최근 납의 대체물질로서 연구되고 있는 바륨(Ba)과 요오도(I) 등은 차폐능은 우수하지만, 30 keV 근처의 에너지 영역에서 특성 X선이 방출되는 문제점이 있다. 본 연구에서는 황산바륨(BaSO4)과 산화비스무스(BiO)로 구성된 친환경 이중차폐체의 적용가능성을 검증하기 위한 선행연구로 몬테카를로 시뮬레이션을 통해 투과스펙트럼, 차폐율 등을 평가하였다. 평가결과, 0.6mm 두께의 Pb 단일층과 비교하여 0.1 mm 두께의 BaSO4 하부층에 BiO 층의 두께가 0.4 mm 와 0.5 mm에서는 각각 차폐율이 1.9 %, 3.9 % 높은 성능을 보였다. 뿐만 아니라, 상대적인 중량 또한 각각 34.5 %, 28 % 경량화가 가능하다는 것을 알 수 있었다.
Purpose: Team cohesion and team work are the usual components for explanation of team performance in Korean sport psychological field which is somewhat limited. So for the purpose of systematic and effective explanation of performance, this study was aimed to investigate concept of integral interaction among team members. Methods: Subjects of study were 255 middle and high schools elite players(soccer, basketball and volleyball). Results were extracted from often-ended questionnaires. Data were inductively analyzed through a meeting of experts. Results: With regard to coach interaction, players of team sports represented assimilation, communication and role, and represented assimilation, communication and dependence in regard to colleague player interaction. Conclusion: The present study has contributed to existing literature by providing basic resources to further develop the questionnaires in relation to team sports interaction. Furthermore, the findings from this research may shed light on the scientific and objective knowledge in performance improvement of team sports.
Anaerobic digestion is one of the most economical ways to treat organic wastes; the production of excessive sludge is limited; aeration is not required; operation cost is low; valuable energy resource (methane) is produced. However, propionate, an intermediate substance during the process, is known to inhibit biochemical process at high concentration; but it is difficult to be degraded biologically as its oxidation is thermodynamically unfavorable (△G>0). However, there are several microorganisms which could oxidize propionate fully by their syntrophic association. Therefore, in this research, the propionate enrichment culture was produced in large amount (~1L), and the main players which are responsible for utilizing propionate are identified. Furthermore, the kinetic parameter was obtained from this research. Seed came from two different full-scale anaerobic digesters which is located in Joongrang (JR) and Sincheon (SC). 16s rRNA gnee based metagenomics results indicated that Smithella propionica and Methanobacterium beijingense were the most dominant species in all seeds. The fact that bacterial family Syntrophomonadaceae and archaeal genus Methanosaeta were also found significantly in all seeds means that there might be symbiotic relationship among propionate oxidizing bacteria, butyrate oxidizing bacteria, hydrogenotrophic methanogens and acetotrophic methanogens in complete oxidation of propionate. Based on the first order kinetic which indicated propionate degrading rate, k (1/day) on JR and SC was represented 0.0243 and 0.0223, respectively. Also, based on Modified-Gompertz model, umax on JR and SC was represented as 0.024 and 0.016, respectively.
Adsorption using highly porous and highly functionalized sorbents is a straightforward removal technology currently being employed, however the range of contaminants is limited. A novel sorbent was synthesized from activated carbon and Zr-based UiO66 metal organic framework to remove both cationic and oxyanionic metals from aqueous solutions. The composite was characterized using FSEM-EDS, FT-IR, XRD, and TGA, and showed successful integration of UiO66 on the surface of activated carbon. Batch adsorption tests with ICP-OES reveal that the composite has removal efficiency >95% for Pb (II), Cu (II), Se (IV), and As (V). The hybrid material is a promising sorbent for the removal of both cationic and oxyanionic metals for wastewater purification.
In order to cope with some drawbacks of conventional CCS (Carbon Capture and Storage) technologies, the new way to deal carbon dioxide have been studied a lot. One way to deal emitted carbon dioxide is to convert carbon dioxide into metal carbonate salt which can be used for various purposes such as raw materials for construction, additives for paper-making industries and so on. In this method, securing the source for metal cation is important and in this research, concentrated industrial wastewater was used to supply metal cation. In the wastewater, calcium and magnesium ions were dissolved and this could make cpatured carbon dioxide to be converted to metal carbonate salts. As a result of the chemical conversion, the amount of carbon dioxide converted to the precipitated salts and the crystal structures of them were suggested. To verify the crystal structures and the composition of salt mixtures, Scanning Electron Microscope and X-Ray Diffraction analysis were utilized.
최근 국가 온실가스 저감 목표인 BAU 대비 37%의 이행과 및 에너지원 다양화 측면에서 신재생에너지 보급활성화를 위한 다양한 정책이 발표되고 있으며, 이중 수송부문 신재생에너지연료의 보급 활성화를 위한 혼합의 무화제도(RFS)가 2015년 7월 31일부터 시행되었다. 본 제도의 유일한 이행 수단으로서 바이오디젤이 경유에 혼합의무화 되어 확대보급 될 전망이다. 하지만 대부분의 바이오디젤의 원료가 수입 팜유에 의존하고 있고, 유일한 국산원료인 폐식용유는 수거한계에 달한 상황이며, 바이오디젤 가격 또한 경유 가격에 비해 고가로 가격 경쟁력이 열악한 상황이다. 따라서 본 연구에서는 저가의 안정적 원료수급이 가능한 국내외 잠재원료에 대해 조사・선별하고 확보 가능량에 대해서 추정해 보았다. 또한 각 원료물질에 대한 유통구조 및 활용기술에 대해서도 조사하였다. 그 결과 국산 원료로서는 기존 폐식용유와 동물성유지 외에 식당폐유, 음식물 처리과정에서 추출된 유분 등이 추가로 조사 되었으며, 국외 원료로서는 팜유 추출 폐유인 팜 슬러지오일 등이 잠재 바이오디젤 원료로 선별 되었다. 또한 국내 유채유 및 미세조류 등도 중장기 원료로서 조사 하였다. 각 원료의 유통경로는 대부분 국산의 경유 기존 폐식용유와 동물성유지의 유통경로에 의존하고 있었고, 저급의 원료이다 보니 전처리 및 바이오디젤 전환기술개발이 필요한 실정이었다.
Background : Both Panax ginseng Meyer and Panax quinquefolius are obligate shade-loving plants whose natural habitats are broadleaved forests of Eastern Asia and North America. Panax species are easily damaged by photoinhibition when they are exposed to high temperatures or insufficient shade. In this study, a cytohistological study of the leaf structures of two of the most well-known Panax species was performed to better understand the physiological processes that limit photosynthesis. Leaves of ginseng plants grown in soil and hydroponic culture were sectioned for analysis. Methods and Results : Leaf structures of both Panax species were observed using a light microscope, scanning electron microscope, and transmission electron microscope. The mesostructure of both P. ginseng and P. quinquefolius frequently had one layer of noncylindrical palisade cells and three or four layers of spongy parenchymal cells. P. quinquefolius contained a similar number of stomata in the abaxial leaf surface but more tightly appressed enlarged grana stacks than P. ginseng. The adaxial surface of the epidermis in P. quinquefolius showed cuticle ridges with a pattern similar to that of P. ginseng. Conclusion : The anatomical leaf structure of both P. ginseng and P. quinquefolius shows that they are typical shade-loving sciophytes. Slight differences in chloroplast structure suggests that the two different species can be authenticated using transmission electron microscopy images, and light-resistant cultivar breeding can be performed via controlling photosynthesis efficiency.
Background : This experiment was carried out to improve the labor-intensive task to construct of the traditional ginseng shading system in Korea. In this experiment the selected shading materials was new 6 kinds that HDPE - knitted- monofilament and taped PE Net, with taking into account of the amount of light and the amount of leakage to screen the UV stabilized 0.3% - 0.6%. Compared with the traditional shading material, the black-shading material (wt. 200g/㎡) and the yellow shading material (wt. 300g/㎡) was suitable for the ginseng growing environments in Korea. Methods and Results : The installation of shading system was the 45 degree slope -2 meter height from the ground with the selected shading materials for the wide structure ginseng cultivation. Temperature and light intensity was measured with a week interval from the surface to a height of 30cm. The two kinds of the 1st selected materials and the traditional black + blue two layer shading materials, aluminum screen, Canada Gintec shading material, total 5 kinds of materials were installed in wide structure. The growing environmental analysis was measured using data logs (watchdog 1600series). Conclusion : In the first selection of shading materials for Ginseng wide structure, the levels of light intensity were higher in order of blue-shading> Aluminum- shading> black-shading order. The temperatures of the under wide structures were lower in order of the black-shading< aluminum-shading screen< blue-shading order, especially the temperature of the black shading material was lower than the outside temperature. For the second selection of shading material of the ginseng wide structure, the black and yellow shading material were superior to the other materials, in the amount of light shading material and growing conditions and the degree of leakage etc. The temperatures of mid-May in wide structures of ginseng cultivation were higher in order of aluminum-screen> Canada shading materials (Gintec Co.) 2 layer material> Yellow shading> black shading order, and also the amounts of light intensity also was shown to be with the same manner
Recently, the concern on the deterioration of concrete due to de-icing salts and its counter measurements has been increased. This paper discusses the durability Assessment procedure of RC Structures against chloride attack under depicing salt environments.
This study was conducted to develop a bended steel-hybrid GFRP (Glass Fiber Reinforced Polymer) bar. The steel-hybrid GFRP bar was to develop for replacing steel rebar for RC structures which were built in the corrosive environment. To be used for RC structures, a bended type of steel-hybrid GFRP bar is required. This study explains the results of current status of the project.
This study was examined the variation of unit water content and fine aggregate ratio in concrete for nuclear power structure using a large amoung of crushed sand.
Recycled aggregate is not used the structures due to the negative perception of the quality. Using only recycled aggregate concrete structures to improve these recognition were constructed to evaluate the mechanical properties and durability. The result is determined to be applicable to 100% recycled aggregate concrete in the structure.
In order to study carbonation progress after surface repair of carbonated concrete, each carbonation penetration velocity from different repair materials of concrete structure is compared through the experiment of carbonation accelerating CO2 concentration to 100%