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In this research, the microstructure and corrosion behavior of Ni-Mo alloy coatings obtained from a citrate bath solution containing sodium dodecyl sulfate (SDS) as an anionic surfactant, and cetyltrimethylammonium bromide (CTAB) as a cationic surfactant, have been investigated.

For this purpose, the Cathodic polarization curves were plotted using a potentiostat/galvanostat set. Scanning electron microscopy and energy dispersive spectroscopy were, respectively, used to investigate the morphology and chemical composition of the coatings.

The results of the corrosion test showed that the corrosion resistance of the coatings obtained from electroplating bath only containing CTAB surfactant was deteriorated. On the other hand, SDS anionic surfactant positively affected on the corrosion resistance of the coatings when it was added to the electroplating bath.

For this purpose, the Cathodic polarization curves were plotted using a potentiostat/galvanostat set. Scanning electron microscopy and energy dispersive spectroscopy were respectively used to investigate the morphology and chemical composition of the coatings.

The purpose of this paper is to investigate the inhibiting properties of six quaternary ammonium salts, three cationic surfactants and two non‐ionic surfactants in 2 M KOH. An attempt also was made to correlate some molecular parameters of these compounds with their corrosion inhibitor efficiency.

The inhibition efficiencies of quaternary ammonium salts, cationic surfactants and non‐ionic surfactants on the corrosion of zinc in 2 M KOH solution were investigated by potentiodynamic polarisation, electrochemical impedance spectroscopy and linear polarisation methods.

Inhibition efficiencies of quaternary ammonium salts were found to be due to physical absorption on the cathodic sides of zinc electrode and dependence of inhibition efficiencies on substituents were found. Physical adsorption of cationic surfactants on zinc electrode slowed down both anodic and cathodic reactions; thus they were found to be mixed type inhibitors. On the other hand, inhibition behaviour of non‐ionic surfactants was found to be due to adsorption on zinc via polar groups. It was found that non‐ionic surfactants behaved as mixed type inhibitors.

Clarifies the role of molecular structure and substituents on the inhibition efficiency of surfactants and quaternary ammonium compounds on the corrosion of zinc in alkaline media.

At present, the conventional method of preparing cationic fluorinated acrylic latex is to emulsify copolymerised monomers with cationic surfactants. However, there has been a wide concern about using Gemini surfactants to prepare cationic polymer latex to improve its properties. The purpose of this paper was to focus on the synthesis of novel self-crosslinked cationic fluorinated acrylic latex (SCFAL), during which the copolymerised monomers were initiated with a water soluble azo initiator and emulsified with mixed surfactants of Gemini emulsifier and alkyl polyglycoside (APG).

The novel SCFAL was prepared successfully by the semi-continuous seeded emulsion polymerisation of butyl acrylate, methyl methacrylate, hexafluorobutyl methacrylate (HFMA) and hydroxy propyl methacrylate (HPMA) in aqueous medium.

The conversion is the maximum and the coagulation percentage the minimum when the amounts of emulsifier and initiator are 8 and 0.6 per cent, respectively. The average particle size of the latex is significantly reduced with the increase of the amount of emulsifiers used. However, the average particle size of the latex is increased with the increase of the amount of HPMA. The particle size of the latex is of a unimodal distribution, which means that the particle size was reasonably uniform. Contact angle is increased with the increase of the amount of the HFMA.

The novel SCFAL can be widely used as significant components in the field of coatings, leather, textile, paper, adhesives and so on.

SCFAL, which was emulsified with novel mixed surfactants of Gemini surfactant and APG, has been prepared successfully. Influences of amount of initiator, emulsifier, HPMA and HFMA on emulsion polymerisation and/or properties of novel latex are investigated in detail.

As an example of structure-efficiency relationship study, this paper aims to evaluate the corrosion inhibition effect of two cationic surfactants, cetyl-trimethyl ammonium chloride (CTAC) and cetyl-dimethyl-hydroxyethyl ammonium chloride (CDHAC), and to discuss the effect of structure on the performance by thermodynamics methods.

The effect of the two cationic surfactants, CTAC and CDHAC, on the corrosion of the mild steel in HCl solution was investigated by using weight loss measurements, and the activation energies of CTAC and CDHAC involved in the corrosion inhibition were calculated and discussed.

The weight loss measurements showed that the corrosion inhibition efficiency of CDHAC was higher than that of CTAC in any case. The effects of the structure on performance were discussed, and the following data are available from the results, all of ΔS are positive, the values of ΔG are both close to −40 kJ·mol-1 and the values of ΔH are 10.960 and 36.996 kJ·mol-1, which indicate that the surfactant molecules are spontaneously adsorbed on the surface of the steel surface, and the adsorption on the steel plate is endothermic chemical adsorption.

The available data show that most organic inhibitors undergo physisorption on the metal surface, while in the presence of non-bonded and p-electrons, the inhibitor molecules may undergo chemisorption. This work showed that the two surfactant molecules are spontaneously adsorbed on the surface of the steel surface, and the adsorption on the steel plate is endothermic chemical adsorption.

Surface active agents are widely used to impart special characteristics to surface coatings formulations. The large variety of “surfactants” now commercially available may leave the coating technologist with the problem of how to choose the best for his particular system. It is hoped that by outlining the relationships between molecular structure and surfactant properties a reasonable working basis for selection of surfactants may be gained.

This paper presents the results of laboratory experiments that investigate the removal of volatile organic compounds from saturated soils through the use of air sparging. Three series of experiments were performed in a column test apparatus using two different soils to represent actual field conditions, namely, a fine gravel and a medium‐to‐fine Ottawa sand (both obtained from sources near Chicago, Illinois, USA) contaminated with toluene, a major constituent of petroleum products. The results showed that toluene was removed from gravel very efficiently using air sparging; complete removal was achieved using a variety of air flow rates. However the toluene removal rates in tests using sand were significantly less. Even at the highest air flow rate used during testing, complete toluene removal took eight times longer than in comparable tests using gravel. With low air flow rates this was not achieved even after 17 hours of testing. It was further found that the injection of foams generated with surfactants, SDS and witconol SN70, at low air flow rates during the use of air sparging was found to accelerate the bulk removal of toluene in sand, but the use of surfactants did not facilitate the removal of residual levels of contamination.

The purpose of this paper is to enhance the understanding on the electrodeposition of various lead (Pb)‐free solder alloys, so that new studies can be carried out to solve processing issues.

The paper reviews the available reports on the electrodeposition of tin (Sn)‐based solder systems and identifies the challenges in this area.

Compositional control remains a major challenge in this area, where the achievement of desired composition for binary and ternary alloys is subjected to uncertainties. The use of chelating agents in the bath and optimization of parameters can assist the achievement of near‐desired alloy composition. Acidic plating baths are preferred due to their compatibility with photoresists but oxidation of stannous ions causes poor bath stability. Antioxidants, reducing agents and low oxygen overpotential anodes can suppress the oxidation rate and increase the lifespan of plating baths. Apart from chelating agents and antioxidants, various categories of additives can be added to improve quality of deposits. Surfactants, grain refiners and brighteners are routinely used to obtain smooth, fine‐grained and bright deposits with good thermo‐mechanical properties.

The paper provides information on the key issues in electrodeposition of Pb‐free solder alloys. Possible measures to alleviate the issues are suggested so that the electrodeposition technique can be established for mass production of a wider range of solder alloys.

Reports on tests in which barium metaborate pigment and its modified form are prepared, identified by chemical and X‐ray diffraction methods, and specified according to standard methods. Evaluates the modified barium metaborate as a new filler for paper making by carrying out two series of experiments. Details the results which showed that the efficiency of the filler retention when using modified barium metaborate was higher than that of the other two conventional fillers. Reveals that at relatively low filler addition (2–5 percentage weight), higher improvement in the strength properties can be obtained when using the modified pigment instead of titanium dioxide and kaolin, but observes the reverse (i.e. a detrimental effect) at relatively high filler addition (8–10 percentage weight). Discovers that the optical properties of the modified pigment‐loaded sheets lie between those of titanium dioxide and kaolin. Shows that blending barium metaborate with kaolin or titanium dioxide has a significant effect on strength properties rather than optical properties. Concludes that modified barium metaborate pigment can be successfully used in paper filling applications and that modified barium metaborate pigment‐kaolin blend (80/20 per cent) can be used instead of titanium dioxide as a paper filler.

The performance of a new detergent‐free dry cleaning machine has been investigated and compared to conventional machines. The new machine includes a highly efficient system for solvent purification, and effectively cleans wool, cotton and synthetic fibers without the need of detergent. Its performance is similar or in some cases better than the conventional machines, which contaminate the clothes with detergent. Since detergent is not needed and solvent is efficiently used in the new machine, environmental impacts and operation costs are reduced, and the negative side effects on the properties of clothes are eliminated.