In this paper we present results of a study on the yttrium doping in lead tungstate crystals. The crystal growth by modified Bridgman method is described. Results of trace analysis on raw materials and crystals are presented. The segregation coefficient of yttrium ions in lead tungstate crystals was determined. The scintillation emission and longitudinal transmittance spectra, light output, dec...

Lead Tungstate crystals for the CMS detector at LHC have to withstand severe levels of radiation. Presented here are measurement techniques and results on crystal behaviour under gamma irradiation from tests at ETH/PSI in conditions similar to what is expected during operation of the CMS electromagnetic calorimeter. Presented at International Workshop on Lead Tungstate crystals, Rome, Italy, Oc...

Anabaena variabilis ATCC 29413 has two distinct nitrogenases that function in heterocysts, a conventional Mo-nitrogenase and an alternative V-nitrogenase. Synthesis of these two enzymes was repressed in cells growing with a source of fixed nitrogen, such as ammonium; however, the V-nitrogenase was also repressed by Mo. Expression of the V-nitrogenase which was not affected by V and expression o...

SiO 2 /Bi WO 6 photocatalyst with Si/Bi/W=1:2:1 molar ratio was obtained by the sol-gel method from bismuth nitrate, sodium tungstate and biogenic silica rice husk biomass followed calcination. Bi used as a control sample. FT-IR, SEM, XRD, EDXRF, UV-Vis methods were to systematically characterize as-obtained materials. Photodegradation of Indigo Carmine in exposure UV, sunlight xenon light stud...

In this paper we present results of a study on the yttrium doping in lead tungstate crystals. The crystal growth by modified Bridgman method is described. Results of trace analysis on raw materials and crystals are presented. The segregation coefficient of yttrium ions in lead tungstate crystals was determined. The scintillation emission and longitudinal transmittance spectra, light output, dec...

It is known that oral administration of sodium tungstate preserves the pancreatic beta cell function in diabetic rats. Healthy and streptozotocin-induced diabetic rats were treated with sodium tungstate for one, three or six weeks, after which the species of W in serum, were analysed. An increase in serum W with treatment time was observed. After six weeks, the serum W concentration in diabetic...

The kinetics of cyclooctene epoxidation with H2O2 by micellar catalysis was studied. As catalyst, an ionic liquid (IL) containing the catalytically active tungstate anion used. IL forms micelles in aqueous phase. It is simply formed dissolving sodium and 1-octyl-3-methylimidazolium tetrafluoroborate [OMIM][BF4] H2O2. For catalysis, a power law kinetic model determined that takes critical micell...

Acetylene hydratase of the mesophilic fermenting bacterium Pelobacter acetylenicus catalyzes the hydration of acetylene to acetaldehyde. Growth of P. acetylenicus with acetylene and specific acetylene hydratase activity depended on tungstate or, to a lower degree, molybdate supply in the medium. The specific enzyme activity in cell extract was highest after growth in the presence of tungstate. ...