• Bulletin of the Korean Chemical Society
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• v.28 no.3
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• pp.417-420
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• 2007

Mononuclear mixed-anions Mn complex of TPAMn(η2-NO3)(η-ClO4), where TPA is tris(2-pyridylmethyl)-amine, has been synthesized and characterized. The neutral TPAMn(η2-NO3)(η-ClO4) was obtained from the reaction between Mn(NO3)2·4H2O and [H3TPA](ClO4)3 in MeOH. X-ray crystallographic structure of mononuclear TPAMn(η2-NO3)(η-ClO4) complex showed a seven-coordinated geometry with a tripodal tetradentate TPA, a terminal perchlorate and an η2-bound nitrate.

• Economic and Environmental Geology
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• v.34 no.1
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• pp.89-104
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• 2001

The Chonju and Samchun streams are passing though Chonju city and several contamination sources are located along these streams. The Samchun stream joins the Chonju stream in the Gosapyeong waste disposal site and the Chonju stream finally joins to the Mankyeong River. The objectives of this study are to determine the state and sources of contamination for heavy metals and anions in the Chonju and Samchun streams and to evaluate the effect of these streams on the contamination of the Mankyeong River. In order to select sampling locations, a stratified random sampling method was used. These streams was divided into several parts according to the expected contamination state, and samples were selected randomly from these parts. Generally, the water qualities of these streams were generally below the Drinking Water Level at the time of sampling in various heavy metals and anions. However, the levels of AI, Fe, $NH_{3}-N,Cl^{-}$, Cl- in these streams could be higher during dry season due to continuous inputs from various contamination sources. This study identified several contamination sources for these streams; two waste disposal sites along these streams for Fe, Mn, AI, Zn and $Cl^{-}$, the Chonju Waste Water Treatment Plant for Zn, Mn, $Cl^{-}$, $SO_{4}S$, $NO_{2}N$, and $NH_{3}-N$ and the untreated sewages for AI, Zn, Mn, $Cl^{-}$, $SO_{4}S$, $NH_{3}-N$ and $PO_{4}^{2-}$. This study also revealed that the Chonju stream itself is an important contamination source for Fe, Mn, $Cl^{-}$ and $SO_{4}S$ in the Mankyung River.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.3
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• pp.359-364
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• 1995

This experiment was conducted to get the fundamental information about the difference in color and some chemical components of grey flue-cured tobacco cultivated in paddy field to compare with normal tobacco. Cured leaves of NC82 were separated with visual characters into three classes of slight, fair and severe symptoms of grey leaf by percentage of grey parts to whole leaf area, and compared to normal ones. Occurrence of grey leaves tended to be higher in lower stalk position than in upper ones. Cl, Mn and Fe content of grey leaves was much higher when it compared with normal leaves, and within the same leaf, grey parts were increased in Fe, Mn and Cl content than in those of normal parts but there was no appearent difference in total sugar, nicotine and Ca contents. Chemical analysis of grey leaf samples indicated that they contained more Fe, Mn and Cl contents than those of normal leaves. These tendencies in chemical traits were accordance with the degree of grey symptoms. Grey leaves showed remarkably lower b*value and slightly lower L*value than those of normal leaves, while a*value was mostly higher in grey leaves. In general, grey appearence of grey flue-curd tobacco seemed to be from less yellowish color, poorer brightness with more brownish or reddish color.

• Journal of Sensor Science and Technology
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• v.15 no.5
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• pp.323-327
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• 2006

Manganese, copper and chlorine-doped ZnS phosphors (ZnS:Mn,Cu,Cl) were synthesized through solid-state reaction. Manganese was added in the range of amount $1.4{\sim}5.3$ mol % to ZnS phosphors containing 0.2 or 1.0 mol % of copper and a small amount of chlorine. As-synthesized phosphors showed a spherical morphology with a mean size of ${\sim}20\;{\mu}m$ and structural properties of Wurtzite, which were identified by SEM and XRD, respectively. Optical properties of ZnS:Mn,Cu,Cl synthesized with various concentrations of activators were analysed by both of PL and EL spectra. Samples mainly showing only 580 nm-orange emission by 380 nm-UV excitation gave different EL spectra of blue, green, and orange emissions at 450, 480 and 580 nm, respectively, depending on concentrations of $Cu^{2+}$ and $Mn^{2+}$.

• Journal of Magnetics
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• v.2 no.4
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• pp.126-129
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• 1997

We have studied magnetostructural phase transitions in the perovskite-type layered structure compound (C18H37NH3)2 MnCl4 by means of electron paramagnetic resonance (EPR) and superconducting quantum interference device (SQUID) measurements. Distinct slopes were observed in the linear temperature dependences of the Mn++ EPR linewidth in the low and high temperature phases. Besides, linewidth anomalies at the transition temperatures sensitively reflect the magnetic changes arising from the MnCl6 octahedra.

• Journal of the Korean Ceramic Society
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• v.40 no.7
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• pp.652-656
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• 2003

The green emitting phosphor, BnGa$_2$O$_4$:Mn thin films with spinel structure were deposited by rf magnetron sputtering at various Ar/O$_2$ ratios. Thin film phosphors were heat-treated in air and $N_2$+vacuum atmosphere, respectively. Effects of Ar/O$_2$ ratios and annealing conditions on the structural and photoluminescence (PL) and cathodeluminescence (CL) properties were investigated. Luminous properties were more improved by inhibiting the films from contacting with oxygen during heat treatment.

• Journal of the Korean Magnetic Resonance Society
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• v.23 no.2
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• pp.40-45
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• 2019

The phase transition temperatures and thermodynamic properties of $(NH_4)_2MnCl_4{\cdot}2H_2O$ grown by the slow evaporation method were studied using differential scanning calorimetry and thermogravimetric analysis. A structural phase transition occurred at temperature $T_{C1}$ (=264 K), whereas the changes at $T_{C2}$ (=460 K) and $T_{C3}$ (=475 K) seemed to be chemical changes caused by thermal decomposition. In addition, the chemical shift and the spin-lattice relaxation time $T_{1{\rho}}$ were investigated using $^1H$ magic-angle spinning nuclear magnetic resonance (MAS NMR), in order to understand the role of $NH_4{^+}$ and $H_2O$. The rise in $T_{1{\rho}}$ with temperature was related to variations in the symmetry of the surrounding $H_2O$ and $NH_4{^+}$.

• Journal of Life Science
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• v.13 no.5
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• pp.658-667
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• 2003

Antioxidative enzymes (superoxide dismutase; SOD, ascorbate peroxidase; APX, glutathione reductase; GR) play major roles in scavenging mechanism of reactive oxygen species which were involved in various stress conditions including salt. In order to investigate the relation between their growth responses (dry weight) and the changes of antioxidative enzymes activity, salt-tolerant spinach beet having 15cm of shoot length were treated with various salt levels (0, 50, 200, 1000 mM NaCl) for 24 hours. Spinach beet exhibited an increase in the activity of antioxidative enzymes by salt, the maximal activity at 200 mM NaCl and the lowest activity at 50 mM NaCl in 2 hrs. after treatments. As a result of PAGE, it has been confirmed that spinach beet contained 3 isoforms (Fe-SOD, CuZn-SOD and Mn-SOD) of SOD and main isoform was CuZn- SOD form. In case of APX, isoforms of the low molecular weight(No. 7, 8) were showed strong expression especially at 200 and 400 mM NaCl treatment. Meanwhile, GR did not show specific pattern of isoforms among the salt treatments. Especially, in case of 50 mM treatment, plant showed the lowest activity of SOD with the best growth, a low enzyme activity was induced by inactivation of the Mn-SOD. Therefore, we suggested that the decrease of SOD activity at a low salt level (50 mM NaCl) or the increase of enzyme activity at a high salt level (200 mM NaCl) may be related to expression of the Mn-SOD isoform. These antioxidative enzymes showed the increase of activity in a short time by salt addition. So, it is considered that spinach beet copes effectively with a stressful condition such as salt by operating effective antioxidative defense mechanism rapidly under high salt level.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.1093-1095
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• 2006

An orange-emitting phosphor for inorganic electroluminescent device has been studied. Cu and Cl were co-doped in Mn-doped ZnS for a high-performing phosphor. The effect of $Mn^{2+}-doping$ concentration as well as $Mg^{2+}-sensitizer$ addition on the luminescence characteristics has been investigated.

• Progress in Medical Physics
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• v.18 no.1
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• pp.42-47
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• 2007

Purpose: To evaluate the tracing of optic nerve tract using manganese enhanced magnetic resonance Imaging. Materials and Methods: After injecting $30{\mu}l$ of $MnCl_2(1mol)$ (1 mol) Into the retina of female New Zealand white rabbit, the contrast enhancements at major anatomical structures of optic nerve tract were evaluated by high resolution T1-weighted Images 12 hours, 24 hours, and 48 hours after $MnCl_2(1mol)$ Injection using 3D FSPGR (Fast Speiled Gradient Recalled echo) pulse sequence at 1.5T clinical MR scanner with high performance gradient system. Also, for quantitative evaluation, the signal-to-noise ratios of circular ROI on anatomical locations were measured. Results: The major structures on the optic nerve tract were enhanced after injecting $MnCl_2(1mol)$. The structures, which showed enhancement, were right optic nerve, optic chiasm, left optic tract, left lateral geniculate nucleus, left superior colliculus. The structures on the contralateral optic pathway to the right retina were enhanced whereas the structures on the ipsilateral pathway did not show enhancement. Conclusion: The Mn transport through axonal pathway of optic nerve sys)em was non- invasively observed after injecting injecting $MnCl_2$ at the retina, which is the end terminal of optic nerve system. This Mn transport seems to occur by voltage gated calcium $(Ca^{2+})$ channel and In case of direct Injection Into the retina, the fast transpori pathway of voltage gated calcium channel seems to be responsible for Mn transport.