• Journal of The Korean Society of Grassland and Forage Science
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• v.24 no.1
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• pp.1-10
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• 2004

This pot experiment was conducted to investigate the effects of combined micronutrient application($T_1$;control, $T_2$; Fe, $T_3$; Fe＋Mn, $T_4$; Fe＋Mn＋Cu, $T_5$ ; Fe＋Mn＋Cu＋Zn, $T_6$ ; Fe＋Mn＋Cu＋Zn＋Mo, $T_7$ ; Fe＋Mn＋Cu＋Zn＋Mo＋B) on forage performance of pure and mixed cultures of orchardgrass and white clover. The third part was concerned with the changes in the contents and yields of N-compounds (crude/pure protein and soluble N-compounds) in forages. The results obtained are summarized as follows: 1. The contents of N-compounds(crude/pure protein and soluble N-compounds) were generally different according to the forage species, whether it was a pure or mixed culture, and additional fertilization, especially N. In orchardgrass, these contents were relatively low at the $T_3$ and $T_6$ in both pure and mixed cultures. In white clover, these contents were relatively decreased by the $T_1$, $T_3$, and $T_6$ in mixed culture. 2. The treatments influenced relatively more on the yields of crude/pure protein than on the dry matter yields of forages, and this tendency was more significant in white clover than in orchardgrass. 3. In white clover, the great differences in the yields of crude protein by the treatments occurred especially in mixed culture and at 5th cut without no additional fertilization. In white clover, the positive effects of optimum treatments on the yields of crude protein seemed to be decreased by the additional fertilization, especially N. In mixed culture, the favorable growth of white clover by the optimum treatments tended to be positively related to the favorable contents and yields of N-compounds. The changes in the yields of pure protein were similar to the tendency of crude protein

• Annals of Clinical Neurophysiology
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• v.8 no.1
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• pp.63-70
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• 2006

Background: Testosterone is reported to have neuroprotective effect in various neurological diseases. Recently, the mechanism involved in nitric oxide (NO)-mediated motor neuron death is under extensive investigation. The Cu/Zn-superoxide dismutase (SOD1) mutations has been implicated in selective motor neuron death of amyotrophic lateral sclerosis (ALS) and it is said to play an important role in NO-mediated motor neuron death. However, neuroprotective effect of testosterone on motor neuron exposed to NO has rarely been studied. Methods: Motor neuron-neuroblastoma hybrid cells expressing wild-type or mutant (G93A or A4V) SOD gene were treated with $200{\mu}M$ S-nitrosoglutathione. After 24 hr, cell viability was measured by MTT assay. To see the neuroprotective effect of testosterone, pretreatment with 1 nM testosterone was done 1 hr before S-nitroglutathione treatment. To study the mechanism of protective effect, $20{\mu}M$ flutamide (androgen receptor antagonist) was also pretreated with testosterone 1 hr before S-nitroglutathione treatment. Results: S-nitrosoglutathione showed significant neurotoxic effect in all three cell lines. Percentage of cell death was somewhat different in each cell line. 1 nM testosterone showed neuroprotective effect in G93A and wild-type cell line. In A4V cell line, testosterone did not showed neuroprotective effect. The neuroprotective effect of testosterone was reversed by $20{\mu}M$ flutamide. Conclusions: These results indicate that testosterone induces neuroprotection in NO-mediated motor neuron death directly through the androgen receptor. This neuroprotective effect of testosterone varies according to the types of SOD1 gene mutation. These data suggest that testosterone may be of therapeutic value against ALS.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.36 no.5
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• pp.531-535
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• 2023

Mechanoluminescence (ML) is a phenomenon where the application of mechanical force to ML materials generates an electric field and produces light, holding significant promise as an eco-friendly technology. However, challenges in commercializing ML technology has arisen due to its low brightness and short luminous lifetime. To address this, in this work, we enhance ML efficiency by mixing carbon nanotubes (CNTs) into a ZnS: Cu embedded in a polydimethylsiloxane composite ML device. The inclusion of CNTs boosts ML intensity by 98% compared to devices without CNTs, as the increasing CNT fraction elevates conductivity, thereby amplifying ML intensity. However, this increase in CNT fraction also leads to enhanced light absorption within the device. Consequently, we observe a trend where ML intensity rises initially but declines beyond a CNT fraction of 0.0015 wt%. Based on these findings, we anticipate that our research will make valuable contributions to the advancement of electrical powerless mechanoluminescent technology.

• Journal of the Korean Ceramic Society
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• v.51 no.5
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• pp.477-480
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• 2014

An $Al_2O_3$-CuO-ZnO (ACZ) precursor powder was synthesized by a facial sol-gel process using a nonionic surfactant span 80 as the chelating agent to improve the surface area and morphology. When creating a hydrogen membrane, several kinds of properties are required, such as easy dissociation of hydrogen molecules, fast hydrogen diffusion, high hydrogen solubility, and resistance to hydrogen embrittlement. ACZ-Ni composite membranes (cermet) were prepared with this precursor and pure Ni powder via the hot press sintering (HPS) method. The ACZ powder was characterized by XRD, BET, and FE-SEM. Hydrogen permeation experiments were performed by Sievert's type of hydrogen permeation membrane equipment. The hydrogen permeability of ACZ/Ni 10 wt% and ACZ/Ni 20 wt% was obtained as 7.2 and $10molm^{-2}s^{-1}$ at RT, respectively. These values of the corresponding membranes were slightly increased with increasing pressures.

• Journal of Conservation Science
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• v.33 no.3
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• pp.167-179
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• 2017

In this study, Sangpyeontongbo excavated at Bigyeongdo, Seosan, were investigated to determine the components of the corrosion products that were formed while they were buried underwater in an anaerobic environment. The causes of corrosion product formation were also determined. Microstructure observation, element mapping, principle component analysis for each year, and the detection of corrosion products were carried out. Results indicate that the concretions of corrosion products on the surface are needle-, hexahedral-, and octahedral-shaped; Pb, Cu, and S were among the elements detected. The Cu-S layer was clearly verified using element mapping. An analysis of major elements for each layer showed that Cu, S, and Pb were present and that most Zn was eliminated. The corrosion products detected were $PbCO_3$ (concretion) and $Cu_{1.96}S$ (metal). Accordingly, the anaerobic corrosion properties of Sangpyeongtongbo are summarized as follows: dezincification, copper sulfide, and lead compound.

• The Korean Journal of Ecology
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• v.18 no.3
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• pp.419-427
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• 1995

This study was carried out to investigate the concentrations of Cu, Pb, Zn and in seawater, sediments and Mytilus edulis at Masan Bay, Onsan Bay, Daesan industrial complex and unpolluted area for the degree of contamination on the coast of Korea. The concentrations of dissolved Cu, Pb, Zn and Cd in seawater the ranges of 0.29~0.79 ${\mu}g/l$, 0.03~0.08 ${\mu}g/l$, 0.19~2.01 ${\mu}g/l$ and 0.01~0.05 ${\mu}g/l$, respectively. The concentrations of Pb(p<0.001) and Zn(p<0.01) showed the significant differences between the contaminated and unpolluted area. There were the ranges of 13~55 ${\mu}g/l$, 26~101 ${\mu}g/l$, 51~263 ${\mu}g/l$ and 0.8~2.2 ${\mu}g/l$ in the concentration of Cu, Pb, Zn and contaminated and unpolluted area. The concentration of Cu, Pb, Zn and Cd in the Mytilus edulis showed the ranges of 0.69~2.77 ${\mu}g/l$, 0.29~1.50 ${\mu}g/l$, 13.57~52.90 ${\mu}g/l$ and 0.09~0.85 ${\mu}g/l$ respectively. These concentrations of four trace metal in Mytilus edulis were not significantly different with sites. Trace metal contents of Mytilus edulis in the contaminated site were similar to those in the unpolluted area. This is thought that metal concentration in coastal seawater were not relatively serious.

• 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 $0.015%\;CuSO_4{\cdot}5H_2O$, $0.030%ZnSO_4{\cdot}7H_2O$).

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.218-218
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• 2011

The CIGS Solar Cells have the highest conversion efficiency in the film-type solar cells. They consist of p-type CuInSe2 film and n-type ZnO film. The CdS films are used as buffer layer in the CIGS solar cells since remarkable difference in the lattice constant and energy band gap of two films. The CdS films are toxic and make harmful circumstances. The CdS films deposition process need wet process. In this works, we design and make the hitter and lamp reflection part in the sputtering system for the ZnS films deposition as buffer layer, not using wet process. Film thickness, SEM, and AFM are measured for the uniformity valuation of the ZnS films. We conclude the optimum deposition temperature for the films uniformity less than 1.6%. The ZnS films deposited by the sputtering system are more dense and uniform than the CdS films deposited by the Chemical Bath Deposition Method(CBD) for the CIGS Solar Cells.

• Economic and Environmental Geology
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• v.38 no.2 s.171
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• pp.135-142
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• 2005

In order to investigate the contamination level and seasonal variation of heavy metals and evaluate the bioavailability of toxic elements, environmental geochemical survey was undertaken at the Dogok Au-Ag-Cu mine area. The main pollution sources in the area were suggested as tailings, mine waste materials and mine water. Elevated levels of $140{\cal}mg/{\cal}kg{\;}As,{\;}107{\cal}mg/{\cal}kg{\;}Cd,{\;} 3017{\cal}mg/{\cal}kg{\;}Cu,{\;}12926{\cal}mg/{\cal}kg{\;}Pb,{\;}9094{\cal}mg/{\cal}kg$ Zn(before rainy season) were found in mine tailings. Concentrations of heavy metals in farmland soils exceeded normal level in nature soil (Bowen, 1979). The highest level of heavy metals was found in water samples near the mine tailing dumps regarded as a main pollution source of toxic elements in the area. These concentrations decreased to downstream due to the effect of dilution. From the results of sequential extraction analyses for tailings and soils, non-residual forms of heavy metals were found, which indicate the contamination to be progressing by continuing weathering and oxidation. Cadmium and Zn would be of the highest mobility in all samples. The bioavailability of Cd, Cu, Zn and As using SBET analysis from paddy soils was $53.3{\%},{\;}46.5{\%},{\;}41.0{\%}$ and $37.0\%$, respectively. The farmland soil sample(S3) showed the highest total concentration and bioavailability of heavy metals.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.11a
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• pp.180-180
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• 2009

나노 형광체 합성에 있어서 입자 형상 및 입자 크기의 변화를 알아보기 위해 녹색 발광하는 ZnS:Cu 형광체를 액상반응법으로 합성하였다. X선 회절 분석기로 결정성을 확인하였으며, 전계 방사 주사 전자 현미경 (FE-SEM)을 통해 각각 30~80 nm 이하 크기임을 확인하였다. 녹색발광을 하며, 450 $^{\circ}C$부터 900 $^{\circ}C$ 까지 온도 상승함에 따라 결정성이 증가 하였으며, hexagonal구조에서 가장 효율이 높은 PL 값을 보였다.