• Elastomers and Composites
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• v.31 no.2
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• pp.111-121
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• 1996

The characteristic of silicone rubber can be seen from its resistance to both low and high temperature, whereas HNBR is resistant only in high temperature moderatly although it can be compounded to give good tensile properties, good oil resistance while silicone rubber severely lacks in these qualities. This study was initiated a balance of properties by blending HNBR and silicone rubber which is not considered for commercial blending; blends of HNBR with silicone rubber tend to show immiscible due to dissimilar nature of silicone and HNBR, the possibility of phase separation cannot be ruled out, in unfilled system after vulcanisation leading to premature failure. Attempt has been made to improve compatibility and minimise the layer seperation by the use of compatibilizer. Both filled and unfilled systems, in presence and absence of compatibilizer have been studied. Improvement in tensile properties of the blends or are observed as compared to the non-blended rubber. Different ratios of HNBR and silicone rubber are represented in this study. Blends of HNBR with silicone rubber were immiscible system. The tensile strength increased with filler loading.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.2
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• pp.445-450
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• 2016

This paper studied on the influence of naval vessel shape on vertical magnetic field after the vessel was demagnetized. The triangular shape, the rectangular shape and circular shape were adaped from vessel's structual drawings. Magneto-static FEM analysis was performed to obtain the iduced magnetic field due to earth magnetic field for those shapes. During demagnetization process, magnetic field of residual magnetization was observed. The holizontal and vertical magnetic field were calculated depending on vertical bias magnetic field through magnetc component seperation. To demagnetize naval vessel ship, demagnetizing coils shoud be wound more finely in the vow and stern of the ship than it should be in the mid-part of the ship.

• Archives of Pharmacal Research
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• v.27 no.10
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• pp.1009-1015
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• 2004

Quantitative Structure-Resolution Relationship (QSRR) using the Comparative Molecular Field Analysis (CoMFA) software was applied to predict the chromatographic behaviors of chiral drugs with an amine moiety on the chiral cellobiohydrolase (CBH) columns. As a result of the Quantitative CoMFA-Resolution Relationship study, using the partial least square method, prediction of the behavior of drugs with amine moiety upon chiral separation became possible from their three dimensional molecular structures. When a mixed mobile phase of 10 mM aqueous phosphate buffer (pH 7.0) - isopropanol (95 : 5) was employed, the best Quantitative CoMFA-Resolution Relationship, derived from the study, provided a cross-validated $q^2$ = 0.933, a normal $r^2$ = 0.995, while the best Quantitative CoMFA-Separation Factor Relationship, also derived from the study, yielded a cross-validated $q^2$ = 0.939, a normal $r^2$ = 0.991. When all of these results are considered, this QSRR-CoMFA analysis appears to be a very useful tool for the preliminary prediction on the chromatographic behaviors of drugs with an amine moiety inside chiral CBH columns.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.2A
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• pp.98-106
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• 2005

We propose a new wireless fair queueing algorithm, WFQ-R (Wireless Fair Queueing with Retransmission), which is well matched with the LLR (Link Level Retransmission) algorithm and does not require channel prediction. In the WFQ-R algorithm, the share consumed by retransmission is regarded as a debt of the retransmitted flow to the other flows. Thus, the WFQ-R algorithm achieves wireless fairness with the LLR algorithm by penalizing flows that use wireless resources without permission under the MAC layer. Through simulations, we showed that our WFQ-R algorithm maintains fairness adaptively and maximizes system throughput. Furthermore, our WFQ-R algorithm is able to achieve flow separation and compensation.

• Journal of Powder Materials
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• v.14 no.4
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• pp.256-260
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• 2007

The surface of magnetite ($Fe_{3}O_{4}$) nanoparticles prepared by coprecipitation method was modified by carboxylic acid group of poly(3-thiophenacetic acid (3TA)) and meso-2,3-dimercaptosuccinic acid (DMSA). Then the lysozyme protein was immobilized on the carboxylic acid group of the modification of the magnetite nanoparticles. The magnetite nanoparticles are spherical and the particle size is approximately 10 nm. We measured quantitative dispersion state by dispersion stability analyzer for each $Fe_{3}O_{4}$ nanoparticles with and without surface modification. The concentration of lysozyme on the modified magnetite nanoparticles was also investigated by a UV-Vis spectrometer and compared to that of magnetite nanoparticles without surface modification. The functionalized magnetite particles had higher enzymatic capacity and dispersion stability than non-functionalized magnetite nanoparticles.

• Resources Recycling
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• v.3 no.1
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• pp.44-51
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• 1994

PET bottles were composed of several different materials such as PET, HDPE, PVC and PP, it is necessary for recycling of PET bottles to precede seperation of each material. This study is purposed of recycling of PET bottles by separation using float and sink method. Pure PET is obtained a proportion of 94% on condition that bottle labels were removed by using tap water. In case the labels were attached on the bottles, PET was unable to obtain because of PVC and PET sink, and PP and HDPE float. Therefore, the labels should be removed before separation of PVC lebels substituted for PP or PE material. The various physical properties of recovered PET and HDPE were measured and compared with the original PET and HDPE, and it is identified that recycling is possible as a result.

• Korean Journal of Veterinary Research
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• v.35 no.3
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• pp.553-562
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• 1995

To elucidate pathologic change of skin in porcine exudative epidermitis, immunohistochemical and electron microscopical observations were carried out in the skin of the suckling pigs inoculated with Staphylococcus hyicus subsp hyicus which were isolated from natural case. In immunohistochemistry, ATPase-positive dendritic cells were more populated in epidermo-dermal junctional areas and perivascular area in dermis than in epidermal area as the disease was proceeded. These dendritic cells were identified as Langerhans cell by immunoperoxidase staining and these cells were populated granulomatous bodies. Electron microscopical study showed various retrogressive degeneration and vacuolation of epidermal cell organelles with retention of amorphorous exudates in intercellular space, and cellular seperation. Langerhans cells present in intercellular space of epidermis were populated in epidermo-dermal junctional areas, in dermis, and around granulomatous bodies. Langerhans cells contained decreased Birbeck granules in number but increased lysosome and ribosome. These cells were in contact with lymphocytes. This study was discussed relation between the various immunocytes and the formation of granulomatous bodies, and this inflammation was considered as delayed type hypersensitivity.

• Journal of the Korean Society of Marine Environment & Safety
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• v.12 no.2 s.25
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• pp.133-137
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• 2006

In adjacent sea areas of Yeosu, there are many crossing traffics between eastbound and westbound vessels. Traffic congestion is increasing in sea area of east Sori island and near Yokji Island. In this research, we established TSS near Yeokmando Areas and new recommended route which connected to Seopdo west recommended route to reduce meeting traffic between eastbound vessels and westbound vessels.

• Journal of Nutrition and Health
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• v.24 no.3
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• pp.199-205
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• 1991

Retinoic acid. the active metabolite of vitamin A. was detected in the human liver for the first time using a new method. A rapid and sensitive technique has been developed using gradient-elution. reverse-phase high performance liquid chromatography. This assay. with simultaneous multiwavelength detection at 294nm, 325nm and 450nm after saponifcation of liver samples. allows us seperation and quantitation of vitamin E, retinoic acid, total retinoids and various carotenoids in one small sample. The proportion of retinoic acid to total retinoids in human liver appears to be quite $consistent(2.4\pm0.2%$ ). With low vitamin A storage in liver, detection at another wavelenth 354nm would increase the sensitivity for retinoic acid of small quantity This method of analysis could be used for other tissues like red blood cells, plasma or serum, also. Hepatic retinoic acid level with total retinoids and carotenoids would serve a better indicator of functional vitamin A nutriture especially for those with disease requiring needle biopsy of liver.

• Journal of Sasang Constitutional Medicine
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• v.18 no.1
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• pp.147-154
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• 2006

1. Objectives This study was aimed to evaluate marker substances in Gamijowi-tang by high performance liquid chromatography(HPLC) 2. Methods The seperation was performed an AquasilC18(4.6X250mm)column by gradient elution with 0.1N H3PO4 in H2O - acetonitrile(0min 100:10,20min60:40, 40min 80:20, 60min 100:0) as the mobile phase at a flow-rate of 1.0 ml/min with detection at 190-800nm 3. Results Ephedrine and schizandrin were established as marker substances in Gamijowi-tang and its qualitative analysis was carried out. Analyzed was similarity of marker substances between in standard article and in Gamijowi-tang. The result of the analysis was that ephedrine and schizadrin showed 0.9999 of similarity, which meant they were really ephedrine and schizadrin. In addition, ephedrin content was 12.16mg, pseudoephedrine conrenr was 5.09mg, and schizandrin content was 26.6mg in 76g of Gamijowi-tang. 4. Conclusions Qualitative and quantitative analyses of ephedrine and schizandrin in Gamijowi-tang were conducted, and it was identified thar they could be used as marker substances in standardizing quality of Gamijowi-rang.