• 제목/요약/키워드: 상자성 효과

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Thermal Effects on Stoichiometric LiTaO3 Single Crystal (정비조성 LiTaO3 단결정에 대한 열처리 효과)

  • Yeom, T.H.;Lee, S.H.
    • Journal of the Korean Magnetics Society
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    • v.15 no.3
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    • pp.177-180
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    • 2005
  • Ferroelectric $LiTaO_3$ single crystals, grown by the Czochralski method, were thermally treated at temperature $1000^{\circ}C\;and\;1100^{\circ}C$. Electron paramagnetic resonance (EPR) study of stoichiometric $LiTaO_3$ and thermally treated $LiTaO_3$ crystals has been investigated by employing an X-band spectrometer. From the $Fe^{3+}$ EPR spectra, it turned out that there is no change of site location and local site symmetry around $Fe^{3+}$ impurity ion between stoichiometric and thermally treated $LiTaO_3$ single crystals. We confirmed that the ionic state of $Fe^{3+}$ ion changed after thermal treatment. The EPR parameters of $Fe^{3+}$ ion in $LiTaO_3$ single crystals are determined with effective spin Hamiltonian.

Research Trend and Prospect in Ferromagnetic Superconductor (강자성 초전도체의 연구동향과 전망)

  • Han, Sang-Wook
    • Journal of the Korean Magnetics Society
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    • v.22 no.2
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    • pp.66-72
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    • 2012
  • The findings of ferromagnetic superconductor have attracted much attention not only for fundamental research to investigate how the antagonistic properties of ferromagnetism and superconductivity coexist peacefully but also for potential technological applications. Firstly, in order to help for understanding the ferromagnetic superconductor, I have explained the orbital and paramagnetic pair-breaking effects of magnetic field, which breaks the superconducting Cooper pairs. In addition to such effects of magnetic field, the singlet Cooper pairs become unstable upon going through the ferromagnetic materials by the proximity effect. The proximity effect occurs at the interface of thin films composing of superconductor and ferromagnet and leads to have very short penetration depth of Cooper pairs. However, a type of odd-frequency triplet in comparison with the singlet could be very stable and has a longer effective depth. It needs to be explored for the innovative spintronic devices. Finally, various ferromagnetic superconductors coexist and the lower-dimensional materials under the Quantum confinement effect have been introduced.

Freshness Extension of Tomatoes by Packaging Methods (포장 방법에 따른 토마토의 품질변화)

  • 박형우;박종대;김동만
    • Food Science and Preservation
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    • v.6 no.3
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    • pp.255-259
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    • 1999
  • This study was measured weight loss, total ascorbic acids, titratable acidity and soluble solids contents to investigate the effect of EPS(expended polystrene foam) box, double wall corrugated paperboard box and LDPE film pouches during storage at 25oC. The rate of weight loss was 5.9% in corrugated paperboard box after 7 days, but those of 20LD, 40LD film and EPS box were 1.1, 1.0, and 1.1% , respectively. Total ascorbic acid content of EPS box was 20% higher than that in corrugated paperboard box, but the obvious differents were not observed among the LDPE film pouches and EPS box. The titratable acidity was decrease during storage, but total soluble solids content was increase. Overall appearences of LDPE pouches and EPS box were better than those of corrugated paperboard box.

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Reversed Elongation Effect on Boxes (상자 모양 용기에서의 역전된 신장 효과)

  • Kim, Dong Eun;Song, Hyun Jin;Sohn, Young Woo
    • Science of Emotion and Sensibility
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    • v.19 no.2
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    • pp.19-26
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    • 2016
  • Previous research has shown that people perceive the larger volume for tall and lean cylindrical containers over short and wide containers of the same volume (e.g., Raghubir & Krishna, 1999; Wansink & Van Ittersum, 2003). The present research demonstrated that this elongation effect is reversed for boxes, presumably due to the affordance of the boxes. Two studies showed that participants judge short and wide boxes as having larger volume than long and lean boxes of the same volume. This effect replicated through two types of presentation formats (drawing, Study1; actual object, Study2) when the choice between two boxes was forced (Study 1) and not (Study 2). The results also replicated among participants residing in the U.S. (Study 1) and participants residing in Korea (Study 2). The reversed elongation effect held for liquid materials in general (water, Study 1; drinks, Study 2). Theoretical and managerial implications are discussed.

참외.포도.방울토마토의 고품질 유통을 위한 저온유통용 골판지 포장상자 개선에 관한 연구

  • Lee, Won-Ok;Yoon, Hong-Sun;Lee, Hyun-Dong;Jung, Hoon;Cho, Kwang-Hwan;Kim, Man-Soo
    • Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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    • 2003.04a
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    • pp.139-139
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    • 2003
  • 원예작물은 수확 후 여러 가지 요인에 의해 품질이 저하되어 상품성을 잃게되는데, 특히 수확 후 품온상승에 의해 호흡작용이 왕성해져 품질변화를 촉진하게 된다. 그러므로 수확 후 품온을 가능한 한 빠르게 낮추어 신선도를 유지하기 위한 예냉, 저온저장, 저온수송기술등 저온유통시스템을 활용하는 것이 매우 필요하다. 저온유통시스템을 효과적으로 활용하기 위해서는 냉기의 순환이 원활하여 냉각효율이 좋고 파손의 위험과 물류비용을 줄일 수 있는 포장상자의 구조에 대한 연구가 필요하다. 포도, 방울토마토, 참외의 소비형태는 핵가족화와 더불어 신선 고품질의 농산물을 소량 구매하는 소비패턴으로 변화하면서 저온유통 및 소포장을 위한 포장형태의 개선이 요구되고 있다. 따라서 예냉.저온유통에 적합한 포장상자를 개발하기 위하여 연구소, 농협중앙회, 상자제작회사, 포장디자인 업체, 산지농협 작목반이 개발협의체를 구성하여 참외, 포도, 방울토마토의 저온유통용 골판지 상자를 개발하여 압축강도 및 냉각시험을 실시하여 소비지에 시범 보급하였다. 1. 참외 포장상자는 3kg용 상부 개방형 골판지상자로써 손잡이를 부착하고, 포장상자 상부에 덮개용 필름을 부착하였다. 제작된 상자의 압축강도는 저온유통 후 에도 안전압축강도 이상인 343kgf의 압축강도를 나타냈고, 냉각효율도 기존상자에 비하여 높게 나타났다. 또한 개발된 상자를 사용하여 시중에 출하할 경우 기존 5kg 상자에 비하여 8%이상의 부가가치를 높일 수 있었다. 2. 포도 포장상자는 소비자 기호도를 충족하고 다층적재시 손상을 방지하기 위하여 내용물을 1단 적재하고 상자를 개방형으로 하여 덮개용 필름을 부착하므로써 소비자가 내용물을 확인할 수 있도록 하고, 상자의 압축강도는 소비지까지 유통이 완료된 후 에도 수직압축강도가 400kgf이상으로 안전압축강도 보다 높아 저온에서 안전하게 유통할 수 있었다. 또한 개발된 상자를 사용하여 시중에 출하할 경우 기존 5kg 상자에 비하여 2kg상자는 21%, 4kg상자는 12%이상의 부가가치를 높일 수 있었음. 3. 방울토마토 포장상자는 외포장 상자를 4kg용 상부 개방형 골판지상자를 사용하고, 내포장상자는 500g용 PET용기를 사용하여 1상자에 8개의 내포장상자가 적재될 수 있도록 제작하였다. 제작된 외포장상자의 압축강도는 저온유통후에도 320kgf으로 안전압축강도보다 높게 나타났고, 파랫트 적재효율도 96%이상으로 나타나 물류의 효율성을 높일 수 있었다. 개발된 상자를 사용하여 시중에 출하할 경우 기존 산물형태의 4kg용 상자에 비하여 500g 내포장상자에 출하할 경우 20%이상의 부가가치를 높일 수 있었다.

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Development of Corrugated Paperboard Box for Agricultural and Fishery Products (농수산물 유통용 포장상자 개선)

  • Park, Hyung-Woo;Ha, Young-Sun;Kim, Su-Il
    • Korean Journal of Food Science and Technology
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    • v.21 no.2
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    • pp.238-241
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    • 1989
  • Double wall corrugated paperboard box are almost used for package of agricultural and fishery products in Korea. Flaps of the double wall corrugated paperboard box are consist of the three linerboard and two corrugating medium. But these flaps which are not affected to the compression strength for storage and distribution results in the reasonable cost-up of the packed box. Compared the strengths and economical evaluations between double wall and single wall corrugated paperboard box results as follows. Compression strength of single wall box is higher 49.3% to 98.0% than that of the double wall corrugated paperboard box and its cost are down 5% to 8%. Effect of the cost down on the saving materials of flap and corrugating medium is 13.9%.

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The NMRD Profiles of Ultrasmall Superparamagnetic Iron Oxide: Computer Simulation

  • 장용민;황문정;강덕식
    • Proceedings of the KSMRM Conference
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    • 2001.11a
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    • pp.107-107
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    • 2001
  • 목적: 초상자성 nano-particle 조영제의 자기이완효과에 관한 out sphere 기전에 기초하여 각각의 자기장의 세기에서 T1/T2 자기이완율을 나타내는 NMRD profile을 수치적으로 simulation 하는 프로그램을 개발하고자 하였다. 대상 및 방법: 초상자성 nano-particle 조영제의 경우 초상자성 물질을 생체적합성 고분자로 표면 coating하기 때문에 상자성 조영제와는 달리 전적으로 "out sphere"기여도만을 고려하였고 또한 초상자성 물질의 경우 자기적 에너지의 크기가 매우 크기 때문에 상자성 조영제의 기전에서 사용되는 "low field"근사를 사용할 수 없으므로 Brillouin 함수로 표현되는 총자화에 대한 표현을 적용하였다. nano-particle내에 포함된 Fe 원자수에 따른 T1 및 T2 NMRD Profile과 온도에 따른 T1 및 T2 NMRD Profile 그리고 초상자성 nano-particle size에 따른 T1 및 T2 NMR Profile을 PC (CPU=800 Mhz, memory=128 MB) 환경하에서 symbolic computation tool 인 MathCad (MathCad, USA)를 사용하여 구현하였다.

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Freshness Extension of ‘Fuji’Apple to Packaging materials (포장재가 ‘후지’사과의 신선도에 미치는 영향)

  • 박형우;박종대;김동만;최주섭
    • Food Science and Preservation
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    • v.8 no.4
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    • pp.345-350
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    • 2001
  • This study was measured weight loss, total ascorbic acid, titratable acidity, and soluble solids content to investigate the effect of EPS(expanded polystyrene foam, foaming rate 55 times V/W) box, LDPE film pouches and double wall corrugated fiberboard box during storage at 20$\^{C}$. Weight loss of apple packed with corrugated paperboard box after 40 days storage was 5.7%, arid those of LDPE, CE(zeolited coated film) film and EPS box were 0.2-0.5%. Ascorbic acid content of apple packed with LDPE, CE, EPS was higher than that of control. Titratable acidity and total soluble solid content of control were changed 40% and 10%, but the EPS were changed 27% and 4%, respectively. Overall appearances of ‘Fuji’apple packed with LDPE, CE and EPS were better than that of control.

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Freshness Preserving of Table Grape using Corrugated Paperboard Box Laminated with Functional MA Film (기능성 골판지 상자로 포장한 포도의 신선도 유지효과)

  • 박형우;박종대;김태규;김기정
    • Food Science and Preservation
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    • v.5 no.4
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    • pp.331-334
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    • 1998
  • Weight loss of table Grape packed with control(Corrugated paperboard box), LDPE, CE(MA film masterbatched by ceramic powder treated cemical reagent) and FC box(laminated by CE film pouch) at 25 C after 10 days were 5.6%, 0.4%, 0.6%, and 0.7%, respectively. Weight loss of control was 7.29times higher than that of FC box. Total ascorbic acid content(TAA) of table grape after 10 days was 3.42 mg% for control, was 5.33 for LDPE and 5.14mg% for CE, 4.98mg% for FC. TAA of LDPE and CE showed to higher than that of control, especially TAA of FC was 33% higher than that of control. Titratable acid of LDPE and CE was high compare to control, and acidity of FC was 6% higher than that of control. References in overall appearance of LDPE, CE and FC were better than that of control. Corrugated paperboard box(FC) laminated with functional MA film showed to be able to used as packaging box of table grape.

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Polarization dependence on Cavity Ringdown Spectroscopy (공동 광자감쇠 분광학에서의 편광의존성)

  • 김재완;한재원
    • Proceedings of the Optical Society of Korea Conference
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    • 2000.08a
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    • pp.216-217
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    • 2000
  • 상자성을 갖는 분자에 대한 분광학 연구에서는 제만(Zeeman) 효과로 생기는 이색성을 이용한 magnetic rotation spectroscopy (MRS)가 널리 사용되고 있다.$^{(1)}$ MRS가 일반적인 흡수 분광법에 비해 더 민감한 측정을 할 수 있기는 하지만 사용하는 편광기의 extinction ratio에 의해 감도가 한정된다. MRS의 감도를 높이는 방법으로는 광경로를 길게 만드는 것을 고려할 수 있다. 일반적으로 공진기 광자감쇠 분광학(Cavity Ring-Down Spectroscopy, CRDS)은$^{(2)}$ 높은 반사율을 갖는 거울을 사용해서 수 km 이상의 광 경로를 만들기 때문에 감도가 높다. (중략)

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