• Korean Journal of Materials Research
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• v.4 no.8
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• pp.934-944
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• 1994

Effects of residual chloride on thermal decomposition behaviour of a-stannic acid and physical properties of $SnO_{2}$ powder were observed. The powder was fabricated by hydroxide method; $\alpha$-stannic acid was precipitated by mixing acqueous solutions of $SnCl_{4}$ and $NH_{4}$OH . The precipitate was washed with $NH_{4}NO_{3}$ solution while washing was controlled to be of three grades to modify its residual chloride content. The precipitate was dried at $1100^{\circ}C$ ~ 24h and calcined in air at $500^{\circ}C$ ~ $1100^{\circ}C$ for one hour. Thermal decomposition behaviour of $\alpha$-stannic acid was examined by a DT-TGA and a FTIR. Chemical composition and physical properties of $SnO_{2}$ powder were observed by an AES, a BET and a TEM, respectively. With a reduction in chloride content, the relative crystallite size of $SnO_{2}$ powder slightly increased by a low-temperature-calcining. However, at a high calcining temperature(T), the reverse relation occured. It was suggested that chloride ion replaces part of lattice oxygen site of a-stannic acid. Also, chloride ion on the site was suggested to retard de-hydration as well as crystalization at a low T while to promote crystal growth of $SnO_{2}$ by forming oxygen vacancy at a high T.

• Journal of the Korean Ceramic Society
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• v.13 no.2
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• pp.8-16
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• 1976

The conductive transparent film is prepared by spraying thin salt solution. In stannic chloride solution as a base solution, various dopants such as Al, Co, Cu and Ni were dissolved respectively as a chloride state and then the films were made by spraying solutions on hot glass plates. The properties of them were compared with those of the stannic salt single component film. The films doped with copper oxide and nickle oxide were improved by decreasing their sheet resistivity and temperature coefficient of resistivity. In comparison with the sheet resistivity and temperature coefficient of resistivity of stannic oxide single component film, being 2.5 K ohm/$\textrm{cm}^2$ and -1650ppm/$^{\circ}C$ respectively, its values of the film containing 15 mol % of copper oxide and formed at 40$0^{\circ}C$ were 2.5K ohm/$\textrm{cm}^2$ and -920ppm/$^{\circ}C$ respectively. The film containing 15 mol % of nickel oxide and formed at 50$0^{\circ}C$ has shown its sheet resistivity and temperature coefficient 0.7 K ohm/$\textrm{cm}^2$ and -940ppm/$^{\circ}C$ respectively.

• YAKHAK HOEJI
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• v.40 no.6
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• pp.640-645
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• 1996

5-Alkyl-2(3H)-benzofuranones(3a-e) were prepared from Friedel-Crafts reaction of 4-alkylphenols with methyl 2-chloro-2-(methylthio)acetae(1) followed by the treatment of zinc du st-acetic acid. The reaction of disubstituted phenols with 1 in the presence of stannic chloride afforded 3-methyltWa-2(3H)-benzofuranone derivatives(11a-c), which were readily converted into 2(3H)-benzofuranone derivatives(12a-c) by desulfurization with zinc dust-acetic acid.

• Bulletin of the Korean Chemical Society
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• v.16 no.7
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• pp.609-613
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• 1995

The reaction of chloro(methylthio and arylthio)methanephosphonate (1) and Pummerer-type reaction of sulfinylmethanephosphonate (2) with nucleophiles such as aromatic compounds and thiols were examined. The direct chlorination of (methylthio and arylthio)methanephosphonate with N-chlorosuccinimide (NCS) led to the formation of monochlorinated phosphonates (1) in good yield. The reaction of 1 with aromatic compounds and thiols in the presence of stannic chloride afforded a variety of aryl(methylthio)methanephosphonates (3) and thioacetals of formylphosphonates (4), respectively. Phosphonates 3 and 4 were also obtained from the reaction of Pummerer intermediate, generated from sulfinylmethanephosphonate (2), with aromatic compounds and thiols, respectively. A versatile reaction conditions to generate Pummerer intermediate were examined. The best condition was the combination of trifluoroacetic anhydride with stannic chloride. All reactions may involve an initial formation of α-phosphoryl thiocarbocation and a subsequent nucleophilic attack of aromatic compounds and thiols.

• Textile Coloration and Finishing
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• v.5 no.1
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• pp.10-18
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• 1993

Epoxy compound was synthesized from bisphellol-A with epichlorophydrine. Epoxy compound and siloxane were emulsified conjugative one or another. The water repellency of silk fabrics was also highly improved by the treatment of epoxy-siloxane mixed emulsions containing stannic chloride and zirconium oxychloride. The maximum wrinkle recovery was obtained from the fabrics treated under the condition 2.5%-epoxy-siloxane emulsion at 16$0^{\circ}C$. The breaking elongation, the reflectance, the tensile strength and the bending properties of silk fabrics were not degraded severely by the treatment of epoxy-siloxane emulsion.

• Resources Recycling
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• v.30 no.2
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• pp.24-30
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• 2021

Dismantling tests were performed to separate components from waste printed circuit boards (PCBs) using HCl solution with Sn4+. Then, the effects of agitation speed, reaction temperature, initial Sn4+ concentration, and HCl concentration on the dismantling of components were investigated. No significant effect on the dismantling speed was observed upon changing the agitation speed from 100 to 300 rpm. However, the dismantling rate increased with increasing reaction temperature, Sn4+ concentration, and HCl concentration. In the all-component dismantling tests, when the dismantling ratio increased to 100%, no solder was observed on the boards, and the Sn4+ concentration was ~1,500 mg/L. The dismantling ratio of the components from the PCB increased to 100% within 2 h when 1 mol/L HCl solution with 10,000 mg/L Sn4+ was used at an agitation speed and temperature of 200 rpm and 90 ℃, respectively.

• Korean Journal of Materials Research
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• v.25 no.1
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• pp.27-31
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• 2015

This paper proposes a novel way of fabricating aligned porous Sn by freeze-drying of camphene slurry with stannic oxide ($SnO_2$) coated Sn powders. The $SnO_2$ coated Sn powders were prepared by surface oxidation of the initial and ball-milled Sn powders, as well as heat treatment of tin chloride coated Cu powders. Camphene slurries with 10 vol% solid powders were prepared by mixing at $50^{\circ}C$ with a small amount of oligomeric polyester dispersant. Freezing the slurry was done in a Teflon cylinder attached to a copper bottom plate cooled at $-25^{\circ}C$. Improved dispersion stability of camphene slurry and the homogeneous frozen body was achieved using the oxidized Sn powder at $670^{\circ}C$ in air after ball milling. The porous Sn specimen, prepared by freeze-drying of the camphene slurry with oxidized Sn powder from the heat-treated Sn/tin chloride mixture and sintering at $1100^{\circ}C$ for 1 h in a hydrogen atmosphere, showed large pores of about $200{\mu}m$, which were aligned parallel to the camphene growth direction, and small pores in their internal walls. However, $100{\mu}m$ spherical particles were observed in the bottom part of the specimen due to the melting of the Sn powder during sintering of the green compact.

• Bulletin of the Korean Chemical Society
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• v.32 no.9
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• pp.3295-3305
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• 2011

Thermal behavior of poly (methyl methacrylate) was analyzed in the presence of tin (IV) chloride. Five different proportions - polymer to additive - were selected for casting films from common solvent. TG, DTG and DTA were employed to monitor thermal degradation of the systems. IR and py-GC-MS helped identify the decomposition products. The blends start degrading at a temperature lower than that of the neat polymer and higher than that of the pure additive. Complex formation between tin of additive and carbonyl oxygen (pendent groups of MMA units) was noticed in the films soon after the mixing of the components in the blends. The samples were also heated at three different temperatures to determine the composition of residues left after the expulsion of volatiles. The polymer, blends and additive exhibited a one step, two-step and three-step degradation, respectively. $T_0$ is highest for the polymer, lowest for the additive and is either $60^{\circ}C$ or $70^{\circ}C$ for the blends. The amount of residue increases down the series [moving from blend-1 (minimum additive concentration) to blend-5 (maximum additive concentration)]. For blend-1, it is 7% of the original mass whereas it is 16% for blend-5. $T_{max}$ also goes up as the concentration of additive in the blends is elevated. The complexation appears to be the cause of observed stabilization. Some new products of degradation were noted apart from those reported earlier. These included methanol, isobutyric acid, acid chloride, etc. Molecular-level mixing of the constituents and "positioning effect" of the additive may have brought about the formation of new compounds. Routes are proposed for the appearance of these substances. Horizontal burning tests were also conducted on polymer and blends and the results are discussed. Activation energies and reaction orders were calculated. Activation energy is highest for the polymer, i.e., 138.9 Kcal/mol while the range for blends is from 51 to 39 Kcal/mol. Stability zones are highlighted for the blends. The interaction between the blended parts seems to be chemical in nature.

• Archives of Pharmacal Research
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• v.21 no.4
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• pp.465-469
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• 1998

The search for platinum (II)-based compounds with improved therapeutic properties was prompted to design and synthesize a new family of water-soluble, third generation cis-diaminedichloroplatinum (II) complexes linked to uracil and uridine. Six heretofore unreported uracil and uridine-platinum (II) complexes are; [N-(uracil-5-yl-methyl)ethane-1,2-di-amine]dichloroplatinum (II) (3a), [N-(uracil-6-yl-methyl)ethane-1,2-diaminel dichloroplatinum (II) (3b), t[N-($2^1$, $3^1$,$5^1$-tri-O-acetyl)uridine-5-yl-methyl] ethane-1,2-diamineldichloroplatinum (II) (6a), {[N-($2^1$,$3^1$, $5^1$-tri-O-acetyl) uridine-6-yl-methyl]ethane-1,2-diamine)dichloroplatinum (II) (6b),[N-(uridine- 5-yl-methyl)ethane-1,2-diamine]dichloroplatinum (II) (7a), [N-(uridine-6-yl- methyl)ethane-1,2-diamine]dichloroplatinum (II) (7b). These analogues were prepared from the key starting materials, 5-chloromethyluracil (1a) and 6-chloromethyluracil (1b) which were reacted with ethylenediamine to afford the respective 5-[(2-aminoethyl)aminol methyluracil (2a) and 6-[(2-aminoethyl)amino]methyluracil (2b). The cis-platin complexes 3a and 3b were obtained through the reaction of the respective 2a and 2b with potassium tetrachloroplatinate (II). The heterocyclic nucleic acid bases 1a and 1b were efficiently introduced on the .betha.-D-ribose ring via a Vorbruggen-type nucleoside coupling procedure with hexamethyldisilazane, trimethylchlorosilane and stannic chloride under anhydrous acetonitrile to yield the stereospecific .betha.-anomeric 5-chloromethyl- $2^1$,$3^1$,$5^1$-tri-O-acetyluridine (4a) and 6-chloromethyl-$2^1$,$3^1$,$5^1$-tri-O-acetyluridine (4b), respectively. The nucleosides 4a and 4b were coupled with ethylenediamine to provide the respective 5-[(amino-ethyl)aminolmethyl-$2^1$,$3^1$,$5^1$-tri-O-acetyluridine (5a) and 6-[(aminoethyl)amino] methyl-$2^1$,$3^1$,$5^1$-tri-O-acetyluridine (5b). The diamino-uridines 5a and 5b were reacted with potassium tetrachloroplatinate (II) to give the novel nucleoside complexes, 6a and 6b, respectively which were deacetylated into the free nucleosides, 7a and 7b by the treatment with CH$_{3}$ONa. The cytotoxic activities were evaluated against three cell lines (FM-3A, P-388 and J-82) and none of the synthesized compounds showed any significant activity.