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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Nanomedicine has gained much attention for the management and treatment of cancers due to the distinctive physicochemical properties of the drug‐loaded particles. Chitosan's cationic nature is attractive for the development of such particles for drug delivery, transfection, and controlled release. The particle properties can be improved by modification of the polymer or the particle themselves. The physicochemical properties of chitosan particles are analyzed in 126 recent studies, which allows to highlight their impact on passive and active targeted drug delivery, cellular uptake, and tumor growth inhibition (TGI). From 2012 to 2019, out of 40 in vivo studies, only 4 studies are found reporting a reduction in tumor size by using chitosan particles while all other studies reported tumor growth inhibition relative to controls. A total of 23 studies are analyzed for cellular uptake including 12 studies reporting cellular uptake mechanisms. Understanding and exploiting the processes involved in targeted delivery, endocytosis, and exocytosis by controlling the physicochemical properties of chitosan particles are important for the development of safe and efficient nanomedicine. It is concluded based on the recent literature available on chitosan particles that combination therapies can play a pivotal role in transformation of chitosan nanomedicine from bench to bedside.

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Hemangiomas constitute a heterogeneous group of benign vascular proliferations of skin and mucous membranes and very rarely known to develop in the brain or spinal cord. We report here a case of multiple intracranial capillary hemangiomas presenting with transient neurological deficit. The patient underwent stealth MRI brain utilizing 15 ml of Magnevist for stereotactic localization and biopsy was done to establish the diagnosis. It is pivotal to differentiate benign hemangiomas from primary cerebral vascular tumors including hemangioblastoma, hemangioendothelioma and hemangiopericytoma, as later are known for more aggressive biologic behavior.