• Asian Journal of Atmospheric Environment
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• v.10 no.3
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• pp.162-167
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• 2016

This study was conducted in an industrial city (Bilaspur) representative of subtropical area in central India. In order to assess the metal deposition on plant, concentrations of six target metals (i.e., Fe, Mn, Pb, Cu, Cd, and Cr) in both plant leaf and dust (deposited on its surface) samples were measured from six different sites. Metal concentrations in dust samples were found on the order of Fe>Mn> Cr>Pb>Cu>Cd. In contrast, the concentration of metals in plant leaves were seen on the order of Fe>Mn>Cr>Cd>Cu>Pb. As such, Cd showed significantly high concentration in leaves relative to their corresponding dust samples. A high accumulation potential for Fe and Cd was seen from Butea monosperma, while Mn and Pb were accumulated noticeably in Pongamia pinnata and Butea monosperma. Likewise, Cr and Cu were enriched in Calotropis procera, Alstonia scholaris, and Butea monosperma. The overall results of our study suggest that the foliar uptake pattern should vary considerably by an interactive role between plant and metal types.

• Journal of Nutrition and Health
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• v.40 no.1
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• pp.41-48
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• 2007

The purpose of this study was to investigate the relationship between obesity and, erythrocyte SOD (superoxide dismutase) activity and serum antioxidant mineral (Fe, Zn, Cu, Mn and Se) concentrations of adolescents. Subjects were assigned to one of two groups such as obese ($BMI{\geq}25$, 32 boys, 24 girls) and normal group (18.5 < BMI < 23, 27 boys, 30 girls) Subjects were evaluated based on anthropometric measurements, 24-hr dietary recalls and blood analysis. The mean age of the total subjects was 13.8 years. The mean weight (p < 0.001), BMI (p < 0.001) and body fat (p < 0.001) of obese were higher than those of normal group. There was no significant difference in nutrient intake between obese and normal groups. SOD activity of obese group was not significantly different from normal groups, in both males and females. However, in the males, serum Cu concentration of obese were significantly lower than those of normal group. In the females, Serum Mn concentration of obese were significantly lower then those of normal group. In the correlation analysis, BMI of the subjects had significantly negative correlations with serum Cu, Zn and Mn. To summarize the results, increase of obesity may lead to decrease of serum antioxidant minerals such as Cu, Zn and Mn.

• Journal of Magnetics
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• v.10 no.4
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• pp.142-144
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• 2005

The Magnetization behaviour has been measured for amorphous $Fe_{80-x}Mn_xZr_{10}$ (x = 4,6,8,10) alloys. The Curie temperature decreased from 236 K to 195 K with increasing Mn concentration (x = 4 to x = 10). The magnetization measurements were conducted at temperatures above the Curie temperature in the paramagnetic region. In all samples, the magnetic properties showed superparamagnetic behavior above $T_c$ where the mean magnetic moment of the superparamagnetic spin clusters decreased with increasing temperature. A large magnetic entropy change, ${\Delta}S_M$, which is calculated from H vs M curves associated with the ferromagnetic-paramagnetic transitions in amorphous, has been observed. With Mn concentration increasing, ${\Delta}S_M$ decreases 1.04, 0.95, 0.87 J/kg K at 222, 210, 195 K (the Curie temperature), respectively.

• Journal of Environmental Health Sciences
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• v.27 no.4
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• pp.25-34
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• 2001

Heavy metal level and distribution in sediment and bivalves from the tidal flats along the mid-western coast, Korea. were investigated in this study. The averages of heavy metal concentrations in sediments from 5 sampling sites ranged from 86.35-187.77mg/kg for Mn. 13.25-17.73mg/kg for Zn.6.80-11.85mg/kg for Cr,4.28-6.25mg/kg for Ni, 1.85-3.09mg/kg for Cu, 0.004-0.02()mg/kg for Cd and 5.70-10.41 mg/kg for Pb, respectively. From the results of heavy metal concentrations in mussels, the levels of Mn and Fe concentrations in S. strictus collected from S1 antral S2 sites were particularly high. Deviations of heavy metal concentrations am(Ing the individual mussels from the same site could be largely minimized by selecting mussel samples of the limited range in body size(8.5-11cm). Among the mussels of the limited body size, heavy metal concentrations both in the flesh and in the whole soft part were not strongly related to the body size. It was shown that ,in S. strictus, Cu moves fast into the flesh parts after absorption, while Pb and Fe move fast into the non-flesh parts. Overally. the heavy metal concentration in the tends to increase with that in the whole soft parts. The concentration factors(heavy metal concentration in 5. strictus/heavy metal concentration in sediment) showed that, of the examined meta1s. Cd is the most cumulative in the body of S. strictus followed by Zn and Cu, while Mn, Cr. Ni and Pb are not cumulative.

• Korean Journal of Materials Research
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• v.14 no.8
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• pp.595-599
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• 2004

We investigated the structural, electrical and magnetic properties of Mn-doped $CuAlO_2$ delafossite ceramics ($CuAl_{1-x}Mn_{x}O_2,\;0\le\;x\;\le0.05$), synthesized by solid-state reaction method in an air atmosphere at a sintering temperature of $1150^{\circ}C$. The solubility limit of Mn ions in delafossite $CuAlO_2$ was found to be as low as about 3 $mol\%$. Positive Hall coefficient and the temperature dependence of conductivity established that non-doped $CuAlO_2$ ceramic is a variable-range hopping p-type semiconductor. It was found that the Mn-doping in $CuAlO_2$ rapidly reduced the hole concentration and conductivity, indicating compensation of free holes. The analysis of the magnetization data provided an evidence that antiferromagnetic superexchange interaction is the dominant mechanism of the exchange coupling between Mn ions in $CuAl_{1-x}Mn_{x}O$ alloy, leading to an almost paramagnetic behavior in this alloy.

• Corrosion Science and Technology
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• v.13 no.3
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• pp.102-106
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• 2014

Nickel electrodeposition from sulfamate bath has several benefits such as low internal stress, high current density and good ductility. In nickel deposited layers, sulfur induces high temperature embrittlement, as Ni-S compound has a low melting temperature. To overcome high temperature embrittlement problem, adding manganese is one of the good methods. Manganese makes Mn-S compound having a high melting temperature above $1500^{\circ}C$. In this work, the mechanical properties of Ni-Mn deposited layers were investigated by using various process variables such as concentration of Mn$(NH_2SO_3)_2$, current density, and bath temperature. As the Mn content of electrodeposited layers was increased, internal stress and hardness were increased. By increasing current density, internal stress increased, but hardness decreased. With increasing the bath temperature from 55 to $70^{\circ}C$, internal stress of Ni deposit layers decreased, but hardness didn't change by bath temperature. It was likely that eutectoid manganese led to lattice deformation, and the lattice deformation increased hardness and internal stress in Ni-Mn layers. Increasing current density and decreasing bath temperature would increase a mount of $H_2$ absorption, which was a cause for the rise of internal stress.

• Electrical & Electronic Materials
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• v.10 no.1
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• pp.33-38
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• 1997

The green emitting phosphors of the Field Emission Display(FED), Al codoped ZnGa$_{2}$O$_{4}$:Mn, were synthesized and sintered at high temperature. From X-ray diffraction measurements, it was confirmed that poly crystalline ZnGa$_{2}$O$_{4}$ and ZnAI$_{2}$O$_{4}$ solid solution coexist in Al codoped ZnGa$_{2}$O$_{4}$:Mn. Photoluminescence spectra of Al codoped ZnGa$_{2}$O$_{4}$:Mn show that the main peak position is shifted from 504 nm to 513 nm with the increase of Al concentration. The brightness was improved with the amount of Al dopant. It showed the maximum value at the doping level of 0.03 mole and then, it degraded rapidly. These results are due to the superposition of emission from . ZnGa$_{2}$O$_{4}$:Mn and ZnAI$_{2}$O$_{4}$:Mn.

• Korean Journal of Metals and Materials
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• v.46 no.5
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• pp.315-320
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• 2008

The effect of Mn additive on the thermoelectric properties of Fe-Si alloys prepared by a RF inductive furnace was investigated. The electrical conductivity and Seebeck coefficient were measured as a function of temperature under Ar atmosphere to evaluate their applicability to thermoelectric energy conversion. The electrical conductivity of the specimens increased with increasing temperatures showing typical semiconducting behavior. The electrical conductivity of Mn-doped specimens are higher than that of undoped specimens and increased slightly with increasing the amount of Mn additive. This must be due to the difference in carrier concentration and the amount of residual metallic phase ${\varepsilon}$-FeSi(The ${\varepsilon}$-FeSi was detected in spite of 100 h annealing treatment at $830^{\circ}C$). And metallic conduction increased slightly with increasing the amount of Mn additive. On the other hand, Mn-doped specimens showed the lower Seebeck coefficient due to metallic phase. The power factor of Mn-doped specimens are higher than that of undoped specimens and would be affected by the electrical conductivity more than Seebeck coefficient.

• Journal of Powder Materials
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• v.28 no.1
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• pp.38-43
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• 2021

A high NIR-reflective black pigment is developed by Mn doping of Fe2O3. The pigment powders are prepared by spray pyrolysis, and the effect of the Mn concentration on the blackness and optical properties is investigated. Mn doping into the crystal lattice of α-Fe2O3 is found to effectively change the powder color from red to black, lowering the NIR reflectance compared to that of pure Fe2O3. The pigment doped with 10% Mn, i.e., Fe1.8Mn0.2O3, exhibits a black color with an optical bandgap of 1.3 eV and a Chroma value of 1.14. The NIR reflectance of the prepared Fe1.8Mn0.2O3 black pigment is 2.2 times higher than that of commercially available carbon black, and this material is proven to effectively work as a cool pigment in a temperature rise experiment under near-infrared illumination.

• Korean Chemical Engineering Research
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• v.56 no.3
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• pp.349-355
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• 2018

$BaMnAl_{11}O_{19}$ was prepared by urea-induced homogeneous precipitation and characterized by X-ray diffraction and scanning electron microscopy. At increased precipitant concentrations, AlOOH replaced $Al(OH)_3$ as an Al precursor. $BaMnAl_{11}O_{19}$ exhibited enhanced catalytic combustion performance and inhibited CO generation. Catalytic performance was also enhanced by the presence of $BaAl_2O_4$ and $BaMnAl_{11}O_{19}$. Compared to $BaAl_2O_4$, $BaMnAl_{11}O_{19}$ exhibited superior catalytic combustion activity.