• Title/Summary/Keyword: 그라이트

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Three Crystal Structures of Dehydrated $Ag_{12-x}Na_x-A$ (x: 4, 6, and 8) Treated With Cesium Vapor (탈수한 $Ag_{12-x}Na_x-A$(x :4, 6, 및 8)를 세슘 증기로 처리한 세가지 결정구조)

  • Lee, Hyun-Do;Kim, Un-Sik;Park, Jong-Yul;Kim, Yang
    • Korean Journal of Crystallography
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    • v.4 no.2
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    • pp.63-73
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    • 1993
  • Ag+ 이온이 부분적으로 치환된 3가지 제올라이트 A(Ag4Na8-A, Ag6Na6-A 및 Ag8Na4-A)를 완전히 탈수한 후 280℃에서 24시간동안 약 0.1 Torr의 Cs중기로 처리하 였다. 이들의 결정구조는 22(1)℃ 노에서 입방공간군 Pm3m (단위세포상수 a가 각각 12.321(3) A, 12.295(1) A 및 12.380(7) A임)을 사용하여 단결정 X-선회절법으로 해석 하였다. 이들 세가지 구조에서 Cs+이온은 각각 서로 다른 4개의 결정학적 위치에서 발견되었다. 단위세포당 3개의 Cs+이온은 8-링 중심에 위치하고, 약 6.9-7.3개의 Cs+이온 은 큰 동공의 6-링과 마주보는 위치에 있는 3회 회전축상에서 발견되었다. 그리고 약 2.17-2.74개의 Cs+이온은 소다 라이트 동공내에서 발견되며 약 0.5-1.0개의 Cs+'이온은 4링과 마주보는 곳에 위치한다. 또한 이들 구조에서 단위세포당 각각 1.88(5),2.30(3) 및 5.28(10)개의 Ag종이 존재하며 이들은 큰동공의 중심에서 헥사실버 클러스트를 형성한다. 8-링위치가 Cs+이온으로 모두 차있어서 Ag0가 골조밖으로 이동하는 것을 막을 수 있다. 각각의 헥사실버 클러스터는 서로 다른 좌표에 위치하는 14개의 Cs+이온에 의해 안정화된다. 이들 구조에서 발견되는 약 12.35-13.49개의 Cs+이온들은 Cso의 흡착이 일어나 제올라이트 기본 골 격에 있는 음이온 전하와 균형을 맞출 수 있는 12개의 Cs+ 이온 이상의 이온 또는 원자로 존재하고 있다. Cs+의 배열 은 다음과 같은 두 가지 배열로 쉽게 설명할 수 있다. 일부는 2개의 Cs+이온이 소다이트 동공내에 있는 6-링과 마주보는 곳에 위치하고 큰동공내에는 6개의 Cs+이온이 6링 근처에 위치하며 1개는 4-링 근처에 위치한다. 그 나머지는 소다라이트 동공내에 위치하는 3개의 Cs+이온과 한변의 길이를 3.52 A로 갖는 삼각형을 형성한 후 6-링을 통 하여 큰 동공 내에 위치한 3개의 Cs원자와 결합하게 되므로 3m (C3v)의 대칭구조를 갖는 (CS6)4+클러스터를 형성한다. 그 밖의 5개 Cs+이온은 비어있는 큰동공의 6-링에 위치한다.

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A Study on Wasteform Properties of Spent Salt Treated with Zeolite and SAP (염화염을 제올라이트와 SAP로 처리한 고화체의 특성연구)

  • Kim, Hwan-Young;Park, Hwan-Seo;Kang, Kweon-Ho;Ahn, Byung-Gil;Kim, In-Tae
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.8 no.2
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    • pp.99-105
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    • 2010
  • This paper investigated the characteristics of wasteform containing a spent zeolite used as a separating agent of FPs for recycling LiCl waste which would be generated from pyrochemical process of spent PWR fuel. In this study, a conventional borosilicate and Ca-rich glass were used as a consolidating agent for spent zeolite and it's mixing ratio was changed in the range, $25{\sim}35wt%$. The leach rates of Cs and Sr had about $0.1{\sim}0.01g/m^2day$ and $0.001{\sim}0.0001g/m^2day$, respectively. The leach resistance of Cs increased with amount of SAP and it showed about 10 times higher in the Ca-rich glass wasteform than in the conventional borosilciate glass wasteform. The compressive strength of wasteform was affected with the amount of glass. Thermal expansion rate of containing 30wt% glass has relatively lower than others. Also, the melting temperature was little changed in given mixing ratio of glass.

Modeling Nutrient Uptake of Cucumber Plant Based on EC and Nutrient Solution Uptake in Closed Perlite Culture (순환식 펄라이트재배에서 EC와 양액흡수량을 이용한 오이 양분흡수 모델링)

  • 김형준;우영회;김완순;조삼증;남윤일
    • Proceedings of the Korean Society for Bio-Environment Control Conference
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    • 2001.04b
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    • pp.75-76
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    • 2001
  • 순환식 펄라이트재배에서 배액 재사용을 위한 양분흡수 모델링을 작성하고자 EC 처리(1.5, 1.8, 2.1, 2.4, 2.7 dSㆍm-1)를 수행하였다. 생육 중기까지 EC 수준에 따른 양액흡수량은 차이가 없었지만 중기 이후 EC가 높을수록 흡수량이 감소되는 경항을 보였다(Fig. 1). NO$_3$-N, P 및 K의 흡수량은 생육기간 동안 처리간 차이를 유지하였는데 N과 K는 생육 중기 이후 일정 수준을 유지하였으나 P는 생육기간 동안 다소 증가되는 경향을 보였다. S의 흡수량은 생육 중기 이후 모든 처리에서 급격한 감소를 보였으며 생육 후기에는 처리간에 차이가 없었다(Fig. 2). 오이의 무기이온 흡수율에서와 같이 흡수량에서도 EC간 차이를 보여 EC를 무기이온 흡수량을 추정하는 요소로 이용할 수 있을 것으로 생각되었다. 무기이온 흡수량은 모든 EC 처리간에 생육 초기에는 차이를 보이지 않았으나 생육중기 이후에는 뚜렷한 차이를 보인 후 생육 후기의 높은 농도에서 그 차이가 다소 감소되는 경향을 보였다. 단위일사량에 따른 양액흡수량과 EC를 주된 변수로 한 오이의 이온 흡수량 예측 회귀식을 작성하였는데 모든 무기이온 흡수량 추정식의 상관계수는 S를 제외한 모든 이온에서 높게 나타났는데 특히 N, P, K 및 Ca에서 높았다. S이온에서의 상관계수는 0.47로 낮게 나타났으나 각 이온들의 회귀식에 대한 상관계수는 모두 1% 수준에서 유의성을 보여 위의 모델식을 순환식 양액재배에서 무기이온 추정식으로 사용이 가능할 것으로 생각되었다(Table 1). 이를 이용한 실측치와의 비교는 신뢰구간 1%내에서 높은 정의상관을 보여 실제적인 적용이 가능할 것으로 생각되었다(Fig 3)..ble 3D)를 바탕으로 MPEG-4 시스템의 특징들을 수용하여 구성되고 BIFS와 일대일로 대응된다. 반면에 XMT-0는 멀티미디어 문서를 웹문서로 표현하는 SMIL 2.0 을 그 기반으로 하였기에 MPEG-4 시스템의 특징보다는 컨텐츠를 저작하는 제작자의 초점에 맞추어 개발된 형태이다. XMT를 이용하여 컨텐츠를 저작하기 위해서는 사용자 인터페이스를 통해 입력되는 저작 정보들을 손쉽게 저장하고 조작할 수 있으며, 또한 XMT 파일 형태로 출력하기 위한 API 가 필요하다. 이에, 본 논문에서는 XMT 형태의 중간 자료형으로의 저장 및 조작을 위하여 XML 에서 표준 인터페이스로 사용하고 있는 DOM(Document Object Model)을 기반으로 하여 XMT 문법에 적합하게 API를 정의하였으며, 또한, XMT 파일을 생성하기 위한 API를 구현하였다. 본 논문에서 제공된 API는 객체기반 제작/편집 도구에 응용되어 다양한 멀티미디어 컨텐츠 제작에 사용되었다.x factorization (NMF), generative topographic mapping (GTM)의 구조와 학습 및 추론알고리즘을소개하고 이를 DNA칩 데이터 분석 평가 대회인 CAMDA-2000과 CAMDA-2001에서 사용된cancer diagnosis 문제와 gene-drug dependency analysis 문제에 적용한 결과를 살펴본다.0$\mu$M이 적당하며, 초기배발달을 유기할 때의 효과적인 cysteamine의 농도는 25~50$\mu$M인 것으로 판단된다.N)A(N)/N을 제시하였다(A(N)=N에 대한 A값). 위의 실험식을 사용하여 헝가리산 Zempleni 시료(15%

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Study on Underwater Welding ( Report 1 ) - Its Weldability -

  • 남기우
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.19 no.1
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    • pp.63-70
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    • 1983
  • Recently, many studies for developing the underwater welding techniques have been carried out in the advanced countries as a manufacturing process and a repairing method according as a great deal of interest in development for various marine industrial fields has been gradually increased. But no study on such underwater welding is available at present in our country. In this study, underwater welding was carried out for welding of domestic structural steel plates (SM41A) of 10 mm thickness, using six types of domestic coated arc welding electrodes on a self-made gravity type underwater welding device, resulting in investigation for the underwater weldability of the domestic structural steel plates as well as for the underwater welding properties and practicability of the domestic welding electrodes.

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Occurrence Characteristics and Existing Forms of U-Th Containing Minerals in KAERI Underground Research Tunnel(KURT) Granite (한국원자력연구원 지하처분연구시설(KURT) 화강암의 U-Th 함유광물 산출특성 및 존재형태)

  • Cho, Wan Hyoung;Baik, Min Hoon;Park, Tae-Jin
    • Economic and Environmental Geology
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    • v.50 no.2
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    • pp.117-128
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    • 2017
  • Occurrence characteristics and existing forms of U-Th containing minerals in KURT (KAERI Underground Research Tunnel) granite are investigated to understand long-term behavior of radionuclides in granite considered as a candidate rock for the geological disposal of high-level radioactive waste. KURT granite primarily consists of quartz, feldspar and mica. zircon, REE(Rare Earth Element)-containing monazite and bastnaesite are also identified. Besides, secondary minerals such as sericite, microcline and chlorite including quartz vein and calcite vein are observed. These minerals are presumed to be accompanied by a post-hydrothermal process. U-Th containing minerals are mainly observed at the boundaries of quartz, feldspar and mica, mostly less than $30{\mu}m$ in size. Quantitative analysis results using EPMA (Electron Probe Micro-Analyzer) show that 74.2 ~ 96.5% of the U-Th containing minerals consist of $UO_2$ (3.39 ~ 33.19 wt.%), $ThO_2$ (41.61 ~ 50.24 wt.%) and $SiO_2$ (15.43 ~ 18.60 wt.%). Chemical structure of the minerals calculated using EPMA quantitative analysis shows that the U-Th minerals are silicate minerals determined as thorite and uranothorite. The U-Th containing silicate minerals are formed by a magmatic and hydrothermal process. Therefore, KURT granite formed by a magmatic differentiation is accompanied by an alteration and replacement owing to a hydrothermal process. U-Th containing silicate minerals in KURT granite are estimated to be recrystallized by geochemical factors and parameters such as temperature, pressure and pH owing to the hydrothermal process. By repeated dissolution/precipitation during the recrystallization process, U-Th containing silicate minerals such as thorite and uranothorite are formed according to the variation in the concentrated amount of U and Th.

Dealumination of $NH_4Y$-Zeolite to Convert to the Hydrophobic Zeolite by High-Temperature Steam Treatment (소수성 제올라이트로의 변환을 위한 고온 수증기처리에 의한 $NH_4Y$-제올라이트의 탈알루미늄)

  • Kim, Jin-Young;Jeon, Dong-Hwan;Chung, Byung-Hwan;Mo, Se-Young
    • Journal of Korean Society of Environmental Engineers
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    • v.27 no.4
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    • pp.420-430
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    • 2005
  • This study was performed to change the hydrophilic $NH_4Y$-zeolite to the hydrophobic one for removal of VOCs by removing the $Al^{3+}$ in the zeolite-structure to increase the Si/Al ratio, for which the three pelleted $NH_4Y$-zeolite samples were contacted separately with the steam of $400^{\circ}C$, $500^{\circ}C$ and $600^{\circ}C$, respectively, in a stainless steel column for 4 hours. Then extraction of the ex-structure aluminum of the hydrolyzed zeolites with the nitric acids of 0.25, 0.50, 0.75, and 0.10 M at $90^{\circ}C$ in 500 mL-flasks, respectively, according to steam temperature were followed. XRD analysises of the dealuminated zeolites showed that the peaks of the zeolites that had been hydrolyzed with the steams of both $500^{\circ}C$ and $600^{\circ}C$ are distorted more with the increase of the concentration of nitric acid used for extraction of the ex-structure aluminums, however, those hydrolyzed with steam of $400^{\circ}C$ became amorphous phase when treated with the all nitric acids of four concentrations. Also the EDX analysises showed that the BET surface areas and TPVS of the zeolites that had been hydrolyzed with the steam of $600^{\circ}C$ were increased with the concentration of the nitric acid when the nitric acids of 0.25 M and 0.5 M had been used but decreased when the nitric acids of 0.75 M and 1.0 M had been used. These results led to the conclusion that both the $600^{\circ}C$ and $500^{\circ}C$-steam and the 0.5 M-nitric acid are appropriate to change the hydrophilic $NH_4Y$-zeolites to the hydrophobic one, which were proven by the measurement of the benzene and tolune-adsorbing capacities showing the same trend as the BET surface area and TPV The Si/Al ratios and water-adsorbing capacities of the dealuminated zeolites were increased and decreased, respectively, with the concentration of the nitric acids so that it showed that the hydrophobicity is increased.

Studies on the Nutri-Culture of Major Wild Vegetable Ligularia fischeri Turcz I. Growth and Yield of Ligularia fischeri Turcz. by Media, Amount of Media and Planting Density in Nutri-Culture (곰취의 양액재배 기술 개발 I. 배지종류 , 배지량 , 재식밀도에 따른 곰취의 생육 및 수량)

  • 홍정기
    • Korean Journal of Plant Resources
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    • v.10 no.4
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    • pp.401-410
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    • 1997
  • This experiment was conducted to investigate the opimum media, media amount and planting density of nutri-culture for the high quality and yield of wild vegetable, Liguliaria fischeri Turez. The fried rice hull was recognized best media among perlite, sand and fried rice hull for nutri-culture of Ligularia fischeri Turcz. The yield on fried rice hull media at early growing stage was lower, but higher than in other media at late growing stage. Therefore, total yield in fried rice hull media was 15-29% higher than that of the existing perlite media. Growth and yield of Ligularia fischeri Turcz. were not significantly different between medium amounts, therefore considering economical efficiency and stability, the optimum medium amount was 105 $\iota/m^3$, Yield by planting density increased in the high density and 50 plants/$m^2$ was considered as proper planting density in nutri-culture of Liguliaria fishcheri Turcz.

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Two Crystal Structures of Dehydrated $Ag^+$ and $Rb^+$ Exchanged Zeolite A, $Ag^{12-x}Rb_{x}-A$, x = 2 and 3 ($Ag^+$ 이온과 $Rb^+$ 이온으로 치환된 제올라이트 A ($Ag^{12-x}Rb_{x}-A$, x = 2 및 3) 를 탈수한 결정구조)

  • Yang Kim;Seong Hwan Song;Duk Soo Kim;Young Wook Han;Dong Kyu Park
    • Journal of the Korean Chemical Society
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    • v.33 no.1
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    • pp.18-24
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    • 1989
  • Two crystal structures of dehydrated $Ag^+$ and $Rb^+$ exchanged zeolite A, stoichiometries of $Ag_{9}Rb_{3}-A$ (a = 12.278(2)${\AA}$) and $Ag_{10}Rb_{2}-A$ (a = 12.286(2)${\AA}$) per unit cell, have been determined by single crystal x-ray diffraction techniques. Their structures were solved and refined in the cubic space group Pm3m at 21(1)$^{\circ}$C. The crystals of $Ag_{10}Rb_{2}-A$ and $Ag_{10}Rb_{2}-A$ were prepared by flow methods using exchanged solution in which mole ratios of AgNO$_3$ and RbNO$_3$ were 1:5 and 1:50, respectively, with the total concentration of 0.05 M. The structures of the dehydrated $Ag_{9}Rb_{3}-A$ and the $Ag_{10}Rb_{2}-A$ were refined to the final error indices, $R_1$ = 0.064 and $R_2$ = 0.060 with 291 reflections, and $R_1$ = 0.063 and $R_2$ = 0.080 with 416 reflections respectively, for which I >3${\sigma}$(I). In both structures, one reduced silver atom per unit cell was found inside the sodalite cavity. It may be present as a hexasilver cluster in 1/6 of the sodalite units or as an isolated Ag atom coordinated to 4 $Ag^+$ ions in each sodalite unit to give $(Ag_5)^{4+}$, symmetry 4 mm. In the structure of dehydrated $Ag_{9}Rb_{3}-A$, 8 $Ag^+$ ions lie on the threefold axis and each is nearly at the center of the 8-rings at the sites of $D_{4h}$ symmetry. In the structure of dehydrated $Ag_{10}Rb_{2}-A$, two crystallographically different eight 6-ring $Ag^+$ ions were found; $7Ag^+$ ions in the (111) planes of their O(3) framework oxygens and one $Ag^+$ ion inside of sodalite cavity. Two crystallographically different 8-ring cations were also found; two $Rb^+$ ions at the centers of the 8-oxygen rings and one $Ag^+$ ion into the large cavity. Both structures indicate that $Rb^+$ ions prefer to occupy the 8-ring sites, while $Ag^+$ ions prefer to occupy the 6-ring sites.

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Study on the High Temperature Properties of Fireproof Mortar Using Various Types of Fine Aggregate (잔골재 종류에 따른 내화피복용 모르타르의 고온 성상에 관한 연구)

  • Lim, Seo-Hyung
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.2 no.2
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    • pp.100-106
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    • 2014
  • High strength concrete has a structural advantage as well as superior usability and durability, so that its application in building is being steadily augmented. However, in the high temperature like in a fire, the high strength concrete has extreme danger named explosive spalling. It is known that the major cause of explosive spalling is water vapour pressure inside concrete. General solution for preventing concrete from spalling include applying fire protection coats to concrete in order to control the rising temperature of members in case of fire. The purpose of this study is to investigate the high temperature properties of fireproof mortar using organic fiber and various types of fine aggregate for fire protection covering material. The results showed that addition of perlite and polypropylene fiber to mortar modifies its pore structure and reduces its density. This causes the internal temperature to rise. As a results, it is found that a new fireproof mortar can be used in the fire protection covering material in high strength concrete.

A study on Director of Photography Roger Deakins - Focusing on , , (촬영감독 로저디킨스의 촬영스타일 연구 -<노인을 위한 나라는 없다>, <비겁한 로버트포드의 제시제임스 암살>, <블레이드러너 2049>를 중심으로)

  • Yoo, Jae-Eung
    • The Journal of the Convergence on Culture Technology
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    • v.5 no.1
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    • pp.275-280
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    • 2019
  • Roger Deakens is one of the best director of photography in the world. He has been worked with Joel Coen & Ethan Coen since (1991). He was nominated for Academy award 13 times. At last, he won the 2018 Academy Award for Best Pictures of the Year. This article aim to look at his style of photography, which he has consistently pursued, and how he controls and implements light. Focusing on The Assassination of Jess James by the coward Robert Ford>,, .