The reaction mechanisms for diesel soot oxidation over V4/ZrO2 or V4/TiO2 oxide catalysts were studied by the means of in-situ UV-Raman spectroscopy. The results indicate that the formation of surface oxygen complexes (SOC) is a key step and the SOC species mainly exist as carboxyl groups. The presence of NO in the reaction gas stream can promote the formation of SOC species. For soot oxidation...

Introduction Conclusions References Tables Figures Back Close Abstract Introduction Conclusions References Tables Figures Back Close Abstract In the present study, the heterogeneous conversion of nitrogen oxide (NO) and nitrogen dioxide (NO 2) was studied at atmospheric humidity levels on flame soot surfaces, which were treated with gaseous nitric acid (HNO 3). In addition, the heterogeneous re...

Major pollutants emission from Direct-Injection (D.I) diesel engines are predicted by means of a mathematical model. In order to construct such a model, an integral Multi-Zone Combustion Model (MZCM) is formulated, which basically consists of jet mixing and combustion submodels. In MZCM, variation of injection pressure is considered. Also time period of ignition delay is predicted by considerin...

Soot volume fraction and number density in a turbulent diffusion flame burning kerosene/air were predicted using two approaches. The first used a conventional soot inception model based on the acetylene concentration and is referred to as the acetylene model. The second used a soot inception model based on the formation rate of three and two ring aromatics [1] and is referred to as the PAH ince...

Laminar, sooting, coflow diffusion flames at atmospheric pressure have been studied experimentally and theoretically as a function of fuel dilution by inert nitrogen. The flames have been investigated with laser diagnostics. Laser extinction has been used to calibrate the experimental soot volume fractions and an improved gating method has been implemented in the laser-induced incandescence (LI...

[1] The influence of anthropogenic aerosol (sulfate and soot) on upper tropospheric (UT) clouds through ice nucleation is studied using the NCAR Community Atmospheric Model Version 3 (CAM3) with a double moment ice microphysics treatment coupled to a global aerosol model (LLNL/UMich IMPACT). Present-day and preindustrial simulations are performed and compared for two scenarios. In the first sce...

A three-dimensional laminar non-buoyant diffusion flame was studied with the objective of improving the understanding of the soot production. The flame originated from a porous ethylene burner discharging into a laminar boundary layer. Soot volume fractions were measured using Laser-Induced Incandescence (LII) and the spontaneous emission from CH∗ was determined using chemiluminescence. The mai...

Crossed Fe2O3 nanosheets supported cobalt oxide nanoparticles on three-dimensionally macroporous nickel foam substrate (xCo/Fe-NF) was designed and successfully prepared through a facile hydrothermal and impregnation route. These catalysts showed high catalytic soot combustion activities under self-capture contact mode. The three-dimensional macroporous structures of Ni foam and the crossed Fe2...

A new instrument for the quantification of light absorption by particles collected on filters has been developed to address long standing environmental questions about light-absorbing in air, water, and snow ice. The Light Absorption Heating Method (LAHM) uses temperature changes when are exposed quantify absorption. Through use calibration standards, observed response unknown materials can be ...