In this study, the high-temperature oxidation properties of austenitic 316L stainless steel manufactured by laser powder bed fusion (LPBF) is investigated and compared with conventional 316L manufactured by hot rolling (HR). The initial microstructure of LPBF-SS316L exhibits a molten pool ~100 μm in size and grains grown along the building direction. Isotropic grains (~35 μm) are detected in the HR-SS316L. In high-temperature oxidation tests performed at 700oC and 900oC, LPBF-SS316L demonstrates slightly superior high-temperature oxidation resistance compared to HR-SS316L. After the initial oxidation at 700oC, shown as an increase in weight, almost no further oxidation is observed for both materials. At 900oC, the oxidation weight displays a parabolic trend and both materials exhibit similar behavior. However, at 1100oC, LPBF-SS316L oxidizes in a parabolic manner, but HR-SS316L shows a breakaway oxidation behavior. The oxide layers of LPBF-SS316L and HR-SS316L are mainly composed of Cr2O3, Febased oxides, and spinel phases. In LPBF-SS316L, a uniform Cr depletion region is observed, whereas a Cr depletion region appears at the grain boundary in HR-SS316L. It is evident from the results that the microstructure and the hightemperature oxidation characteristics and behavior are related.

Five empirical farmhouses were selected to reduce the high temperature damage in oak mushroom cultivation using bed-logs. The cultivation facilities were categorized as follows: those having two blackout curtains or one blackout curtain and outdoor oak mushroom cultivation. The inequality of the indoor condition, oak mushroom hyphae rampant ratio, and fruit body production in each test condition was evaluated. 3oC was lower in indoor temperature of cultivation facility having two blackout curtains than one blackout curtain. Specifically, the indoor air humidity average of cultivation facilities having one or two blackout curtains was 10% lower than that of outdoor oak mushroom cultivation. This condition is not ideal for oak mushroom cultivation as continuous indoor humidity control is essential for producing good fruit bodies. The Inoculated bed-log surface and oak mushroom hyphae rampant ratio of bed-logs cultivated with two blackout curtains was superior to other tested conditions. The mushroom production ratio observed in facilities with two blackout curtains was 117-204% higher than those cultivated in facilities with only one blackout curtain. Furthermore, the mushroom production ratio increased in based on these findings, we recommended five cultivation facility models to reduce high temperature damage in oak mushroom cultivation using bed-logs.

Synthesis gas is a high valued compound as a basic chemicals at various chemical processes. Synthesis gas is mainly produced commercially by a steam reforming process. However, the process is highly endothermic so that the process is very energy-consuming process. Thus, this study was carried out to produce synthesis gas by the partial oxidation of methane to decrease the energy cost. The effects of reaction temperature and flow rate of reactants on the methane conversion, product selectivity, product ratio, and carbon deposition were investigated with 13wt% Ni/MgO catalyst in a fluidized bed reactor. With the fluidized bed reactor, CH4 conversion was 91%, and Hz and CO selectivities were both 98% at 850℃ and total flow rate of 100 mL/min. These values were higher than those of fixed bed reactor. From this result, we found that with the use of the fluidized bed reactor it was possible to avoid the disadvantage of fixed bed reactor (explosion) and increase the productivity of synthesis gas.

The effects of reaction temperature and flow rate of reactants on the methane conversion, product selectivity, product ratio, and carbon deposition were investigated with 13wt% Ni/MgO catalyst. Reaction temperatures were changed from 600 to 850℃, and reactants flow rates were changed from 100 to 200 mL/mim. There were no significant changes in the methane conversion observed in the range of temperatures used. It is possibly stemmed from the nearly total exhaustion of oxygen introduced. The selectiveties of hydrogen and carbon monoxide did not largely depend on the reaction temperature. The selectivities of hydrogen and carbon monoxide were 96 and 90%, respectively. Carbon deposition observed was the smallest at 750℃ and the largest at 850℃. It is found that the proper reaction temperature is 750℃. The best reactant flow rate was 150 ml/min.

조생통일을 공시하여 파종후 3~4시간 태양열을 조사시켜 간역출아시키는 방법에 관한 시험 및 육묘상내의 온도를 달리하여 묘소질에 미치는 영향을 1977년 작물시험장 인공기상실 및 답작포장에서 검토한 결과 1. 간역출아방법은 간역출아기간중의 상토온도가 30℃부터 20℃까지의 범위로 유지된 창고 및 옥외 비닐+거적피복한 처리에서 출아가 균일하였다. 2. 간역출아기간중에 주간 47℃, 야간 12℃로 온도교차가 큰 옥외 비닐만 피복처리한 구에서는 출아상태가 불량하였다. 3. 인공기상실내에시 실시한 육묘상내온도는 육묘기에서 32℃로 출아시킨후 연화기에 주간 25℃, 야간 20℃, 경화기는 주간 20℃, 야간 15℃ 온도처리에서 묘가 강건하였고 묘소질이 양호하였다. 4. 연화기부터 경화기까지 주간 30℃, 야간 15℃의 고온처리구에서는 묘령은 현저히 증가하였으나 과번무상태가 되여 묘소질이 불량하였다. 5. 포장시험에서 실시한 육묘상보온방식에 따른 상내온도는 이중비닐턴넬시와 이중비닐턴넬후 야간거적피복처리구가 관행 비닐턴넬시에 비하여 최저온도가 3~5℃높았으며 묘소질도 양호하였다.