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        검색결과 126

        82.
        2000.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Raman spectroscopy has been used to investigate the structure of coal tar pitch heat-treated up to 3000℃ by using 514.5 run Ar ion laser line. Four critical temperature ranges were found on pyrolyzing coal tar pitch, which correspond to four distinct processes from disordered carbons to the well-ordered graphite structure. The range of heat treat temperature (HTT) below 1000℃ corresponds to gas evolution during the pyrolysis of coal tar pitch. Above the HTT are correlated to rearrangements of enlarged molecules, growth of the molecules along the direction of plane, finally stacking in the normal direction of the plane, in the respective HTT ranges of 1000-2000, above 2000 and 2500-3000℃.
        4,000원
        83.
        1999.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        We have made an extensive mapping of the 13CO 13CO J=1-0 transition line in the dark cloud L1535. We also constructed the 100μm 100μm IRAS map in the region. We found a semi-detached cloud component of 13CO 13CO in the northeast direction of the 13CO 13CO main cloud which forms a dumbbell-like structure. This additional component with an angular size of 20′×16′ 20′×16′ has not been observed before in any molecular surveys of the cloud. The IRAS map shows a similar structure with two intensity peaks whose positions coincide with those of the 13CO 13CO clouds.
        3,000원
        85.
        1999.10 구독 인증기관·개인회원 무료
        86.
        1999.06 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        Open clusters are useful tools to investigate the structure and evolution of the Galactic disk. We have started a long-term project to obtain UBVI CCD photometry of open clusters which were little studied before, using the Doyak 1.8 m telescope of Bohyunsan Optical Astronomy Observatory in Korea. The primary goals of this project are (1) to make a catalog of UBVI photometry of open clusters, (2) to make an atlas of open clusters, and (3) to survey and monitor variable stars in open clusters. Here we describe this project and report the first results based on preliminary analysis of the data on four open clusters in the survey sample: Be 14, Cr 74, Biu 9, and NGC 2355. Isochrone fitting of the color-magnitude diagrams of the clusters shows that all of them are intermediate age to old (0.3-1.6 Gyrs) open clusters with moderate metallicity.
        4,000원
        90.
        1996.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        실내에서 담배거세미나방의 영기별 약제감수성을 조사한 결과 시험된 약제 모두 유충의 영기가 높아질수록 약제감수성은 낮았다. Chlorpyrifors-methyl과 chlorpyrifos의 독성은 3령부터, etofenprox+PAP와 deltamethrin은 2령부터 현저히 떨어졌다. 포트시험결과 deltamethrin을 제외한 4약제 모두 90% 이상의 방제가를 보여 담배거세미나방의 방제에 유용하게 사용될 수 있을 것으로 생각된다. 하지만 야외에서 담배거세미나방은 전 영기가 혼재되어 있고 영기별 약제감수성이 다르기 때문에 적절한 약제선택은 물론 유충 발생초기에 약제를 살포하는 것이 중요하다.
        4,000원
        92.
        1996.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        우리나라산 주머니나방과의 1미기록종, 유리주머니나방(Acanthopsyche nigraplaga Wileman)을 보고하며 수컷 생식기 도해와 함께 외부형태를 간약하게 기술하였다. 도한 천일홍, 명석딸리 차조기, 새모래덩굴, 흰명아주 5종의 기주식물도 처음으로 확인하였다.
        3,000원
        95.
        1992.12 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        Effects of cloud rotation 011 the profiles of CO J= 1 → 0 lines arc investigated by theoretically general ing line profiles under physical conditions similar to t he ones in large globules. The synthesized profiles are presented and their characteristics are discussed. It is found that when the Doppler shift of the observed CO lines is interpreted as the rotation velocity, the optically thin 13 C O lines underestimate the rotation velocity by up to 10 percents, while the self-reversed optically thick 12 C O lines overestimate the velocity up to 20 percents. The optically thin line is shown to be of use in probing the distribution of rotation velocity in dark globules.
        4,600원
        96.
        1981.12 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        Theoretical profiles of selected rotational lines of C 2 CH, CN, TiO and MgH are computed by using the current models of sunspot unbrae and penumbrae. It is found that the lines of the diatomic carbides are enhanced in penumbrae relative to umbrae, while MgH lines are more strongly enhanced in umbrae than in penumbrae and the quiet photosphere. The results are discussed with respect to selecting lines suitable for studying the structure of sunspots.
        4,000원
        98.
        1980.12 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        Surface density distributions for globular clusters were obtained from photoelectric surface photometry (using centered aperture photometry). These surface brightness profiles were then compared with the theoretical surface density distribution of King's model. From the comparison of the theoretical and observed surface density distributions, we determine he structural parameters of the clusters (the core radius r c , the tidal cut off r t , and the concentration factor C).
        4,000원
        99.
        1980.12 구독 인증기관·개인회원 무료
        100.
        2018.05 서비스 종료(열람 제한)
        The Stockholm Convention was adopted in Sweden in 2001 to protect human health and the environment, including Persistent Organic Pollutants Rotors, such as toxic and bioaccumulative. Currently, there are 28 kinds of materials. This prohibits and limits the production, use, and manufacture of the product. Korea is a party to the Convention and it is necessary to prepare management and treatment plan to cope with POPs trends. In the text, we have discussed HCBD materials. HCBD belongs to halogenated aliphatic unsaturated hydrocarbons. It is a toxic, organic mixture of bioaccumulation. A study on the treatment of waste containing HCBD substance, We decided to treat the waste containing HCBD thermally. So six samples were selected. Waste water treatment sludge, rubber plate, insecticide, tarpaulin, tire rubber, mixed sample. The tire rubber injected HCBD as a technical sample. HCBD analysis showed that 59.345 ~ 18,238.355 ug/kg was detected. For the thermal treatment, we analyzed element. As a result of thermogravimetric analysis, the weight change due to the decomposition of the material started at 200℃. The material decomposition was completed within 800℃. The thermal treatment was performed on a Lab-scale (1kg/hr). After exhaust gas analysis result, HCBD was detected at 0.01 to 0.09 ug/kg. The decomposition rate is estimated to be 99.848 ~ 99.999%. As a result of dioxin analysis in the exhaust gas, the highest concentration was found in the tarpaulins and the emission limit was exceeded. The concentrations of Cd, Pb, Cr, Cu, Ni and Zn in the residues were very low. Considering the decomposition rate of HCBD containing wastes, incineration treatment at 2 ton/hr or more is considered to be possible. And unintentional persistent organic pollutants such as dioxins in the exhaust gas. Therefore, it is considered safe to operate the incineration temperature at more than 1100℃.
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