Developing Robust FeSiAl/PEEK Composites for Wide-Temperature-Range Electromagnetic Wave Absorption.

Presently, researchers are placing emphasis on microwave absorption coating design while neglecting the research on materials that integrate both microwave absorption performance and mechanical properties. Here, robust FeSiAl/PEEK composites were prepared by a series process, including post ball-milling annealing, sol-gel method, and hot pressing. A detailed analysis of the electromagnetic (EM) parameters reveals the significant effects of morphology, filling ratio, and microstructure of FeSiAl on EM losses under a wide-temperature range.

Unveiling the sp ─sp C─C Polar Bond Induced Electromagnetic Responding Behaviors by a 2D N-doped Carbon Nanosheet Absorber.

The infertile electromagnetic (EM) attenuating behavior of carbon material makes the improvement of its performance remain a significant challenge. Herein, a facile and low-cost strategy radically distinct from the prevalent approaches by constructing polar covalent bonds between sp -hybridized and sp -hybridized carbon atoms to introduce strong dipolar polarization is proposed. Through customizing and selectively engineering the N moieties conjugated with carbon rings, the microstructure of the as-synthesized 2D nanosheet is gradually converted with the partial transition from sp carbons to sp carbons, where the electric dipoles between them are also tuned.

Influence of the laser pulse time profile on residual stress characteristics in laser shock peening.

In this paper, residual stress and plastic deformation of TC4 titanium alloys and AA7075 aluminum alloys after laser shock peening (LSP) with the laser pulses that have the same energy and peak intensity but different time profiles have been studied. The results show that the time profile of the laser pulse has a significant influence on LSP. The difference between the results of LSP with varying laser input mode has been contributed to the shock wave caused by different laser pulse.

Tunable Photoluminescence Properties of Cotton Fiber With Gradually Changing Crystallinity.

The alkali mercerizing process of semicrystalline cotton fiber (CF) is widely used in the printing and dyeing industry. The crystallinity change in the mercerizing process has been studied and certain laws have been obtained, but there is still a certain distance between the theoretical research results and the practical applications. CF is almost composed of cellulose, combined with the photoluminescence (PL) phenomenon of cellulose; herein, the varying crystallinity is correlated with its PL behavior after being treated with different concentrations of NaOH.

Highly efficient heterogeneous photo-Fenton BiOCl/MIL-100(Fe) nanoscaled hybrid catalysts prepared by green one-step coprecipitation for degradation of organic contaminants.

An excellent heterojunction structure is vital for the improvement of photocatalytic performance. In this study, BiOCl/MIL-100(Fe) hybrid composites were prepared a one-pot coprecipitation method for the first time. The prepared materials were characterized and then used as a photo-Fenton catalyst for the removal of organic pollutants in wastewater.

Tunable Photoluminescence Properties of Microcrystalline Cellulose with Gradually Changing Crystallinity and Crystal Form.

Nonconventional luminogens with persistent room temperature phosphoresce (p-RTP) are attracting increasing attention owing to their momentous significance and diverse technical applications in optoelectronic and biomedical. So far, the p-RTP emission of some amorphous powders or single crystals has been studied in depth. The p-RTP emission of amorphous and fully crystalline states and their emission properties are widely divergent, while the difference of their p-RTP emission mechanism is still controversial.

Precipitation during Quenching in 2A97 Aluminum Alloy and the Influences from Grain Structure.

The quench-induced precipitation and subsequent aging response in 2A97 aluminum alloy was investigated based on the systematic microstructure characterization. Specifically, the influence on precipitation from grain structure was examined. The results indicated the evident influence from the cooling rate of the quenching process.

Effect of Pre-Stretch on the Precipitation Behavior and the Mechanical Properties of 2219 Al Alloy.

The influence of pre-stretch on the mechanical properties of 2219 Al alloys sheets were systematically investigated, with the aim of examining the age-strengthening in parts draw-formed from as-quenched sheets. The precipitation was characterized based on differential scanning calorimetry (DSC) analysis and transmission electron microscope (TEM) observation of specimens of as-quenched and quenched-stretched condition to address the influence of pre-stretching. A tensile test was performed to evaluate the effect on mechanical properties.

Porous Film Coating Enabled by Polyvinyl Pyrrolidone (PVP) for Enhanced Air Permeability of Fabrics: The Effect of PVP Molecule Weight and Dosage.

This study developed a versatile and facile method for creating pores and tuning the porous structure in the polymer latex films by selectively etching the added functional polyvinyl pyrrolidone (PVP) molecules. The pore formed in the latex films had a similar morphology to that of PVP aggregation before etching. This observation promotes us to regulate the pore morphology that determines the film's property, such as air permeability through varying the PVP molecule weight and dosage.

Sandwich-like cobalt/reduced graphene oxide/cobalt composite structure presenting synergetic electromagnetic loss effect.

The poor dispersity and oxidation resistance of ferromagnetic metal nanoparticles can induce serious deterioration in electromagnetic properties, which then significantly limits the application of this catalog of materials. In this work, sandwich-like Co/rGo/Co composites were in situ constructed, in which monodispersed Co nanoparticles with diameters of 20-60 nm were densely dispersed on both sides of rGO nanosheets. A connecting network between the densely-packed Co nanoparticles can be formed, where Co nanoparticles are abutted or bridged to each other through a neck of Co.

Carbon-coated CoFe-CoFeO composite particles with high and dual-band electromagnetic wave absorbing properties.

SiO and TiO, as conventional dielectric shells of ferromagnetic/dielectric composite particles, can protect ferromagnetic particles from aggregation and oxidation, but contribute little to electromagnetic loss. In this work, we designed nano-assembled CoFe-CoFeO@C composite particles, in which ferrites with high permeability were dielectric elements and carbon was introduced as protective layers, aiming for high-efficiency microwave absorption. These assembled particles with different CoFe contents were prepared through solvothermal methods and subsequent hydrogen-thermal reduction.

Rational Construction of Uniform CoNi-Based Core-Shell Microspheres with Tunable Electromagnetic Wave Absorption Properties.

Core-shell particles with integration of ferromagnetic core and dielectric shell are attracting extensive attention for promising microwave absorption applications. In this work, CoNi microspheres with conical bulges were synthesized by a simple and scalable liquid-phase reduction method. Subsequent coating of dielectric materials was conducted to acquire core-shell structured CoNi@TiO composite particles, in which the thickness of TiO is about 40 nm.

CoFe and CoFe@SiO Nanospheres with Tunable Diameters for High-Performance Electromagnetic Wave Absorption.

Ferromagnetic metal/alloy nanoparticles have attracted extensive interest for electromagnetic wave-absorbing applications. However, ferromagnetic nanoparticles are prone to oxidization and producing eddy currents, leading to the deterioration of electromagnetic properties. In this work, a simple and scalable liquid-phase reduction method was employed to synthesize uniform CoFe nanospheres with diameters ranging from 350 to 650 nm for high-performance microwave absorption application.

Synthesis of Zn(II)-Doped Magnetite Leaf-Like Nanorings for Efficient Electromagnetic Wave Absorption.

We report the thermal annealing-induced formation of ring-like structure of Zn(II)-doped magnetite from iron alkoxide leaf-like nanoplate precusor. The phase, structure and morphology of magnetite nanorings were comprehensively characterized by powder X-ray diffraction, X-ray photoelectron spectroscopy, atomic force microscope, scanning electron microscope, and transmission electron microscope. The obtained Zn(II)-doped magnetite nanorings are of 13-20 nm in edge width, 70-110 nm in short axis length and 100-150 nm in long axis length.