• Korean Journal of Soil Science and Fertilizer
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• v.45 no.1
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• pp.98-102
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• 2012

Organic farming has rapidly increased in Gangwon province, but there is a concern about nutrient accumulation and nutrient imbalance in the soil of organic farming. This study was conducted to investigate the impact of continuous application of organic amendments on growth and yield of red pepper and soil characteristics compared with chemical fertilizers application for four years. Treatments of organic amendments including oil cake, rice straw compost, amino acid compost, rice bran compost, and mushroom media (spent substrate) compost resulted in comparable growth and yield of pepper to chemical fertilizers. Organic amendments improved soil physical and chemical characteristics. Especially, rice bran compost and oil cake significantly increased soil organic matter compared with chemical fertilizer application and mushroom media compost and rice straw compost significantly improved soil aggregate stability. On the other hand, available phosphate level in the soil amended with rice bran compost or mushroom media compost was relatively high compared with the other treatments due to relatively high phosphate levels in the composts. It is not easy to adjust nutrient composition in the organic materials. Therefore, the results obtained from the study imply that nutrient imbalance needs to be carefully considered in organic farming without use of chemical fertilizers.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.396-396
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• 2009

Chalcopyrite semiconductor $CuInSe_2$ nanoparticles were prepared using a low temperature colloidal route by reacting the starting materials (CuI, $InI_3$ and $Na_2Se$) in solvents. After synthesised $CuInSe_2$ nanoparticles precursors were mixed with organic binder for the viscosity of the precursor slurry to be suitable for the doctor blade method. The mixture of $CuInSe_2$ and binder was deposited onto molybdenum-coated sodalime glass substrates to form thin film. The precursor thin films were preheated on the hot plate to remove remaining solvents and binder material. After subsequent thermal processing of the thin film under a selenium ambient, $CuInSe_2$ absorber layer with grain size significantly lager than that of the nanoparticles was formed.

• Bulletin of the Korean Chemical Society
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• v.34 no.8
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• pp.2321-2324
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• 2013

An improved hybrid solar cell was obtained by focusing on the effects of ligand for CdSe nanoparticles, in the active layers. The performance was compared by mixing nanoparticles capped with pyridine or oleic acid for the acceptor material into poly(3-hexylthiophene):[6,6]-phenyl C61 butyric acid methyl ester based active layer. The solar cells with pyridine capped CdSe nanoparticles showed a power conversion efficiency of 2.96% while oleic acid capped CdSe nanoparticles showed 2.85%, under AM 1.5G illumination. Formation of percolation pathways for carrier transport and a reduction in the hopping event resulted in better performance of pyridine capped nanoparticles.

• Bulletin of the Korean Chemical Society
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• v.7 no.2
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• pp.129-136
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• 1986

The dipole moments for some coordination compounds with organic ligands have been calculated adopting the molecuar orbitals obtained from EHT calculation with modified technique. Adopting the molecular orbitals with the modified technique, the calculated dipole moments for all the coordination compounds with organic ligands give closer agreements with experimental values than those using the molecular orbitals obtained from EHT calculation. The calculated dipole moments suggest that $(C_2H_5)_2SO,\;(C_6H_5)_2SO,\;and\;(C_6H_5)_2SeO$ may have a trigonal planar structure and $(C_6H_5)_3AsO,\;and\;(C_6H_5)_3PBCl_3$ a square planar structure and $(C_2H_5)_2OZrCl_4$ may be distorted markedly. This work may also indicate that the modified technique is superior to the EHT calculation as far as the dipole moment calculation is concerned.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.5
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• pp.2527-2533
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• 2016

Sensitising cancer cells and at the same time desensitizing normal cells is a double task in cancer management. Agents which can combat the debilitating side effects of cancer therapeutics and simultaneously synergize with anticancer agents in specifically targeting cancer cells are needed. Selenium, a proven anticarcinogen, gains due importance in terms of its efficacy to combat the side effects of cancer therapy. This study is a comparative analysis of the chemoprotective effects of selenium compounds, methyl selenol (generated from organic selenomethionine (5mmol/L ; METase 40U/L)) and sodium selenite (inorganic form)($30{\mu}M$) in peripheral blood human lymphocytes exposed to cisplatin and mitomycin. Biochemical alterations occurring in many cells during apoptosis include loss of plasma membrane phospholipid asymmetry, DNA fragmentation, and activation of caspase-3. The present study demonstrated that the selenium metabolite and selenite are efficient in protecting lymphocytes undergoing DNA damage and exerted their activity by reducing caspase 3 expression. Interestingly organic methylselenol (MeSe) was found to offer more protective effects compared to inorganic selenite (SeL), by reducing the induction of apoptosis by the cytotoxic agents. This suggests that MeSe and to a lesser extent selenite might have potential for assessment in clinical trials and could be considered as strong candidates in pharmacogenomics or in the nutriprotective arena.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.3
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• pp.435-444
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• 2003

In 1957, Schwarz and Foltz discovered that selenium (Se) was an essential trace mineral and nutritionists then started extensive studies to figure out the metabolic function of this element which has been called as toxic mineral. The discovery that glutathione peroxidase (GSH-Px) contained Se demonstrated a biochemical role for Se as an essential trace element. The major physiological function of Se containing GSH-Px is thought to maintain low levels of $H_2O_2$ and other hydroperoxides in the cell to prevent tissues from peroxidation damages. It is known that the GSH-Px activity is increased when animals were fed high dietary levels of Se. Chemical properties of Se have much in common with sulfur (S) therefore Se would follow the sulfur pathways in its metabolism in animal body. Two sources of Se are available for supplementation of Se in animal feed. Inorganic Se can also exist in selenide (-2), elemental (0), selenite (+4) and selenate (+6) oxidation state with other minerals. When sulfur in S containing amino acids is replaced by Se, organic Se can be made and named "eleno"prior to the name of S containing amino acid, i.e. selenomethionine. Selenium deficiency affects humans as well as animals and dysfunctions such as exudative diathesis, retained placenta, mastitis, liver necrosis, Keshan disease, numerous diseases and cancer. From several centuries ago, Se toxicity was recognized in various animal species and much of the current toxic Se levels has been established largely based upon the controlled toxicity studies used inorganic Se. Toxic effects of Se in animal result in reduced feed intake, growth retardation, ataxia, diarrhea, alopecia and sloughing of hooves. However, several experiments demonstrated that Se deficiencies or toxicities were varied by dietary Se levels and sources. Recent studies demonstrated that the incidence of colorectal and prostate cancer was reduced by approximately 50% when humans consumed 200 ${\mu}g$ of Se daily.

• Journal of Mushroom
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• v.3 no.2
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• pp.79-84
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• 2005

The research for incubation period, mycelial density, day required for primordial formation after inoculation(below DPI), number of valid stipes, individual weight and accumulation amounts of organic selenium for P. cornucopiae by treating 100, 200, 300, 400, 500(${\mu}g/50g$) of $Na_2SeO_3$ is following. Incubation periods of P. cornucopiae are 20~23 days per each low concentration treatment with $Na_2SeO_3$. Compared to the control which took 22 days of incubation period, it is reduced 1 or 2 days. Mycelial density of P. cornucopiae treated with $Na_2SeO_3$ between 100 and $500{\mu}g/50g$ is very compact. DPI of P. cornucopiae treated with $Na_2SeO_3$ between 100 and $400{\mu}g/50g$ was reduced 1 or 2days, but $500{\mu}g/50g$ was increased 1 day. Number of valid stipes of P. cornucopiae treated with $Na_2SeO_3$ between 100 and $400{\mu}g/50g$ is between 19 and 20. It was increased 1 or 2, as compared to 18 of control, but $500{\mu}g/50g$ was reduced to 1. Individual weight of P. cornucopiae treated with $Na_2SeO_3$ between 100 and $400{\mu}g/50g$ was between 129 and 138g/850cc. It was increased 4.9~12.2% as compared to 123g/850cc of the control but $500{\mu}g/50g$ was 122g/50g. Accumulation amount of organic selenium for P. cornucopiae treated with $Na_2SeO_3$ between 100 and $500{\mu}g/50g$ was $2.73{\sim}8.19{\mu}g/g/dry$. It was increased 55~164 times as the concentration increased when compared to $0.05{\mu}g/g/dry$ of the control. In conclusion, incubation period, mycelial density, DPI, number of valid stipes, individual weight and accumulation amounts of organic selenium for P. cornucopiae by treating 100, ${\sim}400{\mu}g$ of $Na_2SeO_3$ was increased, but $500{\mu}g/50g$ was reduced. So more than $500{\mu}g/50g$ concentration treatments are required research.

• Journal of Mushroom
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• v.3 no.2
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• pp.85-89
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• 2005

The research for incubation period, mycelial density, day required for primordial formation after inoculation(below DPI), number of valid stipes, individual weight and accumulation amounts of organic selenium for P. cornucopiae by treating 600, 700, 800, 900, 1000(${\mu}g/50g$) of $Na_2SeO_3$ is following. Incubation periods of P. cornucopiae are 25~30 days per each treatment with $Na_2SeO_3$. Compared to the control which took 22 days of incubation period, it is increased 3 or 8 days for the treatment of $600{\sim}1000{\mu}g/50g$. Mycelial density of P. cornucopiae treated with $Na_2SeO_3$ between 600 and $1000{\mu}g/50g$ is very similar with control. DPI of P. cornucopiae treated with $Na_2SeO_3$ between 600 and $1000{\mu}g/50g$ was increased 3 or 8 days. Number of valid stipes of P. cornucopiae treated with $Na_2SeO_3$ between 600 and $1000{\mu}g/50g$ was between 10 and 16. It was decreased 2 or 8 as compared to 18 of control. Individual weight of P. cornucopiae treated with $Na_2SeO_3$ between 600 and $1000{\mu}g/50g$ was between 94 and 116g/850cc. It was decreased 5.7~23.5% as compared to 123g/850cc of the control. Accumulation amount of organic selenium for P. cornucopiae treated with $Na_2SeO_3$ between 600 and $1000{\mu}g/50g$ was $9.1{\sim}10.8{\mu}g/g/dry$. It was increased 182~216 times as the concentration increased when compared to $0.05{\mu}g/g/dry$ of the control. In conclusion, incubation period, mycelial density, DPI, number of valid stipes, individual weight and accumulation amounts of organic selenium for P. cornucopiae by treating $600{\sim}1000{\mu}g/g$ of $Na_2SeO_3$ was decreased. So that the optimal treatment was less $400{\mu}g/g$ than $600{\sim}1000{\mu}g/g$.

• Polymer(Korea)
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• v.36 no.4
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• pp.494-499
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• 2012

In this work, the effect of multi-walled carbon nanotube (MWCNT) on electromagnetic interference shielding effectiveness (EMI SE) and mechanical properties of MWCNT-reinforced polypropylene (PP) nanocomposites were investigated with varying MWCNT content from 1 to 10 wt%. Electric resistance was tested using a 4-point-probe electric resistivity tester. The EMI SE of the nanocomposites was evaluated by means of the reflection and adsorption methods. The mechanical properties of the nanocomposites were studied through the critical stress intensity factor ($K_{IC}$) measurement. The morphologies were observed by scanning electron microscopy (SEM). From the results, it was found that the EMI SE was enhanced with increasing MWCNT content, which played a key factor to determine the EMI SE. The $K_{IC}$ value was increased with increasing MWCNT content, whereas the value decreased above 5 wt% MWCNT content. This was probably considered that the MWCNT entangled with each other in PP due to an excess of MWCNT.

• Journal of Korea Foundry Society
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• v.42 no.4
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• pp.218-225
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• 2022

For hydrogen-vehicle applications (air pressure control valve housing, APCVH), an investigation was conducted to determine how micro-defects in a high- pressure die-casted Al alloy (industrial code: ALDC12) could be controlled by means of a post-treatment using an organic-based impregnation solution in order to improve the air- tightness of the die-casted Al sample. Two different impregnation solutions were proposed and its test results were compared to a imported product from Japan with respect to the processing variables used. A structural investigation of the components under study was conducted by means of computer tomography and 3D X-ray micro-CT. These observations revealed that the use of the impregnation treatment to seal micro-defects led to highly significant and beneficial changes which were attributed mainly to interconnections among inherent micro-pores. A leak test after impregnation revealed that the performance improvement rate of the die-casted Al sample was ~70% for INNO-01. Therefore, the developed impregnation solutions offer an effective strategy to control the micro-defects found in various vehicle parts via die-casting.