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An environmental friendly route to synthesize titanium dioxide nanotube powder is developed using a semi‐batch reactor set‐up that combines both anodization and the plasma treatment of water. A constant supply of the reactive plasma species, such as nitrate and hydrogen peroxide, in the semi‐batch reactor facilitates the formation of titanium dioxide nanotubes during the anodization of titanium. The results are compared against a conventional batch reactor set‐up that uses the same plasma‐treated water constantly during the anodization, which impacts the quality of the nanotubes produced. The semi‐batch reactor set‐up resulted in the formation of powders of titanium dioxide nanotubes with better physical and chemical qualities than those produced in the batch set‐up. [ABSTRACT FROM AUTHOR]

An environmentally friendly electrolyte for the synthesis of titanium dioxide nanotubes by anodization is presented. Plasma treatment of de-ionized water produces some important reactive species such as nitrate and hydrogen peroxide. This plasma-treated water serves as an efficient electrolyte in the formation of titanium dioxide nanotubes during anodization. In order to further understand the roles of nitrate and hydrogen peroxide, titanium foil was anodized in plasma treated water containing nitrate or/and hydrogen peroxide as well as in its equivalent solution made by adding nitric acid and/or hydrogen peroxide to water. It was found that the plasma treated water containing both nitrate and hydrogen peroxide produced more uniform arrays of highly crystalline titanium dioxide nanotubes than produced in the aqueous solution made with nitric acid and hydrogen peroxide. [ABSTRACT FROM AUTHOR]

Treatment of milk with argon gas plasma was investigated for its ability to kill bacteria and increase shelf life and compared with commercially pasteurized milk. The discharge was generated by a nanosecond pulse generator using the needle point-to-plate electrode. The total bacterial count of 6.8 log CFU/mL in raw milk was reduced to 1.9 log CFU/mL after 2 min of plasma treatment and 2.2 log CFU/mL after 30 min of pasteurization. The plasma treated milk stored at 4 °C showed no significant changes in the bacterial count for 6 weeks while the bacterial counts in pasteurized milk were significantly increased from 2.2 to 4.2 log CFU/mL after 2 weeks. These results demonstrated plasma treatment as an alternative way to decontaminate and increase shelf life of milk. [ABSTRACT FROM AUTHOR]

A functionalization of microstructures of polyhedral oligomeric silsesquioxane (POSS) to obtain substrates contain N-moieties, with a probable high selectivity of primary mines is demonstrated for the first time in a low pressure plasma process through a sequential continuous wave plus pulsed mode (CW + P). Selective grafting of N-moieties was performed across octa-methyl POSS micro-powder by substituting hydrogen atoms of the terminal methyl groups during nitrogen/hydrogen (N2/H2) gases plasma. As opposed to wet chemical functionalization approaches, the plasma method does not require reactive chemicals and is environmentally friendly. The results demonstrate the efficiency of the treatment (N/Si) reaches 7.1% with an indication of high NH2 selectivity (NH2/N). The amount of primary amines is determined from XPS data after 4-(trifluoromethyl) benzaldehyde (TFBA) chemical derivatization. [ABSTRACT FROM AUTHOR]

Plasma-treated water is used as an environmentally friendly electrolyte for the synthesis of nanoporous titanium dioxide nanotubes by anodization of titanium. The possible mechanism of nanotube formation in the process is studied. The reactive species hydrogen peroxide and nitrate can be selectively produced in a gas bubble discharge in liquid using argon plasma or air plasma, respectively. It is observed that hydrogen peroxide enhances only the formation of an oxide layer, while nitrate forms pores on this oxide layer. It is proposed that the nitrate determines the formation of nanoporous nanotubes, while hydrogen peroxide enhances the oxidation. [ABSTRACT FROM AUTHOR]

A plasma gas bubble-in-liquid method for high production of selectable reactive species using a nanosecond pulse generator has been developed. The gas of choice is fed through a hollow needle in a point-to-plate bubble discharge, enabling improved selection of reactive species. The increased interface reactions, between the gas-plasma and water through bubbles, give higher productivity. H2O2 was the predominant species produced using Ar plasma, while predominantly [ABSTRACT FROM AUTHOR]

Nitrogen doped SnO2 polycrystalline nanostructures were produced from commercial SnO powders in a new system that combines a low-temperature plasma with heating. The method has the potential to improve the initial efficiency and the cycling performance of SnO2 anodes in Li-ion batteries. With this system, the temperature of the SnO to SnO2 conversion was lowered from 430 to 320 °C, up to 5 at% of doped nitrogen was detected and a nano-scale polycrystalline structure was observed in the product. Combining heat and low-pressure plasma is a promising approach for the production and treatment of enhanced energy storage materials. [ABSTRACT FROM AUTHOR]

A three-step plasma treatment-activation, functionalization and polymerization-has been used to deposit a thin plasma polymer with amine groups on carbon fibres (CFs). This plasma polymer has strong adhesion to the CF surface and the amine groups enable strong bonding to a matrix. The CFs were first treated by Ar plasma to activate and clean the surface, followed by O2 plasma to incorporate oxygen-containing functional groups, and finally a heptylamine thin film was deposited using combined continuous wave and pulsed plasma polymerization. Strong adhesion between the plasma polymer and the CF was observed. The fibre strength was not affected by the treatment. [ABSTRACT FROM AUTHOR]

A systematic study was conducted using argon, oxygen, and nitrogen plasma to improve the adhesion of polypyrrole coating to polyester (PET) fabric for improving conductivity and to understand the mechanisms involved. PET thin film was used as a reference sample. The changes in wettability, surface chemistry and morphology were studied by water contact angle, X-ray photoelectron spectroscopy, and atomic force and scanning electron microscopy. It was found that both the highest conductivity and the strongest interfacial bonding were achieved by oxygen plasma treatment. The increase in hydrophilicity, surface functionalization, and suitable nano-scale roughness gave improved adhesion. [ABSTRACT FROM AUTHOR]

Improved methods of functionalizing the surfaces of multi-walled carbon nanotubes (MWCNTs) have been investigated. It is shown that a level of primary amines of 2.3%, higher than previously reported for any nitrogen-containing gas plasma treatment, can be achieved using a mixture of N2 and H2, which is preferable to using NH3. Even higher levels (3.5%) of primary amines can be achieved by coating the MWCNTs with a thin layer of plasma polymerized heptylamine. In both cases, the highest levels were achieved using a combined continuous plus pulsed plasma mode which was superior to either continuous wave or pulsed wave alone. The integrity of the MWCNT structure is maintained by the plasma treatments, and the functionalized surface improves the dispersion of the MWCNTs and their interfacial bonding with epoxy, giving superior nanoindentation performance of the composites. [ABSTRACT FROM AUTHOR]

A novel bio-interface, produced by a combined plasma polymerization mode on a titanium (Ti) surface, was shown to enhance osteoblast growth and reduce fibroblast cell growth. This new method can securely attach a tailored interface to difficult materials such as Ti or ceramics. Here a more stable and higher density of NH2 functional groups is able to withstand sterilization in ethanol. The biocompatibility, in terms of cell attachment and actin cytoskeleton development, was markedly improved in vitro, compared with untreated Ti surfaces and samples treated by other plasma modes. It gave a boosted (approximately six times higher) cellular response of osteoblasts in their initial adhesion stage. These factors should increase the formation of new bone around implants (reducing healing time), promoting osseointegration and thereby increasing implantation success rates. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part A:, 2011. [ABSTRACT FROM AUTHOR]

BACK Cover: Plasma treated water has been shown to be a superior electrolyte, compared to water prepared by adding the equivalent chemicals, in producing good quality TiO2 nanotubes during anodization of titanium. The nitrates, hydrogen peroxide and the other reactive plasma species in plasma treated water acted in synergy to produce good quality TiO2 nanotubes. Further details can be found in the article by Arun T. Ambujakshan et al. on page 1700054. [ABSTRACT FROM AUTHOR]

Front Cover: Argon plasma is generated in gas bubbles inside milk to decontaminate and extend shelf life. Plasma treatment effectively reduced bacteria and significantly increased shelf life to six weeks, while commercially pasteurized milk deteriorated after two weeks. These improvements were attributed to the plasma reactive species which interacted, through the interface, with bacteria present in the water phase of milk. Further details can be found in the article by Sri B. Ponraj et al. on page 1600242. [ABSTRACT FROM AUTHOR]

Front Cover: The reactive plasma species nitrate (NO3‐) and hydrogen peroxide (H2O2) were produced in high selectivity in water using air and argon, respectively, in a needle and plate electrode assembly. The plasma treated water was used as an efficient and environmentally friendly electrolyte for anodizing titanium metal. The NO3‐ from air plasma is the key factor in the formation of TiO2 nanotubes and the H2O2 from the argon plasma assists the oxidation process. Further details can be found in the article by A. T. Ambujakshan et al. on page 1600219. [ABSTRACT FROM AUTHOR]

Front Cover: The selected gas is injected through a hollow needle at a gap to a second, mesh electrode. Both electrodes are placed within the liquid. A plasma is generated inside the bubbles. The increased interface reactions between the gas‐plasma and water gives fast mass transport enabling higher production of reactive species. Argon plasma generates hydrogen peroxide (H2O2) with nearly 100% selectivity, while using air leads to high concentrations of NO3− and NO2. Further details can be found in the article by Xiujuan J. Dai et al. on page 306. [ABSTRACT FROM AUTHOR]

Back Cover: The combination of cold plasma with thermal treatment enables doping and changed growth of semiconductors that cannot be achieved by either treatment alone. The combination applied to commercial SnO powder produced SnO2 with a nano‐scale polycrystalline structure and controllable nitrogen doping of up to 5 at. %. This product has potential as an improved anode material for Li‐ion batteries. Further details can be found in the article Xiujuan J. Dai et al. on page 897. [ABSTRACT FROM AUTHOR]