smoking and high-smoking group and no-alcohol intake and high-alcohol intake group. This study suggested that copper, zinc, and NO was not. good biological marker for early effect by smoking and alcohol intake in young adults. However, selection bias should be considered in evaluation of this result. A large prospective study will be needed in advance on usefulness of copper, zinc, and NO as a marker for risk factors and early change of atherosclerosis.

Fabrication of Hydrophobic Surfaces using Copper Electrodeposition and Oxidation

Kwon, Min Ho,Jee, Won Young,Chu, Chong Nam Korean Society for Precision Engineering 2015 International Journal of Precision Engineering and Vol.16 No.5

The fabrication process of metallic hydrophobic surfaces was investigated using copper electrodeposition and oxidation. Hierarchical structures have well known advantages for producing super-hydrophobic surfaces. A micro-pillar array with a hierarchical structure of copper was fabricated through a sequential process of laser ablation followed by electrodeposition. Heat oxidation enhanced the hydrophobicity of both flat and micro-structured copper surfaces. Electrodeposition at higher current density gave a hierarchical structure with low surface energy, resulting from the presence of copper oxide. Fabricated surfaces with a depth of more than 100 micrometers display super-hydrophobicity. The effects of copper oxide and hierarchical structure were confirmed by an oxidation test of the fabricated structures, because the thickness of copper oxide was undetectable by XRD and XPS.

Fabrication of Hydrophobic Surfaces using Copper Electrodeposition and Oxidation

권민호,지원영,주종남 한국정밀공학회 2015 International Journal of Precision Engineering and Vol. No.

The fabrication process of metallic hydrophobic surfaces was investigated using copper electrodeposition and oxidation. Hierarchical structures have well known advantages for producing super-hydrophobic surfaces. A micro-pillar array with a hierarchical structure of copper was fabricated through a sequential process of laser ablation followed by electrodeposition. Heat oxidation enhanced the hydrophobicity of both flat and micro-structured copper surfaces. Electrodeposition at higher current density gave a hierarchical structure with low surface energy, resulting from the presence of copper oxide. Fabricated surfaces with a depth of more than 100 micrometers display super-hydrophobicity. The effects of copper oxide and hierarchical structure were confirmed by an oxidation test of the fabricated structures, because the thickness of copper oxide was undetectable by XRD and XPS.