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Magnetocaloric properties of (La 1- x Nd x) 2 Fe 10.7 Mn 0.3 Si 2 H y (x = 0.1 and 0.2) are evaluated to develop a room-temperature magnetic refrigerant. While Nd which is introduced to reduce the thermal hysteresis has a negligible effect on magnetic properties, the partial replacement of Fe with Mn converted the first-order magnetic transition to a second-order and T C is reduced by 50 K to near room temperature. The peak entropy change, Δ S M | pk values are 10.4 J kg−1 K−1 (at 290 K) for x = 0.1 and 10.6 J kg−1 K−1 (at 286 K) for x = 0.2 with μ 0 ∆ H = 3 T. The maximum values of the adiabatic temperature change, Δ T ad are 4.11 K (at 283 K) for x = 0.1 and 4.05 K (at 289 K) for x = 0.2 with μ 0 ∆ H = 1.4 T. Because T C can be shifted by the addition of Mn to room temperature, this series of compounds can be used as an efficient magnetic refrigerant or a combination as a composite refrigerant for an active magnetic refrigeration cycle. • (La 1- x Nd x) 2 Fe 10.7 Mn 0.3 Si 2 H y was synthesized for room-temperature magnetic refrigeration. • Mn addition reduced thermal hysteresis of hydrogenated La(FeSi) 13 alloys. • The peak Δ S M of LaFeSi-based alloys were measured to be 10.4 J kg−1 K−1 and 10.6 J kg−1 K−1. • Δ T ad of (La 1- x Nd x) 2 Fe 10.7 Mn 0.3 Si 2 H y (x = 0.1 and 0.2) was measured to be 4 K. [ABSTRACT FROM AUTHOR]

The morphological and mechanical characteristics of red blood cells (RBCs) largely vary depending on the occurrence of hematologic disorders. Variations in the rheological properties of RBCs affect the dynamic motions of RBCs, especially their rotational behavior. However, conventional techniques for measuring the orientation of biconcave-shaped RBCs still have some technical limitations, including complicated optical setups, complex post data processing, and low throughput. In this study, we propose a novel image-based technique for measuring 3D position and orientation of normal RBCs using digital in-line holographic microscopy (DIHM) and artificial intelligence (AI). Formaldehyde-fixed RBCs are immobilized in coagulated polydimethylsiloxane (PDMS). Holographic images of RBCs positioned at various out-of-plane angles are acquired by precisely manipulating the PDMS-trapped RBC sample attached to a 4-axis optical stage. With the aid of deep learning algorithms for data augmentation and regression analysis, the out-of-plane angle of RBCs is directly predicted from the captured holographic images. The 3D position and in-plane angle of RBCs are acquired by employing numerical reconstruction and ellipse detection methods. Combining these digital image processing techniques, the 3D positional and orientational information of each RBC recorded in a single holographic image is measured within 23.5 and 3.07 s, respectively. The proposed AI-based DIHM technique that can extract the 3D position, orientation, and morphology of individual RBCs would be utilized to analyze the dynamic translational and rotational motions of abnormal RBCs with hematologic disorders in shear flows through further research. • AI-based analysis of out-of-plane angles of RBCs was demonstrated. • 3D positions and in-plane angles of RBCs were measured using a DIHM technique. • 3D positions and orientations of RBCs recorded in a single hologram were measured. • This technique has a simpler optical setup and higher throughputs than others. • It would be utilized to analyze 3D dynamics of RBCs flowing in a microchannel. [ABSTRACT FROM AUTHOR]

Cobalt hexacyanoferrate (CoHCF) suffers from low rate capability and lifespan because of the dissolution and structural instability of Co during cycling. A smaller active material can relieve the stress caused by volume change during cycling and enable shorter transport pathways. Here, particle size reduction is performed by reducing the mixing time or citrate concentration in the coprecipitation reaction to improve the rate capability and lifespan of CoHCF. The reduced mixing time produces smaller particles with enlarged active sites, thus improving the capacity. Upon coprecipitation at a low citrate concentration, particle precipitation at reduced sizes is achieved by preferential nucleation versus growth. Although lowering the citrate concentration enlarges the external surface area, the reduced redox-active Fe degrades the capacity. All CoHCF samples with small sizes achieved enhance rate capability and stability. In particular, the sample synthesized with a short mixing time (0 h) achieve a specific capacity of 122 mAh g−1 with improved rate capability (79.4%) and stability (79.3%) over 500 cycles. Structural distortions are relaxed because of the shortened transport pathways and relieved distortion owing to particle size reduction. This study paves the approach for fast rechargeable and long-lasting aqueous Na-ion batteries using CoHCF electrodes. [Display omitted] • A decreased mixing time or citrate concentration yielded smaller CoHCF particles. • The capacity, rate capability, and lifespan were improved with shorter mixing times. • The low citrate ion concentration increased Fe vacancies and decreased the capacity. • Fe vacancies limited Na access in the lattice, thus improving structural stability. • The reduced CoHCF particle size improved rate capability and lifespan. [ABSTRACT FROM AUTHOR]

The flexural resistance of fiber reinforced cementitious composites (FRCCs) under biaxial condition was investigated by using two different types of biaxial bending test methods: the biaxial flexural test (BFT) and the centrally loaded round panel test (RPT). The flexural responses of FRCCs under biaxial condition were then compared with those of FRCCs under uniaxial condition; i.e. four-points bending test (4PBT). The test results, including the equivalent biaxial strength and normalized energy absorption capacity of the RPT, were found to be clearly higher than those of the BFT, and completely different cracking behavior was observed between the two biaxial test methods; the BFT generated numerous randomly distributed micro-cracks at the bottom of specimens, whereas the RPT mostly showed three major cracks, with minor radial cracks around them. In addition, the equivalent flexural tensile strength and normalized energy absorption capacity of the FRCCs under biaxial condition were found to be higher than those under uniaxial condition. The energy absorption capacity and the ratio of flexural tensile strength to the direct tensile strength of FRCCs are dependent on the stress state. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fe-AC/Fe 2 O 3 /PVA microgels were manufactured using a microfluidic approach. • The microgels were solidified via Schiff-base and acetalization reactions. • The microgels showed high adsorption selectivity and capacity for anionic dyes. • The microgels maintained a high reusability level of ∼ 85 % after five cycles. • The microgels can be easily recovered by an external magnetic field after adsorption. In this study, magneto-responsive iron-aminoclay/iron oxide/polyvinyl alcohol (Fe-AC/Fe 2 O 3 /PVA) composite microgels were successfully fabricated via a Schiff-base and acetalization reactions using a microfluidic approach. The as-prepared Fe-AC/Fe 2 O 3 /PVA composite microgels were used as adsorbents to remove organic dyes from aqueous solutions. The chemical cross-linking and morphology of the prepared microgel particles were evaluated using Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, optical microscopy, Brunauer–Emmett–Teller surface area analysis, and scanning electron microscopy. The Fe-AC/Fe 2 O 3 /PVA microgels served as an effective adsorbent by exhibiting a remarkable adsorption capacity for anionic dyes such as methyl orange (MO), Congo red (CR), and methyl blue (MB) owing to their fast diffusion kinetics, porous structures, and numerous amino groups. The microgels had maximum adsorption capacities of 457.31 mg/g for MO, 352.88 mg/g for CR, and 566.98 mg/g for MB. The prepared microgels were systematically evaluated for their adsorption behavior toward the anionic dyes from aqueous solutions at various process parameters, such as pH, contact time, and dye concentration. The adsorption process for the anionic dyes fitted well with the pseudo-second-order kinetic model and Sips isotherm model, verifying that the sorption process was mainly governed by chemisorption. Furthermore, the Fe 2 O 3 magnetic nanoparticle incorporation made it simple to separate the microgels from the aqueous solutions and reuse them. The microgels maintained an adsorption efficiency of above 80 % even after five adsorption–desorption cycles. These results demonstrate that the magneto-responsive Fe-AC/Fe 2 O 3 /PVA hybrid microgels are an effective and sustainable adsorbent for treating wastewater contaminated with anionic dyes. [ABSTRACT FROM AUTHOR]