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Four drying methods, hot air drying (HAD), microwave constant temperature drying (MWD), microwave vacuum temperature‐controlled drying (MIVD‐T50), and freeze drying (FD), were investigated for their effects on raspberries in terms of drying time, color, microstructure, rehydration, water activity, phenolic compounds, flavonoids, anthocyanins, and DPPH scavenging ability. It was found that microwaves combined with vacuum took the shortest time. The color of MIVD‐T50 is similar to that of FD and much better than that of HAD and MWD. A smooth surface and fluffy and porous structure inside were observed in the FD and MIVD by scanning electron microscopy (SEM) images. FD has the highest energy consumption, followed by HAD, MIVD‐T50 and MWD. The retention rates of total phenols and flavonoids in HAD, MWD and FD were lower than those in MIVD‐T50, and FD had the advantage of retaining anthocyanin content. In general, MIVD‐T50 has significance for the commercial production of raspberry. Practical applications: The use of natural antioxidants in food processing not only enhances the shelf life of products but also improves their nutritional value. Raspberry is a rich source of antioxidants and is widely used in food processing. However, the drying process is crucial in preserving its antioxidant quality, and different drying methods affect the antioxidant content differently. According to the results of the experiments, the drying method has a considerable impact on the energy usage and quality of dried raspberries. Compared with the HAD and MWD treatments, both FD and MIVD‐T50 showed better nutrient content preservation and antioxidant activity, which may be caused by the lower temperature drying process of FD or the stronger efficiency of MIVD‐T50. However, the drying time of FD is longer, and the energy consumption is higher. Therefore, MIVD‐T50 is a promising raspberry drying technology with low energy consumption, a short drying time, and high quality. It has huge development potential and broad commercial scale production market prospects. [ABSTRACT FROM AUTHOR]

The Cu–Fe metal‐based ceramic grinding wheel material with SiC as abrasive was prepared by the powder metallurgy process of ball milling and hot pressing sintering. Cu–Fe–SiC cermets with Cu:Fe mass ratios of 4:1, 1:1, and 1:4 were designed by changing the composition of metal binder. The phase composition, microstructure, mechanical properties, and grinding properties of Cu–Fe–SiC cermets were systematically studied. The effect of Cu–Fe binder ratio on the microstructure and properties of cermets was analyzed. The results show that with the increase of Fe content, the density and hardness of cermets increase gradually, indicating that the mechanical properties are improved. Because the Fe in the adhesive can react with the abrasive SiC to form the reaction bonding interface, the Cu–80Fe–SiC cermets with higher Fe content have better adherence. The grinding test results of Cu–80Fe–SiC cermet show that the friction coefficient is.341, the surface roughness is 6.64 μm, the residual stresses parallel to the grinding direction are 353.3 MPa, and the residual stresses perpendicular to the grinding direction are 140.9 MPa. With the increase of Fe content, the wear mechanism changes from ploughing and cutting to friction. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cu-Nb composite diffused metal interlayer was first applied to TC4 and 4J36 electron beam welding. • The use of Cu-Nb interlayer produces solid solutions in the two weld melting zones. • The use of Cu-Nb interlayer improves the quality of welded joint between TC4 and 4J36. • The formation mechanism of 4J36/Cu-Nb/TC4 bonded joints was studied. Electron beam welding of 4J36 invar alloy and TC4 titanium alloy was carried out with Cu-Nb composite diffused metal interlayer. The results showed that the depth to width ratio and the tensile strength of welded joints increased with the increase of electron beam current. Under the designed process parameters, two melting zones (MZ) in welded joints formed solid solutions (ss), the welded joint tensile strength reached maximum value of 244.1 MPa, and the fracture location was mainly located at 4J36/Cu interface. [ABSTRACT FROM AUTHOR]

High current pulsed electron beam (HCPEB) technology was applied to irradiate the surface of mono-crystalline Ge wafers (Ge (100) and Ge (111)) with different orientations, and the microstructure and properties of the irradiated surface were analyzed in detail. The results show that after HCPEB irradiation, numerous molten pits and local microcracks were produced on the surface of mono-crystalline Ge, and the pit density decreased with the increase of irradiation pulses. TEM observations indicated that after irradiation, the defects are mainly vacancy group defects and dislocation rings, and Ge nanocrystals with uniform size distribution are produced. HCPEB irradiation also formed self-assembled nanostructures on the surface of Ge. Cross section TEM indicated that the 250 nm deep defect channels were under the quantum dots, which confirms the formation mechanism of self-assembled nanostructures. The photoluminescence results indicated that the irradiated mono-crystalline Ge still has blue emission properties, and the luminescence mechanism is the quantum confinement effect of Ge nanocrystals embedded in slightly oxidized or nitrided amorphous structures. • HCPEB irradiation can induce the proliferation of crystal defects and the formation of neatly arranged microcrack. • HCPEB irradiation induced numerous supersaturated vacancy defects in mono-crystalline Ge. • HCPEB irradiation induced the formation of nanocrystals on the Ge surface. • HCPEB irradiation induced the formation of self-assembled nanostructures on Ge surface. • After HCPEB irradiation, the blue light emission phenomenon of photoluminescence appeared in mono-crystalline Ge. [ABSTRACT FROM AUTHOR]

[Display omitted] • The cryogenic treatment was first applied to TC4/316L diffusion welded joint. • The effect of cryogenic treatment on microstructure of base metal TC4 and 316L was investigated. • The cryogenic treatment improves the quality of dissimilar joint between titanium alloy and stainless steel. • The bonding mechanism of joints and the influence mechanism of cryogenic treatment were analyzed. The diffusion welded joints of 316L/TC4 with Nb/Cu metal interlayer were subjected to cryogenic treatment. After cryogenic treatment, the strength of joints increased with the increase of soaking time. The strength of joints decreased with the increase of the cycle impact times. The average tensile strength of as-welded joints (AW) was 236.7 MPa, and the cryogenic treated samples for 24 h reached the best (280 MPa). The bonding mechanism of TC4/Nb/Cu/316L vacuum diffusion bonding joints and the influence mechanism of cryogenic treatment were analyzed. [ABSTRACT FROM AUTHOR]

Eyelid tarsus is a fibrocartilagenous extracellular matrix around meibomian glands providing structural support to eyelids and play important roles in the integrity of the ocular surface. There are no previous studies investigating the relationship between micro-structure and function of eyelid tarsus. To investigate the structure of extracellular matrix and the biomechanical properties of tarsus, rabbit tarsus were stained with hematoxylin and eosin (H&E), MASSON and Verhoeff's Van Gieson (EVG), distribution of collagen and elastin fibers in tarsus extracellular matrix were analyzed with scanning electron microscopy. Tarsus strips were collected and went through uniaxial tensile test with an Instron Universal Testing Machine. Data from 15 tarsus samples were included in the study. The initial tensile modulus was 2.554 ± 1.453 Mpa, and the final tensile modulus was 23.554 ± 3.657 Mpa, with an extensibility of 35.47 ± 7.46%. Collagen fibers formed peripheral layers of lamellae around meibomian glands, while the elastin fibres were organized in a parallel arrangement in horizontal and sagittal section, and in a crossed arrangement around meibomian glands. After tensile test, elastin fibres were stretched and arranged perpendicular to the direction of the collagen fibril lamellae. The findings of this study suggest that the extracellular matrix structure formed by collagen-elastin network contributes to a nonlinear mechanical characteristic of eyelid tarsus. [ABSTRACT FROM AUTHOR]

In this study, CoCrFeNiAl x (x = 0.1, 0.5, 1) high-entropy alloys (HEAs) are prepared using vacuum arc melting. In order to improve the surface properties of CoCrFeNiAl x HEAs, their microstructure is manipulated by laser surface remelting (LSM). The microstructure, the mechanical properties, and the corrosion resistance of the HEAs before and after LSM are studied systematically. The microstructural analysis reveals that the LSM-samples contained either a single FCC phase (CoCrFeNiAl 0.1 and CoCrFeNiAl 0.5) or a mixture of BCC + B2 phases (CoCrFeNiAl 1) with refined grains. Moreover, BCC precipitates and a spherical nano-dispersed phase (B2) are detected in the surface layer of CoCrFeNiAl 0.5 and CoCrFeNiAl 1 , respectively. The mechanical properties of CoCrFeNiAl x alloys are found to be significantly enhanced after LSM, which is mainly ascribed to the generation of the BCC phase, dislocation reinforcement and grain-strengthening as well as precipitation hardening. The electrochemical measurements confirm that all samples (after LSM) have a positive potential and a lower current density in 3.5 wt% NaCl solution compared to the untreated sample. The results indicate that LSM can help homogenize the structure and improve the properties of CoCrFeNiAl x HEAs. [Display omitted] • LSM treatment was conducted on the surface of as-cast CoCrFeNiAlx (x = 0.1,0.5,1) HEAs and the grains of each component were refined obviously. • A 365.2–1200 μm thick remelted layer was formed. • After LSM, abundant dislocation structures appeared on the surface, and spherical nano dispersed B2 phase was found in Al 1. • Surface microhardness, wear and corrosion resistance were improved evidently. [ABSTRACT FROM AUTHOR]

[Display omitted] • The deep cryogenic treatment was first applied to TC4/4J36 diffusion welding joint. • The effects of soaking time and cycles on mechanical properties of joint were studied. • The deep cryogenic treatment improves the quality of dissimilar joint between titanium alloy and steel. • The influence mechanism of deep cryogenic treatment on joint was studied. The diffusion welded joints of 4J36/TC4 with Ni/Cu/V metal interlayer were subjected to deep cryogenic treatment. The results showed that the extension of soaking time could improve the mechanical properties of the joint. The sample soaked for 8 h had the best performance, and it possessed ultimate tensile strength of 357.9 MPa and elongation of 24.9%. All samples failed at Cu/Ni interface with a ductile fracture manner, indicating that the joint still had good performance at low temperature. [ABSTRACT FROM AUTHOR]

• The V/Cu/Ni interlayer was first applied to weld TC4 titanium alloy and 4J36 invar alloy. • The use of V/Cu/Ni interlayer produces solid solutions at all interfaces. • The use of V/Cu/Ni interlayer improves the quality of dissimilar joint between titanium alloy and steel. • The formation mechanism of 4J36/Ni/Cu/V/TC4 bonded joints was studied. Diffusion bonding of 4J36 invar alloy and TC4 titanium alloy was carried out by inserting Ni/Cu/V multi-layer metal interlayer. The results showed that temperature had a significant effect on microstructure and mechanical properties of welded joints. At 890 °C, the joint tensile strength reached maximum value of 249.3 MPa. Fe-Ni solid solution ((Fe,Ni)ss), Cu-Ni solid solution ((Cu,Ni)ss), V-Cu solid solution ((V,Cu)ss) and Ti-V solid solution ((Ti,V)ss) were produced at interfaces of 4J36/Ni, Ni/Cu, Cu/V and V/TC4, respectively, and fracture surfaces of all joints showed dimples of different sizes, which showed that the application of Ni/Cu/V interlayer was an effective method. [ABSTRACT FROM AUTHOR]

Laser remelting (LR) treatment was used to regulate the microstructure of AlCoCrFeNiTa x high-entropy alloys prepared by vacuum arc melting, and the microstructure and properties of the alloys before and after LR treatment were analyzed. The original AlCoCrFeNiTa x alloys have typical dendritic morphology and the addition of Ta element promoted the formation of a Laves phase, gradually changing the alloys from two phase (BCC + B2) to three phase (BCC + B2 + Laves phase). After LR treatment, the grains were significantly refined, elemental segregation was alleviated, and a dense remelting layer with a thickness of 1200–1600 µm was formed on the surface of the alloy. In addition, the hardness and wear resistance of the alloys were improved with increasing Ta content and LR treatment, mainly caused by the combined effects of solution strengthening, second phase strengthening and fine grain strengthening. At the same time, the corrosion resistance of the alloys before and after LR treatment in 3.5 wt% NaCl solution is significantly improved by a stable Ta 2 O 5 and TaO 2 passivation films and the formation of a dense uniform remelting layer. • Refractory element was added and LR treatment was conducted on the surface of AlCoCrFeNiTax high entropy alloy. • After LR treatment, elemental segregation on the alloy surface is alleviated and the alloy grains are refined. • A remelted layer of about 1200–1600 µm thickness was formed on the alloy surface after LR treatment. • The hardness and wear resistance of the alloys were improved with increasing Ta content and LR treatment. • The corrosion resistance of the alloys in 3.5 wt% NaCl solution is improved by passivation film and remelted layer. [ABSTRACT FROM AUTHOR]

In order to improve the properties of AlCoCrFeNiNb x (x = 0, 0.1, and 0.5) high-entropy alloys (HEAs), the microstructure of the AlCoCrFeNiNb x is regulated by laser remelting (LR). By testing the microstructure and properties of alloys before and after LR treatment，the results indicate that the original AlCoCrFeNiNb x alloys have typical dendritic morphology, and the addition of the Nb element promoted the formation of Laves phase. The grains were significantly refined after LR treatment, and the dense remelting layers with thicknesses ranging from 1200 μm to 1650 μm were formed on the surface of the alloys. In addition, the hardness and wear resistance of the alloys were improved with the increase of Nb content and LR treatment due to the combined effect of fine grain strengthening, solid solution strengthening, and the second phase strengthening. At the same time, the corrosion resistance of the alloys before and after LR treatment in 3.5 wt% NaCl solution was significantly improved by the stable Nb 2 O 5 passivation film for Nb 0 and Nb 1 alloys. • LR treatment was conducted on the surface of as-cast AlCoCrFeNiNb x (x = 0.1,0.5 and 1) high entropy alloys. • AlCoCrFeNiNb x alloys have typical dendritic morphology, and the addition of the Nb element promoted the formation of Laves phase. • The grains were significantly refined after LR treatment, and the dense remelting layers with thicknesses ranging from 1200 μm to 1650 μm were formed on the surface of the alloys. • The hardness and wear resistance of the alloys were improved with the increase of Nb content and LR treatment due to the combined effect of fine grain strengthening, solid solution strengthening, and the second phase strengthening. • The corrosion resistance of the alloys before and after LR treatment in 3.5 wt% NaCl solution was significantly improved by the stable Nb 2 O 5 passivation film for Nb 0 and Nb 1 alloys. [ABSTRACT FROM AUTHOR]