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The purpose of this paper is to determine the optimum level of geometrical parameters such as helix angle, nose radius, rake angle and machining parameters such as cutting speed, feed rate and depth of cut to arrive minimum surface roughness and tool wear during end milling of Al 356/SiC metal matrix composites (MMCs) using high speed steel end mill cutter.

L27 Taguchi orthogonal design with six factors and three levels is employed for conducting experiments. Analysis of variance (ANOVA) is carried out using Minitab16 software to find the influence of each input parameter on output performance measure. Grey-fuzzy logic multi optimisation algorithm is used to find the optimum level of the input parameters for minimum surface roughness and tool wear simultaneously.

It is found that optimal combination of helix angle 40°, nose radius 0.8 mm, rake angle 12°, cutting speed 90 m/min, feed rate 0.04 mm/rev and depth of cut 1.5 mm have generated minimum surface roughness of 0.4063 µm and tool wear of 0.0375 mm. From ANOVA analysis, it is found that cutting speed influence is more on output performance followed by helix angle and rake angle compared with other machining and geometrical parameters.

The influence of tool geometry during end milling of MMC using Grey-fuzzy logic algorithm has not been explored previously.

The purpose of this paper is to develop a text extraction tool for scanned documents that would extract text and build the keywords corpus and key phrases corpus for the document without manual intervention.

For text extraction from scanned documents, a Web-based optical character recognition (OCR) tool was developed. OCR is a well-established technology, so to develop the OCR, Microsoft Office document imaging tools were used. To account for the commonly encountered problem of skew being introduced, a method to detect and correct the skew introduced in the scanned documents was developed and integrated with the tool. The OCR tool was customized to build keywords and key phrases corpus for every document.

The developed tool was evaluated using a 100 document corpus to test the various properties of OCR. The tool had above 99 per cent word read accuracy for text only image documents. The customization of the OCR was tested with samples of Microfiches, sample of Journal pages from back volumes and samples from newspaper clips and the results are discussed in the summary. The tool was found to be useful for text extraction and processing.

The scanned documents are converted to keywords and key phrases corpus. The tool could be used to build metadata for scanned documents without manual intervention.

The tool is used to convert unstructured data (in the form of image documents) to structured data (the document is converted into keywords, and key phrases database). In addition, the image document is converted to editable and searchable document.

The emission of SO2, a dangerous atmospheric pollutant, is the major problem with increasing the use of coal as fuel in various industries, particularly in thermal power plants. A variety of methods for minimizing the SO2 emission have been reported in the literature, among which the desulphurization of the flue gas, generated by combustion of coal receives much attention and is termed as flue gas desulphurization (FGD). FGD scrubbers have found widespread use in thermal power plants, smelters, incinerators and various refining operations. The scrubber parts must resist corrosion from solution which have a varying degree of acidity and erosion, besides containing substantial concentrations of chlorides and SO2, and the unfavourable conditions of fluctuations in temperature. The currently‐used type 316L stainless steel material in many FGD installations, were reported to have failed, due to the localized corrosion attack by the aggressiveness of the environment encountered during scrubbing of SO2. Normally, the improvement in corrosion performance of the construction materials can be achieved by:

Sulphur dioxide, a dangerous atmospheric pollutant, is a major concern with the increasing use of coal as a combustion fuel in thermal power plants. Numerous efforts were made through these years to minimize the emission of sulphur dioxide and one such effort is the desulphurization of the flue gas generated during combustion, commonly termed as flue gas desulphurization (FGD). However, the materials of construction used for FGD systems, usually of type 316L stainless steel were reported to be failed due to the localized corrosion attack by the aggressiveness of the environment, mainly of chloride, fluoride, acidity and temperature encountered during the scrubbing of SO2.

The present study aims to evaluate the performance of titanium modified austenitic stainless steels in the simulated bleaching stages, viz. washer stage, peroxide and hyprochlorite stages. Potentiodynamic anodic cyclic polarization method was adopted to determine the critical parameters such as corrosion potential, breakdown potential and pit‐protection potential.

To investigate the capability of a series of nitrogen‐based heterocyclic organic compounds in inhibiting corrosion of iron in HCl and elucidate the dominant active form of the applied compounds during the adsorption process to explore the mechanism of their action.

The tested compounds were pyrimidine containing compounds, which were selected, based on molecular structure considerations. Gravimetric method has been applied with various electrochemical techniques (polarisation resistance, polarisation curves and electrochemical impedance spectroscopy) to investigate inhibition efficiency and mechanism.

The inhibiting action of the investigated pyrimidine containing compounds depends primarily on their concentration and molecular structure. These compounds act as mixed type inhibitors and function via adsorption on the surface, which follows Frumkin adsorption isotherm. The inhibition by the tested pyrimidine derivatives could be attributed to their chemisorption on the metal surface forming donor/acceptor type of bond between the inhibitor molecules and the vacant d orbitals of the surface iron atoms. Contribution from electrostatic adsorption, via interaction between the protonated form of the inhibitor and the charged metal surface, is also possible.

The applied inhibitors were tested in the presence of chloride ions as a corrosive medium. Whether these inhibitors will function well in the presence of other ions that are typically present in natural corrosive environment is unknown.

This paper provides useful information regarding inhibition effect of pyrimidine and series of its derivatives. The outcome of this work contributes to better understanding of the mechanism of inhibition by this class of N‐based heterocyclic organic compounds.

This study aims to investigate the inhibition effect of a newly synthesized1,2,3-triazole containing a carbohydrate and imidazole substituents, namely, 1-((1-((2,2,7,7-tetramethyltetrahydro-5H-bis([1,3]dioxolo)[4,5-b:4′,5′-d]pyran-5-yl)methyl)-1H-1,2,3-triazol-4-yl)methyl)-1H-benzo[d]imidazole (TTB) on the corrosion of mild steel in aerated 1 M H₂SO₄.

The authors have used weight loss measurement, potentiodynamic polarization, electrochemical impedance spectroscopy, FT-IR studies, scanning electron microscopy analysis and energy dispersive X-ray (EDX) spectroscopy techniques.

It is found that, in the working range of 298-328 K, the inhibition efficiency of TTB increases with increasing concentration to attain the highest value (92 per cent) at 2.5 × 10⁻³ M. Both chemisorption and physisorption of TTB take place on the mild steel, resulting in the formation of an inhibiting film. Computational methods point to the imidazole and phenyl ring as the main structural parts responsible of adsorption by electron-donating to the steel surface, while the triazol ring is responsible for the electron accepting. Such strong donating–accepting interactions lead to higher inhibition efficiency of TTB in the aqueous working system.

This work is original with the aim of finding new acid corrosion inhibitors.

The purpose of this paper is to investigate the effects of several azole derivatives on the corrosion inhibition of irradiated and non‐irradiated plain carbon steel in 0.5 M nitric acid (HNO₃) solutions at 30‐60°C and to study the mechanism of their inhibitive action.

The inhibition efficiency was evaluated by means of weight‐loss determinations and polarization techniques at different temperatures. The type of adsorption isotherm, inhibition efficiency, surface coverage and kinetic data were determined.

The results showed that azole derivatives inhibit the corrosion of irradiated and non‐irradiated carbon steel in acidic solution. The inhibition efficiency increased with the inhibitor concentration and was greater in the case of irradiated carbon steel than for the non‐irradiated one. Kinetic parameters were calculated. The adsorption of inhibitors obeyed the Temkin Isotherm model. Thermodynamic parameters of activation were calculated in the presence of inhibitors.

Electrochemical studies such as electrochemical impedance spectra will throw more light on the mechanism of inhibition.

Azole derivatives can be used as inhibitors in acid medium and addition of halides can improve their inhibition efficiency.

The investigation revealed the possible application of azole derivatives as environmentally friendly inhibitors for corrosion prevention under specific conditions.

This paper aims to study the corrosion inhibition of Methyl 2-(benzamido)-2-(4-phenyl-1H-1,2,3-triazol-1-yl) acetate (MBPTA) and Methyl 2-(benzamido)-2-(4-p-tolyl-1H-1,2,3-triazol-1-yl) acetate (MBTTA) in 1 M H2SO4 solution at 25 °C.

The authors have used weight loss measurements, electrochemical impedance spectroscopy (EIS), potentiodynamic polarization, FT-IR, quantum chemical calculations and scanning electron microscopy (SEM) techniques.

The polarization measurements indicate that both compounds are mixed type inhibitors, and that MBTTA is more effective than MBPTA. The effect of temperature on the corrosion behavior using optimal concentration of MBTTA and MBPTA was studied in the temperature range 298-328 K. SEM was used to examine the morphology of the metal surface. Thermodynamic parameters were calculated and discussed. Monte Carlo simulations were applied to lookup for the most stalls configuration and adsorption energy for the interaction of inhibitors on Fe (1 1 1) interface. The difference in inhibition efficiencies between the two organic inhibitors can be clearly explained in terms of frontier molecular orbital theory.

The authors report on the comparative inhibiting effect of two new 1,4-disubstituted 1,2,3-triazoles, namely Methyl 2-(benzamido)-2-(4-phenyl-1H-1,2,3-triazol-1-yl) acetate (MBPTA) and Methyl 2-(benzamido)-2-(4-p-tolyl-1H-1, 2, 3-triazol-1-yl) acetate (MBTTA) on mild steel corrosion in 1 M H₂SO₄ solution.

The purpose of this paper is to perform the evaluation of copper susceptibility to corrosion in industrial cooling systems. Microstructure and defects of copper are observed, while divergences from optimum structure are discussed.

Various types of corrosion are examined. Electrochemical techniques such as electrochemical impedance spectroscopy and potentiodynamic polarisation are applied in these materials, using corrosion inhibitors. Microscopic observations and electrochemical measurements are interpreted according to possible mechanistic scenarios.

It is evident that, under specific conditions (e.g. high pH), water cooling ingredients can enhance corrosion, leading to significant copper mass loss from the inner surface of the pipe and thus leading to failure.

Evaluation of copper corrosion in cooling industrial systems was done, as well as studies of copper corrosion in sodium chloride.