In this paper, Fe–B amorphous submicrometer particles with a size of 180 nm were synthesized by liquid phase reduction method. The as-synthesized Fe–B amorphous submicrometer particles were annealed at 400, 500, and 600 °C, respectively. The effect of annealing temperature on structure, magnetic properties, and microwave absorption properties of Fe–B submicrometer particles was investigated. Results show that the as-synthesized Fe–B amorphous submicrometer particles were crystallized into Fe2B phase when the annealing temperature was 479 °C. The microwave absorption properties of Fe–B submicrometer particles were dependent on annealing temperature, the paraffin composites containing 60 wt% Fe–B submicrometer particles annealed at 500 °C showed a minimal reflection loss (RL) as low as −43.16 dB at 3.12 GHz with a thickness of 5.1 mm, and the effective microwave absorption (RL < −20 dB) was obtained in a wide frequency range of 2.28–10.48 GHz by adjusting the thickness from 1.8 to 6 mm, indicating excellent electromagnetic absorption properties.

Statistical distribution of grid indentation data measured in multiphase materials can be significantly affected by the presence of an interface between adjacent materials. The influence of an interface on the distribution of measured indentation moduli was therefore characterized in model metal–metal, ceramic–ceramic, and metal-ceramic composites. The change of properties near the interface was simulated by finite element method and experimentally verified by indentation in proximity of the boundary between two phases with distinctly different mechanical properties varying the depth of penetration and the distance from the interface. Subsequently, the conditional probability of measuring near the interface was quantified by beta distribution function with parameters dependent on the size of the volume/area affected by the presence of the interface. Using this approach, the intrinsic properties of the individual materials were successfully extracted from the experimental grid indentation data.

Experimental studies have shown capacity loss and impedance rise on the surfaces of cathode particles during (dis)charging in lithium-ion batteries. However, there are surprisingly few studies focusing on the cathode–electrolyte interface. The current study uses multiphysics finite element models to understand fluid–structure interactions in a half-cell battery system. Effects of C-rate, particle sizes, lithiation, and phase transformation of the cathode at the interface are investigated. Results demonstrate that doubling the particle size results in larger available lithium intercalation areas, giving rise to increased tension 1.40 times and compression 1.82 times at the interface. Moreover, higher C-rate with high lithium-ion concentration gradient results in higher mechanical stresses at the interface. These coupling factors are strongly related to the experimentally observed battery degradation. Our simulations demonstrate that both electrode and electrolyte have pronounced effects when investigating mechanical stresses at the electrode–electrolyte interface.

The NaLa(MoO4)2:Yb3+/Er3+ phosphor is synthesized through hydrothermal method with the further calcinations. The intense green upconversion (UC) emission is observed when it is excited by 980 nm pump power. Then we investigate the mechanism of UC emission based on the power dependent upconversion luminescence (UCL) spectra. Temperature sensing performance based on the Stark levels (2H11/2/4S3/2) of Er3+ is estimated through investigating temperature-dependent UCL spectra from 298 K to 573 K. And the maximum value of sensor sensitivity based on FIR is approximately 0.00474 K−1. Moreover, the variations of UCL intensities from 2H11/2/4S3/2 → 4I15/2 transitions have been monitored with increasing pump power, which suggests that the pump energy can be absorbed by sample and heat it. In addition, the internal temperature of materials can be estimated by FIR technique. All the experimental results indicate that the phosphor has good potential in optical temperature sensing and optical heating.

The potency of many biomedical applications of gold nanoparticles (AuNPs); i.e., (i) bioimaging, (ii) diagnostic, (iii) therapeutic, (iv) drug carriers, and (v) immunochemical properties; are limited due its sensitivity toward salt and pH allowing variation in nanogeometry during practical applications. Such limitations directed the synthesis of AuNPs having extreme salt and pH resistant ability which has been undertaken in current research program. It has been found that the pH and salt tolerance ability of AuNPs are dependent on the nature of reducing and stabilizing agents. The use of organic amine containing reagents, i.e., polyethylenimine, 3-aminopropyltrimethoxysilane, in the presence of formaldehyde is examined that allows controlled and rapid synthesis of AuNPs having salt and pH tolerance ability. The mechanism justifying these properties of as-made AuNPs are presented herein. These reagents not only allow the synthesis of monometallic nanoparticles (NPs) but also enable the synthesis of bimetallic and trimetallic NPs. The synthesis of Au–Ag/Ag–Au, Pd-Au/Ag@(PdAu) NPs are examined involving the contribution of organic amine.

A series of novel KLaSr3−x (PO4)3F:xEu2+ phosphors were synthesized for the first time. The crystal structure, photoluminescence properties, concentration quenching, decay analysis, and the temperature dependent luminescence properties were investigated in detail. The unit cell parameters for KLaSr3(PO4)3F were estimated to be a = 9.8997 Å, c = 7.4075 Å, and V = 628.7 Å3. The photoluminescence excitation spectrum of KLaSr3(PO4)3F:Eu2+ shows a broad band from 225 nm to 450 nm with a maximum at about 320 nm. KLaSr3−x (PO4)3F:xEu2+ phosphors exhibit a wide emission band ranging from 425 to 550 nm. KLaSr3(PO4)3F:Eu2+ phosphors exhibit good thermal stability up to 423 K. KLaSr3(PO4)3F:Eu2+ was fabricated with commercial green (Ba,Sr)SiO4:Eu2+ and red CaAlSiN3:Eu2+ phosphors to obtain a white-light-emitting diode. All the results demonstrate that KLaSr3(PO4)3F:Eu2+ are promising blue phosphors for white-light ultraviolet light-emitting diode applications.

The effects of W, Re, Cr, and Mo on microstructural stability, such as the morphology of γ′ phase and the topologically close-packed (TCP) phase precipitation are systematically investigated in eleven kinds of Ni-based single crystal superalloys containing certain amounts of Co, Al, and Ta. After heat treatment, all the designed alloys show different sizes of γ′ phases with typical cuboidal morphology occupying 75% of the total volume. With increasing Re content, the size of γ′ decreases obviously, while the size of γ′ decreases slightly with increasing Cr and Mo contents. Increasing W does not affect the size of γ′. As a result of thermal exposure at 1000 °C for 1000 h, some acicular, rod-like, and blocky TCP phases are precipitated in most alloys. It is noted that Mo and Re can strongly promote the precipitation of TCP phase, but W has no obvious effect on TCP phase precipitation. In addition, transmission electron microscope analysis indicates that these TCP phases are σ phase, μ phase, and R phase.

In this study, we used thermo–mechanical control process (TMCP) technique to investigate the effect of arisen dislocation density and texture components on hydrogen induced cracking susceptibility in as-received API X60 pipeline steel. Dislocations and texture components appeared during cold rolling and annealing treatments. X-ray diffraction and electron backscatter diffraction measurements were used to study these phenomena. We observed that the cold rolling and annealing treatments produced higher dislocation density in deformed and recovered regions. The increase of dislocation density also caused the increased hydrogen trap density. Macro-texture studies by x-ray method indicates that initial weak texture of as-received X60 steel was changed from ζ-fiber to γ-fiber and θ-fiber in 90% cold rolled and annealed specimen. Therefore, the number of grains with 〈100〉||ND orientation which had a harmful effect on hydrogen induced cracking susceptibility increased. The {100} dominant texture and high density of hydrogen traps mitigated against any possible benefits of the other microstructural parameters such as coincidence site lattice boundaries and grain size. As a result, we could not consider this process as a suitable method to increase hydrogen induced cracking resistance in pipeline steel.

Polyaniline (PANI)/11% Multi-carbon nanotubes (MWCNT) nanocomposites sensors were synthesized through an in situ polymerization method. Frits compression method was adopted to make PANI/MWCNT. Transmission Electron Microscopy (TEM) and Scanning Electron Microscopy (SEM) tests results showed that this technique produced a coating of PANI onto the MWCNT, which indicated that CNT were well dispersed in the polymer matrix. Several tests were run to evaluate the sensor's capabilities. The free end vibration test results showed that the double sided attachment of the sensor had higher damping ratio values than single sided attachment. Also, damping ratios were higher when the sensor was placed at the clamped end. Further, the strain sensing properties of PANI/MWCNT sensors were compared with the conventional foil strain gage. The dynamic sensing test results showed that over the range of 10–1000 Hz, the PANI/MWCNT composite sensor was consistently superior to the traditional foil strain gage for sensing purposes.