As wrought stainless steel, sintered stainless steel (STS) has excellent high-temperature anti-corrosion even at high temperature of 800ºC and exhibit corrosion resistance in air. The oxidation behavior and oxidation mechanism of the sintered 316L stainless was reported at the high temperature in our previous study. In this study, the effects of additives on high-temperature corrosion resistances were investigated above 800ºC at the various oxides (SiO2, Al2O3, MgO and Y2O3) added STS respectively as an oxidation inhibitor. The morphology of the oxide layers were observed by SEM and the oxides phase and composition were confirmed by XRD and EDX. As a result, the weight of STS 316L sintered body increased sharply at 1000oC and the relative density of specimen decreased as metallic oxide addition increased. Compared with STS 316L sintered parts, weight change ratio corresponding to different oxidation time at 900oC and 1000oC, decreased gradually with the addition of metallic oxide. The best corrosion resistance properties of STS could be improved in case of using Y2O3. The oxidation rate was diminished dramatically by suppression the peeling on oxide layers at Y2O3 added sintered stainless steel.

As well-known wrought stainless steel, sintered stainless steel (STS) has excellent high-temperature anticorrosion even at high temperature of 800ºC, and exhibits good corrosion resistance in air. However, when temperature increases above 900ºC, the corrosion resistance of STS begins to deteriorate and dramatically decreases. In this study, the effects of phase and composition of STS on high-temperature corrosion resistances are investigated for STS 316L, STS 304 and STS 434L above 800ºC. The morphology of the oxide layers are observed. The oxides phase and composition are identified using X-ray diffractometer and energy dispersive spectroscopy. The results demonstrate that the best corrosion resistance of STS could be improved to that of 434L. The poor corrosion resistance of the austenitic stainless steels is due to the fact that NiFe2O4 oxides forming poor adhesion between the matrix and oxide film increase the oxidation susceptibility of the material at high temperature.

In this study, analysis on the oxidation behavior was conducted by a series of high-temperature oxidation tests at both 800oC, 900oC and 1000 in the air with sintered STS 316L. The weight gain of each oxidized specimen was measured, the oxidized surface morphologies and composition of oxidation layer were analyzed with Scanning Electron Microscope-Energy Dispersive x-ray Spectroscopy (SEM-EDS), finally, the phase change and composition of the oxidized specimen were shown by X-Ray Diffraction (XRD). As a result, the weight gain increased sharply at 1000oC when oxidation test was conducted for 210 hours. Also, a plentiful of pores were observed in the surface oxidation layers at 900oC for 210 hours. In addition, the following conclusions on oxidation behavior of sintered STS 316L can be obtained: Cr2O3 can be formed on pores by influxing oxygen through open-pores, (Fe0.6Cr0.4)2O3 can be generated on the inner oxidation layer, and Fe2O3 was on the outer oxidation layer. Also, NiFe2O4 could be precipitated if the oxidation time was kept longer.

This study was performed to obtain the emission characteristics of odor compounds generated from a livestock wastewater treatment process. The sampling of odor compounds was performed twice, on May 9th and June 14th 2006, at 4 and 5 sites in the boundary and source areas, respectively. The odor concentrations obtained from the air dilution sensory test ranged from 10 to 100 in the boundary area. Of the 5 source sites, the odor concentrations found at the pre-treatment building had the highest values, which were 14422 and 20800 for the first and second dates, respectively. To estimate the major odor compounds produced during a live wastewater process, the contributions of 12 odor compounds to the total odor were calculated from the concentration and odor threshold values of each compound. At the pre-treatment building and outlet of the activated carbon tower of the source sites, the contribution of sulfur compounds to the odor was 97%, and at the outlet of the biofilter that of NH₃ was 90%. The order of the contribution to the odor in the boundary area sites was; from highest to lowest: H₂S, C₂H₆S, i-C₅H10O, C₃H₉N, NH₃. The correlation coefficient between the theoretical odor concentration from the odor threshold of 12 odor compounds and that obtained from the air dilution sensory test was 0.73. This result indicated a limit to the correct analysis of the odor concentration obtained from the air dilution sensory test when only 12 odorous compounds at a livestock wastewater treatment process are used. The odor removal efficiency of the deodorization facilities showed that for the activation carbon tower, the odor concentration was reduced to 4% and the contributions of H₂S, C₂H₆S and NH₃, which were estimated to be the major odor compounds, were reduced to 20, 26 and 11%, respectively. With respect to the bio-filter, the removal efficiency of the odor compounds revealed an odor concentration of 0% because the major odor compounds were calculated as negative percentages.

최근 시설물의 안전 및 유지관리에 관심이 증대되고 있으나, 발주처의 저가발주로 인해 안전진단전문기관은 부실화 되고 부실 점검 및 진단으로 인한 많은 문제점들이 야기되고 있다. 따라서 본 연구에서는 실무자들의 인식조사와 사례분석을 통해 실행대가 현황을 고찰하 였으며, 그 결과 정밀안전점검은 대가기준 조정보다는 대가기준의 효율성 증대 및 강제성 강화가 필요한 것으로 판단된다. 또한 정밀안전진단은 연면적 10,000㎡미만 시설물에 대한 대가기준 설계금액을 현재 기준에서 80%로 하향조정하고, 그 이상의 시설물에 대해서는 현행 대가기준을 적용하되, 대가기준의 강제성 강화가 필요할 것으로 판단된다.

Recently, interest in the safety and maintenance of the structures is growing. However, due to the low-cost order placed by the ordering organization, the safety diagnosis specialized institution becomes insolvent and many problems have arisen due to insufficient inspection and diagnosis. Therefore, in this study, the current status of bid cost was examined through the survey of the practitioners and case analysis. As a result, Precision safety diagnosis, the criteria cost for structures with a floor area of less than 10,000 ㎡ is lowered to 80 % from the current standard. For structures larger than that, the current criteria cost are applied, but it is deemed necessary to strengthen the rigidity of the criteria cost.

Background : Angelica dahurica Bentham et Hooker, Angelica gigas Nakai, Ostericum koreanum Maximowicz and Peucedanum japonicum Thumberg　are a major medicinal plant in north Geungbuk province. Using medicinal plants are impotant it`s ingredient. Dry condition and stroage method are not standard manual. The ingredient variation of dry condition and stroage method were not researched. Methods and Results : Using plant material were cutivated on Gyongsangbukdo Bonghwa area. It were studied ingredient variation after dry and storage condition by HPLC methods. Major ingredient of Angelica gigas Nakai are decurusin, decurusinangelate. Heated air bulk dry get more decursin than natuarl dry and decurusinangelate of natural bulk dry was higher than heated air bulk dry. Major ingredient of Ostericum koreanum Maximowicz are imperatorin and isoimperatorin.. Imperatorin of Ostericum koreanum was highest peak on 50℃ heated-air dry after plastic bag sorage and isoimperatorin was highest peak on 40℃ heated-air dry after mountain cultivation. Imperatorin is a major ingredient Angelica dahurica Bentham et Hooker. Heated air bulk dry get more decursin and decursinangelate than natuarl dry and small heated-air dry. Peucedanol-7o_glucoside is a major ingredient Peucedanum japonicum Thumberg. Natural bulk dry get more peucedanol-7o_glucoside than heated-air bulk dry. Conclusion : Ingredient of Angelica dahurica Bentham et Hooker, Angelica gigas Nakai, Ostericum koreanum Maximowicz are different under various cutivation, drying method, storage. Diffent Ingedients of Angelica gigas Nakai, Ostericum koreanum Maximowicz were not accord it’s optical conditon.

Background : Schizandra chinensis Baillon have five tastes and lately it is using a beverage broadly. Schizandra chinensis is one of the top producing medicinal plant in Korea. Mungyeong of Gyongbuk province produce almost of Schizandra chinensis. Maturity of Schizandra chinensis get 3 years and proliferation of Schizandra chinensis was not a manual. It is needed that a new cultivar has a big fruit and high quality chracteristics using processed food and beverage. Methods and Results : 105 lines of Schizandra chinensis were collected on Mungyeong, Yeongwol, Jinan. It were studied it’ characteristics especially it’s fruit trait. Fruit traits of Schizandra chinensis were researched on fruit length, fruit weight, maturity, number of fruit, male and female ratio, powdery mildew. Fruit length of Schizandra chinensis is relation of fruit weight. It were founded 15 lines of long fruit length. 5 lines were studied high fruit weight and it’s weight were 32 to 41g. Number of fruit has relation with fruit weight and high fruit weight gets many fruits. it’s numer of fruits were 3 to 41. Male and female ratio were very impotant characteristic. High level of female ratio has quantity of fruit. High level of female ratio were founded 2 lines. Finally It was selected 3 good breed lines of Schizandra chinensis. Conclusion : 105 lines of Schizandra chinensis Baillons were collected on Mungyeong, Yeongwol, Jinan. It were founded 15 lines of long fruit length and 5 lines were studied high fruit weight. High level of female ratio were founded 2 lines. 3 good breed lines of Schizandra chinensis were selected.

Background : Management of air temperature are known to primarily affecting on physiological properties and yield in plant. Methods and Results : The effect of air temperature on characteristics of photosynthesis and chlorophyll fluorescence in Schisandra chinensis Baillon were investigated under controlled temperature using growth chamber. Net photosyntheis rate, transpiration was measured at 1,000 μmol m-2 s-1 of photon flux density and chlorophyll fluorescence was analyzed by OJIP method. Net photosyntheis rate and transpiration rate was higher in treatment of 25℃. As results of chlorophyll fluorescence by OJIP analysis, maximum quantum yield (Fv/Fm) of photosystem II (PSII) and PIabs was higher in treatment of 25℃ which reflects the relative reduction state of PSII. But in treatment of 35℃ the relative activities per reaction center such as ABS/RC, DIo/RC were higher than in treatment of 25℃ which implied that the relative reduction of electron transport at PSI and increasement of photo inhibition at reaction center. Conclusion : This result implies that 25℃ of air temperature may be a adequate temperature to improving the efficiency of photosynthesis through controlling a photosystem in Schisandra chinensis Baillon.