• Asian-Australasian Journal of Animal Sciences
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• v.29 no.11
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• pp.1608-1615
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• 2016

This study was conducted to determine the solubility of copper (Cu) in two sources of copper(II) sulfate ($CuSO_4$) including monohydrate and pentahydrate and three sources of dicopper chloride trihydroxide (dCCTH) including ${\alpha}$-form (dCCTH-${\alpha}$), ${\beta}$-form (dCCTH-${\beta}$), and a mixture of ${\alpha}$- and ${\beta}$-form (dCCTH-${\alpha}{\beta}$) at different pH and a 3-step in vitro digestion assay for pigs. In Exp. 1, Cu sources were incubated in water-based buffers at pH 2.0, 3.0, 4.8, and 6.8 for 4 h using a shaking incubator at $39^{\circ}C$. The $CuSO_4$ sources were completely dissolved within 15 min except at pH 6.8. The solubility of Cu in dCCTH-${\alpha}$ was greater (p<0.05) than dCCTH-${\beta}$ but was not different from dCCTH-${\alpha}{\beta}$ during 3-h incubation at pH 2.0 and during 2-h incubation at pH 3.0. At pH 4.8, there were no significant differences in solubility of Cu in dCCTH sources. Copper in dCCTH sources were non-soluble at pH 6.8. In Exp. 2, the solubility of Cu was determined during the 3-step in vitro digestion assay for pigs. All sources of Cu were completely dissolved in step 1 which simulated digestion in the stomach. In Exp. 3, the solubility of Cu in experimental diets including a control diet and diets containing 250 mg/kg of additional Cu from five Cu sources was determined during the in vitro digestion assay. The solubility of Cu in diets containing additional Cu sources were greater (p<0.05) than the control diet in step 1. In conclusion, the solubility of Cu was influenced by pH of digesta but was not different among sources based on the in vitro digestion assay.

• Applied Biological Chemistry
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• v.46 no.1
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• pp.7-11
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• 2003

Cloning and expression of copper-binding peptide gene in E. coli was carried out to enhance the copper-chelation capacity. E. coli was transformed with pET vector containing the copper-binding region of potato polyphenol oxidase gene and polyhistidine-coding DNA, and the copper content of E. coli harboring each vector was measured. No increase in intracellular copper was observed in E. coli harboring PPOCBpET32 vector, which contains DNA for polyphenol oxidase copper-binding region. Intracellular copper content of E. coli harboring pE728a vector, which contains one hexahistidine unit DNA, was 2,500 ppm after culturing without kanamycin, whereas E. coli harboring pET-his vector, which contains nine hexahistidine unit DNAs was 3,200 ppm.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.26 no.3
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• pp.101-108
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• 2016

Each year, more than seven hundred thousand tons of copper slag are generated in Korea as a byproduct during the production of copper. Due to the large amount of copper slag produced, there has been increased interest in the use of copper slag as a construction material. To evaluate the potential of copper slag as a construction material, laboratory evaluations were conducted in this study, and three particle shapes and replacement rates of river sand were selected as experimental variables. Strength, air-void characteristics, and sulfuric acid resistance were the three properties evaluated to assess whether copper slag can be used as a construction material. Test results indicate that the gradation of copper slag has an effect on strength, and the maximum strength was achieved when 60 % of river sand was replaced with copper slag. In addition, when compared with ordinary Portland cement mortar, replacing river sand with copper slag reduced air void size and increased sulfuric acid resistance.

• Applied Chemistry for Engineering
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• v.10 no.5
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• pp.804-807
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• 1999

New copper complexes with a ligand, L(L=N,N'-cyclohexane bis(ferrocenylmethylene)amine) which was obtained from ferrocene carboxaldehyde and 1,2-diaminocyclohexane with a mole ratio of 2:1, were prepared and characterized. Those were adapted to asymmetric catalysis. The copper(II) complexes do not work in cyclopropanation of styrene and ethyl diazoacetate but copper(I) complex catalyzes. The Cu(I)LOTf (OTf=trifluorometanesulfonate) shows a good regioselectivity giving high trans to cis ratio of up to 80:20.

• Korean Journal of Animal Reproduction
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• v.12 no.2
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• pp.84-90
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• 1988

This study was done with mouse embryos to determine effects of the freezing media with or without 10% sucrose, and seeding methods (pincette, no seeding, liquid nitrogen gas phase and copper wire coiled straw) on embryo survival were determined using the FDA test. The summarized results are the following. 1. The FDA score found with copper wire coiled straw, no seeding, pincette and liquid nitrogen gas phase was 3.6, 3.6, 3.3 and 3.0, respectively. There were no significant differences. 2. The embryo score shows higher (P<0.05) survival rate using a freezing medium with sucrose than the one without it. Among the seeding procedure, better resutls are copper wire coiled straw and no seeded. 3. The results suggest that copper wire coiled seeding no seeding be as good as seeding when the mouse embryos were frozen in a liquid nitrogen container using both the freezing and dilution media containing 10% sucrose.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2006.11a
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• pp.64-65
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• 2006

The effects of garlic extracts, lactic acid bacteria, copper and selenium as cholesterol lowering material on productivity and content of egg cholesterol in layer were investigated. The layers were divided into seven treatment groups and fed commercial diet or experimental diets containing probiotics, garlic powder, selenium and copper for 6 weeks. There was no significant difference in egg production between groups. The content of egg yolk cholesterol by combination feeding of probiotics, garlic powder, selenium and copper were significantly reduced by 13.5-29.8% as compared to that of control. The levels of mRNA expression of HMG-CoA reductase were significantly decreased by dietary treatments.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1997.04a
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• pp.150-153
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• 1997

Langmuir-Blodgett(LB) technique is one of the ways of fabricating organic ultra-thin films. It is well known that It has the advantage to control the alignment and orientation of the molecules in the films. Metallo-phthalocyanines(MPcs) are sensitive to electron affinitive toxic gaseous molecules, such as NO$_2$, NO, SO$_2$. MPcs are thermal, optical, mechanical, chemical stable. Therefore, it is interesting to prepare phthalocyanine LB films containing copper as a chemical sensor for NO$_2$ and SO$_2$ gas and test their sensitivity to these toxic gases. In this study, thin films of Octa-dodecylosy copper-phthalocyanine were prepared by LB technique. $\pi$-A isotherm, transfer ratio, UV-VIS. spectroscopy of these films were investigated. Also current-voltage(I-V) characteristics of these was auto investigated.

• Resources Recycling
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• v.23 no.3
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• pp.30-36
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• 2014

A large amount of waste copper slag containing about 35 ~ 45% iron has been generated and discarded every year from pyrometallurgical processes for producing copper from copper concentrate. Thus, recovery of iron from the waste copper slag is of great interest for comprehensive use of mineral resource and reduction of environment problems. In this study, a physico-chemical separation process for upgrading iron from the waste copper slag discharged as an industrial waste has been developed. The process first crushes the waste copper slag below 1 mm (first crushing step), followed by carbon reduction at $1225^{\circ}C$ for 90 min (carbon reduction step). And then, resulting material is again crushed to $-104{\mu}m$ (second crushing step), followed by wet magnetic separation (wet magnetic separation step). Using the developed process, a magnetic product containing more than 66 wt.% iron was obtained from the magnetic separation under a magnetic field strength of 0.2 T for the waste copper slag treated by the reduction reaction. At the same conditions, the percentage recovery of iron was over 72%. The iron rich magnetic product obtained should be used as a iron resource for making pig iron.

• KSBB Journal
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• v.10 no.5
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• pp.475-481
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• 1995

The effect of metallothionein expression on the metal resistance and removal by recombinant Saccharomyces cerevisiae containing the plasmid pJW9 was investigated. The recombinant strain S. cerevisiae BZ-pJ was constructed by transforming the host strain S. cerevisiae BZ3l-1-7Ba with the gene coding for a metal-binding protein, metallothionein. Introduction of the MT gene yielded an increase in the minimum inhibitory concentration (MIC) of copper more than three times compared with the host strain. The minimum inhibitory concentrations of $Cr^{2+}, Znr^{2+} and Pb^{2+}, $ were not different for the two strains. The recombinant yeast grown in a medium containing 8mM CuSO4 was able to remove copper with a capacity of 18.9mg $Cu^{2+}$/g dry cell. In a mixture of copper and zinc, the presence of copper relieved the toxic effects caused by zinc, resulting in an enhancement of the final cell density and the specific growth rate of the recombinant yeast. The capability to remove copper by the recombinant yeast was linearly proportional to the copper concentrations in the medium. The efficiency of copper removal was rather constant regardless of the initial copper concentrations. The specific removal of zinc was dependent on the zinc concentrations in media, though, and such dependence was not so pronounced as the concentration of copper.

• Membrane and Water Treatment
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• v.9 no.6
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• pp.481-487
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• 2018

Membrane clogging or fouling of the membrane caused by organic, inorganic, and biological on the surface is one of the main obstacles to achieve high flux over a long period of the membrane filtration process. So researchers have been many attempts to reduce membrane fouling and found that there is a close relationship between membrane surface hydrophilicity and membrane fouling, such that the same conditions, a greater hydrophilicity were less prone to fouling. Nanotechnology in the past decade is provided numerous opportunities to examine the effects of metal nanoparticles on the both hydrophilic and antibacterial properties of the membrane. In the present study the improvement of hydrophilic and antimicrobial properties of the membrane was evaluated by adding nanoparticles of titanium dioxide and copper oxide. For this purpose, 4% copper oxide and titanium dioxide nanoparticles with a ratio of 0, 30, 50, and 70% of copper oxide added to the polymeric membrane and compare to the pure polymeric membrane. Comparison experiments were performed on E. coli PTCC1998 in two ways disc and tube and also to evaluate membrane hydrophilic by measuring the contact angle and diameter of pores and analysis point SEM has been made. The results show that the membrane-containing nanoparticle has antibacterial properties and its impact by increasing the percentage of copper oxide nanoparticles increases.