• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.253.1-253.1
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• 2014

Plasma technology has been widely used for decontamination, differentiation, and disease treatment. Recently, studies show that plasma has effects on increasing seed germination and plant growth. In spite of increasing number of studies about plasma effects, the interaction between plasma and plants has been rarely informed. In this study, we have analyzed the effects of nonthermal atmospheric pressure plasma on seed germination and growth of coriander (Coriandum sativum), a medicinal plant. We used to Ar, air, and N2 plasma on seed as feeding gases. Plasma was discharged at 0.62 kV, 200 mA, 9.2 W. Seed germination was increased over time when treated with N2 based DBD plasma for exposure times of 30 seconds and 1 minute, everyday. After 7 days, about 80~100% of seeds were germinated in the treatment with N2 based DBD plasma, compared to control (about 40%, only gas treated seeds). In order to elucidate the mechanism of increased germination, we have analyzed characteristics of changes in plant hormones and seed surface structure by SEM.

• 한국세라믹학회지
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• 제27권6호
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• pp.808-816
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• 1990

The thermal behavior of transformation and characteristics of seeded sample powders prepared by simultaneous $\alpha$-Al2O3 seed addition with water on the Al-sec-butoxide hydrolysis were studied. $\alpha$-Al2O3 seed particles are shown to act as nuclei for transformation of $\theta$-to $\alpha$-Al2O3 and to result in an increase in thetransformation kinetics and lowering of the transformation temperature by as much as 143$^{\circ}C$. Simultaneous seed addition on the hydrolysis resulted in uniform dispersin and creation of nucleation site on seed surface and only 0.1wt% seeding lowered the transformation temperature by as much as 115$^{\circ}C$. For 3wt% seed addition, $\alpha$-Al2O3 single phase was obtained at 95$0^{\circ}C$ for 100 minutes and the specific surface area of products were lowered to 11.9$m^2$/g as compared with that of $\alpha$-Al2O3 powder prepared without seed at 115$0^{\circ}C$ ; 15.1$m^2$/g due to depression of vermicular structure growth.

• 한국약용작물학회지
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• 제9권4호
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• pp.259-264
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• 2001

황기 종자의 구조적 특성을 알아보고, 저장기간 및 온도와 함량 변화와 이들 요인이 발아에 미치는 영향을 구명하고자 실험한 결과를 요약하면 다음과 같다. 1. 황기의 경실 종자는 배꼽과 주공의 중앙 부분의 갈라진 선이 뚜렷하지 않고 찌그러진 것처럼 보였으며, 종피와 배의 간격이 크고 분리되어 있는 것처럼 보였다. 2. 저장기간이 길어지면 경실 종자가 많아지고 활력이 낮아졌으며 특히 28개월 이상 저장했을 때 흡수종자는 활력이 낮았으나 경실 종자는 변화가 적었다. 3. 저장기간이 길어질수록 Ca 함량이 증가하는 경향이었다.

• 한국전기전자재료학회논문지
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• 제26권12호
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• pp.863-866
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• 2013

SiC crystal ingots were grown on 6H-SiC dual-seed crystals with different surface roughness and different seed orientation by a PVT (Physical Vapor Transport) method. 4H and 15R-SiC were grown on seed crystal with high root-mean-square (rms) value. The polytype of grown crystal on the seed crystal with lower rms value was confirmed to be 6H-SiC. On the other hand, all SiC crystals grown on seed crystals with different seed orientation were proven to be 6H-SiC. The surface roughness of seed crystals had no effect on the crystal structure of the grown crystals. However, the crystal quality of 6H-SiC single crystals grown on the on-axis seed were revealed to be slightly better than that of 6H-SiC crystal grown on the off-axis seed.

• 한국식품과학회지
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• 제31권6호
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• pp.1410-1414
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• 1999

Durian 종자 전분의 입자크기범위는 약 $2.0-10.0\;{\mu}m$ 이었으며 구형과 다각형의 형태를 갖고 있었다. Durian종자, 옥수수, 고구마, 감자전분의 아밀로오스 함량은 28.3%, 27.5%, 20.3% 및 21.7%이었다. Durian 종자, 옥수수, 고구마, 감자전분의 blue value는 0.370, 0.368, 0.332 및 0.338이었으며, 알칼리도는 7.39, 9.02, 7.08 및 5.43이었다. Durian 종자 전분의 팽윤력과 용해도는 감자전분보다 낮았다. Durian 종자자전분의 X-선 회절도에 의한 결정성은 곡류전분과 같은 A형이었다. RVA로 측정한 durian 종자 전분의 호화개시온도 $(76.6^{circ}C)$는 옥수수$(73.0^{circ}C)$, 고구마$(72.3^{circ}C)$, 감자전분 $(70.2^{circ}C)$보다 높았으며 breakdown은 낮은 반면 setback은 높았다.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• 제4권1호
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• pp.28-42
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• 2023

Seed dispersal supports community structure, maintains genetic connectivity across fragmented landscapes, and influences vegetation assemblages. In the Philippines, only two seed dispersal studies have compared different dispersal agents. We examined the seed dispersal patterns of water, wind, birds, and bats in the Caliraya Watershed, Philippines. We aimed to determine the floral species that were dispersed and how the forest characteristics influenced seed dispersal. By running seed rain traps and drift litter collection from March to June 2022, we analyzed 14,090 seeds in a privately owned study site within the watershed. Water did not exclusively disperse any species and acted as a secondary disperser. Seed density (seeds/trap) was significantly higher for bird-dispersed (n=166) and bat-dispersed (n=145) seeds than for wind-dispersed (n=79) seeds (One-way analysis of variance [ANOVA]: F_2,87=16.21, P<0.0001). Species number (species/trap) was significantly higher for bird-dispersed (n=3.7) and bat-dispersed (n=3.9) seeds than for wind-dispersed (n=0.2) seeds (One-way ANOVA: F_2,87 =16.67, P<0.0001). Birds dispersed more species because they are more diverse and access a wider variety of fruits, unlike bats. Birds and bats target different fruits and provide separate seed dispersal services. Generalized linear model analyses revealed that the number and basal area of fleshy fruit trees most strongly influenced the bird seed dispersal patterns. Therefore, we recommend a three-way approach to restoration efforts in the Caliraya Watershed: (1) ensure the presence of fleshy fruit trees in restoration zones, (2) assist the establishment of mid-successional and wind-dispersed trees, and (3) intensify the conservation efforts for both flora and faunal diversity.

• 공업화학
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• 제7권4호
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• pp.777-786
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• 1996

Seed 중합 방법에 의하여 단분산성 다공의 폴리아크릴로니트릴-에틸렌글리콜 디메타크릴레이트 (PAN) 고분자 마이크로 겔이 제조되었다. PAN 마이크로 겔의 물리적인 특성을 모노머/seed와 희석제/모노머의 비율, 가교제의 농도 및 희석제의 종류에 따라 연구하였다. PAN 마이크로 겔의 입도 분포는 모노머/seed의 비율이 50 이하 일 때 단분산성을 나타냈으며, 가교제의 농도가 증가할수록 입자 내부의 미소 구체 (microsphere)의 크기가 작아져 더욱 밀집된 형태를 나타내기 때문에 입자의 비표면적이 증대되었다. 또한 희석제로 톨루엔을 사용하고 희석제/모노머의 비율이 1.0일 때 입자표면의 세공이 가장 발달되었다.

• Nuclear Engineering and Technology
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• 제55권8호
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• pp.2734-2741
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• 2023

Brachytherapy is a special case of radiotherapy. It should be arranged according to some principles in medical radiation applications and radiation physics. The primary principle is to use as low as reasonably achievable dose in all ionizing radiation applications for diagnostic and therapeutic treatments. Dosimetric distributions are dependent on radioactive source properties and radiation-matter interactions in an absorber medium such as phantom or tissue. In this consideration, the geometrical structure and material of the seed capsule, which surrounds a radioactive material, are directly responsible for isodose profiles and dosimetric functions. In this study, the radiometric properties of capsule material were investigated on dose distribution in a water phantom by changing its nuclear properties using the EGSnrc Monte Carlo (MC) simulation code. Effective atomic numbers of hypothetic mixtures were calculated by using different elements with several fractions for capsule material. Model 6711 brachytherapy seed was modeled by EGSnrc/Dosrcnrc Code and dosimetric functions were calculated. As a result, dosimetric parameters of hypothetic sources have been acquired in large-scale atomic number. Dosimetric deviations between the data of hypothetic seeds and the original one were analyzed. Unit dose (Gy/Particle) distributions belonging to different types of material in seed capsule have remarkably differed from the original capsule's data. Capsule type is major variable to manage the expected dose profile and isodose distribution around a seed. This study shows us systematically varied scale of material type (cross section or effective atomic number dependent) offers selective material usage in production of seed capsules for the expected isodose profile of a specific source.

• Bulletin of the Korean Chemical Society
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• 제28권12호
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• pp.2283-2287
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• 2007

Amyloid fibril formation of amyloid β/A4 protein (Aβ) is critical to understand the pathological mechanism of Alzheimer's disease and develop controlling strategy toward the neurodegenerative disease. For this purpose, dequalinium (DQ) has been employed as a specific modifier for Aβ aggregation and its subsequent cytotoxicity. In the presence of DQ, the final thioflavin-T binding fluorescence of Aβ aggregates decreased significantly. It was the altered morphology of Aβ aggregates in a form of the bundles of the fibrils, distinctive from normal single-stranded amyloid fibrils, and the resulting reduced β-sheet content that were responsible for the decreased fluorescence. The morphological transition of Aβ aggregates assessed with atomic force microscope indicated that the bundle structure observed with DQ appeared to be resulted from the initial multimeric seed structure rather than lateral association of preformed single-stranded fibrils. Investigation of the seeding effect of the DQ-induced Aβ aggregates clearly demonstrated that the seed structure has determined the final morphology of Aβ aggregates as well as the aggregative kinetics by shortening the lag phase. In addition, the cytotoxicity was also varied depending on the final morphology of the aggregates. Taken together, DQ has been considered to be a useful chemical probe to control the cytotoxicity of the amyloid fibrils by influencing the seed structures which turned out to be central to develop therapeutic strategy by inducing the amyloid fibrils in different shapes with varied toxicities.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 춘계학술대회 논문집 초전도 자성체 연구회
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• pp.55-58
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• 2003

FeMn based spin valves often consist of a NiFe/FeMn/NiFe trilayer structure. We have investigated the evolution of exchange bias at the bottom and top interfaces in the NiFe(5nm)/FeMn(x)/NiFe(5nm) trilayer structure as a function of FeMn thickness in the range 3 nm to 30 nm. The XRD results indicate (111) textured growth for NiFe and FeMn layers. The magnetization studies using VSM show two hysteresis loops corresponding to the bottom NiFe seed layer and top NiFe layers with greater bias for the bottom NiFe layer, for FeMn thickness equal to and above 5 nm. The larger exchange bias for the bottom seed layer is confirmed by the surface sensitive MOKE hysteresis loop measurements which show gradual weakening of the MOKE hysteresis loop for the bottom NiFe layer with increasing FeMn thickness. The observed large exchange bias in a spin valve structure is usually attributed to the pinning NiFe layer on top of the FeMn layer, even when a NiFe seed layer of a few nm thickness is present, whereas, in reality it may be arising from the bottom seed layer, as shown by the present study.