The study was designed to investigate the synergic effect of Ti and Sn in active metal brazing Al2O3 ceramic copper brazed, using multicomponent Ag-Cu-Zr filler alloy. Numerous fine hexagonal-shaped rod-like ternary intermetallic (Zr, Ti)5Sn3 phase (L/D = 5.1 ± 0.8, measured microns) were found dispersed Ag-Cu matrix Ag-18Cu-6Sn-3Zr-1Ti alloy, along with CuZrSn phases. An approximate 15° reduct...

ZnO-supported palladium-based catalysts have been shown in recent years to be both active and selective towards the steam reforming of methanol, although they are still considered to be less active than traditional copper-based catalysts. The activity of PdZn catalysts can be significantly improved by supporting them on alumina. Here we show that the Pd/ZnO/Al2O3 catalysts have better long-term...

CuInSe(2) nanowire arrays were fabricated by electrodeposition from aqueous solutions of copper sulfate, indium sulfate, selenium dioxide, and citric acid, using anodic alumina membranes as templates. X-ray diffraction patterns showed that the wires were single phase (chalcopyrite structure) but polycrystalline, and a band gap of ∼1 eV was obtained from optical measurements. TEM and SEM confirm...

: In this study, Ni and Cu nanowire arrays and Ni/Cu superlattice nanowire arrays are fabricated using standard techniques such as electrochemical deposition of metals into porous anodic alumina oxide templates having pore diameters of about 50 nm. We perform optical measurements on these nanowire array structures. Optical reflectance (OR) of the as-prepared samples is recorded using an imaging...

In this paper, a high-efficiency and stable Cu-Ce@?-Al2O3 catalyst was prepared by taking the reverse osmosis (RO) concentrated water of sewage treatment plant as object activated alumina carrier. The preparation factors that affected catalytic activity were investigated. SEM, EDS, XRD, BET, XRF, XPS techniques applied to characterize catalyst. Optimal working conditions, degradation mechanism ...

The paper aims to extend the current knowledge on electrical discharge machining of insulating materials, such as cutting ceramics used produce inserts machine nickel-based alloys in aviation and aerospace industries. Aluminum-based Al2O3, AlN, SiAlON are most demand industry but present a scientific technical problem obtaining sophisticated shapes. One existing solutions is using assisting tec...

Simultaneous application of colloidal processing and liquidforming additives to alumina resulted in a sintered density of >99% in 1 h at a temperature as low as 1070°C for a commercial high-purity alumina powder at a total dopant level of 2 mol%. The additives were 0.9% CuO + 0.9% TiOz + 0.1% B 2 0 3 + 0.1% MgO. At higher temperatures or after prolonged sintering, the doped alumina ceramic deve...

A comparison has been made of the infrared spectra of alumina with molybdenum oxide alumina in both the oxidized and reduced forms. In the case of molybdena-alumina prepared via adsorption of gaseous MoOp(OH)t, the spectra show that a practically complete monolayer of Mo6+ oxide covers the alumina. After reduction with hydrogen the hydroxyls of the carrier appear. From the reversibility of redu...

in this research new adsorbents were prepared by modification of surfactant-coated g-alumina with three ligands; 1-(2-pyridylazo)-2-naphtol (pan), dithizone (hdz) and dimetyl golyoxime (dmg). the adsorbents were used for removal and pre-concentration of pb+2, cd+2, ni+2, cu+2, co+2. aqueous solutions of the metal ions were passed through a column filled with the adsorbent and the retained catio...