• 제목/요약/키워드: Jeol

검색결과 138건 처리시간 0.029초

Controlled Synthesis of Hexagonal Boron Nitride on Cu Foil Using Chemical Vapor Deposition

  • Han, Jaehyun;Lee, Jun-Young;Kwon, Heemin;Yeo, Jong-Souk
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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    • pp.630-630
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    • 2013
  • Recently, atomically smooth hexagonal boron nitride(h-BN) known as a white graphene has drawn great attention since the discovery of graphene. h-BN is a III-V compound and has a honeycomb structure very similar to graphene with smaller lattice mismatch. Because of strong covalent sp2bonds like graphene, h-BN provides a high thermal conductivity and mechanical strength as well as chemical stability of h-BN superior to graphene. While graphene has a high electrical conductivity, h-BN has a highly dielectric property as an insulator with optical band gap up to 6eV. Similar to the graphene, h-BN can be applied to a variety of field, such as gate dielectric layers/substrate, ultraviolet emitter, transparent membrane, and protective coatings. However, up until recently, obtaining and controlling good quality monolayer h-BN layers have been too difficult and challenging. In this work, we investigate the controlled synthesis of h-BN layers according to the growth condition, time, temperature, and gas partial pressure. h-BN is obtained by using chemical vapor deposition on Cu foil with ammonia borane (BH3NH3) as a source for h-BN. Scanning Transmission Electron Microscopy (STEM, JEOL-JEM-ARM200F) is used for imaging and structural analysis of h-BN layer. Sample's surface morphology is characterized by Field emission scanning electron microscopy (SEM, JEOL JSM-7100F). h-BN is analyzed by Raman spectroscopy (HORIBA, ARAMIS) and its topographic variations by Atomic force microscopy (AFM, Park Systems XE-100).

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졸-겔 공정으로 합성된 코디어라이트를 이용하여 알루미나의 표면개질 (Surface Modification of Alumina Ceramic with Mg2Al4Si5O18 Glass by a Sol-Gel Process)

  • 최필규;추민철;배동식
    • 한국재료학회지
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    • 제24권1호
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    • pp.48-52
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    • 2014
  • The Mg-enriched magnesium aluminum silicate (MAS) glass is known for its higher mechanical strength and chemical resistance. Among such glasses, cordierite ($Mg_2Al_4Si_5O_{18}$) is well known to have a low thermal expansion and low melting point. Polycrystalline engineering ceramics such as alumina can be strengthened by a surface modification with low thermal expansion materials. The present study involves the synthesis of cordierite by a sol-gel process and investigates the effect of glass penetration on the surface of alumina. The cordierite powders were prepared from $Al(OC_3H_7)_3$, $Mg(OC_2H_5)_2$ and tetraethyl orthosilicate by hydrolysis and condensation reaction. The cordierite powders were characterized by X-ray diffraction (XRD, Rigaku), scanning electron microscope (SEM, JEOL: JSM-5610), energy dispersive spectroscopy (EDS, JEOL: JSM-5610), and universal testing machine (UTM, INSTRON). The X-ray diffraction patterns showed that the synthesized particles were ${\mu}$-cordierite calcined at $1100^{\circ}C$ for 1 h. The shape of synthesized cordierite was changed from ${\mu}$-cordierite to ${\alpha}$-cordierite with increasing calcination temperature. Synthesized cordierite was used for surface modification of alumina. Cordierite powders penetrated deeply into the alumina sample along grain boundaries with increasing temperature. The results of surface modification tests showed that the strength of the prepared alumina sample increased after surface modification. The strength of a surface modified with synthesized cordierite increased the most, to about 134.6MPa.

한글 종가 조리서로 추측되는 「봉접요람」의 의미와 내용 (Significance and Content of 「Bongjeopyoram」 Based on the Cookbook of Jongga in Hangeul)

  • 한복려;정혜경;정라나;이소영
    • 한국식생활문화학회지
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    • 제32권6호
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    • pp.498-512
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    • 2017
  • The aim of this study was to introduce the foods recorded in "Bongjeopyoram", a cookbook, of which the date of production and author are unknown. This was described in an old document belonging to the Hansan Lee family clan from Chungcheongnam-do and revealed its content and significance in the food culture history of Korea to academia for the first time, A close examination of "Bongjeopyoram" showed that, as with other cookbooks from the Joseon Dynasty, it started with methods of making alcoholic beverages. This was followed by recipes for different types of food in the following order: rice cakes and confectioneries, jeol-sik (seasonal foods), daily meals, foods made for jesa (ancestral rites) or a feast, food for weddings, and food for sijeol-jesa (seasonal ancestral rites). The book contained a total of 18 types of alcoholic beverages, 11 types of rice cakes and confectioneries, 20 types of daily meals, 28 types of jeol-sik and food for sijeol-jesa, 12 types of food for jesa and feasts, and 37 types of food for weddings, for a total of 126 types of food and beverages. "Bongjeopyoram" was an ancient cookbook with detailed records on how to carry out jesa, which was an important event hosted by jonggas, or the head family of a family clan, and how to receive and serve guests in the Joseon period. This book is expected to play a valuable role as a guidance with significance as a cookbook of a jongga from the Joseon Dynasty, a time when bongjesajeopbingaek (hosting jesa for one's ancestors and serving one's guest) was considered important.

조선후기 경상감사 도임행차 재현을 위한 의물 연구 : 절·월 및 일산을 중심으로 (A Study on the Uimul for Reproduction of Gyeongsang-Gamsa Doim Procession in the late Joseon Dynasty: Jeol, Wol, and Ilsan)

  • 이은주;김미경
    • 지역과문화
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    • 제7권2호
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    • pp.133-154
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    • 2020
  • 영조대 경상감사였던 조재호의 『영영일기(嶺營日記)』와 조선시대 전라감사였던 유희춘의 『미암일기초(眉巖日記草)』 등을 참고하여 조선후기 경상감사의 도임행차 준비과정과 행차에 수반되는 주요 의물을 살펴보았다. 삼망제도(三望制度)에 의해 감사 임명을 받은 자는 부임지로 떠나기 전 왕에게 감사와 하직의 인사를 드리는 사은(謝恩)과 사조(辭朝) 절차를 거쳤다. 교서(敎書)와 유서(諭書)는 왕으로부터 받았으나, 경우에 따라 승정원에서 받거나, 승정원의 서리가 부임지로 가져다 주었다. 어압이 찍힌 밀부(密符)는 유서와 함께 받았으며, 추후 반납하였다. 감사의 행차는 교인소로 가는 교인식 이전 행차와 교인식 이후 감영으로 향하는 행차, 순력행차로 구별되는데 교인식 이전 행차는 교인식 이후 도임행차에 비해 소략하게 이루어졌음을 확인하였다. 관원의 행차에 기본적으로 필요한 일산, 왕으로부터 내려받은 교서와 유서, 절·월, 밀부, 전임감사로부터 인계받는 관인과 병부를 살펴보았다. 감사에게는 통치권을 의미하는 '절(節)'과 살생권을 의미하는 '월(鉞)'이 주어졌다. 수기(手旗)로 알려져 있는 절은 투공된 육각형 입체이며, 월은 삼지창 형태임을 확인하였다. 일산은 흰색으로, 우산 살 6개에 각각 유소를 두 줄로 드리웠음을 알 수 있었다. 조선후기 경상감사 도임 행차를 교인식 이전과 이후로 나누어 도임준비 과정과 도임과정에 등장하는 의물에 대해 살펴본 연구의 결과는 감사 도임과정의 이해에 도움이 될 것으로 생각한다. 지역전통문화 재현행사에 의주를 중심으로 의미나 절차에 대한 이해도 중요하지만 시각적으로 보여줄 수 있는 기물 제작도 그에 못지 않게 중요하므로 '경상감사 도임순력행차' 및 '교인식 재현'행사 등 관아 관련 전통문화 재현행사의 기초자료로 활용할 수 있을 것으로 기대한다.

Plasma CVD 법에 의한 ITO 박막제작

  • 김형근;박연수;곽민기;장경동;손상호;이상윤;이상걸
    • 한국재료학회:학술대회논문집
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    • 한국재료학회 1994년도 추계 학술발표 강연 및 논문 개요집
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    • pp.86-86
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    • 1994
  • 박막 EL소자의 투명전극으로 제작된 ITO막의 전기적, 광학적 특성을 조사하였다. Plama CVD방법으로 제작된 ITO막은 증착시 산소결핍으로 인한 비 다량결합(non-stochiometry) 에 의해 In이 석출되어 흑화현상이 일어나 전기전도도와 광투과율을 향상을 위해 산소분위기에서 30$0^{\circ}C$로 4분간 열처리를 행하였다. 한편 ITO막의 비저항 $\rho$와 광투과율 T를 Van der pauw법과 단색 분광계로 각각 측정하였다. 그 결과 상온에서 10-15$\Omega$/$\square$의 면저항과 400-1000nm의 파장영역에서 85-95%의 광투과율을 가져 박막 EL소자의 투명전극 조건을 만족하였다. 열처리에 대학 ITO막의 구조적 특성을 알아보기 위해 X-선회절장치(JEOL.JDX-8030)로 조사하였다. Fig.1은 X-선 회절 패턴을 나타낸다. 열처리후 ITO막은 상대적으로 최대 강도(peak intensity) 가 증가함으로써 열처리에 의해 결정성 향상이되었음을 알수 있다. Fig.2는 파장에 따른 ITO막의 광투과도를 나타낸다.

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Amino acid Thiohydantoin 유도체(誘導體)의 질량분석(質量分析) (제 I 보)(第 I 報) (Mass Spectrometric Identification of Thiohydantoins Derived from Amino Acids (I))

  • 송경덕
    • 한국식품영양과학회지
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    • 제3권1호
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    • pp.53-68
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    • 1974
  • The thiohydantoin derivative derived from amino acid was used for the stepwise sequence analysis of peptide or protein from the carboxyl termini. Recently, SUZUKI reported the mass spectrometric identification about a part of these compounds. In this paper, was described the mass spectrometric identification of thiohydantoins derived from 20 amino acids. Mass spectra were obtained with a mass spectrometer, JEOL model JMS-06H and samples were introduced with a direct inlet probe. The molecular ion peaks and fragment ion peaks were identified easily, because these peaks appeared differently every amino acids and specially, it was easy discrimination between leucine and isoleucine. It is suggested that mass spectrometry was one of the useful methods to identify thiohydantoins derived from amino acids.

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THE STUDY ON THE MICROCRYSTAL GROWTH OF SILVER HALIDE IN PHOTOGRAPHIC EMULSION WITH MODIFIERS

  • Kang, Tai-Sung;Ahn, Hong-Chan;Park, In-Yeong;Kim, Chan-Rae
    • Journal of Photoscience
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    • 제1권1호
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    • pp.63-66
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    • 1994
  • Silver chlorobromoiodide cubic seed emulsion was prepared'in the presence of ammonia and phenylcarbamyl gelatin solution. When benzenethiosulfonate sodium salt (BTS) and 4-hydroxy6-methyl-1,3,3a,7-tetraazaindene (TAI), as growth modifiers, were added in the seed emulsion, the silver halide microcrystals were obtained in the forms of cubo-octahedrons, octahedrons, rhombic dodecahedron by variation of pAg value through controlled double jet. The crystal habits and shapes were determined by means of X-ray diffraction (D/MAX BIB, Rigaku) and electron microscopy (JSM-840, JEOL), respectively.

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우리나라 조우삽관과 의상적배경

  • 권영숙
    • 복식
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    • 제21권
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    • pp.129-142
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    • 1993
  • We priority given to Jowoo-Kwan this study examined the ideologic backgrounds which had influences on Jowwo-Kwan throughout the Birds Worship Thought and the Yin-Yang and Five-Elements Thought. Jowoo-Kwan with bird-feathers to Jeol-Poong namely the orgin of the Korean Kwan-Mo existed as a northern cultural elements until the Three States. The customs of Joo-Kwan were greatly related to the hunting life of a horse-riding people and they were dominated the Birds Worship Ideology originated from the primitive religion of a northern people namely Shamanism. In the early days Jowoo-Kwan with natural bird-feathers was decorated with golden bird-feathers with the development of a so-ciety and it changed realistic and crative in the form. The results that Jowoo-Kwan is applied to the Yin-Yang and Five-Elements Thought as follows. The Higher front part represents Yang and on the other hand the lower back part does Yin. Thus Jo-woo-kwan consists of a ideologic Yin-Yang. By means of principles of the Five Elements Birds are included in four animals with the mean of God and especially we can confirm it from a red bird. Expresions of Jowoo-Kwan shows the influences of the Five Elements thought.

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Image Noise Reduction Using Structural Mode Shaping for Scanning Electron Microscopy

  • Hamochi, Mitsuru;Wakui, Shinji
    • International Journal of Precision Engineering and Manufacturing
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    • 제9권2호
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    • pp.28-33
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    • 2008
  • In a scanning electron microscope (SEM), outside acoustic noise causes image noise that distorts observations of the specimen being examined. A SEM that is less sensitive to acoustic noise is highly desirable. This paper investigates the image noise problem by addressing the mode shapes of the base plate and the transmission path of the acoustic noise and vibration. By arranging the position of the rib, a new SEM base plate was developed that had twisting as the 1st and 2nd modes. In those two twisting modes, vibration nodes existed near the center of the base plate where the specimen chamber is placed. Less vibration was transmitted to the chamber and to the specimen by the twisting modes compared to bending ones, which are the 2nd and 3rd modes for a rectangular plain base plate. An SEM with the developed base plate installed exhibited a significant reduction of image noise when exposed to acoustic noises below 250 Hz.

여자 고등학생들의 지방 구분선에 따른 체형 특성 분석 (Analysis of Somatotype Characteristic according to Dividing Line of District on High School Girls)

  • 임영문;황영섭;방혜경
    • 대한안전경영과학회지
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    • 제9권5호
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    • pp.37-41
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    • 2007
  • There are two parts(middle and southern) according to dividing line of district in Korea. Middle part contains Kang Won, Chung Chung, Gyeong Gi, Seoul, In Cheon and Dae Jeon. Southern part contains Gyeong Sang, Jeol La, Je Ju, Bu San, Dae Gu, Ul San, and Gwang Ju. It is known that there are some differences between middle and southern part on weather. The climatic differences might affect human body. Thus, the mall objective of this study is to analyze effects of climatic differences which influence somatotype characteristics on residents in two regions. In order to compare and analyze data, $R\ddot{o}hrer$ index and drop-value were used. Also, this paper provides typical ratios according to dividing line of district.