• 제목/요약/키워드: R-2R

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Evaluation for Rock Cleavage Using Distribution of Microcrack Spacings (III) (미세균열의 간격 분포를 이용한 결의 평가 (III))

  • Park, Deok-Won
    • The Journal of the Petrological Society of Korea
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    • 제25권4호
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    • pp.311-324
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    • 2016
  • The characteristics of the rock cleavage in Jurassic granite from Geochang were analysed. The evaluation for three quarrying planes and three rock cleavages was performed using the parameters such as (1) reduction ratio between the value of spacing and the value of length, (2) microcrack spacing frequency(N), (3) total spacing($1mm{\geq}$), (4) exponential constant(a), (5) magnitude of exponent(${\lambda}$), (6) mean spacing($S_{mean}$), (7) difference value($S_{mean}-S_{median}$) between mean spacing and median spacing($S_{median}$) and (8) density of spacing. Especially the close dependence between the above spacing parameters and the parameters from the spacing-cumulative frequency diagrams was derived. The discrimination factors representing three quarrying planes and three rock cleavages were acquired through these mutual contrast. The analysis results of the research are summarized as follows. First, the reduction ratios of frequency(N), mean value, median value, the above difference value($S_{mean}-S_{median}$) and density for three rock cleavages are in orders of G(grain, (G1 + G2)/2) < H(hardway, (H1 + H2)/2) < R(rift, (R1 + R2)/2), H < G $\ll$ R, H < G $\ll$ R, H < G < R and H < G $\ll$ R. The values of the above five parameters for three planes show the various orders of R'(rift plane) $\ll$ H'(hardway plane) < G'(grain plane), R' $\ll$ G' < H', R' < H' < G', R' < G' < H' and R' $\ll$ H' < G', respectively. Second, the values of (I) parameters(2, 3, 4 and 5) and (II) parameters(6, 7 and 8) are in orders of (I) H < G < R and (II) R < G < H. On the contrary, the values of the above two groups(I~II) of parameters for three planes show reverse orders. Third, to review the overall characteristics of the arrangement among the six diagrams, these diagrams show an order of R2 < R1 < G2 < G1 < H2 < H1 from the related chart. In other words, above six diagrams can be summarized in order of rift(R1 + R2) < grain(G1 + G2) < hardway(H1 + H2). These results indicate a relative magnitude of rock cleavage related to microcrack spacing. Especially, two parameters for each diagram, the above difference value($S_{mean}-S_{median}$) and mean spacing, could provide advanced information for prediction the order of arrangement among the diagrams. Finally, the general chart for three planes and three rock cleavages were made. From the related chart, three exponential straight lines for three rock cleavages show an order of R(R1 + R2) < G(G1 + G2) < H(H1 + H2). On the contrary, three lines for three planes show an order of H'(R2 + G2) < G'(R1 + H2) < R'(G1 + H1). Consequently, correlation of the mutually reverse order between three planes and three rock cleavages can be drawn from the related chart.

SYMMETRIC BI-DERIVATIONS IN PRIME RINGS

  • Jung, Yong-Soo
    • Journal of applied mathematics & informatics
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    • 제5권3호
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    • pp.819-826
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    • 1998
  • The purpose of this paper is to prove the following results; (1) Let R be a prime ring of char $(R)\neq 2$ and I a nonzero left ideal of R. The existence of a nonzero symmetric bi-derivation D : $R\timesR\;\longrightarrow\;$ such that d is sew-commuting on I where d is the trace of D forces R to be commutative (2) Let m and n be integers with $m\;\neq\;0.\;or\;n\neq\;0$. Let R be a noncommutative prime ring of char$ (R))\neq \; 2-1\; p_1 \;n_1$ where p is a prime number which is a divisor of m, and I a nonzero two-sided ideal of R. Let $D_1$ ; $R\;\times\;R\;\longrightarrow\;and\;$ $D_2\;:\;R\;\times\;R\;longrightarrow\;R$ be symmetric bi-derivations. Suppose further that there exists a symmetric bi-additive mapping B ; $R\;\times\;R\;\longrightarrow\;and\;$ such that $md_1(\chi)\chi + n\chi d_2(\chi)=f(\chi$) holds for all $\chi$$\in$I, where $d_1 \;and\; d_2$ are the traces of $D_1 \;and\; D_2$ respectively and f is the trace of B. Then we have $D_1=0 \;and\; D_2=0$.

Stereospecific Coordination of 2,2$^\prime$-Diaminobiphenyl in the Square Planar Platinum(Ⅱ) Comdlexes

  • Jun, Moo-Jin;Choi, Sung-Rack
    • Bulletin of the Korean Chemical Society
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    • 제5권6호
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    • pp.237-240
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    • 1984
  • 2,2'-Diaminobiphenyl platinum (II) complexes of optically active trans-1,2-diaminocyclohexane and 1,2-diaminopropane, [Pt(S,S-chxn)(dabp)]Cl2, [Pt(R,R-chxn)(dabp)]$C_{12}$, [Pt(S-pn)(dabp)]$C_{l2}$, and [Pt(R-pn)(dabp)]Cl2, where S,S-chxn and R,R-chxn are, respectively, S and R isomers of trans-1,2-diaminocyclohexane, and S-pn and R-pn are, respectively, S and R isomers of 1,2-diaminopropane, and dabp the 2,2'-diaminobipheny, have been prepared. The dabp ligand has been found to take the $=delta$ conformation in the S,S-chxn and S-pn platinum (II) complexes, while it takes the $\lambda$ conformation in the R,R-chxn and R-pn platinum (II) complexes.

RINGS AND MODULES WHICH ARE STABLE UNDER NILPOTENTS OF THEIR INJECTIVE HULLS

  • Nguyen Thi Thu Ha
    • Bulletin of the Korean Mathematical Society
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    • 제60권2호
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    • pp.339-348
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    • 2023
  • It is shown that every nilpotent-invariant module can be decomposed into a direct sum of a quasi-injective module and a square-free module that are relatively injective and orthogonal. This paper is also concerned with rings satisfying every cyclic right R-module is nilpotent-invariant. We prove that R ≅ R1 × R2, where R1, R2 are rings which satisfy R1 is a semi-simple Artinian ring and R2 is square-free as a right R2-module and all idempotents of R2 is central. The paper concludes with a structure theorem for cyclic nilpotent-invariant right R-modules. Such a module is shown to have isomorphic simple modules eR and fR, where e, f are orthogonal primitive idempotents such that eRf ≠ 0.

Cytotoxicity of Compound K (IH-901) and Ginsenoside Rh2, Main Biotransformants of Ginseng Saponins by Bifidobacteria, against Some Tumor Cells

  • Shin, Ji-Eun;Park, Eun-Kyung;Kim, Eun-Jin;Hong, Yoon-Hee;Lee, Kyung-Tae;Kim, Dong-Hyun
    • Journal of Ginseng Research
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    • 제27권3호
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    • pp.129-134
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    • 2003
  • When ginsenoside $R_{*}$b1/ and $R_{b2}$ were anaerobically incubated with human fecal microflora, these ginsenosides were metabolized to compound K (IH-901). When ginsenoside $R_{g3}$ was anaerobically incubated with human fecal microflora, the ginsenoside $R_{g3}$ was metabolized it to ginsenoside $R_{h2}$. Among ginsenosides, IH-901 and 20(S)-ginsenoside $R_{h2}$ exhibited the most potent cyotoxicity against tumor cells: 50% cytotoxic concentrations of IH-901 in the media with and without fetal bovine serum (FBS) were 27.1-31.6 $\mu$M and 0.1-0.61 $\mu$M, and those of 20(S)-ginsenoside $R_{h2}$ were 37.5->50 and 0.7-7.1 $\mu$M, respectively. The cytotoxic potency of ginsenosides was IH-901>20(S)-ginsenoside R $h_{h2}$》20(S)-ginsenoside $R_{g3}$>ginsenoside $R_{b1}$(equation omitted) $R_{b2}$.EX>$R_{b2}$./.

ON (α,β)-SKEW-COMMUTING AND (α,β)-SKEW-CENTRALIZING MAPS IN RINGS WITH LEFT IDENTITY

  • JUNG, YONG-SOO;CHANG, ICK-SOON
    • Communications of the Korean Mathematical Society
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    • 제20권1호
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    • pp.23-34
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    • 2005
  • Let R be a ring with left identity. Let G : $R{\times}R{\to}R$ be a symmetric biadditive mapping and g the trace of G. Let ${\alpha}\;:\;R{\to}R$ be an endomorphism and ${\beta}\;:\;R{\to}R$ an epimorphism. In this paper we show the following: (i) Let R be 2-torsion-free. If g is (${\alpha},{\beta}$)-skew-commuting on R, then we have G = 0. (ii) If g is (${\beta},{\beta}$)-skew-centralizing on R, then g is (${\beta},{\beta}$)-commuting on R. (iii) Let $n{\ge}2$. Let R be (n+1)!-torsion-free. If g is n-(${\alpha},{\beta}$)-skew-commuting on R, then we have G = 0. (iv) Let R be 6-torsion-free. If g is 2-(${\alpha},{\beta}$)-commuting on R, then g is (${\alpha},{\beta}$)-commuting on R.

UPPER BOUNDS FOR ASSIGNMENT FUNCTIONS

  • Lee, Gwang-Yeon
    • Communications of the Korean Mathematical Society
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    • 제9권2호
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    • pp.279-284
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    • 1994
  • Let R = ($r_1$, $r_2$, …, $r_{m}$) and S = ($s_1$, $s_2$, …, $s_{n}$ ) be positive integral vectors satisfying $r_1$$r_2$+…+ $r_{m}$ = $s_1$$s_2$+ㆍㆍㆍ+ $s_{n}$ , and let U(R, S) denote the class of all m $\times$ n matrices A = [$_a{ij}$ ] where $a_{ij}$ = 0 or 1 such that (equation omitted) = $r_{i}$ , (equation omitted) = $s_{j}$ , i = 1, ㆍㆍㆍ, m, j = 1, ㆍㆍㆍ, n.(omitted)

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Synthesis of a Precursor of Bulgecinine, (4S,5R)-1-Acetyl-2-formyl-5-benzyloxymethyl-4-pyrrolidinol (Bulgecinine 선구물질인 (4S,5R)-1-Acetyl-2-formyl-5-benzyloxymethyl-4-pyrrolidinol의 합성)

  • Jeon, Hak Rim;Yoon, Shin Sook;Shin, Young Sook;Nam Shin, Jeong E.
    • Journal of the Korean Chemical Society
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    • 제41권3호
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    • pp.150-156
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    • 1997
  • A precursor of bulgecinine, (4S,5R)-1-acetyl-2-formyl-5-benzyloxymethyl-4-pyrrolidinol (15) has been synthesized from diacetone-D-glucose. Barton deoxygenation, conversion to an L-sugar and displacement with $N_3^-$ at C-5, and one-pot reductive cyclization at C-2 produced (6R)-6-Ο-benzyloxymethyl-(3R)-3-methoxy-2-oxa-5-azabicyclo-[2,2,1]heptane(13), a key intermediate for bulgecinine. N-Acetylation and acid hydrolysis of 13 furnished a precursor of bulgecinine, (2S,4S,5R)-pyrrolidinol derivative 15 and its (2R,4S,5R)-diastereomer.

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Direct Synthesis of ${\eta}^6$-1-Functionally Substituted 2,3,4,5-Tetraphenyl-1-Silacyclopentadiene Complexes of Chromium

  • Wan-Chul Joo;Jang-Hwan Hong;Hong Lae Sohn;Eun-Kyoung Kang;Chang-Hwan Kim
    • Bulletin of the Korean Chemical Society
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    • 제11권1호
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    • pp.31-33
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    • 1990
  • We synthesized the novel complexes of (1,1-dimethyl-3,4-diphenyl-1-silacyclopenta-2,4-di ene-2,5-yldibenzene)bis(tricarbonylchromium) and tricarbonyl (R,R'-3,4,5-triphenyl-1-silacyclopenta-2,4-diene-2 -ylbenzene)chromium(R,R' = Me, R = Me/R' = Cl, R = Ph/R' = Cl) from the reaction of the corresponding R,R'-2,3,4,5-Tetraphenyl-1-silacyclopenta-2,4-dien e (abr. R,R'-TPSCp) with chromiumhexacarbonyl. These results reveal that chromium prefer to coordinate to the phenyl substituents of 1-silacyclospentadiene rather than the butadiene moiety of the ring.