• 제목/요약/키워드: Nd seed

검색결과 97건 처리시간 0.031초

TSMG법에 의한 RE-123계 초전도 단결정 제조에 미치는 seed의 영향 (Effect of seed on the TSMG processing of RE-123 superconductor)

  • 오용택;신동찬;한상철;성태현
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2003년도 추계학술대회 논문집 Vol.16
    • /
    • pp.59-62
    • /
    • 2003
  • This study investigated the phase transformation of the $REBa_2Cu_3O_{7-x}$ (RE=Nd, Gd, By) superconductor, and CCT (Continuous-Cooling-Transformation) along with the TTT (Time-Temperature-Transformation) diagrams are suggested according to the isothermal and continuous cooling heat-treatments. According to result of fabricated single crystal of RE-123 superconductor through TSMG method based on phase transformation neted among heat treatment process, when the ionic radius elements was decreased, RE-211 phase was well-distributed. According to result that examine about seed of pretreatment effect of TSMG method, magnetic hysteresis improved when preprocess among oxygen atmosphere in same seed. and used after. Effect of miscut expressed good superconducting special quality in case miscut uses big seed.

  • PDF

토양시드뱅크에 의한 식생복원 가능성에 관한 연구 (A Study on the Potential Contribution of Soil Seed Bank to the Revegetation)

  • 고정현
    • 한국환경복원기술학회지
    • /
    • 제10권6호
    • /
    • pp.99-109
    • /
    • 2007
  • The main objectives of this comparative study were 1) to compare the floristic similarity of species composition between the extant vegetation and seedlings from soil seed bank and 2) to quantify the potential contribution of soil seed bank to revegetation of forest in a constructed area, which is called "ecological impact mitigation" in conjunction with the power plant extension. Forest topsoil of seven plots was collected from the surface soil after measurements were taken on the ground vegetation in each plot. A greenhouse experiment was conducted and monitored to analyze the germination potential of soil seed bank. The forest topsoil was spread on plastic trays ($0.7m^2{\times}7$) filled with a 5cm layer of sterilized potting mix. The results of monitoring for 2 years in a greenhouse were as follows : 1) seedlings of soil seed bank per 4.9$m^2$ were 1,269 with 36 species (1st year) and 2,615 with 25 species (2nd year). 2) 38${\pm}$8% of the flora species were germinated from soil seed bank. It can be concluded that the use of soil seed bank would be effective to promote establishment of diverse species and vegetation. However, it behooves to continue monitoring on succession of vegetation and pursue revegetation with other methods for ecological restoration. Finally, adequate topsoil deposit and gathering methods should be studied properly.

녹색 레이저 발진용 NYAB 단결정 성장 (Growth of Nd : YAl3(BO3)4 Single Crystal for Green Laser)

  • 최덕용;정선태;박승익;정수진
    • 한국세라믹학회지
    • /
    • 제32권2호
    • /
    • pp.270-278
    • /
    • 1995
  • Nd : YAl3(BO3)4 (NYAB) single crystal has been developed for green laser. In this experiment, we found K2O/3MoO3/0.5B2O3 to be a suitable flux for NYAB crystal growth, and grew NYAB crystal by TSSG method using this flux. By varying the cooling rate of solution, seed orientation, and rotation speed, the effects of these growth conditions on the crystal quality and its morphology were examined. Suitable growth conditiions were a cooling rate slower than 2.4$^{\circ}C$/day, the rotation speed of 25~30 rpm, and the <001> seed orienttion. The phases of grown crystal, coexisting and volatile materials were investigated by X-ray diffraction. In addition, the possiblity of laser action was examined by UV analysis.

  • PDF

Nd:YLF 레이저 펄스의 재생식 증폭 (Regenerative amplification of pulses in Nd:YLF)

    • 한국광학회지
    • /
    • 제3권1호
    • /
    • pp.37-42
    • /
    • 1992
  • 공진기 내에서 종자펄스를 여러번 왕복시키며 증폭시키는 재생식 증폭기의 설계 및 동작톡성에 대하여 연구하였다. 기계적, 열적 요동에 대하여 안정된 작동을 하도록 Nd:YLF를 레이저 매질로 사용하고, 광학 부품에 미치는 에너지 밀도를 최소화할 수 있도록 오목거울과 볼록거울로 구성된 증폭기 공진기를 설계, 제작하였다. 종자펄스로는 펄스 폭 40ps, 에너지 100pJ, 파장 1,053.$\mu$m인 Nd:YLF 레이저 펄스를 사용하여 재생식 증폭기로 최대 반복률 3.5kHz에서 1mJ의 안정된 펄스를 얻었으며, 최대 출력은 5mJ이었다.

  • PDF

수소화 표면 개질이 나노다이아몬드 seed 입자의 분산 및 핵형성 밀도에 미치는 영향 (Effect of hydrogenation surface modification on dispersion and nucleation density of nanodiamond seed particle)

  • 최병수;전희성;엄지훈;황승구;김진곤;조현
    • 한국결정성장학회지
    • /
    • 제29권6호
    • /
    • pp.239-244
    • /
    • 2019
  • 수소 분위기 열처리 및 수소 플라즈마 처리의 두 가지 수소화 표면개질을통해 나노다이아몬드 seed 입자의 분산 향상 및 평탄한 초미세 나노결정질 다이아몬드 박막증착을 위한 핵형성 밀도 향상을 확보하였다. 수소화 처리 이후 나노다이아몬드 입자 표면의 탄소-산소 및 산소-수소 결합기가 탄소-수소 결합기로 전환되는 화학적 표면개질이 진행되었고 Zeta 전위가 증가하였다. 분산도 향상에 따라 나노다이아몬드 응집체 크기가 현저하게 감소하였고 핵형성 밀도는 크게 증가하였다. 600℃, 수소분위기에서 열처리 이후 나노다이아몬드 평균 입자 크기가 3.5 ㎛에서 34.5 nm로 크게 감소하였고, seeding 된 Si 기판 표면에서 ~3.9 × 1011 nuclei/㎠의 매우 높은 핵형성 밀도를 확보하였다.

Assessment Items of Outdoor Environment through Analysis of SITES - Focused on the Comparison with G-SEED and LEED -

  • Lee, Hyung-Sook
    • KIEAE Journal
    • /
    • 제14권4호
    • /
    • pp.11-18
    • /
    • 2014
  • Although assessing outdoor environment and green space in terms of sustainability and environmental performance is perceived as an important issue, most existing green building certification systems are more focused on buildings and indoor environment. Recently, the Sustainable Site Initiatives (SITES) has been developed by American Society of Landscape Architecture in order to evaluate sustainability of site development and outdoor environment. Separate from LEED, the SITES are increasingly receiving attentions as a reliable certification system in the United States. As a preliminary study to develop the items of outdoor environmental assessment, the present study is purposed to analyze the assessment items, grading system and applicability of SITES for better understanding on the system. Also it was compared to existing green building certification criteria, including G-SEED, LEED-NC, and LEED-ND in order to investigate similarities and discrepancies. The results would provide insights and basic data to improve assessment items for outdoor environment of G-SEED.

추작 마령서의 파종기, 파종법 및 최아법이 발아 생육에 미치는 영향 (Effects of the periods and the methods of seeding and the seed bed locations on the sprouting of seed pieces of fall grown potatoes)

  • 강신원
    • 한국작물학회지
    • /
    • 제8권1호
    • /
    • pp.121-127
    • /
    • 1970
  • 1. 추작 마영서 단종 적순는 7月21견경으로 보였다. 2. 배수가 양호한 곳에서는 직파해도 발아에 지장이 없었다. 3. 양지(야외)최아가 음령소 최아보다 싹이 훨신 건실했다.

  • PDF

벼 갈색잎마름병균(Gerlachia oryzae)의 종자감염과 종자감염이 벼종자 및 유묘에 미치는 피해 (Seed Infection and Damage to Rice Seeds and Seedlings by Seed-Borne Gerlachia oryzae)

  • 김완규;박종성;유승헌
    • 한국응용곤충학회지
    • /
    • 제23권2호
    • /
    • pp.126-131
    • /
    • 1984
  • 1. 영남작물시험장, 호남작물시험장 및 충남농촌진흥원에서 분양받은 18개의 벼종자시료와 충남지역 일반농가에서 수확한 8개의 벼종자시료 등 모두 26개의 종자시료를 공시하여 표준습지법으로 조사하였던 바 21종의 균류가 검출되었으며, 벼 갈샐잎마름병균(Gerlachia oryzae)은 22개의 벼 종자시료에서 $1.0\~45.0\%$의 범위로 검출되었다. 2. 종자전염성 G. oryzae의 효과적인 검출방법을 찾기 위하여 표준습지법, 냉동습지법, 물한천법 등으로 비교 조사한 결과, 냉동습지법에서 검출율이 가장 높았다. 3. 벼종자의 각 부위를 무균적으로 분리하여 부위별로 G. oryzae의 감염여부를 표준습지법으로 조사한 결과, 벼 종자의 껍질에서 가장 많이 검출되었으며, 심하게 이병된 종자는 배유 및 종피 뿐 만 아니라 배에 까지 감염되어 있었다. 4. G. oryzae에 감염된 벼 종자를 파종하여 심하게 이병된 종자는 종자부패 및 묘입고를 일으켰으며, 약하게 이병된 종자는 초엽, 1엽, 2엽에 갈색의 병징감염을 초래하였다.

  • PDF

Grape seed extract (Vitis vinifera) partially reverses high fat diet-induced obesity in C57BL/6J mice

  • Park, Su-Hui;Park, Tae-Sun;Cha, Youn-Soo
    • Nutrition Research and Practice
    • /
    • 제2권4호
    • /
    • pp.227-233
    • /
    • 2008
  • The aim of the present study was to assess the anti-obesity effects of grape seed extract (GSE) supplement in C57BL/6J mice. Thirty mice were divided into three groups; normal diet control group (ND), high fat diet control group (HD) and high fat diet plus grape seed extract supplemented group (HD+GSE). Results were as follows: 1. GSE supplement reduced the weight gain in mice fed high fat diets; epididymal and back fat weights, were lower compared to non-supplemented HD group. 2. Blood lipid concentrations were lower in the HD+GSE group than in the HD group. Serum HDL-C concentrations were higher in the HD+GSE group compared with the other groups. 3. The concentrations of acid-insoluble acylcarnitines, (AIAC) in serum and liver were higher in the HD+GSE group than in the HD group. 4. GSE supplementation increased mRNA levels of lipolytic genes such as carnitine palmitoyltransferase-l (CPT-1) and decreased mRNA levels of lipogenic genes such as acetyl CoA carboxylase (ACC). These findings suggest that grape seed extract supplements in high fat diet might normalize body weight, epididymal and back fat weights, lipid concentrations, and carnitine levels through controlling lipid metabolism.

광펄스 파라미터 가변 LD를 이용한 복합형 DPSSL 개발 (Development of a Hybrid DPSSL with a Pulse Parameter Variable LD Seed)

  • 노영철;신우진;유봉안;이영락;정창수
    • 한국정밀공학회지
    • /
    • 제27권10호
    • /
    • pp.7-13
    • /
    • 2010
  • We report a hybrid DPSSL with a pulse parameter variable LD seed, all-fiberized polarization-maintained pulsed Yb-doped fiber preamplifier chains, and a bulk Nd:$YVO_4$ power amplifier. Pulse parameter of LD seed was controlled by direct current modulation. The hybrid DPSSL generates 1064 nm laser pulses with an average power of 40W, a pulse duration of 20-40ns, and a repetition rate of 100-500kHz.