For the first time in the literature, experimental determination of entire sets of exact interdiffusion coefficients in quaternary and quinary alloy systems is reported. Using the method of body-diagonal diffusion couple, a set of nine quaternary interdiffusion coefficients were evaluated in Fe–Ni–Co–Cr and a set of sixteen quinary interdiffusion coefficients were determined in a Fe–Ni–Co–Cr–Mn system, both at approximately equimolar compositions. Regions of uphill interdiffusion and zero flux planes were observed for nickel and cobalt in quinary couples, indicating the existence of strong diffusional interactions in Fe–Ni–Co–Cr–Mn alloys. The strong diffusional interactions were also manifested in the large magnitudes of cross coefficients in both the systems. The existence of strong diffusional interactions in high-entropy alloys (HEAs) as observed through experimentally determined interdiffusion coefficients in this study establishes beyond doubt the fact that cross interdiffusion coefficients cannot be ignored in HEAs.

Graphene-based flexible and wearable supercapacitors have been produced by wetspinning, in which organic solvent coagulating bath was prerequisite and spacerswere usually incorporated to improve the electrochemical property butsacrificing the mechanical property. In this work, a nonorganic solvent spinningtechnology named as interfacial polyelectrolyte complexation (IPC), which wasbased on the spontaneous self-assembly of two oppositely charged polyelectrolytesolutions/suspensions to form continuous fibers on drawing in their interfaces,was proposed to fabricate graphene fiber–shaped electrodes forsupercapacitors. Due to the excellent mechanical performance and hydrophilicity,cellulose nanofibrils (CNFs) were added to serve as an efficient reinforcingagent and spacer of graphene fiber electrodes. Consequently, the mechanicalperformance and specific capacitance of the fibers were improved but electricalconductivity was declined. Taking overall consideration, CNF/rGO60 fiberelectrode possessed a superior integrated performance with a capacitance of182.6 F/g, tensile strength of 480 MPa, and electrical conductivity of 5538.7S/m. The IPC spinning provided an environmentally friendly strategy for thefabrication of fiber-shaped functional devices.

The authors propose an alternative route to circumvent the limitation of neutron flux using the recent deep learning super-resolution technique. The feasibility of accelerating data collection has been demonstrated by using small-angle neutron scattering (SANS) data collected from the EQ-SANS instrument at Spallation Neutron Source (SNS). Data collection time can be reduced by increasing the size of binning of the detector pixels at the sacrifice of resolution. High-resolution scattering data is then reconstructed by using a deep learning-based super-resolution method. This will allow users to make critical decisions at a much earlier stage of data collection, which can accelerate the overall experimental workflow.

The thermal expansion coefficient (TEC) of nano-B4C having 50 nm mean particle size was measured as a function of applied direct current (DC) electric field strength varying from 0 to 12.7 V/mm and over a temperature range from 298 K up to 1273 K. The TEC exhibits a linear variation with temperature despite being measured over a range that is well below 50% of B4C’s normal melting temperature. The zeroth- and first-order TEC coefficients under zero-field condition are 4.8220 ± 0.009 × 10−6 K−1 and 1.462 ± 0.004 × 10−9 K−1, respectively. Both TECs exhibit applied DC electric field dependence. The higher the applied field strength, the steeper the linear thermal expansion response in nano-B4C, which suggests that the applied field affects the curvature of the interatomic potentials at the equilibrium bond length at a given temperature. No anisotropic thermal expansion with and without applied electric field was observed, although nano-B4C has a rhombohedral unit cell symmetry. The rhombohedral unit cell angle was determined as δR= 65.7046° (0.0007), and it remains unaffected by a change in temperature and applied electric field strength, which we attribute to B4C nanoparticle size and its carbon saturation.

Microstructural evolution of Cu–Nb oxide nanocomposite alloys during ball milling is investigated using a two-step ball-milling approach. In the first step, Cu and Nb powders are milled to create a two-phase alloy comprising a Cu-rich matrix containing a high density of 20- to 30-nm Nb precipitates. In the second step, this nanocomposite is co-milled with CuO, resulting in the reduction of CuO and the oxidation of the Nb nanoprecipitates. Transmission electron microscopy characterization shows that three distinct types of Nb oxide precipitates evolve at different levels of strain. First, nanocrystalline NbO particles (∼10 nm) are formed by dissolved Nb in Cu reacting with oxygen evolved from the CuO. Next, the Nb nanoprecipitates in Cu further reduce CuO to form Nb/Nb oxide and NbO/Nb oxide core–shell inclusions (20–30 nm). These inclusions coalesce during additional milling to form amorphous Nb oxide agglomerates (>700 nm after 50 h). The growth of Nb precipitates during step-one milling, the initial growth of NbO nanoparticles, and the formation of core–shell Nb oxide precipitates during step-two milling are attributed to the convective transport of atoms and clusters combined with shear-induced agglomeration.

SiC and Ga2O3 are promising wide band gap semiconductors for applications in power electronics because of their high breakdown electric field and normally off operation. However, lack of a suitable dielectric material that can provide high interfacial quality remains a problem. This can potentially lead to high leakage current and conducting loss. In this work, we present a novel atomic layer deposition process to grow epitaxially MgxCa1−xO dielectric layers on 4H-SiC(0001) and β-Ga2O3$\left( {\bar 201} \right)$ substrates. By tuning the composition of MgxCa1−xO toward the substrate lattice constant, better interfacial epitaxy can be achieved. The interfacial and epitaxy qualities were investigated and confirmed by cross-sectional transmission electron microscopy and X-ray diffraction studies. Mg0.72Ca0.28O film showed the highest epitaxy quality on 4H-SiC(0001) because of its closest lattice match with the substrate. Meanwhile, highly textured Mg0.25Ca0.75O films can be grown on β-Ga2O3$\left( {\bar 201} \right)$ with a preferred orientation of (111).

Nanocomposites of polyvinylidene fluoride loaded with various amounts of γ-Fe2O nanoparticles, with an average size ranging between 20 and 40 nm, have been obtained by melt mixing and investigated using various experimental techniques [Superconducting Quantum Interference Device, Mössbauer, and Thermogravimetric Analysis]. Magnetic and Mössbauer measurements confirmed the presence of maghemite and a trace of a paramagnetic iron compound. Magnetic data are consistent with a blocking temperature close to room temperature (RT), showing a decrease in the coercive field as the temperature is increased. A weak exchange bias was noticed in all nanocomposites investigated at all temperatures and tentatively ascribed to surface spin disorder. The temperature dependence of the coercive field obeys the Kneller law. The nanocomposites exhibit superparamagnetic behavior near RT. Most magnetic measurements have been performed below the blocking temperature, revealing thus a complex behavior. The dependence of the mass loss derivative versus temperature, as obtained by thermogravimetric analysis, exhibits a single peak due to the thermal degradation of the polymeric matrix. A weak increase in the thermal stability of the polymeric matrix upon loading with maghemite is reported.

This work focuses on the functionalization of agave xylan-type hemicellulose functionalized with trimethoxysilylpropylmethacrylate and crosslinked with N-vinylcaprolactam to obtain a thermoresponsive material for potential applications in drug delivery. The hydrogels showed an interconnected and porous architecture with a lower critical solution temperature (LCST) close to poly(N-vinylcaprolactam)’s (PNVCL) LCST. These materials showed a good capacity to load ciprofloxacin (in the range 9.5 × 10−3–8.4 × 10−3 mg/mL), above the minimum inhibitory concentration (MIC ≤ 0.004 × 10−3–0.5 × 10−3 mg/mL) for gram-positive and gram-negative bacteria. The hybrid hydrogel inhibited the growth of Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa.