Electromagnetic Wave Absorption Properties of La-Doped Strontium M-Type Hexagonal Ferrite in a 18–40 GHz Frequency Range

Journal of Electronic Materials - This article examines the performance of the M-type lanthanum-doped strontium hexaferrite with general formula Sr1–yLayFe12O19 (y?=?0.00, 0.10,...     

Wheat starch production,structure, functionality and applications—a review

Starch is the main component of wheat having a number of food and industrial applications. Thousands of cultivars/varieties of different wheat types and species differing in starch functionality (thermal, retrogradation, pasting and nutritional properties) are grown throughout the world. These properties are related to starch composition, morphology and structure, which vary with genetics, agronomic and environmental conditions. Starches from soft wheat contain high amounts of surface lipids and proteins and exhibit lower paste viscosity, whereas that from hard cultivars contain high proportion of small granules and amylose content but lower gelatinization temperature and enthalpy. Waxy starches exhibit higher‐percentage crystallinity, gelatinization temperatures, swelling power, paste viscosities and digestibility, but lower‐setback viscosity, rate of retrogradation and levels of starch lipids and proteins than normal and high‐amylose starches. Starches with high levels of lipids are less susceptible towards gelatinization, swelling and retrogradation and are good source of resistant starch, while that with high proportion of long amylopectin chains are more crystalline, gelatinize at high temperatures, increase paste viscosity, retrograde to a greater extent and decrease starch digestibility (high resistant and slowly digestible starch and low rapidly digestible starch).     

Zinc: The Metal of Life

The importance of zinc was 1st reported for Aspergillus niger. It took over 75 y to realize that zinc is also an essential trace element for rats, and an additional 30 y went by before it was recognized that this was also true for humans. The adult body contains about 2 to 3 g of zinc. Zinc is found in organs, tissues, bones, fluids, and cells. It is essential for many physiological functions and plays a significant role in a number of enzyme actions in the living systems. Bioinformatics estimates report that 10% of the human proteome contains zinc‐binding sites. Based on its role in such a plethora of cellular components, zinc has diverse biological functions from enzymatic catalysis to playing a crucial role in cellular neuronal systems. Thus, based on the various published studies and reports, it is pertinent to state that zinc is one of the most important essential trace metals in human nutrition and lifestyle. Its deficiency may severely affect the homeostasis of a biological system. This review compiles the role of zinc in prophylaxis/therapeutics and provides current information about its effect on living beings.     

Ferromagnetism in Gd-doped CdS dilute magnetic semiconducting nanorods

Cd _x Gd_1?x S (x = 0–0.15) nanorods have been synthesized by solvothermal technique. X-ray diffraction study reveals that pure and Gd-doped CdS nanorods exhibits hexagonal wurtzite structure. Transmission electron microscopy reveals nanorods like morphology of synthesized CdS having 14 and 26 nm size of pure and 15 % doped CdS nanorods. UV–Visible absorption study confirms the blue shift in the energy band energy due to the quantum confinement effects. Photoluminescence spectra confirm the defect free nature of the synthesized nanorods with peaks emerging around 528 and 540 nm due to the green emission. The magnetic study shows that the pure and Gd-doped CdS nanorods exhibits ferromagnetic character and the magnetisation increased by five times from 0.074 to 0.422 emu/g upon Gd-doping.     

Influence of surface modification by 2-aminothiophenol on optoelectronics properties of ZnO nanoparticles

In this study, a precipitation method was used to synthesise ZnO nanoparticles using suitable precursors. An efficient surface modification method was proposed in order to reduce the agglomeration among synthesised small sized ZnO nanoparticles using 2-aminothiophenol as a capping agent. This article briefly investigated the effects of capping agent like 2-aminothiophenol on the optoelectronic properties of ZnO nanoparticles. The modified effectivity of 2-aminothiophenol has been examined on the nanosized ZnO nanoparticle for fluorescence and UV–visible (UV–vis) studies. The mechanism was studied for ZnO nanoparticles light emitting capability under different conditions. By facilitating the capping of ZnO with 2-aminothiophenol, fluorescence emission of the surface defects vanishes and ultraviolet (UV) emission increases. Surface capping by 2-aminothiophenol effectively covers most of the surface defects of ZnO and results in quenching of the visible region. The UV–vis absorption spectra of modified ZnO nanoparticles has been influenced by modified ZnO nanoparticles as a result of surface modification; where marked blue shift in absorption edge results. By surface modification of ZnO nanoparticles, change in optoelectronics properties has opened the new scope and possibilities to explore and fine tune the optical character of the modified ZnO for various optoelectronics applications such as UV laser.     

A novel robust logo watermarking scheme using fractional M-band wavelet transform

Digital watermarking, means of hiding/inserting a message, which can be an image, audio, video or text within the digital media. This hidden/inserting message can be later being extracted or detected for a variety of purposes. In this paper, a novel multi-resolution logo watermarking scheme using fractional M-band wavelet transform (Fr-M-band-WT) is proposed. The watermark is embedded in the multiresolution Fr-M-band-WT coefficients of low frequency bands of the host image using singular value decomposition (SVD). A multi-resolution nature of Fr-M-band-WT is exploited in the process of edge detection. Experimental results of the proposed logo watermarking scheme are compared with the previously available watermarking algorithms, fractional Fourier transform (FrFT), fractional wavelet transform (FrWT). Further, the proposed watermark extraction scheme is also tested on different attacks. The results after being investigated the proposed watermarking scheme shows a significant improvement as compared to other existing methods.