• Journal of the Korean Vacuum Society
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• v.21 no.5
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• pp.233-241
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• 2012

We have deposited the bilayer consisted of the underlayer and the overlayer by using DC magnetron sputter on Single crystal MgO (001) substrate. This bilayer was fabricated at fixed annealing temperature and time. We have controlled agglomeration effect by changing of the bilayer thickness. Finally, we have made the self-organization and nano-structured film. In this processing, we have made nano-dot which consists of the underlayer and the overlayer, unlike the existing method called the agglomeration effect in the single layer. The underlayer has deposited using Ti, Cr and Co. And the overlayer has deposited with Ag. Through the analysis of Atomic force microscopy (AFM), the microstructure of underlayer is observed by AFM to confirm the formation of nano-dot. As the nano-dot through above processing, we have found that the nano-dot has the different shape. As a result, when we manufactured nano-dot through the agglomeration effect of bi-layer, the best matching material is Ti for underlayer. And also, we have found that MgO/Ti/Ag samples have been grown expitaxially toward the direction of MgO (001) by X-ray Diffraction analysis.

• Journal of Animal Environmental Science
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• v.18 no.3
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• pp.201-206
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• 2012

Horse manure general composition and contaminants, heavy metals content analysis was investigated as follows. The moisture content of horse feces was 76.1% and 96% for horse urine. The average T-N, T-P, T-K concentrations of the racing horse were 0.18%, 0.10%, 0.22% respectively and 2.88%, 0.0015%, 0.84% for urine. And the average BODs, COD, SS concentrations were 26,906 $mg/{\ell}$, 36,642 $mg/{\ell}$, 89,375 $mg/{\ell}$ respectively and 14,298 $mg/{\ell}$, 7,484 $mg/{\ell}$, 6,987 $mg/{\ell}$ for urine. In addition, the Cr, Cu, Ni, Cd, Pb, Zn concentrations of feces were 2.65 mg/kg, 7.05 mg/kg, 1.24 mg/kg, 0.07 mg/kg, 0.01 mg/kg, 45.11 mg/kg respectively and 1.52 mg/kg, 1.62 mg/kg, 0.00 mg/kg, 0.03 mg/kg, 0.03 mg/kg, 4.49 mg/kg for urine on the fresh matter basis. The end of the survey was that the quality of the compost can be used as a raw material, and manure is necessary to constantly driven forward horse manure composting research.

• Korean Journal of Crystallography
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• v.8 no.1
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• pp.48-58
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• 1997

[ $CuInTe_2$ ] synthesised in a horizontal electric furnace was found to be polycrystalline. Single crystals of $CuInTe_2$ were grown with the vertical Bridgman technique. The photoconductivity and photoluminescence of the crystals were measured in the temperature range 20 to 293 K. From the photocurrent peaks measured for the samples both perpendicular and parallel to c-axis, the energy band gaps of the samples were found to be 0.948 eV and 0.952 eV at room temperature respectively. The energy difference of the photocurrent and photoluminescence peaks of the samples both perpendicular and parallel to the c-axis measured at room temperature was a phonon energy, and its values were 22.12 meV and 21.4 meV respectively. The splitting of the valence band due to spin-orbit and crystal field interaction was calculated from the photocurrent spectra of the samples, The ${\Delta}cr\;and\;{\Delta}so$ are 0.046,0.014 eV respectively.

• Analytical Science and Technology
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• v.7 no.3
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• pp.387-393
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• 1994

Quantitative analytical conditions for chromium using solvent extraction followed by atomic absorption spectrometry was studied. Trioctylamine(TOA) in tertiary amine or Trioctylmethylammoniumchloride(TOMAC) in quaternary ammonium salt, both containing octyl group was used as an anion exchangers. Absorbance were measured for the different kinds of acid added and as changing the concentration of acid by graphite furnace atomic absorption spectrometer. The maximum absorbance was obtained at the concentrations of HCl, 0.1M to 0.3M for TOA and 0.03M to 0.1M for TOMAC. Mole ratios over 1:1 of TOA or TOMAC dissolved in MIBK solution to chromium in sample shows optimum extraction efficiency while HCl was added to the MIBK. As a result of scrutinizing the extraction process, the methods employed in this experiment turned out to be better extraction efficiency for chromium, compared to similar extraction methods.

• Journal of the Korean Society for Heat Treatment
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• v.18 no.6
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• pp.369-374
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• 2005

Nitrogen ion implantation in Nimonic 80A using plasma immersion ion implantation (PIII) was investigated at a pulse voltage of -60 kV and ion dose of $3{\times}10^{17}{\sharp}/cm^2$, $6{\times}10^{17}{\sharp}/cm^2$, $12{\times}10^{17}{\sharp}/cm^2$. PIII is an effective technology to improve the surface hardness and wear resistance of materials. And also this technology is not limited by the shape and size of materials. PIII would be a promising technique in the future. Surface hardness and wear resistance of the $N^+$ ion implanted Nimonic 80A were increased with the increase in the incident ion dose. The surface hardness of the untreated Nimonic 80A is 420 Hv, the hardness of implanted Nimonic 80A is 1050 Hv at $N^+$ ion dose of $12{\times}10^{17}{\sharp}/cm^2$. The wear loss of the untreated is 82.5 mg, the wear loss of the implanted is 0.004g at $N^+$ ion dose of $12{\times}10^{17}{\sharp}/cm^2$. The $Cr_2N$ is detected on the surface of the implanted Nimonic 80A by XRD analysis.

• Journal of the Korean institute of surface engineering
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• v.40 no.4
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• pp.175-179
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• 2007

An Fe-Ni-Co based superalloy Incoloy 909 (Incoloy 909) has been used for gas turbine engine component material. This alloy is susceptible to high temperature oxidation and corrosion because of the absence of corrosion resistant Cr. For the improvement of durability of the component of Incoloy 909 aluminizing-chromate coating by pack cementation process has been investigated at relatively low temperature of about $550^{\circ}C$ to protect the surface microstructure and properties of Incoloy 909 substrate. As a previous study to aluminizing-chromate coating by pack cementation of Incoloy 909, the optimal aluminizing process has been investigated. The size effects of source Al powder and inert filler $Al_O_3$ powder and activator selection have been studied. And the dependence of coating growth rate on aluminizing temperature and time has also been studied. The optimal aluminizing process for the coating growth rate is that the mixing ratio of source Al powder, activator $NH_4Cl$ and filler $Al_O_3$ are 80%, 1% and 19% respectively at aluminizing temperature $552^{\circ}C$ and time 20 hours.

• Journal of the Korean Society of Radiology
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• v.3 no.2
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• pp.27-31
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• 2009

Now a days, the Medical X-ray equipments has become digitalized from analog type such as film, cassette to CR, DR. And many scientists are still researching and developing the Medical X-ray equipment. In this study, we used the Bismuth tri-iodide to conversion material for digital X-ray equipments and we couldn't get the satisfying result than previous study, but it opened new possibility to cover the disadvantage of a-Se is high voltage aplly and difficultness of make. In this paper, we use $BiI_3$ powder(99.99%) as x-ray conversion material and make films that have thickness of 200um and the film size is $3cm{\times}3cm$. Also, we deposited an ITO(Indium Tin Oxide) electrode as top electrode and bottom electrode using a Magnetron Sputtering System. To evaluate a characteristics of the produced films, an electrical and structural properties are performed. Through a SEM analysis, we confirmed a surface and component part. And to analyze the electrical properties, darkcurrent, sensitivity and SNR(Signal to Noise Ratio) are measured. Darkcurrent is $1.6nA/cm^2$ and sensitivity is $0.629nC/cm^2$ and this study shows that the electrical properties of x-ray conversion material that made by screen printing method are similar to PVD method or better than that. This results suggest that $BiI_3$ is suitable for a replacement of a-Se because of the reduced manufacture processing and improved yield.

• Journal of Embryo Transfer
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• v.10 no.2
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• pp.163-169
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• 1995

In the experiment I for maas production of bovine early embryos, 18~20hpi fertilized eggs (756 eggs) and parthenogenic eggs (618 eggs) which were treated by 10% ethanol were cultured in both TGM and CZB. In the experiment II, suppiment effects each in CZB and CRlaa were tested by matured and fertilized oocytes which were after 18~20hpi. In the case of experiment I after 48hr, the cleavage rates of normally fertilized eggs were 66.6% in TCM treatment and 77.7% in CZB treatment, and after 240h the blastocysts were 7.5% in TCM and 14.1% in CZB. In the parthenogenic eggs, the deavage rates at 48hr were 39.6% in TCM and 57.5% in CZB, and at 240h, the blastocysts were 0.9% in TCM and 4.4% in CZB. These results showed that the effects of CZB on developmental ability to parthenogenic eggs as well as nomally fertilized eggs are relatively high. In experiment W, the effect of exposing the cleaved embryos to CZB for 30h on the blastocyst formation was examined. Similar rates of blastocyst formation were obtained both in TCM and CZB, suggesting that CZB exposure. during ealry development is critical. In experiments III ~ V, the effects of supplements were examined. The cleavage rates of CZB treatments at 48h were 83.8% in control, 78.1% in BSA+A.A+SIT, 75% in 5% FCS+A. A+SIT, 88.6% in BSA+A.A+SIT and not co-cultured BSA+A.A+SIT had 85.7% and in the case of 240h blastocysts showed 22.6, 0.0, fl.1, 6.5 and 0%, respectively. As a result, this study showed that CZB was effective culture system for in vitro development, and that CZB and CR$_1$aa had no significant differences and effects between them. It may be concluded that in the simple media containing supplements could replace the co-culture systems of bovine early embryo development.

• Economic and Environmental Geology
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• v.2 no.4
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• pp.23-71
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• 1969

Sediment samples were taken at about half-mile intervals from all the inajor rivers draining the St. Austell granite mass. The minus 80 mesh(B.S.S.) fraction of each sample was analysed, using semiquantitative methods, for sodium, potassium, lithium, phosphorus, nickel, chromium, tin, tungsten, arsenic copper, zinc and lead. The work was carried out with the view to gaining further information as to the geographical distribution of such different granite facies as might axist, and to investigate the geochemical dispersion of these elements with relation to mineralisation in this area. The sesults confirm Exley's suggestion that the mass consists of two major granite intrusions, the earlier undifferentiated one is joined on the west by a later differentiated intrutive. During the work grid deviation maps proved particularly useful in obtaining data concerning the nature of the granite but frequency diagrams were not particularly helpful. All the known lode areas were associated with stream sediments containing anomalously high concentrations of lode metals and it is concluded that these high concentrations are due premarily to lode material transferred to the streams in the form of tailings lost during milling operations.

• Korean Journal of Animal Reproduction
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• v.25 no.1
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• pp.51-61
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• 2001

This study was conducted to determine developmental ability of reconstructed embryos by nuclear transfer using somatic cell of Korean bull with high genetic value. Fibroblast cells obtained from ear biopsy of the bull were cultured in Dulbecco's Modified Eagle's medium (DMEM) at 37$^{\circ}C$ in air containing 5% $CO_2$. The cummulus-oocyte complexes were collected from slaughterhouse and were matured in vitro for 20 h in TCM 199 culture medium and the oocytes were then enucleated in modified phosphate buffered saline with cytochalasin B. Matured bovine oocytes were enucleated by aspirating the first polar body and metaphase chromatin using a beveled pipette in modified phosphate buffered saline. The ear fibroblast cells were fused into enucleated oocyte by electrical stimulation. The reconstructed oocytes were activated with ionomycine and 6-dimethylaminopurine, and then cultured in CR1aa medium for 7.5 days. Out of 524 bovine eggs reconstructed by nuclear transfer 65.6%(277/422) embryos were cleaved, and 30.7% (85/277) cleaved embryos were developed to the morula to blastocysts. There was no difference of developmental ability in vitro of reconstructed embryos regardless of donor cell passages. In order to determine fate of foreign mitochondria of donor nucleus, the Mito Tracker stained cells were fused into enucleated oocytes. The donor mitochondria were detected early stage of embryos, but disappeared rapidly. The developmental ability of reconstructed embryos was not impaired by Mito Tracker treatments. The results indicate that viable reconstructed embryos can be producted by nuclear transfer using somatic cell of Korean bulls.bulls.