Inhibition effect of a new pyrimidine derivative on the corrosion of mild steel in hydrochloric acid solution

The inhibition effect of a newly synthesized pyrimidine derivative, namely 3-(2-(4-(hydroxymethyl)-1H-1,2,3-triazol-1-yl)ethyl)-2-methyl-6,7,8,9-tetrahydropyrido[1,2-a]pyrimidin-4-one, on the corrosion of mild steel in 1.0 M HCl medium was investigated using the weight loss, the Tafel extrapolation technique and the AC impedance spectroscopy. The effect of the inhibitor concentration, temperature and concentration of the acid mixture media on the inhibitor action was also studied. It was observed that the anti-corrosion efficiency increases with an increase in the inhibitor concentration, but decreases with an increase in temperature. Thermodynamic parameters for the dissolution process were determined. The adsorption of the pyrimidine derivative on the mild steel surface was found to obey the Langmuir adsorption isotherm.     

Influence of graphite filler on two-body abrasive wear behaviour of carbon fabric reinforced epoxy composites

The influence of graphite filler additions on two-body abrasive wear behaviour of compression moulded carbon–epoxy (C–E) composites have been evaluated using reciprocating wear unit and pin-on-disc wear unit under single pass and multi-pass conditions respectively. The carbon fabric used in the present study is a plain one; each warp fiber pass alternately under and over each weft fiber. The fabric is symmetrical, with good stability and reasonable porosity. Abrasive wear studies were carried out under different loads/abrading distance using different grades of SiC abrasive paper (150 and 320 grit size). Graphite filler in C–E reduced the specific wear rate. Further, the wear volume loss drops significantly with increase in graphite content. Comparative wear performance of all the composites showed higher specific wear rate in two-body wear (single-pass conditions) compared to multi-pass conditions. Further, the tribo-performance of C–E indicated that the graphite filler inclusion resulted in enhancement of wear behaviour significantly. Wear mechanisms were suggested and strongly supported by worn surface morphology using scanning electron microscopy.     

Experimental investigation on the abrasive wear behavior of nanoclay‐filled EVA/LDPE composites

The article presents the results of experimental investigation on three‐body abrasive wear behavior of nanoclay‐filled EVA/LDPE (NC‐EVA/LDPE) composites. NC‐EVA/LDPE composites with and without compatibilizer were prepared by Brabender Co‐Twin extruder (Make: CMEI, Model: 16CME, SPL) and poly(ethylene‐co‐glycidyl methacrylate) was used as the compatibilizer. The mechanical properties were evaluated using Universal testing machine. In three‐body wear tests, silica sand particles of size 200–250 μm were used as dry and loose abrasives. Three‐body abrasive wear studies were carried out using dry sand/rubber wheel abrasion test rig. The effect of abrading distance on the abrasive wear behavior of neat EVA, EVA/LDPE, and NC‐EVA/LDPE composites was reported. The results showed that the wear volume loss is increased with increase in abrading distance and the specific wear rate decreased with increase in abrading distance. However, the presence of nanoclay filler in EVA/LDPE composite showed a promising trend. Abrasive wear volume of the composites was correlated with mechanical properties such as hardness, tensile strength, and percentage elongation. However, higher weight percentage of LDPE in EVA increased the wear rate. The results indicate that NC‐EVA/LDPE with compatibilizer composite exhibits good abrasive wear resistance compared with NC‐EVA/LDPE without compatibilizer. Attempts to explain these differing trends are made in this work by analyzing the features observed on the worn surface samples by employing scanning electron microscopy (SEM). POLYM. COMPOS., 2010. © 2009 Society of Plastics Engineers     

A comparative study on properties of porous friction course mixes with neat bitumen and modified binders

This paper summarises details of the laboratory investigation on the effect of various binders on the performance and durability of porous friction course (PFC) mixes. Three different modified binders and neat bitumen were investigated for three different aggregate gradations at two predetermined binder contents. The performance was evaluated in terms of stone-on-stone contact condition, air voids, and hydraulic-conductivity of compacted PFC mixes. The structural durability was investigated based on aged abrasion loss and moisture susceptibility. The findings provide a better understanding of the effect of each binder type on the performance and durability of PFC mixes.     

Effect of hydrophobic ionic liquid loading on characteristics and electromechanical performance of cellulose

This paper presents the characteristics and electromechanical performance of hydrophobic ionic liquid namely; 1-butyl-3-methylimidazolium hexafluorophosphate (BMIPF₆) loaded cellulose. Different amount of BMIPF₆ is loaded in to cellulose via solution blending during its dissolution and regeneration in trifluoroacetic acid. Influence of BMIPF₆ loading on characteristics, mechanical and electromechanical properties are assessed by scanning electron microscopy, X-ray diffractograms, thermogravimetric analysis, tensile test and bending displacement tests. Experimental results show that thermal degradation temperature of the cellulose tends to decrease with increasing the BMIPF₆ loading, which may be due to weakening of the intra- and intermolecular hydrogen bonds of cellulose upon addition of BMIPF6. X-ray diffraction analysis showed that the raise of the BMIPF₆ content resulted in enormous reduction of peak intensities at 2θ = 12° and 20.85°. This might be due to irregular structures caused by the introduction of BMIPF₆ molecules in to cellulose, results in lower crystallinity as well as the mechanical properties. BMIPF₆ loaded cellulose actuator shows a maximum bending displacement output of 4 mm with comparatively better durability for prolonged time under relatively low humid condition.     

Semantic Analysis Techniques using Twitter Datasets on Big Data: Comparative Analysis Study

This paper conducts a comprehensive review of various word and sentence semantic similarity techniques proposed in the literature. Corpus-based, Knowledge-based, and Feature-based are categorized under word semantic similarity techniques. String and set-based, Word Order-based Similarity, POSbased, Syntactic dependency-based are categorized as sentence semantic similarity techniques. Using these techniques, we propose a model for computing the overall accuracy of the twitter dataset. The proposed model has been tested on the following four measures: Atish’s measure, Li’s measure, Mihalcea’s measure with path similarity, and Mihalcea’s measure with Wu and Palmer’s (WuP) similarity. Finally, we evaluate the proposed method on three real-world twitter datasets. The proposed model based on Atish’s measure seems to offer good results in all datasets when compared with the proposed model based on other sentence similarity measures.     

Influence of cenosphere filler additions on the three‐body abrasive wear behavior of glass fiber‐reinforced epoxy composites

The dry three‐body abrasive wear behavior of bi‐directional glass fabric reinforced epoxy composites with and without cenosphere filler have been studied using dry sand/rubber wheel abrasion tester. The angular silica sand particle sizes in the range 200–250 μm were used as dry and loose abrasives. The wear experiments have been conducted at two different loads viz., 22 and 32 N and different abrading distances viz. 270, 540, 810, and 1,080 m. The wear volume increases with an increase in load/abrading distance for all composites. From the experimental wear data it was observed that the abrasive wear of the composites dependent on the applied load and abrading distance. Further, the cenospheres filler inclusion in glass fiber reinforced epoxy (G‐E) composite showed poor abrasive wear performance. Scanning electron microscopy was used to study the morphology of the worn surface features of composites and to understand the mechanisms involved in the wear analysis. POLYM. COMPOS., 2008. © 2008 Society of Plastics Engineers     

Effect of addition of graphite particulates on the wear behaviour in aluminium–silicon carbide–graphite composites

Aluminium matrix composites with multiple reinforcements (hybrid AMCs) are finding increased applications because of improved mechanical and tribological properties and hence are better substitutes for single reinforced composites. Few investigations have been reported on the tribological behaviour of these composites with % reinforcement above 10%. The present study focuses on the influence of addition of graphite (Gr) particulates as a second reinforcement on the tribological behaviour of aluminium matrix composites reinforced with silicon carbide (SiC) particulates. Dry sliding wear tests have been performed to study the influence of Gr particulates, load, sliding speed and sliding distance on the wear of hybrid composite specimens with combined % reinforcement of 2.5%, 5%, 7.5% and 10% with equal weight % of SiC and Gr particulates. Experiments are also conducted on composites with % reinforcement of SiC similar to hybrid composites for the sake of comparison. Parametric studies based on design of experiments (DOE) techniques indicate that the wear of hybrid composites decreases from 0.0234 g to 0.0221 g as the % reinforcement increases from 3% to 7.5%. But the wear has a tendency to increase beyond % reinforcement of 7.5% as its value is 0.0225 g at.% reinforcement of 10%. This trend is absent in case of composites reinforced with SiC alone. The values of wear of these composites are 0.0323 g, 0.0252 g and 0.0223 g, respectively, at.% reinforcement of 3%, 7.5% and 10% clearly indicating that hybrid composites exhibit better wear characteristics compared to composites reinforced with SiC alone. Load and sliding distance show a positive influence on wear implying increase of wear with increase of either load or sliding distance or both. Whereas speed shows a negative influence on wear indicating decrease of wear with increase of speed. Interactions among load, sliding speed and sliding distance are noticed in hybrid composites and this may be attributed to the addition of Gr particulates. Such interactions are not present in composite reinforced with SiC alone. Mathematical models are formulated to predict the wear of the composites.     

Role of micro/nano fillers on mechanical and tribological properties of polyamide66/polypropylene composites

The objectives of this research article is to evaluate the mechanical and tribological properties of polyamide66/polypropylene (PA66/PP) blend, graphite (Gr) filled PA66/PP, nanoclay (NC) filled PA66/PP and NC plus short carbon fiber (NC + SCF) filled PA66/PP composites. All composites were fabricated using a twin screw extruder followed by injection molding. The mechanical properties such as tensile, flexure, and impact strengths were investigated in accordance with ASTM standards. The friction and sliding wear behaviour was studied under dry sliding conditions against hard steel on a pin-on-disc apparatus. Scanning electron micrographs were used to analyze the fracture morphologies. From the experimental investigation, it was found that the presence of NC and SCF fillers improved the hardness of PA66/PP blend. Further, the study reveals that the tensile and flexural strength of NC + SCF filled PA66/PP was higher than that of PA66/PP blend. Inclusion of micro and nanofillers reduced the wear rate of PA66/PP blend. The wear loss of the composites increased with increasing sliding velocity. The lowest wear rate was observed for the blend with nanoclay and SCF fillers. The wear rates of the blends with micro/nanofillers vary from 30–81% and lower than that of PA66/PP blend. The wear resistance of the PA66/PP composites was found to be related to the stability of the transfer film on the counterface. The results have been supplemented with scanning electron micrographs to help understand the possible wear mechanisms.