본 연구는 케일(Brassica oleracea L. var. acephala)의 노지 재배 시, 생육 초기에 노출될 수 있는 건조 스트레스 조건에서 Glutamate (Glu)의 스트레스 경감 및 생육 회복 효과를 구명하기 위해 실시하였다. 건조 조건(D)에 노출된 케일에 5㎛ Glu 용액을 경엽처리하였다(D+Glu). Glu 처리 전 및 처리 후 4, 8일 차(0, 4, 8DAT)의 생육과 엽록소 함량을 측정하고 식물 체내의 ABA와 Glu, Pro의 함량을 분석하여 정상 환경 및 D, D+Glu 처리구 간의 비교를 실시하였다. 엽록소 함량의 경우, 8DAT에서 D+Glu 처리구는 일정한 수준을 유지한 반면에, D처리구는 14% 감소하였다. 엽면적으로 대표되는 생장 또한 D+Glu 처리구가 D 처리구에 비해 높게 나타났다. 또한 4, 8일차의 ABA 함량이 D 처리구에서 D+Glu 처리구에 비해 44.13, 49.18% 높게 나타났으며, 체내 아미노산 대사 및 건조저항성 지표인 Glu, Pro 함량은 D 처리구에 비해 D+Glu 처리구에서 보다 높은 수준을 유지하였다. 이러한 결과를 통해, Glu 처리에 의해 건조 스트레스가 경감되고 생육이 회복될 수 있다고 판단된다.

Coal-tar pitch, a feedstock which can be heat-treated to create graphite, is composed of very complex molecules. Coal-tar pitch is a precursor of many useful carbon materials (e.g., graphite, carbon fibers, electrodes and matrices of carbon/carbon composites). Modified coal-tar pitch (MCTP) was prepared using two different heat-treatment methods and their properties were characterized and compared. One was prepared using heat treatment in nitrogen gas; the other was prepared under a pressure of 350 mmHg in air. The MCTPs were investigated to determine several properties, including softening point, C/H ratio, coke yield, formation of anisotropic mesophase and viscosity. The MCTPs were subject to considerable changes in chemical composition due to condensation and polymerization in the used-as-received coal-tar pitch after heat-treatment under different conditions. The MCTPs showed considerable increases in softening point, C/H ratio, and coke yield, compared to those of as-received coal-tar pitch. The MCTP formed by heat-treatment in nitrogen showed isotropic phases below 350˚C for 1 h of soaking time. However, MCTP heat-treated under high pressure (350 mmHg) showed isotropic phases below 300˚C, and showed anisotropic phases above 350˚C, for 1 h of soaking time. The viscosity of the MCTPs increased with increase in their softening points.

Coal tar is the primary feedstock of premium graphitizable carbon precursor. Coal tars are residues formed as byproducts of thermal treatments of coal. Coal tar pitches were prepared through two different heat treatment schedules and their properties were characterized. One was prepared with argon and oxidation treatment with oxygen; the other was prepared with oxygen treatment at low temperature and then argon treatment at high temperature; both used coal tar to prepare coal tar pitches. To modulate the properties, different heat treatment temperatures (300~400˚C) were used for the coal tar pitches. The prepared coal tar pitches were investigated to determine several properties, such as softening point, C/H ratio, coke yield, and aromaticity index. The coal tar pitches were subject to considerable changes in chemical composition that arose due to polymerization after heat treatment. Coal tar pitch showed considerable increases in softening point, C/H ratio, coke yields, and aromaticity index compared to those characteristics for coal tar. The contents of gamma resin, which consists of low molecular weight compounds in the pitches and is insoluble in toluene, showed that the degree of polymerization in the pitches was proportional to C/H ratio. Using an oxidizing atmosphere like air to prepare the pitches from coal tar was an effective way to increase the aromaticity index at relatively low temperature.