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Austenitic stainless steels are very famous for their extraordinary resistance to corrosion, but they lack hardness. To overcome the above problem, several curing processes such as nitriding, carburizing, Carbonitriding, nitrocarburizing and Cyaniding are preferred. The AISI 316 austenitic stainless steel selected for this project work were divided into four specimens of dimensions 8 mm in diameter and 42 mm in length. Among the four samples, three were subjected to salt bath nitriding process for about 60 minutes, 120 minutes and 180 minutes at 570°C, respectively and one sample were kept untreated for comparing the results with the processed ones. Followed by case hardening, the samples were subjected to wear test using a pin-on disc machine at constant load and constant speed, 30N and 1000rpm, respectively. Then the hardness of the three specimens along with the untreated specimen were tested with a Rockwell hardness machine. All samples were undergonewith scanning electron microscopy (SEM) for microstructure analysis. And finallythe treated and untreated specimenresults were examined and compared. [ABSTRACT FROM AUTHOR]

Austenitic stainless steels are well known for its good corrosion resistance, but lacks in its ductility and hardness. To get over this, nitriding, carburizing, carbonitriding techniques are preferred. For this project work, AISI 304 Austenitic Stainless Steel of dimensions with 8 mm diameter and 43 mm length were undergone with liquid nitriding process at 60 mins, 120 mins and 180 mins and named as N1, N2 and N3 respectively. The specimens were undergone with wear test after the nitriding process. The wear test were carried out under constant load of 15N and speed of 1500rpm on a pin on disc apparatus. After the wear test, the untreated specimen of austenitic stainless steel was kept aside to compare the final results with the treated specimens. The microstructure were analysed through Scanning Electron Microscope(SEM) and the results were compared. The hardness were measured using the Rockwell hardness machine on all specimens by applying a load of 100 grams for 15 seconds. [ABSTRACT FROM AUTHOR]

A theoretical model of an amperometric biosensor with a modified electrode that inhibits the substance is addressed. The solution of a system of reaction-diffusion equations in a bounded region with a non-linear term similar to non-Michaelis- Menten kinetics of the enzymatic reaction is the basis for this model. The estimated analytical expression for the steady-state concentration profiles of reactant and product inside the thin film is provided in this paper, and it applies to all parameter values. In this paper, the power series method is used to find the given mathematical model, concentrations of substrate, product and current. The approximate analytical results are compared to numerical simulation results. It is noted that a satisfactory agreement has been reached. For the calculation of kinetic parameters and sensitivity analysis of established parameters, an analytic approach is proposed. [ABSTRACT FROM AUTHOR]

The nonlinear enzymatic reaction mechanism is explored using a mathematical model. The system of nonlinear rate equations form the basis of this model. The nonlinear differential equations have been solved analytically by the efficient variational iteration method. The most important aim is to find an analytical solution to these equations. The approximate analytical expressions of substrate, enzyme-substrate, and free enzyme concentrations are estimated. On comparing approximate solution and numerical simulation, satisfactory agreement is noted. [ABSTRACT FROM AUTHOR]