• 한국초지조사료학회지
• /
• 제41권3호
• /
• pp.210-216
• /
• 2021

Pollution of agricultural soil by alkaline salts, such as Na₂CO₃, is a critical and long-lasting problem in cultivable land. The aim of the study was to examine the putative role of citric acid (CA) in alleviating Na₂CO₃-stress in alfalfa. In this study, Na₂CO₃ significantly induced leaf chlorosis, inhibited plant growth and photosynthesis related parameters, increased hydrogen peroxide (H₂O₂) and reduced major antioxidant enzymes (SOD, CAD, APX) in alfalfa. However, the presence of CA these negative effects of Na₂CO₃-stress largely recovered. Interestingly, expression of antioxidant and ion transporter genes (Fe-SOD, CAT, APX, DHAR and NHX1) involved in Reactive oxygen species (ROS) homeostasis and oxidative stress tolerance in alfalfa. These findings suggest that CA-mediated Na₂CO₃ stress alleviation is an ecofriendly approach that would be useful to local farmer for alfalfa and other forage crop cultivation in alkaline soils.

• 휴양 및 경관연구
• /
• 제12권4호
• /
• pp.67-78
• /
• 2018

Hangang Artpark construction is an enterprise founded in 2018 that involved installing public artworks created by 37 different people (teams) in Hangang Park located in Yeouido and Ichon Park. An iconic public space in Seoul, Hangang Park is turning into an even better public space due to the efforts to change the park into an eco-friendly, cultural-artistic space in tandem with the change in times. The objective of the Hangang Artpark construction business is to augment the environmental and scenic value of Hangang not only to provide a space for leisurely activities but also to revive it as a cultural-artistic area. This is a study of the concept and the design and installation processes of "Thinking of each other", a project by the Hangang Artpark construction business. This art piece has been installed in the wetlands and it trails along Ichon Hangang Park, which was created during the environmental recovery project. The piece consists of sculptures molded into animal shapes that are unique to the location and ecology of the area, displayed in harmony with the park's street furniture. By showing the coexistence of animals that existed in Hangang in the past along with the current inhabitants and the natural enemies of these inhabitants, the piece displays an ecofriendly scene. Moreover, by incorporating this piece into the street facilities of the park, such as gazebos, streetlights, surveillance cameras, and perches, the piece exhibits a different kind of street view compared to the installation style of other conventional environmental artworks. The various sculptures are installed along with the street facilities throughout the trail, rather than in a specific location intended for artworks, thereby achieving harmony with the park scene. In so doing, the piece elicits in the beholder an environment-friendly way of thinking, and at the same time, gives them a sense of calm and pleasure. Further, the paper researches the methods of safely installing art pieces in public spaces and of maintaining these installations.

• 마이크로전자및패키징학회지
• /
• 제28권2호
• /
• pp.13-28
• /
• 2021

트랜지언트 전자소자는 전해질 수용액이나 체내와 같은 거친 환경에서도 작동이 가능하며 동작 이후 가수분해되어 스스로 제거되기 때문에 기존의 전자소자를 대체하여 의료 목적의 체내 삽입 소자 등 다양한 연구 영역에서 활용되고 있다. 또한 물과 효소만으로 제거가 가능한 트랜지언트 전자소자는 최근 대두되고 있는 전자 쓰레기와 환경 오염 문제를 해결할 수 있는 신개념 그린 테크놀로지로 많은 주목을 받고 있다. 하지만, 트랜지언트 전자소자의 작동 환경인 수용액과 체내는 지속적은 물 침투를 통해 소자 내 핵심 부품을 열화시킨다. 이러한 환경 내 안정한 동작을 위하여 수동적 보호 기능을 가진 피막이 소자 외부를 감싸는 봉지막 전략이 도입되었다. 본 논문에서는 트랜지언트 전자소자의 등장 배경과 분해 거동을 포함한 최근 연구 동향과 작동 환경 내 물 침투를 방지하여 동작 신뢰도를 향상시킬 수 있는 봉지막 전략에 관하여 정리하였다.

• 한국주조공학회지
• /
• 제41권2호
• /
• pp.139-143
• /
• 2021

타이타늄 합금 중 페로-타이타늄은 철강 업계에서 철강과 스테인리스강을 생산하는데 사용되는 주요 첨가물이다. 본 연구에서는 고품질의 페로-타이타늄 합금을 주조하기 위해 경제적인 면을 고려한 저비용 타이타늄 스크랩을 활용하고자 하였다. 먼저 재활용 타이타늄 스크랩의 표면에 형성되어 있는 절삭유 및 불순물을 제거하기 위한 최적의 전처리 공정을 연구하였다. 일반적인 세척 방법인 산이나 유기용제는 세척이 용이하나 환경적으로 문제가 되므로 친환경적인 방법을 고안하여 적용하고자 하였다. 또한, 타이타늄 스크랩을 활용하여 고품질의 페로-타이타늄 잉곳을 제조하고 성분 분석을 통해 불순물과 특성을 상용 소재 규격과 비교 분석하였다.

• The Plant Pathology Journal
• /
• 제37권6호
• /
• pp.580-595
• /
• 2021

Although late blight is an important disease in ecofriendly potato cultivation in Korea, it is highly dependent on the use of eco-friendly agricultural materials and the development of biological control technology is low. It is a necessary to develop an effective biocontrol agent to inactivate late blight in the field. AFB2-2 strain is a gram-positive with peritrichous flagella. It can utilize 20 types of carbon sources, like L-arabinose, and D-trehalose at 35℃. The optimal growth temperature of the strain is 37℃. It can survive at 20-50℃ in tryptic soy broth. The maximum salt concentration tolerated by AFB2-2 strain is 7.5% NaCl. AFB2-2 strain inhibited the mycelial growth of seven plant pathogens by an average inhibitory zone of 10.2 mm or more. Among the concentrations of AFB2-2, 10⁷ cfu/ml showed the highest control value of 85.7% in the greenhouse. Among the three concentrations of AFB2-2, the disease incidence and severity of potato late blight at 10⁷ cfu/ml was lowest at 0.07 and 6.7, respectively. The nucleotide sequences of AFB2-2 strain were searched in the NCBI GenBank; Bacillus siamensis strain KCTC 13613, Bacillus velezensis strain CR-502, and Bacillus amyloliquefaciens strain DSM7 were found to have a genetic similarity of 99.7%, 99.7%, and 99.5%, respectively. The AFB2-2 strain was found to harbor the biosynthetic genes for bacillomycin D, iturin, and surfactin. Obtained data recommended that the B. velezensis AFB2-2 strain could be considered as a promising biocontrol agent for P. infestans in the field.

• 한국재료학회지
• /
• 제33권6호
• /
• pp.257-264
• /
• 2023

To develop a high capacity lithium secondary battery, a new approach to anode material synthesis is required, capable of producing an anode that exceeds the energy density limit of a carbon-based anode. This research synthesized carbon nano silicon composites as an anode material for a secondary battery using the RF thermal plasma method, which is an ecofriendly dry synthesis method. Prior to material synthesis, a silicon raw material was mixed at 10, 20, 30, 40, and 50 wt% based on the carbon raw material in a powder form, and the temperature change inside the reaction field depending on the applied plasma power was calculated. Information about the materials in the synthesized carbon nano silicon composites were confirmed through XRD analysis, showing carbon (86.7~52.6 %), silicon (7.2~36.2 %), and silicon carbide (6.1~11.2 %). Through FE-SEM analysis, it was confirmed that the silicon bonded to carbon was distributed at sizes of 100 nm or less. The bonding shape of the silicon nano particles bonded to carbon was observed through TEM analysis. The initial electrochemical charging/discharging test for the 40 wt% silicon mixture showed excellent electrical characteristics of 1,517 mAh/g (91.9 %) and an irreversible capacity of 133 mAh/g (8.1 %).

• 농업과학연구
• /
• 제50권4호
• /
• pp.713-721
• /
• 2023

Soil acidification challenges global food security by adversely influences soil fertility and agricultural productivity. Carbonized agricultural residues present a sustainable and ecofriendly way to recycle agricultural waste and mitigate soil acidification. We evaluated the effects of organic amendments on lettuce growth and soil chemical properties in two soils with different pH levels. Carbonized rice husk was produced at 600℃ for 30 min and rice husk was treated at 1% (w·w^-1). Carbonized rice husk increased soil pH, electrical conductivity, total carbon content, and nitrogen content compared with untreated and rice husk treatments. Furthermore, this study found that lettuce growth positively correlated with soil pH, with increasing soil pH up to pH 6.34 resulting in improved lettuce growth parameters. Statistical correlation analysis also supported the relationship between soil pH and lettuce growth parameters. The study findings showed that the use of carbonized rice husk increased the constituent elements of lettuce, such as carbon, nitrogen, and phosphate content. The potassium content of lettuce followed a similar trend; however, was higher in acidic soil than that in non-acidic soil. Therefore, improving the pH of acidic soil is essential to enhance agricultural productivity. It is considered advantageous to use agricultural residues following pyrolysis to improve soil pH and agricultural productivity.

• 한국작물학회지
• /
• 제58권4호
• /
• pp.451-458
• /
• 2013

고 기능성 쌀들의 장차 생활습관성질환 맞춤형 즉석밥의 활용 가능성을 검토하고자 고아미, 큰눈쌀, 백진주, 아랑향찰 등 4품종의 쌀 및 쌀가루의 취반적성 및 조리성을 각각 검정하였다. 조 단백질, 조 지질 및 조섬유소 함량 등 영양소 함량은 고아미가 가장 높은 수치를 나타내고 있었다. 백진주와 고아미는 일반품종의 현미 및 백미와 비슷한 양상의 수분흡수율을 보이고, 아라향찰은 $85^{\circ}C$에서 상대적으로 높은 수분흡수율을 보였다. 또한 DSC parameter 중 호화열(${\Delta}H$)은 고아미가 높은 수치를 나타내고 있었으며, 여러 종류의 기능성 쌀 밥 중에서 관능적으로 가장 기호도가 높은 품종은 아랑향찰이었고, 큰눈쌀 및 백진주도 현미상태임에도 불구하고 비교군 백미보다 높은 기호도를 나타내어, 즉석밥을 개발을 위한 품종으로 적합하다고 사료된다.

• 한국환경농학회지
• /
• 제30권1호
• /
• pp.60-67
• /
• 2011

현재 식품의약품안전청에서 고시하고 있는 한약재 중 잔류 농약 분석법에 따라 강활, 박하, 천궁 및 황기 시료 중 endosulfan과 그 분해산물인 endosulfan sulfate를 분석한 결과 많은 간섭물질의 등장과 낮은 회수율 등의 문제점을 확인하였다. 이에 고시된 시험법의 액-액 분배 과정을 대신하여 MDE column을 적용하여 ${\alpha}$-endosulfan 80.3 ~ 93.5%, ${\beta}$-endosulfan 81.0 ~ 100.3%, endosulfan sulfate 80.6 ~ 95.6%의 회수율과 1.1 ~ 3.4%의 변이계수(CV)를 얻었으며 이러한 결과는 잔류농약 분석기준을 만족하였다. MDE column의 사용으로 액-액 분배 과정을 대신하면서 발암가능 물질인 dichloromethane 사용을 배제할 수 있어 분석자의 안전성 향상, 노동력 및 전처리 시간의 절감, 발생되는 폐액 감소, 액-액 분배시 emulsion 현상의 해소, 분석자간의 재현성 양호 등의 이점도 얻을 수 있었다.

• 한국토양비료학회지
• /
• 제49권4호
• /
• pp.355-367
• /
• 2016

Soil salinization refers to the buildup of salts in soil to a level toxic to plants. The major factors that contribute to soil salinity are the quality, the amount and the type of irrigation water used. The presented review discusses the different sources and causes of soil salinity. The effect of soil salinity on biological processes of plants is also discussed in detail. This is followed by a debate on the influence of salt on the nutrient uptake and growth of plants. Salinity decreases the soil osmotic potential and hinders water uptake by the plants. Soil salinity affects the plants K uptake, which plays a critical role in plant metabolism due to the high concentration of soluble sodium ($Na^+$) ions. Visual symptoms that appear in the plants as a result of salinity include stunted plant growth, marginal leaf necrosis and fruit distortions. Different strategies to ameliorate salt stress globally include breeding of salt tolerant cultivars, irrigation to leach excessive salt to improve soil physical and chemical properties. As part of an ecofriendly means to alleviate salt stress and an increasing considerable attention on this area, the review then focuses on the different plant growth promoting bacteria (PGPB) mediated mechanisms with a special emphasis on ACC deaminase producing bacteria. The various strategies adopted by PGPB to alleviate various stresses in plants include the production of different osmolytes, stress related phytohormones and production of molecules related to stress signaling such as bacterial 1-aminocyclopropane-1-carboxylate (ACC) derivatives. The use of PGPB with ACC deaminase producing trait could be effective in promoting plant growth in agricultural areas affected by different stresses including salt stress. Finally, the review ends with a discussion on the various PGPB activities and the potentiality of facultative halophilic/halotolerant PGPB in alleviating salt stress.