International Islamic University, Chittagong

About: International Islamic University, Chittagong is a education organization based out in Chittagong, Bangladesh. It is known for research contribution in the topics: Debye model & Density functional theory. The organization has 1111 authors who have published 1089 publications receiving 7918 citations. The organization is also known as: IIUC.

Comparative assessment on in vitro antioxidant activities of ethanol extracts of Averrhoa bilimbi, Gymnema sylvestre and Capsicum frutescens.

Abstract: Background: Averrhoa bilimbi, Gymnema sylvestre and Capsicum frutescens are medicinal plants commonly used as traditional medicine for the treatment of various diseases The present study was designed to investigate the antioxidant activities of Ethanolic extract of A bilimbi, G sylvestre and C frutescens Materials and Methods: The antioxidant activity of the extracts were evaluated using total phenolic and flavonoid contents, ferric reducing power and the free radical scavenging activity against 1,1-diphenyl-2-picrylhydrazyl (DPPH) Results: Total phenolic and flavonoid contents were higher in G sylvestre (5363636 ΁ 0454545 mg/g gallic acid equivalent) and C frutescens (2666667 ΁ 2081666 mg/g quercetin equivalent) respectively Reducing power of the crude ethanol extracts increased with the concentrations of the extracts and all the extracts showed moderate free radical scavenging activity against DPPH The plant extract displayed moderate phenolic and flavonoid contents compared to gallic acid and quercetin equivalent respectively, whereas also exhibited significant scavenging of DPPH radical and reducing power compared with ascorbic acid as standard Conclusion: Our study suggests that G sylvestre has significant antioxidant activity The antioxidant compound of this plant might be a therapeutic candidate against oxidative stress related diseases Different sub-fraction of A bilimbi and C frutescens should be studied further to assess the effect Further study is necessary for isolation and characterization of the active antioxidant agents for better treatment

Effect of boron incorporation into the carbon-site in Nb2SC MAX phase: Insights from DFT

Abstract: Inherent and modified characteristics of MAX phase materials are important for technological applications in different fields. From this point of view, the present article gives a brief overview of the physical properties of Nb2SC1-xBx (x = 0.0–1.0) MAX phase solid solutions via the calculations of elastic, electronic, thermal and optical properties using density functional theory (DFT). The substitutional effect of B at the C site on the physical properties of Nb2SC is also discussed. The increase of B-content (x) enhances the elastic constants (except C12 and C13) and moduli (except B), Debye temperature, melting point, and minimum and lattice thermal conductivity of Nb2SC1-xBx. Conversely, the machinability and dry lubricity decrease gradually with the increase of x. The ductility decreases with the increase of x, and when x > 0.2, Nb2SC1-xBx becomes completely brittle and the brittleness increase with further increase of x. All the compositions of Nb2SC1-xBx have potential to be used as thermal barrier coating (TBC) and high temperature structural materials. Moreover, the investigated optical parameters are discussed on the basis of electronic structures. Average reflectivity in the visible light region is more than 45%, which make Nb2SC1-xBx systems capable of reducing the solar heating. It is expected that this study will stimulate the MAX phase research community to further explore the characteristics of these materials via experiment and theory.

A Network Selection Mechanism for Fourth Generation Communication Networks

Abstract: It has been widely agreed that there will be a co- existence of different radio access technologies in fourth generation communication networks. So there will be a problem of choosing the best access network at a particular time. The selection of the best access network will depend on a number of factors. This work aims to take into account their influence in the selection of the network using a Game theoretical modeling to solve the network selection problem. The paper introduces the concepts of Strategy Space, Quality Points in the Game theoretical context and gives a mathematical mechanism for network selection. Finally it is shown that only the best network serves the service request of the user.