• Journal of the Korean Ceramic Society
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• v.45 no.6
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• pp.320-323
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• 2008

The preparation of $Zn_xMn_{1-x}Fe_2O_4$ nanoparticles in an Igepal CO-520-cyclohexane water reverse micelle solution has been studied. The transmission electron microscopy and X-ray diffraction pattern analyses revealed the resulting particles to be $Zn_xMn_{1-x}Fe_2O_4$. The average size and distribution of the synthesized particles calcined at $500^{\circ}C$ for 5 h were in the range of 10 to 20 nm and broad, respectively. The phase of the synthesized particles was crystalline, the magnetic behavior of the synthesized particles was ferromagnetic. The effect of the synthesis parameters, such as the molar ratio of water to surfactant and calcination temperature, is discussed.

• Resources Recycling
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• v.6 no.1
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• pp.35-39
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• 1997

This study was carried out to find the existing forms of chlorlnc in EM dust and to understand the valaliliratian behavior and the removal of chlorine from EAF dust with lemperalure and heating almosphere The chemical compositions of dust A are 27.3%Fe. 21.8%3Zn, 3 15%Pb, 3 51%C1 and that of dust B BE 33.92%Fe, 15.94%Zn, 2.73% Pb, 3.98%Cl. The XRD analysis and water leaching test shows that chlorlne in EM dust exist mainly as NaCI, KCI, Pb (0H)Cl. Above 99% of chlorine was volatilized when dust was hentcd in alr atmosphere at 1100$^{\circ}$C h r 1 hour and that was 96% when heated in reduction atmosnherc at 1100$^{\circ}$C for 1 hour.

• Asian Journal of Turfgrass Science
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• v.10 no.4
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• pp.297-304
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• 1996

The investigation was performed to reveal the removal rate of metal constituents of litters in a Phragmites communis Miseanthus sacchariflorus, Typha angastata and Seirpas tabernaemontani grasslands in the lake Paldangho. The removal rates of metal constituents are determined by the mathematical models. The removal rates and time required to decay up to a percentage of each metal constituent were calculated using these model. The removal rates of Cu, Fe and Zn were 0.61, 0.58 and 0.79 in Phragmites communis 0.39, 0.47 and 0.68 in Miseanthus saccharflorus; 0.26, 0.09 and 0.23 in Typha angustata: 0.56, 0.27 and 0.67 in Seirpus tabernaemontani respectively. The periods required to reach half time to the stedy state of the removal and accumulation for Cu, Fe and Zn were 1,13,1.19 and 0.79 years in Phragmites communis; 1.79, 1.49 and 1.02 years in Miscanthus sacchariflorus; 2.70, 7.43 and 2.96 years in Typha angustata ; 1.23, 2.58 and 1.04 years in Scirqus tabernaemontani, re-spectively. Key words: Phragmites communis, Miscanthus sacchariflorus, Typha angustata and Scirpus tabernaemontani, lake Paldangho, Removal rate, Cupper, Iron, Zinc.

• Journal of Animal Science and Technology
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• v.57 no.2
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• pp.6.1-6.5
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• 2015

The objectives of this study were to study the effects of different levels of dietary copper on organ indexes, tissular Cu, Zn and Fe deposition and fur quality of mink in the growing-furring periods. One hundred and five standard dark male mink were randomly assigned to seven groups with the following dietary treatments: basal diet with no supplemental Cu (Control); basal diet supplemented with either 6, 12, 24, 48, 96 and 192 mg/kg Cu from copper sulphate, respectively. The colour intensity scores displayed a linear trend (P = 0.057). The spleen Cu concentrations responded in a linear (P < 0.05) fashion with increasing level of Cu, but copper supplementation did not affect speen concentrations of Fe or Zn. Supplemental dose of Cu linearly increased (P < 0.05) liver Cu and Fe concentrations but did not alter (P > 0.10) liver Zn. Our results indicate that Cu plays an important role in the pigmentation in growing-furring mink, and supplemental dietary Cu in growing-furring mink improve hair colour, and copper has limited effects on liver mineral deposition.

• Advances in nano research
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• v.5 no.2
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• pp.171-178
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• 2017

Superparamagnetic Zinc ferrite submicropheres are firstly synthesized via a one-pot solvothermal approach at $200-215^{\circ}C$ for 4-8 hours. $ZnCl_2$, $FeCl_3$ and NaAc are used as precursors with ethylene glycol solvent. The X-ray diffraction (XRD) data indicate that $ZnFe_2O_4$ nanoparticles with the grain size around $15{\pm}3nm$ can be successfully synthesized via the one-pot method. The scanning/transmission electronic microscope (SEM/TEM) images further show the samples are submicrospheres self-assembled by nanoparticles with size about 375-500 nm changed with reaction conditions. Room-temperature vibration magnetic strength measurements (VMS) demonstrates the as-obtained $ZnFe_2O_4$ submicrospheres show prefect superparamagnetism, whose coercivity force and remanence are practically nil. The reaction temperature and time influence on the crystallinity, diameter, saturated magnetic intensity and morphology of the particles.

• Journal of the Korean Magnetics Society
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• v.7 no.1
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• pp.19-24
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• 1997

Composition and process conditions for low temperature sintered NiCuZn ferrites were investigated, so as to fabricate multilayered chip inductor. The$Fe_2O_3$ deficiency for low temperature sintering was decreased with NiO contents of NiCuZn ferrites. The permeability of NiCuZn ferrites can be controlled in the range of 12~562 with the variation of NiO and $Co_3O_4$ contents. The $Q_{max} $ frequency of NiCuZn ferrites was decreased from 50 MHz to 3 MHz linearly with permeability increase from 60 to 560. The relation between the $Q_{max}$ frequency(Y) and permeability(X) of NiCuZn ferrites was expressed with the following empirical equation, logY=4.2-1.4logX.

• Economic and Environmental Geology
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• v.52 no.6
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• pp.529-539
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• 2019

In this study, heavy metal removal and precipitation characteristics with pH change were studied for artificial acid mine drainage. Artificial acid mine drainage was prepared using sulfates of iron, aluminum, copper, zinc, manganese which contained in acid mine drainage from abandoned mines. The single and mixed five heavy metal samples of Fe, Al, Cu, Zn, and Mn were prepared at initial concentrations of 30 and 70 mg/L. Fe and Al were mostly removed at pH 4.0 and 5.0, respectively, and other heavy metals gradually decreased with increasing pH. Concentration changes with increasing pH show generally similar trend for single and mixed heavy metal samples. The effect of removing heavy metals from aqueous solutions is not related to the initial concentration and depends on the pH change. XRD were used for mineral identification of precipitates and crystallinity of the mineral tended to increase with increasing pH. The precipitates that produced by decreasing the concentration of heavy metals in the aqueous solution composed of Fe-goethite(FeOOH), Al-basaluminite(Al₄(SO₄)(OH)₁₀·4H₂O), Cu-connellite(Cu₁₉(OH)₃₂(SO₄)Cl₄·3H₂O) and tenorite(CuO), Zn-zincite(ZnO), and Mn-hausmannite(Mn₃O₄).

• Journal of the Korean Magnetics Society
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• v.9 no.2
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• pp.78-84
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• 1999

$(Ni, Zn)Fe_2O_4$ powders were prepared through self-propagating high temperature synthesis reaction and the effects of initial zinc oxide powder size and oxygen pressure on the magnetic properties of the final combustion products were studied. The ferrite powders were combustion synthesized with iron, iron oxide, nickel oxide, and zinc oxide powders under various oxygen pressures of 0.5~10 atmosphere after blended in n-hexane solution for 5 minutes with a spex mill, followed by dried at 120 $^{\circ}C$ in vacuum for 24 hours. The maximum combustion temperature and propagating rate were about 1250 $^{\circ}C$ and 9.8 mm/sec under the tap density, which were decreased with decreasing ZnO size and oxygen pressure. The final product had porous microstructure with spinel peaks in X-ray spectra. As the ZnO particle size in the reactant powders and oxygen pressure during the combustion reaction increase, coercive force, maximum magnetization, residual magnetization, squareness ratio were changed from 1324 Oe, 43.88 emu/g, 1.27 emu/g, 0.00034 emu/gOe, 37.8$^{\circ}C$ to 11.83 Oe, 68.87 emu/g, 1.23 emu/g, 0.00280 emu/gOe, 43.9 $^{\circ}C$ and 7.99 Oe, 75.84 emu/g, 0.791 emu/g, 0.001937 emu/gOe, 53.8 $^{\circ}C$ respectively. Considering the apparent activation energy changes with oxygen pressure, the combustion reaction significantly depended on initial oxygen pressure and ZnO particle size.

• Korean Journal of Metals and Materials
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• v.50 no.6
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• pp.455-462
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• 2012

Al-Si coated boron steel and Zn coated DP steel plates were laser-welded to manufacture a Tailor Welded Blank (TWB) for a car body frame. Hot-stamping heat treatment ($900^{\circ}C$, 5 min) was applied to the TWB weld, and the microstructural change and transformation mechanism were investigated in the Al-rich area near the bond line of the Al-Si coated steel side. There was Al-rich area with a single phase, $Fe_3(Al,Si)$, which was transformed to ${\alpha}-Fe$ (Ferrite) after the heat treatment. It could be explained that the $Fe_3(Al,Si)$ phase was transformed to ${\alpha}-Fe$ during heat treatment at $900^{\circ}C$ for 5 min and the resultant ${\alpha}-Fe$ phase was not transformed by rapid cooling. Before the heat treatment, the microstructures around the $Fe_3(Al,Si)$ phase consisted of martensite, bainite and ${\alpha}-Fe$ while they were transformed to martensite and ${\delta}-Fe$ after the heat treatment. Due to the heat treatment, Al was diffused to the $Fe_3(Al,Si)$ and this resulted in an increase of Al content to 0.7 wt% around the Al-rich area. If the weld was held at $900^{\circ}C$ for 5 min it was transformed to a mixture of austenite (${\gamma}$) and ${\delta}-Fe$, and only ${\gamma}$ was transformed to the martensite by water cooling while the ${\delta}-Fe$ was remained unchanged.

• Journal of the Mineralogical Society of Korea
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• v.32 no.4
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• pp.303-312
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• 2019

In this study, X-ray diffraction, ICP analysis, and leaching experiments were performed to analyze the heavy metals and dissolution characteristics of Andong dam sediments. As a result of X-ray diffraction analysis, Andong dam sediment consists of quartz, plagioclase, chlorite and illite. ICP analysis of sediment showed very high concentrations of As and Cd. Leaching experiments were performed in aerobic and anaerobic condition in a disturbed state. The results of leaching experiment showed that more heavy metals were leached in aerobic than anaerobic conditions. Heavy metal that increased in concentration with time in aerobic conditions were Mn, Zn and Cd, and those in anaerobic conditions were Mn, Fe and As. The leaching ratio of heavy metal concentration in sediment was Mn > Cd > Zn > Ni > Cu > As > Pb ≒ Fe ≒ Cr and Mn > As > Cu > Ni > Zn > Pb ≒ Cd ≒ Fe ≒ Cr in aerobic and anaerobic conditions, respectively.