The destruction of dichloromethane by a nonthermal plasma in atmospheric-pressure gas streams of nitrogen with variable amounts of added oxygen has been investigated. The identities and concentrations of the end products are determined by on-line FTIR spectroscopy, and the plasma chemistry is interpreted using a kinetic modeling scheme. Peak destructions of 20% are found for a deposited energy of 66 J L -1 . The maximum dissociation is found for a carrier gas that contains 1-3% O 2 , and the dissociation is greater in pure nitrogen than in an air stream. The major end products of the processing are HCN, Cl 2 , and HCl in pure nitrogen and CO, COCl 2 , HCl, and Cl 2 for gas streams containing oxygen. The plasma processing in streams containing oxygen also produces significant yields of nitrogen oxides. The mechanism of dichloromethane destruction in the plasma is predominantly oxidation initiated by atomic chlorine that is produced by collisions of dichloromethane with electronically excited nitrogen atoms and molecules. Because of low cross sections, electron attachment does not play a role in the destruction of dichloromethane. The addition of oxygen to the gas streams initially causes additional destruction from O and OH reactions, but further increase in the oxygen concentration causes inhibition of both the atomic chlorine cycle and the formation of NO x and a consequent reduction in dichloromethane destruction.

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Samples of several natural micas and a synthetic fluorphlogopite were heated at temperatures up to 850°C and then placed in NaCl.NaTPB solutions at 25°C to determine the effect of various heat treatments on the exchange ability of their interlayer K . The maximum degree of K exchange was generally unaltered when the samples were heated but major changes in the rate of ex change occurred. The K in muscovite was released much faster if the.samples were preheated at temperatures above 350°C and even faster if the temperature were raised to 725°C or the time of heating were increased. As a result, nearly complete exchange of K in <50/*muscovite particles was achieved in 1 week in stead of 2 years. On the other hand, the release of K by biotite and lepido melane was retarded by similar heat treatments. Lepidomelane was affected by temperatures as low as 250°C and to such an extent that samples heated at 450°C for 24 hours released only 65% of its K in 2 years instead of all its K in 1 week. Phlogopite was relatively unaffected by temperatures up to 650°C whereas fluorphlogopite exhibited a decrease in rate and degree of K exchange when heated at 450°C.

Wind blades are the most expensive parts of wind turbines made from fibre-reinforced polymer composites. The blades play a critical role on the energy production, but they are prone to damage like any other composite components. Leading edge (LE) erosion of the wind turbine blades is one of the common damages, causing a reduction in the annual energy production especially in offshore wind turbine farms. This erosion can be caused by rain, sand and flying solid particles. Coating the blade against erosion using appropriate materials can drastically reduce these losses and hence is of great interest. The sol–gel technique is a convenient method to manufacture thin film coatings, which can protect the blades against the rain erosion, while having negligible effect on the weight of the blades. This article provides an extensive review of the liquid erosion mechanism, water erosion testing procedures and the contributing factors to the erosion of the LE of wind turbine blades. Techniques for improving the erosion resistance of the LE using carbon nanotubes and graphene nano-additives are also discussed.

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Biotite samples (10–20 µm lepidomelane) were mixed with solutions that contained various oxidants (O2, NaOCl, H2O2, or Br2) and salts (NaCl, KCl, NaCl‐NaBPh4, or none) to compare the effectiveness with which these solutions oxidize structural Fe2+ at 25°C when customary procedures and mica samples at different stages of expansion are used. In general, the treatments that minimized interlayer K exchange did not oxidize detectable amounts of Fe2+, whereas those causing mica expansion oxidized equivalent fractions of the Fe2+ if they were given enough time. The rates of Fe2+ oxidation by the O2 and NaOCl‐O2 solutions were very slow in even the expanded mica and were similar enough to suggest the OCl‐ ions did not contribute to the process under these conditions. The Br2 and H2O2 treatments, on the other hand, oxidized 97 and 85% of the structural Fe2+ in a fully expanded mica, respectively, in a 24‐h period. The relative effects of Br2 and H2O2 solutions probably reflect differences in the oxidants themselves but are confounded by the low pH of the Br2 solution, NaBPh4 interactions and H2O2 decomposition. Indeed, all the results make it clear that more distinction needs to be made between the role of the oxidants and the side efects of the solutions and procedures that are used in oxidation experiments.

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In this paper we present a new theory to re-examine the immobilization technique of dye doped sol-gel films, define the strength and types of possible bonds between the immobilized molecule and sol-gel glass, and show that the immobilized molecule is not free inside the pores as was previously thought. Immobilizing three different pH sensitive dyes with different size and functional groups inside the same sol-gel films revealed important information about the nature of the interaction between the doped molecule and the sol-gel matrix. The samples were characterized by means of ultraviolet-visible spectrophotometer (UV-VIS), thermal gravimetric analysis (TGA), mercury porosimetry (MP), nuclear magnetic resonance spectroscopy ((29)Si NMR) and field-emission environmental scanning electron microscopy (ESEM-FEG). It was found that the doped molecule itself has a great effect on the strength and types of the bonds. A number of factors were identified, such as number and types of the functional groups, overall charge, size, pK(a) and number of the silanol groups which surround the immobilized molecule. These results were confirmed by the successful immobilization of bromocresol green (BCG) after a completely polymerized sol-gel was made. The sol-gel consisted of 50% tetraethoxysilane (TEOS) and 50% methyltriethoxysilane (MTEOS) (w/w). Moreover, the effect of the immobilized molecule on the structure of the sol-gel was studied by means of a leaky waveguide (LW) mode for doped films made before and after polymerization of the sol-gel.