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Self-cleaning Properties of TiO2-SiO2-In2O3 Nanocomposite Thin Film

  • Eshaghi, Akbar;Eshaghi, Ameneh
    • Bulletin of the Korean Chemical Society
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    • 제32권11호
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    • pp.3991-3995
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    • 2011
  • $TiO_2-SiO_2-In_2O_3$ nanocomposite thin film was deposited on the glass substrates using a dip coating technique. The morphology, surface composition, surface hydroxyl groups, photocatalytic activity and hydrophilic properties of the thin film were investigated by AFM, XPS, methyl orange decoloring rate and water contact angle measurements. The hydroxyl content for $TiO_2$, $TiO_2-SiO_2$ and $TiO_2-SiO_2-In_2O_3$ nanocomposite films was calculated to be 11.6, 17.1 and 20.7%, respectively. $TiO_2-SiO_2-In_2O_3$ film turned superhydrophilic after 180-min irradiation with respect to pure $TiO_2$ and $TiO_2-SiO_2$ thin films. The photocatalytic decomposition of methyl orange for $TiO_2$, $TiO_2-SiO_2$ and $TiO_2-SiO_2-In_2O_3$ thin films was measured as 38.19, 58.71 and 68.02%, respectively. The results indicated that $SiO_2$ and $In_2O_3$ had a significant effect on the hydrophilic, photocatalytic and self-cleaning properties of $TiO_2$ thin film.

Al2O3-ZrO2-SiO2-R2O와 Al2O3-ZrO2-SiO2-La2O3-R2O계 유리와 부분안정화 지르코니아간의 접합거동 (Joining Behavior of YSZ Ceramics to Al2O3-ZrO2-SiO2-R2O and Al2O2-ZrO2-SiO2-La2O3-R2O Glass Systems)

  • 최진삼;배원태
    • 한국세라믹학회지
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    • 제52권1호
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    • pp.19-22
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    • 2015
  • The joining behavior of YSZ ceramics to the glasses used in the $9Al_2O_3-24ZrO_2-51SiO_2-16R_2O$ and $9Al_2O_3-24ZrO_2-51SiO_2-7La_2O_3-9R_2O$ (wt%) glass systems was investigated. The glass transition and softening temperatures were determined to be $430^{\circ}C$ and $760^{\circ}C$, respectively. The behavior of the contact angle was inversely proportional to an increase in the temperature. The Zr element in YSZ acted as a nucleation agent and contributed to the bonding behavior at the interface.

Polyoxometalate Tri-supported Transition Metal Complexes를 이용한 Dihydropyrimidinones의 one-pot 합성 (One-pot Synthesis of Dihydropyrimidinones Using Polyoxometalate Tri-supported Transition Metal Complexes)

  • Fazaeli, Razieh;Aliyan, Hamid;Mohammadifar, Foroogh;Zamani, Amir Abbas;Bagi, Mohammad Javad
    • 대한화학회지
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    • 제55권4호
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    • pp.666-672
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    • 2011
  • Vanadium 치환체인 polyoxometalate 1, [Cu(2,2'-bipy)]$[Cu(2,2'-bipy)_2]_2[PMo_8V_6O_{42}]{\cdot}1.5H_2O$을 가지고 있는 inorganicorganic complex의 촉매 활성도를 Biginelli 반응에 적용하여 연구하였다. Dihydropyrimidinones를 one-pot 합성하는 반응에서, $H_3PMo_{12}O_{40}$ 촉매 보다[Cu(2,2'-bipy)]$[Cu(2,2'-bipy)_2]_2[PMo_8V_6O_{42}]{\cdot}1.5H_2O$ 촉매가 더 좋은 결과를 나타내었다.

A cytotaxonomic study of Atractylodes japonica Koidz. ex Kitam. and A. macrocephala Koidz.

  • Chung, Gyu-Young;Kim, Mi-Suk
    • Plant Resources
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    • 제3권3호
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    • pp.179-183
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    • 2000
  • The present study was carried out to clarify the chromosome numbers and karyotype of Atractylodes japonica Koidz. ex Kitam. and A. macrocephala Koidz.. The somatic chromosome numbers of two species were same; basic chromosome number x=12, and somatic chromosome numbers 2n=24. The present result of A. japonica Koidz. ex Kitam. was same to previously reports and that of A. macrocephala Koidz. was reported first in this study. Size and shape of chromosome were some different from A. japonica Koidz. ex Kitam. and A. macrocephala Koidz.. The karyotype of A. japonica Koidz. ex Kitam. was described as follows; 2n : 24 : 8L + 14M +2S : 2 $A^{sm}$ +2 $B^{m}$ +2 $C^{m}$ +2 $D^{st}$ + 2 $E^{m}$ +2 $F^{m}$ +2 $G^{m}$ +2 $H^{sm}$ + 2 $I^{m}$ + 2 $J^{m}$ + 2 $K^{m}$ + 2 $L^{m}$ . And the karyotype of A. macrocephata Koidz. was described as follows; 2n : 24 : 10L +12M +25 : 2 $A^{m}$ +2 $B^{sm}$ +2 $C^{sm}$ +2 $D^{sm}$ +2 $E^{sm}$ +2 $E^{sm}$ +2 $G^{sm}$ +2 $H^{m}$ +2 $I^{m}$ 2 $J^{m}$ +2 $K^{m}$ +2 $L^{m}$ . .

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Preparation and Characterization of Dinuclear Metal Complexes, $[(PPh_3)_2(CO)M({\mu}-E)M(CO)(PPh_3)_2](SO_3CF_3)_2$ (M = Rh, Ir; E = 1,4-Dicyanobenzene and 1,4-Dicyano-2-butene)

  • Moonsik Kim;JaeKyun Chin;Jaejung Ko
    • Bulletin of the Korean Chemical Society
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    • 제13권5호
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    • pp.556-559
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    • 1992
  • Hydrocarbon solution of $(PPh_3)_2(CO)MOSO_2CF_3$ (M= Rh, Ir) reacts rapidly with 1,4-dicyanobenzene or 1,4-dicyano-2-butene to yield dinuclear metal complexes $[(PPh_3)_2(CO)M({\mu}-dicyanobenzene)M(CO)(PPh_3)_2](SO_3CF_3)_2$ (I: M = Rh; II: M = Ir) or $[(PPh_3)_2(CO)M({\mu}-dicyano-2-benzene)M(CO)(PPh_3)_2](SO_3CF_3)_2$ (III: M = Rh; IV: M = Ir), respectively. Compounds I, II, III, and IV were characterized by $^1H$-NMR, $^{31}P$-NMR, and infrared spectrum. Dichloromethane solution of II and IV reacts with $H_2\;and\;I_2$ to yield oxidative addition complexes $[(PPh_3)_2(CO)IrX_2({\mu}-E)X_2Ir(CO)(PPh_3)_2](SO_3CF_3)_2$ (V; E = 1,4-dicyanobenzene, $X_2$ = $H_2$; VI : E = 1,4-dicyano-2-butene, $X_2$ = $H_2$; VII; E = 1,4-dicyanobenzene, $X_2$ = $I_2$). All metal complexes are bridged by the cyanide groups. Compounds Ⅴ, Ⅵ, and Ⅶ are characterized by conventional methods.

Effect of SiO2/B2O3 ratio on Li ion conductivity of a Li2O-B2O3-SiO2 glass electrolyte

  • Kim, Young Han;Yoon, Mi Young;Lee, Eun Jung;Hwang, Hae Jin
    • Journal of Ceramic Processing Research
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    • 제13권spc1호
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    • pp.37-41
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    • 2012
  • A lithium ion conducting borosilicate glass was fabricated by a conventional melt quenching technique from a mixture of Li2CO3, B2O3 and SiO2 powders. The Li ion conductivity of the lithium borosilicate glasses was evaluated in terms of the SiO2/B2O3 ratio. In the Li2O-B2O3-SiO2 ternary glass, the glass forming region decreases with an increasing Li2O content. At the same Li2O, the crystallization tendency of the glass samples increases with the SiO2/B2O3 ratio, resulting in a reduced glass forming region in the Li2O-B2O3-SiO2 ternary glass. The electrical conductivity moderately depends on the SiO2/B2O3 ratio in the Li2O-B2O3-SiO2 ternary glass. The conductivity of the glasses slightly increases with the SiO2/B2O3 ratio. The observed phenomenon can be explained by the modification of the glass structure as a function of the SiO2 content.

팔면체형 철 (Ⅱ) Vicinal-디옥심 착물의 물리적 성질 (Physical Properties of Octahedral Iron (Ⅱ) Complexes of Vicinal-Dioximes)

  • 진종식
    • 대한화학회지
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    • 제24권5호
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    • pp.380-392
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    • 1980
  • 6배위, 작은 스핀 철(Ⅱ)착화합물, [Fe$(DH)_2B_2$]과 [Fe(D$H_2$B(CO)]($(DH)_2$=$(CHDH)_2$-(bis(1,2-cyclohexadinedioximato)(bivalent anion),$(DPGH)_2$(bis(diphenylglyoximato) bivalent anion), $(F{\alpha}DH)_2(bis(furil-{\alpaha}$-dioximato) bivalent anion), B = neutral monodentate nitrogen base)을 합성하여 이들의 물리적 성질을 적도 방향의 리간드, $(DH)_2$에 관하여 조사하였다. 적외선 스펙트럼 분석결과, [Fe$(DH)_2B(CO)] 중에서 {\pi}$-전자받게 리간드인 CO의 신축진동수 크기의 순서는 $(F{\alpha}DH)_2$ > $(DPGH)_2$ > $(CHDH)_2 화합물의 순서이고 [Fe$(DH)_2(NH_3)_2$]중에서 ${\pi}$-전자받게 성질이 없는 $NH_3$의 신축진동수 크기의 순서는 그 반대인 $(CHDH)_2$ > $(DPGH)_2 > $(F{\alpha}DH)_2$ 화합물임을 관찰하였다. 이상의 결과와 철-질소(옥심) 및 철-질소(B)의 신축진동수 데이타로부터 다음을 알았다. 즉 $(CHDH)_2$중의 질소원자들은 $(DPGH)_2$$(F{\alpha}DH)_2$ 중의 질소원자들보다 염기도는 크지만 ${\pi}$-전자받게의 경향은 적다. 상기 착물들의 전자스펙트럼을 조사한 결과 $(DH)_2의 염기도가 증가함에 따라 철로부터 $(DH)_2$로 일어나는 전하이동띠의 에너지가 증가함을 알았다.

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Synthesis and Characterization of C-meso and C-racemic Isomers of a Reinforced Tetraaza Macrocycle and Their Copper(II) Complexes

  • Jeong, Gyeong Rok;Kim, Juyoung;Kang, Shin-Geol;Jeong, Jong Hwa
    • Bulletin of the Korean Chemical Society
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    • 제35권7호
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    • pp.2043-2048
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    • 2014
  • Two isomers of a new tetraaza macrotricycle 2,2,4,9,9,11-hexaazamethyl-1,5,8,12-tetraazatricyclo[$10.2.2^{5.8}$]-octadecane ($L^2$) containing additional N-$CH_2CH_2$-N linkages, C-meso-$L^2$ and C-racemic-$L^2$, have been prepared by the reaction of 1-bromo-2-chloroethane with C-meso-$L^1$ or C-racemic-$L^1$ ($L^1$ = 5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane). Both C-meso-$L^2$ and C-racemic-$L^2$ react with copper(II) ion to form $[Cu(C-meso-L^2)]^{2+}$ or $[Cu(C-racemic-L^2)]^{2+}$ in dehydrated ethanol, but do not with nickel(II) ion under similar conditions. Crystal structure of [Cu(C-racemic-$L^2$)($H_2O$)]$(ClO_4)_2$ shows that the complex has distorted square-pyramidal coordination geometry with an apically coordinated water molecule. Unexpectedly, the Cu-N distances [2.016(3)-2.030(3) ${\AA}$] of [Cu(C-racemic-$L^2$)($H_2O$)]$(ClO_4)_2$ are longer than those [1.992(3)-2.000(3) ${\AA}$] of [Cu(C-racemic-$L^1$)($H_2O$)]$(ClO_4)_2$. As a result, $[Cu(C-racemic-L^2)(H_2O)]^{2+}$ exhibits weaker ligand field strength than $[Cu(C-racemic-L^1)(H_2O)]^{2+}$. The copper(II) complexes readily react with CN- ion to yield the cyano-bridged dinuclear complex $[Cu_2(C-meso-L^2)_2CN]^{3+}$ or $[Cu_2(C-racemic-L^2)_2CN]^{3+}$. Spectra and chemical properties of $[Cu(C-meso-L^2)]^{2+}$ and $[Cu_2(C-meso-L^2)_2CN]^{3+}$ are not quite different from those of $[Cu(C-racemic-L^2)]^{2+}$ and $[Cu_2(C-racemic-L^2)_2CN]^{3+}$, respectively.

RF 마그네트론 스퍼터링 방법을 사용해 증착된 Al이 도핑 된 ZnO 박막의 H2/(Ar + H2) 가스 비율에 따른 특성 (The properties of Al-doped ZnO films deposited with RF magnetron sputtering system in various H2/(Ar + H2) gas ratios)

  • 김좌연;한정수
    • 한국결정성장학회지
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    • 제22권3호
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    • pp.122-126
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    • 2012
  • $Al_2O_3$ 2 wt%가 도핑 된 ZnO(AZO) 타겟으로RF 스퍼터링 장비를 사용하여 $H_2/(Ar+H_2)$ 가스 비율에 따른 AZO 박막을 증착 후, 이들 박막의 특성을 조사하였다. AZO 박막은 $200^{\circ}C$, $2{\times}10^{-2}$ 공정조건에서 $H_2/(Ar+H_2)$ 가스 비율을 변화시키면서 증착하였다. AZO박막증착 중 수소가스의 첨가는 박막의 특성에 영향을 미쳤다. $H_2/(Ar+H_2)$ 가스 비율이 2.5 %일 때 비 저항(${\sim}9.21{\times}10^{-4}\;{\Omega}cm$)과 전자 이동도(${\sim}17.8\;cm^2/Vs$)는 각각 최소값과 최대값을 나타내었다. $H_2/(Ar+H_2)$ 가스 비율이 2.5 % 이상일 때는 $H_2/(Ar+H_2)$ 가스 비율이 증가할수록 비저항은 점차로 증가하였고 전자 이동도는 점차적으로 감소하였다. 전자 운반자 농도는 $H_2/(Ar+H_2)$ 가스 비율이 증가함에 따라 0 %에서 7.5 %까지 점차로 증가하였다. $H_2/(Ar+H_2)$ 가스 비율에 따라 증착된 박막의 가시광선 파장 범위에서 평균 광 투과도는 90 % 이상이었고 성장방향은 [002]이었다.

rac-Me2Si(2-p-tolylindenyl)2ZrCl2 촉매를 이용한 에틸렌/1-옥텐의 공중합 특성 (Characteristics of Copolymerization of Ethylene/1-Octene with rac-Me2Si(2-p-tolylindenyl)2ZrCl2 Catalyst)

  • 안성현;박융호
    • 공업화학
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    • 제18권5호
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    • pp.516-521
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    • 2007
  • 새롭게 합성된 $rac-Me_2Si(2-p-tolylindenyl)_2ZrCl_2$ 촉매와 인디닐 리간드에 치환체가 붙어 있지 않는 상용촉매인 $rac-Me_2Si(Ind)_2ZrCl_2$ 촉매들을 조촉매인 methylaluminoxane (MMAO)를 사용하여 에틸렌/1-옥텐 공중합을 실시하였고, 반응물 내 1-옥텐의 농도를 변화시키며 얻어진 공중합체의 특성을 조사하였다. 촉매활성에 있어서 $rac-Me_2Si(2-p-tolylindenyl)_2ZrCl_2$ 촉매를 이용하여 공중합을 실시한 경우 다리구조를 가진 다른 촉매들과 달리 촉매활성이 감소하여 comonomer의 첨가에 따라 활성이 증가하는 comonomer effect는 발견되지 않았다. $^{13}C$ NMR 분석에서 공중합체에 삽입된 1-옥텐의 양은 촉매 리간드에 붙은 치환체에 의존함을 보였으며, 2-p-tolyl 치환체가 붙은 촉매로 얻어진 공중합체에서 1-옥텐 삽입량이 더 높음을 보였다. DSC, GPC 분석에서 반응물 내 1-옥텐의 농도가 증가함에 따라 공중합체의 녹는점, 결정성, 분자량이 모두 감소하였으며 $rac-Me_2Si(Ind)_2ZrCl_2$ 촉매보다 $rac-Me_2Si(2-p-tolylindenyl)_2ZrCl_2$ 촉매의 경우 녹는점, 결정성 및 분자량의 감소폭이 더 크게 나타났다.