• Title/Summary/Keyword: self -assembly

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Preparation of Hydrated Liquid Crystalline Vesicle Using Mutual Self-Association between Ceramide and Phospholipid (인지질/세라마이드 혼합물의 상호적 자가회합 특성을 활용한 수화 액정형 베시클 제조)

  • Park, Min Seon;Choi, Jeong Won;Lee, Seol-Hoon;Jin, Byung Suk
    • Applied Chemistry for Engineering
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    • v.31 no.5
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    • pp.545-551
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    • 2020
  • An attempt was made to prepare hydrated liquid crystalline vesicles by utilizing a mutual self-assembly between phospholipid and ceramide. When an edge activator was added to the mixture of phospholipid and ceramide, it was possible to prepare a vesicle containing a high content of poorly soluble ceramide. In this study, we investigated changes in structural and thermal behaviors of the hydrated liquid crystalline phase according to the mixed composition between phospholipid, ceramide, and sodium deoxycholate. Also, both the droplet size of the vesicles with different composition and stability of the vesicle dispersion solution were observed. From results of the experiments, by increasing the ratio of ceramide up to 70% in the mixture between phospholipid and ceramide, a formulation containing 3.5 wt% of ceramide in the vesicle dispersion solution could be obtained.

Fabrication of Hollow Micro-particles with Nonspherical Shapes by Surface Sol-gel Reaction (표면 솔-젤 반응을 활용한 마이크로미터 크기의 비구형상 공동 입자의 제조)

  • Cho, Young-Sang;Jeon, Seog-Jin;Yi, Gi-Ra
    • Korean Chemical Engineering Research
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    • v.45 no.6
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    • pp.611-618
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    • 2007
  • We demonstrate the sol-gel coating technique of colloidal clusters for producing hollow micro-particles with complex morphologies. Cross-linked amidine polystyrene (PS) microspheres were synthesized by emulsifier-free emulsion copolymerization of styrene and divinylbenzene. The amidine PS particles were self-organized inside toluene-in-water emulsion droplets to produce large quantities of colloidally stable clusters. These clusters were coated with thin silica shell by sol-gel reaction of tetraethylorthosilicate (TEOS) and ammonia, and the organic polystyrene cores were removed by calcination at high temperature to generate nonspherical hollow micro-particles with complex morphologies. This process can be used to prepare hollow particles with shapes such as doublets, tetrahedra, icosahedra, and others.

Self-assembly of ZnO Stripes Prepared by Anodization in an Ethanolic Sulfuric Acid (에탄올/황산 혼압액에서 양극산화법을 이용한 자기정렬된 ZnO 줄무늬 구조 제조 연구)

  • Kim, Sung Joong;Choi, Jinsub
    • Korean Chemical Engineering Research
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    • v.46 no.4
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    • pp.686-691
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    • 2008
  • There are no many research reports on the preparation of ZnO by electrochemical oxidation since the zinc oxide is very easily dissolved in an acidic or basic environment, even though zinc oxides have attracted many attentions because of their optical/electrical properties. In this paper, we describe the fabrication of self-ordered stripes of ZnO by anodization of Zn in an ethanolic sulfuric acid. The formation of stripes of ZnO originating from Zn is attributed to water-selective dissolution of ZnO during anodization. We study in detail the effects of concentration of $H_2SO_4$, applied potential, anodization time, and addition of a small amount of water on the fabrication of stripes of ZnO. Mechanisms for the fabrication of ZnO stripes are discussed in terms of the above-mentioned effects.

Fabrication and (Photo)Electrochemical Properties of Fe2O3/Na2Ti6O13/FTO Films for Water Splitting Process (물분해용 Fe2O3/Na2Ti6O13/FTO 박막 제조 및 특성평가)

  • Yun, Kang-Seop;Ku, Hye-Kyung;Kang, Woo-Seung;Kim, Sun-Jae
    • Corrosion Science and Technology
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    • v.11 no.2
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    • pp.65-69
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    • 2012
  • One dimensional(1D) $Na_2Ti_6O_{13}$ nanorods with 70 nm in diameter was synthesized by a molten salt method. Using the synthesized nanorods, about 750 nm thick $Na_2Ti_6O_{13}$ film was coated on Fluorine-doped tin oxide(FTO) glasss substrate by the Layer-by-layer self-assembly(LBL-SA) method in which a repetitive self-assembling of ions containing an opposite electric charge in an aqueous solution was utilized. Using the Kubelka-Munk function, the band gap energy of the 1D-$Na_2Ti_6O_{13}$ nanorods was nalyzed to be 3.5 eV. On the other hand, the band gap energy of the $Na_2Ti_6O_{13}$ film coated on FTO was found to be a reduced value of 2.9 eV, resulting from the nano-scale and high porosity of the film processed by LBL-SA method, which was favorable for the photo absorption capability. A significant improvement of photocurrent and onset voltage was observed with the $Na_2Ti_6O_{13}$ film incorporated into the conventional $Fe_2O_3$ photoelectrode: the photocurrent increased from 0.25 to 0.82 mA/$cm^2$, the onset voltage decreased from 0.95 to 0.78 V.

Research Trends Review of Undergraduates' on Entrepreneurship Education Program to Develop the Entrepreneurship Program for Nursing College Students (간호대학생 창업교육프로그램 개발을 위한 대학생 대상 창업교육프로그램 연구 동향 고찰)

  • Noh, Wonjung;Kang, Jiwon;Lee, Youngjin
    • Journal of Convergence for Information Technology
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    • v.9 no.2
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    • pp.148-154
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    • 2019
  • The study was performed to prepare basic data for the development of entrepreneur education programs for nursing students through literature review and text network of relevant studies on entrepreneurship education for college students. The research was found in the database of the Korea Education and Research Information Service, the Korean Academic Information Service System, DBpia and the National Assembly Library with keywords such as 'entrepreneur', 'student', 'education', 'program' and 'training. The final selected paper was 35 studies in Korea from 2000 to September 2016. The largest number of studies have been conducted since 2011 with 85.71%, and the largest proportion of survey(88.57 %). The major independent variables were entrepreneur self-efficacy and entrepreneurship and the dependent variables were entrepreneur intention and entreprenuer self-efficacy. Based on this result, entrepreneur education programs will be developed suitable for the target, and it can promote the entrepreneur education for nursing students.

A Systematic Review of the Variables Related to Post-Traumatic Stress Disorder in Firefighters (소방공무원의 외상 후 스트레스 장애 관련변인에 관한 체계적 문헌고찰)

  • Kang, Min-Ju;Kim, Young-Hwa;Han, Seung-Woo
    • Fire Science and Engineering
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    • v.33 no.2
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    • pp.164-172
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    • 2019
  • This study examined the Post-Traumatic Stress Disorder (PTSD)-related variables of firefighters through a systematic literature review. Electronic databases were searched, including RISS, National Assembly Library, NDSL, KmBase. The search terms were PTSD, Post-Traumatic Stress, Post-Traumatic Stress Disorder and Firefighter. Eleven studies from 146 references screened were included. All studies were non-experimental and correlational analyses. The positive correlation factors were age, duration of work, traumatic events, frequency of mobilization, number and strength of traumatic events experienced, work burden, coping method, D-type personality, depression, and anger rumination. The negative correlation factors were resilience, social support, self-esteem. To improve the mental health of firefighters in the future, professional intervention programs should be constructed to improve resilience, social support, and self-esteem, which are protective factors of PTSD.

A Study on the Reality and Improvement of Autonomous Police System in Jeju Special Self-Government Province (제주자치경찰 시스템의 실태와 발전모델에 관한 연구)

  • Cho, Chul-Ok
    • Korean Security Journal
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    • no.14
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    • pp.485-516
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    • 2007
  • Jeju Special Self-Government Province adopted an autonomous police system for the first time since 60 years in Korean police. The purpose of autonomous police system is to offer a police service to be suitable in regional conditions. But Jeju autonomous police system for nearly one year after adoption is criticized to be established on the ground of political reason but not local decentralization. Actually Jeju autonomous police has not a clear cut jurisdiction and operation scope because of the jurisdiction duplication between national and autonomous police. The original task is confined on environment and sightseeing so on given to administration police for local self-government. So criminal investigation authority on general crimes is not to Jeuju autonomous police on account of special judicial police. First, it is the structural rationalization of Jeju autonomous police system. It speaks that Jeju provincial police bureau and police station have to be as national police institution, on the other hand, patrol district station and police box have to be as autonomous police institution. Of course, functional division has to be followed. National police performs managing all the assembly and demonstration by the management law on assembly and demonstration including the suppression against any large scale demonstration and disturbance, also the investigation on serious crimes just as international crimes and broaden area crimes including all the felony. Together national police performs the duty concerned to all the foreign affairs and national securities in along with the investigation on traffic accidents. On the other hand, autonomous police performs the function for citizen's life safety as crime prevention and the enforcement on the violation against police operation law, together the traffic management and the regulation on traffic violations. and the investigation on minor crime as simple violence or petty larceny including the management on local big events. Second, the budgetary of autonomous police is rationalized by the share of budgeting between Korean government and Jeju special self-government province. Third, urgent arrest authority on general crime and the rights of claims for the summary trial on minor crimes are given to autonomous police. Of course, this problem is resolved naturally in case of giving the investigation rights to autonomous police on minor crimes.

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Under the Pressure of the Topic Selection and Representation Rules of the Mass Media over the Slow Political Process Time - For Example the Televised Debate to Elections to the Federal Assembly in Germany (미디어 생산시간이 미디어 정치에 미치는 영향에 관한 연구 - 독일총선의 TV토론을 중심으로)

  • Shim, Young-Sub
    • Korean journal of communication and information
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    • v.45
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    • pp.187-219
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    • 2009
  • Under the pressure of the selection of topics and the presentation rules of mass media, politics in media society increasingly resort to professionalized forms of theatrical staging as a means of self-portrayal. Although these staging methods are not contradictory to what is actually going on in politics, they strongly advantage the tendency to focus exclusively on the staging of an event. Through their competition for public attention, politicians have been developing sophistication regarding placement and staging of events as well as regarding factual information. In the process of this transformation, politics that are issue-related and based on binding decisions are being gradually transformed into symbolic politics. Moreover, through their appearance on TV, politicians first of all need to possess presentational skills which are not necessarily related to their political achievements. Still, presentational skills decide over the success in politics of those politicians. The reason is that a politician who possesses presentational skills is still being perceived as being successful even if his political achievements notedly lag behind. On the other hand, political achievements are being underrated if a politician lacks the talent to present himself in front of the media. “The staging of politics, “politainment”, on the stage of mass media is evolving into a key structure which is responsible for a new coinage of politics in all different kinds of dimensions: the selection of staff, the role of action programs and their impact for the legitimation of political acting, even in relation to therole of pivotal political institutions such as parties and parliaments in the political process. The TV debates during the Bundestag elections of the year 2002 and 2005 are being analyzed and judged as “staging of politics”(politainment). Self-dramatization in media society concerning media discourses about politics and political self-portrayal has become a basic principle of political communication. Self-dramatization is a vital challenge for adequate political communication and content-based orientation in our present media democracies.

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Effects of the Russia's Ukraine Invasion on the Korea National Security (러시아의 우크라이나침공이 한국안보에 미치는 영향)

  • Jong Wha Lim
    • Industry Promotion Research
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    • v.8 no.3
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    • pp.175-180
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    • 2023
  • On the day of 24 February 2022, Ukraine was invaded by Russia which signed to ensure definitely the Ukraine's national sovereignty, territorial integrity and security under the UN General Assembly Security Council A/49/765, named as the Budapest Agreement. This invasion is the 2nd invasion succeeded in Crimean Peninsula invasion of March 2014 after the Ukraine's national independence in 1991 from the USSR. However this invasion has been continuing for much more than one year. Although Ukraine President appealed the 'peace' toward Russia and claimed also to justify the Budapest Agreement of 1994 toward U.S.A., even any justifications were not appealed. The critical moment of the national abolition could be escaped from the unified desperate spirit of all nations including the president, political-social leaders and military members. Such patriotic and self-help spirits in Ukraine resulted in the active supports from the U.S.A., western and eastern free democratic countries, NATO and EU, and even the neutral countries. Furthermore these supports are increasing much more day-after-day. The lessons which the Ukraine War offers to the Korean national security should be cored with the development of self-reliant national defense capabilities, self-strenuous efforts and unity strengthening of the Korean-U.S. Alliance with the deep confidence.

Systematic Review of Korean Studies on Simulation within Nursing Education (시뮬레이션을 활용한 한국간호교육 연구에 대한 체계적 고찰)

  • Kim, Jung-Hee;Park, In-Hee;Shin, Sujin
    • The Journal of Korean Academic Society of Nursing Education
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    • v.19 no.3
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    • pp.307-319
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    • 2013
  • Purpose: The purpose of this study was to review nursing studies with regard to simulation- based learning in Korea. Methods: This systematic review examines the literature on simulation in nursing education from 2003 to 2012. The electronic databases reviewed included: RISS, the National Assembly Library, the National Library of Korea, and major nursing journal databases in Korea. The MeSH search terms included nursing, simulation, simulator, and standardized patient. Results: In total, 52 studies were included in the literature review. We included 21 quasi-experimental studies and 25 studies using high-fidelity simulation. They included knowledge and problem-solving ability in the cognitive domain; self efficacy, learning satisfaction, interpersonal relationships and communication, and confidence in the affective domain; and clinical performance ability and learning performance evaluation in the psychomotor domain. This systematic literature review revealed that simulation is useful in nursing education but uncovered a gap in the literature pertaining to the transfer of knowledge to performance and how to learn from cognitive reflection. Conclusions: This result suggests that it is necessary to conduct additional research on the cognitive learning process and transition to performance.