• Korean Journal of Ecology and Environment
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• v.41 no.2
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• pp.128-136
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• 2008

An attempt was made in the Veeranam freshwater lake with the objectives to collect, identify, describe and document the algae occurring from March 2007 to August 2007. Qualitative and quantitative characterization of phytoplankton and analysis of physico-chemical parameters of water samples were carried out at monthly intervals during the study period in the western and eastern sides of the lake. It was found that the phytoplankton community embraced 68 genera belonging to four classes viz., Bacillariophyceae (40), Chlorophyceae (22), Cynophyceae (4) and Euglenophyceae (2). There were significant influences of various physico-chemical parameters on the phytoplankton population density. Commonly occurred genera, Oscillatoria (Cyanophyceae), Navicula (Bacillariophyceae) and Scenedesmus (Chlorophyceae), were subjected to energy dispersive spectroscopic analysis (EDS). They were found to accumulate different elements such as Zn, P, S, Ca, Mg, Fe, N, Si, Cl and Mn. Among these the member Cyanophyceae contained Zn, P, Mg, Ca, Mn, S and N. Bacillariophyceae Si, Zn, Mg, Cl, N, Fe, and Ca. Chlorophyceae Ca, Mg, N, Fe, Cl, Zn, Si and Mn. Thus these observations would determine the chemical dialogue between the cell structures and role of the elements. Further, it gives the clue about the phytoplankton growth requirements.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07b
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• pp.980-983
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• 2003

The preparation of ZnS:Mn,Cl phosphor has been carried out by combustion method. Manganese nitrate was decomposed with an organic fuel at $500^{\circ}C$ to give fine sized crystallites in presence of alkali metal halides at a lower temperature than the conventional synthesis. The phosphors thus obtained were then heated at 900 to $1200^{\circ}C$ in an inert atmosphere, for 3hours to get better luminescent properties. The phosphors were prepared at different temperatures and at different doping concentrations of manganese to determine the optimal conditions for synthesizing the phosphors with superior optical properties. Scanning electron microscopy (SEM) investigations have been carried out to observe the particle morphology and the grain size. Powder X-ray diffraction(XRD) was also performed to characterize the phosphors.

• 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.

• Electrical & Electronic Materials
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• v.10 no.3
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• pp.262-267
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• 1997

In order to improve the brightness and chromaticity of green emitting low voltage phosphor for FED, we examine PL, PLE and CL emission characteristics of ZnGa$_{2}$O$_{4}$:Mn,O prepared in Ar and vacuum. ZnGa$_{2}$O$_{4}$:Mn,O sintered in vacuum shows about 16 times as bright as the one fabricated in Ar and excellent chromaticity. In PL emission spectra of ZnGa$_{2}$O$_{4}$:Mn,O at low temperature of 9 K, two peaks are observed at 504 nm and 513 nm. At room temperature, the two peaks are superimposed due to the lattice thermal vibrational energy, and only one peak is observed at 509 nm. From PLE measurements, it is believed that the energy levels of the host lattice and Mn ions are coexisted. The energy transfer from the host lattice to the emission center of Mn$^{2+}$ ions occurs.s.

• 전기의세계
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• v.38 no.10
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• pp.13-22
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• 1989

본 연구에서는 EL에 사용되고 있는 분말형광체에 대한 물리적 제현상을 소개하고 아울러 본 연구실에서 연구해 온 ZnS : Mn, Zns : TbF$_{3}$, Zns : SmF$_{3}$, CaS : EuCl$_{3}$, SrS: CeCl$_{3}$ 형광체 및 박막EL 소자에 관한 실험과 내용을 바탕으로 형광체의 특성을 종합 분석하고 현상을 고찰, 검토하고자 한다.

• Applied Biological Chemistry
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• v.6
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• pp.57-59
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• 1965

According to the result of the observations on the effect of the reagents, $CuSO_4{\cdot}5H_2O$, $ZnSO_4{\cdot}7H_2O$ $MnSO_4{\cdot}4H_2O$, $HgCl_2$, upon the mycelial growth of psalliota campestris $HgCl_2$ showed the strongest effect on checking the mycelial growth $(,.008{\sim}0.01%)$ $CuSO_4{\cdot}5H_2O(0.030%)$, $ZnSO_4{\cdot}7H_2O(0.080%)$, came next and the $MnSO_4{\cdot}4H_2O(0.100%)$ was the weakest. Writer also found that showed the promoting effect of the mycelial growth in appropriate Concentration (at $0.015%\;CuSO_4{\cdot}5H_2O$, $0.030%ZnSO_4{\cdot}7H_2O$).

• Journal of Environmental Science International
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• v.4 no.5
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• pp.103-103
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• 1995

In the Chinhae Bay, Korea, sedimentation rates and sedimentary record of anthropogenic metal loads were determined by $^{210}Pb$ dating and heavy metal analysis of four sediment cores . The sedimentation rates varied from 0.16g/$cm^2$/yr(3.1mm/yr) at Sta. Ct, located within narrow waterway to 0.24g/$cm^2$/yr(4.8mm/yr) at Sta. Cl, located in Haengam Bay. Maximum contents of Mn, Zn, Cu and Cr were observed at Sta. C2 located near the mouth of Masan Bay, while minimum contents were observed at Sta. CB. Mn/Fe ratios at Sta. C2 and Sta. C4 showed gradually increasing and decreasing downward, respectively, in the upper layer of sediment cores. This suggests that Mn may be diagenetically redistributed in highly reduced environment. At Sta. C2, the concentrations of Zn and Cu began to increase from 1920s by anthropogenic input and have been remarkablely increasing since mid 1960s. At Sta. C3, located near Sungpo, anthropogenic input of these two elements has also slightly increased after 1970s. However, pollution of these two elements was not significant in Haengam Bay(Sta. Cl) and Chiljun watenway(Sta. C4). The pollution of Co, Ni and Cr was not remarkable in all core samples except surface sediment of Sta. C2. The total input of anthropogenic Zn and Cu since 1920s was estimated to be 28∼792 ㎍/cm2 and 0∼168㎍/cm2, respectively. Sta. C2 showed remarkablely higher values relative to other stations: anthropogenic loads of Zn and Cu constituted 27% and 29% of the total sedimentary inventories at the present day, respectively. Fe, Ni, Cr and Co contents showed good correlation(r>0.8) with each other. Anthropogenic Zn and Cu also showed a very good positive correlation(>0.9). However, correlation between these two group of element was quite scattered, indicating different sources and geochemical behaviors.

• Journal of Environmental Science International
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• v.4 no.5
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• pp.489-500
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• 1995

In the Chinhae Bay, Korea, sedimentation rates and sedimentary record of anthropogenic metal loads were determined by $^{210}Pb$ dating and heavy metal analysis of four sediment cores . The sedimentation rates varied from 0.16g/$cm^2$/yr(3.1mm/yr) at Sta. Ct, located within narrow waterway to 0.24g/$cm^2$/yr(4.8mm/yr) at Sta. Cl, located in Haengam Bay. Maximum contents of Mn, Zn, Cu and Cr were observed at Sta. C2 located near the mouth of Masan Bay, while minimum contents were observed at Sta. CB. Mn/Fe ratios at Sta. C2 and Sta. C4 showed gradually increasing and decreasing downward, respectively, in the upper layer of sediment cores. This suggests that Mn may be diagenetically redistributed in highly reduced environment. At Sta. C2, the concentrations of Zn and Cu began to increase from 1920s by anthropogenic input and have been remarkablely increasing since mid 1960s. At Sta. C3, located near Sungpo, anthropogenic input of these two elements has also slightly increased after 1970s. However, pollution of these two elements was not significant in Haengam Bay(Sta. Cl) and Chiljun watenway(Sta. C4). The pollution of Co, Ni and Cr was not remarkable in all core samples except surface sediment of Sta. C2. The total input of anthropogenic Zn and Cu since 1920s was estimated to be 28~792 $\mu\textrm{g}$/cm2 and 0~168$\mu\textrm{g}$/cm2, respectively. Sta. C2 showed remarkablely higher values relative to other stations: anthropogenic loads of Zn and Cu constituted 27% and 29% of the total sedimentary inventories at the present day, respectively. Fe, Ni, Cr and Co contents showed good correlation(r>0.8) with each other. Anthropogenic Zn and Cu also showed a very good positive correlation(>0.9). However, correlation between these two group of element was quite scattered, indicating different sources and geochemical behaviors.

• Journal of the Korean earth science society
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• v.27 no.3
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• pp.313-327
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• 2006

This study investigated the geochernical characteristics of Mn scale formed in groundwater wells at the Damyang area. The composition of Mn scale consists mainly of MnO and $SiO_2$. The content of Mn ranges from56.61wt.% to 68.69wt.%, and $SiO_2$ content ranges from 1.56wt.% to 10.45wt.%. The contents of Mo and Ba in Mn scale increased with increased depth; whereas, the content of Zn and Pb decreased with increased depth. Birnessite, quartz and feldspars were identified in Mn scales using x-ray powder diffraction studies. The IR absorption bands for Mn scales show major absorption band due to OH stretching, adsorbed molecular water, and birnessite stretching, respectively. In the SEM and EDS analysis, the Mn scale consists of botryoidal, spherical, spherulite, and empty straw structure. Those structure may be precipitated simply due to oversaturation with concentrated Mn content or may be formed through biogenic precipitation by Lepthothrix discophora. Under microanalysis using EDS on those structure surface of Mn scales, the Mn atomic percent range from 28 to 44, and such elements revealed the presence of Si, K, Na, Ca, Cl, Cu, Zn, and Ba.

• Korean Journal of Food Science and Technology
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• v.44 no.4
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• pp.484-487
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• 2012

A discrimination technique for domestic and imported Scutellaria baicalensis was developed using an energy dispersive X-ray fluorescence spectrometer (ED-XRF). Mineral content ratios, of a total of 43 species, including P, S, Cl, K, Ca, Mn, Fe, Cu, and Zn, were measured among 204 samples. Macro element content ratios and trace element content ratios were determined using the standardless fundamental parameters (SLFP) analysis. Inorganic element ratios of P, S, K, Ca, Cl, Mn, and Fe were significantly different between domestic and imported samples. The result from the canonical discriminant analysis showed that the accuracy of geographical origin discrimination was 95.15%; the correlation coefficient was 0.888. It was concluded that this technique could be used as a useful method in discriminating the geographical origins between domestic and imported Scutellaria baicalensis.