Dispersions of Zirconia Nanoparticles Close to the Phase Boundary of Surfactant-Free Ternary Mixtures.

The achievement of a homogeneous dispersion of nanoparticles is of paramount importance in supporting their technological application. In wet processing, stable dispersions were largely obtained via surfactant or surface functionalization: although effective, the use of dispersant can alter, or even impair, the functional properties of the resulting nanostructured systems. Herein, we report a novel integrated modeling and experimental approach to obtain stable ZrO nanoparticle (NP) dispersions at native dimensions (about 5 nm) in homogeneous ternary mixtures of solvents (i.

Dust emission and dispersion from mineral storage piles.

Dust pollution is a complex problem of growing interest because of its environmental, health, economic and political impact. Environmental impact assessment methods for dust pollution management are often based on the simulation of dust dispersion, which requires a precise characterization of the source term and of the source parameters. The source term model should be as simple and as accurate as possible and requires low time consumption in order to be easily connected to a more complex algorithm for the dispersion calculations.

Emission of air pollutants from burning candles with different composition in indoor environments.

Candle composition is expected to influence the air pollutants emissions, possibly leading to important differences in the emissions of volatile organic compounds and polycyclic aromatic hydrocarbons. In this regard, the purity of the raw materials and additives used can play a key role. Consequently, in this work emission factors for some polycyclic aromatic hydrocarbons, aromatic species, short-chain aldehydes and particulate matter have been determined for container candles constituted by different paraffin waxes burning in a test chamber.

Definition of a short-cut methodology for assessing earthquake-related Na-Tech risk.

Na-Tech (Natural and Technological) refers to industrial accidents triggered by natural events such as storms, earthquakes, flooding, and lightning. Herein, a qualitative methodology for the initial assessment of earthquake Na-Tech risk has been developed as a screening tool to identify which situations require a much more expensive Quantitative Risk Analysis (QRA). The proposed methodology, through suitable Key Hazard Indicators (KHIs), identifies the Na-Tech risk level associated with a given situation (i.

Conversion of C5 into C6 cyclic species through the formation of C7 intermediates.

We have recently proposed that the addition of C2H2 to the cyclopentadienyl radical can lead to the rapid formation of the cycloheptatrienyl radical and, in succession, of the indenyl radical. These reactions represent an interesting and unexplored route for the enlargement of gas-phase cyclic species. In this work we report ab initio calculations we performed with the aim of investigating in detail the gas-phase reactivity of cycloheptatrienyl and indenyl radicals.

The peculiar kinetics of the reaction between acetylene and the cyclopentadienyl radical.

The cyclopentadienyl radical (cC(5)H(5)) is a fascinating molecule characterized by several peculiar properties, such as its high internal symmetry and resonance enhanced stability. This makes cC(5)H(5) one of the most abundant radicals present in high temperature gaseous environments, such as flames. Therefore it is generally considered an interesting candidate as the starting point of reaction pathways leading to the formation of polycyclic aromatic hydrocarbons (PAH) and soot in combustion processes.