Amit Kumar Singh

Compressive behaviour of a nickel superalloy Superni 263 honeycomb sandwich panel

Metallic thermal protection systems comprising of sandwich panels consisting of hexagonal honeycomb sandwich structures are envisaged to be used in advanced transportation systems like hypersonic vehicles and reusable launch vehicles. The assessment of compressive mechanical behaviour is necessary to understand the response of sandwich structures to aerothermal loads. The fabrication methodology for realizing Ni based superalloy Superni 263 hexagonal honeycomb sandwich panels is established. This work is aimed at understanding the effect of sandwich panel geometry parameters like hexagonal cell size and core thickness on the out-of-plane flatwise compressive behaviour at room temperature. The ultimate compressive strength decreases with increasing core height irrespective of the cell sizes investigated. The dependence of specific compressive strength on the cell size is established by a power law relationship. The compressed sandwich panels subjected to understand the deformation behaviour indicated the dominance of cell wall bending and occasional fracture, however in the case of sandwich panels with higher core thickness cell wall buckling coupled with shearing at the face sheet vicinity is noticed.

Synthesis of Nanoparticle Assemblies: general discussion

Madhura Som, Sristi Majumdar, Nirmalya Bachhar, Guruswamy Kumaraswamy, G. V. Pavan Kumar, Vinothan N. Manoharan, Sanat Kumar, Madivala G. Basavaraj, Siddharth Kulkarni, Ranjini Bandyopadhyay, Sudeep Punnathanam, Himani Medhi, Ajeet Srivastav, Daan Frenkel, Mukta Tripathy, Erika Eiser, Lola Gonzalez-Garcia, Priyadarshi Roy Chowdhury, Jayant Singh, Vimala Sridurai, Alison Edwards, B. L. V. Prasad, Amit Kumar Singh, Michael Bockstaller, Neena S. John, Jyoti Seth, Mayank Misra, Charusita Chakravarty, Vandana Shinde, Rajdip Bandyopadhyaya, Jacques Jestin, Radhika Poojari, Nicholas Kotov, Oleg Gang, Alamgir Karim, Yon Ju-Nam, Steve Granick, Semen Chervinskii and Andrea Tao

Endovascular repair of giant iatrogenic femoral artery pseudoaneurysm: case report and literature review

Femoral Artery Pseudoaneurysm (FAP) is one of the most troublesome complications after various invasive cardiovascular procedures related to the femoral arterial access site. It occurs in 0.8% to 2.2% post Intra Aortic Balloon Pump (IABP) removal Messina et al. (J Vasc Surg 13:593–600, 1991). Doppler flow mapping confirms the diagnosis. Angiography provides information regarding native vessel morphology and the relation of the pseudoaneurysm to major branches. Ultrasound-Guided Compression Repair (UGCR) has been a successful modality of FAP management while minimally invasive percutaneous treatments include thrombin injection, coil embolization and insertion of covered stents. We report a case of iatrogenic FAP who was a high risk candidate for UGCR or surgical repair. She was successfully managed by percutaneous implantation of endovascular covered stent with a rapid return to ambulatory activity and minimised hospital stay. This treatment method may be a safe and effective alternative to surgery in selected patients.