This study initiates the gradual upgrade of the DLR reaction database. The upgrade plan has two main steps: an optimisation of the C 1-C 4 oxidation chemistry and a revision of the polyaromatic hydrocarbon (PAH) formation sub-mechanism based thereupon. The present paper reports the main principles applied to model improvements and results obtained for the acetylene (C 2 H 2) oxidation sub-mechanisms. The principle acetylene oxidation reactions have been revised as well as the detailed chemistry of important intermediates, i.e. methylene, ethynyl, vinylperoxy radical and also diacetylene, vinylacetylene and higher diacetylenes, important for PAH formation. The uncertainty intervals of the studied reactions were statistically evaluated, providing general bounds for the performed modifications to reaction rate coefficients. The first stage of the presented update was performed through revision of the thermochemical data and model optimisation on ignition delay data and laminar flame speed data, since they exhibit lower uncertainty in comparison to species profile data. The final model optimization was obtained through simulations of concentration profiles measured in shock tubes and laminar flames for improvement of the reaction paths and rate coefficients related to acetylene pyrolysis and PAH precursor formation. Approximately 500 data points were analysed. The updated reaction mechanism predicts all simulated experimental data, also not included in the optimisation loop data prom plug flow and jet-stirred reactors, either with good or satisfactory agreement. It was found that the vinylperoxy radical formation and consumption dictate the reaction progress at low temperatures. The performed study clearly determined that acetylene combustion proceeds through the strongly coupled reaction paths of fuel oxidation and PAH precursor formation; the same species are involved in these parallel processes. Therefore, the self-consistent reaction model for acetylene combustion could be obtained only by an optimisation performed on the experimental dataset encompassing both processes.

The results of the study of the formation of graphene layers in the flame in premixed flame propane or butane-oxygen mixture on a nickel substrate at atmospheric pressure and low pressure are given. The influence of the ratio C/O and supply quantity of argon on the formation of graphene layers were researched. It is shown that in the flame of propane and butane on a nickel substrate is observed under these conditions the formation of predominantly 3-10 layers of graphene.

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<p>Nowadays numerous sorbents based on graphene and other carbon nanomaterials have been synthesized for the removal or collecting of oil remains due to its unique physico-chemical properties. Obtaining of aerogels based on graphene oxide and carbon nanotubes with addition of chitosan solution as a binder <br />component is shown in this paper. Aerogels were synthesized by reduction of aqueous dispersion of graphene oxide using the reducing agents, followed by ultrasonic and thermal treatment. Ultrasound destroys the graphene layers, decreasing them in size, thereby exposing new layers to form edges that already have no stabilizing carboxyl groups, which are located at the edges, and participate in the formation of bonds. The surface morphology of obtained aerogels was studied by SEM. The study of the sorption capacity showed that graphene/CNTs aerogel is characterized by short absorption time and high sorption ability that depend <br />on densities of the used solvents. All experimental results show the possibility of using the aerogels based on graphene and CNTs as sorbents for collection of oil residues.</p>

We synthesize and deposit carbon nanostructures through flame synthesis on silicon and nickel wafers at different nonpremixed flame locations to produce hydrophobic surfaces. The hydrophobicity is characterized through the contact angle for water droplets placed on the surface. The surface morphology of the nanoparticles is obtained from SEM images. The morphology and hydrohobicity of the nanostructured surfaces depends upon the deposition, which differs at various flame locations. We determine the optimum flame location for the synthesis and deposition of surface carbon nanostructures that lead to maximum hydrophobicity.

Supercapacitors are one of the promising devices for the accumulation and storage of electrical energy. The purpose of this study is to develop a synthesis and modification method of carbon material to improve the electrochemical characteristics of a supercapacitor. In the proposed study, by varying the sequence and parameters of the processes of carbonization, mechanoactivation and thermochemical activation, the conditions for obtaining nanoporous carbon with a specific surface area of 2200 (±50) m2/g from walnut shells (WSs) are optimized. In addition, to increase the electrochemical efficiency of the electrode material, the resulting nanoporous carbon was modified with nickel oxide (NiO) nanoparticles by the thermochemical method. It is shown that the modification with nickel oxide nanoparticles makes it possible to increase the specific capacitance of the supercapacitor electrode by 16% compared to the original unmodified nanoporous carbon material.

The paper presents the results of studies on the synthesis of superhydrophobic soot, and on the development of its technology-based production of bulk material (sand), which has hydrophobic properties. The hydrophobic properties of sand had attached by fixing soot having superhydrophobic properties of nanoscale layer on the surface of the grains of sand. The resulting sand was examined by scanning electron microscopy to determine the structural and morphological parameters. The resulting composite material is characterized by good water repellent and resistant to external corrosive environments, which allows it to be used in civil and road construction, water-resistant layer for reclamation in hot and arid regions, and in areas where there is a need for bulk materials with hydrophobic properties.

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