• Journal of Korean Society of Forest Science
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• v.90 no.1
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• pp.74-82
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• 2001

The effects of Al and Mn concentration on dry weight growth, nutrient status and gas exchange rates of 2-Year-old Japanese red pine(Pinus densiflora) seedlings grown in a nutrient culture solution were investigated. Al was added as aluminum chloride at 0, 10, 30 or 60ppm, and Mn was added as manganese chloride at 0, 30 or 60ppm to the nutrient culture solution. The pH of the solution was maintained at 4.0 by adding HCl or NaOH solution. The seedlings were transplanted into the nutrient culture solution, then they were grown in a greenhouse for 90 days. The interactive effects of Al and Mn on the dry weight growth of the seedlings were not significant. There were a main effect of Al or Mn on the dry weight growth and element concentrations of the seedlings. The treatment with Al of ${\geq}10ppm$ or that with Mn of 60ppm induced a significant reduction in the dry weight growth, which indicates that the effect of Al is stronger than that of Mn. The chlorophyll content of needles was not affected by Al treatment, but was significantly reduced by treatment with Mn of 60ppm. Furthermore, the treatment with Al of 60ppm or that with Mn of ${\geq}30ppm$ caused a significant reduction in the dark respiration rate of the roots. The net photosynthetic rate of the seedlings reduced with increasing the concentration of Al or Mn in the nutrient culture solution, which suggests that Al or Mn induced reductions in the relative growth rate(RGR) and net assimilation rate(NAR) of the seedlings were mainly due to the decrease of net photosynthesis.

• Resources Recycling
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• v.24 no.6
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• pp.24-30
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• 2015

The sulfuric acid leaching of ferromanganese dust was studied. The effect of acid concentration, reaction temperature, stirring rate, particle size and solid to liquid ratio on Mn and Fe extraction in the solution were investigated. It was found that the leaching rate of Mn and Fe increased with increasing reaction temperature and sulfuric acid concentration. Examination of data by shrinking core model suggested that the leaching rate is controlled by chemical reaction at the surface of particle. The activation energy for the leaching reaction of Mn and Fe were calculated to be 79.55 kJ/mol and 77.48 kJ/mol, respectively.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.24 no.1
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• pp.27-31
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• 2011

ZnS:Mn yellow phosphors doped with Sm for white light emitting diodes were synthesized by solid state reaction method. These sample showed the characteristic X-ray diffraction patterns for main peak (110) of ZnS:Mn,Sm. Photoluminescence excitation spectra originated from $Mn^{2+}$ were ranged from 450 nm to 500 nm. The yellow emission at around 580 nm was associated with $^4T_1{\rightarrow}^6A_1$ transition of $Mn^{2+}$ ions in ZnS:Mn,Sm phosphors. The highest photolum inescence intensity of the phosphors under 405 nm and 450 nm excitation was obtained at Sm concentration of 1 mol%. The enhanced photoluminescent intensity in the ZnS:Mn,Sm phosphors was interpreted by energy transfer from Sm to Mn. The highest luminescent intensity of white LED was obtained at the epoxy-to-yellow phosphor ratio of 1:3. At this ratio, the CIE chromaticity of the white LED was X=0.3886 and Y=0.2928.

• Resources Recycling
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• v.26 no.4
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• pp.34-41
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• 2017

The effect of Mn(II) concentration on the anodic reactions occurring on a Pb-Ag electrode in sulfuric acid solutions has been studied by potentiostatic oxidation in the potential range of 1.8 to 2.0 V. High oxidation potentials and low initial concentrations of Mn(II) resulted in higher concentrations of soluble Mn(III) ions which were obtained from spectrophotometric analysis of the solution after oxidation. $MnO_2$ was deposited on the electrode by electrochemical oxidation of Mn(II) at 1.8 and 1.9 V, while it was formed by disproportionation of Mn(III) at 2.0 V. No $PbO_2$ was formed in the presence of Mn(II) during potentiostatic oxidation treatment for two hours at 1.8 V. Chemical reduction of $PbO_2$ with Mn(II) led to a decrease in the amount of $PbO_2$ as Mn(II) concentration increased at 1.9 and 2.0 V.

• Journal of the Korean Ceramic Society
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• v.27 no.1
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• pp.7-12
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• 1990

The influence of MnO2 on the sintering property and PTCR behavior of(Ba0.8Sr0.2)TiO2 has been investigated. And the densities, grain sizes and electrical resitivities of specimens were measured as a function of doping with Mn ion of varying concentration. The density and grain size of the sintered specimens were almost the same regardless of MnO2 addition up to 0.2mol% MnO2. But in the case of 0.25mol% MnO2 addition, abnormal grain growth was appeared. So the grain size distribution was wide and density decreased greatly. The room-temperature resistivity increased as Mn content increased and the temperature coefficient of resistivity was highest in the case of 0.15mol% MnO2 addition.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.5
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• pp.415-418
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• 2009

$Zn_{2}SiO_{4}$:Mn green phosphors doped with Mg for PDP were synthesized by solid state reaction method. $Zn_{2}SiO_{4}$:Mn, Mg phosphors with increasing Mg concentration were changed from Rhombohedral to Orthorhombic structure. Photoluminescence intensity of $Zn_{2}SiO_{4}$:Mn phosphors doped with Mg 0.5 mol was definitely higher than that of Mg non-doped sample. The enhanced luminescence with doping Mg in the $Zn_{2}SiO_{4}$:Mn phosphors was interpreted by the increase of energy transfer from host to Mn ions with substitution Mg for Zn in the $Zn_{2}SiO_{4}$:Mn host.

• Journal of Plant Biology
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• v.10 no.3_4
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• pp.4-9
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• 1967

The aim of present study is to elucidate the effects of manganese and aluminium ions on the germination and seedling growth of Pinus banksiana and Alnus tinctoria and to estimate the limiting level of those ions in the cultivated soils. The rate of germination of Pinus banksiana was increased under the relatively low concentration of Mn and Al (100 p.p.m), however, the germinating activity was not affected. High concentration over 110 p.p.m. of Mn and Al was related to the reduced percentage of germination and seedling growth of Pinus banksiana and Alnus tinctoria. Soils sampled from various parts of Korea contained Mn as much as high level that would be harmful for the seedling growth of Pinus banksiana and Alnus tinctoria.

• Journal of the Korean Ceramic Society
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• v.34 no.4
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• pp.394-398
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• 1997

Mn-Zn ferrite powders were prepared by alcoholic dehydration, using coprecipitation method. Then the effects of organic dispersant and polymeric binder concentration on stability and casting of slurry were discussed. Citric acid, the organic dispersant and polyvinylacohol(PVA), the non-ionic binder, were selected as additives of slurry. With variation of concentration of water, citric acid and polyvinylalcohol(PVA), optimum forming conditions were determined from viscosity and density. To compare with dry process, density and microstructure of sintered body formed by uniaxial die pressing were observed.

• Journal of the Korean Wood Science and Technology
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• v.29 no.4
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• pp.40-47
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• 2001

To remove $Zn^{2+}$(422 ppm) and $Mn^{2+}$(53.1 ppm) from Sambo mine runoff(the total amount of heavy metals : 107 ppm) in Whasung, packed bed column tests were run in two stages plastic columns. The non-treated bark(Pinus densiflora, Quercus accutisima) of each 6 kg were placed into columns. The height and diameter of column were 60 cm and 45 cm, respectively. Flow rate ranged to 1 ${\ell}$/min for 15 days. The concentration of heavy metal ions in filtrate was determinded periodically. By the treatment of oak bark the initial concentration of $Zn^{2+}$ was maintained under 10 ppm(the adsorption rate: 64%) for 24 hr, while pine bark kept the initial concentration of $Zn^{2+}$ under 20 ppm(the adsorption rate: 53%) for 15 hr. However the initial concentration of $Mn^{2+}$ was reduced only to 10.6~18.6 ppm (the adsorption rate: 20~35%) until 10 hr. Thereafter, the adsorption of $Mn^{2+}$ by bark decreased rapidly. There was little difference in the adsorption ratio of $Mn^{2+}$ between oak and pine bark. The use of bark to remove $Zn^{2+}$ in Samba mine runoff was effective, but it wasn't proper to remove $Mn^{2+}$.

• Journal of Convergence for Information Technology
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• v.10 no.12
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• pp.183-190
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• 2020

This study evaluated the possibility of Hoangtonogak Plus extracts as a bioactive ingredients for cosmetic products. Methanol(MN) and hot-water(WN) extracts were analysed by DPPH/ABTS radical scavenging activity, FRAP value for anti-oxidant activity, MTT assay for cell viability, inhibition of NO production and iNOS protein expression for anti-inflammatory effect, paper disc diffusion method for anti-microbial activity against Staphylococcus aureus, Staphylococcus epidermidis and Escherichia coli.. The contents of total polyphenol of MN and WN extracts were 2.92±0.01 mgGAE/g and 1.67±0.02 mgGAE/g, respectively. DPPH, ABTS and FRAP values of MN extracts were higher than WN at each concentration. No significant cytotoxicity was observed in RAW264.7 cells. Furthermore, NO production of MN and WN at 1 mg/mL concentration was measured as 11.69 μM, 20.4 μM, respectively. In addition, MN extracts showed anti-microbial effect only on S. epidermidis. Also MN extracts suppressed iNOS protein level in a concentration-dependent manner. According to our results, the MN extracts demonstrated its potential as a natural source of antioxidant with anti-microbial and anti-inflammatory properties.