Polymeric membranes are extensively used for gas separations but their performance is limited by the upper bound trade‐off discovered by Robeson in 1991. Among the attractive modifications available to increase the performance of polymeric membranes, polymer blending is a unique technique because it offers a time‐ and cost‐effective method of tuning the properties of membranes. A variety of polymer blends has been explored in recent years. The application of polymer blends in gas separation membranes is described by critically analyzing the performance of polymer blend membranes. Polymer blend membranes of different polymer pairs are reviewed and evaluated in terms of phase behavior, permeability, and selectivity.

The isomeric cross-section ratio 0. /(0. +erg) for the formation of" Se was determined in the ' Ge(a, n) reaction over the energy range of 13-27 MeV, in the ""Ge('He, xn) process over 13-24 MeV, in the 'As(p, 3n) reaction over 25-45 MeV, and in the ' As(d, 4n) reaction over 28-56 MeV.Measurements were done radiochemically using the "stacked-foil" technique. In (a, n) and ('He, xn) processes the ratio is relatively high at low incident particle energies but decreases with increasing energy. In (p, 3n) and (d, 4n) reactions, on the other hand, it is practically constant. Statistical model calculations taking into account precompound emission were carried out on the four processes investigated in this work as well as on the ' Se(n, 2n) reaction reported in the literature. The total cross section (o +og) is described well by the calculation. The calculated isomeric cross-section ratio depends strongly on the input level scheme of the product nucleus. In general, however, the statistical model, under a suitable set of global assumptions, can reproduce the isomeric crosssection ratio in all the five nuclear processes.

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In this study, research will be carried out to identify the functional group behavior of glassy and rubbery polymeric blend membrane with amines. Polymeric blend membranes with different blending ratios were prepared and the developed membranes were characterized by FTIR to see the effect of blend ratio on different functional groups. The developed membranes are flat dense sheet membrane of 20% wt/wt. The pure and blend membrane polysulfone, polyethersulfone, polyvinyl acetate with different composition, with 10% methyl diethanol amine, mono ethanol amine, diethanol amine are developed with dimethyl acetamide solvent. Fourier Transform Infrared (FTIR) spectroscopy was utilized to study the interaction between two polymers and to analyze the type of bonding present. To observed frequencies were assigned to various mode of vibration in terms of fundamentals and combination. These spectral changes indicated the existence of molecular interaction among the enhanced polymeric blends; highlight the compatible nature among each other.

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