• 제목/요약/키워드: SANS

검색결과 85건 처리시간 0.029초

나노구조 분석을 위한 하나로 40m 소각중성자산란장치 개발 (Development of the 40m SANS Instrument at HANARO for Nanostructure Characterization)

  • 최성민;김태환;이지환;한영수;이창희
    • 한국진공학회지
    • /
    • 제14권3호
    • /
    • pp.126-131
    • /
    • 2005
  • 소각중성자산란 (Small-angle neutron scattering, SANS)은 물질의 내부 나노구조 분석에 매우 중요한 실험방법론이다. 본 논문에서는 30MW HANARO 연구용 원자로의 냉중성자 연구시설에 설치하기 위하여 한국과학기술원과 한국원자력연구소가 공동으로 개발 중인 40m SANS장치의 개념설계 결과를 보고한다. 장치의 설계 최적화를 위한 전산모사를 수행하였으며, 이를 바탕으로 40m SANS 장치의 주요설계 인자를 결정하였다. 40m SANS 장치의 가능한 Q-range는 $0.0005\;\AA^{-1}-1.0\AA^{-1}$ 이며, 이는 세계 최고 수준의 SANS Q-range에 해당된다. 각 Q-range에 따른 시료위치에서의 중성자 속을 계산하였으며 전산모사에 사용된 냉중성자원이 구현될 시 세계적 수준의 값을 얻을 수 있을 것으로 예상된다.

Control of Block Copolymer Microdomain: In-Situ and Real-Time SANS Studies of Polymerization-Induced Self-assembly of Block Copolymer Microdomain Structure

  • Koizumi, Satoshi;Yamauchi, Kazuhiro;Hasegawa, Hirokazu;Tanaka, Hirokazu;Motokawa, Ryuhei;Hashimoto, Takeji
    • 한국고분자학회:학술대회논문집
    • /
    • 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
    • /
    • pp.71-72
    • /
    • 2006
  • We investigated a simultaneous living anionic polymerization process of isoprene (I) and 4styrene-d_8$ (S) in $benzene-d_6$ as a solvent with sec-buthyllithium as an initiator into polyisoprene(PI)-block-poly($styrene-d_8$)(PS) and the polymerization-induced molecular self-assembling process. This process was observed in-situ by time-resolved small-angle neutron scattering (SANS) experiment. The SANS profiles measured exhibited three time regions, where (i) the selective growth of PI chains occurs; (ii) the living chain ends switch from isoprenyllithium to styryllithium, and (iii) the SANS exhibited the polymerization induced disorder-to-order transition and order-to-order transition.

  • PDF

수용액 내 폴리스티렌-폴리에틸옥사이드 이중블록공중합체 미셀 구조에 대한 소각중성자산란 연구 (Small-Angle Neutron Scattering Study of the Structure of Micelles Formed by a Polystyrene-Poly(ethylene oxide) Diblock Copolymer in Aqueous Solution)

  • 강병욱;최미주;황규희;이광희;진병석
    • 폴리머
    • /
    • 제33권5호
    • /
    • pp.485-489
    • /
    • 2009
  • 중수소화 폴리스티렌-폴리에틸렌옥사이드 이중블록공중합체(dPS-PEO)로 형성된 미셀의 구조에 대한 온도 의존성을 소각중성자산란(SANS)을 이용하여 조사하였다. SANS 데이터는 코어-쉘 모델의 form factor와 hard-sphere structure factor를 결합하여 분석하였으며, 산란 곡선 맞춤을 이용하여 미셀 응집수와 코로나 반경을 구하였다. 온도가 $25^{\circ}C$에서 $45^{\circ}C$로 증가함에 따라서 미셀 응집수는 229에서 240으로 변화하였으며, 이로 인해 코어 반경이 증가하였다. 그러나, 미셀의 쉘 두께는 6.2 nm에서 5.8 nm로 감소하였다. 이러한 구조적 변화는 온도 증가에 따라서 PEO 블록의 소수성이 증가함으로써 코로나 내의 친수성 그룹 당 수화 부피가 감소하였기 때문이다.

반사회적 의식이 반영된 시대복식의 특성에 관한 연구 - 18세기 상-뀔로뜨와 1960, 70년대 히피 스타일의 비교를 중심으로 - (A Study of Dress Characteristics with Respect to Anti-Social Resisting Consciousness - Focus on the Relationship between 18th Century Sans-Culotte and a Hippy Style During the 1960s and 1970s as a Comparative Perspective -)

  • 전여선;김영삼
    • 복식
    • /
    • 제62권6호
    • /
    • pp.112-126
    • /
    • 2012
  • The style of a dress allows important characterization of an era since they reflect contemporary politics, society, culture and arts. Within a same category, period costumes develop into styles that reflect specific consciousness. The research method and the scope of the study are as follows: the research adopts a historical study method and a comparative research from a microscopic point. The scope includes resistance costumes that proceed with sans-culotte that comprises of the resistance party during the 18th French Revolution (1783-1799), and also a Hippy style which was popularized during the 1960s and 1970s for its anti-war movement. We researched both similarities and differences of design factors reflecting resisting consciousness in costumes that affected costume characteristics related to their socio-cultural background. Sans-culotte and the Hippie style reflect a common denominator in anti-social resisting customs. First, they show common characteristics that combine fashion trends of resistant element and design features. Second, they have common features which are the characteristics of deviation. On the other hand, these two customs also present a discriminative denominator in anti-social resisting customs. In the case of sans-culotte, they tend to symbolize confrontation by dividing into two equal parts: the old and new mode. Sans-culotte confronts the conventional mode and promotes practical costume styles based on justice standpoints. First, hippies pursue an exposition of individual emotions that disclose internal meanings of love and desire. Second, they focus on subjective characteristics and chase after masteries and pleasures by expressing intensity. Third, it extends and develops folk costumes from many countries that reveal ethnic trends. Therefore, this research compares and contrasts different changes in the fashions of revolutionary periods, and aims to recognize the relationship between design and costume characteristics, thus contributing to the predictions of future changes in fashion.

정신분열병 환자에서 갑상선기능과 기분증상 및 신체증상 (Thyroid Dysfunctions Associated with the Mood Symptoms and the Psychosomatic Symptoms in Patients with Schizophrenia)

  • 김세희;한덕현;나철;민경준;주소연
    • 정신신체의학
    • /
    • 제17권1호
    • /
    • pp.30-36
    • /
    • 2009
  • 연구목적 : 갑상선기능은 기분, 인지기능, 불안, 수면 등의 증상과 관련된다. 갑상선기능이상 시에 정신분열병 환자에서 음성증상, 기분, 신체증상에 어떤 차이가 있는지, 또 각각의 증상 변화와 어떻게 연관되는지를 연구하였다. 방법 : 정신분열병으로 입원했던 환자 65명을 입원 당시의 갑상선호르몬 수치에 따라 갑상선기능불안정 군과 갑상선기능정상 군으로 나누었다. 두 군의 입원 당시와 8주 후에 평가했던 음성증상평가척도(Scale for the Assessment of Negative Symptoms ; 이하 SANS), 양성증상평가척도(Scale for the for the Assessment of Positive Symptoms ; 이하 SAPS), 벡우울증척도(Beck Depression Inventory ; 이하 BDI), 신체감각증폭척도(Somatosensory Amplication Scale ; 이하 SSAS)의 변화를 비교하였다. 각 환자들은 항정신병약물 치료를 포함한 입원 치료를 받았으며, 갑상선기능이 불안정했던 경우 4주 후에 갑상선호르몬의 정상화를 확인하였다. 결과 : 8주 뒤에 갑상선기능정상 군과 갑상선기능불안정 군에서 SANS, BDI, SSAS 변화 차이가 의미 있게 나타났다. 갑상선기능정상 군에서 갑상선기능불안정 군에 비해 척도 점수가 크게 낮아졌는데, SANS는 23.3%(F=57.0, p<0.01), BDI는 19.6%(F=12.9, p<0.01), 신체감각증폭척도는 16.2%(F=17.1, p<0.01) 더 변화가 컸다. SANS, BDI, SSAS 세 지표 간에 유의한 상관관계는 없었다. 결론 : 정신분열병 환자들에게서 갑상선기능이 음성증상, 우울감, 신체증상에 관련된 예후에 표지가 될 수 있을 것이다.

  • PDF

들뢰즈의 기관 없는 신체론에 기반한 현대 패션일러스트레이션의 신체특성 (Body Modification in Fashion Illustrations Based on the Theory of 'Corps sans Organes' of Deleuze)

  • 이지현
    • 복식
    • /
    • 제61권9호
    • /
    • pp.27-38
    • /
    • 2011
  • This study focused on the body modification in fashion illustration based on 'Corps sans Organes' of Deleuze. An argument about the changes of ideal body to define the aesthetic consciousness of times has lasted for a long time. Therefore, analyzing body modification in fashion illustration to express the ideal beauty could be effective motives to understand the changes of ideal bodies related with socio-cultural meanings, and be helpful to understand the overall trends of modern fashion illustration. To classify the types of body modification, the concept of 'Corps sans Organes' of Deleuze was used as an analyzing tool. As the final result, the characteristics of body modification could be divided into three groups; the fragmentation of bodies, the pastiche of bodies, and the abstraction of bodies. First, in the fragmentation of bodies, which is related with flexibility, pluralism, and subjective views on body, the bodies were separated as molecules. Second, the elements of pastiche of bodies could be subdivided into five sub-groups; sex, plants, animals, texts and figure, and machines. The pastiche of bodies was used to extend the limitation of human capabilities and to reinterpret the human identities. Last, the abstraction of bodies based on contingency, indeterminacy, and subjective associations could be related with the nomadic and indefinite body images. The body modification could be considered as the context of nomadism, indeterminacy, and virtuality of modern-times, and it would be the basic data to understand the body modification in fashion illustrations.

Quantitative Analysis of ″Polymer-Balls″ in Aqueous Solutions by Small-Angle Neutron Scattering

  • Shibayama, Mitsuhiro;Okabe, Satoshi;Nagao, Michihiro;Sugihara, Shinji;Aoshima, Sadahito;Harada, Tamotsu;Matsuoka, Hideki
    • Macromolecular Research
    • /
    • 제10권6호
    • /
    • pp.311-317
    • /
    • 2002
  • The quantitative analysis of polymer micelles consisting of amphiphilic block copolymers was carried out by small-angle neutron scattering (SANS). The block copolymers, made of poly(2-ethoxyethyl vinyl ether-b-2-hydroxyethyl vinyl ether)(poly(EOVE-b-HOVE)), exhibited a sharp morphological transition from a homogeneous solution to a micelle structure with increasing temperature. This transition is accompanied by a formation of spherical domains of poly(EOVE) with a radius around 200 $\AA$. The variations of the size and its distribution of the domains were investigated as a function of polymer concentration and temperature. The validity of SANS analysis, including the wavelength- and incident-beam-smearing effects of the SANS instrument, was examined with a pre-calibrated polystyrene latex.

Sizes and Structures of Micelles of Cationic Octadecyl Trimethyl Ammonium Chloride and Anionic Ammonium Dodecyl Sulfate Surfactants in Aqueous Solutions

  • Kim, Hong-Un;Lim, Kyung-Hee
    • Bulletin of the Korean Chemical Society
    • /
    • 제25권3호
    • /
    • pp.382-388
    • /
    • 2004
  • The sizes and structures of micelles formed in aqueous solutions of cationic octadecyl trimethyl ammonium chloride (OTAC) and anionic ammonium dodecyl sulfate (ADS) surfactants were investigated using smallangle neutron scattering (SANS), self-diffusion coefficients by pulsed-gradient spin-echo (PGSE) NMR, and dynamic light scattering (DLS) methods. SANS and DLS data indicate that their structures are spherical at concentrations as high as 300 mM. As the total surfactant concentration increases, the peaks of SANS spectra shift to higher scattering vector and become sharper, indicating that the intermicellar distance decreases and its distribution becomes narrower. This is due to more compact packing of surfactant molecules at high concentrations. The intermicellar distance of around 100 ${\AA}$ above 200 mM corresponds approximately to the diameter of one micelle. The sizes of spherical micelles are 61 ${\AA}$ and 41 ${\AA}$ for 9 mM OTAC and 10 mM ADS, respectively. Also the self-diffusion coefficients by PGSE-NMR yield the apparent sizes 96 ${\AA}$ and 31 ${\AA}$ for micelles of 1 mM OTAC and 10 mM ADS, respectively. For ADS solutions of high concentrations (100-300 mM), DLS data show that the micelle size remains constant at $25{\pm}2{\AA}$. This indicates that the transition in micellar shape does not take place up to 300 mM, which is consistent with the SANS results.

Optical Font Recognition For Printed Korean Characters Using Serif Pattern of Strokes

  • Kim, Soo-Hyung;Kim, Sam-Soo;Kwag, Hee-Kue;Lee, Guee-Sang
    • 대한전자공학회:학술대회논문집
    • /
    • 대한전자공학회 2002년도 ITC-CSCC -2
    • /
    • pp.916-919
    • /
    • 2002
  • This paper introduces the problem of typeface classification of Hangul characters and proposes features for typeface classification among Serif and Sans-serif classes. Serif classes have a small decorative stroke around the beginning of vertical strokes, while Sans-serif classes have no serif. Therefore, the serif part is first segmented from the vertical strokes, and the direction of the serif is computed as the feature for Hangul typeface identification. To evaluate the performance of the proposed system, we used 3,000 characters extracted from Korean documents - 1,500 from Serif fonts, other 1,500 from Sans-serif fonts.

  • PDF

소각 중성자 산란(SANS)을 이용한 블록 공중합체 마이셀의 동역학 연구 (SANS Study on Dynamics of Block Copolymer Micelles)

  • 최수형
    • 한국고분자학회지:고분자과학과기술
    • /
    • 제24권6호
    • /
    • pp.585-589
    • /
    • 2013
  • 고분자 시스템에서 동역학은 열역학적 평형상태에 도달하는 메카니즘을 밝히는 중요한 분야이다. 용융 고분자에 비해 상대적으로 블록 공중합체 마이셀에 대한 동역학 연구는 실험적 한계와 이론적 배경의 부재로 인해 충분한 연구가 이루어지지 못하였다. 하지만, 최근 TR-SANS를 이용하여 고분자 마이셀의 동역학 연구가 점차 증가하고 있는 추세이다. 마이셀 동역학과 관련하여 현재까지 이루어진 연구 결과도 충분히 중요한 통찰력을 제시해주고 있지만, 아직 개척되지 못한 부분이 많이 남아있는 것도 사실이다. TR-SANS의 개념은 고분자 마이셀 뿐만 아니라 다양한 고분자 시스템에 적용할 수 있고, 더 나아가 Neutron Reflectivity에 적용할 경우 박막 내에서 고분자의 동역학도 연구할 수 있을 것으로 기대된다. 또한, TR-SANS 개념은 고분자 동역학 연구 분야 외에도 의학/생명공학 등 넓은 분야에서 이용될 수 있을 것으로 기대된다.

  • PDF