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an emerging material, liquid metal when used in combination with polydimethylsiloxane (PDMS) finds applications in soft/ flexible and wearable electronics. [2] Due to its flexibility and deformability, liquid metal encapsulated in PDMS has recently shown self-healing characteristics after damage on the device. [7][8][9] Gallium-based liquid metal has been explored in various applications ranging from electrocardiogram, [10] microcooling, [11] thermometers, [12] flexible electrodes, [13,14] flexible interconnection, [15] strain sensors, [16] pressure sensors, [17] inkjet printing, [18] energy harvesting, [19,20] and magneto-hydrodynamic pumps. [21] Metasurface-based frequency selective surface (FSS) exists in 1D or 2D as periodic arrays of sub-wavelength metallic elements on dielectric surfaces. [22,23] Based on material, physical construction, [24] and geometry, [25] the FSSs are classified into high-pass, low-pass, band-pass, and bandstop filter. [25,26] The performance and behavior of the FSS is dependent on the geometry, periodicity, array size, and choice of materials (conductivity and permittivity). [24] The FSSs have been extensively studied [27] since 1960s, however its fundamental origin can go back to Marconi and Franklin's patent of reflectors in 1919. [28] The ability to tailor FSSs to curtail certain frequency band makes it a vital component in communication applications including radar, [23,29,30] microwave absorber, [29] satellite, [23,31] electromagnetic interference shielding, [32] dichroic sub reflectors, [33] reflect array lenses, [34] lens antenna, [35] polarizers, [36] stealth blankets, [37] and wireless networks. [23,38] Traditional metasurfaces have been realized on rigid substrates using materials such as glass, [23] quartz, [39] polytetrafluoroethylene (PTFE) reinforced with glass, [40] commercially available FR-4-based printed circuit boards, [41][42][43] Rogers 5880 PTFE composites supported with glass microfibers. [44] The varactor diodes like BB 837 or BB 857-02 V, [41,45] liquid crystal, [40,46] and silver paint were either soldered, [41] filled/deposited, [40,46] or painted into these mechanically rigid substrates. [23,47] Recently, liquid metal injection in all connected microfluidic channels in PDMS has been used to realize physically flexible metasurfaces with or without incorporation of soldered chip resistors. [48,49] While the metasurface is flexible, serial injection/withdrawal of liquid metal in all connected microfluidic channels may limit its application (e.g., metasurface that needs unconnected patterns). Injection filling is also known for leaving airgaps and may cause device delamination. [50] A flexible self-healing metasurface using gallium-based liquid metal encapsulated in polydimethylsiloxane (PDMS) operating in the X-band (8-12 GHz) is reported. A band-stop metasurface with center frequency at 9.82 GHz is designed using floating patches surrounding the respective end cap of a Jerusalem cross. A large-scale (up to 10 × 10 array) metasurface is patterned in PDMS and ...

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Abstract-Nanotechnology is not new and is known to exist for ages, be it in the sword of tipu sultan or in the windows of the medieval churches in Europe. A common question in the minds of all of us living in today's world is about how the mechanism of nanotechnology can be used in the healthy compatibility with the constructional structures like that of massive buildings and bridges, which have been thought to encroach upon huge masses of land, leading to the destroying of homes of wildlife and putting pressure in the limited reserves of energy. This review paper focuses on the sustainable usage of nano based materials like carbon nanotube, electrochromic windows, nanoclays, sandvik nanoflex™, nanowires, titanium dioxide, nanoceramic coating, nanocrystalline materials, nanosilica, nanocomposites, MMFX2 steel, nanometals, nanofibres, nanomyte™ mend MW, nanocement, which could be used for providing singular or multiple functions of potential reinforcement, corrosion resistance, insulation, fire protection, temperature resistance, reducing air conditioning loads, pollution control, UV ray absorption, lighting, when used as a part of building materials.Index Terms-Nanotechnology, construction, materials. I. INTRODUCTIONNanotechnology concerns with the usage of materials falling in range of few to less than 100 nanometers [1]. Constructional structures form a very important part while contributing to the GDP of any economy by rendering services ranging from transportation to living to producing useful products to earning livelihood, and at the same time also commanding a very dominant share of the energy produced for utilization, no wonder that it has been estimated by a certain source that construction industry involving nanotechnology will occupy the eighth position out of the ten, having an impact on the world's development [2]. The usage of nanotechnology materials while being incorporated in constructional structures would not only help in prolonging their lifetime, but would also keep a check on the energy spent by them and at the same time gauging their reactions and reacting to different agents like fire, corrosion, water penetration, fractures, cracks, etc. Hence the literature segment of this review paper provides a list of nano-materials that can be used for these varied tasks. II. CARBON NANOTUBESLaser ablation, chemical vapor deposition, electric arc processes are some of the methodologies employed for the Manuscript received June 4, 2013; revised August 6, 2013. B. B. Das is with National Institute of Construction Management and Research (NICMAR), Farmagudi (Ponda), Goa, India (e-mail:bibhutibhusan@gmail.com, bdas@nicmar.ac.in).Arkadeep Mitra was with KIIT Deemed University, Bhubaneswar, Odisha, India (e-mail:arkadeep123mitra@gmail.com).production of NT's (nanotubes) that exist as metals or semiconductors. Exhibiting sp 2 hybridization with walls of graphene held together in hexagonal arrays by van-der-waal force of a cylindrical honey comb like structure of an allotrope of carbon, gives a succinct d...