Composite absorbers based on conducting fabrics possessing moderate conductivity and dielectric/magnetic properties were prepared by in situ incorporation of nanoparticles of BaTiO 3 (15−25 nm) or Fe 3 O 4 (25−40 nm) within coated poly(aniline) (PANI) matrix. The X-ray diffraction patterns and transmission electron microscopy images confirmed the formation of PANI coating and incorporation of BaTiO 3 or Fe 3 O 4 nanoparticles. Scanning electron microscopy images show formation of thick and uniform coating of PANI over individual fibers and in interweave regions. The dielectric studies show that incorporation of BaTiO 3 lead to enhancement of dielectric properties of PANI whereas magnetization measurements revealed that incorporation of Fe 3 O 4 resulted in noticeable improvement in magnetic properties with saturation magnetization of 17.9 emu/g. The Ku-band (12.4−18.0 GHz) shielding studies revealed that pure PANI-coated fabric show total shielding effectiveness (SE T ) of −15.3 dB which enhanced to −16.8 and −19.4 dB after incorporation of BaTiO 3 and Fe 3 O 4 nanoparticles respectively. Such an improvement can be attributed to the better matching of input impedance, reduction of skin depth, and additional dielectric/magnetic losses. The high value of absorption-dominated SE T (i.e., 97−99% attenuation) and specific shielding effectiveness value of 17−20 dB cm 3 /g demonstrate the potential of these fabrics as promising microwave-shielding material. In addition, these fabrics also display good antistatic response with static charge decay time of only 0.11 s.

Amino acid family crystals exhibit excellent nonlinear optical and electrooptical properties. L-Alanine single crystal belongs to the amino acid group and has been grown by the slow evaporation solution growth technique at room temperature. The grown crystals were characterized by high-resolution X-ray diffractometry (HRXRD), nuclear magnetic resonance (NMR), Fourier transform infrared (FTIR) spectroscopy, UV-Vis, Raman spectroscopy, mass spectra analyses and density measurements. Its laser damage threshold was measured and its nonlinear optical response was tested by using a Q-switched Nd:YAG laser, and the value of laser damage threshold is greater than that of potassium dihydrogen phosphate (KDP).

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The potential organic NLO crystal of benzimidazole (BMZ) has been successfully grown by slow evaporation solution growth technique at room temperature. The crystalline perfection has been verified by High resolution X-ray diffraction (HRXRD) analysis. The very low angle boundary obtained for this solutiongrown specimen may be attributed to the segregation of solvent molecules (methanol), which were entrapped within the crystal during growth. The laser damage threshold has been measured by using high intensity Qswitched Nd:YAG laser. The observed value is greater than that of KDP and lesser than that of melt grown benzimidazole. The NLO efficiency has been determined and it is compared with the KDP crystal. The thermal behaviour has been assessed by TG/DTA analysis.