β–Naphthalene sulphonic acid (β–NSA) doped polyaniline (PANI)–flyash (FA) composites have been prepared by chemical oxidative polymerization route whose conductivity lies in the range 2.37–21.49 S/cm. The temperature dependence of electrical conductivity has also been recorded which shows that composites follow Mott's 3D–VRH model. SEM images demonstrate that β–NSA leads to the formation of the tubular structure with incorporated flyash phase. TGA studies show the improvement in thermal stability of composites with increase in loading level of flyash. Complex parameters i.e. permittivity (ɛ* = ɛ′- iɛ″) and permeability (μ*=μ′- iμ″) of PANI-FA composites have been calculated from experimental scattering parameters (S11 & S21) using theoretical calculations given in Nicholson–Ross and Weir algorithms. The microwave absorption properties of the composites have been studied in X-band (8.2 – 12.4 GHz) & Ku–Band (12.4 – 18 GHz) frequency range. The maximum shielding effectiveness observed was 32dB, which strongly depends on dielectric loss and volume fraction of flyash in PANI matrix.

Flexible microwave absorber composite films of carbon black (CB)/barium hexaferrite nano-discs (BaF) in polyvinyl alcohol (PVA) matrix, fabricated by gel casting, exhibit ∼99.5% attenuation of electromagnetic waves in the entire 8–18 GHz (X and Ku-band) range. The X-ray diffraction and Raman spectroscopy studies confirm the formation of CB-BaF-PVA composite films. The electromagnetic absorption properties of composite films are found to be enhanced with CB content due to the synergetic effect of multiple dielectric and magnetic losses. The 25 wt. % CB grafted PVA-BaF flexible composite films with a thickness of ∼ 2 mm exhibit effective electromagnetic shielding of 23.6 dB with a dominant contribution from absorption mechanism (SEA ∼  21 dB). The dielectric properties of composite films are further discussed by using the Debye model. The detailed analysis reveals that major contribution to dielectric losses is from dipolar and interfacial polarizations, whereas magnetic losses are predominantly from domain wall displacement.

This article has examined the determinants of export and import flows of countries in the South Asia through estimations for a country panel data of eight countries during the period 1985–2011 using a gravity model. The estimated result suggests that gross domestic product (GDP) and population among other factors can explain export and import flows. Perhaps the most important finding of the study is that South Asia Free Trade Agreement (SAFTA) has produced trade creation among its members. Finally, the study found that geographic distance might be impeding trade, and tariff has negative effect on the trade. The study also found that the nature of trade is intra-industry among the member countries of South Asian Association for Regional Cooperation (SAARC).

This article aims to understand the drivers of foreign direct investment (FDI) inflows and its nexus with its determinants such as economic growth, inflation rate, labour productivity, infrastructure development, market size, openness of the economy, political stability and corporate tax for South Asian Association for Regional Corporation (SAARC) countries. The article is based on secondary data from the World Bank and International Labour Organization (ILO) for 19 years from 2001 to 2018 for 6 SAARC countries, viz. Bangladesh, Bhutan, India, Nepal, Pakistan and Sri Lanka. The findings indicate that there exists long-run, short-run and joint causal relationship among infrastructure development, market size, openness of the economy, political stability and corporate tax and FDI inflows. Among these variables, the corporate tax is the most important one because it shows bidirectional causality with FDI inflows in the long run as well as short run along with joint strong causality. However, only the coefficients of infrastructure development and corporate tax were found to be positively and negatively significant, respectively. Therefore, better infrastructure development and decrease in corporate tax may enhance FDI inflows in SAARC countries. This infers that with the decrease in corporate tax, more FDI inflows may take place, and higher FDI inflows may decrease in corporate tax further. Therefore, this article suggests that SAARC countries should accelerate the process of integration of their economy with the rest of the world along with political stability, enhance the infrastructure facility and reduce the corporate tax to get the higher FDI inflows. JEL: F21, F02, C22

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