• 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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    • v.24 no.5
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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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    • v.32 no.4
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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.

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

  • Im, Sung-Im;Choi, Sung-Hee
    • Korean Journal of Food Science and Technology
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    • v.35 no.3
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    • pp.359-365
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    • 2003
  • Headspace solid-phase microextraction(HS-SPME) was used to isolate the off-flavor volatile compounds, which are formed during the oxidation of porcine liver and unsaturated fatty acids in porcine liver induced by iron. Three fibers for HS-SPME method development were tested, and the polydimethylsiloxane/divinylbenzene(PDMS/DVB) fiber was selected as providing the best detection of analyzed compounds. In the oxidized arachidonic acid, the major compounds identified were hexanal, 1-octen-3-one(metallic), (Z)-4-heptenal, (E)-2-octenal, 1-octen-3-ol(mushroom), (Z)-2-nonenal (cardboard-like), and (E,E)-2,4-decadienal(fatty, oily). In the oxidized linolenic acid, the major ones were (E,E)-2,4-heptadienal(fishy), (E,E)-3,5-octadien-2-one and (E,Z)-2,6-nonadienal. Moreover, those of th oxidized porcine liver with iron were hexanal, 1-octen-3-one, (Z)-4-heptenal, (E,Z)-2,4-decadienal and (E,E)-2,4-decadienal. These results showed that the fishy and metallic off-flavor in porcine liver were due to the oxidation of unsaturated fatty acids in porcine liver.

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
    • Journal of the Korean Ceramic Society
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    • v.40 no.4
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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.

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

  • Choi, Sung-Woon
    • Proceedings of the Safety Management and Science Conference
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    • 2008.11a
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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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A STUDY OF CONTRACTION SHRINKAGE OF COMPOSITE RESINS AND ORMOCERS WITH VARIOUS CURING TIMES (광조사 시간에 따른 복합레진과 Ormocer의 중합수축에 관한 연구)

  • Chung, Yeon-Chung;Min, Kyung-San;Lee, Hae-Hyoung;Cho, Kyung-Mo;Cho, Yong-Bum
    • Restorative Dentistry and Endodontics
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    • v.28 no.4
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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).

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

  • Shin, Kwang-Ho;Park, Kyung-Il;Geon, Sa-Gong;Song, Jae-Yeon;Kim, Young-Hak
    • Journal of the Korean Magnetics Society
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    • v.13 no.4
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    • pp.160-164
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    • 2003
  • The external magnetic field dependency of the impedance, resistance, and inductance of the meander pattern fabricated by using Co-base amorphous ribbon has been investigated in the frequency range of 300 ㎑∼1 ㎓. The amorphous ribbon was patterned to the meander pattern through conventional photolithography and wet etching process. The extremely high sensitivity in impedance changing ratio by external magnetic field was observed. This is due to the transverse magnetic anisotropy the pattern which was induced by magnetic field annealing. The impedance had peak value at the external field of -13 Oe and the impedance changing ratio 100 ${\times}$ (Z$\_$13/-Z$\_$0/)/Z$\_$0/) was about 210% at the frequency of 50 MHz.

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

  • Lee, Seung-Yong;Kim, Seong-Baek;Choi, Ji-Hoon;Lee, Jong-Hun
    • Korean Journal of Remote Sensing
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    • v.19 no.1
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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
    • Proceedings of the PSK Conference
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    • 2003.10b
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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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Fish Community Analysis in the Peace Dam (평화의 댐 어류군집 분석)

  • Lee, Kwang-Yeol;Jang, Young-Su;Choi, Eui-Yong;Seo, Jin-Won;Choi, Jae-Seok
    • Korean Journal of Ecology and Environment
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    • v.38 no.3 s.113
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    • pp.297-303
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    • 2005
  • The analysis of fish community structure in the Peace Dam, Korea, was investigated from April 2003 to September 2004. Eight families and 31 species were collected during the period surveyed. Korean endemic species were 13 and the relative abundance was 41.9% of the total, along with Hemibarbus mylodon, Acheilognathus yamatsutae and Coreoleuciscus splendidus. Dominant was Hemibarbus labeo (14.1%) and subdominant species was Zacco temmincki (13.7%). Also, Z. platypus (11.9%), H. longirostris (9.3%), and Siniperca scherzeri (8.1%), were numerous. The biomass of collected fishes were H. labeo (24,278 g), S. scherzeri (19,487 g), Anguilla japonica (10,400 g), Cyprinus carpio (8,418 g), and Carassius auratus (4,020 g), According to the community analyses, the artificial reservoir with in the Bukhan River system were divided into 2 groups by unweighted pair-group method analysis (UPGMA), and it revealed that the community structure in Peace Dam was similar to those in Soyang and Paro Reservoirs.