• Journal of the Korean Chemical Society
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• v.53 no.5
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• pp.485-490
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• 2009

The inhibitive action of the aqueous extract of lawsonia, licorice root and carob toward the corrosion of tin electrode in 0.1 M $NaHCO_3$ solutions was investigated using galvanostatic polarization measurements. It was found that the corrosion rate decreases in the presence of these extracts indicating the inhibiting of these compounds. The inhibition efficiency increases with increasing extract concentration. The inhibition action of these extracts was explained in view of adsorption of its compounds onto the tin surface, making a barrier to mass and charge transfer. The adsorption of these extracts on the tin surface was found to be a spontaneous process and follow Freundlich adsorption isotherm. It is also found that these extracts provide a good protection to tin against pitting corrosion in chloride containing solution using potentiodynamic anodic polarization technique.

• Bulletin of the Korean Chemical Society
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• v.23 no.12
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• pp.1719-1723
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• 2002

1,5-diphenylcarbazone was immobilized on sodium dodecyl sulfate coated alumina. The alumina particle was effectively used for collection of mercury(II) and methylmercury cations at sub-ppb level. The adsorbed mercury was eluted with l mol $L^{-1}$ of hydrobromic acid solution. The mercury(II) was then directly measured by cold vapor atomic absorption spectrometry utilizing tin (II) chloride where as the total mercury was determined after the oxidation of methylmercury into the inorganic mercury. The methylmercury concentration was calculated by the difference between the value of total mercury and mercury (II). Mercury (II) and methylmercury cations were completely recovered from water with a preconcentration factor of 100 (for 1 L solution.) Relative standard deviation at Hg L ${\mu}gL^{-1}$ level 1.7%(n=8) and the limit of detection was 0.11 ${\mu}gL^{-1}$. The procedure was applied to spring water, well water and seawater and accuracy was assessed through recovery experiments.

• Resources Recycling
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• v.19 no.3
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• pp.45-51
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• 2010

Solvent extraction behavior of Sn(IV) from hydrochloric acid solution was investigated using TBP(Tri-butyl Phosphate) as an extractant. The experimental parameters, such as the concentration of HCl solution, chloride ions, extractant, and Sn were observed. Experimental results showed that the extraction percent of Sn was increased with increasing the hydrochloric acid and chloride ion concentration. More than 98% of Sn was extracted in 7.0 M HCl by 10% TBP. The optimum extraction stages of Sn for continuous extraction process was theoretically calculated by analysizing the McCabe-Thiele diagram. Stripping of Sn from the loaded organic phases can be accomplished by NaOH as a stripping reagent effectively and 99.3% of Sn was stripped by 2.0M NaOH solution.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.8 no.3
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• pp.487-492
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• 1998

Ultrafine particles of $SnO_2$ or $(Sn,Ti)O_2$ and thin films of $SnO_2$ were synthesized by introducing aqueous tin chloride solution into a high temperature argon inductively coupled plasma (ICP) generated under ambient pressure (the spray-ICP technique). As-deposited $SnO_2$ particles from each concentration of solution were all tetragonal $SnO_2$ crystallline phase and their mean size decreased in proportion to the increase of solution concentration. The mean size of $SnO_2$ particles was in the 10~40 nm range.

• Current Photovoltaic Research
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• v.11 no.3
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• pp.96-102
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• 2023

Sn-Pb narrow-bandgap perovskite solar cells, which is a light-harvesting layer thicker than 1.3 micrometers, is needed to enhance the low photocurrent. The fabrication of such a thick film through solution processing is a key challenge. Here, we studied and characterized the film by using a precursor solution of increased concentration, comparing it with the universally used 1-micrometer Sn-Pb perovskite film. The increase in molar concentration clearly induced thickness enhancement, but we observed that it also created numerous voids at the interface with bottom charge transporting layer. We hypothesized that these voids might hinder the increase in photocurrent associated with thickness enhancement. By introducing methylammonium chloride (MACl), we successfully fabricated Sn-Pb perovskite film with a thickness of 1.3 micrometer and no voids. Void-controlled Sn-Pb perovskite solar cells not only demonstrated superior short-circuit current density compared to those with voids but also operated smoothly under light exposure.

• Journal of the Korean Society of Safety
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• v.4 no.1
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• pp.71-74
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• 1989

The $\alpha$-Fe$_2$O$_3$ gas sensor, prepared by the precipitation of Fe(OH)$_3$ from a solution of iron(III) sulfate and tin (IV) chloride, was composed of fine particles and was superior in sensitivity to other $\alpha$-Fe$_2$O$_3$. The gas sensitivity was found to depend on the amounts of remaining sulfate ion the microstructure and a small amount of iron(II) species generated through the reduction of $\alpha$-Fe$_2$O$_3$. The sensing mechanism of $\alpha$-Fe$_2$O$_3$gas sensor was confirmed to be due to the reduction of $\alpha$-Fe$_2$O$_3$ to the low resistive Fe$_3$-xO$_4$ by combustible gas and to depend on the crystral structure.

• Applied Microscopy
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• v.20 no.1
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• pp.65-76
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• 1990

The effect of calcium-free reperfusion for 5, 10, and 15 minutes, respectively, followed by continuous reperfusion with normal Tyrode solution containing 1.0mM calcium chloride, after global ischemia in the isolated perfused guinea pig heart by Langendorff techniques was examined with transmission electron microscope. Compared to the nomal Tyrode solution-perfused control hearts, the 5 minute calcium-free-reperfused hearts showed loss or thickening of Z lines, focal sarcolemmal disruption, mitochondrial swelling, clumping of chroma-tin, intracellular fluid accumulation, and some separation of cell junctions, especially the fasciae adherentes. These changes became more severe in the hearts of 10 minute calcium-free reperfusion. Subsarcolemmal larger bleb and near complete separation of cell junctions were noticed. In the 15 minute calcium-free-reperfused hearts, irreversible ultrastructural changes including contraction bands, biazrre mitochondria, and sarcolemmal destruction were widely distributed. The severity of myocardial changes were in accordance with the duration of calcium-free reperfusion. These changes indicate that calcium-free reperfusion regardless of its duration could not salvage the post-ischemic myocardium probably due to development of calcium paradox.

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.03a
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• pp.135-135
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• 2003

This paper presents the preparation of SnO$_2$ films by Sol-Gel process and using spin coating method, and their sensing properties in CO gas. Experimental procedure consisted of following steps: (1) Tin chloride(SnCl$_4$) and Ammonium hydrogen carbonate (NH$_4$HCO$_3$) were used as precursors; (2) the Sol solution with concentration of about 10wt% SnO$_2$ was prepared from washed Gel-precipitate for spin coating step; (3) thereafter, the coating solution was dropped onto the alumina (Al$_2$O$_3$) substrate that was then spun, the spin coating was carried out with total 10 times; (4) finally, the films were calcined for 3 hours at 50$0^{\circ}C$ or higher temperature (600, 700, 800 or 90$0^{\circ}C$) in order to obtain various gram sizes. The average grain size was calculated by Scherrer's equation using main peaks in XRD spectra; meanwhile the thickness, microstructure and surface morphology of the films were observed by FE-SEM.

• Journal of Electrochemical Science and Technology
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• v.10 no.1
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• pp.61-68
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• 2019

Well aligned $SnO_2$-doped ZnO nanorods were prepared by single step or 2-step electrochemical depositions in a mixture solution of zinc nitrate hexahydrate, ammonium hydroxide solution and 0.1 M tin chloride pentahydrate. The morphologies of electrochemically deposited $SnO_2$-doped ZnO were transformed from plain (or network) structures at low reduction potential to needles on hills at high reduction potential. Well aligned ZnO was prepared at intermediate potential ranges. Reduction reagent and a high concentration of Zn precursor were required to fabricate $SnO_2$ doped ZnO nanorods. When compared to results obtained by single step electrochemical deposition, 2-step electrochemical deposition produced a much higher density of nanorods, which was ascribed to less potential being required for nucleation of nanorods by the second-step electrochemical deposition because the surface was activated in the first-step. Mechanisms of $SnO_2$ doped ZnO nanorods prepared at single step or 2-step was described in terms of applied potential ranges and mass-/charge- limited transfer.

• Korean Journal of Materials Research
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• v.18 no.2
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• pp.69-72
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• 2008

A sensor element array for combinatorial solution deposition research was fabricated using LTCC (Low-temperature Co-fired Ceramics). The designed LTCC was co-fired at $800^{\circ}C$ for 1 hour after lamination at $70^{\circ}C$ under 3000 psi for 30 minutes. $SnO_2$ sol was prepared by a hydrothermal method at $200^{\circ}C$ for 3 hours. Tin chloride and ammonium carbonate were used as raw materials and the ammonia solution was added to a Teflon jar. 20 droplets of $SnO_2$ sol were deposited onto a LTCC sensor element and this was heat treated at $600^{\circ}C$ for 5 hours. The gas sensitivity ($S\;=\;R_a/R_g$) values of the $SnO_2$ sensor and 0.04 wt% Pd-added $SnO_2$ sensor were measured. The 0.04 wt% Pd-added $SnO_2$ sensor showed higher sensitivity (S = 8.1) compared to the $SnO_2$ sensor (S = 5.95) to 200 ppm $CH_3COCH_3$ at $400^{\circ}C$.