Influence of iron deficiency on electric and magnetic behavior of Ho doped BiFeO3 electroceramic

The effect of iron deficiency for the improvement of multiferroic properties of Ho doped BiFeO₃ ceramics (BiHo_XFe_1?XO₃ for x = 0, 0.05, 0.1 and 0.15) prepared by conventional solid state reaction route were investigated carefully. As pure BiFeO₃ exhibited antiferromagnetism, lossy ferroelectric (P–E) hysteresis loop and low dielectric constant value so, device integration is significantly hindered due to the presence of impurity phases associated with it. However, suitable variation of metal ion concentration in Ho doped BiFeO₃ significantly enhanced both ferroelectric and ferromagnetic properties of the samples. Therefore, increase of Ho concentration certainly favors for suppression of impurity phases in rhombohedral (R3c) structure of BiFeO₃ along with no structural transformation. On the other hand, increase of iron deficiency may suppress transformation of Fe from Fe³⁺ to Fe²⁺ as a result, the dielectric constant value of the sample increases along with large reduction of leakage current behavior.     

Pulse Reverse Electrodeposition of Cu-SiC Nanocomposite Coating: Effects of Surfactants and Deposition Parameters

Cu-SiC nanocomposite coatings have been deposited from an aqueous sulfate electrolyte using the technique of pulse reverse electrodeposition both in the absence and presence of three different types of surfactants, anionic, cationic, or nonionic. The effects of different electrodeposition parameters on some properties of the coatings have been studied. In all cases, it has been observed that the surface roughness, hardness, and resistivity increase with the increase in cathodic current density. However, they have been observed to decrease with the increase in anodic current density and the anodic current time. The variation in the amount of incorporated reinforcement with different deposition parameters has been observed to be dependent on the nature of the surfactant used. In the presence of cationic and nonionic surfactant, a noticeable increase in the amount of incorporated reinforcement and hardness has been observed. Samples prepared under higher anodic current density have been observed to possess lower stress, but intense texture. An increase in cathodic current density has been observed to decrease the extent of texturing.     

Recent advances in indium metallurgy: A review

The by-products of zinc refineries are used as the primary mineral resources for the commercial production of indium. The discarded LCDs containing adequate amount of indium is rather worth as its secondary resources compared to the by-products of zinc refineries. Mining and recycling rates of indium, respectively from minerals and waste LCDs are in progress to meet its huge demand. Recycling of the LCDs has been dominating over mining, as presently 480t of indium are produced annually from mining, however, that of 650t annually from recycling. Different aspects of the extractive metallurgy of indium are summarized in this review paper.     

Mechanistic study of Al electrodeposition from EMIC–AlCl3 and BMIC–AlCl3 electrolytes at low temperature

Aluminum was electrodeposited from two different ionic liquid electrolytes namely; 1-ethyl-3-methylimidazolicum chloride and AlCl₃ (EMIC–AlCl₃) and 1-butyl-3-methylimidazolium chloride (BMIC–AlCl₃) at 90 ± 2 °C. Nodular morphology of aluminum was obtained at the copper substrate. To evaluate the reaction mechanism, chronoamperometric study was adopted. From the chronoamperometric analysis, it was observed that the reaction was controlled by instantaneous three-dimensional diffusion process. The diffusion coefficient (D) of Al₂C₇⁻ was found to be 5.2–6.6 × 10⁻¹¹ m² s⁻¹ and 2.2 × 10⁻¹¹ m² s⁻¹ for EMIC–AlCl₃ and BMIC–AlCl₃ ionic liquid electrolytes, respectively. The nuclei density of electrodeposited aluminum on the copper was also confirmed by scanning electron microscope wherein uniformly distributed aluminum nodules were observed.     

Delay-discretization-based sliding mode $$H_{\infty }$$ load frequency control scheme considering actuator saturation of wind-integrated power system

This paper investigates the combined effect of actuator saturation and time-delay on load frequency control (LFC) of a wind-integrated power system (WIPS). Actuator saturation is represented in two different approaches such as polytopic and sector bounding. Delay-discretization-based sliding mode \(H_{\infty }\) control approach is proposed to design a novel LFC scheme. The proposed control scheme requires present as well as delayed states information as input to the controller. This requirement of control scheme is fulfilled by adopting a finite known delay. This finite known delay used in controller design is discretized into delay intervals. Lyapunov–Krasovskii functional is defined for each delay interval, and \(H_{\infty }\) stabilization criteria for the closed loop WIPS are derived in linear matrix inequality framework using Wirtinger-based inequality. The proposed control scheme is tested by considering a numerical example of two-area WIPS.

     

Assessment of Shear Stress Distribution in Meandering Compound Channels with Differential Roughness Through Various Artificial Intelligence Approach

Water Resources Management - Accurate prediction of shear stress distribution along the boundary in an open channel is the key to solving numerous critical engineering problems such as flood...     

Image retrieval based on non-uniform bins of color histogram and dual tree complex wavelet transform

Multimedia Tools and Applications - Traditional Content-Based Image Retrieval (CBIR) systems were developed for retrieving similar kinds of images from a whole image database based on the given...