• The Korean Journal of Ceramics
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• 제2권1호
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• pp.48-53
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• 1996

Ion beam assisted crystallization behavior of sol-gel derived $PbTiO_3$ thin films, deposited on bare silicon(100) substrates by spin-casting method, has been investigated. Ar ion bombardment was directly conducted on the spincoated film surface with or without heating the film from room temperature to $300^{\circ}C$. Ion dose was changed from $5{\times}10^{15}$ to $7.5{\times}10^{16}$ $Ar^-/cm^2$. Formation of (110) oriented perovskite phase was obseerved with ion dose above $5{\times}10^{16}\; Ar^+/cm^2$. Crystallization of $PbTiO_3$ thin film could be enhanced with increasing the Air ion dose, or heating the substrate during ion bombardment. Crystallization of the $PbTiO_3$ films by ion bombardment was related to the local heating effect during ion bombardment.

• Journal of Electrochemical Science and Technology
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• 제10권2호
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• pp.123-130
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• 2019

We investigated the electrochemical behavior of an electrode coated with a nickel hexacyanoferrate/graphene oxide (NiPB/GO) composite to evaluate its potential use for the electrochemical separation of radioactive Cs as a promising approach for reducing secondary Cs waste after decontamination. The NiPB/GO-modified electrode showed electrochemically switched ion exchange capability with excellent selectivity for Cs over other alkali metals. Furthermore, the repetitive ion insertion and desertion test for assessing the electrode stability showed that the electrochemical ion exchange capacity of the NiPB/GO-modified electrode increased further with potential cycling in 1 M of $NaNO_3$. In particular, this electrochemical treatment enhanced Cs uptake by nearly two times compared to that of NiPB/GO and still retained the ion selectivity of NiPB, suggesting that the electrochemically treated NiPB/GO composite shows promise for nuclear wastewater treatment.

• 한국세라믹학회지
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• 제40권9호
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• pp.855-858
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• 2003

Liquid Phase Epitaxy (LPE)법으로 Yttrium Iron Garnet (YIG:Y$_3$Fe$_{5}$O$_{12}$) 단결정 후막을 성장시킬 때 PbO계 응제에서는 Pb 이온이 성장되는 결정내로 혼입되어 성장된 막의 격자상수를 증가시키고, 일축 자기이방성 상수값(Ku)을 변화시키거나 전기 전도도를 변화시킨다. 또한 광 흡수율을 증가시키는 등의 성장된 막의 물성에 악영향을 미친다. 열처리 후 Pb 이온의 휘발로 인한 결정내의 농도감소로 성장된 단결정 후막의 격자상수가 평균 0.0115$\AA$ 감소하였다.

• 한국세라믹학회지
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• 제36권7호
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• pp.725-733
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• 1999

It is a fundamental experiment to use blast-furnace slag in solidification/stabilization process. The compressive strength and leaching test of Pb and Cr doped samples were evaluated and the effects of heavy-metal ions on the hydration of slag was investigated. Sodium silicates(5wt%) was added as alkali-activator and the effects of replacing a part of slag with flyash or gypsum was also discussed. Pb ion was solidified by encapsulation of matrix. In of slag${\pm}$gypsum binder microstructure was densified by accelerating to form AFt/AFm phase and compressive strength was improved resulting in reducing leaching amount of Pb ion. Cr ion was solidified by substituting with Al ion in aluminate product. Slag+fly ash binder improved compressive strength and decreased leaching amount of Cr ion.

• 한국환경과학회지
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• 제7권5호
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• pp.697-705
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• 1998

$Pb^{2+}$ removal capacity and initial $Pb^{2+}$ removal rate were compared between non-biomaterials (granular activated carbon, powdered activated carbon, ion exchange resin, zeolite) and biomaterials (activated sludge, Aureobasidium pullulans, Saccharomyces cerevisiae). The $Pb^{2+}$ removal capacity of biomaterials were greater than that of non-biomaterials, generally. The $Pb^{2+}$ removal capacities of non-biomaterials and biomaterials were shown on the order of ion exchange resin ＞ zeolite ＞ granular activated carbon ＞ powdered activated carbon and A. pullulans ＞ S. cerevisiae ＞ activated sludge, respectively. In the initial $Pb^{2+}$ removal rate, the non-biomaterials showed powdered activated carbon ＞ granular activated carbon ＞ zeolite ＞ ion exchange resin and the biomaterials showed A. pullulans ＞ activated sludge ＞ S. cerevisiae. Comparing the $Pb^{2+}$ removal capacity and initial $Pb^{2+}$ removal rate of activated sludge with those of other non-biomaterials and biomaterials, activated sludge may have an availability on the removal of heavy metal ions by the economical and pratical aspects.

• 한국세라믹학회지
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• 제29권4호
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• pp.259-264
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• 1992

The crystal structures and the bonding characteristics in $(Ba_xPb_{1-x})TiO_3$ have been investigated by X-ray diffraction analysis and infrared spectrophotometry. As $Ba^{2+}$ ion in $BaTiO_3$ were substituted by $Pb^{2+}$ ion, the structures were changed to orthorhombic from tetragonal, and also the covalent character in Ti-O bond increased, and then the dielectric constants decreased gradually. In the mixed oxide containing $Pb^{2+}$ ion more than 50%, the change-transfer energy of titanium ion increased.

• 한국환경과학회지
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• 제9권4호
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• pp.325-330
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• 2000

The hydroxyapatite (HAp) for the present study was prepared by precipitation method in semiconductor fabrication and the crystallized at ambient to 95$0^{\circ}C$ for 30min in electric furnace. The ion-exchange characteristics of HAp for various heavy metal ions such as $Cd^{2+}, Cu^{2+}, Mn^{2+}, Zn^{2+}, Fe^{2+}, Pb^{2+}, Al^{3+}, and Cr^{6+}$ in aqueous solution has been investigated. The removal ratio of various metal ions for HAp were investigated with regard to reaction time, concentration of standard solution, amount of HAp and pH of solution. The order of the ions exchanged amount was as follws: $Pb^{2+}, Fe^{3+}>Cu^{2+}>Zn^{2+}>Al^{3+}>Cd^{2+}>Mn^{2+}>Cr^{6+}. The Pb^{2+}$ ion was readily removed by the Hap, even in the strongly acidic region. The maximum amount of the ion-exchange equilibrium for $Pb^{2+}$ ion was about 45 mg/gram of HAp. The HAp would seem to be possible agent for the removal of heavy metal ions in waste water by recycling of waste sludge in semiconductor fabrication.

• 한국환경과학회지
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• 제7권6호
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• pp.803-809
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• 1998

Heavy metal ions in water were removed using algal biomass as adsorbents. Absorbents were dried for 3 days, ground them by 40~60 mesh and then were swelled in a buffer solution for 1hr. After being packed in the column, commercially available standard solution of Cd(II) and Pb(II) ions were diluted to get the suitable concentration and then it was eluted with the rate of 1mι/min. Heavy metals on the adsorbents were recovered with nitric acid. More amounts of Cd(II) or Pb(II) ions in green algae, Ulva pertusa, than in brown algae, Sargassum horneri, were adsorbed. Pb(II) ion was adsorbed more than Cd(II) ion in both algae. The pH effect of adsorbed amounts of Cd(II), Pb(II) ions on the biomass was shown the following order ; pH 10.5 ＞ 8.5 ＞ 7.0 ＞ 5.5 ＞ 3.5. Recovery ratio of metal ions front algae is shown higher in acidic or neutral conditions than it in alkalic ones. Pb(II) ion is recovered relatively more than Cd(II) ion in our system.

• 한국결정성장학회지
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• 제8권2호
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• pp.307-314
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• 1998

졸-겔법을 이용하여 PZT박막을 제조하였다. 출발물질로는 Pb-acetate trihydrate, Zr-normal propoxide와 Ti-ispropoxide를 사용하였으며, 용매로는 2-Methoxyethanol과 iso- Propanol을 사용하였다. 기판에 따른 Pb 이온 및 Si 이온의 확산을 고찰하기 위해 bare Si와 열산화된 $SiO_2/Si$ 그리고 산화된 기판 위에 졸-겔 spin-coating법으로 $TiO_2$를 입힌 $TiO_2/SiO_2/Si$ 기판을 사용하였다. 박막의 치밀화 및 기판과의 접착상태는 SEM을 이용하였고, 상생성 온도는 XRD, 그리고 Pb 이온 및 Si 이온의 확산 정도는 ESCA를 사용하였다. 기판으로 bare Si 및 $SiO_2/Si$를 사용한 경우, $700^{\circ}C$에서 perovskite상을 얻을 수 있었으며, SiO2/Si 기판을 사용하여 Si의 막으로의 확산을 다소 방지할 수 있었다. $TiO_2/SiO_2/Si$기판을 사용한 경우, $500^{\circ}C$에서 perovskite상을 얻을 수 있었고, Pb 이온 및 Si 이온의 확산을 방지할 수 있었다.

• 환경위생공학
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• 제22권1호
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• pp.29-35
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• 2007

This study was examined adsorption ability of heavy metal Hg(I), Pb(II), and U(Vl) ion use of fruit from schizandra chinensis, The fruits of schizandra chinensis sample used breaking into fragments $50{\sim}100$ mesh. The sample solution was mixed fruits of schizandra chinensis and heavy metal ion. Each heavy metal ion of into solution was quantum analysis with ICP-AES. As the result, each condition of maxium adsorption ability of heavy metal ion was high in the range of pH 5-7, adsorption time was about 15 minutes, and the optimum temperature was $100^{\circ}C$. The heavy metal ion was increased adsorption in order of increasing concentration and in ethanol solution better than in aqueous solution.