This experiment was conducted to investigate the effects of pH on the mineral nutrient uptake and growth of the four Chinese chives species. The Chinese chives species used in the experiment were the cultivated species grown in the farm (cultivated Allium tuberosum) and three wild species of wild Allium tuberosum, A. thunbergii and A. senescens. The pH levels of soil medium were set to be 4.5, 6.5, and 7.5. Fresh weight (FW) of cultivated A. tuberosum was highest at all pH levels. The increase of soil pH increased the FW of the wild A. tuberosum and A. thunbergii, but no difference was noted for the A. tuberosum and A. senescens. Plant height was higher in the order of wild A. tuberosum, A. thunbergii, and cultivated A. tuberosum and A. thunbergii. Notably plant height of the wild A. tuberosum increased significantly by the pH increase. The Zn content of the wild A. tuberosum was shown to be significantly higher than that of the other species and increased with the increase of soil pH. This indicates that there is a close relationship between the plant height and Zn content in Chinese chives plant. Principal component analysis for characterizing closely related A. species using the factors of plant growth and amounts of nutrients uptake showed that the cultivated A. and wild A. tuberosum were in the 4th quadrant of the graph which are classified as the same species, while A. senescens and thunbergii was in 1st and 3rd quadrant indicating different species, respectively.

We have determined the disk size of Be stars by using Hα emission. We observed spectra of Be stars with telescope in SNU, equipped with SB SGS (Santa Babara Self Guided Spectrograph) and CCD ST-8. The size of disk of Be stars was estimated with the Be star model of Grundstrom & Gies (2006). This study suggests that the medium resolution spectra taken with small telescope equipped with commercial spectrograph are useful to estimate the approximate size of the Hα emitting disk around Be stars.

본 연구는 아연폐광지역의 토양에 토양개량제를 처리한 후 구절초와 층꽃나무의 생장반응을 연구함으로서 생태계 복원을 위한 기초자료를 얻고자 실시하였다. 아연폐광지의 토양은 유기물 함량ㅇ이 낮았고, 토양 중 중금속 이온은 Zn의 함량이 가장 높았고 Pb, Cu, Cd순이었다. 아연폐광지역 토양에 슬러지 처리 시 유기물 함량이 가장 높았고, 중금속 이온 함량은 토양개량제 초리구간의 차이가 적었다. 생육반응을 보면 구정초와 층꽃나무 모두 슬러지 처리구의 효과가 나타났다. 구절초와 층꽃나무의 가용성 단백질, 엽록소 함량, 엽록소 형광 반응은 슬러지 처리구에서 가장 높았고, 광함성량과 증산량도 슬러지 처리구에서 높았다. 중금속 축적량은 구절초는 슬러지 처리구에서 낮았던 반면 층꽃나무는 슬러지 처리구에서 높았다.

A large scatter of the chemical abundances among globular cluster red giants has been observed. Especially the chemical elements C, N, O, Na, Mg, and Al vary form star to star within globular clusters. Except for ω Cen and M22, most globular clusters could be considered to be monometallic of their iron peak elements within error ranges. The variations in light elements among globuar cluster giants appear much more pronounced than in field halo giants of comparable Fe-peak metallicity. It has been found that in general the nitrogen abundance is anticorrelated with both carbon and oxygen, while it is correlated with Na and AI. These intracluster abundance inhomogeneities can be interpreted either by mixing of nucleosythesized material from the deep stellar interior during the red giant branch phase of evolution or by inhomogeneities of primordially processed material, from which the stars were formed. The simple way of distingushing between two senarios is to obtain the element abundances of main-sequence stars in globular clusters, which are too faint for high resolution spectroscopic studies until now. Both 'evolutionary' and 'primodial' origins are accepted for explanations of abundance variations among red giants and CN-CH anticorrelations among main-sequence stars in globular clusters. This paper reviews chemical abundances of light elements among globular cluster giants, with brief reviews of cannonical stellar evolution of low mass stars after main-sequence and deep mixing for abundance variations of cluster giants, and a possible connection between deep mixing and second parameter.

We have improved the control and driving system of 16' reflector at Kwanak Observatory at Seoul National University, by completing encoder unit, and by developing programs for correction of errors resulting from hardware defects. The hardware defects of this telescope system are the large backlash and the nonuniform tracking and pointing. The telescope pointing accuracy for RA is improved to a few arc minutes, and that for DEC is several tens of arc minutes. The guiding error is improved to 0.7 arcsec/minute, allowing up to 3 minutes exposure for CCD imaging under typical seeing conditions at the Observatory.

In principle, both radiation and collision are capable of pumping the SiO masers. In order to check which pumping mechanism is more efficient, we calculated the rate equation for our model including the 3 vibrational slates with 7 rotational states of each vibrational slate. Through solving the radiative transfer equation with the Sovolev approximation, we estimated the line profiles from an expanding envelope for several transitions. It is found that the collision works more efficiently than the radiation for the inversion in excited vibrational stales. However in an expanding envelope model we could not get the strong line intensity as observed one because the population inversion is possible only in a small restricted region. For the enough population inversion to get type observed maser intensity. the number density of SiO and hydrogen molecules should be up to about 2×105cm−3 2×105cm−3 and 1×109cm−3 1×109cm−3 , respectively, and the inversion should be occured in the region of no Jess than 11014cm.