•Mn0.5Zn0.5Fe2O4-PbZryTi1-yO3 multiferroic fluids were prepared by the ball milling method.•The polarization intensity of PbZryTi1-yO3 particles reaches its maximum of 2.55 μC cm−2.•Aa high ...dielectric constant of 4.6 and a saturation polarization intensity of 15.69 nC cm-2 were obtained.•All specimens present obvious magnetodielectric response.•The maximum longitudinal magnetoelectric coupling coefficient αE33 is 11.49 V cm−1 Oe-1.
The Mn0.5Zn0.5Fe2O4-PbZryTi1-yO3 multiferroic fluids were prepared by the ball milling method, and the polarization intensities of PbZryTi1-yO3 particles on the magnetoelectric coupling (ME) effect were investigated. X-ray diffraction analysis (XRD) results indicate that the pure phase Mn0.5Zn0.5Fe2O4 and PbZryTi1-yO3 particles (y = 0, 0.25, 0.5, 0.75, and 1) were successfully prepared. When y = 0.5, the polarization intensity of PbZryTi1-yO3 particles reaches its maximum of 2.55 μC cm−2. At this time, the Mn0.5Zn0.5Fe2O4-PbZryTi1-yO3 multiferroic fluids possess a high dielectric constant of 4.6 and a saturation polarization intensity of 15.69 nC cm−2. After applying the magnetic field, it shows a better magnetodielectric response (56.12 %), while the ferroelectric properties are also significantly improved. When the polarization intensity reaches its maximum value, the maximum longitudinal magnetoelectric coupling coefficient αE33 is 11.49 V cm−1 Oe-1. It provides a new approach to achieving the strong magnetoelectric coupling effect in multiferroic fluids.
This paper presents a fabrication and evaluation case study of a full-scale multi-material automotive semi-monocoque prototype. The prototype is composed of Variable Axial Composites (VAC) and ...aluminum inserts fabricated using nano-unevenness anodizing bonding technology. The basic design process involves multi-material anisotropic topology optimization and interpretation as manufacturing data. The 3D mold shape is manually defined and developable preform surfaces are placed to fill the mold cavity. The fiber path is automatically generated using the Turing Pattern algorithm based on the optimization data. The preforms are fabricated using the Tailored Fiber Placement (TFP) process, which uses a CNC embroidery machine to realize local fiber orientation control. The preforms are stacked in the mold and molded together with aluminum components by Vacuum Assisted Resin Transfer Molding (VaRTM). Experimental evaluations were conducted to assess the static stiffness of the prototype, and the results are compared with a conventional aluminum design.
•Scheffler reflector is used for fast water production.•Composite desiccant material LiCl/sand, CaCl2/sand & LiBr/sand have been used.•Absorption rate and regeneration rate are carried out for water ...production.•115 ml/day of water can be produced from CaCl2/sand.
In this manuscript, experimental investigations have been performed in order to generate water from atmospheric air by using different composite materials under atmospheric condition of NIT, Kurukshetra, Haryana, India 29°58′ (latitude) North and 76°53′ (longitude) East. In this analysis, three composite materials named LiCl/sand(CM-1), CaCl2/sand(CM-2) and LiBr/sand (CM-3) have been used as salt with 37% concentration and sand as a host material. The absorption and regeneration processes have been performed to generate water from atmospheric air. The absorption process has been carried out at night in the open atmosphere whereas regeneration process took place during the day time by using newly designed 1.54 m2 Scheffler reflector. The maximum amount of water generated from CM-1, CM-2 and CM-3 are 90 ml/day, 115 ml/day and 73 ml/day in 330 min, 270 min and 270 min respectively and the annual cost of water generation are $0.71, $0.53 and $0.86 respectively.
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•Ligand coated porous composite material was synthesized for selective Cd(II) capturing.•The material was exhibited significant color upon addition of trace-level Cd(II) ion.•The ...material was shown high sensitivity and selectivity towards the Cd(II) ions.
Cadmium (Cd(II)) ion is one of the most important toxic metals to remove from contaminated water for safe-guarding the public health. Elevated levels of Cd(II) ion in natural water may have a detrimental effect on both human health, environment and the eco-system. The functionalized materials have been investigated widely over the years for numerous uses to exert a considerable technological impact on future miniaturized, compact, cost effective, and efficient devices. From this point of view, the functional ligand based composite material was fabricated based on the direct anchoring methods for effective Cd(II) ion detection and removal from wastewater. The significant color was visualized upon addition of Cd(II) ion at optimum condition. The optimum pH was carefully evaluated, and pH 5.50 was selected based on the sensitivity, selectivity and color formation. The detection limit was 0.37 μg/L, which was lower than the permissible limit of Cd(II) ion in water. The variable experimental parameters such as solution pH, initial concentration, contact time and foreign ions were systematically evaluated both in monitoring and adsorption operations. The adsorption data were well fitted to the Langmuir adsorption model, and the maximum adsorption capacity was 186.36 mg/g. In the presence of competing ions, the Cd(II) detection and adsorption were not affected due to the specific binding affinity between the composite material and Cd(II) ions. The adsorb Cd(II) ion was desorbed from the composite material using 0.15 M HCl, and the material were simultaneously regenerated into the initial form for the next cycle use without loss the functionality.
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Dye encapsulated metal-organic framework (MOF) composites have emerged as one of the promising platforms toward chemical recognition. Herein, a highly potent hydrolytically stable ...luminescent sensory probe was crafted exhibiting selective fluorescence response for Fe3+ ions in water medium. Encapsulation of a cationic dye inside a porous anionic MOF was successfully achieved via an ion-exchange process. Confinement of dye molecules inside the MOF serving as a crystalline flask prohibits the aggregation-induced quenching of dye molecules thereby manifesting a Dye@MOF luminescent composite material. The Dye@MOF composite shows selective response toward Fe3+ ions with remarkable luminescence quenching even in presence of other metal ions. Additionally, a high Ksv (quenching coefficient) value of 5.5 × 104 M−1 and low limit of detection (LOD) of 1.1 ppm was observed for Fe3+ ions.
In our efforts to obtain electrocatalysts with improved activity for water splitting, meticulous design and synthesis of the active sites of the electrocatalysts and deciphering how exactly they ...catalyze the reaction are vitally necessary. Herein, we report a one‐step facile synthesis of a novel precious‐metal‐free hydrogen‐evolution nanoelectrocatalyst, dubbed Mo2C@NC that is composed of ultrasmall molybdenum carbide (Mo2C) nanoparticles embedded within nitrogen‐rich carbon (NC) nanolayers. The Mo2C@NC hybrid nanoelectrocatalyst shows remarkable catalytic activity, has great durability, and gives about 100 % Faradaic yield toward the hydrogen‐evolution reaction (HER) over a wide pH range (pH 0–14). Theoretical calculations show that the Mo2C and N dopants in the material synergistically co‐activate adjacent C atoms on the carbon nanolayers, creating superactive nonmetallic catalytic sites for HER that are more active than those in the constituents.
Hybrid catalyst: An efficient hybrid hydrogen‐evolution electrocatalyst containing molybdenum carbide nanoparticles embedded in nitrogen‐rich carbon nanolayers has been synthesized in one‐step from inexpensive precursors. The synergistic effect between Mo2C and N dopants was found to yield very active nonmetallic HER catalytic sites on the carbon nanolayers.
Airplanes are inevitably subjected to various impact loading conditions in the event of emergency landing. An airplane crash scenario is a complex nonlinear impact event which involves large ...deformation, material fracture, structural failure, and dynamic contact. The impact response becomes more complicated due to the presence of composite materials, which are becoming the dominated choice for aircraft components. However, the impact damage and failure severity of composite fuselage sections can be effectively alleviated with optimized energy absorbing (EA) design. Accordingly, the crashworthy design of fuselage sections has always remained a top priority to prevent catastrophic structural failure and significant casualties. This paper presents a systematic literature review on the impact response and EA design of composite fuselage structures. Firstly, the typical composite materials such as composite tubes, corrugated composite plates, hybrid composite structures and bio-inspired composite materials are introduced to dissipate the impact kinetic energy during a crash. Then, the analytical models and finite element modeling methods of composite bolted joint structures are described to investigate their impact response and failure mode. The crashworthy design of typical composite fuselage structures including sub-cargo support struts, cabin floor support struts, fuselage frame and cabin floor/fuselage frame connection are described in this paper. Finally, an emphasis is placed on the evaluation criteria of the occupant crash safety and the crashworthy evaluation method of fuselage structures.
We propose a weak form of the transient heat equations for solid bodies, as a time-dependent spatial variation of the heat displacement vector field, whose time derivative is the heat flux. This ...develops the variational principle originally proposed by Biot, inasmuch Fourier’s law is embedded as a holonomic constraint, while energy conservation results from the variation (the vice-versa from Biot). This is a neat formulation because only the heat displacement appears in the variational equations, whereas Biot’s form also involved the unknown temperature field: Fourier’s law is used only a posteriori to recover the temperature. Since the heat displacement is generally more regular than the temperature field, it represents a natural variable in problems with material inhomogeneities, uneven radiation, thermal shocks. The three-dimensional analytical set-up is presented in comparison with Biot’s, for boundary conditions accounting for radiation and convection. A mechanical analogy with the equilibrium of an elastic bar with viscous constraints is suggested for the one-dimensional case. The variational equations are implemented in a finite element code. Numerical experiments on benchmark problems, involving high temperature gradients, confirm the efficiency of the proposed approach in many structural problems.
