• Bulletin of the Korean Chemical Society
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• 제31권12호
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• pp.3707-3710
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• 2010

A chromo/fluorogenic $NO_2S_2$-macrocycle L functionalized with nitrobenzofurazan unit as a dual-signaling probe was synthesized and structurally characterized by single crystal X-ray analysis. In a cation-induced color change experiment, L exhibited excellent $Hg^{2+}$ ion selectivity by showing the color change from orange-red to yellow. However, this hypochromic shift by $Hg^{2+}$ was observed for the weaker coordinating anion system such as ${NO_3}^-$ and ${ClO_4}^-$ ions. The observed anion effect is due to the strong coordination of anions inhibits the bond formation between $Hg^{2+}$ and the macrocyclic tert-N atom, which is sensitive to induce the color change. In the fluorometric experiment, L showed chelate-enhanced fluorescence change effect only with $Hg^{2+}$ ion, together with a change from yellow to green emission. The sensing ability for $Hg^{2+}$ with the proposed chemosensor L is due to the stable complexation with 1:1 stoichiometry (metal-to-ligand).

• Bulletin of the Korean Chemical Society
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• 제34권2호
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• pp.374-378
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• 2013

Two novel binuclear metal-organic coordination complexes [$Cd_2(Hdpa)_4(bpy)_2$] (1), [$Dy_2(dpa)_2(bpy)_2(NO_3)_2-(H_2O)_2$](bpy) (2) (where $H_2dpa$ = biphenyl-2,2'-dicarboxylic acid, bpy = 2,2'-bipyridine) have been synthesized under hydrothermal conditions and characterized by single crystal X-ray diffraction, spectral method (IR), elemental analysis (EA), powder X-ray diffraction (XRD), electronic spectra (UV-vis), fluorescent in the solid state and thermogravimetric analysis (TGA). Complexes 1-2 crystallizes isomorphously in the Triclinic space group P-1. The ${\pi}-{\pi}$ stacking interactions and hydrogen-bonds play a vital role in determining the crystal packing and construction of the extended 3-D supramolecular network.

• 한국산업융합학회 논문집
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• 제9권2호
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• pp.141-145
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• 2006

In case of sense case manufactured by method of outage capacity, sensitivity is declined by outside effect and method of the photo electricity has a problem in transmission. therefore, packing case of composite sense should be developed to improve such a problem about influence of outside environment and its property evaluation has been performed. Mechanical property and result of analysis & test evaluation of Mat'l on aluminum die-casting(ADC 12type) Mat'l developed are as following. Tensile test piece, No. 4 of KS B 0801, has been applied to mechanical property test of Mat'l and It has been tested by method of metal mat'l tensile test(KS B 0802 : 2003). It can be found that physical property to KS(Korea Standard) is excellent. and homogeneous mechanical property appears. Test of Mat'l analysis has been performed by using OE Spectrometer, according to ASTM E 1251 : 1994 regulation. Consequently, good and homogeneous component contents classified by element to standard, except for Fe, have been obtained with coordination of Fe content as below 1.3% from composition standard of Aluminum Die-casting.

• Bulletin of the Korean Chemical Society
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• 제21권8호
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• pp.779-784
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• 2000

Comparing the adsorption properties and dissociation on a Pt(111) iththat ona Fe(111) surface, we have con-sidered seven coordination modes of the adsorbed binding site: $di-${\sigma}$${\Delta}$\mu\pi/\mu$, 1-fbld,2-fold, and 3-fbld sites. On the Pt(111) surface, t he adsorbed binding site of carbon dioxide was strongestat the1-fold site and weakest at the $\pi/\mu-site.$ The adsorbed binding site on the Fe(111) surface was strongest at the di-бsite and weakest at the 3-fold site. We have found that the binding energy at each site that excepted 3-fold on the Fe(111) surface was stronger than the binding energy on the Pt(111) surface and that chemisorbed $CO_2bends$ because of metal mixing with $2\piu${\rightarrow}$6a_1CO_2orbital.$, The dissociation reaction occured in two steps, with an intermediate com-plex composed of atomic oxygen and ${\pi}bonding$ CO forming. The OCO angles of reaction intermediate com-plex structure for the dissociation reaction $were115^{\circ}Con$ the Pt(111), and $117^{\circ}C$ on the Fe(111) surface. We have found that the $CO_2dissociation$ rea11) surface proceeds easily,with an activationenergy about 0.2 eV lower than that on the Pt(111) surface.

• 대한화학회지
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• 제63권3호
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• pp.160-165
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• 2019

A series of reactions between an amino alcoholic ligand, cis-2-((2-((2-hydroxyethyl)amino)ethyl)amino)cyclohexan-1-ol (HEAC), with the mixtures of group 12 metals including, $HgCl_2/CdCl_2$, $HgCl_2/CdI_2$, $ZnCl_2/CdCl_2$ and $ZnCl_2/CdCl_2/HgCl_2$ was experimentally and theoretically studied to determine the most stable product of these reactions. Furthermore, the Cambridge Structural Database (CSD) studies were done to evaluate the theoretical results. The products were characterized by elemental analysis, FT-IR, Raman, $^1H$ NMR spectroscopy and single-crystal X-ray diffraction. Based on these investigations a binuclear structure of cadmium, [$Cd_2(HEAC)_2({\mu}-Cl)_2Cl_2$] (1), is the most stable product that was formed in all studied reactions between HEAC and metals mixtures. In this structure, the cadmium atom has a $CdN_2O({\mu}-Cl)_2Cl$ environment and distorted octahedral geometry.

• Bulletin of the Korean Chemical Society
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• 제9권5호
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• pp.303-308
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• 1988

Four crystal structures of dehydrated Ag(I) and Tl(I) exchanged zeolite A, $Ag_{12-x}Tl_x$-A, x = 2, 3, 4, and 5, have been determined by single-crystal x-ray diffraction techniques. Their structures were solved and refined in the cubic space group Pm3m at $21(1)^{\circ}C$. All crystals were ion exchanged in flowing streams of mixed $AgNO_3\;and\;TlNO_3$ aqueous solution, followed by dehydration at $350^{\circ}C$ and $2{\times}10^{-6}$ Torr for 2 days. In all of these structures, one-sixth of the sodalite units contain octahedral hexasilver clusters at their centers and eight $Ag^+$ ions are found on threefold axes, each nearly at the center of a 6-oxygen ring. The hexasilver cluster is stabilized by coordination to eight $Ag^+$ ions. The Ag-Ag distance in the cluster, ca. 2.92 ${\AA}$, is near the 2.89 ${\AA}$ bond length in silver metal. The remaining five-sixths of the sodalite units are empty of silver species. The first three $Tl^+$ ions per unit cell preferentially associate with 8-oxygen rings, and additional $Tl^+$ ions, if present, are found on threefold axes in the large cavity.

• 한국의류산업학회지
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• 제9권6호
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• pp.663-670
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• 2007

Arts is the expression of reasoning and conscious life of human and arouse human the concept of existence, utmost emotion and excellent thoughts. Also it makes humans life very abundant. I make it come first to get rid of the art thirst on the opposite sight of technical one for hair as on part of humans body. Next purpose is that to confirm the esthetic value of 'hair arts' by solidify the academic ground of beauty arts through creating 'hair arts' works and learning and make the direction for the beauty industry and education of the next generation. In this study I investigated the Greek myth and the hair styles of ancient Greek Goddesses. On the basis of that symbols I elaborated hair formative works made of metal and studied, analyzed and displayed that. Work No.1 'aphne' pictures the second of changing into a laurel tree avoiding the love. Secondly 'Muse Erato' was exhibited the peaceful figure that have enough the fine melodies. 'Leda' brings out the feature of Leda resembling a swan and the fourth piece, 'Eos' conveys the brilliant and mystery of dawn. So this study conducted based on the concept of practical hair and have made efforts to be close to theoretical manufacturing research needed at making hair arts works and academic one needed at organic design composition for pioneering new field, 'art hair.' I hope these 'hair arts' works make creativity of the practise hair alive. It will be very thankful to me if this study can help even though slightly for splendid beauty arts to make its status firm as a one part of arts, and there are following studies.

• 대한화학회지
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• 제38권11호
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• pp.833-840
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• 1994

8-Quinolinecarboxaldehyde (1)와 1,5-hexadiene (2)을 월킨슨 촉매(3)와 $AgBF_4(8)$의 혼합 촉매에서 반응시키면 8-quinolinyl 5-hexenyl ketone(4)와 8-quinolinyl 5-hexen-2-yl ketone (9)이 높은 수율로 반응초기에 생성된다. 가지달린 alkenyl 케톤인 9가 생성되는 이유는 월킨슨 촉매와 $AgBF_4(8)$의 반응에서 촉매에 빈 배위공간이 만들어져 1,5-hexadiene의 하이드로메탈레이션반응에서 $AgBF_4(8)$를 넣지 않았을 때보다는 입체장애가 적은 5.5각형의 중간체를 만들 수 있기 때문으로 설명된다. $AgBF_4(8)$의 사용량이 많으면 많을수록 9가 4보다 많은 비율로 생성되며, 장시간과 고온에서는 생성된 9와 4의 혼합물이 10과 5의 내부올레핀을 함유한 alkenyl 케톤으로 이성질화반응이 진행됨을 관찰할 수 있었다. 특히 고온으로 반응을 진행시킬수록 8-quinolinyl cyclopentylmethyl ketone (11)의 생성이 눈에 띄게 높아짐을 알 수 있었다.

• Journal of Microbiology and Biotechnology
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• 제30권8호
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• pp.1261-1271
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• 2020

Cytochrome c_L (Cytc_L) is an essential protein in the process of methanol oxidation in methylotrophs. It receives an electron from the pyrroloquinoline quinone (PQQ) cofactor of methanol dehydrogenase (MDH) to produce formaldehyde. The direct electron transfer mechanism between Cytc_L and MDH remains unknown due to the lack of structural information. To help gain a better understanding of the mechanism, we determined the first crystal structure of heme c containing Cytc_L from the aquatic methylotrophic bacterium Methylophaga aminisulfidivorans MP^T at 2.13 Å resolution. The crystal structure of Ma-Cytc_L revealed its unique features compared to those of the terrestrial homologues. Apart from Fe in heme, three additional metal ion binding sites for Na⁺, Ca⁺, and Fe²⁺ were found, wherein the ions mostly formed coordination bonds with the amino acid residues on the loop (G93-Y111) that interacts with heme. Therefore, these ions seemed to enhance the stability of heme insertion by increasing the loop's steadiness. The basic N-terminal end, together with helix α4 and loop (G126 to Y136), contributed positive charge to the region. In contrast, the acidic C-terminal end provided a negatively charged surface, yielding several electrostatic contact points with partner proteins for electron transfer. These exceptional features of Ma-Cytc_L, along with the structural information of MDH, led us to hypothesize the need for an adapter protein bridging MDH to Cytc_L within appropriate proximity for electron transfer. With this knowledge in mind, the methanol oxidation complex reconstitution in vitro could be utilized to produce metabolic intermediates at the industry level.

• Bulletin of the Korean Chemical Society
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• 제25권5호
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• pp.676-680
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• 2004

Complexes M($C_7H_2NO_5)3H_2O{\cdot}H_2O{\cdot}0.25MeCN$ (M=Ni, Co) were crystallized from the reactions of $Ni(CH_3COO)_2{\cdot}4H_2O\;or\;Co(CH_3COO)_2{\cdot}2H_2O$ with KSCN and 2,6-dicarboxy-4-hydroxypyridine (chelidamic acid). The structures were characterized by X-ray crystallography. The crystal structures of 1 and 2 show a distorted octahedral coordination geometry around the M(II) ions, which are chelated by one nitrogen atom and two oxygen atoms of the chelidamic acid and three water molecules. Complexes 1 and 2 display the hydrogen-bonded 3D framework. The magnetic behavior of 2 exhibits antiferromagnetic interaction.