The hydroamination reaction offers a very attractive route for the synthesis of alkylated amines and their derivatives with no byproduct formation. Heterogeneous intermolecular hydroamination reactions of alkynes with aromatic amines using different inexpensive copper salts of hetropolyacid catalysts were investigated. Among heteropoly salts, copper salts of silicotungstic acid showed highest a...

The new Ka-band communications services require highly linear, high power amplifiers (HPAs). Traveling wave tube amplifiers (TWTAs) offer the best millimeter wave HPA performance in terms of power and efficiency, but are inferior to solid state power amplifiers (SSPAs) in linearity. This paper discusses techniques for improving millimeter wave HPA linearity. The significance and methods for eva...

We applied a polymerase chain reaction-sequence specific primer (PCR-SSP) method developed by other researchers to study 4 families of newborns with neonatal alloimmune thrombocytopenia (NAITP) in which serology had provided inconclusive human platelet antigen (HPA) typing data. This method allowed for the identification of the newborn HPAs which were incompatible with their respective mothers....

UV-Vis-NIR diffuse reflectance spectra of heteropoly acids of the type of H4PVMo11O40.xH2O were recorded with improved spectroscopic equipment for different times on helium stream at room temperature. A broad asymmetric absorption band with a maximum at 740-780 nm in the visible range and a shoulder at 900-1000 nm in the near infrared range is identified. With increasing time on stream the inte...

This paper is a brief review of our recent research into novel uses for heteropoly compounds as precursors for thin films that can be used as catalysts and materials with good optical, conductive and other characteristics. In view of this, we have chosen thin film obtained with 12-tungsphosphoric acid on aluminum substrates. In all cases, a relatively new, microarc oxidation technique has been ...

BACKGROUND Ascorbic acid is one of the most important vitamins to monitor in dietary sources (juices and vitamins) and biological liquids. RESULTS Silica and silica-titania xerogels doped with Mo,P-heteropoly compounds (HPC) have been synthesized varying titanium(IV) and HPC content in sol. Their surface area and porosity have been studied with nitrogen adsorption and scanning electron micros...