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In the present work, monolithic LPS-SiC was fabricated by hot press method with the addition of Al₂O₃, Y₂O₃ and SiO₂ and annealed at different temperatures to observe microstructure evolution. Process temperature was varied from 1760°C to 1800°C. Process pressure and maturing time are 20MPa and 1h respectively. Hot pressed samples were cut into rectangular bars. Three-point flexural strength was measured at room temperature in air with a cross-head speed of 0.1 mm/min and a lower span of 18 mm. Flexural strength and elastic modulus measurement was performed using a universal test machine (INSTRON 5581, USA). The apparent density of the sintered body was measured by the Archimedes method. The specimen dimension of the heat treatments is 4W×25L×1.5T mm. The specimens used for weight-loss measurement were set into an open carbon crucible to avoid nonuniform temperature distribution within the furnace. Post-fabrication heat treatment was performed in vacuum atmosphere (PO2 ≈ 0.01 Pa). The temperature was increased at a rate of 20 K/min to the heat-treatment temperature and maintained for 10 hours, after which the specimens were furnace cooled. After heat-treatment, weight of heat-treated specimens was carefully measured by an electronic balance. In order to reveal the microstructural change in heat-treated specimen, X-ray diffractometry and microstructure observation were performed and compared with those of the as-fabricated one.

The smart wearable devices that can track the fitness activities are getting famous these days due to their easy-to-use features. The fitness trackers can work for an individual in a promising manner, provided that the user is well familiar with the device and is committed with the timelines. Several reports have provided evidence that these smart wearable devices have not showed promising results and in most of the cases, people have stopped using them, few weeks after the purchase. There are several reasons linked with this response. During this research, we have worked on the correlations of weight loss via smart device with the age, gender, body mass index (BMI) and ideal body weight (IBW), with the aid of gradient boosted decision trees (XGBoost) and support vector machine (SVM) learning tools. XGBoost and SVM are capable of dealing with complex datasets, with higher frequencies, and for data emerging from multiple sources. These machine learning tools use kernel functions for the clustering and other classification measures, and are thus better as compared to the logistic methods. Next, the time series forecasting tools are discussed with the Bayesian hyperparametric optimization. The time series of the weight loss monitoring of each individual, depicted in this manner, provided complex fractal patterns, with reduction in amplitude, with the passage of time.

The inhibitive characteristics of aqueous extracts from mangrove (Rhizophora apiculata) bark and leaf on the corrosion of mild steel (MS) coupon in 1 M HCl were examined by means of the gravimetric measurement (weight loss), electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization techniques. The MS surface morphologie were investigated using field emission scanning electron microscopy (FESEM) with Energy Dispersive X-Ray Analysis (EDX) at 120h in the presence and absence of green inhibitors in corrosive medium. Respective inhibition efficiencies of 68.1% and 59.0% were obtained when exposed to 10% v/v Rhizophora apiculata solution for 72h. Examination of the adsorption behavior of the solutions indicated the Langmuir isotherm model as being the most likely relevant adsorption mechanism. In addition, polarization measurements showed that both bark and leaves extract inhibitors act via mixed type inhibition.

The extraction of linseed oil (LO) was realized by refluxing method. The extracted oil was identified by gas chromatography method coupled with mass spectrometry (GC-MS). In order to contribute to the protection of the environment, one contemplates to try on LO as a green corrosion inhibitor. The corrosion inhibition of LO was studied by weight loss and electrochemical methods. The obtained results showed that the LO is an effective inhibitor of the carbon steel corrosion in 1M HCl solution, the inhibition efficiency increased with concentration to reach 88% at 200ppm. Furthermore, the adsorption of the inhibitor on the surface of metal in 1M HCl solution was found to obey Langmuir’s adsorption isotherm. The influences of temperature were also studied in the range from 298K to 328K. The kinetic and thermodynamic data of activation dissolution process were determined and discussed.

Canthium parviflorum leaf extract (CPLE) was utilized for corrosion prevention against mild steel (MS) in 0.5molL${}^{-1}$ H₂SO₄ test medium. Standard corrosion measurement techniques (gravimetric and electrochemical) were employed for this purpose. Gravimetric tests clearly confirmed that the prepared CPLE efficiently performs as corrosion inhibitor. Potentiodynamic polarization measurements (PPM) and electrochemical impedance spectroscopy (EIS) measurements were performed in order to analyze the charge transfer process of CPLE. Polarization curves indicate that CPLE acts through mixed mode inhibition. Impedance study reveals that the CPLE additives enhances the charge transfer resistance values and conversely decreases values of double layer capacitance. Scanning electron microscopy (SEM), Ultraviolet-Visible (UV-Vis) spectroscopy analysis and Fourier-Transform Infrared spectroscopy (FTIR) were done to confirm the Fe-CPLE complex formation on MS. The effect of temperature reveals that the inhibition efficiency increases with decrease in temperature and increase in concentration of CPLE (maximum of 4mgL${}^{-1}$). The adsorption of CPLE shows that it obeys Langmuir’s isotherm model with free energy of adsorption, $\mathrm{\Delta }{G}_{\mathrm{\text{ads}}}=-1.76$kJ mol${}^{-1}$. A suitable adsorption model is also proposed.

The corrosion inhibition performance of novel synthesized thiosemicarbazide derivative namely, 2-isonicotinoyl-N-phenylhydrazinecarbothioamide (IPC) on the mild steel coupon surface in 1M hydrochloric acid solution is investigated by weight loss measurements. The adsorption parameters of the IPC on the mild steel coupon surface have been evaluated and the surface morphology of the tested mild steel is studied by scanning electron microscope (SEM) technique. The results of this study demonstrate a significant inhibitor (IPC) for mild steel and showed the highest inhibitive efficiency of 96.3% at 5mM as optimum studied inhibitor concentration. The adsorption of IPC molecules on a mild steel coupon surface is obeyed completely by the model of Langmuir adsorption isotherms. SEM has been applied to analyse the layer of IPC molecules which formed on a mild steel coupon surface as a protective layer. The inhibition efficiency (IE) of IPC from weight loss techniques and SEM analysis was harmonic with each other. The Density Functional Theory (DFT) computations have been applied to evaluate the adsorption sites of the IPC molecules and the quantum chemical calculations correlation of IPC molecules with methodological results are discussed. The energy of the highest occupied molecular orbital (EHOMO) shows a significant tendency of the IPC molecules to donate pairs of electrons to the iron atoms on the surface of mild steel. The energy of the lowest unoccupied molecular orbital (ELUMO) for IPS molecules reveals a high tendency to accept electrons from iron atoms on the surface of mild steel.