• Journal of the Korean Applied Science and Technology
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• v.37 no.5
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• pp.1222-1228
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• 2020

The adsorption and ion exchange properties of tin phosphate were studied in an aqueous solution of KCl, varing the pH and metal ion concentration in the solution. The data were explained on the basis of chemical equilibrium. Tin phosphate behaved as an acidic ion exchanger and had an adsorption selectivity toward the bivalent transition metal ions in the following order : Cu⁺² > Co⁺² > Ni⁺². As in the case of a weekly acidic exchanger, the change in hydration of metal ions played the dominant role in determining the selectivity of tin phosphate. In all cases the extent of adsorption increased with an increase in temperature and concentration. The apperance of irregular kinks in the titration curves justified the presence of several exchangeable adsorption sites with different pKa values.

• Resources Recycling
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• v.25 no.4
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• pp.42-48
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• 2016

A research for the recovery of the metal with high purity from the waste tin plating solution was carried out. First, tin plating waste solution was tested to remove the organic substances and metallic impurities such as Fe, Zn, Na etc. using ion exchange resin having iminodiacetic functional groups (Lewatit TP 207). Second, the tin solution was purified to obtain the high purity tin solution using ion exchange resin having ethylhexyl-phosphate functional groups (Lewatit VPOC 1026). Finally, 99.98% of the high purity of tin metal can be recovered from the purified solution by cyclone type electrowinning method.

• Resources Recycling
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• v.24 no.3
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• pp.51-58
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• 2015

In order to recover tin from the waste tin plating solution, we used the ion exchange method using three types of ion exchange resins. The ion exchange resin with tertiary functional group(Lewatit TP 272) has not adsorption ratio of tin. The ion exchange resin with iminodiacetic functional group(Lewatit TP 207) has high adsorption ratio of tin, but impurity content in the recovered tin solution was relatively high. Whereas, in case of the ion exchange resin with functional group of ethylhexyl-phosphate(Lewatit VP OC 1026), adsorption ratio of tin was less than that of Lewatit TP 207. However, it was possible to remove impurities in the recovered tin solution by controlling the pH of the solution. High purity tin solution can be recovered by removing the organic materials with water washing process.

• Bulletin of the Korean Chemical Society
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• v.28 no.7
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• pp.1171-1174
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• 2007

We have developed an electrochemical immunosensor that combines the electrocatalytic property of carbon nanotube and the low background current of indium tin oxide (ITO) electrode. A partial monolayer of carboxylated single-walled carbon nanotube (CCNT) is covalently formed on an ITO electrode modified with amine-terminated phosphonic acid. Nonspecifically adsorbed avidin on the hydrophobic sidewalls of CCNT is used to immobilize biotinylated antibody and to reduce the nonspecific binding to CCNT. The biotinylated antimouse IgG bound on avidin and the antimouse IgG conjugated with alkaline phosphatase (ALP) sandwiches a target mouse IgG. ALP catalyzes the conversion of p-aminophenyl phosphate monohydrate into p-aminophenol, which is electrocatalytically oxidized to p-quinone imine on CCNT surface. Moderate electrocatalytic electrode obtained with the combination of CCNT and ITO allows low detection limit (0.1 ng/ mL).

• Bulletin of the Korean Chemical Society
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• v.30 no.4
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• pp.965-968
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• 2009

• 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.

• Nuclear Medicine and Molecular Imaging
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• v.40 no.2
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• pp.127-131
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• 2006

Radiosynovectomy has been used as an effective treatment in patients with resistant synovitis after failure of long-term medication and intraarticular steroid injection. Although $^{90}Y$ silicate/citrate, $^{186}Re$ sulfide, and $^{169}Er$ citrate were approved in Europe for the appropriate radiopharmaceuticals for radiosynovectomy other radionuclides such as $^{32}P$-chromic phosphate, $^{165}Dy$-ferric hydroxide macroaggregate, $^{188}Rh$-microspheres, $^{153}Sm-particulate, and $^{166}Ho$-ferric hydroxide macroaggregate have been used in many countries. Reported success rates range from 40% to 90% for the different joints and underlying disease. In Korea, $^{188}Re$-tin-colloid and $^{166}Ho$-chitosan complex are now using as the major radionuclides in radiosynovectomy with good clinical results. A study on radiation synovectomy using $^{188}Re$-tin-colloid for patients with Korean rheumatoid arthritis shows the treatment resulted in the improvement of arthritis and well tolerated in our study, the radiosynovectomy with $^{166}Ho$-chitosan complex in 53 hemophilic patients markedly decreased intra-articular bleeding frequency and need for coagulation factor. This review inculdes general priciples in the application of radiosynovectomy and the clinical experience in Korea.

• Bulletin of the Korean Chemical Society
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• v.21 no.7
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• pp.709-711
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• 2000

Oxidizing metal complex mediates the electrochemical oxidation of guanine nucleotides. This catalysis results in an enhancement in cyclic voltammograms that yield the rate constant for the oxidation of guanine by the metal complex via digital simulation. The rate constant of oxidation of guanine by Ru(bpy)3(3+) is 6.4 x 10(5)M(-1)s(-l). The rate constant and the enhanced current depend on the number of phosphate groups on the sugar of nucleotidc. Also the modified guanine bases show different oxidation rate constants following the trend guanine-5'- monophosphatc (GMP) > 8-bromo-guanine-5'-monophosphate (8-Br-GMP) > xanthosine -5'-monophosphate (XMP) > inosinc-5'-monophosphate (IMP). The guanine bases derivatized differently are all distinguishable from one another, providing a basis for studying electrochemistry of DNA and RNA and developing electrochemical biosensors.

• Restorative Dentistry and Endodontics
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• v.19 no.1
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• pp.64-72
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• 1994

Zinc Phosphate Cement hand been used for about more than 100 years in luting of cast gold inlay. But many scientists had been trying to develop the new form of luting agent because the ZPC hand shown the lack of adhesiveness on the tooth structure and the toxicity to the pulp tissue. Recently many researches about the surface treatment of the cast body are being done to increase the adhesion of cement to it. The conventional Class I gold inlays were fabricated in the 20 permanent molars. After the internal surface of the cast body was sandblasted with $Al_2O_3$ particles and was tin-plated, the inlays were cemented with adhesive cement [G I cement and resin cement(Super-Bond & $Panavia_{EX}$)] and the evaluation on the adhesion pattern, adhesive strength and the fracture pattern of the adhesive cast gold inlay was compared to that of the cast gold inlay cemented conventionally with ZPC. The results were as follows : 1. The surface roughness of the cast body was increased significantly after sandblasting with the $Al_2O_3$ particles and the tin oxide layer, which was consisted of round particles, came into being. 2. The bond strength was in the order of Super-Bond, ZPC, Fuji I, $Panavia_{EX}$ group. The group cemented with Super-Bond showed statistically greater strength than the other groups(p<0.05). 3. The group cemented with ZPC was fallen apart by principal adhesion failure and that with Fuji I was by complete adhesion failure. But the group with Super-Bond showed pricncipal cohesive failure pattern and in the group with $Panavia_{EX}$, complete cohesive fracture pattern was shown and small protion of tooth structure was fractured out with cast body and the fractured surface showed the figure just as the enamel prism. 4. Various gaps were shown at the pulpal side regardless of little gap at the side walls of the cavity in all groups. Only the Super-Bond was attached to the tooth structure and the other cements were detached from both the tooth and the cast body.

• Journal of Conservation Science
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• v.36 no.1
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• pp.47-59
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• 2020

Scientific analysis was conducted to identify the paint pigments used in the Buseoksa Josadang murals. optical microscopy(OM), X-ray fluorescence(XRF), XRF mapping, scanning electron microscopy-energy dispersive X-ray spectroscopy(SEM-EDS), and Raman spectroscopy were performed to examine the pigments. The results confirmed that the Josadang murals consist of two paint layers wherein the pigments were distinct for most colors. It was estimated that celadonite, white clay, red ochre, cinnabar and minium, synthetic green pigment containing tin and zinc paratacamite, or botallackite were used in the upper layer. In addition, bone white, celadonite, red ochre, azurite, cinnabar or vermilion, and gold were identified in the lower layer. In addition, as Zn and Sn were detected in the green pigments extracted from the top layer of the paint, it is believed that Josadang murals were repainted over the original paint layer at some point after the 17th century. In addition, white pigments containing calcium phosphate were found in all the colors in the bottom layer, which is the original paint layer. These results are significant because this is the first time that white pigments are found in Korean traditional paintings. Additionally, the information revealed about the pigments in this study will serve as areference for the pigments used in the Goryeo period.