Concentrations of fine particulate matter (PM2.5) and several of its particle constituents measured outside homes in Houston, Texas, and Los Angeles, California, were characterized using multiple regression analysis with proximity to point and mobile sources and meteorological factors as the independent variables. PM2.5 mass and the concentrations of organic carbon (OC), elemental carbon (EC), benzo-[a]-pyrene (BaP), perylene (Per), benzo-[g,h,i]-perylene (BghiP), and coronene (Cor) were examined. Negative associations of wind speed with concentrations demonstrated the effect of dilution by high wind speed. Atmospheric stability increase was associated with concentration increase. Petrochemical source proximity was included in the EC model in Houston. Area source proximity was not selected for any of the PM2.5 constituents' regression models. When the median values of the meteorological factors were used and the proximity to sources varied, the air concentrations calculated using the models for the eleven PM2.5 constituents outside the homes closest to influential highways were 1.5-15.8 fold higher than those outside homes furthest from the highway emission sources. When the median distance to the sources was used in the models, the concentrations of the PM2.5 constituents varied 2 to 82 fold, as the meteorological conditions varied over the observed range. We found different relationships between the two urban areas, illustrating the unique nature of urban sources and suggesting that localized sources need to be evaluated carefully to understand their potential contributions to PM2.5 mass and its particle constituents concentrations near residences, which influence baseline indoor air concentrations and personal exposures. The results of this study could assist in the appropriate design of monitoring networks for community-level sampling and help improve the accuracy of exposure models linking emission sources with estimated pollutant concentrations at the residential level.

This study was carried out to investigate the best explant source and combination of media and growth regulators for the regeneration of multiple shoots in soybean (Glycine max. L. Merr.) cv. ‘Iksannamulkong’. Multiple shoots could well be directly induce

Two rice cultivars (Oryza sativa L.), Hwa-seongbyeo of Japonica type and Taebackbyeo of Indica/Japonica type, were cultivated with hydroponic culture to examine nitrogen effects on the growth responses, contents and utilizations of carbohydrates, and the ripening velocity of grains with three different N levels. Plant height and tiller number were clearly increased to 80 ppm N level compared to 40 ppm N level and then they were slightly decreased in N level of 120 ppm. Higher dry weights were appeared with 80 ppm N level than did with other N levels, showing statistically differences in both cultivars and N levels, while dry weight of roots was heavier with decreasing the N levels. Therefore, T/R ratios were not significantly different among N levels, although there was statistically differences between rice cultivars. After the flowering stage, higher water-soluble carbohydrate (WSC) and water-insoluble carbohydrate (WISC) were contained in stem compared with other parts, showing that WISC of sheath and stem, unlike WSC, was significantly different among N levels. Starch of grain, WISC, was remarkedly increased from 3.0% at just after the flowering to 52.0% and 75.0% at 15 and 30 day after the flowering, respectively, showing that lower N application had faster accumulation of starch in rice grains. N would affect the contents of carbohydrates of each tissue, and starch accumulation in rice grains.

콩의 건물축적과 단백질전류에 대한 Source-Sink변경의 효과를 구명하기 위하여 1992년에 고려대학교 자연자원대학 실험농장에서 황금콩을 공시품종으로 착협시기(R3)에 상위 40%, 하위 60%의 엽과 협을 제거하여 건물중 및 단백질함량의 변화를 조사한 결과는 다음과 같다. 1. 상엽-하협제거처리에서 하위 엽과 경 건물중이 증가하였고, 상위 종실과 협 건물중은 감소하였다. 2. 엽의 단백질함량은 상위 엽보다 하위 엽에서 높았다. 3. 종실의 단백질함량은 상엽-하협제거와 하엽-상협제거처리에서 낮았다. 4. 상엽-하협제거처리에서 엽의 단백질함량은 가장 높았고 종실 단백질함량은 가장 낮았다. 5. 본 실험의 결과에서 콩의 단백질원은 하부에서 상부로 이동하나 생식생장기간중의 장거리 전류를 위한 엽 단백질의 재이동은 약한 것으로 나타났다.

옥수수의 분얼 및 생육에 미치는 시비량의 효과를 알기 위하여 상이한 두개의 교잡종 옥수수를 상이한 4가지 시비수준에서 재배한 결과 분얼하는 IK1 /IRI가 시비수준에 큰 관계없이 분얼을 하지 않는 장야일호보다 개체당 경수가 많았고, 개체당 지상부 무게, 경엽중, 이삭무게 등도 무거웠다. IK1 /IRI의 개체당 분얼수도 시비수준에 따라 크게 영향을 받아 퇴비의 시용이 개체당 분얼수를 증가시키는데 효과적이었다.

종실·엽 겸용 신품종인 엽실 들깨를 공시하여 정식기별 채엽방법이 몇가지 엽특성과 종실수량에 미치는 영향을 알아보기 위해서 몇가지 시험을 실시한 바 그 결과를 요약하면 다음과 같다. 1. 상품가치가 있다고 보여지는 완전 전개된 주당 총채엽수는 채엽회수가 많을수록, 그리고 채엽개시시기가 늦을수록 많았으며 정식기로는 6월 20일 > 7월 20일 > 8월 20일 순이었다. 2. 채엽에 의하여 들깨의 엽장, 엽폭이 적어지고 생엽중도 감소되었으며 채엽회수가 많을수록, 정식기가 늦어질수록 더욱 심한 경향이었다. 3. 엽면적도 채엽회수가 많고, 정식기가 늦어질수록 적어져 동화량이 크게 줄어 종실수량을 감소시키는 주원인이 되었다. 4. 조기채엽과 1∼2회 채엽은 종실수량 감소가 크지 않으므로 종실·엽 겸용 들깨 재배시에는 초기채엽이나 1∼2회 채엽이 바람직하였다. 5. 종실·엽 겸용 재배를 목적으로 할 경우 5월 10일 파종, 6월 20일 정식이 가장 적합하며, 6월 10일 파종, 7월 20일 정식까지는 재배가 가능하였다. 6. 실소득면에서는 종실보다 채소엽의 가치가 높아 무채엽보다 모든 채엽처리에서 수익성이 높았다.