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The functional films based on chitosan and corn starch incorporated tea polyphenols were developed through mixing the chitosan and starch solution and the powder of tea polyphenols by the casting method. The objective of this research was to investigate the effect of different concentrations of tea polyphenols on the functional properties of the films. Attenuated total reflectance Fourier transform infrared spectrometry and X-ray diffraction were used to investigate the potential interactions among chitosan, corn starch and tea polyphenols in the blend films. Physical properties of the blend films, including density, moisture content, opacity, color, water solubility and water swelling, as well as morphological characteristics, were measured. The results demonstrated that the incorporation of tea polyphenols caused the blend films to lead to a darker appearance. The water solubility of the blend film increased with the increase of tea polyphenol concentrations, while moisture content and swelling degree decreased. The hydrogen bonding between chitosan, starch and tea polyphenols restricted the movement of molecular chains and was helpful to the stability of the blend films. The results suggested that these biodegradable blend films could potentially be used as packaging films for the food and drug industries to extend the shelf life to maintain their quality and safety.

Waste rubber wood (RW) is the castoff of rubber plantation with abundant reservation but without high-value utilization. In this study, cellulose with high purity has been efficiently isolated from waste RW and further processed into cellulose nanocrystals. By means of acetylation, more hydrophobic cellulose-based products, namely acetylated rubber wood cellulose (Ac–RWC) and acetylated rubber wood cellulose nanocrystals (Ac–RW–CNC) had been attempted as reinforcing fillers for fabricating two series of PLA-based composite films via spin coating instead of currently prevailing melt compounding technique. To ensure a uniformed dispersion of fillers in PLA matrix, the addition of reinforcing filler should be equal to or less than 5% based on the film dry weight. Compared with pure PLA film, the Ac–RWC reinforced PLA composite films are more thermally stable, while the Ac–RW–CNC reinforced PLA composite films on the other hand exhibit more enhanced performance in mechanical properties and the degree of crystallinity. The highest tensile strength (55.0 MPa) and Young’s modulus (3.9 GPa) were achieved for 5%Ac–RW–CNC/PLA composite film.

The Heusler-type spin gapless semiconductors (SGSs) have been extensively studied owing to their characteristic band structure, i.e., zero band gap of majority electrons and clear band gap of minority electrons. To date, the intrinsic physical property of the correlated single crystal is somewhat unclear, leading to difficulty in understanding the principle physical mechanism. In this study, we successfully fabricated the single crystal of the potential spin-gapless semiconductor Heusler CoFeMnSi compound and investigated its intrinsic physical properties. The saturation magnetization of the single crystal at 50 K is ∼99.55 emu/g (∼3.53 μB/f.u.), and the single crystal exhibits a Curie temperature of 826 K. The resistivity of single crystal shows anisotropy: the temperature dependence of resistivity along the [111] direction is completely different from the behavior along [001] and [100] directions. Furthermore, when the temperature was >135 K, a semiconductor-like behavior was observed along the [111] orientation.

The influence of Nb substitution on the structure, magnetoelastic transition and magnetocaloric properties has been investigated for the Mn1.1Fe0.85-xNbxP0.43Si0.57 alloys. The substitution for Fe by merely 4.7 at.% Nb (i.e. x = 0.04) significantly diminishes the thermal hysteresis from 10 to 1 K due to the reduced structural discontinuity crossing the magnetoelastic transition. This also improves the mechanical stability. The Curie temperature of the magnetoelastic transition is lowered by approximately 11.6 K per at.% of the Nb substitution, originating from the enhanced covalent bonding that favors the paramagnetic state. The giant magnetocaloric effect is still retained in the Nb-substituted alloys.

Bonded samples of La0.9Ce0.1Fe11.7Si1.3H1.8 and La0.9Ce0.1Fe11.41Mn0.29Si1.3H1.8 with NaZn13-type cubic structure have been prepared, and their mechanical properties and magnetocaloric effects have been investigated. The bonded samples show a very good compressive strength of 320 and 332 MPa, about 10% and 14% higher than that of bulk LaFe10.99Co0.91Si1.1B0.2 compound. By partial substitution of Mn for Fe, the Curie temperature (Tc) of bonded La0.9Ce0.1Fe11.7Si1.3H1.8 decreases remarkably from 325 to 279 K. The magnetic entropy change (ΔSm) for bonded La0.9Ce0.1Fe11.7Si1.3H1.8 and La0.9Ce0.1Fe11.41Mn0.29Si1.3H1.8 slightly reduces compared with hydride alloys, but still maintains large values of 8.8 and 7.9 J/kg K. The two bonded samples exhibit the same adiabatic temperature change (ΔTad) of about 2.6 K under a field change from 0 to 1.5 T. The bonded La0.9Ce0.1(Fe,Mn)11.7Si1.3 hydrides samples with good magnetocaloric effects and better mechanical properties are promising as high performance magnetic refrigerants materials.

The Mn 38 Fe 22 Al 40 C x alloys with x = 0, 0.1, 0.3, 0.5, 0.7, 1.5 and 2.5 were investigated. XRD results show that the alloys with x = 0, 0.1, 0.3, 0.5, 0.7 crystallize in CsCl(B2)-type structure. The alloys with x = 1.5 and 2.5 crystallize in (Fe/Mn) 3 Al(DO 3 ), and there exists an α-Mn phase. The Curie temperature ( T C ) decreases with increasing of carbon content. The maximal magnetic-entropy change is 0.71 J/kg K (0–1.5 T) for x = 0.3 at 297 K, which is 16% higher than that of the parent alloy. The adiabatic temperature change of Mn 38 Fe 22 Al 40 C x alloys was around 0.19 K in 1.5 T.