Tin Hydroxide Research Articles

Adsorption of Copper Ion with Metal Hydroxide from Ammonia Solution

Abstract The removal of copper(II) from ammonia solution by adsorption on iron (III), aluminum(III), and tin(IV) hydroxide is studied. The effects of experimental parameters such as solution pH and concentration of total ammonia on adsorption are examined both from the change of solution composition and electrical properties of the solid surface. In a moderately high electrolyte concentration, an optimum solution pH is found for the solution composition when the sum of the species fractions of Cu(NH3)2+, Cu(NH3)2 2+, and Cu(NH3)3 2+ reaches its maximum. The ligand number of aminecopper(II) of the solution is near 2.0 under this optimum condition. The decrease in adsorption in the more basic tetraamminecopper(II) solution is attributed to the competing reaction for copper(II) by the free ammonia in the solution. Adsorption isotherms at various concentrations of total ammonia show decreasing adsorption with high electrolyte concentration as a result of a highly positively charged surface and a reduction of ...

Effects of chemically induced maternal toxicity on prenatal development in the rat

The hypothesis that chemically induced overt maternal toxicity induces a characteristic syndrome of adverse developmental effects in the rat was investigated. Pregnant animals (Sprague-Dawley strain) were dosed by oral gavage with one of a series of compounds on days 6-15 of gestation. These chemicals were diquat (DIQ), ethylene-bis-isothiocyanate (EBIS), toxaphene (TOX), styrene (STY), 2,4-dichlorophenoxyacetic acid (2,4-D), 2,4,5-trichlorophenol (2,4,5-Tr), triphenyl tin hydroxide (TPTH), and cacodylic acid (CAC). The compounds were chosen because they exhibited little or no developmental toxicity in previous studies. Dosage levels producing maternal weight loss and/or lethality were determined from preliminary toxicity studies. Significant maternal weight reductions were noted during the course of treatment with all compounds except CAC and 2,4,5-Tr. Maternal lethality was produced by EBIS, TOX, 2,4,-D, and 2,4,5-Tr. The main treatment-related developmental toxicity noted in litters at term consisted of increased lethality (EBIS, TPTH) and decreased fetal weight (EBIS and CAC). Treatment-related anomalies were seen in litters treated with 2,4-D and TOX (supernumerary ribs) and with EBIS and STY (enlarged renal pelvis). No significant developmental effects were produced with DIQ, or 2,4,5-Tr. This study indicates that overt maternal toxicity as defined by weight loss or mortality is not always associated with the same defined syndrome of adverse developmental effects in the rat.

Solid catalyst treated with anion: XIX. Synthesis of the solid superacid catalyst of tin oxide treated with sulfate ion

A solid superacid catalyst with an acid strength of Ho ⩽ −16.04 was synthesized from tin hydroxide, which was obtained from the solution of pH 10, by exposing to 3 M H 2SO 4 followed by calcination in air at 823 K; the catalyst, SO 2- 4/SnO 2, was active for the skeletal isomerization of butane to isobutane at room temperature. The specific surface area of SO 2- 4/SnO 2 was much larger than that of SnO 2 without the sulfate treatment; by X-ray diffraction (XRD) analysis the degree of crystallization of the former material was much lower than that of the latter. Infrared (IR) spectra showed the catalyst to possess a bidentate sulfate ion coordinated to the metal. The present superacid showed the catalytic action of oxidation at elevated temperatures of >450 K; acetaldehyde and acetone were obtained as products from the hydration of ethene, and high selectivity of >95% for the formation of cyclohexanone from cyclohexanol was observed in the presence of water.

Mechanism of improved corrosion resistance of Zn-containing dental amalgams.

The aim of this study was to determine the mechanism of improved corrosion resistance of Zn-containing dental amalgams. Two Zn-containing conventional amalgams, their Zn-free counterparts, and three experimental amalgams (SnHg, ZnHg, and SnZnHg) were evaluated by the potentiodynamic polarization technique in 1% NaCl solution. The main difference between the two types of amalgams was found in their respective breakdown potentials at which passivity was destroyed. The breakdown potential of Zn-containing amalgams was about 200 mV more positive than that of the Zn-free amalgams. The improved stability of the Zn-containing amalgams has been attributed to the formation of a previously reported Zn stannate passive film which, according to the polarization data, is more resistant to the aggressive chloride ion than tin hydroxide that forms on Zn-free amalgams. The formation of Zn stannate was not found to affect the oxygen reduction reaction, the major cathodic reaction involved in the corrosion of dental amalgams.

ChemInform Abstract: Organotin Biocides. Part 10. Synthesis, Structure, and Biocidal Activity of Organotin Derivatives of 2‐Mercaptobenzothiazole, 2‐Mercaptobenzoxazole, and 2‐Mercaptobenzimidazole.

AbstractThe thioxo heterocycles (I) react with the tin hydroxides (II) under azeotropic conditions to form the stannyl sulfides (IIIa) ‐ (IIIc).

ChemInform Abstract: Synthesis, 119Sn‐NMR, and Moessbauer Studies and Bioassay Data of O‐Tricyclohexylstannyl Derivatives of Substituted 8‐Hydroxyquinolines.

AbstractThe hydroxyquinolines (I) react with the tin hydroxide (II) under azeotropic conditions to form the stannyloxy compounds (III).

Synthesis of the Solid Superacid of SO42−/SnO2 with Acid Strength of Ho≤−16.04

Abstract A solid superacid catalyst with an acid strength of Ho≤−16.04 was synthesized from tin hydroxide, which was obtained from the solution with pH=10, by exposing to 3 mol·1−1 H2SO4 followed by calcination in air at 823 K; the catalyst was active for the skeletal isomerization of butane to isobutane at room temperature.

Post-harvest chemical treatments for control of tuber infection byAlternaria solani

Post-harvest application of several chemicals, including captan, sodium hypochlorite, chlorine dioxide, triphenyl tin hydroxide, captafol, and iprodione signficantly (P=0.05) reduced infection of potato tubers (cv Norchip) byAlternaria solani. Application rates of 5.4 or 8.3 1 of chemical mixture/metric ton were effective although limited evidence indicated that the higher rate may provide additional control. Post-harvest treatments appeared to be effective when disease pressure, as measured by the numbers of lesions per tuber, was low to moderate and seemed to lose effectiveness when disease pressure was high. It is suggested that routine post-harvest applications of effective chemicals coupled with proper storage management in disease prone locations might be an economically feasible way to control early blight losses in storage.

Processes to produce superconducting Nb3Sn powders from Nb-Sn oxide

The superconducting compound Nb3Sn was produced by the reduction of the oxides or hydroxides of niobium and tin. The procedure consists of the following three steps; (i) preparation of the mixed oxides or hydroxides, (ii) direct alloy reduction, and (iii) homogenizing heat treatment of the reduced metal powders. For mixing the two oxides, two methods were tried: the simultaneous precipitation from the aqueous solution and the solidification of the molten oxides. These mixed oxides were reduced by ca!ciunn or magnesium vapour in the temperature range 973 to 1373 K. After calcium or magnesium oxide was removed by leaching the fine compound powder had an A-15 type crystal structure, but showed a relatively low superconducting critical temperature (T c). The isothermal annealing improvedT c to 18.0 K.

In Situ 119Sn Conversion Electron Mössbauer Study of the Surface of Tin Layers as Deposited by an Electroless Process

In situ 119Sn conversion electron Mössbauer spectroscopy has been used to investigate the process of autocatalytic (electroless) tin deposition in a strong alkaline solution using a rotating disk. It is very likely that a tin(II) compound—probably some tin(II) hydroxide complex—is present at the surface during the Sn‐metal depositing disproportionation reaction. The results obtained in a tin(II) solution with a pH of 6.1 indicate the presence at the surface of what is probably a tin(II) chloride compound.

Stability constants of tin(II) and calcium diphosphonate complexes

Stoichiometric stability constants were determined for tin(II) and calcium species with six different diphosphonates in 0.1 M Me 4NN0 3-containing solutions. Several protonated; hydroxylated, mono- and binuclear metal complexes have been identified. The relative amounts of these species present in aqueous solutions are strongly influenced by the pH Diphosphonates were found to be able to stabilize supersaturated tin(II) hydroxide solutions. The order of the observed increasing stability of tin(II) disphosphonates MDP < DPD < DCMDP ⋍ EHDP < pCPMDP is in accordance with the order of decreasing technetium-99m uptake in bone. The experimental data were obtained from acidimetric titrations. The stability constants were calculated from the titration curves by means of a computerized version of a nonlinear least-squares fitting procedure.

Mössbauer Study of Tin(II) Chloride Hydroxide and Tin(II) Hydroxide Oxide

Abstract The precipitates obtained by addition of a solution of NaHCO3 to a solution of SnCl2 at various pH were studied by thermal analysis, Mössbauer spectroscopy, and X-ray powder diffraction. The formula of the tin(II) chloride hydroxide precipitate obtained in the range of pH 1.9–2.5 was determined as 2SnO·SnCl2·H2O, or Sn3O(OH)2Cl2, and the formula of the hydroxide oxide obtained in the range of pH 7.0–7.7 was 3SnO·2H2O, or Sn3(OH)4O. In the intermediate pH range, the chloride ions were gradually replaced by hydroxide ions. The dehydration of hydroxide oxide to produce SnO occurred in two stages and the disproportionation reaction of SnO to SnO2 and β-tin proceeded via Sn2O3.

The dissolution and crystallisation of amphoteric metal hydroxides from sodium hydroxide solutions: Ionic equilibria, crystalline phases and crystallisation mechanisms

AbstractThe dissolution and recrystallisation of beryllium, zinc, cadmium and tin (II) hydroxides and chromium (III), iron(III), aluminium, scandium, yttrium, gallium and indium hydroxides, from sodium hydroxide solutions of concentrations C = 1 to 20 M at ambient temperatures, are surveyed. The different inic equilibria in metal hydroxide‐sodium hydroxide systems are examined: the phases crystallising from different sodium hydroxide solutions are tabulated and crystallisation mechanisms are analysed.

A New Variant of the Amphoterism of Tin(II) Hydroxide: Sn(OH)2 as Stannio Complex Ligand

A novel mode of fixing a transition metal to an amphoteric inorganic polymer has been accomplished in the complexes (2). Complexes having coordinative SnM bonds were formerly unknown. Sn(OH)2 is still highly associated in (2) (M = Cr, W; R = Ph, Me). equation image

Electrochemical behavior of Sn 8Hg (gamma-2) and dental amalgam in a phosphate buffer solution

The gamma-2 phase (Sn 8Hg) and a dental amalgam in phosphate buffer have been studied by means of potentiostatic and galvanostatic techniques, along with a rotating ring-disc electrode (RRDE). The analysis of results has shown that phosphate ions play an important role in the corrosion of amalgam. The anodic reaction leads to the formation of soluble species and a passivating film, which is probably composed of tin hydroxide and tin phosphate.

Cabbage Looper: Ovicidal Activity of Pesticides in the Laboratory1

Commercial formulations of 23 insecticides and fungicides were evaluated in the laboratory for ovicidal activity against 2 indigenous strains of the cabbage looper, Trichoplusia ni (Hubner). The laboratory strain had been reared continuously for ca. 3 yr while the field strain had been reared for 3–4 generations during the experiment. The field strain was more tolerant to the ovicides than the laboratory strain. Materials with most ovicidal activity were permethrin, Pydrin® (cyano (3-phenoxyphenyl) methyl-4-chloro-alpha-(l-methylethyl) benzeneacetate), methomyl, and chlordimeform. Other pesticides with lesser ovicidal activity (from lowest to highest LC50 of the field strain) were Mobil 9087 (l-ethoxy-4-{ 1-[4-(I, I-dimethylethyl) phenyl]-2-nitrobutyl} benzene), UC 51762 (dimethylester of N, N-[thiobis [(methylimino)carbonyloxy]] bisethanimidothioic acid), mevinphos, sulprofos, monocrotophos, and profenofos. Pesticides with no ovicidal activity were acephate, benomyl, chlorothionil, diflubenzuron, endosulfan, maneb, methamidophos, oxamyl, parathion, tetradifon, tetrasol, and triphenyl tin hydroxide.

Anodic behaviour of tin in neutral phosphate solution

The oxidation behaviour of tin in neutral phosphate solution at 37°C (pH = 6.7) has been examined by means of cyclic voltammetry, potentiostatic and galvanostatic pulse measurements. The results showed that the anodic reaction is controlled by diffusion. The passivation can be brought about by precipitation of soluble species and by nucleation and growth process at more anodic potential. Analysis of the passive layer indicated that it consists of a mixture of tin hydroxide and tin phosphate, or of tin hydroxide containing adsorbed phosphate species.

Acute and Subacute Toxicology and Safety Evaluation of Triphenyl Tin Hydroxide (Vancide KS)

The acute oral LD50 in Sprague-Dawley rats was determined to be 171 mg/kg (100-295) for males and 268 mg/kg (205-344) for females. 2. A 1 ppm dietary supplement of Vancide KS for 90 days did not induce any abnormalities in weanling Sprague-Dawley rats. The parameters evaluated were serum glutamic-oxaloacetic transaminase (SGOT), hematocrit, differential white blood cell count, food consumption, and weight gain, along with histologic studies of the myocardium, spleen, liver, kidney, stomach, and small intestine. A 500 ppm diet was lethal. Weanling and older rats subjected to 1000 and 10,000 ppm diets died within 5 days. 3. Vancide KS induced no acute dermal toxicity, nor did it exhibit percutaneous absorption in New Zealand strain albino rabbits. 4. Vancide KS induced no chronic dermal toxicity in New Zealand strain albino rabbits. 5. Vancide KS was not shown to be teratogenic. It exhibited an antifertility action, especially in Sprague-Dawley rats dosed on day 1 through day 7 of timed-pregnancy. 6. Vancide KS was shown to be an eye irritant which induces corneal opacity. 7. Acute oral toxicity studies in Sprague-Dawley rats indicate that Vancide KS should be classified as a toxic substance as defined in the regulations under the Federal Hazardous Labeling Act. 8. The intravenous administration of 25 mg/kg of Vancide KS to New Zealand strain albino rabbits induced death preceded by topic convulsions. 9. Vancide KS did not induce skin sensitization in male adult guinea pigs.

Reasons for the instability of the physicochemical properties of tin oxide obtained by the decomposition of tin hydroxides

Reasons for the instability of the physicochemical properties of tin oxide obtained by the decomposition of tin hydroxides

A Tin-119 Mössbauer Investigation of the Thermal Decomposition of Tin (IV) Hydroxides

A Tin-119 Mössbauer Investigation of the Thermal Decomposition of Tin (IV) Hydroxides