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Synthesis of p-phenylenediamine (PPD) from p-Diiodobenezene using Copper(1) catalyst
이상용,김정석,서휘민,강나영,박선영,최원춘,박용기,구기갑 한국공업화학회 2015 한국공업화학회 연구논문 초록집 Vol.2015 No.0
Aramid fiber is well known to have excellent physical properties such as high thermal resistance and durability. In this work, for the production of p-Phenylenediamine(PPD), which is used as a precursor of para aramid fiber, the reaction of p-Diiodobenzene (PDIB) with a copper iodide catalyst was investigated. In general, as an amine donor for the copper-catalyzed amination of aryl halide, ammonia surrogates are used and results in additional process cost. However, in the present work, to avoid an unnecessary process and the production of undesirable compounds, ammonia was directly applied and found to work successfully. For the improvement of the reactivity, the reduction of the copper catalyst was achieved by using ascorbic acid and dihydroxyfumaric acid.
이상용,이효 한국지방재정학회 2007 한국지방재정논집 Vol.12 No.1
The ageing of population by low fertility and increase of average length of life is a common trend in almost all the industrialized countries. In Korea the total number of the elderly over age 65 exceeded 484.9million(9.5%) in 2006. Korea is faced with the increasing welfare needs by a rapid evolution of population ageing like this and it is also expected to sharply expand the expenditure of elderly welfare services such as pension, medical expense, care payment. so local governments will financially suffers a difficult conditions in the near future. The purpose of this study is to suggest policy directions and alternatives on welfare finance management in response to aged society.Policy alternatives for improving welfare finance System are pursued in terms of institutional improvements such as establishment of financial share principle among governments, enlargement of local share tax' role in social welfare service, introduction of block grant regarding welfare finance in local government.
이상용,장중순 한국경영과학회 2001 한국경영과학회 학술대회논문집 Vol.- No.1(3)
It is a characteristic of web log files that their sizes have heavy tailed distributions. This paper proposes a TTT plot method of identifying such properties, which is used in reliability analysis. Simulated comparison study of their performances is performed and log files in Korean Edunet and NASA servers are analyzed using proposed methods.
Zr-Sn-Fe-Cr 및 Zr-Nb-Sn-Fe 합금 피복관의 기계적 특성 및 Creep 거동
이상용,고산,최영철,김규태,최재하,홍순익,Lee, Sang-Yong,Ko, San,Choi, Young-Chul,Kim, Kyu-Tae,Choi, Jae-Ha,Hong, Sun-Ig 한국재료학회 2008 한국재료학회지 Vol.18 No.6
Since the 1990s, the second generation of Zirconium alloys containing main alloy compositions of Nb, Sn and Fe have been used as a replacement of Zircaloy-4 (Zr-Sn-Fe-Cr), a first-generation Zirconium alloy, to meet severe and rigorous reactor operating conditions characterized by high-burn-up, high-power and high-pH operations. In this study, the mechanical properties and creep behaviors of Zr-Sn-Fe-Cr and Zr-Nb-Sn-Fe alloys were investigated in a temperature range of $450{\sim}500^{\circ}C$ and in a stress range of $80{\sim}150\;MPa$. The mechanical testing results indicate that the yield and tensile strengths of the Zr-Nb-Sn-Fe alloy are slightly higher compared to those of Zr-Sn-Fe-Cr. This can be explained by the second phase strengthening of the $\beta$-Nb precipitates. The creep test results indicate that the stress exponent for the steady-state creep rate decreases with the increase in the applied stress. However, the stress exponent of the Zr-Sn-Fe-Cr alloy is lower than that of the Zr-Nb-Sn-Fe alloy in a relatively high stress range, whereas the creep activation energy of the former is slightly higher than that of the latter. This can be explained by the dynamic deformation aging effect caused by the interaction of dislocations with Sn substitutional atoms. A higher Sn content leads to a lower stress exponent value and higher creep activation energy.