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In this research work an attempt to investigate the influence of different single component oxide flux in Activated Metal Inert gas (MIG) welding of AISI 316L. Two different fluxes SiO2, Cr2O3 were used to bead on plate welding. 6 mm thick plate of stainless steel weld with MIG welding, Carried out under some process parameter. The process parameters such as welding speed, current, Arc voltage and response are welding dimension such as depth of penetration, Bead width were studied. The Welding experiments were conducted with L9 orthogonal array using minitab 16 softwere. A Same Nine set of parameter used for the without flux, With Sio2 and with Cr2O3 flux. Total 27 experimentshad done at work. AHP-MOORA and ASRS method was applied to optimizing the MIG welding process parameters and result indicated the enhanced penetration in weld achieved with use of fluxes Sio2, Cr2O3. On the basis of present result it is considered that the centripetal Marangoni convection & Constricted arc as a mechanism in increasing the penetration of activated MIG welding. The metallurgical characteristic Hardness of weldment was evaluated using Vickers-Hardness. The purpose of this work to investigate the effect of oxide fluxes on weld morphology & welding parameter. The optimization of Parameter with using AHP-MOORA and ASRS method.

Absorption of drugs across any mucosal tissue may involve interactions with the mucus gel overlying the tissue. Drug binding to the mucus glycoproteins, in particular, can reduce the amount of free drug available for absorption. In order to evaluate the extent of drug binding to mucin, a purified model mucus system containing primarily the large glycoprotein fraction (400 kDa) of gastric mucus was developed for use in drug binding studies. The extent of binding of six selected compounds (albuterol, rifampicin, p-amino-salicylic acid, isoniazid, pyrazinamide, and pentamidine) to mucus glycoproteins was studied. The binding of each drug to a model plasma protein, bovine serum albumin (BSA), was also investigated. Binding studies were performed by diafiltration, which combines characteristics of equilibrium dialysis and ultrafiltration in a continuous system. All the compounds selected showed affinities of the same order of magnitude to mucin despite being chemically dissimilar and exhibiting differing ionization states. This suggests that binding to gastric mucus glycoproteins is non-specific in nature with similar types of binding forces involved in the binding of all the compounds tested. Results also showed that the drug-protein association constants for BSA and mucin were of the same order of magnitude only for drugs with low binding affinities. When the binding constants to BSA were moderate to high, the corresponding drug binding constants to mucin were lower by at least one order of magnitude. Based on these results, it can be concluded that the binding behavior of drugs to gastric mucin is non-specific in nature with binding constants of a low magnitude. BSA cannot be used to estimate binding to mucin, especially when the drug exhibits moderate to high affinity for BSA.

A purified model in vitro mucus system containing primarily the large, 400 kDa glycoprotein fraction of mucus has been developed for use in drug permeability and drug binding studies. The effect of protein solutions, either bovine serum albumin (BSA) or purified porcine gastric mucus, on the permeability behavior of five drugs was studied. The drugs chosen were isoniazid, pentamidine, rifampicin, p-aminosalicylic acid, and pyrazinamide, all of which can be potentially delivered as pulmonary aerosols. BSA was included in the permeability studies for comparison with previously obtained data regarding their binding behaviors to mucin relative to BSA. A custom membrane holder with a 3 mm chamber for mucin or other solutions was used in a Side-Bi-SideR diffusion apparatus to measure drug permeation through the solutions. Apparent permeability coefficients were calculated for each barrier in the series barrier system, with a protein solution being one of the barriers. The protein solutions significantly reduced the permeability of the drugs studied compared with their permeability through blank buffer solution. Both the lag time and the steady-state flux of the compounds were altered in the presence of protein indicating that there is more than protein binding affecting permeability. Such reductions in permeability coefficients need to be considered for all compounds that must traverse any mucosal surface prior to absorption or action.