• Transactions on Electrical and Electronic Materials
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• v.18 no.1
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• pp.46-50
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• 2017

The Zn1-xMnxO ($0.00{\leq}x{\leq}0.06$) samples have been synthesized in the form of powder by the coprecipitation method at low temperature using $Zn(CH_3COO)_2$. $2H_2O$ and $Mn(CH_3COO)_2$. $4H_2O$ powders, as well as HCl and $NH_4OH$ solutions as starting materials. Characterization was conducted using XRD, TEM, XRF, FTIR and VSM. The result shows that the $Zn_{(1-x)}Mn_xO$ ($0.00{\leq}x{\leq}0.06$) nanoparticles have the wurtzite phase with a hexagonal structure and particle sizes ranging from 17.48 to 118.83 nm. In a qualitative analysis of XRF, the peaks that confirm the existence of the manganese element in Mn-doped ZnO samples were observed. Meanwhile, FTIR test result shows that there are peaks at around $500cm^{-1}$ and $400cm^{-1}$ in the FTIR spectra for Mn doped ZnO samples which clearly reveal the existence of the (Zn, Mn)-O strain mode. The (Zn, Mn)-O absorption peak positions have shifted to a lower wave number with increasing Mn doping content. The peak intensity is also lower if compared to that of the ZnO sample without doping. From the VSM test, it is shown that $Zn_{(1-x)}Mn_xO$ ($0.00{\leq}x{\leq}0.06$) nanoparticles are all paramagnetic having monotonically increased susceptibility as increasing Mn content.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.31 no.1
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• pp.16-23
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• 2021

Lithium carbonate recovered from the waste solution generated during the lithium secondary battery manufacturing process contains heavy metals such as cobalt, nickel, and manganese. In this study, the recrystallization of lithium carbonate was performed to remove heavy metals contained in the powder and to increase the purity of lithium carbonate. First, the leaching efficiency of lithium carbonate according to pH in the aqueous hydrochloric acid solution was examined, and the effect on the recrystallization of lithium carbonate according to the equivalent and concentration of sodium carbonate was confirmed. As the equivalent and concentration of sodium carbonate increased, the recovery rate of lithium carbonate improved. And the SEM image showed that the crystal shape was changed depending on the reaction conditions with sodium carbonate. Finally, the high purity lithium carbonate of 99.9% or more was recovered by washing with water.

• Journal of Preventive Medicine and Public Health
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• v.31 no.4 s.63
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• pp.666-679
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• 1998

This study aims at providing the fundamental data on the field of cosmetics by comparing heavy metal concentration in terms of domestic/foreign products, items, companies and colors. This study has determined the concentration of chromium, lead, mangagnese, nickel, copper and vanadium in cosmetics such as moisturizer, concealer, foundation (Ivory-yellow), compact powder (Ivory-yellow), lip colo. (Red, brown), eye shadow (Red, brwon and dark green) and eye liner (Black) manufactured by five domestic cosmetic companies and five foreign cosmetic companies on the market. The samples have been collected in cosmetic stores in Pusan from Dec. lst 1996 to Jan. 3lst 1997. The results are as follows : 1. The heavy metal concentration in cosmetics was $2.420{\mu}g/g$ for chromium, $0.82{\mu}g/g$ for lead, $4.49{\mu}g/g$ for manganese, $1.69{\mu}g/g$for nickel, $0.53{\mu}g/g$ for copper, and $51{\mu}g/g$ for vanadium, respectively. 2. Lead and vanadium concentration were significantly higher in domestic cosmetics than foreign cosmetics(p<0.05). 3. The mean(GM) concentrations of heavy metal were different significantly (p<0.01) when classified with cosmetic items. The highest means shown at eye shadow in $Cr(14.96{\mu}g/g),\;Cu(1.32{\mu}g/g),\;V(1.28{\mu}g/g),\;and\;Ni(8.30{\mu}g/g)$, compact powder in $Pb(2.50{\mu}g/g)$, eye liner in $Mn(90.62{\mu}g/g)$. 4. The mean(GM) concentrations of heavy metal were different significantly (p<0.01) among colored cosmetics. The highest mean concentration of Cr, Ni, Cu and V were dark green-colored cosmetics, that of Mn was black-colored cosmetics, and that of Pb was ivory yellow- colored cosmetics.

• Resources Recycling
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• v.32 no.1
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• pp.21-32
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• 2023

Because the application of lithium has gradually increased for the production of lithium ion batteries (LIBs), more research studies about recycling using solvent extraction (SX) should focus on Li⁺ recovery from the waste solution obtained after the removal of the valuable metals nickel, cobalt and manganese (NCM). The raffinate obtained after the removal of NCM metal contains lithium ions and other impurities such as Na ions. In this study, we optimized a selective SX system using di-(2-ethylhexyl) phosphoric acid (D2EHPA) as the extractant and tri-n-butyl phosphate (TBP) as a modifier in kerosene for the recovery of lithium from a waste solution containing lithium and a high concentration of sodium (Li⁺ = 0.5 ~ 1 wt%, Na⁺ = 3 ~6.5 wt%). The extraction of lithium was tested in different solvent compositions and the most effective extraction occurred in the solution composed of 20% D2EHPA + 20% TBP + and 60% kerosene. In this SX system with added NaOH for saponification, more than 95% lithium was selectively extracted in four extraction steps using an organic to aqueous ratio of 5:1 and an equilibrium pH of 4 ~ 4.5. Additionally, most of the Na⁺ (92% by weight) remained in the raffinate. The extracted lithium is stripped using 8 wt% HCl to yield pure lithium chloride with negligible Na content. The lithium chloride is subsequently treated with high purity ammonium bicarbonate to afford lithium carbonate powder. Finally the lithium carbonate is washed with an adequate amount of water to remove trace amounts of sodium resulting in highly pure lithium carbonate powder (purity > 99.2%).

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.2
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• pp.237-244
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• 2007

An experiment was conducted to study the growth performance, bone mineralization and mineral excretion in broiler starter chicks fed high levels of cholecalciferol (CC) at sub-optimal levels of calcium (Ca) and non-phytate phosphorus (NPP). Five hundred and sixty day-old Vencobb female broiler chicks were housed in raised wire floor stainless steel battery brooder pens ($24"{\times}30"{\times}18"$) at the rate of five chicks per pen. A maize-soyabean meal basal diet was supplemented with dicalcium phosphate, oyster shell powder and synthetic CC to arrive at two levels each of Ca (0.50 and 0.60%), and NPP (0.25 and 0.30%) and four levels of CC (200, 1,200, 2,400 and 3,600 ICU/kg) in a $2{\times}3{\times}4$ factorial design. Each diet was fed ad libitum to chicks in 7 pens from 2 to 21days of age. Body weight gain, feed intake and bone weight increased (p<0.05) with increase in level of CC at both the Ca and NPP levels tested. The CC levels required to obtain significant improvement in body weight gain and feed intake reduced (2,400 ICU/kg vs. 1,200 ICU/kg) with increase in levels of P in diet (0.25% vs. 0.3%, respectively). The feed conversion ratio was significantly improved (p<0.05) with increase in level of CC from 200 to 1,200 ICU/kg diet at 0.5% Ca, while at 0.6% Ca, the level of CC in diet did not influence the feed efficiency. Tibia mineralization (density, breaking strength and ash content) and Ca and P contents in serum increased significantly (p<0.05) with increase in levels of CC in diet. The CC effect on these parameters was more pronounced at lower levels of Ca and NPP (0.5 and 0.25%, respectively). The data on body weight gain and feed intake indicated that NPP level in diet can be reduced from 0.30 to 0.25% by increasing CC from 200 to 2,400 ICU/kg. Similarly, the bone mineralization (tibia weight, density and ash content) increased non-linearly (p<0.01) with increase in CC levels in diet. Concentrations of P and Mn in excreta decreased (p<0.01), by increasing CC level from 200 to 2,400 ICU/kg diet. It can be concluded that dietary levels of Ca and NPP could be reduced to 0.50 and 0.25%, respectively by enhancing the levels of cholecalciferol from 200 to 2,400 ICU/kg with out affecting body weight gain, feed efficiency and bone mineralization. Additionally, phosphorus and manganese excretion decreased with increase in levels of CC in broiler diet.

• Korean Journal of Food Science and Technology
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• v.25 no.6
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• pp.769-774
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• 1993

Defatted rice bran was microparticulated using fluidized bed opposed jet mill and air-classified at different air classifying wheel speed (ACWS) in Turboplex classifier. The median particle size and the standard deviation decreased, and concomitantly the specific surface area increased generally with increasing ACWS. The protein, fat and ash contents of the recovered rice bran increased with ACWS. The contents of minerals; magnesium, zinc, iron and manganese; increased positively with ACWS. The phytic acid content, however, was slightly higher at middle ACWS. The dietary fiber content was highest in the ACWS 15,000 rpm fraction showing 31.47%. Higher ACWS resulted in lighter colored powder. The water holding capacity (WHC) showed the maximum value at ACWS 12,000 rpm and decreased with increasing ACWS, while the oil holding capacity (OHC) increased with ACWS. The rheological property of the microparticulated rice bran/water suspension fitted to the linear model. The yield stress and viscosity of the suspension increased with ACWS. The shape of microparticulated rice bran at ACWS 21,000 rpm was spherical, and the median particle size was $3.7{\mu}m$. When cake was prepared with substitution of microparticulated rice bran at 5%, the cake height and volume increased remarkably.

• Economic and Environmental Geology
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• v.8 no.3
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• pp.117-124
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• 1975

Wet chemical analysis (for $MnO_2$, MnO, and $H_2O$(+)) and electron microprobe analysis (for $Fe_2O_3$ and PbO) give $MnO_2$ 74.91, MnO 11.33, $Fe_2O_3$ (total Fe) 4.19, PbO 0.03, $H_2O$ (+) 9.46, sum 99.92%. 'Available oxygen determined by oxalate titration method is allotted to $MnO_2$ from total Mn, and the remaining Mn is calculated as MnO. Traces of Ba, Ca, Mg, K, Cu, Zn, and Al were found. Li and Na were not found. The existence of (OH) is verified from the infrared absorption spectra. The analysis corresponds to the formula $Mn^{4+}{_{4.85}}(Mn^{2+}{_{0.90}}Fe^{3+}{_{0.30}})_{1.20}O_{8.09}(OH)_{5.91}$, on the basis of O=14, 'or ideally $Mn^{4+}{_{5-x}}(Mn^{2+},Fe^{3+})_{1+x}O_{8}(OH)_{6}$ ($x{\approx}0.2$). X-ray single crystal study could not be made because of the distortion of single crystals. But the x-ray powder pattern is satisfactorily indexed by an orthorhombic cell with a 9.324, b 14.05, c $7.956{\AA}$., Z=4. The indexed powder diffraction lines are 9.34(s) (100), 7.09(s) (020), 4.62(m) (200, 121), 4.17(m) (130), 3.547(s) (112), 3.212(vw) (041), 3.101(s) (300), 2.597(w) (013), 2.469(m) (331), 2.214(vw)(420), 2.098(vw) (260), 2.014 (vw) (402), 1.863(w) (500), 1.664(w) (314), 1.554(vw) (600), 1.525(m) (601), 1.405(m) (0.10.0). DTA curve shows the endothermic peaks at $250-370^{\circ}C$ and $955^{\circ}C$. The former is due to the dehydration: and oxidation forming$(Mn,\;Fe)_2O_3$(cubic, a $9.417{\AA}$), and the latter is interpreted as the formation of a hausmannite-type oxide (tetragonal, a 5.76, c $9.51{\AA}$) from $(Mn,\;Fe)_2O_3$. Infrared absorption spectral curve shows Mn-O stretching vibrations at $515cm^{-1}$ and $545cm^{-1}$, O-H bending vibration at $1025cm^{-1}$ and O-H stretching vibration at $3225cm^{-1}$. Opaque. Reflectance 13-15%. Bireflectance distinct in air and strong in oil. Reflection pleochroism changes from whitish to light grey. Between crossed nicols, color changes from yellowish brown with bluish tint to grey in air and yellowish brown to grey through bluish brown in oil. No internal reflections. Etching reactions: HCl(conc.) and $H_2SO_4+H_2O_2$-grey tarnish; $SnCl_2$(sat.)-dark color; $HNO_3$(conc.)-grey color; $H_2O_2$-tarnish with effervescence. It is black in color. Luster dull. Cleavage one direction perfect. Streak brownish black to dark brown. H. (Mohs) 2-3, very fragile. Specific gravity 3.59(obs.), 3.57(calc.). It occurs as radiating groups of flakes, flower-like aggregates, colloform bands, dendritic or arborescent masses composed of fine grains in the cementation zone of the supergene manganese oxide deposits of the Janggun mine, Bonghwa-gun, southeastern Korea. Associated minerals are calcite, nsutite, todorokite, and some undetermined manganese dioxide minerals. The name is for the mine, the first locality. The mineral and name were approved before publication by the Commission on New Minerals and Mineral Names, I.M.A.

• Journal of Nutrition and Health
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• v.39 no.5
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• pp.433-443
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• 2006

The effects of Allium vegetables on blood glucose levels and lipid metabolism in streptozotocin (S12) induced diabetic rats were investigated. Diabetes mellitus was induced by S1'2 injection (45 mg/kg 5.w.) into the tail vein. Sprague-Dawley rats weighing $220\;{\pm}\;10\;g$ were randomly assigned to 7 groups: normal, S1'2-control and five Allium groups (Allium cepa, Allium fistulosum, Allium sativum, Allium tuberosum and Allium victorialisL Normal and S12control groups were fed an AIN-93 diet and five Allium groups were fed a modified diet containing. 10% Allium powder each for 4 weeks. Body weight, diet intake, food efficiency ratio (FER) and organ weights- were monitored. Activities of aspartate aminotransferase (AST) & alanine aminotransferase (ALT) were observed: Plasma lev~ls of glucose, free fatty acid, triglyceride and HDL-cholesterol were analyzed. Levels of glycogen, cholesterol and triglyceride in liver were determined. Levels of malondialdehyde (MDA) in liver, lung, kidney, and pancreas were assayed. The hepatic contents of chromium (Cr) , iron (Fe), zinc (Zn) and manganese (Mu) were measured. The Allium sativum group had weight gain and suppressed a hypertrophy of the kidney significantly. The activity of ALT was significantly lowered in the diabetic groups except Allium sativum group compared to STZ-control group. The Allium sativum and Allium tuberosum groups showed the hypoglycemic effects at 4 weeks. There were no significant differences between the control and all the other diabetic groups in the plasma levels of cholesterol, HDL-cholesterol, triglycerides and free fatty acids. Most of the Allium groups except Allium fistulosum were observed significantly lowered level of MDA in the lung compared to STZ-control group. The diabetic rats fed the Allium cepa and Allium sativum have shown significantly lowered hepatic Zn contents. The results suggested that the intake of the Allium vegetables may be effective in the antihyperglycemia by lowering blood glucose levels.

• Journal of the Korean Applied Science and Technology
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• v.20 no.1
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• pp.33-43
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• 2003

$LiMn_2O_4$ catalyst for $CO_2$ decomposition was synthesized by oxidation method for 30 min at 600$^{\circ}C$ in an electric furnace under air condition using manganese(II) nitrate $(Mn(NO_3)_2{\cdot}6H_2O)$, Lithium nitrate ($LiNO_3$) and Urea $(CO(NH_2)_2)$. The synthesized catalyst was reduced by $H_2$ at various temperatures for 3 hr. The reduction degree of the reduced catalysts were measured using the TGA. And then $CO_2$ decomposition rate was measured using the reduced catalysts. Phase-transitions of the catalysts were observed after $CO_2$ decomposition reaction at an optimal decomposition temperature. As the result of X-ray powder diffraction analysis, the synthesized catalyst was confirmed that the catalyst has the spinel structure, and also confirmed that when it was reduced by $H_2$, the phase of $LiMn_2O_4$ catalyst was transformed into $Li_2MnO_3$ and $Li_{1-2{\delta}}Mn_{2-{\delta}}O_{4-3{\delta}-{\delta}'}$ of tetragonal spinel phase. After $CO_2$ decomposition reaction, it was confirmed that the peak of $LiMn_2O_4$ of spinel phase. The optimal reduction temperature of the catalyst with $H_2$ was confirmed to be 450$^{\circ}C$(maximum weight-increasing ratio 9.47%) in the case of $LiMn_2O_4$ through the TGA analysis. Decomposition rate(%) using the $LiMn_2O_4$ catalyst showed the 67%. The crystal structure of the synthesized $LiMn_2O_4$ observed with a scanning electron microscope(SEM) shows cubic form. After reduction, $LiMn_2O_4$ catalyst became condensed each other to form interface. It was confirmed that after $CO_2$ decomposition, crystal structure of $LiMn_2O_4$ catalyst showed that its particle grew up more than that of reduction. Phase-transition by reduction and $CO_2$ decomposition ; $Li_2MnO_3$ and $Li_{1-2{\delta}}Mn_{2-{\delta}}O_{4-3{\delta}-{\delta}'}$ of tetragonal spinel phase at the first time of $CO_2$ decomposition appear like the same as the above contents. Phase-transition at $2{\sim}5$ time ; $Li_2MnO_3$ and $Li_{1-2{\delta}}Mn_{2-{\delta}}O_{4-3{\delta}-{\delta}'}$ of tetragonal spinel phase by reduction and $LiMn_2O_4$ of spinel phase after $CO_2$ decomposition appear like the same as the first time case. The result of the TGA analysis by catalyst reduction ; The first time, weight of reduced catalyst increased by 9.47%, for 2${\sim}$5 times, weight of reduced catalyst increased by average 2.3% But, in any time, there is little difference in the decomposition ratio of $CO_2$. That is to say, at the first time, it showed 67% in $CO_2$ decomposition rate and after 5 times reaction of $CO_2$ decomposition, it showed 67% nearly the same as the first time.

• Journal of the Korean Society of Food Culture
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• v.21 no.3
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• pp.297-302
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• 2006

This study has examined the physicochemical properties of the Pleurotus eryngii, including their proximate components, amount mineral content, total dietary fiber, total sugar, reducing sugar and free sugar. Additionally, it measured the P. egii ethanol extracts and the total amounts of polyphenol compounds as well as its electron donating ability (EDA) of the substance fraction (SF). The P. eryngii powder's moisture content was 9.0% and each of the other element content such as carbohydrate, crude protein, crude ash and crude fat was found to be 63.06%, 20.70%, 5.20% and 2.0% respectively. Potassium (K) was shown to be the greatest inorganic content and manganese (Mn) was the lowest. Furthermore fructose, galactose, glucose lactose and maltose free sugar content was found in this order. 387 mg% of the total amounts of polyphenol was found in the P. eryngii whole body ethanol extract, 158 mg% in the stipe extract, 593 mg% in the pileus extract and 607 mg% in the substance fraction (SF). Electron donating ability (EDA) was highest at 91.12% in the whole body extract and lowest at 62.90% in the stipe extract. Additionally, the EDA for substance fraction (SF) 0.02%-0.1% was found to be 57.78-77.33%, which was lower than the 0.02%-tocopherol (93.92%) and BHT (96.72%). From these results, it can be assumed that P. eryngii offers superior antioxidative effects with its high content of fiber, inorganic materials and total amounts of polyphenol as well as high electron donating ability (EDA), thereby making it ideal for use in functional foods and industrial materials.