Cu2ZnSn(S,Se)4(CZTSSe) thin film solar cells areone of the most promising candidates for photovoltaic devices due to their earth-abundant composition, high absorption coefficient and appropriate band gap. The sputtering process is the main challenge to achieving high efficiency of CZTSSe solar cells for industrialization. In this study, we fabricated CZTSSe absorbers on Mo coated soda lime glass using different pressures during the annealing process. As an environmental strategy, the annealing process is performed with S and Se powder, without any toxic H2Se and/or H2S gases. Because CZTSSe thin films have a very narrow stable phase region, it is important to control the condition of the annealing process to achieve high efficiency of the solar cell. To identify the effect of process pressure during the sulfo-selenization, we experiment with varying initial pressure from 600 Torr to 800 Torr. We fabricate a CZTSSe thin film solar cell with 8.24 % efficiency, with 435 mV for open circuit voltage(VOC) and 36.98 mA/cm2 for short circuit current density(JSC), under a highest process pressure of 800 Torr.

The high quality contact between graphene and the metal electrode is a crucial factor in achieving the high performance of graphene transistors. However, there is not sufficient research about contact resistance reduction methods to improve the junction of metal-graphene. In this paper, we propose a new method to decrease the contact resistance between graphene and metal using directly grown graphene over a metal surface. The study found that the grown graphene over copper, as an intermediate layer between the copper and the transferred graphene, reduces contact resistance, and that the adhesion strength between graphene and metal becomes stronger. The results confirmed the contact resistance of the metal-graphene of the proposed structure is nearly half that of the conventional contact structure.

본 연구는 토마토의 도장 억제를 위하여 보다 안정적인 건묘를 생산하고자 육묘 기간 중 diniconazol 처리시기 처리농도에 따른 경엽처리와 침지 시간에 따른 종자처리가 묘 도장 억제에 미치는 영향을 알아보고 적정 방법을 구명하고자 수행하였다. Diniconazol 처리시기 및 처리농도에 따른 토마토의 초장 신장을 본 결과 1단계 2단계 3단계로 초장의 신장과 절간장 억제가 잘 나타났다. 이는 이른 시기가 늦은 시기보다 식물체가 받는 약제의 양이 더 많기 때문에 약제 효과가 잘 나타났다. 1단계는 4절, 2단계, 3단계는 각각 3절, 2절로 억제된 절간수가 줄어들었다. 약제 지속성이 초장의 신장에 미치는 영향을 본 결과 1단계, 2단계 5mg·L-1은 약제 처리 후 초장의 신장억제가 나타났으나 다른 처리구에 비해 일정한 시간이 지나면 빨리 회복하는 경향이 나타났다. 3단계에서는 초장 신장 억제 기간이 짧았고 빠른 회복을 보였다. 1단계는 5주, 2단계, 3단계는 각각 4주정도 약제 지속효과가 나타났다. 육묘 종료 후 정식한 결과 생체량이 빨리 증가 되어 생육에는 무처리와 유의차가 없었다.

본 연구는 공정육묘시 triazole계 약제처리가 과채류의(토마토, 오이 및 고추) 묘 도장억제에 미치는 영향을 구명하고, 도장억제에 가장 효과적인 약제를 선발하며, 또한 선발된 약제의 과채류 적정 처리농도와 처리시기를 구명하고자 수행하였다. Triazole계 약제는 품목과 관계없이 농도가 증가할수록 줄기 신장을 억제시켰다. 약제 별 품목별로 diniconazole 처리가 높은 왜화율을 보였으며, tebuconazole과 hexaconazole도 좋은 왜화 효과를 보였다. Diniconazole 처리에 있어서 처리 농도가 증가함 따라 오이, 토마토 및 고추의 초장이 감소하였는데, 오이의 경우 5mg·L-1 에서 30% 왜화율을 보였으며 100mg·L-1 에서는 약 60% 의 왜화율이 나타났다. 또한 토마토와 고추에서는 처리시 기와 관계없이 25mg·L-1 처리구서 3096 왜화효과를 보았다. 공정육묘시 diniconazole 처리를 할 경우 오이 와 토마토는 5mg·L-1 농도를 2차 생육단계에서, 고추는 5mg·L-1 농도를 1차 생육단계에서 처리하면 건실한 묘를 얻을 수가 있었다.

본 시험은 1998년 충남 성환에 있는 천원목장의 불경운초지 및 임간초지에 선점식생을 제거하지 않고 피복종자를 겉뿌림하였을 때 목초의 정착 및 초기생육을 비교하기 위하여 수행하였다. 불경운초지에서 tall fescue 및 orchardgrass 피복종자의 정착률 및 초기생육은 처리간에 유의적인 차이가 없었다. 불경운에서 alfalfa 피복종자는 정착률과 초기생육이 각각 4.7% 및 로 부처리에 비하여 높았다 (p<0.05). 한편 임간초지에서 tall

1. 분얼수는 3차 예취기에서가장 많았으며, 이시기까지 계속 증가를 하였지만 가을 예취기에서 급격히 감소했다. 엽면적 지수는 3차 예취기에서 가장 높았으며, 보통 예취직후 서서히 증가를 하다가 15~20일부터 빠르게 증가하였다. 2. 各 예취기 건물수량은 1次와 3次 ~예취가 다른 時期에 比하여 높게 나타났으며, 예취기별 건물중 變化는 葉面積 指數의 變化와 비슷한 樣相을 보이고 있었다. 3. LER은 예취후 20-30일l, SLW는 25-30日, CGR

A field experiment was conducted in order to investigate the seasonal changes of leaf growth and related characteristics in three cultivars of orchardgrass; Potomac, Kay and Sumas. The results were summarized as follows: 1. Leaf elongation was increased i

The response of forage yield was studied with various growth indices to develop yield model and to determine optimum cutting time in three cultivars of orchardgrass. 1. Number of tiller per plant was the highest at 3rd cutting stage. But, it was decreased

This study was conducted to monitor the growth and development of Abies koreana seedlings in the Hallasan Mountain. Accordingly, the obtained results indicate that the number of A. koreana seedlings increased by 2.6 and 4.8 times in the Yeongsil and Jindallaebat areas, respectively, over the 10-year period. Most of these seedlings were found to be growing on moss-covered rocks. The average tree height over the last 10 years was obtained as 20.4 cm in the Yeongsil area and 3.6 cm in Jindallaebat with growths of 4.1 cm and 1.4 cm, respectively over the last 2 years. Of all the mature trees that were surviving in 2009, 6 died in Yeongsil in 2014 (with an additional 4 in 2018) and 13 in Jindallaebat in 2016. Over the 10-year period, the diameter at breast height of the trees in Yeongsil and Jindallaebat has increased by an average of 0.6 cm and 4.2 cm. Similarly, an average of 6.8 cones was found in the Yeongsil area in 2014 and 26.3 in Jindallaebat in 2016. However, in 2018, no additional cones were found in the former, although an average of 1.4 cones was observed in the latter. With respect to the average temperature and relative humidity, no significant difference could be observed between two monitored areas from 2016 to 2018. However, in July 2017 and February 2018, the average temperature was higher in the Jindallaebat area, while relative humidity was higher in Yeongsil, there by possibly affecting cone growth and flowering between areas. These results indicate the survival and growth of A. koreana seedlings in the Hallasan Mountain is sensitive to the environments of each area. Hence, continuous monitoring of the environment changes and in-depth studies on the flowering and fruiting of A. koreana seedlings needs to be carried out in order to analyze the relationship between their survival rates and changes in weather conditions.

Background: Ginseng produced by hydroponics can be cultivated without using agricultural chemicals; thus, it can be used as a raw materials for functional foods, medicines, and cosmetics. This study aimed to determine the optimal harvesting time to obtain the highest levels of ginsenoside and ginseng, as this was not previously unknown. Methods and Results: One-year-old organic ginseng seedlings were transplanted and cultivated using hydroponics for 150 days in a venlo-type greenhouse, using ginseng nursery bed soil and a nutrient solution (NO3 −-N; 6.165, P; 3.525, K; 5.625, Ca; 4.365, Mg; 5.085, S; 5.31 mEq/ℓ). Ginsenoside content and fresh and dry weights were higher at 120 days after transplanting than at 30, 60, 90, and 150 days. Total ginsenoside content was 11.86 times higher in the leaf and stem than in the root at 120 days after transplanting. Ginsenosides F1, F2, F3, and F5 were detected in ginseng leaves and stems. These chemical compounds are known to be effective in altering skin properties, including whitening, anti-inflammation, and anti-aging. Conclusions: Optimal harvesting time for ginseng cultivated using hydroponics was 120 days after transplanting when the biomass and ginsenoside content were highest.