The radiation damage induced in cerium dioxide CeO2 and cerium-gadolinium mixed oxides (Ce, Gd)O2-x was studied by micro-Raman spectroscopy diffuse UV-visible reflectance spectroscopy. Sintered samples of undoped for 1 mol% 5 Gd2O3 were irradiated at room temperature with 2.5-MeV Ar2+ 12-MeV Ar4+ ions up to high fluences (i.e. × 1014 cm−2 2.1 respectively). Raman spectra show that no amorphizat...

Abstract The effects of engineered nanoparticles (ENPs) in living organisms are described in a myriad of articles. Most of the literature on this topic is devoted to plants of different gender and species. Studies from laboratories and greenhouse facilities highlight effects on chlorophyll production, plant growth, stress enzyme activities, phytotoxicity, cytotoxicity, and genotoxicity. With fe...

The silicon–cerium oxide interface is studied using x-ray photoelectron spectroscopy. The oxidation and reduction of species at the interface are examined as a function of annealing temperature both in vacuum and oxygen ambient, in order to determine their relative stabilities. By depositing a very thin CeO2 film ~;30 Å!, the cerium and silicon core level peaks can be monitored simultaneously. ...

The rare earth cerium was found to bind rapidly to Escherichia coli. Cerium inhibited oxygen uptake in the presence of glucose as well as the endogenous respiration of glucose-grown cells. For a cell concentration of 4 mg per ml, maximal inhibition was obtained at 120 mug per ml. Greater concentrations did not increase the inhibitory effect. Cerium inhibited (14)CO(2) evolution and (14)C uptake...

Cerium oxides have attracted much attention because of their uses in three-way catalysts and other catalyst applications. The redox reaction of cerium oxides, as the basis of their use as catalysts, usually takes place at high temperature (>600 K) and/or low oxygen partial pressure. There have been continuous efforts to lower the operating temperatures of cerium oxide further to improve the per...

In the present study, a conversion layer mainly composed by cerium oxide was prepared by means of a novel ultrasound-assisted coating process. The formation of a conversion layer on top of the Mg alloy provides physical barrier properties improving the corrosion protection. In addition, the incorporation of cerium oxide within the coating enables the formation of a protective layer on the pores...

ABSTRACT Terbium fluoride nanocrystals, covered by a shell, composed of cerium fluoride were synthesized by a co-precipitation method. Their complex structure was formed spontaneously during the synthesis. The surface of these core/shell nanocrystals was additionally modified by silica. The properties of TbF3@CeF3 and TbF3@CeF3@SiO2 nanocrystals, formed in this way, were investigated. Spectrosc...

Due to their physicochemical characteristics, metal oxide nanoparticles (NPs) interact differently with cells compared to larger particles or soluble metals. Oxidative stress and cellular metal uptake were quantified in rat type II alveolar epithelial cells in culture exposed to three different NPs: manganese(II,III) oxide nanoparticles (Mn(3)O(4)-NPs), the soluble manganese sulfate (Mn-salt) a...

We report isotopic and chemical compositions of unusual tridymite–hercynite xenoliths in middle Miocene Niutoushan tholeiites from the southeast coastal area of China. These xenoliths are characterized by positive cerium (Ce) anomalies and extremely high Al2O3 (32–34 wt.%) and total iron oxide (20–22%). They have Sr/Sr of 0.7050–0.7058, eNd(0) values of + 3.2 to + 4.2, Pb/Pb ratios of 18.8–19.1...