• Title/Summary/Keyword: Z1.4 - 2003

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Synthesis and Characterization of (THF)3 Li(NC)CU(C6H3-2,6-Mes2)and Br(THF)2 Mg(C6H3-2,6-Trip2) (Mes = C6H2-2,4,6-Me3; Trip = C6H2-2,4,6-i-Pr3): The Structures of a Monomeric Lower-Order Lithi

  • Hwang, Cheong-Soo;Power, Philip P.
    • Bulletin of the Korean Chemical Society
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    • 제24권5호
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    • pp.605-609
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    • 2003
  • The lower-order lithium organocyanocuprate compound, (THF)₃Li(NC)Cu($C_6$H₃-2,6-Mes₂) (1), and the bulky terphenyl Grignard reagent, Br(THF)₂Mg($C_6$H₃-2,6-Trip₂) (2), have been synthesized and structurally characterized both in the solid state by single crystal x-ray crystallography and in solution by multi-nuclear NMR and IR spectroscopy. The compound (1) was isolated as a monomeric contact ion-pair in which the C (organic ipso)-Cu-CN-Li atoms are coordinated linearly. The lithium has a tetrahedral geometry as a result of solvation by three THF molecules. The compound (1) is the first example of fully characterized monomeric lower order lithium organocyanocuprate. The bulky Grignard reagent (2) was also isolated as a monomer in which the magnesium, solvated by two THF molecules, has a distorted tetrahedral geometry. The crystals of (1) possess triclinic symmetry with the space group $P{\={1}}$, Z = 2, with a = 12.456(3) Å, b = 12.508(3) Å, c = 13.904(3) Å, α = 99.81°, β = 103.72(3)°, and γ = 119.44(3)°. The crystals (2) have a monoclinic symmetry of space group $P2_{1/C}$, Z = 4, with a = 13.071(3) Å, b = 14.967(3) Å, c = 22.070(4) Å, and β = 98.95(3)°.

SITE-DEPENDENT IRREGULAR RANDOM WALK ON NONNEGATIVE INTEGERS

  • Konsowa, Mokhtar-H.;Okasha, Hassan-M.
    • Journal of the Korean Statistical Society
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    • 제32권4호
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    • pp.401-409
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    • 2003
  • We consider a particle walking on the nonnegative integers and each unit of time it makes, given it is at site k, either a jump of size m distance units to the right with probability $p_{k}$ or it goes back (falls down) to its starting point 0, a retaining barrier, with probability $v_{k}\;=\;1\;-\;p_{k}$. This is a Markov chain on the integers $mZ^{+}$. We show that if $v_{k}$ has a nonzero limit, then the Markov chain is positive recurrent. However, if $v_{k}$ speeds to 0, then we may get transient Markov chain. A critical speeding rate to zero is identified to get transience, null recurrence, and positive recurrence. Another type of random walk on $Z^{+}$ is considered in which a particle moves m distance units to the right or 1 distance unit to left with probabilities $p_{k}\;and\;q_{k}\;=\;1\;-\;p_{k}$, respectively. A necessary condition to having a stationary distribution and positive recurrence is obtained.

Headspace solid-phase microextraction(HS-SPME)를 이용한 간의 비린내불쾌취에 기인하는 불포화지방산 산화생성물의 휘발성성분 (Volatile Compounds in the Oxidation of Unsaturated Fatty Acids Caused in Off-flavor of Porcine Liver by HS-SPME)

  • 임성임;최성희
    • 한국식품과학회지
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    • 제35권3호
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    • pp.359-365
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    • 2003
  • 간 및 간에 함유된 불포화지방산인 arachidonic, linolenic, linoleic 및 oleic acid의 철 이온 존재하에서의 headspace 산화 반응생성물을 SPME법을 이용하여 포집, 분석하는 것에 의해 간에 함유된 불포화지방산의 산화생성물과 간의 비린내 불쾌취 형성과의 관련성을 검토하였다. SPME fiber중 불포화지방산의 headspace 산화생성물인 휘발성 알데히드류, 알코올류 및 지방산 등 대다수의 화합물을 검출에는 PDMS/DVB fiber가 적합하였다. 간의 headspace 산화생성물은 arachdonic acid을 비롯한 간에 함유된 각 불포화지방산의 head-space 산화생성물과 일치하였으며, 간의 불쾌취 형성은 간에 함유된 불포화지방산의 산화로 생성되는 산화 반응생성물에 의한 것이 시사되었다. 간의 불쾌취를 형성하는 주요성분으로는, arachidonic acid에서 생성되어 간의 금속취를 형성하는 화합물로 생각되어지는 1-octen-3-one 및 hexanol과 linolenic acid에서 형성되어 간의 비린내를 형성하는 (E,E)-2,4-heptadienal이 그 원인물질인 것으로 사료된다. 산화에 의해 생성된 각 불포화지방산의 산화 반응생성물은 간의 불쾌취인 비린내, 금속취 등을 생성하며, 주로 arachidonic acid 및 linolenic acid의 산화에 의해 생성된 산화 반응생성물에 의한 것으로 밝혀졌다.

Microstructure and Microwave Dielectric Properties of (1-x) Ba (Co1/3Nb2/3)O3-zBa(Zn1/3Nb2/3)O3 Ceramics

  • Ahn, Byung-Guk;Ahn, Cheol-Woo;Nahm, Sahn;Lee, Hwack-Joo
    • 한국세라믹학회지
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    • 제40권4호
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    • pp.333-339
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    • 2003
  • Ba (Co$_{1}$ 3/Nb$_{2}$ 3/)O$_3$(BCN) has a 1:2 ordered hexagonal structure. Q-value of BCN increased with increasing sintering temperature however, it significantly decreased when the sintering temperature exceeded 140$0^{\circ}C$ Ba (Co$_{1}$ 3/Nb$_{2}$ 3/)O$_3$(BZN) has the 1:2 ordered hexagonal structure and the degree of the 1 : 2 ordering decreased with the increase of the sintering temperature. The Q value of the BZN increased with increasing the sintering temperature and BZN sintered at 140$0^{\circ}C$ for 6h has a maximum Q-value. For (1-x) Ba (Co$_{1}$ 3/Nb$_{2}$ 3/)O$_3$-zBa(Zn$_{1}$ 3/Nb$_{2}$ 3/)O$_3$[(1-x)BCN-xBZN] ceramics the 1:2 ordered hexagonal structure was observed in the specimens with x$\leq$0.3 and the BaNb$_{6}$ O$^{16}$ second phase was found in the specimens with x$\geq$0.6. Grain Growth, which is rotated to the BaNb$_{6}$ O$^{16}$ second phase occurred in the specimens with x$\geq$ 0.5. In this work, the excellent microwave dielectric properties of $\tau$r=0.0 ppm/$^{\circ}C$$\varepsilon$r=34.5 and Q,$\times$f=97000GHz sere obtained for the 0.7BCV-0.3BZN ceramics sintered at 1400$0^{\circ}C$ for 20h.

KS개정 선별형 계수이산 샘플링 검사 계획 (Revised KS Standards for Acceptance Sampling By Attribute Based On Screening)

  • 최성운
    • 대한안전경영과학회:학술대회논문집
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    • 대한안전경영과학회 2008년도 추계학술대회
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    • pp.241-246
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    • 2008
  • This paper introduces nine acceptance sampling plans by attribute based on screening (sorting, rectifying). Revised KS standards for single and double acceptance sampling by attribute such as Dodge - Romig : 1998, KSA ISO 2859 - 2 : 2001, 13448 - 1, 2, MIL - STD - 105E : 1989, KSA IEC 60410 and ANSI/ASQ Z1. 4 : 2003 are presented.

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광조사 시간에 따른 복합레진과 Ormocer의 중합수축에 관한 연구 (A STUDY OF CONTRACTION SHRINKAGE OF COMPOSITE RESINS AND ORMOCERS WITH VARIOUS CURING TIMES)

  • 정연정;민경산;이해형;조경모;조용범
    • Restorative Dentistry and Endodontics
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    • 제28권4호
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    • pp.326-333
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    • 2003
  • Ormocer has organic-inorganic compound polymers. One of advantages of ormocer is reduced polymerization shrinkage. The purpose of this study was to compare the amount of contraction shrinkage of composite resins and ormocers. Additionally, the time of each material when there is no further change of contraction shrinkage was analysed. Four brands of composite resins (P-60. Surefil, Z-250 and Denfil) and two brands of ormocers (Definite and Admira) were used. 20 seconds, 40 seconds and 60 seconds of curing times were given. Contraction shrinkage of them were measured using a linometer for 80 seconds. The effect of material and curing time to contraction shrinkage at the time of 80 seconds was analysed by two-way ANOVA. The effect of time to contraction shrinkage was analysed by one-way ANOVA and the time when there was no further change of the contraction shrinkage was analysed. The results are as follows: 1. P-60, Definite, Z-250 and Denfil had no further change of contraction shrinkage from the time of 20 seconds, and Surefil and Admira had no further change of contraction shrinkage from the time of 10 seconds. 2. Statistical analysis revealed volumetric shrinkage varied among material (p<0,05). No significant difference of contraction shrinkage among different curing times was found, and there was no effect of interaction between materials and curing times to contraction shrinkage. 3. Definite and Admira showed the statistically same contraction shrinkage with those of Z-250 and P-60. which is higher than that of Surefil and lower than that of Denfil (p<0.05).

Co계 아몰퍼스리본을 이용하여 제작한 마안더패턴의 고주파 임피던스특성 (High Frequency Impedance of Meander Pattern Fabricated by Co-base Amorphous Ribbon)

  • 신광호;박경일;사공건;송재연;김영학
    • 한국자기학회지
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    • 제13권4호
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    • pp.160-164
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    • 2003
  • 연자성이 우수한 Co계 아몰퍼스리본을 리소그래피와 에칭을 통하여 미안더타입(meande, type)의 미소패턴으로 가공하고 표피효과가 현저하게 나타나는 300 KHz∼l ㎓의 주파수영역에서 고주파임피던스, 저항, 인덕턴스에 미치는 외부자기장의 영향을 조사하였다. 제작한 아몰퍼스리본의 미안더패턴은 자기장중 열처리를 통하여 폭방향으로 자기용이축이 유도되어 있었으며 패턴의 길이방향으로 인가된 외부자기장에 대하여 민감한 임피던스의 변화를 나타내었다. 임피던스는 약 13 Oe부근의 인가자기장에서 최대값을 나타내었으며 50 MHz에서 11 Oe의 인가 자기장에 대하여 약 210%의 임피던스 변화율을 나타내었다.

4S-Van: A Prototype Mobile Mapping System for GIS

  • Lee, Seung-Yong;Kim, Seong-Baek;Choi, Ji-Hoon;Lee, Jong-Hun
    • 대한원격탐사학회지
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    • 제19권1호
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    • pp.91-97
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    • 2003
  • The design of Graphic Information System(GIS) in various applications is suffering from the difficulty of data acquisition, which is labor-intensive and time consuming. In order to provide the spatial data rapidly and accurately, 4S-Van, a prototype mobile mapping system, has been developed. The 4S-Van consists of 1)Global Positioning System(GPS), Inertial Navigation System(INS) for estimating the geographic position and attitude of the moving van, i.e.,(x, y, z) and the direction of the Van, 2) Charge Coupled Device(CCD) camera and laser scanner for capturing images and for measuring depth from geographic objects, and 3) External Synchronization Device(ESD) and industrial PC for synchronizing data from GPS/INS/CCD camera and for storing the data. In this paper, we present the design and implementation of the proto-Dpe 4S-Van system for spatial data acquisition for various GIS applications.

Involvement of Akt in mitochondria-dependent apoptosis induced by a naphthoquinone analog

  • Kang, Seung-Koo;Kim, Hae-Jong;Chun, Young-Jin;Kim, Mie-Young
    • 대한약학회:학술대회논문집
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    • 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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    • pp.158.2-158.2
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    • 2003
  • Vitamin K-related analogs induce growth inhibition in various cancer cell lines. We report that 2,3-dichloro-5,8-dihydroxy-1, 4-naphthoquinone (DDN), a naphthoquinone analog, induces mitochondria-dependent apoptosis in human promyeloid leukemic HL-60 cells. DDN induced cytochrome c release, cleavage of Bid, and activation of caspases -8, -9 and -3. Cleavage of Bid, the caspase-8 substrate, was inhibited by the broad caspase inhibitor zVAD-fmk, whereas cytochrome c release was not affected by zVAD-fmk. (omitted)

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평화의 댐 어류군집 분석 (Fish Community Analysis in the Peace Dam)

  • 이광열;장영수;최의용;서진원;최재석
    • 생태와환경
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    • 제38권3호통권113호
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    • pp.297-303
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    • 2005
  • 2003년 4월부터 2004년 9월까지 평화의댐의 어류상 및 군집분석을 조사한 결과는 다음과 같다. 조사기간동안 출현한 어류는 모두 8과 31종이었다. 채집어종들 중 한국고유종은 줄납자루 (Acheilognathus yamatsutae), 쉬리 (Coreoleuciscus splendidus) 등 13종 (41.94%)으로 나타났다. 우점종은 누치 (Hemibarbus labeo) 14.07%, 갈겨니 (Zacco temmincki) 13.72%, 피라미 (Z. platypus) 11.94%, 참마자(H. longirostris) 9.31%, 쏘가리 (Siniperca scherzeri) 8.10% 등 이었다. 생체량은 누치 (H. labeo) 24,278 g, 쏘가리 (S. scherzeri) 19,487 g, 뱀장어 (A. japonica) 10,400 g, 잉어 (C. carpio) 8,418 g, 붕어 (C. auratus) 4,020 g등의 순으로 나타났다. 어류상 및 어류군집에 따라 북한강수계의 인공호들은 UPGMA에 의해 2개의 그룹으로 나누어졌으며, 평화의 댐은 소양호 및 파로호와 비슷한 군집구조를 지닌 것으로 나타났다.