• Title/Summary/Keyword: Structure refinement

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Preparation and Structure of $[Ni(L)]I_2$ (L:3,5,10,12-Tetramethyl-1,4,8,11-tetraazacyclotetradecane) ($[Ni(L)]I_2$ (L:3,5,10,12-Tetramethyl-1,4,8,11-tetraazacyclo-tetradecane) 합작물의 합성 및 구조)

  • 최기영;김동원
    • Korean Journal of Crystallography
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    • v.8 no.2
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    • pp.119-123
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    • 1997
  • The complex [Ni(L)]I2 (1) (L:3,5,10,12-Tetramethly-1,4,8,11-tetraazacyclotetradecane) has been prepared and characterized by X-ray diffraction methods. The complex 1 crystallized in the orthorhombic system, space group Pcab with cell parameters a=13.293(1) Å, b=28.550(7) Å, c=10.804(1) Å, z=8. Least-squares refinement of 1 led to a R(Rw) factor of 0.043 (0.046) for 1851 observed reflections of Fo>3o (Fo). The crystal structure of 1 has a slightly distorted square-planar geometry and adopts the trans-III conformation.

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Two-dimensional nonconforming finite elements: A state-of-the-art

  • Choi, Chang-Koon;Kim, Sun-Hoon;Park, Young-Myung;Chung, Keun-Young
    • Structural Engineering and Mechanics
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    • v.6 no.1
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    • pp.41-61
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    • 1998
  • A state-of-the-art report on the new finite elements formulated by the addition of nonconforming displacement modes has been presented. The development of a series improved nonconforming finite elements for the analysis of plate and shell structures is described in the first part of this paper. These new plate and shell finite elements are established by the combined use of different improvement schemes such as; the addition of nonconforming modes, the reduced (or selective) integration, and the construction of the substitute shear strain fields. The improvement achieved may be attributable to the fact that the merits of these improvement techniques are merged into the formation of the new elements in a complementary manner. It is shown that the results obtained by the new elements give significantly improved solutions without any serious defects such as; the shear locking, spurious zero energy mode for the linear as well as nonlinear benchmark problems. Recent developments in the transition elements that have a variable number of mid-side nodes and can be effectively used in the adaptive mesh refinement are presented in the second part. Finally, the nonconforming transition flat shell elements with drilling degrees of freedom are also presented.

Synthesis and Structure of [Cu(L)](ClO4)2 (L;3,5,10,12-Tetramethyl-1,4,8,11-tetraazacyclotetradecane) ([Cu(L)](ClO4)2 (L:3,5,10-12-Tetramethyl-1,4,8,11-tetraazacyclotetradecane) 착물의 합성 및 구조)

  • 최기영;홍청표
    • Korean Journal of Crystallography
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    • v.9 no.1
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    • pp.6-10
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    • 1998
  • The complex[Cu(L)](ClO4)2 (1) (L:3,5,10,12-Tetramethyl-1,4,8,11-tetraazacyclotetradecane) has been synthesized and structurally characterized. The complex 1 crystallizes in the monoclinic system, space group P21/n with cell parameters a=8.208(2)Å, b=13.339(6) Å, c=10.752(5) Å, β=111.02(4)˚ Z=2. Least-squares refinement of 1 led to a R(RW)factor of 0.073 (0.142) for 617 observed reflections of F0>40(F0). The crystal structure of 1 has a square-planar geometry and adopts the trans-III conformation.

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Crystal Structure of Macrocyclic Tetraamine Thiocyanate Copper(II) Complex (거대고리 Tetraamine Thiocyanate Copper(II) 착물의 결정구조)

  • Choe, Gi-Yeong;Kim, Chang-Seok;Seo, Il-Hwan
    • Korean Journal of Crystallography
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    • v.9 no.1
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    • pp.11-14
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    • 1998
  • The synthesis and characterization of [Cu(L)](NCS)2 (1) (L:2,5,9,12-Tetramethyl-1,4,8,11-tetraazacyclotetradecane) are described. Crystal structure of 1 crystallizes in the monoclinic system, space group P21/a, a=7.622(2)Å, b=17.645(2) Å, c=8.223(3) Å, β=109.99(2)˚ Z=2. Least-squares refinement of 1 led to a R(Rw) factor of 0.087 (0.158) for 1535 observed reflections of F0>40(F0). The complex 1 has a square planar geometry with average Cu-N (secondary amines) bond distance of 2.030(4)Å. The axially disposed thiocyanate anions are not coordinated with Cu-N distances of 2.842(7) Å.

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Preparation and Structure of $Re(≡NC_6H_5)(DPPE)CI_3$, $[DPPE=Ph_2PCH_2CH_2PPh_2]$ ($Re(≡NC_6H_5)(DPPE)CI_3$화합물의 합성 및 구조)

  • 박병규;정건수
    • Korean Journal of Crystallography
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    • v.6 no.2
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    • pp.93-97
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    • 1995
  • Re(≡NC6H5)(PPh3)2CI3, I, reacted with, 1,2-bis(diphenylphosphino)ethane (DPPE) to give fac-Re(≡NC6H5)(DPPE)CI3, II. The product has been characterized by 1H-NMR, elemental analysis, and X-ray crystallography. II Crystalizes in the monoclinic space group Pc, with cell parameters a=11.083(3)Å, b=10.930(1)Å, c=14.081(2)Å, β=108.37(2)°, Z=2. Least-squares refinement of the structure led to a R(wR2)factor of 0.0254(0.0607) for 2888 unique reflections of I>2σ(I) and for 352 variables.

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Preparation and Structure of $Re(NC_6F_5)(PPh_3)_2Cl_3 $ ($Re(NC_6F_5)(PPh_3)_2Cl_3 $화합물의 합성 및 구조)

  • 박병규;김영웅
    • Korean Journal of Crystallography
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    • v.7 no.2
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    • pp.113-119
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    • 1996
  • Reaction of Re(O)(PPh3)2Cl3,I, with 2,3,4,5,6-pentafluoroaniline (C6F5NH2), produced Re(NC6F5)(PPh3)2Cl3, II. The product has been characterized by 1H-NMR, elemental analysis, and X-ray diffraction. II crystallizes in the orthorhombic system, space group Pna21 with cell parameters a=18.763Å, b=14.737(2)Å, c=16.707(3)Å, Z=4. Least-square refinement of the structure led to an R(wR2)factor of 0.0455(0.1148) for 3319 unique reflections of I > 2σ(I) and for 174 variables.

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Ultra-fine Grained Aluminum Alloy Sheets fabricated by Roll Bonding Process

  • Kim, Hyeong-Uk;Tsuji, Nobuhiro
    • Proceedings of the Materials Research Society of Korea Conference
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    • 2009.05a
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    • pp.6.2-6.2
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    • 2009
  • Ultra-fine grained (UFG) Al alloys, which have submicron grain structures, are expected to show outstanding high strength at ambient temperature and excellent superplastic deformation at elevated temperatures and high strain rate. In order to get the UFG microstructure, various kind of severe plastic deformation (SPD) processes have been developed. Among these processes, accumulative roll bonding (ARB) process is a promising process to make bulky Al sheets with ultrafine grained structure continuously. The purpose of the present study is to clarify the grain refinement mechanism during the ARB process and to investigate on the effects of ultra-fine grained structure on the mechanical properties. In addition, UFG AA8011 alloy (Al-0.72wt%Fe-0.63wt%Si) manufactured by the ARB had fairly large tensile elongation, keeping on the strength. In order to clarify the reason for the increase of elongation in the UFG AA8011 alloy, detailed microstructural and crystallographic analysis was performed by TEM/Kikuchi-line and SEM/EBSP method. The unique tensile properties of the UFG AA8011 alloy could be explained by enhanced dynamic recovery at ambient temperature, owing to the large number of high angle boundaries and the Al matrix with high purity.

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The Improvement for Licensing Policy to Promote R&D Outputs of National R&D Programs in Korea (국가연구개발사업 기술료 제도의 개선방안 연구)

  • Do, Kye-Hoon;Um, Ik-Cheon
    • Journal of Korea Technology Innovation Society
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    • v.14 no.2
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    • pp.260-278
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    • 2011
  • Along with the launch of National R&D Program in 1982, National R&D licensing policy began to operate in order to expand and promote the outputs of R&D. Even though various studies attempted to draw plans to improve the National R&D licensing policy, most of their focus was limited to the collection and allocation structure of royalty. Thus, with the aim of approaching National R&D licensing policy in a whole cyclic perspective [from collection allocation to execution' post control], this study incorporates interviews with specialists and officials in charge of technology licensing fee, Industry-University-Institute surveys as well as literature review. Through this endeavor, suggestions are made in the aspects of (1) National R&D licensing policy reformation, (2) Technology licensing fee collection and allocation structure refinement, (3)Post control system establishment.

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A Study on Sensibility Ergonomics Approach to Bathroom Design (감성공학기법을 적용한 욕실디자인에 관한 연구)

  • Lee, Han-Seok;Jung, Hyun-Won;Oh, Young-Keun;Jung, A-Young;Kim, Jung-Wook
    • Korean Institute of Interior Design Journal
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    • v.18 no.6
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    • pp.69-76
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    • 2009
  • As sensibility ergonomics are broadly spread, recently in interior design area, interests on roles of sensibility, sensibility effects for users, and etc has been increased. As a study on sensibility design for interior design area, the study applied sensibility ergonomics technique to bathroom interior design. Sensibility ergonomics technique is integrated into each phase of bathroom design process in order to produce 4 design alternatives. Sensibility evaluation on design alternatives was performed for subject of designers, and analyzed the results to show the relationship between sensibility of designers and design factors and to identify characteristics of designer's sensibility structure. The results of the study are as follows. First, it's found that in the bathroom interior design of sustainable concept, uses of bright colors with white tone and floor tile creates positive sensibility responses such as delight, healthiness, spaciousness, and cheerfulness. Second, designers' sensibility structure about sustainable bathroom is composed of three axles, healthiness, eco-friendliness, and refinement. Third, designers think colors of interior and finished materials is most important, and window, artificial lighting, layout, and space size related to those is important too. The process and approach in the study might contribute to building a fundamental of sensibility design research in interior design area.

Synthesis and Characterization of 1,4-Diimine Complexes of 1,2,3,4,5-Pentamethylcyclopentadienylrhodium and iridium

  • Paek, Cheol-Ki;Ko, Jae-Jung;Uhm, Jae-Kook
    • Bulletin of the Korean Chemical Society
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    • v.15 no.11
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    • pp.980-984
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    • 1994
  • Monomeric rhodium and iridium diimine complexes $Cp^*M(HNRNH)(Cp^*$ = 1,2,3,4,5-pentamethylcyclopentadienyl : (M=lr; R=o-$C_6H_4 (1a), 4,5-(CH_3)_2-C_6H_2-1,2 (1b), 4,5-(Cl)_2-C_6H_2-1,2$ (1c), NCC=CCN-1,2 (1d): M=Rh; R=NCC=CCN-1,2 (1e)) have been synthesized from $[CP^*MCl_2]_2$ and 2 equiv. of diamine in the presence of $NEt_3$. The Crystal structure of 1a was determined by X-ray diffraction method : 1a was crystallized in the monoclinic system, space group $P2_{1/c}$, with lattice constants a=9.543 (1) ${\AA}$, b=16.286 (1) ${\AA}$, c=10.068 (1) ${\AA}$ and ${\beta}$=99.25 (1), with Z= 4. Least-squares refinement of the structure led to R factor of 0.049. The coordination sphere of rhodium and iridium can be described as a 2-legged piano-stool. All complexes are highly colored. Electrochemical studies show that 1d and 1e display quasi-reversible reduction and 1a-1c display irreversible reductions, suggesting that the acceptor orbital might be localized on the diimine ring.