We call a module  essentially retractable if HomR for all essential submodules N of M. For a right FBN ring R, it is shown that: (i)  A non-zero module  is retractable (in the sense that HomR for all non-zero ) if and only if certain factor modules of M are essentially retractable nonsingular modules over R modulo their annihilators. (ii)  A non-zero module  is essentially retractable if and on...

Metal-containing mesoporous starches have been synthesized using a simple and efficient microwave-assisted methodology followed by metal impregnation in the porous gel network. Final materials exhibited surface areas >60 m² g-1, being essentially mesoporous with pore sizes in the 10-15 nm range with some developed inter-particular mesoporosity. These materials characterized by several technique...

Co3V2O8 thin nanoplates are firstly described as a kind of electrode material for supercapacitors. More importantly, from electrochemical measurements, the obtained Co3V2O8 nanoplate electrode shows a good specific capacitance (0.5 A g(-1), 739 F g(-1)) and cycling stability (704 F g(-1) retained after 2000 cycles). This study essentially offers a new kind of metal vanadium oxides as electroche...

By applying to electrolysis cathodes a technique that produces essentially only oxides that are volatile at room temperature, spectroscopically determined masses between 222 and 351 are found that cannot be ascribed to known compounds. In particular the masses found between 231 and 240 AMU cannot be ascribed to random signals but do correspond to CO2 the carbon of which is a neutron-rich nuclid...

We have hypothesized (Negro et al. 1999) that bearded vultures, Gypaetus barbatus, deliberately stain their plumage with iron oxides to signal dominance status. The conceptual frame to which we ascribe our hypothesis is the handicap principle (Zahavi & Zahavi 1997). For a signal to convey reliable information, and thus to evolve, it has to be costly (Zahavi 1975), and we proposed that the assoc...

In this study, a high energy planetary ball milling technique was used to synthesize nano-crystalline Mo-Cu alloys. Molybdenum trioxide (MoO3) and copper oxide (CuO) were used as the starting materials. Carbo-thermal co-reduction of mixed Mo and Cu oxides powders was done with milling followed by a heat treatment at a high temperature. Differential thermal analysis/thermogravimetric (DTA/TG) wa...