This study aims to explore the corrosion behavior of bitter almond oil (BAO) during processing. Hydrocyanic acid (HCN) and benzoic acid in oil are speculated as the main components that corrode the screw oil expeller. Immersion and simulation corrosion tests are carried out to verify this hypothesis. Immersion test results show that crude BAO (CBAO) containing 5.07 ± 0.06 mg kg −1 benzoic acid and 4.25 ± 0.04 mg kg −1 HCN exhibits corrosive effects on steel. Simulation corrosion test results indicate that the addition of CN − or benzoic acid has significant effect on the corrosion of steel. Specifically, at ≥1 × 10 4 mg kg −1 benzoic acid concentration or ≥5 mg kg −1 CN − concentration, the mass of steel blocks in oil decreases and the contents of Fe, Zn, Al, and Mg ions in oil increase significantly. Therefore, HCN in CBAO is the main cause of screw oil expeller corrosion in BAO processing and benzoic acid is the secondary cause. Practical Applications : The corrosion behavior of CBAO not only damages the integrity of the screw oil expeller but also increases the dissolution of toxic metals from the components into oil. The study of corrosion has practical value in taking effective measures, such as detoxification before pressing and addition of natural inhibitors, to reduce corrosion and ensure the quality of CBAO. Corrosion study provides the basis for the selection of steel materials of screw oil expeller.
To enhance the performance of stainless steel materials in low temperature environments, a bioinspired hydrophobic surface with synergistic delayed icing/frosting properties was developed, mimicking the microstructural and chemical characteristics of natural surfaces exhibiting exceptional hydrophobicity and ice resistance. Advanced laser processing technology fabricated a precisely engineered polygonal microarray structure on stainless steel substrates. Subsequently, a nanocomposite colloidal was formulated, consisting of a TiO 2 polyurethane hybrid bonding colloid and CB-SiO 2 hybrid adhesive solution. These functional materials uniformly deposited onto the structured surface via spray coating, forming a robust, bond stabilized super liquid repellent coating with outstanding delayed icing/frosting performance. The experimental results demonstrate that the L-CB@SiO 2 SHCS exhibits superhydrophobic properties, with a static contact angle reaching up to 154.2° and a sliding angle less than 5°. Under cryogenic conditions (−10 °C and −15 °C), the surface significantly delayed ice nucleation by 6824 s and 1715 s, respectively. Moreover, the coating maintained excellent icephobicity, with water droplets completely shedding after 30 impact cycles without ice residue. Even after prolonged exposure 60 min, only a minimal frost layer formed. To elucidate the mechanistic basis of the composite colloidal film's superior anti-icing performance, comprehensive material characterization performed using XRD, FTIR and XPS. Furthermore, the coating durability rigorously assessed through sandpaper rubbing, ethanol hydrolysis, grit falling, and icing-melting cycle tests. The development of such advanced anti-icing stainless steel surfaces holds significant practical implications, as it can substantially reduce de-icing maintenance costs while extending the operational lifespan of cryogenic equipment.
Tianyu Cui,Qingsuo Liu,Xin Zhang,Dawei Zhang,Jinman Li
The formation of nanocrystalline structures in bulk metal materials is of great significance for both investigating the structural features of nanocrystalline materials and enhancing the value of bulk metal materials in engineering applications. Herein, we report a nanocrystalline structure formed by lattice transformation in a three-dimensional bulk metal material. We characterized its phase composition, three-dimensional features, and boundary structure. This nanocrystalline structure had microscale length and height and nanoscale width, which gave it a “nanoplate” structure in three-dimensional space. We observed edge dislocations in the interior of the nanocrystalline structure. A unique transitional boundary that contributed to maintaining its nanoscale size was found at the border between the parent phase and the nanocrystalline structure.Keywords:nanocrystalline structure;grain boundaries;microstructure;three-dimensional features
危险品化学品经营许可证（带存储）