Analysis of the physical properties, composition and structure of soot particles

A soot particle consisting of crystallites representing several parallel layers of densely packed hexagons with carbon atoms located at the vertices is considered. Such a crystallite structure is similar to a graphite crystal lattice, but less ordered with large distances between the layers, where individual layers can be arbitrarily rotated relative to each other and relative to their common normal. It is shown that the core of a particle with a high salt content of exhaust gases (EG) of a diesel internal combustion engine (DICE) is discharged more, which allows us to distinguish models of the structure of a spherical nanoscale particle.

The Effect of Ball Milling on Properties and Sintering of Nanostructured TiB2

TiB2 powder was milled in a high-energy ball mill (Pulverisette-5 planetary mill) at 250 rpm for various time periods (0, 1, 4, and 10 h) and consolidated by the high frequency induction heated sintering (HFIHS). The effect of milling on the sintering behavior and crystallite size of TiB2 powders were investigated. A nanostructured dense TiB2 specimen with a relative density of up to 98% was readily achieved within very short time (two min). The ball milling effectively refined the crystallite structure of TiB2 powders and facilitated the subsequent consolidation. The sinter-onset temperature was reduced remarkably by the prior milling for 10 h. Accordingly, the relative density and mechanical properties of TiB2 compact increased as the milling time increased.

Even Visually Intact Cell Walls in Waterlogged Archaeological Wood Are Chemically Deteriorated and Mechanically Fragile: A Case of a 170 Year-Old Shipwreck

Structural and chemical deterioration and its impact on cell wall mechanics were investigated for visually intact cell walls (VICWs) in waterlogged archaeological wood (WAW). Cell wall mechanical properties were examined by nanoindentation without prior embedding. WAW showed more than 25% decrease of both hardness and elastic modulus. Changes of cell wall composition, cellulose crystallite structure and porosity were investigated by ATR-FTIR imaging, Raman imaging, wet chemistry, 13C-solid state NMR, pyrolysis-GC/MS, wide angle X-ray scattering, and N2 nitrogen adsorption. VICWs in WAW possessed a cleavage of carboxyl in side chains of xylan, a serious loss of polysaccharides, and a partial breakage of β-O-4 interlinks in lignin. This was accompanied by a higher amount of mesopores in cell walls. Even VICWs in WAW were severely deteriorated at the nanoscale with impact on mechanics, which has strong implications for the conservation of archaeological shipwrecks.

Synthesis and Electrochemical Characterisation of Novel Hybrid Copper / Poly (diphenylamine) (PDPA) Nanocomposites

The Poly (diphenylamine) (PDPA) nanoparticles was synthesized by surfactant assisted dilute polymerization method and characterized by UV-Visible, FTIR and Cyclic Voltammetry techniques. The PDPA nanoparticles were then suspended in an acidified copper sulphate electrolytic bath to prepare Cu-PDPA nanocomposites by simple electrodeposition technique. The XRD analysis revealed that the crystallite structure of Cu-PDPA nanocomposites and pure copper coatings was crystalline fcc and the grain size was 32 nm for pure Cu and 27 nm for Cu-PDPA nanocomposites. This decrease in crystallite size of Cu-PDPA nanocomposites shows the inclusion of PDPA nanoparticles was uniformly distributed throughout the copper matrix. The microstructure of the Cu-PDPA nanocomposites was examined by SEM analysis shows cauliflower like crystallites with layer by layer outward growth compared to electrodeposited pure copper coatings. The Electrochemical AC impedance and Tafel polarization studies were performed for electrodeposited copper and Cu-PDPA nanocomposites in 3.5% NaCl solution. It revealed that the Cu-PDPA nanocomposite coatings were found to be more corrosion resistance than electrodeposited pure copper coating.

Nano SiC Reinforced Copper Nanocomposite by a Simple Electrodeposition Method

The Cu and Cu-SiCnanocomposite coatings were prepared by a simple electrodeposition technique from acidic copper sulphate electrolyte using SiC nanoparticles with an average particles size of 50 nm under optimized bath composition and preparation conditions for possible electrical contact material applications such as electrical switch and wiring boards where higher electrical conductivity and thermal conductivity is required. The scope of the present study is to enhance the strength, mechanical, corrosion and wear resistance properties of Cu-SiCnanocomposite compared to pure Cu coatings. The as prepared Cu and Cu-SiCnanocomposites were characterized for structural, mechanical and corrosion resistance properties by EDX, XRD, FESEM, Vickers microhardness tester and AC-impedance and Tafel polarization techniques. The elemental composition (wt% of Cu and SiC nanoparticles) of Cu-SiCnanocomposites was analyzed by EDX coupled with FESEM analysis confirms the presence of nanoSiC in the copper matrix and they were 89wt% of Cu and 11 wt% of SiC nanoparticles respectively. The surface morphology of Cu and Cu-SiCnanocomposites was studied by FESEM analysis shows that SiC nanoparticles were uniformly dispersed in the surface of the copper matrix compared to pure copper. The crystallite structure and grain size of the Cu and Cu-SiCnanocomposite electrodeposits was measured by XRD analysis. From the XRD results, the grain size calculated using Debye-Scherrer’s formula was ~35 nm for pure Cu and ~33 nm Cu-SiCnanocomposite. The crystallite structure of Cu and Cu-SiCnanocomposites was fcc (face centered cubic) and the preferred orientation of the plane was (220). The microhardness of Cu-SiCnanocomposite coating increased with increasing SiC nanoparticles concentration in the bath compared to pure Cu coating. The corrosion resistance measurements were performed for the pure Cu and Cu-SiCnanocomposite coatings by electrochemical impedance spectroscopy (EIS) and Tafel polarization techniques. It shows that, Cu-SiCnanocomposites has high corrosion resistance than pure Cu in 3.5wt% NaCl solution.