Microstructure induced ultra-high energy storage density coupled with rapid discharge properties in lead-free Ba0.9Ca0.1Ti0.9Zr0.1O3–SrNb2O6 ceramics

Novel lead-free (1-x)Ba_0·9Ca_0·1Ti_0·9Zr_0·1O₃-xSrNb₂O₆ ceramics were synthesized via a two-step high energy ball milling process. The evolution of microstructural properties, phase transformation, and energy storage characteristics was comprehensively investigated to assess the applicability of material in multi-layered ceramic capacitors. The substitution of SrNb₂O₆ (SNO) in Ba_0·9Ca_0·1Ti_0·9Zr_0·1O₃ (BTCZ) has resulted in substantial improvement in materials density along with a small increase in the grain size of the synthesized ceramic. A thorough microstructural investigation indicates an excellent dispersibility and compatibility between BTCZ and SNO phases. With an increase in SNO substitution, a transition from typical ferroelectric to relaxor ferroelectric has been observed, which has led to a significantly slimmer ferroelectric loop along with frequency dispersive dielectric properties. The optimized composition (i.e., x = 0.10) exhibits an ultra-high recoverable energy density of 2.68 J/cm³ along with a moderately high energy efficiency of 83.4%. Further, SNO substituted samples have also shown an enhancement in breakdown strength. The improvement in energy storage performance and breakdown strength of SNO substituted BTCZ composites are mainly attributed to relatively homogeneous grain morphology, optimum grain size, microstructural density, and improved grain boundary interface.     

Emergence of relaxor behavior along with enhancement in energy storage performance in light rare-earth doped Ba0.90Ca0.10Ti0.90Zr0.10O3 ceramics

Nano-sized light rare-earth (La, Pr, Nd, and Sm) doped Ba_0.90Ca_0.10Ti_0.90Zr_0.10O₃ ceramics were synthesized to enhance the energy storage performance. The Rietveld study of bare and doped samples has shown tetragonal crystal symmetry and a single-phase perovskite structure. The rare-earth addition in Ba_0.90Ca_0.10Ti_0.90Zr_0.10O₃ has resulted in a remarkable change in the microstructure of the doped samples. The addition of Nd in Ba_0.90Ca_0.10Ti_0.90Zr_0.10O₃ lattice has resulted in optimum grain size and density among the five compositions. As a result of improvement in morphological characteristics in the Nd-doped sample, the dielectric, ferroelectric and piezoelectric characteristics were significantly enhanced. The Nd-doped sample has shown a relaxor behavior with a maximum dielectric constant of 10788 combined with a high saturation polarization of 41.88 μC/cm². Further, the material has shown optimum electromechanical behavior with excellent aging characteristics. The obtained properties of Nd-doped Ba_0.90Ca_0.10Ti_0.90Zr_0.10O₃ sample justifies its potential application in multi-layer energy storage capacitors.     

Effect of silica on the ZnS nanoparticles for stable and sustainable antibacterial application

Silica-capped Zinc Sulfide (ZnS) nanoparticles were synthesized for the use as stable and long-term antibacterial agents because silica is a very important component in food packaging applications for moisture absorption in tune with its property of biocompatibility and water solubility. The variation in morphological and optical properties of core-shell nanostructures was studied by changing the concentration of silica in a core-shell combination. The structural and morphological properties of silica-capped ZnS have been observed by powder X-ray diffraction (PXRD) and transmission electron microscopic (TEM) studies, respectively. Uncapped ZnS nanoparticles with particle size of 2-4 nm in a highly agglomerated state have been observed from TEM, which shows that they can be used only for short-term antibacterial action despite its excellent zone of inhibition (antibiotic sensitivity). However, ZnS/SiO₂ core-shell nanostructures are highly monodisperse in nature and the particle size increases up to 5-8 nm with increase in silica concentration. Fourier-transform infrared spectroscopy (FTIR) analysis confirms the formation of silica capping on the ZnS surface. The inhibition of defect-related emission by silica capping in energy-resolved photoluminescence studies also shows the formation of very stable ZnS nanoparticles. To study the antibacterial properties of the pure and silica-capped ZnS nanostructure the agar-well diffusion method was employed against both gram-positive and gram-negative bacteria. The obtained results indicate that pure ZnS shows excellent antibacterial action but it can last only for few days.     

Fabrication and optimization of polypyrrole/cerium oxide/glassy carbon sensing platform for the electrochemical detection of flupirtine

Journal of Applied Electrochemistry - In spite of single nanomaterials, nanocomposites have come to be the superior modifying materials for electrochemical sensing. Herein, the highly...     

Nanostructured lipid carriers based nanogel for meloxicam delivery: mechanistic,in-vivo and stability evaluation

Aim: Our investigation was aimed to investigate the potential suitability of meloxicam-loaded nanostructured lipid carriers (MLX-NLC) gel for topical application.

Main methods: MLX-NLC gel was prepared and in vivo skin penetration ability of the NLC gel was evaluated using confocal laser scanning microscopy. We studied the effect of MLX-NLC gel on the changes in lipid profile of skin to get an insight into its skin penetration enhancement mechanism. Acetic acid induced writhing test was performed to evaluate the analgesic effect. Drug concentration-time profile of MLX in rat plasma and skin after topical and oral treatment with MLX-NLC gel and oral MLX-solution, respectively, was observed. MLX-NLC gel was subjected to primary skin irritation test, sub-acute dermal toxicity study. Storage stability of MLX-NLC gel was also assessed for 90 days.

Key findings: NLC gel was effective in permeating Rhodamine 123 to deeper layers of rat skin. Changes in skin lipid prolife were observed in the rat skin on treatment with MLX-NLC gel and the results supported skin lipid extraction as a possible penetration enhancement mechanism. MLX-NLC gel demonstrated sustained pain inhibitory effect. Pharmacokinetics study established that topical application of MLX-NLC gel had the potential to avoid systemic uptake and hence the risk of systemic adverse effects. MLX-NLC gel demonstrated good skin tolerability and biosafety. Excellent physical stability of nanogel was observed at 4?±?2?°C.

Significance: The study revealed that NLC gel is a promising carrier system for the topical application of MLX without side effects.     

Engineering New Microvascular Networks On-Chip: Ingredients,Assembly, and Best Practices

Tissue engineered grafts show great potential as regenerative implants for diseased or injured tissues within the human body. However, these grafts suffer from poor nutrient perfusion and waste transport, thus decreasing their viability post-transplantation. Graft vascularization is therefore a major area of focus within tissue engineering because biologically relevant conduits for nutrient and oxygen perfusion can improve viability post-implantation. Many researchers used microphysiological systems as testing platforms for potential grafts owing to an ability to integrate vascular networks as well as biological characteristics such as fluid perfusion, 3D architecture, compartmentalization of tissue-specific materials, and biophysical and biochemical cues. Although many methods of vascularizing these systems exist, microvascular self-assembly has great potential for bench-to-clinic translation as it relies on naturally occurring physiological events. In this review, the past decade of literature is highlighted, and the most important and tunable components yielding a self-assembled vascular network on chip are critically discussed: endothelial cell source, tissue-specific supporting cells, biomaterial scaffolds, biochemical cues, and biophysical forces. This paper discusses the bioengineered systems of angiogenesis, vasculogenesis, and lymphangiogenesis and includes a brief overview of multicellular systems. It concludes with future avenues of research to guide the next generation of vascularized microfluidic models.     

A Dynamic Inertial Weight Strategy in Micro PSO for Swarm Robots

Wireless Personal Communications - A relatively new area of research and development is Swarm Robotics. It is a part of the swarm intelligence field. In the proposed paper, we shall use swarm...     

Cross-Layer Energy Based Clustering Technique for Heterogeneous Wireless Sensor Networks

Wireless Personal Communications - Effect of combination of dual split ring resonator and electromagnetic bandgap structures over substrate integrated waveguide and half-mode substrate integrated...     

A Novel Self-Organizing Approach to Automatic Traffic Light Management System for Road Traffic Network

Wireless Personal Communications - Traffic network is basically a “network of networks” consisting of mainly two types of networks: road network and a travel network. Due to drastic...