• Title/Summary/Keyword: Cheju I

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Cr(III)-Tetraaza Macrocyclic Complexes Containing Auxiliary Ligands (Part I); Synthesis and Characterization of Cr(III)-Benzoato and Chlorobenzoato Macrocyclic Complexes

  • Byun, Jong-Chul;Kim, Goo-Cheul;Han, Chung-Hun
    • Bulletin of the Korean Chemical Society
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    • v.25 no.7
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    • pp.977-982
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    • 2004
  • The reaction of $cis-[Cr([14]-decane)(OH_2)_2]^+$ ([14]-decane = rac-5,5,7,12,12,14-hexamethyl-1,4,8,11-teraazacyclotetradecane) with auxiliary ligands {$L_a$ = benzoate(bz) or chlorobenzoate(cbz)} leads to a new compound $[Cr([14]-decane)(bz)_2]ClO_4$ or $[Cr([14]-decane)(cbz)_2]ClO_4$. These complexes have been characterized by a combination of elemental analysis, conductivity, IR and Vis spectroscopy, mass spectrometry, and X-ray crystallography. The crystal structure of $[Cr([14]-decane)(cbz)_2]^+$ was determined. The complex shows a distorted octahedral coordination environment with the macrocycle adopting a folded cis-V conformation. The angle $N_{axial}-Cr-N_{axial}$ deviates by $14.5^{\circ}$ from the ideal value of $180^{\circ}$for a perfect octahedron. The bond angle cis-O-Cr-O between the Cr(III) ion and the two carboxylate oxygen atoms of the monodentate p-chlorobenzoate ligands is close to 90$^{\circ}$. The FAB mass spectra of the $cis-[Cr([14]-decane)(La)_2]ClO_4$ display peaks due to the molecular ions $[Cr([14]-decane)(bz)_2-H]^\;,\;[Cr([14]-decane)(cbz)_2-2H]^$ at m/z 578, 646, respectively.

Adsorption and Leaching of Organophosphorus Pesticides in the Soil of Cheju Island (제주도 토양에서 유기인계 농약의 흡착 및 용탈)

  • 감상규;고병철;오윤근;이용두;김정호
    • Journal of Environmental Science International
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    • v.8 no.3
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    • pp.379-386
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    • 1999
  • The adsorption and leaching of organophosphorus pesticides (phenthoate, diazinon, methidathion) were investigated in Namwon soli(black volcanic soil), Aewol soil(very dark brown volcanic soil) and Mureung soil(dark brown nonvolcanic soil) sampled in Cheju Island. The Freundlich constant, K value, was 52.4, 31.3 and 27.7 for phenthoate, diazinon and methidathion in Namwonsoil, respectively and decreased in the order of phenthoate, diazinon and methidathion among the pesticides. The K value of phenthoate was 52.4, 15.9 and 5.9 for Namwon, Aewol and Mureung soil, respectively and was the highest for Namwon soil with very high organic matter content and cation exchange capacity(CEC). The Freundlich constant, 1/n, showed a high correlation with organic matter content, i.e., its value was less than unity for organic matter rich soil(Namwon soil) and greater than unity for organic matter poor soil(Mureung soil). Total recoveries of pesticides in soil and leachate with leaching in soil column, were in the range of about 74~86%. The leaching of pesticides was less for phenthate with high K values, and more for methidathion with low K values among the pesticides. It was slower for Namwon soil with high K values, and more for methidathion with low K values among the pesticides. It was slower for Namwon soil with high K values, and faster for Mureung soil with low K values among the soils.

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Study of Forming Analysis Auto-body Panel Using One-step Theory (One-Step 이론을 이용한 차체판넬 성형 해석에 관한 연구)

  • Ahn H.G.;KO H.H.;Lee C.H.;Ahn B.I.;Moon W.S.;Jung D.W.
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2005.06a
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    • pp.585-588
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    • 2005
  • Many process parameters have an effect on the auto-body panel forming process. A well designed blank shape causes the material to flow smoothly, reduces the punch and yields a product with uniform thickness distribution. Therefore, the determination of an initial blank shape plays the important role of saving time and cost in the auto-body panel forming process. For these reasons, some approaches to estimate the initial blank shape have been implemented, in this paper The one-step approach using a finite element inverse method will be introduced to predict the optimal forming with changing of blank pressure the developed program is applied to auto-body panel forming.

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A Study of Tool Planning for Forming Analysis in REF SILL OTR-R/L Auto-Body Panel Stamping Process (REF SILL OTR-R/L 차체판넬 스템핑 공정에서 성형해석을 통한 공법개발에 관한 연구)

  • Ko H.H.;Ahn H.G.;Lee C.H.;Ahn B.I.;Moon W.S.;Jung D.W.
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2005.06a
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    • pp.1980-1983
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    • 2005
  • The characteristic of sheet metal process is the few loss of material during process, the short processing time and the excellent price and strength. The sheet metal process with above characteristic is common used in industrial field, but in order to analysis irregular field problems the reliable and economical analysis method is demanded. Finite element method is very effective method to simulate the forming processes with good prediction of the deformation behaviour. Among Finite element method, The static-implicit finite element method is applied effectively to analyze real-size auto-body panel stamping processes, which include the forming stage. In this paper, it was focussed on the drawability factors on auto-body panel stamping by AUTOFORM with using tool planing alloy to reduce law price as well as high precision from Design Optimization of ide. According to this study, the results of simulation will give engineers good information to access the Design Optimization of die.

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A Study in the neighbouring sea variation of Cheju and Influence of China Coastal Water by Topex/Poseidon Altimeter Data and in-situ Salinity Data

  • Cho Han Keun;Yoon Hong Joo
    • Proceedings of the KSRS Conference
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    • 2004.10a
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    • pp.188-191
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    • 2004
  • Appearance and disappearance of the China Coastal Waters(CCW) in the neighbouring sea of Cheju Island was very different yearly but usually appeared strongly in summer. At this time, sea level and salinity were varied in this area by the influence of the CCW. Satellite data(T/P;Topex/Poseidon) and Salinity (NFRID;National Fisheries Research and Development Institute) were used from 1993 to 2001. We compared with TG data of NOR I and TIP data in the observed station(33 31'N, 12632'E). Coefficient of correlation was 0.6~0.8 with the exception of 1993 and 1995. And variations of salinity was higher than $32.00\%_{\circ}$ in the southwestern part of Cheju Island and the southern part of the South Sea of Korea during June-October and SLA(Sea level Anomaly) was 10-11cm. Salinity of the southeastern part was higher than those of the southwestern part and SLA was 12~13cm because of the influence of Tsushima Current.

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A Basic Study for the Improvement Project of Housing Environment in the Cheju Island Region the Era of Globalization (지방화시대에 따른 제주지역의 주환경 개선 사업에 관한 기초 연구)

  • BongAeKim
    • Journal of the Korean housing association
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    • v.6 no.2
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    • pp.69-76
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    • 1995
  • Recent opening of the era of local government and management randers study tasks concerning the improvement of the housing conditions by improving the problems in the residential conditions of the cheju Island region so as to help improve the life qualities of this legion make the area as an international resort place, and thus develop the indentify in the heat of the people in this region. The suggestions based on the study for the improvement of housing environment are summarized as follows: (1) To improve the collective housing. housing construction plan shall b made in harmony with the skylines of the Hanra mountain alongside the East-West rides across the long diameter of the oval shape of the Island, which includes 1) the construction of housing complex in harmony with and taking advantage of the natural scene of the area. and 2) the construction of variable housing readjustable in accordance with each family structure of variable housings for multi-families, which are believed not to provide quality housing conditions. Shall be entrained. (2) Encouraging the construction of detached house : 1) construction of housings in which three generations can reside together according to the traditional family structure in the region. 2) construction of the pastoral housings. 3) construction of tenement housings partitioned for each two families. 4) development of sliver town in the rural area. (3) Using the construction mateials produced in the Cheju I land will help promote the development of identity in the heart of the people in this region.

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