Part I에서 도출된 기초 식을 적용하여 입자 분산 강화형, 섬유 강화형 및 적층형 복합재료의 유효탄성제수 및 열팽창계수를 산정 하였다. 일방향 섬유 강화 복합재료의 경우 섬유의 유효 축비 (aspect ratio)가 고려되었으며, 유효 탄성계수는 다른 연구 결과들과 비교하였다. 입자 분산 강화형 복합재료의 유효 체적탄성률 및 전단 탄성률은 Korner의 표식 및 Hanshin과 Shtrikman의 하한치 (lower bounds)와 일치하고 있다. 일방향 섬유 강화 복합재료에서는 6개, Hanshin과 Rosen의 모델에 나타낸 4개의 독립 탄성계수와 일치하고 있다.

기존의 전자 기판에서 땜납으로 사용되고 있는 Sn-Pb계 합금을 대체하기 위한 새로운 합금을 개발하기 위하여 열역학을 이용한 상평형계산을 통해 얻은 다원계 상태도를 바탕으로 적정한 녹는점과 용융구간을 가지는 Sn-Bi-In-Zn계 솔더합금을 설계하였다. 설계된 합금을 제작하여 XRD, DSC및 EDX로 분석하여 상의 확인,조성분석 및 고상점과 액상점 등의 녹음 거동을 확인하였다. 또한 열처리에 따른 미세구조의 변화를 관찰하였고, 이러한 조직변화가 기계적 성질에 미치는 영향을 경도실험과 인장실험을 통해 연구하였다.

The structure of the scale formed on the surface of Fe - Cr - X alloys exposed to 1143K high sulfidation(Ps2 = 1.11×10-7 atm, Po2 = 3.11×10-20 atm) or sulfidation/oxidation((Ps2= 1.06×10-7 atm, (Po2 = 3.11×10-18 atm) environment has been observed and analysed using XRD, SEM/EDS. To investigate the possibility of protective film formed on the surface of the alloys, Aluminium, Nickel were selected as alloying elements. Thermodynamic phase stability diagram was used to predict the reaction path of scale formed on Fe - Cr - X alloys. Parabolic rate constant(Kp) value with 6wt% Al in Fe - 25Cr alloy decreased significantly compared with the Fe - 25Cr alloy without 6wt% Al. Since thin layer of defect free sulfide film, (Al, Cr)Sx, was formed at the alloy/scale interface. Fe - rich sulfide scale at outer layer and Cr - rich sulfide scale containing porosity at inner layer of Fe - 25Cr alloy have been observed. The reaction path for these scales could be predicted by the thermodynamic stability diagram.

Cu(hfac)2,(Cu(II) hexafluoroacetylacetonate)를 프리커서로 하는 구리 화학증착에 대해 자유에너지 최소화법으로 열역학적 평형조성 계산을 수행하였다. Cu(hfac)2-Ar계의 경우Cu(hfac)2 프리커서 자체의 열분해로부터 모든 공정조건에서 증착박막내로의 탄소 출입이 관찰되었다. Cu(hfac)2-H2,계에서는 Cu(hfac)2-Ar계보다 낮은 온도에서 구리박막이 증착되며, H2입력비 및 반응온도의 증가에 따라 응축상의 석출형태는 C(s)+CuF(s)로부터 C(s)+CuF(s)+Cu(s), C(s)+Cu(s), Cu(s), C(s)의 순으로 변화되는 것으로 나타났다.

In relation to the preparation of Langmuir-Blodgett thin film, four kinds of N-alkylpyridiniurn bromide were synthesized. The values of surface tensions of these materials, measured with a Traube stalagmometer, gave the relationship between the critical micells hydrophobic radical and between CMC and temperature. Values of thermodynamic properties(δH0m, δS0m, δG0m,) for the formatoin of micelle were also obtained. Experiments gave the following results; at the temperature range between 40 and 60℃, CMC of Hexadecyl-, Octadecyl-, Eicosyl-, and Docosyl-Pyridinium Bromide were 7.64×10-4~9.13×10-4, 3.85×10-4~4.60×10-4, 2.00×10-4~2.39×10-4, and 1.07×10-4~1.28×10-4 mol/l, respectively. Surface tension, γCMC, of those were 33.49~36.00, 34.78~37.61, 35.49~37.61 and 38.76~55.80 dyne/cm, respectively, The relationship between CMC and the mumber of carbon atoms in the hydrophobic radical, N was expressed as follows : Log(CMC)=A-BN where A and B are constants. At the temperature range between 40 and 60℃, the change of Gibbs evergy (δGm) for one methylene group (-CH2-) were -0.65RT, respectively, The minus values of enthalpy change (δHm) suggest that the formation of micelle is exothermic. Additionally, the overall increase in the entropy change (δSm) with respect to the temperature increase suggests that the formation of micelle is attained by a exothermic enthalpy directed process.

The adsorptions of 2-(dimethylalkylammonio)propanoates with straight chain alkyl group having from 12 to 16 carbon atoms on the liquid-air interface were decreased while lowering the surface tensions at critical micelle concentrations. In micellization, the standard free energy changes per methylene in alkyl group were found to make same contribution to the micelle formation of corresponding C-alkylcarboxybetaines, and the standard enthalpy and entropy changes were studied within the range of temperature from 30 to 50℃.

Since the late 20th century, the urbanization in Korea has been rapidly increasing, especially in major cities like Seoul, as a result of industrialization. One of the aspects of urbanization is coating the surfaces with impervious concrete or asphalt that water cannot penetrate. In addition, various urban, such as urban heat islands, which also have a great impact on the urban environment, occur within the cities. Therefore, the urban environment is gradually becoming hot and dry, and the need for more urban parks to compensate for these negative impacts is growing. Thus, several numerical studies have been conducted to assess these problems using coupled Numerical Weather Prediction (NWP) and Computational Fluid Dynamics (CFD). In this study, an experiment was conducted to determine the accuracy of the area of the input field using Weather Research and Forecasting (WRF) model, and applying the more accurate input field to a numerical simulation using ENVI-met, in order to investigate the effect of urban parks on the thermal comfort. The results showed that an input field with a larger area is more accurate than that with a smaller area, because the surrounding terrain and cities are considered in details in the experiment with the larger area. Subsequently, the more accurate input field was used in ENVI-met, and the results of this simulation showed that the presence of the urban park increased the thermal comfort and improved the humidity conditions.

The chemical kinetics of steam reforming of polystyrene (PS) and polypropylene (PP) pyrolysis oil were studied using a ruthenium-based catalyst. The experiments were performed in a tubular flow reactor at temperatures of 530-680°C, Weight Hourly Space Velocities (WHSVs) of 0.453-7.916 h−1, and different steam and pyrolysis oil gas-phase concentrations. The activation energy of steam reforming of polypropylene oil and polystyrene oil is 136 and 142 kJ/mol, respectively. The reaction orders of polypropylene and polystyrene oils were 0.42 and 0.37, respectively. Conversions of polypropylene and polystyrene oils were 2.0-50.3 and 1.9-45.3%, respectively. Indeed, a Langmuir-Hinshelwood (LH) mechanism requiring the dissociative adsorption of pyrolysis oil and steam at two different sites on plastics appeared to be the most plausible pathway for the steam reforming reaction.

The purpose of this study is to uncover the characteristics of spatio-temporal patterns and synoptic climatic patterns of thermodynamic föhn phenomenon accompanying orographic precipitation across Mt. Halla for the recent several decades. Analyses of surface observational data reveal that thermodynamic föhn days occur mainly between mid-spring and early summer (April-June) particularly in the form of North warm-South wet type across Mt. Halla due to the accelerated moisture advection around a migratory low pressure. In extreme cases of thermodynamic föhn across Mt. Halla, more than 6.0°C of daily mean temperature difference between windward and leeward sides is observed though its spatial patterns vary seasonally. Composite maps of upper synoptic climatic variables for multiple strong föhn days show that the relative position and intensity of a migratory low or high pressure anomaly cores as well as of semi-stationary fronts and air masses affect the seasonal spatial patterns and severity magnitudes of thermodynamic föhn around Mt. Halla. These results provide a scientific basis for developing a proactive föhn prediction system to reduce potential damages of föhn phenomenon to local economic activities in Jeju Island.

The chemical kinetics of the steam reforming of the pyrolysis oil of polypropylene (PP) over a ruthenium-based catalyst has been examined as a function of pyrolysis oil and steam partial pressures at various temperatures. The activation energy of steam reforming over Ru/Al2O3 catalyst is 136 kJ/mol, and the reaction orders of pyrolysis oil and steam are 0.42 and 0.24, respectively. Fitting the experimental data to the Langmuir?Hinshelwood expression shows that the steamreforming reaction probably proceeds via the dissociative adsorption of pyrolysis oil and steam on two different sites.

This paper estimated the Arrhenius parameters as well as the pyrolysis reaction model for epoxy printed circuit boards (e-PCB) by analyzing isothermal kinetic data. This paper introduces the use of thermobalance that is capable of monitoring a weight decrease with time under pure static condition. Three isothermal kinetic experiments were performed at 270, 275 and 280oC, that were chosen within a temperature range where main decompositions were observed from nonisothermal kinetic results. Comparing experimental reduced-time-plot (RTP) with theoretical ones, the pyrolysis reaction model of e-PCB fitted best to the Avrami-Erofeev (A2) Model. Consequently, the activation energy and pre-exponential factor were then estimated to be 141 kJ⋅mol−1and 29.9 (lnA, A : min−1), respectively.

In this study, activation energy of lignite, RPF and a sample mixed both of them was obtained through kinetics characteristics analysis in pyrolysis in order to identify the applicability of RPF as an assistant fuel. TGA (Thermogravimetric analysis) was conducted with follow experimental conditions; in a nitrogen atmosphere, gas flow rate of 20 ml/min, heating rate of 5 ~ 50oC/min, and maximum hottest temperature of 800oC. As a result of TGA, it showed that pyrolysis of samples mixed with 20% and 10% of RPF were more stable than other mixed ratio, and 20% of RPF was the most similar with lignite in activation energy.

Chloride binding capacity in cementitious materials is a crucial factor for service life prediction of marine concrete. C-S-H phase have significant physical binding capacity for chloride ions. In this study, specific surface area of C-S-H with various Ca/Si ratio was measured. This study suggested effective way to compute maximum adsorption of bound chloride by C-S-H based on theory single molecular layer. In addition, surface potential is very important as a main mechanism for chloride binding adsorption. Thus, intrinsic equilibrium constant was obtained and surface potential of C-S-H was calculated in chemical equilibrium solution by means of PHREEQC. Based on the experiment results, to develop integrated system for prediction of chloride binding behaviors is final goals.