• Title/Summary/Keyword: Intermediate complex

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Vertically Partitioned Block Nested Loop join on Set-Valued Attributes (집합 값을 갖는 애트리뷰트에 대한 수직적으로 분할된 블록 중첩 루프 조인)

  • Whang, Whan-Kyu
    • Journal of Industrial Technology
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    • v.28 no.B
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    • pp.209-214
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    • 2008
  • Set-valued attributes appear in many applications to model complex objects occurring in the real world. One of the most important operations on set-valued attributes is the set join, because it provides a various method to express complex queries. Currently proposed set join algorithms are based on block nested loop join in which inverted files are partitioned horizontally into blocks. Evaluating these joins are expensive because they generate intermediate partial results severely and finally obtain the final results after merging partial results. In this paper, we present an efficient processing of set join algorithm. We propose a new set join algorithm that vertically partitions inverted files into blocks, where each block fits in memory, and performs block nested loop join without producing intermediate results. Our experiments show that the vertical bitmap nested set join algorithm outperforms previously proposed set join algorithms.

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Sandwich Intermediate Sitting-atop Complexation between Free Base meso-tetraarylporphyrins and Tellurium(IV) chloride

  • Dehghani, Hossein;Bakhshayesh, Sara;Shaterian, Maryam;Motamedi, Leila
    • Bulletin of the Korean Chemical Society
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    • v.31 no.4
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    • pp.815-818
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    • 2010
  • Free base meso-tetraarylporphyrins ($H_2T(X)PP$) react with tellurium(IV) chloride ($TeCl_4$) in mild conditions for formation sandwich intermediate sitting-atop (i-SAT) complexes, [$TeCl_4(H_2T(X)PP)_2$]. $^1H$ NMR, $^{13}C$ NMR, UV-vis, FT-IR and elemental analysis were used for characterization of the products. In the proposed structure of the i-SAT complexes, four pyrroles of each porphyrin ring are tilted alternatively up and down and this appropriates suitable orientation of lone pairs of two pyrrolenine nitrogens for electron donation to a tellurium center. $^1H$ NMR and FT-IR results showed that in the produced complex, hydrogen atoms of porphyrin macrocycles remained on the pyrrole nitrogens.

Mechanism of Peroxide-supported Hydroxylation by Cytochrome P-450 : Its Formation Pattern of the Active Intermediate (Hydroperoxide 의존성 반응에서의 Cytochrome P-450의 산화활성종 형성양식)

  • 문전옥;김기헌
    • YAKHAK HOEJI
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    • v.37 no.1
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    • pp.95-99
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    • 1993
  • Peroxidase activity of cytochrome P-450 was examined using N, N-dimethylaniline (NDA) as a substrate and cumene hydroperoxide (CHP) as an oxidant. The initial rates of the N-demethylation for varied concentrations of NDA (0.05-0.5 mM) by P-450 at different fixed concentrations of CHP (0.02-0.2 mM) were determined. The results suggest that P-450 proceeds its peroxidative reaction by the rapid equilibrium random bi bi mechanism to form a ternary complex with substrate and oxidant as an active intermediate.

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Vascularized Osteocutaneous Fibular free Flap for Reconstruction of Mid Foot

  • Chung, Yoon-Kyu;Hong, Joon Pio;Kim, Sug-Won
    • Archives of Reconstructive Microsurgery
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    • v.9 no.1
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    • pp.75-79
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    • 2000
  • The foot plays a vital role in standing and gait. This function results from harmonious interaction of bones, joints, and soft tissue. An imbalance or a defect in such structures can lead to impaired function of the foot. The mid foot, composed of cunieforms, navicular and cuboid bone, plays a vital role in maintaining longitudinal and transverse arches and injury or defects to this region can cause instability of the foot. This paper reports a case of complex foot injury; soft tissue defect of dorsum of foot, and medial and intermediate cuneiform bone defect, reconstructed in a single stage using vascularized osteocutaneous fibular free flap. Segmented to fit the defects of medial and intermediate cuneiform bones and a skin paddle providing adequate coverage, restored the stability to the arches and function of the midfoot. The fibula osteocutaneous free flap has appealing characteristics for reconstruction of the foot and the complex mid foot injuries can be considered to the long list of indications.

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Synthesis and Reactivity of a Mononuclear Manganese(II) Complex Having Pseudo-Seven Coordination Environment

  • Yoon, Jee-Hee;Seo, Mi-Sook;Kim, Young-Mee;Kim, Sung-Jin;Yoon, Sung-Ho;Jang, Ho G.;Nam, Won-Woo
    • Bulletin of the Korean Chemical Society
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    • v.30 no.3
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    • pp.679-682
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    • 2009
  • Utilizing a planar five coordinating N3S2 ligand, 2,6-bis(2-methylthiophenyliminomethyl)pyridine, a pseudo 7-coordinated manganese(II) complex with two labile triflate anions in the axial positions was synthesized. The reaction of the manganese(II) complex with an oxidant, iodosylbenzene, produced a metastable high-valent manganese(IV)-oxo species at 0 ${^{\circ}C}$. The high-valent Mn(IV)-oxo intermediate was characterized with a UV-vis spectrophotometer and an electrospray ionization mass spectroscopy. Reactivity studies of the Mn(IV)=O species revealed that the intermediate is capable of oxygenating $PPh_3$ and N-dealkylating N,N-dimethyl-toludine.

Automatic Process Design System for Cold Forging of Fasteners with Various Head Geometries (다양한 머리 형상을 갖는 체결구의 냉간 단조 자동 공정 설계 시스템)

  • 김홍석;임용택
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 1994.10a
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    • pp.141-148
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    • 1994
  • In order to improve the productivity of cold forging at low production cost, an integrated system's approach is necessary in handling the material preparation and the optimum process design, considering the forming machines, tooling, and operation including quality control. As the first step toward this approach, an expert system for multi-stage cold forging process design for fasteners with various head geometries is developed using Prolog language on IBM 486 PC. For effective representation of the complex part geometries, the system uses the multiple element input, and the forward inference scheme in determination of the initial billet size and intermediate forging steps. In order to determine intermediate steps, the basic empirical rules for extrusion, heading, and trimming were applied. The required forming loads and global strain distributions at each forging step were calculated and displayed on the PC monitor. The designed process sequence drawing can be obtained by AutoCAD. The developed system will be useful in reducing trial and error of design engineers in determining the diameter and height of the initial cylindrical billet from the final product geometry and the intermediate necessary sequences.

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Synthesis and optical properties of ZnO thin films prepared by SILAR method with ethylene glycol

  • Lee, Pay-Yu;Chang, Sheng-Po;Chang, Shoou-Jinn
    • Advances in nano research
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    • v.1 no.2
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    • pp.93-103
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    • 2013
  • An ultrasonic-mediated assisted stepwise method has been developed for depositing transparent ZnO films from aqueous solution. Rinsing in low ethylene glycol temperature was easy to produce intermediate phase of $Zn(OH)_2$, rinsing in $120^{\circ}C$ ethylene glycol was observed the diffraction peak of intermediate $Zn(OH)_2$ in early report, the rinsing temperature plays an important role in the process of $Zn(OH)_2$ phase transformed to ZnO, high rinsing temperature actually improved the intermediate phase. However, the effect of rinsing on the intermediate phase is yet to be understood clearly. The effect of different rinsing procedures, involving either of or a combination of successive ionic layer adsorption and reaction (SILAR) and ultrasonic-assisted rinsing, prior to hydrolysis in ethylene glycol was found to improve the occurrence $Zn(OH)_2$ in ZnO thin films. In the zinc complex ($[Zn(NH_3)_4]^{2+}$) solution, excess ($[Zn(NH_3)_4]^{2+}$) absorbed in glass substrate transformed incompletely to ZnO and exist as $Zn(OH)_2$ phase in thin films. In films deposited at low temperature, rinsing procedure is applied to improve excess $Zn(OH)_2$ and obtain smoother transparent thin films.

Dehydropolycondensation of Aminophenols under the Catalytic Acition of Metallic Chelate Compounds (Ⅲ) Reactions of the Isomers, Reaction Mechanisms, and the Structures of the Oligomers (金屬킬레이트 化合物의 觸媒作用에 依한 Aminophenol 類의 酸化的 重縮合反應 (Ⅲ) 異性體의 反應, 反應機構 및 生成物의 構造)

  • Choi, Kyu-Suck
    • Journal of the Korean Chemical Society
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    • v.12 no.3
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    • pp.128-137
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    • 1968
  • In the oligomerization of p-aminophenol by the catalytic action of Fe-EDTA complex in the aqueous medium, the mixed complex intermediate, Fe-EDTA-M type, is considered to be formed, from which active radicals of the monomer are produced. In this system, polymerization is presumed to proceed as follows: Free radical formation ${\to}$ Coupling ${\to}$ Activation ${\to}$ Coupling, and so on. In this study, the form of the monomer and coordination state in the mixed complex, the catalytic action of Fe-EDTA the complex, the reaction mechanism, and the structure of the oligomers are discussed.

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Calculation of Degenerated Eigenmodes with Modified Power Method

  • Zhang, Peng;Lee, Hyunsuk;Lee, Deokjung
    • Nuclear Engineering and Technology
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    • v.49 no.1
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    • pp.17-28
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    • 2017
  • The modified power method has been studied by many researchers to calculate the higher eigenmodes and accelerate the convergence of the fundamental mode. Its application to multidimensional problems may be unstable due to degenerated or near-degenerated eigenmodes. Complex eigenmode solutions are occasionally encountered in such cases, and the shapes of the corresponding eigenvectors may change during the simulation. These issues must be addressed for the successful implementation of the modified power method. Complex components are examined and an approximation method to eliminate the usage of the complex numbers is provided. A technique to fix the eigenvector shapes is also provided. The performance of the methods for dealing with those aforementioned problems is demonstrated with two dimensional one group and three dimensional one group homogeneous diffusion problems.