• Bulletin of the Korean Chemical Society
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• v.20 no.1
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• pp.85-88
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• 1999

Me3NO selectively abstracts the proton from [IrH(CO)(PPh3)2L(A)]0.1+,2+ (1) (A: -CCPh, Cl-, CH3CN and L: CH3CN, Cl-, C1O4-) to give the trans-elimination products, Ir(CO)(PPh3)2(A) (2). The reductive elimination of H+ and Cl- from Ir(H)Cl2(CO)(PPh3)2 (lb) to give IrCl(CO)(PPh3)2 (2b) is first order in both lb and Me3NO. The rate law d[2b]/dt=kobs[lb]=k2[lb][Me3NO] suggests the formation of (PPh3)2(CI)2(CO)Ir-H-ON+Me3 in the rate determining step (k2) followed by the fast dissociation of both H-ON+Me3 and the trans ligand Cl-. The rate significantly varies with the cis liaand A and the trans ligand L and is slower with both A and L being Cl- than other ligands. Me3NO selectively eliminates CO from [Ir(H)2(CO)(PPh3)2L]0,+ (3) (L=CH3CN, C1O4-) to produce [Ir(H)2(PPh3)2L'(CH3CN)]+ (4) (L'=CH3CN, PPh3) in the presence of L. Me3NO does not readily remove either H+ or CO from cis, trans- and trans, trans-lr(H)(-CCPh)2(CO)(PPh3)2 and cis, trans-Ir(H)2Cl(CO)(PPh3)2. The choice whether hydridocarbonyls, 1 and 3 undergo the deprotonation or decarbonylation may be understood mostly in terms of thermodynamic stability of the products and partly by kinetic preference of Me3NO on proton and CO.

• The Transactions of the Korea Information Processing Society
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• v.7 no.12
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• pp.3986-3994
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• 2000

A multiple vector reductive processing occurs during the vector inner product operation ([C] = [A] $\bigodot$,$\square$ [B]) and proceeds at the hardware dyadic pipeline unit. Every scalar result has to be generated with the component merging delay time in the multiple vector reduction($\bigodot$). In this paper we propose a new design method by which the component merging time could be eliminated from the multiple reduction and the scalar results from the reduction($\bigodot$) could be generated nearly in the almost same condensed time as the input components are fel>ded in the dyadic pipeline unitlo) or the output components are drained out of the dyadic pipeline unit($\square$), so called a dedicated chained pipeline unit for only a inner product operation.

• Advances in environmental research
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• v.3 no.4
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• pp.293-306
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• 2014

The present study primarily focuses on the evaluation of the comparative effect of chemical coagulation and ultrasonication for elimination of aromatic amines (AAs) present in anaerobically pretreated textile wastewater containing different types of dyes including azo dyes. Color and COD reduction was also monitored at the optimized conditions. The production of AAs was measured spectrophotometrically in the form of total aromatic amines (TAAs) and also verified with high performance liquid chromatography (HPLC) selectively. A composite coagulant, magnesium chloride (MC) aided with aluminium chlorohydrate (ACH) in an equal ratio (MC + ACH) was utilized during the coagulation process, which yielded 31% of TAAs removal along with 85% of color and 52% of COD reduction. At optimized power (200 W) and sonication time (5 h), an appreciable TAAs degradation efficiency (85%) was observed along with 51% color reduction and 62% COD removal using ultrasonication. The chromatographic data indicate that sulphanilic acid and benzidine types of aromatic amines were produced after the reductive cleavage of utilized textile dyes, which were effectively mineralized after ultrasonication. The degradation followed the first order kinetics with a correlation coefficient ($R^2$) of 0.89 and a first-order kinetic constant (k) of $0.0073min^{-1}$.

• Journal of Soil and Groundwater Environment
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• v.9 no.2
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• pp.11-19
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• 2004

Chlorinated and nitroaromatic compounds are non-degradable substances that are extremely toxic and are known to be carcinogens and mutation causing agents. Moreover, the half-lives of substances such as carbon tetrachloride, hexachloroethane and nitroaromatic compounds are several decades. In this study, the optimal conditions to detoxify chlorinated compounds by the reductive degradation were investigated. The following results were obtained in the reductive degradation of CCl$_4$, C$_2$Cl$\_$6/, C$_2$HCl$\_$5/, C$_2$Cl$_4$, and C$_2$HCl$\_$5/ by using Fe, FeS and FeS$_2$ as mediators. CCl$_4$ was reduced to CH$_2$Cl$_3$ and CH$_2$Cl$_2$in anaerobic conditions when FeS was used as a mediator. While the reduction of CCl$_4$ to CHCl$_3$ was rapidly proceeded, the reduction of CHCl$_3$ to CH$_2$Cl$_2$ was occurred slowly. Further reduction to CH$_3$Cl was not observed. Unlike CCl$_4$, C$_2$Cl$\_$6/ was degraded to C$_2$HCl$\_$5/, C$_2$Cl$_4$. C$_2$HCl$_3$ and cis-1,2-C$_2$H$_2$Cl$_2$ by complicated pathways such as hydrogenolysis, dehalo-elimination and dehydrohalogenation. A small amount of C$_2$HCl$\_$5/ was detected only in the early stages of the reduction. However, majority of the C$_2$Cl$\_$6/ was reduced to C$_2$Cl$_4$. cis-1,2-C$_2$H$_2$C1$_2$ was the only product among other possible isomers.

• YAKHAK HOEJI
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• v.36 no.6
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• pp.591-597
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• 1992

The organ distribution of $[^3H]$-methotrexate-lactosaminated bovine serum albumin conjugates ($[^3H]$-MTX-LBSA) was investigated to examine their role as a liver-specific anticancer drug. Synthesis of lactosaminated bovine serum albumin(LBSA) with BSA, lactose and sodium cyanoborohydride through reductive amination was followed by its conjugation with methotrexate (MTX) and 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC), thereby synthesizing [$[^3H]$-MTX-LBSA conjugates. Organ distribution and plasma elimination profiles were studied in male Wistar rats after intravenous injection of [$[^3H]$-MTX-LBSA conjugates. The fates of $[^3H]$-MTX and the $[^3H]$-MTX-BSA conjugates´fates were also investigated for comparison. The results showed that the plasma level of $[^3H]$-MTX-LBSA conjugates declined more rapidly than those of $[^3H]$-MTX-BSA and their liver concentration was significantly higher than those of other treatment (p<0.01). In addition, their uptake compared to the amount taken up by the liver (1 : 33.1 at 10 min, 1 : 24.1 at 120 min). All these suggested that MTX-LBSA conjugate is one of the drug delivery system (DDS) that is advanced in concentrating MTX in the liver and minimizing the renal toxicity of MTX.

• Journal of the Korean Chemical Society
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• v.27 no.5
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• pp.340-344
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• 1983

It has been found that both of the iridium (Ⅰ) complexes, Ir$(ClO_4$)(AN)(CO)$(Ph_3P)_2$(AN = $CH_2$CHCN, $Ph_3P = (C_6H_5)_3$P) and [Ir(AN)(CO)$(Ph_3P)_2]ClO_4$, react with $Cl^-$ to give IrCl(AN)(CO)$(Ph_3P)_2$, and [Ir(AN)(CO)$(Ph_3P)_2]ClO_4$ dissociates AN to yield Ir$(ClO_4)(CO)(Ph_3P)_2$ in the absence of excess AN added, and Ir$(ClO_4)(CO)(Ph_3P)_2$ reacts with $Cl^-$ to produce IrCl(CO)$(Ph_3P)_2$. It is suggested that the catalytic polymerization of AN with Ir$(ClO_4)(AN)(CO)(Ph_3P)_2$ proceeds through the formation of [(CO)(Ph_3P)_2$Ir(-CH=CHCN)(H)($CH_2$=CHCN)]Cl$O_4$ followed by the formation of iridium(alkyl)(alkenyl) type complex which undergoes a reductive elimination to produce the polymer of acrylonitrile.

• Journal of the Korean Chemical Society
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• v.53 no.5
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• pp.530-535
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• 2009

Dicyclohexyl telluride was obtained in a high yield by the reaction of cyclohexyl bromide with NaTeH(prepared in situ) in an aqueous ethanolic solution. A series of new organotelluronium salts of the general formula ${(cyclo-C_6H_11)}_2Te(R)X$ (where R = $CH_3$, X = I (1); R = $C_2H_5$, X = Br(2); R = $C_2H_5$, X = I (3); R = C_3H_5$, X = Br (4)) were prepared by the reaction of ${(cyclo-C_6H_11)}_2Te$ with the corresponding alkyl halide. Reaction of 1 with NaBPh4 gave compound 5 ( i.e. R = CH3, X = BPh4 ‒) in 78% yield. Reaction of ${(cyclo-C_6H_11)}_2Te$ with benzyl bromide and 4-bromophenacyl bromide gave unexpectedly dibenzylcyclohexyltelluronium bromide (6) and bis(4-bromophenacyl)cyclohexyltelluronium bromide (7), respectively. Reaction of 6 with NaBPh4 gave the corresponding tetraphenylborate derivative (8) in high yield. $^1H$ NMR studies revealed that in $CDCl_3$solution compound 1 eliminated alkyl halide. Conductivity, IR, $^1H\;and\;^{13}C$ NMR and thermal data for the new compounds are presented and discussed.