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Abstract-It is a suitable means for multi-messages to usehybrid encryption to make a safe communication. Hybrid encryption confines encryption into two parts: one part uses public key systems to scramble a one-time symmetric key, and the other part uses the symmetric key to scramble the actual message. The quick advancement of the internet technology requires distinctive message communications over the more extensive territory to upgrade the heterogeneous system security. In this paper, we present a lightweight multi-message and multireceiver Heterogeneous hybrid signcryption scheme based on the hyper elliptic curve. We choose hyper elliptic curve for our scheme, because with 80 bits key give an equivalent level of security as contrasted and different cryptosystems like RSA and Bilinear pairing with 1024 bits key and elliptic curve with 160 bits key, respectively. Further, we validate these security requirements with our scheme, for example, confidentiality, resistance against reply attack, integrity, authenticity, nonrepudiation, public verifiability, forward secrecy and unforgeability through a well-known security validation tool called Automated Validation of Internet Security Protocols and Applications (AVISPA). In addition, our approach has low computational costs, which is attractive for low resources devices and heterogeneous environment.Keywords-Multi-receiver heterogeneous hybrid signcryption; multi-message and multi-receiver heterogeneous hybrid signcryption; hyper elliptic curve; Automated Validation of Internet Security Protocols and Applications (AVISPA)

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Metal-organic frameworks (MOFs) have been at the center stage of material science in the recent past because of their structural properties and wide applications in catalysis. MOFs have also been used as hard templates for the preparation of catalysts. In this study, highly active CuPt/NC electrocatalyst was synthesized by pyrolyzing Cu-tpa MOF along with Pt precursor under flowing Ar-H2 atmosphere. The catalyst was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and X-ray powder diffraction (XRD). Rotating disk electrode study was performed to determine the oxygen reduction reaction (ORR) activity for CuPt/NC in 0.1 M HClO4 at different revolutions per minute (400, 800, 1200, and 1600) and it was also compared with commercial Pt/C catalyst. Further the ORR performance was evaluated by K-L plots and Tafel slope. CuPt/NC shows excellent ORR performance with onset potential of 0.9 V (vs. RHE), which is comparable with commercial Pt/C. The ORR activity of CuPt/NC is demonstrated as an efficient electrocatalyst for fuel cell.