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Chromium Nitride (CrN) thin films are known for their comparatively good mechanical properties. CrN was deposited on Silicon (100) and glass substrates by using DC magnetron sputtering and the influence of the partial nitrogen content and different gaseous environment on their microstructural characteristics were investigated in the present work. The CrN films were characterised with X-Ray Diffraction (XRD), Field Emission Scanning Electron Microscopy (FE-SEM), Atomic Force Microscopy (AFM) and Nanoindentation was used to characterise the structural and mechanical properties of the deposited thin film. The films showed the [200] preferred orientation at lower (at 20%) nitrogen contents while the intensity of the peak [111] increases with the increase in the nitrogen content. The Cr2N (220) peak was identified at a nitrogen content above 30%, but for nitrogen content above 40%, the CrN phase was observed in both films deposited on Si(100) and glass substrates. The preferred orientations of the CrN thin films are strongly influenced by the nitrogen content inside the chamber as observed in the present work. The surface roughness and deposition rate were observed in a reducing trend with the increasing N2 content and temperature from 20.31 to 2.71nm and from 30.16 nm/min to 25.66nm/min, respectively. The hardness and modulus of pure N2 films deposited on the Si substrates were evaluated by nanoindentaion testing and indicated 31 GPa and 250 GPa, respectively.

We present here a case of 58-year-old male operated for coronary artery bypass graft surgery with four grafts. He developed neurologic symptoms with injection cefepime which recovered after withdrawal of the drug.

High specific stiffness materials are used to design the space payload components. These components should sustain the extreme environmental conditions throughout their life cycle, without failure. Space missions need lightweight materials which are mechanically strong with high thermal and electric conductivities. Carbon fiber reinforced polymer (CFRP) offers considerable mass saving and high strength, which is widely used for space payload components. However, it has limitations to replace the traditional space-qualified materials due to its low conductivity. Carbon Nanotubes (CNTs) are efficient with greater electrical and thermal conductivities. For CNTs to be seen as effective reinforcements for attaining high strength and conductivity of polymer composites, they need to meet the criteria of being well-dispersed by the solution mixing method. The quality of the CNT nanocomposite relies upon several parameters like the type of CNTs, purity, aspect ratio, amount of loading, alignment and interfacial adhesion between the nanotube and polymer. The performance of the CNT-CFRP composite depends on the successful execution of the processing technique. It has been intended in this review paper to highlight the enhancement of the mechanical, thermal and electrical properties of the composite, and the challenges in achieving it.  An attempt has been made to optimize the process parameters to fabricate space payload components which can be excellent alternatives to the existing high-density materials. Moreover, this review research is the need of the hour for prominent space agencies such as ISRO and NASA for their future inter-planetary missions, where payload weight needs to be kept light without making any compromise on the performance index.

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