Metal-free carbon-based catalysts for oxygen reduction is synthesized with high activity selectivity and durability. The catalysts were synthesized by introducing oxygen and nitrogen groups from various oxygen and nitrogen precursors. The nature of nitrogen surface groups and the effect of pyrolysis temperature on the activity of the catalyst have been evaluated. XPS indicates that higher conce...

Under high pressure, triply bonded molecular nitrogen dissociates into singly bonded polymeric nitrogen, a potential high-energy-density material. The discovery of stable high-pressure forms of polymeric nitrogen is of great interest. We report the striking stabilization of cagelike diamondoid nitrogen at high pressures predicted by first-principles structural searches. The diamondoid structure...

We study the formation energies and repulsive interactions of monatomic steps on the TiN(001) surface, using density functional total-energy calculations. The calculated formation energy of [100] oriented steps agree well with recently reported experimental values; these steps are shown to have a rumpled structure, with the Ti atoms undergoing larger displacements than the N atoms. For steps th...

BACKGROUND Control of dust mites using extremes of temperature is an alternative to the use of acaricides. In the past we have attempted control by freezing with liquid nitrogen. The present paper deals with the opposite extreme, the use of steam. OBJECTIVE To assess the feasibility and effectiveness of a domestic steam cleaner for the control of dust mites, its effect on mite populations and...

This study was designed to investigate the effects of different tillage systems on some parameters such as soil salinity (pH, EC, SAR), soil density and nutrients in a nested experimental design with three treatments (no tillage, reduced tillage and conventional tillage) and three replications. Chenaran city fields were selected as the case study areas. Result of the statistical analysis indica...

the field study was conducted in one district of educational-experimental forest at tehran university (kheirood-kenar forest) in the north of iran. eighty-five soil profiles were dug in the site of study and several chemical and physical soil properties were considered. these factors included: soil ph, soil texture, bulk density, organic carbon, total nitrogen, extractable phosphorus and depth ...

objective(s): first-principles calculations have been carried out to investigate the interaction of aspirin molecule with nitrogen-doped tio2 anatase nanoparticles using the density functional theory method in order to fully exploit the biosensing capabilities of tio2 particles. methods: for this purpose, we have mainly studied the adsorption of the aspirin molecule on the fivefold coordinated ...

a filed experiment was conducted to assay the effect of nitrogen fertilization and cultivated density on essential oil content on dragonhead (dracocephalum moldavica) in semi-arid conditions in 100 km of south east of mashhad. the experiment was done as factorial based on randomized complete blocks design with three replications, factor included four levels of nitrogen fertilization (0, 50, 100...

in order to study the intercropping arrangements of coriander (coriandrum sativum l.) and fenugreek (trigonella foenum-graecum l.), a field experiment was conducted during growing season of 2010 at agriculture research station, college of agriculture, ferdowsi university of mashhad, iran. a randomized complete block design with three replications was used. treatments included: mono-crop of fenu...