Demirin yapay deniz suyu içindeki korozyonu üzerine Sülfür(S) ve Amonyum(NH+4) iyonlarının etkileri

TEZ619Tez (Doktora) -- Çukurova Üniversitesi, Adana, 1989.Kaynakça (s. 87-89) var.v, 91 s. ; 30 cm.

Hydrogen evolution at platinum (Pt) and at platinized platinum (Ptz) cathodes

In this study, the cathodic behaviours of bright platinum (Pt) and at platinized platinum (Ptz) on the platinum anode were investigated in a 1M $Na_2SO_4$electrolyte (pH, from 2 to 8) by means of electrolysis. The theoretical ($\Delta$Erev) and experimental ($\Delta E_{exp}$) discharge potentials and the cathodic overpotentials ($\eta$c) of the systems were determined. The amounts of hydrogen gas produced at different times on the cathodes at a constant potential (5V) were measured and the hydrogen yield was calculated. The resulting scheme has been very helpful to obtain wodified electrocatalytic coating and electrode structures at Ptz cathode, able to operate for long time with good and stable performances.In this study, the cathodic behaviours of bright platinum (Pt) and at platinized platinum (Ptz) on the platinum anode were investigated in a 1M $Na_2SO_4$electrolyte (pH, from 2 to 8) by means of electrolysis. The theoretical ($\Delta$Erev) and experimental ($\Delta E_{exp}$) discharge potentials and the cathodic overpotentials ($\eta$c) of the systems were determined. The amounts of hydrogen gas produced at different times on the cathodes at a constant potential (5V) were measured and the hydrogen yield was calculated. The resulting scheme has been very helpful to obtain wodified electrocatalytic coating and electrode structures at Ptz cathode, able to operate for long time with good and stable performances

İskenderun Körfezindeki kirleticilerin derişimleri ve yapı malzemelerine etkisi /Birgül Yazıcı.

TEZ174Tez (Yüksek Lisans) -- Çukurova Üniversitesi, Adana, 1984.Kaynakça (s. ıx-xıı) var.49, [6] s, ; 29 cm.

Electrooxidation of linear alkyl benzene sulfonate (LAS) on Pt electrodes

The electrochemical behaviour of linear alklybenzene sulfonate (LAS) on Pt electrodes was investigated in 0.05M $Na_2SO_4$ and in 0.1M NaCl at pH=8 by the potentiokinetic method and by electrolysis. The anodic and cathodic semilogarithmic current-potential curves were obtained between -1.6V - +1.6V. The experimental discharge potentials were determined by means of current-potential-curves obtained by electrolysis between 0-3V. The percentages of surface active material remaining in the solution after specified periods (0-6hrs) were determined for different initial concentrations of LAS (30, 150, 300 ppm) by using a potentiostat at +1.6V and by applying a potential of 20V via a direct current source. The concentrations of LAS in the solution were determined with a UV spectrophotometer. The results indicate that when a potential of 20V is applied on the electrodes the concentrations of surface active materials (LAS) decrease by 40-50% at the end of 6 hours in 0.05M $Na_2SO_4$ solution.The electrochemical behaviour of linear alklybenzene sulfonate (LAS) on Pt electrodes was investigated in 0.05M $Na_2SO_4$ and in 0.1M NaCl at pH=8 by the potentiokinetic method and by electrolysis. The anodic and cathodic semilogarithmic current-potential curves were obtained between -1.6V - +1.6V. The experimental discharge potentials were determined by means of current-potential-curves obtained by electrolysis between 0-3V. The percentages of surface active material remaining in the solution after specified periods (0-6hrs) were determined for different initial concentrations of LAS (30, 150, 300 ppm) by using a potentiostat at +1.6V and by applying a potential of 20V via a direct current source. The concentrations of LAS in the solution were determined with a UV spectrophotometer. The results indicate that when a potential of 20V is applied on the electrodes the concentrations of surface active materials (LAS) decrease by 40-50% at the end of 6 hours in 0.05M $Na_2SO_4$ solution

The effect of nicotinamide on iron corrosion in chloride solutions

The use of nicotinamide ``3-pyridineamide'' as an iron corrosion inhibitor was tested in aerated aqueous solutions of NaCl and $Na_2SO_4$ for different pH values. Polarization resistance $(R_p)$ measurements, polarization curves and AC impedance spectroscopy techniques were used to obtain experimental data. Nicotinamide (ND) was found to exhibit a cationic-type inhibitor behaviour in acidic solution of NaCl (pH 3) and also a weak inhibitory effect in acidic sulphate solution (pH 3). The impedance spectra at open circuit potential showed that the corrosion process of the metal was characterized by two distinguishable capacitive loops. The charge transfer resistance $(R_t)$ and the polarization resistance $(R_p)$ values calculated from the interpretation of Nyquist plots were in agreement with the results of the other techniques.The use of nicotinamide ``3-pyridineamide'' as an iron corrosion inhibitor was tested in aerated aqueous solutions of NaCl and $Na_2SO_4$ for different pH values. Polarization resistance $(R_p)$ measurements, polarization curves and AC impedance spectroscopy techniques were used to obtain experimental data. Nicotinamide (ND) was found to exhibit a cationic-type inhibitor behaviour in acidic solution of NaCl (pH 3) and also a weak inhibitory effect in acidic sulphate solution (pH 3). The impedance spectra at open circuit potential showed that the corrosion process of the metal was characterized by two distinguishable capacitive loops. The charge transfer resistance $(R_t)$ and the polarization resistance $(R_p)$ values calculated from the interpretation of Nyquist plots were in agreement with the results of the other techniques

Zinc modified polyaniline coating for mild steel protection

Polyaniline (PANi) coating (~1.1 µm thick) was synthesized electrochemically on mild steel (MS), from 0.1 M aniline containing aqueous oxalic acid solution and using cyclic voltammetry technique. Then, this PANi coating was modified with the deposition of zinc particles from 0.2 M ZnSO4 solution. The electrodeposition of zinc particles (approximately 1 mg/cm2) has been achieved, at the constant potential value of -1.20 V. The corrosion performance of zinc modified PANi coating has been investigated in 3.5% NaCl solution, by using electrochemical impedance spectroscopy and anodic polarisation curves. Also, the corrosion behaviour of single PANi coated MS and bare zinc (Zn) samples have been investigated, for comparison. It was shown that zinc deposition lowered the permeability of polymer film significantly. Also, the zinc particles provided important cathodic protection to MS for considerably long immersion period. The polymer film provided the electrical conductivity between the substrate and zinc particles, this enhanced the cathodic protection efficiency. The corrosion of zinc particles led to formation of very stable corrosion products which improved the barrier property of zinc modified PANi coating system, further. © 2005 Elsevier B.V. All rights reserved

Polyindole top coat on TiO2 sol–gel films for corrosion protection of steel

The protection efficiency of polyindole film on stainless steel was enhanced via titanium dioxide precoating. The characterization of coatings was achieved by nuclear magnetic resonance and Fourier-transform infrared spectra. The surface morphology of electrodes was monitored with scanning electron microscope. The corrosion performance was investigated in 3.5% NaCl solution by electrochemical impedance spectroscopy and potentiodynamic measurements. The quantum calculations were employed, and theoretical parameters were determined. Results showed that the correlation between experimental and theoretical parameters. The high protection efficiency was observed against corrosion on the steel surface via forming a protective polyindole top coated titanium dioxide film.This study has been financially supported by the Cukurova University research fund. The authors are greatly thankful to Çukurova University Research fund. The authors also thank to The Scientific and Technical Research Council of Turkey (TUBITAK

The electrochemical synthesis and corrosion behaviour of TiO2/poly(indole-co-aniline) multilayer coating: Experimental and theoretical approach

The aim of this study was to protect stainless steel against corrosion via poly (indole-co-aniline) with the help of titanium dioxide pre-coating. Different monomer ratios (1:1 and 1:9) were applied in order to determine the suitable chain composition to synthesize the copolymer in lithium perchlorate containing acetonitrile. The structures, morphologies, electrochemical properties and corrosion resistances of the mono and multi-layer coatings were investigated by Fourier-transform infrared spectra, scanning electron microscope, energy dispersive X-ray spectrometer, electrochemical impedance spectroscopy and anodic polarization. Furthermore the geometric structure and electronic properties of indole, aniline, and indole-co-aniline (dimmer) molecules have been investigated by quantum calculations. The results indicated that corrosion protection of copolymers was increased via titanium dioxide pre-coating. The 1:1 copolymer coating showed better corrosion prevention than 1:9 coating. The correlation was determined between experimental and theoretical parameters

Yumuşak Çeliğin Asidik Ort. KorozyonuÜzerine 2-Amino-6-Metil Piridinin İnhibisyon Etkisi

Ett barn kräver mer stöd och förståelse för vad som kommer att ske. En interhospital överföring innebär ett byte av miljö vilket kan upplevas hotfullt för barnet. Miljön är oförutsägbar och vårdpersonal kan uppleva ensamhet om känslan av gemenskap uteblir. Här finns ett behov av trygghet som kan uppnås genom samverkan med kollegor, planering och kunskap. Syftet var att undersöka anestesisjuksköterskans upplevelse av att vårda barn under interhospital överföring. Studien är gjord med kvalitativ forskningsmetod och data är analyserat med kvalitativ innehållsanalys. Sex anestesisjuksköterskor med erfarenhet av interhospital överföring av barn har intervjuats i öppna intervjuer. Semistrukturerade frågeställningar har använts. Det upplevs att en extra skärpa krävs vid vård av barn under interhospital överföring då barn inte har lika mycket reserver som vuxna och läkemedelsdoser samt vitala parametrar varierar med barnets vikt och ålder. Vikten av att vara förberedd på det oförberedda samt att noga planera inför resan framkommer. Erfarenhet påverkar vårdarens förmåga att delegera arbete och speglar hur vårdaren löser olika situationer som upp kommer.Det påverkar även anestesisjuksköterskan syn på ambulanspersonalen. Erfarenhet av att vårda barn ger deltagarna en stark känsla av trygghet. Vårdpersonalen har ett behov av trygghet för att kunna ge en godvård. Det skiljer sig mellan deltagarna beroende på om de upplever en gemenskap med den andra vårdpersonalen under transporten. Gemenskap bildar en trygghet i vårdandet men anestesisjuksköterskan kan fortfarande uppleva en känsla av utsatthet eller ensamhet i vårdandet av ett barn. Föräldrar är barnens trygghet