HPLC를 사용한 쌀 중 잔류농약 동시분석법

최재천,이영자,김소희,최수영,최희주,정성욱,박흥재,김우성 한국환경과학회 2005 한국환경과학회지 Vol.14 No.4

A simple and sensitive analytical method based on RP-HPLC with UV detector(225 nm) and mobile phases using 0.1% phosphoric acid and acetonitrile was developed for simultaneous determination of quinclorac, bentazone, 2,4-D, bensulfuron-methyl, dymuron, capropamide, pencycuron, ethofenprox. This method was resulted in recovery of 78~ 96% with RSD 3.3~7.5%. LODs 0.12~0.84 and LOQs 0.34~1.20 ㎎/L. Calibration curves were linear with r of 0.9995~ 0.9999.

이하선 임파절 전이를 동반한 상안검의 Merkel Cell Carcinoma 1례

김영호,최재영,이세영,최은창 대한이비인후과학회 1999 대한이비인후과학회지 두경부외과학 Vol.42 No.2

Nano-Electro-Mechanical Nonvolatile Memory (NEMory) Cell Design and Scaling

Choi, Woo Young,Osabe, Taro,King Liu, Tsu-Jae IEEE 2008 IEEE transactions on electron devices Vol.55 No.12

<P> The design and scalability of a nano-electro-mechanical memory (NEMory) cell are investigated via analytical modeling and finite element analysis (FEA) simulation. Proportionate scaling of all the cell dimensions provides for improved storage density together with low operating voltages and fast program/erase times. From FEA simulation, a 75-nm-long aluminum cantilever-beam NEMory cell is expected to have sub-1-ns erase and program times for sub-1-V operation. Because there are practical limits to beam and air-gap thickness scaling, it will be difficult to achieve low-voltage operation for very short beams <TEX Notation='TeX'><TEX>$(L_{\rm beam} ≪ \hbox{50}\ \hbox{nm})$</TEX></TEX>, unless a beam material with a low Young's modulus is used. Fracture strain imposes a fundamental limit for beam-length scaling. Thus, a high fracture-strain beam material is desirable to extend NEMory scalability. </P>

Nanogenerators: Fully Rollable Transparent Nanogenerators Based on Graphene Electrodes (Adv. Mater. 19/2010)

Choi, Dukhyun,Choi, Min-Yeol,Choi, Won Mook,Shin, Hyeon-Jin,Park, Hyun-Kyu,Seo, Ju-Seok,Park, Jongbong,Yoon, Seon-Mi,Chae, Seung Jin,Lee, Young Hee,Kim, Sang-Woo,Choi, Jae-Young,Lee, Sang Yoon,Kim, Jo WILEY-VCH Verlag 2010 ADVANCED MATERIALS Vol.22 No.19

<B>Graphic Abstract</B> <P>The cover shows an image of fully rollable transparent nanogenerators synthesized using chemical vapor deposition grown large-scale graphene sheets as transparent electrodes and piezoelectric ZnO nanorod arrays. Sang-Woo Kim, Jae-Young Choi, and co-workers report on p. 2187 the electrical and structural stability of the nanogenerators, with excellent charge scavenging performance under external mechanical loads such as bending and rolling. This study shows that graphene-based nanogenerators are very promising for self-powered rollable transparent device applications. <img src='wiley_img_2010/09359648-2010-22-19-ADMA201090066-content.gif' alt='wiley_img_2010/09359648-2010-22-19-ADMA201090066-content'> </P>

Floristic characteristics of vascular plants and first distributional report of Pseudostellaria baekdusanensis M. Kim in Yongneup wetland protected area

Young-Chul Kim,Hyun-Hee Chae,Sang-Heock Oh,Seung-Ho Choi2,Moon-Pyo Hong3,Gi-Heum Nam,Jae-Yoon Choi,Hyun-Sook Choi,Kyu-Song Lee 한국환경생태학회 2015 한국환경생태학회지 Vol.29 No.2

Yongneup wetland protected area, the only high moor in Korea, is a core area to conserve biodiversity. Even though the Yongneup wetland protected area is relatively small, various plant species are distributed in the Yongneup wetland protected area because it includes various habitats showing different environmental gradients. Vascular plants distributed in the Yongneup wetland protected area were identified as a total of 376 taxa that is composed of 73 families, 217 genera, 322 species, 3 subspecies, 44 varieties and 7 forms. For endangered plants designated by the Ministry of Environment, 5 species including Trientalis europaea var. arctica, Lilium dauricum, Halenia corniculata, Lychnis wilfordii and Menyanthes trifoliata were found and 34 taxa were confirmed to be distributed only in the mountainous wetland habitats. Regarding naturalized plants, a total of 11 taxa were distributed, but most of them were distributed in the areas where artificial interference has occurred. And in areas inside the wetlands that are relatively well preserved, 2 species of Bidens frondosa and Erigeron annuus were observed. In this study, the occurrence and distribution of Pseudostellaria baekdusanensis M. Kim, which was recently found in Mt. Baekdu and reported as a new species, were identified in the Yongneup wetland protected area. A wetland is a very vulnerable area to drastic environmental changes and damages to its ecosystem could cause the extinction of rare plant species which are distributed only in the wetlands. Therefore, it is mandatory that current status of the Yongneup wetland protected area is evaluated and actions to prevent rapid environmental changes are taken. Fourteen separate investigations were conducted in 2013 and another four in 2014, to evaluate current status of the Yongneup wetland protected area. These investigations have provided us the basic information for future actions of conservation and restoration.

한국 공영방송 지배구조의 정치적 독립성 연구 - 문재인 정부의 공영방송 개혁과제를 중심으로 -

최영재(Choi, Young Jae) 한국언론법학회 2020 언론과 법 Vol.19 No.3

이 연구는 한국의 방송제도의 중요한 숙원 과제의 하나인 공영방송의 정치적 독립성 제도 마련과 관련, 문재인 정부의 해결과제, 문정부의 공영방송 지배구조 개혁이 성공하지 못한 원인, 그리고 한국 공영방송의 법적 독립성(de jure independence) 확보 방안을 모색했다. 공영방송 독립성에 관한 이론 및 선행연구, 그리고 KBS, NHK, BBC의 지배구조 역사를 검토한 결과, 첫째 문재인 정부의 개혁 과제는 우선 경쟁적 정치상황에서 여야 합의로 마련된 공영방송 독립성 제도 개혁안의 실현으로 요약했다. 둘째 공영방송 인사와 규제에 대한 간섭 금지를 통한 정치적 후견주의 문제 해소이다. 셋째 이념과 정파성을 배제한 전문적인 공영방송 정책 수행을 통한 공영방송 전문직주의 문화 배양이다. 결국 문재인 정부는 공영방송 지배구조 개혁을 위한 절호의 정치적 계기를 살리지 못하고 임기중반까지 개혁성과를 내지 못했다. 이유는 후견주의 문제를 일으키는 집권세력 스스로의 문제를 개혁해 내지 못하고 대안적인 외부 개혁모형을 찾는데 시간을 소모했기 때문이다. 지금 상황에서 지속적인 공영방송 독립성 개혁을 위해서는 집권세력의 부당한 개입을 제어할 수 있는 정치 사회 시민세력과 공영방송 종사자들의 결집을 통한 자발적 공영방송 독립운동의 전개가 필요 할 것이다. 또한 불확실한 대안적 제도의 탐색 보다는 역사적으로 제도적 안정성이 입증된 BBC와 NHK의 주요 독립성 장치인 합의제 및 특별다수제에 의한 사장 임명, 공개 투명한 지배구조 구성 절차의 도입을 제안한다. This study examines the reasons for the unsuccessful reform of the Moon government"s public broadcasting governance structure, along with the Moon Jae-in administration"s task to establish a political independence system for public broadcasting, which is one of the important longing tasks of the Korean broadcasting system. It sought a way to secure de jure indepence of public broadcasting. As a result of reviewing the theory and prior research on independence of public broadcasting, and the history of governance structure of KBS, NHK, and BBC, the most priority reform task of the Moon Jae-in administration is the firstly realization of the reform proposal for the independence system of public broadcasting, prepared by the agreement of the opposition parties in a competitive political situation. Second, the problem of political clientelism is resolved by self-prohibiting interference with public broadcasting appointments and sanctions. Third, it is cultivating a culture of professionalism in public broadcasting through the implementation of professional public broadcasting policies excluding ideology and political factionalism. In the end, the Moon Jae-in administration failed to make use of the perfect political momentum for reforming the governance structure of public broadcasting and did not produce reform results until the mid-term. The reason is that the ruling powers themselves, causing the problem of clientelism, could not reform their own problems and spent time looking for an external alternative reform model. In the current situation, for the continued reform of the independence of public broadcasting, it will be necessary for the political and social civil forces and the public broadcasting workers to mobilize to control the unfair intervention of the ruling forces. It also proposes the introduction of a procedure for the establishment of an open and transparent governance structure, as well as the appointment of the president through a consensus system and a special majority voting system, which are the historically proven stable and main independence apparatus of the BBC and NHK.

시험성토 단면에서의 다짐에너지에 따른 LFWD 변형계수의 변화

최찬용(Choi Chan-Young),김현기(Kim Hyun-Ki),배재훈(Bae Jae-Hoon) 한국철도학회 2008 한국철도학회 학술발표대회논문집 Vol.- No.-

PLT where from site is used mainly with compaction maintenance of quality, CPLT and LFWD, in order to be a Young"s modulus of using a direct arrival wave executed a site experiment. According to the roller compaction number of times measured the degree which changes and a promise management aptitude evaluation executed.

미치광이풀 모상근 배양에서 Tropane Alkaloid 생산성 증진을 위한 최적 생물학적 엘리시터 선발

정희영,강승미,강영민,김용덕,양재경,정영관,최명석 Plant molecular biology and biotechnology research 2003 Plant molecular biology and biotechnology research Vol.2003 No.-

Scopolamine and hyoscyamine which belong to tropane alkaloids are the pharmaceutically valuable anticholinergic drugs. In order to increase the productivities, the effects of elicitation were investigated during hairy root cultures of Scopolia parviflora. Biotic elicitors originated from 3 fungi and 1 yeast were prepared as homogenate and supernatant and added to 3-week-old cultures. Both of homogenate and supernatant of Candida albicans elicitors increased the scopolamine production. The production of hyoscyamine was enhanced by homogenate of Fusarium solani and supematant of C. albicans. Most of the other fungal elicitors were also improved on the tropane alkaloid production compared to non-treatment. Among the elicitors tested, C. albicans was proved the optimal biotic elicitor on tropane alkaloids production. These results will be served mass production of tropane alkaloids by large-scale production.

상아질에 적용된 재 습윤제가 미세인장 결합강도에 미치는 영향

강희영,조영곤,김종욱,박병철,유상훈,진철희,최희영,기영재 大韓齒科保存學會 2004 Restorative Dentistry & Endodontics Vol.29 No.2

This study investigated that the effect of rewetting agent on dentinal microtensile bond strength (μTBS). Human molars were sectioned to expose the superficial dentin surfaces. Samples were divided into two groups according to type of adhesives-Single Bond (S) and One-Step (0)], and again subdivided into five groups by different dentin surface treatment-dry for 15s (D) , blot dry (BD) or dry for 15s, and rewet with different rewetting agents[distil1ed water (DW), Gluma Desensitizer (GD) and Aqua-Prep (AP)]for 30s. After application of adhesive, composite resin was built up on the bonding surface. Each tooth was sectioned to obtain stick with 1mm^(2) cross sectional area and the μTBS was determined by EZ test. In the S group, the mean μTBS of GD, AP and BD group was significantly higher than that of DW and D group (p < 0.05). In the 0 group, the mean μTBS of AP, GD, BD and DW group was significantly higher than that of D group (p < 0.05). The data suggested that Gluma Desensitizer and Aqua-Prep could be successfully used as rewetting agents, and Distilled water could be acceptable in aceton based adhesive system only.

Pickering-Emulsion-Polymerized Polystyrene/Fe₂O₃ Composite Particles and Their Magnetoresponsive Characteristics

Kim, Young Jae,Liu, Ying Dan,Seo, Yongsok,Choi, Hyoung Jin American Chemical Society 2013 Langmuir Vol.29 No.16

<P>Core–shell-structured magnetic polystyrene (PS)/inorganic particles were fabricated by Pickering emulsion polymerization using nanosized Fe<SUB>2</SUB>O<SUB>3</SUB> particles as a solid stabilizer. Scanning electron microscopy and transmission electron microscopy confirmed the synthesized PS/Fe<SUB>2</SUB>O<SUB>3</SUB> particles to be comprised of a PS surface coated with Fe<SUB>2</SUB>O<SUB>3</SUB> nanoparticles. The chemical structure of the composite nanospheres was characterized by Fourier transform infrared spectroscopy and X-ray diffraction. The thermal properties of composite nanospheres and corresponding pure polymer were examined by thermogravimetric analysis. The rheological properties of the core–shell-structured magnetic PS/inorganic particles dispersed in silicone oil were investigated under an external magnetic field strength using a rotational rheometer. The particles with extremely lower density than common magnetic particles exhibited solid-like magnetorheological phase characteristics, and the flow curves were fitted to the Cho–Choi–Jhon model of the rheological equation of state.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/langd5/2013/langd5.2013.29.issue-16/la400523w/production/images/medium/la-2013-00523w_0011.gif'></P>