• 한국환경농학회지
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• 제38권1호
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• pp.47-53
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• 2019

BACKGROUND: This experiment was conducted to examine the effects of organic Se concentration and the number of foliar applications on growth characteristics and Se content in rice. METHODS AND RESULTS: A series of multiple foliar applications were performed at (1) 3 times (maximum tillering stage + booting stage + heading stage), (2) 4 times I (effective tillering stage + maximum tillering stage + booting stage + heading stage), (3) 4 times II (maximum tillering stage + booting stage + heading stage + grain filling stage) according to the development stage. Each set of the foliar application plots was treated with 0, 10, 20, 40, 60, 100 ppm of Se and with mixed pesticide ($P^*$ + Se 40 ppm) in which the treatment time was the same as that of the treatment 4 times II. The total cultivation period of rice was 184 days. Se contents in rice (brown rice, white rice) were analyzed by ICP. CONCLUSION: The number of grains per head tended to decrease with increasing concentrations of organic Se in all treatments. However, number of panicles per hill did not show statically significant differences between the 3 times and 4 times I treatments. The grain yield decreased with the 3 times and 4 times II, but there was no significant difference in 4 times I. Se content in brown rice was the highest at 100 ppm Se (5268.64) treatment and lowest at 10 ppm Se ($1269.19{\mu}g{\cdot}kg^{-1}$) treatment. Se content in the polished rice was the highest at 100 ppm Se (5047.33) treatment and lowest at 10 ppm Se ($885.05{\mu}g{\cdot}kg^{-1}$) treatment. The higher selenium was treated, the higher Se content was found in the rice (brown rice, polished rice).

• 한국작물학회지
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• 제41권4호
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• pp.434-440
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• 1996

수발아가 벼의 품질 및 정현 비율 감소에 미치는 영향, 수발아성의 품종간 차이 및 왕겨로부터 발아 억제물질을 추출하여 수발아 방제를 위한 기초자료를 얻고자 실시한 결과는 다음과 같다. 1. 현미중은 무처리에 비하여 수발아 처리일수가 길어질수록 감소되는 경향으로 6일 처리시 약 20% 감소되었다. 2. 수발아 처리일수에 따른 완전립 비율은 무처리가 99.5%인데 반해 6일 처리시 41.3%로 현저히 저하되었다. 3. 인디카품종은 대부분 난수발아성이었으나 자포니카(9.2∼79.7%) 및 통일형 품종(2.1∼63.7%)은 품종간 차이가 현저히 나타났다. 4. 난수발아성인 IR36, 신운봉벼 및 중원벼의 왕겨를 메탄올을 이용하여 추출한 물질이 발아억제에 효과가 있었다.

• 현장농수산연구지
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• 제20권1호
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• pp.175-185
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• 2018

개체군생장율(CGR)은 유수형성기와 출수기 사이에 가장 높았는데, 주남벼, 낙동벼, 소비벼 등이 높았으며, 이삭의 등숙속도는 시비량이 증가할수록 증가하였고, 출수 후 20일까지 가장 많이 증가하고, 그 이후에는 점차 감소하는 경향이었는데, 주남벼, 소비벼에서 빨랐다. 관행재배에서 수량이 높은 품종은 소비재배에서도 수량이 높았으며, 소비재배시 수량에 가장 많은 영향을 미치는 수량구성요소는 단위면적당 영화수로, 고도의 정의 상관관계를 나타냈다. 또한 백미품위는 시비량이 증가할수록 감소하였는데, 소비벼의 품위가 가장 낮았으며, 사미와 분상 질립의 증가가 원인이었다.

• 한국유기농업학회지
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• 제15권2호
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• pp.207-218
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• 2007

웰빙시대의 도래와 함께 안전농산물에 대한 국민요구가 커져가고 있으며, 이에 따라 친환경 쌀 생산체계 개발이 절실한 실정이다. 따라서 본 연구는 최근 효과가 큰 것으로 알려지고 있는 유효미생물제제인 Amo, 발효자재인 Amo-bokasi 등 몇 가지 친환경농자재를 이용하여 친환경 벼 생산체계를 수립코자 수행한 연구결과를 하면 다음과 같다. 1. 주당 분얼수는 유효미생물처리 2, 3수준이 각각 48.8, 47.3개로 많았으며, 관행구가 41.0개로 가장 적었다. 2. 수잉기의 엽면적은 유효미생물처리구의 3수준이 $3228.5cm^2$로 가장 많았으며, 관행구는 $2264.7cm^2$로 가장 엽면적이 큰 처리구 3수준에 비하여 70.2% 이었다. 3. 유효분얼수는 관행구가 63.7%로 가장 높았으며, 친환경농자재가 가장 많이 처리된 처리 3수준구가 55.4%로 가장 적었다. 4. 주당수수는 처리구의 3수준구가 20.9개로 가장 많았으며, 관행구가 19.3개로 가장 적었으며 유의한 차이를 나타내었다. 수당립수는 처리구의 2수준구가 85.2로 가장 많았으며, 관행구가 81.9개로 가장 적어 통계적으로도 유의한 차이를 나타내었으며, 처리간에도 유의한 차이가 인정되었다. 5. 등숙율은 관행구가 85.0%로 가장 높았으며, 처리의 3수준구가 81.8%로 가장 낮았으며, 처리간에는 대차 없었다. 1000립중도 마찬가지로 관행구가 21.7g으로 가장 무거웠으며, 처리구가 전반적으로 약 1g 정도 낮은 경향을 보였다. 6. 10a당 정조중은 처리구의 2수준구에서 654.3kg으로 가장 많았고, 처리구의 3수준구에서 636.1kg으로 가장 적었으며, 이들 간에는 유의적인 차이가 인정되었다.

• 한국초지조사료학회지
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• 제37권4호
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• pp.271-276
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• 2017

본 연구는 사료용 옥수수의 내습성 검정을 위한 기초자료를 얻고자 자식 6계통을 3엽기에 30일간 습해 처리 후 옥수수의 생육 특성 및 수량 변화를 구명하고자 농촌진흥청 국립식량과학원 중부작물부 시험포장(온실)에서 수행한 결과를 요약하면 다음과 같다. 1. 습해 처리 시 모든 자식 계통이 무처리에 비하여 초장, 완전전개엽수 및 엽색도(SPAD)는 모든 계통에서 유의적으로 감소하였으며 엽색도는 KS140 계통이 높았고 KS141 계통이 낮았다. 2. 지상부와 뿌리의 건물중은 습해처리 후 모든 계통이 유의적으로 감소하였으며 자식 계통들 간에는 KS140이 가장 많았고 KS163이 가장 적었다. 부정근의 건물중은 무처리와 유의적 차이는 없었으나 KS140 계통에서 높은 경향을 보였다. 3. 수확기 옥수수의 이삭길이와 두께 및 착립이삭길이, 개체당 종실수 모두 무처리에 비하여 유의적으로 감소하였다. 무처리에 비하여 이삭 길이와 두께는 KS141 계통이 착립 이삭길와 개체당 종실수에서는 KS164 계통이 가장 적게 감소하였다. 4. 옥수수 수량은 무처리에 비하여 습해 처리한 모든 계통에서 유의적으로 감소하였으나 습해 처리 계통들 간에는 KS164 계통만 유의적으로 수량이 높아 내습성인 것으로 판단하였다. 5. 옥수수 유묘기 30일간 습해처리시 초장, 엽색도(SPAD값), 완전전개엽수가 옥수수 수량과 상관이 높았다.

• 한국분말재료학회지
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• 제10권2호
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• pp.103-107
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• 2003

Aluminum-based $Al/Al_2O_3$ composites were fabricated by a powder-in sheath rolling method. A stainless steel tube with outer diameter of 12 mm and wall thickness of 1 mm was used as a sheath. A mixture of aluminum powder and $Al_2O_3$ particles of which volume content was varied from 5 to 20%, was filled in the tube by tap filling and then rolled by 75% reduction in thickness at ambient temperature. The rolled specimen was then sintered at 56$0^{\circ}C$ for 0.5 h. The mixture of Al powders and $Al_2O_3$ particles was successfully consolidated by the sheath rolling. The $Al/Al_2O_3$ composite fabricated by the sheath rolling showed a recrystallized structure, while unreinforced Al powder compact fabricated by the same procedure showed a deformed structure. The unreinforced Al powder compact was characterized by a deformation (rolling) texture of which main component is {112}<111>, while the $Al/Al_2O_3$ composite showed a mixed texture oi deformation and recrystallization. The sintering resulted in recrystallization in Al powder compact and grain growth in the composite.

• 한국분말재료학회지
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• 제21권1호
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• pp.50-54
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• 2014

A powder-in-sheath rolling method was applied to a fabrication of a carbon nano tube (CNT) reinforced aluminum composite. A STS304 tube with an outer diameter of 34 mm and a wall thickness of 2 mm was used as a sheath material. A mixture of pure aluminum powders and CNTs with the volume contents of 1, 3, 5 vol was filled in the tube by tap filling and then processed to 73.5% height reduction by a rolling mill. The relative density of the CNT/Al composite fabricated by the powder-in-sheath rolling decreased slightly with increasing of CNTs content, but exhibited high value more than 98. The grain size of the aluminum matrix was largely decreased with addition of CNTs; it decreased from $24{\mu}m$ to $0.9{\mu}m$ by the addition of only 1 volCNT. The average hardness of the composites increased by approximately 3 times with the addition of CNTs, comparing to that of unreinforced pure aluminum. It is concluded that the powder-in-sheath rolling method is an effective process for fabrication of CNT reinforced Al matrix composites.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 춘계 학술발표회
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• pp.23-29
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• 2009

A sand-cone method is commonly used to determine the density of the compacted soils. This method uses a calibration container to determine the bulk-density of the sand for use in the test. The density of the test or compacted soil is computed on the assumption that the calibration container has approximately the same size or volume and allows the sand to fall approximately the same height as a test hole in the field. However, in most cases the size or shape of test hole is not exactly the same as the calibration container. There is certain discrepancy between sand particle settlement or arrangement in the laboratory calibration and in the field testing, which may cause an erroneous determination of in-situ density. The sand filling process is simulated in the laboratory and its effect on the determination of density is investigated. Artificially-made holes with different heights and bottom shapes are prepared to simulate various shapes of the test hole in the field. The sands with different gradations are used in the testing to examine how sand grain size influences the determination of density in the field.

• Journal of Microbiology and Biotechnology
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• 제22권5호
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• pp.585-591
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• 2012

The antagonistic effect of Trichoderma harzianum on a range of seed-borne fungal pathogens of wheat (viz. Fusarium graminearum, Bipolaris sorokiniana, Aspergillus spp., and Penicillium spp.) was assessed. The potential of T. harzianum as a biocontrol agent was tested in vitro and under field conditions. Coculture of the pathogens and Trichoderma under laboratory conditions clearly showed dominance of T. harzianum. Under natural conditions, biocontrol effects were also obtained against the test fungi. One month after sowing, field emergence (plant stand) was increased by 15.93% over that obtained with the control treatment, and seedling infection was reduced significantly. Leaf blight severity was decreased from 22 to 11 at the heading stage, 35 to 31 at the flowering stage, and 86 to 74 at the grain filling stage. At harvest, the number of tillers per plant was increased by 50%, the yield was increased by 31.58%, and the 1,000-seed weight was increased by 21%.

• Macromolecular Research
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• 제17권8호
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• pp.568-574
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• 2009

We investigated the sintering and consolidation phenomena of silver nanoparticles under various thermal treatment conditions when they were patterned by a contact printing technique on polyimide substrate films. The sintering of metastable silver nanoparticles commenced at 180 $^{\circ}C$, where the point necks were formed at the contact points of the nanoparticles to reduce the overall surface area and the overall surface energy. As the temperature was increased up to 250 $^{\circ}C$, silver atoms diffused from the grain boundaries at the intersections and continued to deposit on the interior surface of the pores, thereby filling up the remaining space. When the consolidation temperature exceeded 270 $^{\circ}C$, the capillary force between the spherical silver particles and polyimide flat surface induced the permanent deformation of the polyimide films, leaving crater-shaped indentation marks. The bonding force between the patterned silver metal and polyimide substrate was greatly increased by the heat treatment temperature and the mechanical interlocking by the metal particle indentation.