the fuel cells are distinguished as generating of green allocable energy and are electrochemical devices of low environmental impact. porous nanocrystalline strontium-doped lanthanum manganite la0.8sr0.2mno3 (lsm) cathode materials were prepared by mechanochemical route in various grinding times. carbon black was employed to produce pores. the formation of lsm single phase was studied by x-ray ...

Typical cathode materials of Li-ion battery suffer from a severe loss in specific capacity, and this problem is regarded as a major obstacle in the expansion of newer applications. To overcome this, porous cathodes are being extensively utilized. However, although it seems that the porosity in the cathode would be a panacea for high performance of LIBs, there is a blind point in the cathode con...

Skidding operations induce changes in soil physical properties, which have the potential to impact soil sustainability and forest productivity. Our objective was to investigate the effects of traffic frequency, trail slope, and soil moisture content on soil compaction, total porosity and rut depth. Treatments included a combination of three different traffic intensities (3, 7, and 14 passes), t...

Soil wettability is especially important for rainfed agriculture in climates with a dry period during the growing season. The effect of aggregate structure and soil organic C content on wettability of soil aggregates was determined for grassland (grass) and tilled fields (tillage). Soil organic C, plastic limit, aggregate total porosity, and wettability at 100 mm (rapid wetting) and 300 mm (slo...

in this research the composition of polyurethane closed cell (pucc) with two different concentrations of sio2 nanoparticles (1.0 and 2.0 wt%) have been prepared. optical microscopy and sem imaging, watering uptake, ftir and raman spectroscopy of the synthesized samples were carried out. the optical microscopy imaging of samples showed differences in the appearance of matrix produced by applying...

INTRODUCTION The aim of this study was to evaluate the effect of mechanical and manual mixing as well as the effect of ultrasonic agitation during placement on the flexural strength and porosity of mineral trioxide aggregate (MTA). METHODS White ProRoot MTA and white MTA Angelus were used. One gram of each powder was mixed with a 0.34-g aliquot of distilled water. Specimens were mixed either ...

Porosity is a characteristic present in most sintered materials, full densification only being achieved special cases. For some porosity indeed desired characteristic, serving for the intended application of material. In any case, materials can have strong effect on their properties, both structural and functional. this paper, expressions proposed to describe influence total effective propertie...