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Direct Methanol Synthesis From Methane 신기석•김상범•곽윤철•박은석•천한진•함현식 명지대학교 화학공학과 메탄올은 여러 화학분야에서 그 수요가 계속 증가하고 있는 화학연료중의 하나이다. 그러나 기존의 합성가스에서 제조되는 메탄올은 그 단가가 높고 제조 공정이 복잡하다는 단점을 가지고 있다. 본 연구는 풍부하고 저렴한 천연가스로부터 합성가스를 거치지 않고 바로 메탄올을 합성하기 위한 시도로 추진 되었다. 즉, 메탄의 부분산화반응에 의해서 메탄올을 합성하였다. 이용한 촉매로는, 이 반응에서 반응중간체의 생성을 위한 활성화에너지를 낮추는 것으로 알려진 late transition metals의 혼합산화물을 이용하였다. 각 성분의 몰 비를 변화시키면서 다양한 조합의 촉매를 공침법으로 제조하였으며, 이 촉매들을 이용하여 600 °C, 50bar의 조건에서 촉매의 활성을 조사하여 보았다. 또한 XRD, BET, TPD등의 기기분석을 통한 촉매의 특성을 파악하였다.
Welfare state is widely used, there is no common agreement as to its reference, by some it is reduced to a level of spending, by others it is elevated to a moral principle. On the left it ofter refers to a functional response of late cepitalism designed to promote false cons-ciousness : on the right the welfare state often epitomizes the collectivist threat to individualism. Welfare state attempt to construct a farmwork for aggregating social welfare provision in terms of analytically distinct policy patterns. In this paper, we associate with four state types : the positive state, the social security state, the social welfare state, the democratic corporatist state. (1) the positive state is conceived as a business government partnership whose arm is to secure, with the least possible public intervention, property holders and the operation of a market economy from social and political conflict. (2) The social security state is to guarantee for all citizens a national minimum standard of living above which they are encouraged to rise. (3) The welfare state is an adaptation to the economic and social process and change of an advanced industrial society. It is compensation for the vulerables who pay the prices of progress. (4) The democratic corporatist state is a pragmatic approach to the integratine problems of the political economy of advanced capitalism. Corporatism has been used in a variety of ways to designate the linkages between organized econo-mic interests and the structures and processes of decisionmaking in the modern state. After analysis of each welfare state types, we dealt with the Korean welfare state's policy.
The integrity of the SG(Steam Generator) tubes has been challenged by numerous factors such as flaws, operation, atmosphere, inherently degraded materials, loose parts and even human errors. Of the factors, loose parts(or foreign materials) on the secondary side of the tubes can bring about volumetric defects and even leakage from the primary to the secondary side in a short period of time. More serious concerns about the loose parts are their unknown influx path and rapid growth rate of the defects affected by the loose parts. Therefore it is imperative to detect and characterize the foreign materials and the defects. As a part of the measures for loose part detection, TTS(Top of Tubesheet) MRPC(Motorized Rotating Pancake Coils) ECT has been carried out especially to the restricted high probability area of the loose part. However, in the presence of loose parts in the other areas, wide range loose part detection techniques are required. In this study, loose part standard tube was presented as a way to accurately detect and characterize loose part signals. And the SG tube ECT bobbin coil and MRPC ISI(In-service Inspection) data of domestic OPR-1000 and Westinghouse Model F(W_F) were reviewed and consequently, comprehensive loose part detection technique is derived especially by applying bobbin coil signals
Steam Generator(SG) tube, as a barrier isolating the primary coolant system from the secondary side of nuclear power plants(NPP), must maintain the structural integrity for the public safety and their efficient power generation. So, SG tubes are subject to the periodic examination and the repairs if needed so that any defective tubes are not in service. Recently, corrosion related degradations were detected in the tubes of the domestic OPR-1000 NPP, as a form of axially oriented outer diameter stress corrosion cracking(ODSCC). According to the studies on the factors causing the heat fouling as well as developing corrosion cracking, densely scaled deposits on the secondary side of the SG tubes are mainly known to be problematic causing the adverse impacts against the soundness of the SG tubes. Therefore, the processes of various cleaning methods efficiently to dissolve and remove the deposits have been applied as well as it is imperative to maintain the structural integrity of the tubes after exposing to the cleaning agent. So qualification test(QT) should be carried out to assess the perfection of the chemical cleaning and QT is to apply the processes and to do ECT. In this paper, the chemical cleaning processes to dissolve and remove the scaled deposits are introduced and results of ECT on the artificial crack specimens to determine the effectiveness of those processes are represented.