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A design concept of a compact printable orientation independent chipless radio frequency identification tag is presented with near-field and far-field reading techniques. The tag consists of a circular patch loaded with multiple slot ring resonators and it has the advantage to be read from any orientation with the reader due to its symmetric structure. This tag does not have a ground plane and has higher data density and lower cost compared to the most other existing printable chipless tags. Proximity and slot reading techniques are described in details for different applications. This single-sided, compact and orientation independent tag has a great potential to be used in millions both for identification and authentication.

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Nanoparticles are key components in the advancement of future energy technologies; thus, strategies for preparing nanoparticles in large volume by techniques that are cost-effective are required. In the substitution of fossil-fuels by renewable energy resources, nanometersized particles play a key role for synthesizing energy vectors from varying and heterogeneous biomass feedstocks. They are extensively used in reformers for the production of hydrogen from solid, liquid, or gaseous energy carriers. Catalyst activities depend critically on their size-dependent properties. Nanoparticles are further indispensable as electrocatalysts in fuel cells and other electrochemical converters. The desire to increase the activity per unit area, and decrease the necessary amount of the expensive catalytic standard, It is clear that performance and commercialization of fuel cells depend on electrode materials performance. The application of pt  nanomaterials as an electrode in the field of fuel cell  has become a new, growing area of interest in recent years. We review chemical process for synthesis of pt nanoparticles. Recent developments in syntheses process of pure & mixed platinum nanoparticles has briefly reviewed specifically for applications in fuel cells. As the physicochemical properties of noble-metal nanostructures are strongly dependent upon shape and size, the development of reliable synthesis methods for the production of nanocrystals with well-defined size and morphology have been discussed briefly. The role of nanostructured supports for the nanoparticles, such as ordered mesoporous carbon, dendrimer have also discussed. And size of the nanoparticles obtained in deferent process and their temperature dependence has also discussed briefly.