Nowadays, proton exchange membrane fuel cells (PEMFCs) are the most promising green energy conversion devices for portable and stationary applications. Traditionally, these devices were based onperfluoro-sulfonic acid electrolytes membranes, given the commercial name Nafion. Nafion is the mostused electrolyte membrane till now; because of its high electrochemical properties su...

Recently, biomass-derived energy has been receiving more and more attention due to the depletion of conventional fossil sources at a faster rate, as well as major environmental issues.1 Biodiesel obtained by transesterification of vegetable oils and animal fats provides an alternative fuel option for the future.2 Transesterification of oils and animal fats produce glycerol in large excess (10 k...

The report involves a review of the most important work on coordination chemistry carried out in the Soviet Union during this decade in the field of platinum metals, rare earth elements, actinides, as well as complex compounds of elements from various groups of the D. I. Mendeleev Periodic System. The results obtained on studying heteropolyacids and complexes with different new types of ligands...

The epoxidation of limonene with hidrogen peroxide was studied over zeolite Tibeta (a large pore material) and heteropoly acids on carbono and alumina supported. PW11/C was catalyst the best tested. Introduction In the last years, the increase in environmental restrictions lead to the search for new oxydant systems to replace the traditionals in order to avoid the generation of polluting efflue...

Wells–Dawson tungsten heteropolyacid (H6P2W18O62) has been applied as an effective heterogeneous catalyst for one-pot synthesis of spiro[4H-pyran-3,3’-oxindoles] via reaction of various isatins, malonitrile and 1,3-dicarbonyl compound in water. The corresponding products were obtained in high yields. The catalysts were easily recycled and reused without loss of their catalytic activity. 

Lignocellulosic biomass is a very promising feedstock for the production of biobased chemicals. The C6 sugars (for example d-glucose, d-fructose, and d-mannose) in lignocellulosic biomass are interesting precursors for a broad range of chemicals with high application potential. Apart from fermentation to bioethanol and reforming to CO/H2, [10] the direct conversion of these sugars to useful pla...

Sparingly soluble Ion—association compounds Thrmed between multicharged anionic complexes ( formed from trace amounts of an element to be preconoentrated and determined) and hydrophobic basic dyes, accumulate at the phase boundary after shaking with a solvent of low polarity, This type of flotation (without surfactant and gas bubbling) depends on the acidity, the dyestuff and the flotation agen...

A new chemical deposition method has been developed to prepare photoconducting n-Sb2S3 thin polycrystalline films. The solution composition of the deposition bath was 0.025M potassium antimonyl tartarate, 0.4M triethanolamine, 0.025M thioacetamide, and 5 • 10-7M silicotungstic acid (STA), respectively. The as-deposited and the annealed films were characterized through x-ray diffraction, neutron...