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The purpose of this paper is to report the studies on the corrosion inhibition property of 4-amino-5-phenyl-4H-1,2,4-triazole-3-thiol (APTT) for the corrosion of 6061 Al-15 vol. pct. SiC(p) composite.

The corrosion behavior of 6061 Al-15 vol. pct. SiC(p) composite was studied at different temperatures in 0.5-M sodium hydroxide (NaOH) solution in the presence of APTT by potentiodynamic polarization (PDP) and electrochemical impedance spectroscopic techniques. The effect of inhibitor concentration and temperature on the inhibitor effect of APTT was studied. The surface morphology of the metal surface was investigated by scanning electron microscopy. The activation parameters for the corrosion of the composite and base alloy, as well as the thermodynamic parameters for the adsorption of APTT on the composite and alloy surfaces, were calculated.

The inhibition efficiency of APTT increases with the increase in the concentration of the inhibitor and decreases with the increase in temperature. The adsorption of APTT on the composite was found to be through physisorption, obeying Langmuir’s adsorption isotherm. APTT acts as a mixed inhibitor with predominant cathodic action on the composite.

APTT can be used as an inhibitor for the corrosion of 6061 Al-15 vol. pct. SiC(p) composite in the NaOH medium.

This paper provides information regarding the corrosion inhibition property of APTT on 6061 Al-15 vol. pct. SiC(p) composite. An attempt was made to explain the mechanism of the inhibition action by APTT.

The purpose of this paper is to compare the effect of rust inhibitors and surface strengthening materials on the service life of RC structures in tropical marine environments and ultimately to provide basis and recommendations for the durability design of reinforced concrete (RC) structures.

Slag concrete specimens mixed with four kinds of rust inhibitors and coated with four kinds of surface strengthening materials were corroded by seawater exposure for 365 days, and the key parameters of chloride ion diffusion were obtained by testing. Then a new service life prediction model, based on the modified model for chloride ion diffusion and reliability theory, was applied to analyze the effect of rust inhibitors and surface strengthening materials on the service life of RC structures in tropical marine environments.

Rust inhibitors and surface strengthening materials can effectively extend the service life of RC structures through different effects on chloride ion diffusion behavior. The effects of rust inhibitors and surface strengthening materials on the service life extension of RC structures adhered to the following trend: silane material > cement-based permeable crystalline waterproof material > hydrophobic plug compound > spray polyurea elastomer > water-based permeable crystalline waterproof material > calcium nitrite > preservative > amino-alcohol composite.

Using a new method for predicting the service life of RC structures, the attenuation law of the service life of RC structures under the action of rust inhibitors and surface strengthening materials in tropical marine environments is obtained.

Unleavened bread (chapatti and roti) is the staple diet of people in the Indo‐Pak region, utilizing almost 90 percent of the wheat produced in the region. To improve the nutrition of chapattis, normally legume flour is used in the region. The purpose of the current study is to assess the nutritional quality and safety of chapattis supplemented with soy flour.

Wheat and soybean were procured and soy flour was prepared. Trypsin inhibitor contents and mineral contents of different flour and chapattis prepared were determined. Chapattis were prepared from different flour blends and whole wheat flour. To assess the quality and acceptability, the chapattis were presented to a panel of judges and the sensory evaluation was carried out for color, taste, aroma, chew ability, folding ability and overall acceptability characteristics. The data obtained for each parameter were subjected to statistical analysis to determine the level of significance.

The phytic acid and trypsin content were higher in un‐autoclaved soy flour supplement composite flour. The defattening of soy flour also increases the level of these anti‐nutrients in chapattis. The phytate and trypsin content of composite flour decreased as a result of baking. The protein, fiber and ash contents of composite flour increased while moisture content and nitrogen free extracts (NFE) decreased by the addition of soy flour. Mineral contents of chapattis except Mn increased by the incorporation of soy flour. The chapattis were found acceptable by the panel of judges at 10 percent replacement level of whole wheat flour by soy flour.

The results of the study indicate that 10 percent supplementation of soy flour in wheat flour was found acceptable by consumers as it did not affect the sensory attribute. For improved nutrition and to combat protein energy malnutrition, chapattis flour can be supplemented with soy flour.

The soy supplementation of wheat flour will improve the nutritional quality of the chapatti flour as soy flour is rich in high‐quality protein and mineral. The anti‐nutritional can be minimized or inactivated by autoclaving the soybean.

This paper aims to investigate the inhibition effect of sodium silicate (SS), sodium alginate (SA) and sodium tungstate (ST) on the corrosion behavior of AZ91D magnesium alloy in 3.5 per cent NaCl solution through polarization curve test at room temperature, electrochemical impedance spectroscopy and weight loss measurement.

The influence of SA concentration on the inhibition efficiency of the corrosion inhibitor was mainly analyzed. The corrosion morphology and inhibition mechanism of the samples were also analyzed with scanning electron microscopy and energy-dispersive spectroscopy.

The results show that with the increase of SA concentration, the corrosion inhibition first increases and then decreases. When SA concentration is 0.03 mol/L, the inhibition efficiency is the highest, reaching 98 per cent. The adsorption film formed by SA and other deposition films produce a synergistic effect on the improvement of corrosion resistance of AZ91D magnesium alloy.

The adsorption film formed by SA with other deposition films produces a synergistic effect on the improvement of corrosion resistance of AZ91D magnesium alloy. With the increase of SA concentration, the corrosion inhibition first increases and then decreases. When the concentrations of SA, SS and ST are 0.03 mol/L, 0.015 mol/L and 0.02 mol/L, respectively, the inhibition efficiency of the inhibitor is the highest, reaching 98 per cent.

The purpose of this paper is to focus on the performance analysis of Polyvinylpyrrolidone (PVP) – Chitosan composite dye transfer inhibitor (DTI) for household laundry. The developed composite DTI is tested against different commercial dyes and detergent powders normally used in the household laundry for its performance.

The DTI article is tested for its performance against five commercial dyes and five commercial detergent compositions. The dye re-deposition behaviour of the control fabric was measured in terms of the colour difference (ΔE) values. The influence of PVP on the washing efficiency of detergent was evaluated against tea, coffee and juice stains.

The results showed that there is an excellent performance of the developed product noted in terms of DTI performance against reactive, basic and sulfur dyes. The DTI product showed a significantly (p<0.05) less performance against acid and direct dyes. There is no significant differences noted in the stain removal efficiency of the detergent in the presence of PVP in the wash liquor (p>0.05).

The usage of DTI polymer in the household laundry has no significant influence on the detergents performance in terms of stain removing efficiency. The DTI polymer’s function in the wash liquor depends up on the type of polymer used, as they are sensitive to the type of detergent compositions used and the type of dyes bleeds in the wash liquor.

This paper aims to identify an inhibitor to protect rebar corrosion in concrete.

The authors use the simple method of polarization and calculate the change in open-circuit potential and corrosion current density.

Sodium molybdate is an efficient inhibitor compared with sodium tungstate for rebar corrosion in concrete.

This paper has limitation of 0.0001 M concentration of inhibitors for 400 days of exposure in 3.5 per cent sodium chloride solution.

The research focused on the concentration of both inhibitors in the range from 0.1 to 0.0001 M, which resulted in greater structural protection from corrosion in adverse conditions, such as coastal areas.

The purpose of this study is to investigate the inhibition efficiency and mechanism of a specific carboxylate corrosion inhibitor which consists of benzoic acid and dimethylethanolamine on steel surface.

The performance of carbon steel influenced by this organic inhibitor under different concentration of Cl⁻ and immersion time was studied by linear polarization resistance and electrochemical impedance spectroscopy in a simulated concrete pore (SCP) solution. The surface morphology and composition of steel was also analyzed by optical microscopy, SEM and EDS to investigate the effect of inhibitor on the pattern of the steel surface after long-term immersion.

Carboxylate of benzoic acid and dimethylethanolamine can increase the chloride threshold level and decrease the corrosion area of carbon steel in SCP solution with 0.6 mol/L Cl⁻ even after 120 days exposure. The inhibition mechanism of inhibitor lies in quick adsorption and buffering effect at initial time then formed deposited layer on steel surface after long-term immersion in chloride-rich environment.

It demonstrated that the carboxylate corrosion inhibitor not only can improve the chloride threshold level for carbon steel but also effectively decrease the corrosion rate even in chloride-rich SCP solution after long-term immersion, which is different form the conventional amino alcohol.

The purpose of this study is to investigate the presence of silicon dioxide (SiO₂) nanoparticles in o-toluidine monomer as a reactant and ammonium persulfate as an oxidant to obtain the poly(o-toluidine) (POT)/SiO₂ nanocomposites by oxidative polymerization method.

Fourier transformation infrared spectroscopy, X-ray diffraction and field emission scanning electron microscopy were used to characterize the structural properties of the composite. POT/SiO₂ nanocomposites were mixed with acrylic resin through a solution mixing method and the composites were coated onto the surface of mild steel. Electrochemical measurements were used to determine the corrosion protection efficiency (P.E.%) of polymer composite coatings using 3.5% NaCl solution as corrosion environment.

The results obtained reveals that the POT/SiO₂/acrylic resin composite coatings have got higher corrosion P.E.% than that of POT/acrylic resin coatings.

The formation of uniformly passive layer in the POT/SiO₂ composite was used to enhance the P.E.% on mild steel surface. The POT/SiO₂/acrylic resin nanocomposites showed effective anticorrosive behavior on mild steel in 3.5% NaCl solution.

This paper aims to introduce a method to reduce corrosion caused by acidic-oxidized polymer degradant through subsection injection with different inhibitor.

This paper introduced a method to reduce corrosion caused by acidic-oxidized polymer degradant through subsection injection with different inhibitor.

The experimental results indicated that the influence of pre-corrosion status on corrosion rate and effectiveness of corrosion inhibitor are significant. The corrosion inhibitors in both injection stage inhibited the corrosion process by preventing the contact of corrosive medium and steel surface through formation of a protective film on the surface of N80 steel. The corrosion rate of polymer degradant can be reduced to 0.63 g/m 2 h through subsection injection with different inhibitor.

This result will increase the production of polymer injection plugging wells through expanding the application of acidic-oxidized polymer degradant.

This paper aims to present experimental results related to the performance of cactus mucilage (CM) and brown seaweed extracts (SEs) to inhibit reinforcing steel bar (rebar) corrosion in saturated calcium hydroxide alkaline solutions (pH = 12.5).

Electrochemical cells were prepared using CM solutions at 0.5, 1 and 1.38 per cent concentration (w/v), SE solutions at 0.5, 1, 1.38, 2 and 3 per cent concentration (w/v), sodium alginate at 1 per cent concentration (w/v) and calcium nitrite at 11.3 per cent (v/v). Each cell contained six deformed reinforcing steel bars of 9.5 mm nominal diameter. The experiments were performed at 23 ± 2°C in two stages. The first stage was aimed at stabilizing the rebar until passivation was reached. The second stage included adding NaCl in six steps from 0.5 to 16 g/L. Half-cell potential, linear polarization resistance and electrochemical impedance spectroscopy measurements were monitored during both stages.

The electrochemical test results indicated that both additions reduce the corrosion rate of rebars and pitting in an alkaline media with chloride ions (16 g/L NaCl). Electrochemical impedance spectroscopy results for rebars in natural-added solutions showed higher charge transfer resistance and double layer capacitance values, indicative of the formation of a second interface between the rebar and the electrolyte.

The information obtained was for alkaline solutions only. Further investigation is performed using concrete as the alkaline electrolyte.

CM and SE may be suitable low-cost corrosion inhibitors for steel in concrete.

The use of botanical or algae products for this application will encourage people to consider its production for this particular application. Also, the possible harvest in an environmental friendly way will diminish in the future the use of biohazards and toxic inhibitors.

This investigation is a continuation of a one presented in 2007, which uses only nopal mucilage. This new investigation corroborates what was concluded in the early investigation and incorporates a new natural by product, algae, as a possible corrosion inhibitor product.