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Infrared spectra of propionaldehyde was investigated over silica-supported Rh-Sn bimetallic catalysts. Two absorption bands of the carbonyl group were seen at 1670 and 1720/cm and the aldehyde hydrogen (-CH=O) was also seen at 2748 and 2848/cm over the Sn/Rh/SiO2 catalysts on which propionaldehyde was preadsorbed. The adsorbed species observed at 1670/cm in the infrared spectra was found to be one of the most effective surface adsorption states in the selective hydrogenation reaction of carbonyl groups in unsaturated compounds.

A novel method was developed for the synthesis of a family of dinuclear metal-metal bonded RhII2 carboxylate complexes possessing two syn chelate groups. The chelates were characterized as bidentate or tridentate units. The species that contained bidentate chelates exhibited reversible reduction processes that were ligand-based. Furthermore, the acetato trinuclear analogue exhibited a molecular structure that was composed of three pyridine terminal ligands.

Analysis of two textured Sn-added YBa2CuO (YBCO) samples developed by power melting reveals that substitution of Sn for Cu increases both the pinning potential and Jc value and decreases melting temperature. The melting temperature of one sample in air decreases to 955 degrees C. An increase in temperature reduces the maximum diamagnetism field. The Jc value measured by Bean's model decreases with the magnetic field.

Dialkylated, monoalkylated and nonalkylated tin surface complexes were formed when a well-defined surface organometallic fragment was grafted at the surface of two silicas, SiO2(200) and SiO2(500). The degree of dehydroxylation differentiated the two silicas. The choice of a starting tin complex was crucial for the control of surface organostannic fragment structure.

The chemical potential of tellurium in Pb(1-x(S))Sn(x(S))Se(1-y(S))Te(y(S)) solid solutions decrease with an increase in tin and tellurium concentrations. This phenomenon is attributed to the decreasing strain energy-driven segregation of tellurium from the solid to the liquid, as a result of an increase in tin concentration. Pb(1-x(s))Sn(x(s))Se(1-(y(s)))Te(y(s)) solid solution IV-VI semiconductor alloys can be grown by liquid phase epitaxy. Such materials facilitate the development of new, far-infrared tunable diode lasers.

The rate of departure of the leaving group cis, trans, cis-6-(trimethylstannyl)-e-decalyl tosylate is not increased when a trimethylstannyl group zeta occurs to tosylate along a zigzag channel of C-C bonds. Increase is observed in methods where tin is absent or when a solitary tin is observed in a non zigzag pathway. Solvent nucleophilicity influences the rate of the zigzags systems while ionizing power has a negligible effect on it. Replacement with reversal and deletion are the produces in aqueous ethanol.

Deep-level transient charge spectroscopy (QDLTS) is used to study the energy levels of tin in AlxGa1-xAs. QDLTS measurements that employ cyclic bias pulses to change the charge state of the tin centers are performed on two samples. An alternative deep-level transient spectroscopy algorithm is used to obtain the AlxGa1-xAs spectra. Results show that the spectra has multiple peaks, indicating the multilevel nature of the tin donors.

Graphite probe furnace atomic absorption spectrometry combined with exposure time experiment was used for vaporization and atomization analysis of lead and tin. This technique disclosed separate processes for vaporization and atomization of the two elements. Desorption from the graphite probe surface vaporized lead and tin as oxide molecules that dissociate in the gas phase in homogenous thermodynamic equilibrium. Rate constants and activation energies for the desorption of the oxide molecules were also determined.

Carboxylated Chromium(IV) (Cr(IV)) and Tin(II) (Sn(II)) form a system (Cr(IV)-Sn(II)) that provides evidence for Cr(II) intervention in a slow step and a quick follow up stem. Sn(II) acts as a metal center reductant. Cerium(III) acts as a catalyst undergoing a one electron reduction by Cr(IV), and is required for ligand anion oxidation. Cr(IV) is formed by reducing Cr(IV) in a buffer of branched alpha-hydroxy acids.

Electrical activation and carrier mobility of InP implanted with the group-IV elements at MeV energies as a function of implanted atom and rapid thermal annealing temperature was analyzed. The results show that electrical activation and carrier mobility increase and also saturate with increasing annealing temperature. PL emission intensity also increases as the annealing temperature increases. Sn shows the greatest electrical activation but the lowest carrier mobility.

The mechanism of whisker growth from Sn finish on Cu leadframe is examined under the temperature/humidity storage test. The results have shown that the reflowing process is a very good way for relieving Sn whisker growth in the Sn finish on the Cu leadframes.

Electrical and mechanical properties of selected tin-base solders Solder type Tensile properties Shear strength Antimonial-tin Cast: typical tensile strength, 40.7 Cast: 41.4 MPa solder MPa (5.9 ksi); elongation in 100mm […]

Tin-lead solders Solidus Liquidus Composition, % temperature temperature Tin Lead °C °F °C °F 2 98 316 601 322 611 5 95 305 581 312 594 10 90 268 514 […]

Tandem flowing afterglow selected ion flow tube technique is employed to study the Sn2 reaction of fluoride with methyl halides. Isotopic studies show inverse kinetic isotopic effects for deuteration of solvent and methyl halides. All these studies are done in gas phase.