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The activity of Ni3Sn powder after oxidation-reduction treatment was investigated for producing hydrogen from methanol under different conditions. The treated Ni3Sn powder, especially that the Ni3Sn oxidized at higher temperature showed a much higher activity than non-treated Ni3Sn; compared to Ni3Sn oxidized at 1073 K, Ni3Sn oxidized at 1373 K showed 10 times higher H2 and CO generation rates, but similar low CO2 and CH4 generation rates. The activity of treated Ni3Sn significantly increased with increasing oxidation temperature and decreasing reduction temperature. The activity improvement of treated Ni3Sn powder was attributed to the formation of fine nanostructured Ni/SnO2 particles, which were supposed to be the cause of the improved activity of Ni3Sn.

This study aimed to develop a bilayer active film by using polyvinyl alcohol (PVA)/ethylene-vinyl acetate copolymer (EVA) and antioxidant essential oils. The effect of the bilayer active film on the quality and shelf-life of mutton was investigated. PVA laminated material was considered to improve the barrier capacity, while essential oils incorporated into EVA laminated material conferred antioxidant and antimicrobial activity. The effect of the addition of essential oils on the film by mechanical properties, oxygen permeability, scanning electron microscopy (SEM) image, Fourier transform infrared spectroscopy (FTIR), Differential Scanning Calorimetry (DSC) was investigated. Releasing of active compound into mutton and antioxidant activity was investigated to evaluate the films. The antibacterial effects of bilayer active films were subsequently evaluated based on the antibacterial properties of active film and Total viable counts (TVC) of mutton. Microbial community structure in the mutton of different packaging was analyzed by Illumina MiSeq sequencing. Based on total volatile basic nitrogen (TVB-N), the shelf life of mutton was tested. The results showed that the active compound improved flexibility and ductility of active PVA/EVA films. The results also showed a high release of OEO (21.99 mg/kg) and TTO (17.96 mg/kg) as well as high antioxidant and antimicrobial efficiency of PVA/EVA films with essential oils. High-throughput sequencing has shown that the addition of OEO and TTO can reduce the type of dominant bacteria, reducing Acinetobacter by 15.8% and 15.55%, respectively. The release test of active compounds into the mutton showed that the higher contents of the active compounds released, the more microbial proliferation limited, thereby it effectively retarded the increase of TVB-N, which extended the shelf life of mutton by 5–6 days.

Four micro-holes were made using a micro-EDM on the rake and flank face of cemented carbide (WC/TiC/Co) tools. Molybdenum disulfide (MoS2) solid lubricants were embedded into the four micro-holes to form self-lubricating tools (SLT-1 and SLT-2). Dry machining tests on hardened steel were carried out with an SLT-1 self-lubricating tool with four micro-holes embedded with MoS2 solid lubricants in the rake face, an SLT-2 tool with four micro-holes embedded with MoS2 in the flank face, an SLT-3 tool with four micro-holes embedded without MoS2 in the rake face, an SLT-4 tool with four micro-holes embedded without MoS2 in the flank face and a conventional tool SLT-5. The cutting forces, tool wear, and average friction coefficient at the tool-chip interface were measured and compared. Finite Element Analysis (FEA) was used to analyze the effect of micro-holes on the mechanical properties of cutting tools. It was shown that the cutting performance of SLT-1 and SLT-2 self-lubricated tools were greatly improved compared with that of SLT-3, SLT-4, and SLT-5 tools. The SLT-1 self-lubricating tool possessed the lowest friction coefficient, while the SLT-2 self-lubricating tool resulted in a lower flank wear. It is indicated that cemented carbides embedded with MoS2 solid lubricants in the wear face is an effective way to reduce the rake and flank wear of conventional tools.

Micro-holes were made using micro-EDM on the rake and flank face of the cemented carbide (WC/Co) tools. Molybdenum disulfide (MoS2) solid lubricants were filled into the micro-holes to form self-lubricated tools (ML-1 and -2). Dry cutting tests on hardened steel were carried out with these self-lubricated tools and conventional tools (ML-3). The cutting forces, the tool wear, and the friction coefficient between the tool–chip interface were measured. It was shown that the cutting forces with ML-1 and -2 self-lubricated tools were greatly reduced compared with that of ML-3 conventional tool, the ML-1 self-lubricated tool with one micro-hole in its rake face possessed the lower friction coefficient at the tool–chip interface; while the ML-2 self-lubricated tool with one micro-hole in its flank face revealed more flank wear resistance. The mechanism responsible was explained as the formation of a self-lubricating film between the sliding couple, and the composition of this lubricating film was found to be MoS2 solid lubricant, which was released from the micro-hole and smeared on the rake or flank face, and can be acted as lubricating additive during dry cutting processes.

The element diffusion from the Ti–6Al–4V titanium alloy to WC/Co carbide tools (vice versa) at temperatures up to 800 °C was examined. The morphology of the diffusion couples was detected by SEM. Dry turning tests on Ti–6Al–4V alloy were carried out with WC/Co carbide tools. Results showed that W and Co elements did not greatly penetrate into the Ti–6Al–4V alloy at 400 °C; while at 600 °C, W and Co diffused a long way into the Ti–6Al–4V alloy, and the penetrating depth reached 20 μm at 800 °C. The hardness near the interface of the diffusion couples is lower than those far away from the interface owing to element diffusions. The element diffusion from the Ti–6Al–4V to the WC/Co carbide tools (vice versa) through the tool–chip interface in machining processes leads to a composition change of the tool substrate, which may accelerate the tool wear.

MoS2/Zr composite coatings were deposited on the surface of YT15-cemented carbide. Microstructural and fundamental properties of these coatings were examined. Dry cutting and sliding wear tests on hardened steel were carried out with these coated tools. Results showed that PVD MoS2/Zr composite coatings onto the cemented carbide substrate show higher hardness and better adhesion with the substrate in comparison with the pure MoS2 coatings, and exhibit decreased friction coefficient to that of the uncoated carbide in sliding wear tests. Cutting speeds were found to have a profound effect on the wear behaviors of MoS2/Zr-coated tools. In case of low-speed cutting, the MoS2/Zr-coated tools showed much better cutting performance compared to the uncoated tools, the MoS2/Zr coatings on the rake face can be acted as lubricating additives between the tool–chip sliding couple during cutting processes, and contribute to the decrease of the tool wear; while in high-speed cutting processes, there are quite a number of cracks on the coating owing to the elevated cutting temperature, which may initiate the loss of the coating from the tool face, and lead to the increase of the tool wear.

Medium-frequency magnetron sputtered PVD ZrN coatings were deposited on YG6 (WC + 6 wt% Co) cemented carbide. Microstructural and fundamental properties of the ZrN coatings were examined. Sliding wear tests against hardened steel using the ring-block method and dry machining tests on hardened steel were carried out with these coated materials. The friction coefficient and wear rates were measured. The wear surface features of the coatings were examined by scanning electron microscopy. Results showed that the PVD ZrN coatings onto the cemented carbide substrate show high hardness and good adhesion with the substrate. The friction coefficient of the sliding couples increased with the applied load and the sliding distance. Failures of the ZrN coating occur down to the carbide substrate under high load conditions or with long sliding distance in sliding wear tests, and are accompanied by the extensive abrasive wear on the substrate owing to the wear debris. The ZrN coated tools showed much better cutting performance compared to the YG6 uncoated carbide, which is connected with their large hardness increase, and good abrasive wear resistance. Abrasive wear was found to be the predominant flank wear mechanism for the ZrN coated tools. While the mechanisms responsible for the rake wear were determined to be adhesion.

Mesoporous Sn 0.9 Ti 0.1 O 2 was prepared by controlled hydrolysis of chlorides and subsequent removal of templates by calcination in air. X-ray diffraction, SEM and nitrogen adsorption–desorption results showed that the mesoporous Sn 0.9 Ti 0.1 O 2 consisted of nanocrystals with the average size of 10 nm. The special surface area and average pore size were 70 m 2 /g and 9 nm, respectively, for the mesoporous Sn 0.9 Ti 0.1 O 2 . The film sensors based on the Sn 0.9 Ti 0.1 O 2 exhibited abnormal photoelectrical properties. The photocurrent of the sensor decreased with increasing UV light intensity in air, but increased with increasing UV light intensity in vacuum. The gas response of the Sn 0.9 Ti 0.1 O 2 sensor to 1000 ppm ethanol was about 8.2 under UV light at room temperature. The conductance mechanism and gas sensing mechanism of the mesoporous nanostructure oxides was discussed.