Determinants of Infant Mortality in Older ASEAN Economies

Infant mortality in the Association of Southeast Asian Nations (ASEAN) has been declining, yet disparities remain between the nations. This paper therefore explores the determinants of infant mortality in the older ASEAN-4 economies, Malaysia, Thailand, Indonesia and the Philippines using an Autoregressive Distributed Lag (ARDL) Error Correction Model framework. The key findings of the study are: First, there is evidence of long-run relationships among infant mortality, education, female fertility, income and access to healthcare. Second, the determinants of infant mortality vary between countries. Female fertility emerged as the main determinant of infant mortality in Malaysia, while access to healthcare matter for infant mortality in Indonesia, and to a lesser extent for the Philippines. The income effect is significant for reducing infant mortality in Malaysia, while female education is important for Indonesia and Thailand. Third, the speed of adjustment of infant mortality rate is comparatively low in ASEAN-4

Dielectric and magnetic properties of conducting ferromagnetic composite of polyaniline with γ-Fe2O3 nanoparticles

The present paper reports the synthesis of conducting polyaniline polymer composite with nanoclusters of ferrite (γ-Fe2O3) particles in the presence of dodecylbenzene sulfonic acid in aqueous medium through electrochemical and chemical oxidative polymerization. Different formulations have been prepared to study the effect of ferrite constituent on the electrical and dielectric properties of polyaniline nano-composite. Vibrating sample magnetometer (VSM) studies and electrical conductivity measurements have revealed that conducting polymer composite has a saturation magnetization (Ms) value of 48.9 emu g−1 and conductivity of the order of 0.13 S cm−1. The particle size of γ-Fe2O3 was found in the range of 8–15 nm as analyzed by transmission electron microscopy (TEM). Fourier transform infrared spectroscopy (FTIR) results have shown the presence of characteristic band stretching of Fesingle bondO band at 630 and 558 cm−1, indicating the presence of γ-Fe2O3 in the polyaniline matrix which is in agreement with the electrochemical results. Dielectric measurements have shown decreasing trend of dielectric constant with the increase of γ-Fe2O3 particles in the polymer matrix while shielding effective (SE) of −11.2 dB was achieved for the polymer composite in 8.2–12.4 GHz (X-band) frequency range. The characterization of the composite was further carried out by X-ray diffraction, UV–vis and thermal gravimetric analysis (TGA)

Nickel Doped Zinc Oxide Thin Films for Visible Blind Ultraviolet Photodetection Applications

The current research aims to investigate the effect of nickel doping on the structural and opto-electrical characteristics of zinc oxide thin films. Sol-gel spin coating technique has been utilized to deposit Zn _1-x Ni _x O (x = 0, 0.005, 0.010, and 0.015) films on glass substrates. X-ray diffraction (XRD) analysis confirms the formation of crystalline zinc oxide thin films with hexagonal wurtzite structure. Williamson-Hall analysis has been performed to study the individual contribution of lattice strain and crystallite size to the peak broadening in the XRD pattern. Scanning electron microscopy (SEM), Photoluminescence spectroscopy, and UV–visible spectroscopic techniques have been used to examine the surface morphology and optical properties of the deposited films. Transient photocurrent measurements have been performed on all the films under the exposure of ultraviolet (UV) light of wavelengths 365 and 254 nm with on/off cycle of 100 s, and various device key parameters such as sensitivity, responsivity, and quantum efficiency, etc have been determined. Sensitivities of the fabricated photodetectors (PDs) are found to be 5463%, 3809%, 3100%, and 831% for pristine ZnO, Zn _0.995 Ni _0.005 O, Zn _0.99 Ni _0.01 O, and Zn _0.985 Ni _0.015 O, respectively. The UV photodetection mechanism, which is based on the interaction between chemisorbed oxygen on the surface of ZnO and photo-generated holes, has been thoroughly discussed

Nanostructured graphene/Fe3O4 incorporated polyaniline as a high performance shield against electromagnetic pollution

The development of high-performance shielding materials against electromagnetic pollution requires mobile charge carriers and magnetic dipoles. Herein, we meet the challenge by building a three-dimensional (3D) nanostructure consisting of chemically modified graphene/Fe3O4(GF) incorporated polyaniline. Intercalated GF was synthesized by the in situ generation of Fe3O4 nanoparticles in a graphene oxide suspension followed by hydrazine reduction, and further in situ polymerization with aniline to form a polyaniline composite. Spectroscopic analysis demonstrates that the presence of GF hybrid structures facilitates strong polarization due to the formation of a solid-state charge-transfer complex between graphene and polyaniline. This provides proper impedance matching and higher dipole interaction, which leads to the high microwave absorption properties. The higher dielectric loss (epsilon '' = 30) and magnetic loss (mu '' = 0.2) contribute to the microwave absorption value of 26 dB (>99.7% attenuation), which was found to depend on the concentration of GF in the polyaniline matrix. Moreover, the interactions between Fe3O4, graphene and polyaniline are responsible for superior material characteristics, such as excellent environmental (chemical and thermal) degradation stability and good electric conductivity