• Title/Summary/Keyword: 자발적 형성

Search Result 139, Processing Time 0.027 seconds

Dynamic Behavior Study Using Videomicroscopy in Systems Containing Polar Oils and Nonionic Surfactant (극성 오일, 비이온성 계면활성제를 포함한 계에서의 Videomicroscopy를 이용한 동적 거동에 관한 연구)

  • Lim, Jong-Choo
    • Applied Chemistry for Engineering
    • /
    • v.8 no.3
    • /
    • pp.473-481
    • /
    • 1997
  • Enhanced videomicroscopy was used to observe the dynamic behavior which occurred when water containing pure nonionic surfactant was carefully contacted with equal volumes of polar oils such as oleyl alcohol and oleic acid at various temperatures. A key component of the system is a vertical-stage microscope which provides for stable interfaces by locating the oil above the denser aqueous phase. This arrangement allowed intermediate phases formed at the surface of contact to be clearly observed, as well as any spontaneous emulsification which developed. Contacting experiments with $C_{12}E_5$ as the surfactant and with pure oleyl alcohol and oleic acid soils showed little activity below the cloud point but vigorous activity at higher temperatures including formation of an intermediate lamellar liquid crystalline phase. Diffusion path theory, which allows prediction of spontaneous emulsification resulting from diffusion and of intermediate phase formation during contacting processes, was used to understand the dynamic behavior seen during contacting experiments. Tentative diffusion paths for the contacting experiments with pure oleyl alcohol were presented with the aid of a partial phase diagram of the oleyl alcohol-water-$C_{12}E_5$ system.

  • PDF

Exploring Middle School Students' Learning Development through Science Magazine Project with Focus on the Perspective of Participation (과학 잡지 프로젝트를 통한 중학생의 학습 변화 탐색: 참여의 관점을 중심으로)

  • Lee, Min-Joo;Kim, Heui-Baik
    • Journal of The Korean Association For Science Education
    • /
    • v.31 no.2
    • /
    • pp.256-270
    • /
    • 2011
  • This study was designed to explore how learners' participation develop if provided with opportunities for various scientific practices and experiences in writing science magazine articles as an extra-curricular club activity and what factors facilitate these participation development. Data from participant observations, in-depth interviews with students, and documents were used to extract the common characteristics of the practices. The learners' development was categorized into 3 stages in terms of participation in the community of practice: peripheral participation, transitional participation, and full participation. As participation develops, situational interest developed to individual interests and value attachment. Students sought to get ideas from every day life, and finally, in the stage of full participation, advances in writing showed the characteristics of knowledge transformation. Best of all, the participants enjoyed and valued their participation showing identities as journalists. The nature of science magazine article, external scaffolding, and internalization through enjoyment and value attachment appeared to be decisive factors that facilitate the development of participation. Student's enculturation of writing for learning offers a possibility that continue to do so, even after they have left formal schooling and make a basis for lifelong learning.

The Inclusion Complex Formation of Cyclodextrin and Congo Red in Aqueous Solution (수용액상에서 Cyclodextrin과 Congo Red 간의 복합체 형성)

  • Kim, Chang Suk;Kim, Dong Won;Bahn, Woo Kyoung
    • Analytical Science and Technology
    • /
    • v.15 no.2
    • /
    • pp.115-119
    • /
    • 2002
  • The formation of inclusion complexes between cyclodextrin(CD) and Congo red was studied by spectrophotometric methods at various temperatures. The cavity sizes are 0.49 nm, 0.62 nm for $\alpha$-and $\beta$-CD, respectively. Therefore, $\alpha$-CD was not found to form an inclusion complex with Congo red due to steric hinderance. In the $\beta$-CD use two $\beta$-CD molecules formed an inclusion complex with one molecule of Congo red, from the slope of the S-shaped curve increased. Two prominent isosbestic points appear at 346 nm and 478 nm. The formation constants were decreased with the increasing temperatures, due to low binding energy between $\beta$-CD and Congo red. The thermodynamic parameters were calculated from the plot of $lnK_f$ vs 1/T. The $\Delta$H, $\Delta$S and $\Delta$G were -50.73 kJ/mol, $-108.96J/K{\cdot}mol$ and -18.26 kJ/mol, respectively.

Determination of inclusion complex formation constants for the β-CD and [Cu(Dien)(sub-Py)]2+ ion by the spectrophotometric methods (분광 광도법에 의한 β-CD와 [Cu(Dien)(sub-Py)]2+이온간의 복합체 형성 상수 결정)

  • Kim, Chang Suk;Oh, Ju Young
    • Analytical Science and Technology
    • /
    • v.20 no.5
    • /
    • pp.406-412
    • /
    • 2007
  • The formation of inclusion complexes between ${\beta}$-cyclodextrin and diethylenetriamine substituted-pyridine copper(II) perchlorate; [Cu(dien)(sub-py)] $(ClO_4)_2$, were studied by spectrophotometric methods. On account of charge-transfer band(MLCT) and $^2T_2{\rightarrow}^2E$, the two high peaks were observed as an inclusion complex for the [${\beta}$-CD]$[Cu(dien)(p-Cl-py)]^{2+}$ in the ultraviolet region of the spectrum. The ${\beta}$-CD and $[Cu(dien)(sub-py)]^{2+}$ ion formed a 1:1 complex, and the formation constants were decreased with the increasing temperatures, due to weak binding energy between ${\beta}$-CD and $[Cu(dien)(sub-py)]^{2+}$ ion. This reaction was controlled by enthalpy. In a correlation of the Hammett substituent constants and formation constants for the reaction, formation constants were increased by strong binding energy in the inclusion complexes when electron donating groups were substituted in pyridine ring.

The Effect of Wedding Industry Employees Exchange Relationship on their Job Satisfaction and Voluntary Service Intentions (웨딩산업종사자의 교환관계가 직무만족과 자발적 서비스 의도에 미치는 영향에 관한 연구)

  • Byun, Sang-Woo;Lee, Hyang-Sook
    • Management & Information Systems Review
    • /
    • v.32 no.5
    • /
    • pp.69-88
    • /
    • 2013
  • This study aimed to analyze the effects that the exchange relationship among employees engaged in the wedding industry in Busan, Ulsan and Gyeongnam area exerted on job satisfaction and voluntary service intentions. For this purpose, a theoretical model was presented based on previous studies and the relationship among variables was analyzed based on the analysis results through a survey. There have recently been great difficulties in the whole wedding industry due to the global economic depression and the low birthrate. Moreover, it is hard to optimize the future business environment. In particular, the low birthrate has weakened the demand base of the wedding industry. As a result, it is expected that the competition among companies will be more fierce in the wedding industry. Employees' voluntary service intention become much more important to overcome difficulties in this industry. Employees' voluntary service intentions can be possible when their job satisfaction is achieved. Many studies report the result that this job satisfaction can naturally be achieved when the high quality exchange relationship among a leader, team members (co-workers) and customers is formed. It is viewed that employees' voluntary service intentions should be induced through job satisfaction to improve the profitability through the efficient operation and management of the system. A leader of the organization should make an effort to form the high-quality exchange relationship with members, support so that team members(coworkers) and other employees can get along together and the teamwork can be improved and induce them to improve a high level of service quality with friendly customer services. In spite of the significance of the study discussed above, there are the following limitations in this study. There is a limit to a certain extent in generalizing study conclusions because the study was limited to the Busan, Ulsan and Gyeongnam area. If practical surveys which full- and part-time employees are included in the composition of samples are conducted for wedding suppliers in the country in the future, the quality of study will be able to improve.

  • PDF

A Study on the Formation of Leader-Member's Interpersonal Trust Relationship and Member's Task Behavior (상사-부하간의 대인적 신뢰관계의 형성과 영향에 관한 연구)

  • 손기영
    • Journal of the Korea Society of Computer and Information
    • /
    • v.4 no.1
    • /
    • pp.92-98
    • /
    • 1999
  • Interpersonal trust is the mutual "faithfulness" on which all social relationship ultimately depend and applicable to the relations among people rather than to their psychological states taken individually. Recent development in the organizational sciences reflect the importance of interpersonal trust relationships for sustaining individual and organizational effectiveness, researchers have recongnized trust's influence on coordination and control at both institutional and interpersonal levels of organization. Because economic action is embeded within networks of social relationships. researchers have argued that efficiency within complex systems of coordinated action is only possible when interdependent actors work together effectively. Thus, for managers and professionals in organizations, developing and maintaining trust relationship is especially import. The purpose of the present study is to investigate the mechanism of interpersonal trust in the organization. Especially, the major concern of this study is to verify role of interpersonal trust in the member's task behaviork behavior

  • PDF

Resistance to Cisplatin Renders High Metastatic Potential in Human Non-Small Cell Lung Cancer Cell Line (Cisplatin 내성을 보이는 비소세포폐암 세포주에서의 전이 능력 증가)

  • 차대원;김진국;손동섭;조대윤;양기민
    • Journal of Chest Surgery
    • /
    • v.34 no.5
    • /
    • pp.377-385
    • /
    • 2001
  • 배경: Cisplain과 같은 세포돗성 약제에 대한 내성은 폐암 치료 실패의 중요한 원인이다. 이러한 항암제에 대한 내성의 발생기전은 복잡하고 아직 완전히 알려져 있지 않지만 불량한 예후의 원인으로 생각된다. 특히 약제 내성이 발생한 환자의 경우 기존의 종양의 급속한 성장뿐 아니라 새로운 전이 병소가 급속히 발생 및 진단됨은 약제 내성을 가진 종양이 전이에의 용이성을 획득하는게 아닌가 의심케한다. 이를 규명하기 위해 Cisplatin에 내성을 지닌 비소세포폐암 세포주 H460/CISm이 전이 능력을 Cisplatin에 민감한 비소세포폐암 세로주 H460과 비교하고자 한다. 대상 및 방법: 약제 내성 세포주를 확보하기 위하여 H460세포에 cisplatin을 점차적으로 증가시켜 처리한 후 배양하였다. H460 세포와 H460/CIS 세로에서의 혈관신생인자와 성장관련인 자의 발현양상, gelatin zymography 분석 그리고 in vivo 실험으로 nude 마우스에서의 자발적 전이 능력의 차이를 비교하였다. 결과: H460 세포를 이식한 마우스에 폐에서는 종양이 형성되지 않았으나 H460/CIS세포를 이식한 마우스 10마리중 8마리에서 종양이 형성되었다. 또한 H460/CIS 세포주에서 전이 관련 유전자로 알려진 angiopoietin-1, vascular endothelial growth factor, basic fibroblast growth factor, matrix metalloproteinase 2 등이 더 발현되었고, 전이의 침습성을 유발하는 gelatinase의 활성이 증가된 것을 확인할 수 있었다. 결론: 본 여구 결과를 통해 cisplatin에 내성을 가진 비소세포폐암세포에서 전이 능력이 증가될 수 있다고 여겨지며 이러한 사실을 토대로 초기 비소세포폐암 환자의 수술 전 항암약물요법의 타당성에 대해서 이야기 하기 위해서는 많은 임상적 연구가 필요하리라 생각된다.

  • PDF

Design-Art: Focusing on the Concept-Forming Process of Design-Art (디자인아트: 개념 형성 과정을 중심으로)

  • Kang, Hyun-Dae;Kim, So-Hyun
    • The Journal of the Korea Contents Association
    • /
    • v.12 no.8
    • /
    • pp.178-186
    • /
    • 2012
  • This study examined the concept-forming process of Design-Art and based on it, drew the significance of Design-Art. Design-Art is generated by the policy cultivating star artists and star designers so as to pioneer new art-market in 1990s in the foundation of anti-area formed by Postmodernism in 1960s. It started to be vitalized while designers were born as author. At the same time, because of the information's popularity by internet's propagation, users started to manufacture and propagate contents volunteerly. Meanwhile, designers accepted artistic value so as to guarantee independent position, so the area of Design-Art became more strengthened. Therefore, Design-Art means 'design as an art' and Design-Artist obtained general meaning, 'designer as an author'. In 2000s, it secured variety because of the acceptance of existing art galleries' Design-Art works and forming of new Design-Art market such as Design-Art fair, and vitalization of the market played its own roles with the movement to create new-concept of design in design ecology. Based on the contents, this paper analyzed Design-Art works by Design-Artists working actively in actual field and examined the possibility of future development of Design-Art.

Fabrication of Nanodot Arrays Via Pulsed Laser Deposition Technique Using (PS-b-PMMA) Diblock Copolymer and Anodic Aluminum Oxide Templates (고분자 공중합체와 알루미늄 양극 산화막 템플레이트를 이용한 나노점 배열 형성)

  • Park Sung-Chan;Bae Chang-Hyun;Park Seung-Min;Ha Joeng-Sook
    • Journal of the Korean Vacuum Society
    • /
    • v.15 no.4
    • /
    • pp.427-433
    • /
    • 2006
  • We have fabricated nanodot arrays by using phase separated (PS- b- PMMA) diblock copolymer film and anodic aluminum oxide (AAO) membrane as templates with hexagonal arrays of cylindrical microdomains perpendicular to the substrate. Pulsed laser deposition technique was used to deposit various kinds of materials including Ag, Ni, ZnO, Si:Er, and Co/Pt onto Si substrates. The size and separation of nanodots correspond to those of the templates used, The density of nanodots was estimated to be $6{\times}10^{11}/cm^2$ and $1{\times}10^{10}/cm^2$ when the diblock copolymer and AAO were used, respectively. In particular, the optical properties of ZnO and Si: Er nanodot arrays were investigated and the strong photoluminescence at 380 nm and $1.54{\mu}m$ was observed from ZnO and Si:Er nanodot arrays, respectively.

Restoration of Local Community Based on Apartment Residential Space (아파트 주거공간에 기초한 지역공동체 형성에 관한 연구)

  • Yim, Seok-Hoi;Lee, Chul-Woo;Jeon, Hyeong-Soo
    • Journal of the Korean association of regional geographers
    • /
    • v.9 no.3
    • /
    • pp.314-328
    • /
    • 2003
  • This study aims at exploring the restoration of local community based on apartment residential space through the questionnaire survey of residents and community movement organizers. Apartment residential space has a serious limit to the restoration of local community due to the physical feature of closing compartment. But, at the same time, it has many communal elements as well. The survey shows that residential community movements are developing beyond compensatory community movement, although it is yet to be an ideal type of local community in a nonnative sense. Generally, apartment women's associations, together with the representative commission of residents, play a key role in residential community movements. Particularly, community movement activities have a positive effect on improving the neighborhood relationship. Residents themselves think so as well. This study implies the value and possibility of apartment residential movement as an alternative strategy against contemporary urban problems.

  • PDF