In this work, polylactic acid (PLA) biocomposites reinforced with short coir fibers were fabricated using a corotating twin-screw extruder and injection molding machine. Short coir fibers were treated by mixed solution including hydrogen peroxide and sodium hydroxide to improve the adhesion between fibers and PLA matrix. The effects of treated coir fiber content (1, 3, 5, and 7 wt%) on tensile, impact, thermal properties, and surface morphology of PLA biocomposites were investigated. The best impact strength results were obtained for 3 wt% PLA/treated coir fiber biocomposites, where the impact strength was increased by approximately 28% compared to the neat PLA. The tensile modulus of PLA biocomposites was increased by increasing the treated coir fiber content. These results were confirmed by morphological structure analysis. Differential scanning calorimetry (DSC) results demonstrated a minor effect of the treated coir fiber on thermal behavior of PLA resin. Thermogravimetry analysis (TGA) demonstrated that the thermal stability of the PLA/treated coir fiber biocomposites was reduced by the incorporation of treated coir fiber.

Alkali-treated coir fibers were modified by silane coupling agent in a microwave oven. The use of microwave-assisted chemical treatments efficiently promoted the esterification reaction to improve the interfacial adhesion between the coir fibers and PLA matrix. Effects of the treated coir fiber content (1 wt.% to 7 wt.%) on the surface morphology and tensile, impact, and thermal properties of PLA/coir fiber biocomposites (AKWCF/PLAs) were evaluated. At a coir fiber content of 1%, the AKWCF/PLAs showed a remarkable increase of 28% in the percentage impact strength, while the tensile strength and breaking strength decreased with increasing coir fibre content. The thermal stability of the AKWCF/PLAs worsened and the degree of crystallinity increased with increasing fiber content. The decreased cold crystallization temperatures of AKWCF/PLAs further confirmed the role of coir fibers treated with the new combined method as an effective nucleating agent.

Because of their high nutritional value, the demand for scallops is increasing year by year. In the process of improving people’s living standards, the ready-to-eat characteristics and dry sales characteristics of this product make its shelling process particularly important in the production process. However, the mechanism of ultra-high pressure shelling has not yet been clarified. Therefore, in-depth study of the structural change of the scallop connection interface is of vital importance to explore the mechanism of ultra-high pressure shelling and the development of intelligent equipment from the mechanical point of view. The obturator muscle fibers and the inner surface materials of the shell at the obturator muscle scar of the scallop at 100, 200 and 300 MPa were obtained for Raman spectrum, Fourier-transform infrared spectrum and scanning electron microscopy analysis. The results showed that under the pressure of 200 MPa, the degree of protein denaturation of scallop adductor muscle increased, the elasticity disappeared, and the fiber was stretched; The deformation of the organic plasma membrane connected by the inorganic–organic interface weakens the binding force of the interface material and increases the possibility of the composite interface failure. To sum up, ultra-high pressure can effectively weaken the interface adhesion of scallop organic-inorganic composite materials, and is one of the effective ways of shelling. The research results can provide a basis for the in-depth analysis of ultra-high pressure mechanisms and the development of intelligent equipment, and provide technical support for the realization of ultra-high-pressure industrial production.

Modeling software was used to improve the efficiency of existing immersion freezing equipment. The concept of adding a rotating hopper device was proposed to make pork rotate with the rotating hopper in a flowing refrigerant carrier to achieve the effect of shortening the freezing time. In order to make up for the shortcomings of time-consuming processes and the limited information obtained from the measurement of the central temperature of pork, this paper establishes a mathematical model of the pre-freezing process using computational fluid dynamics (CFD) software to simulate the three-dimensional unsteady state of the pork. The simulation results show that when the rotating hopper is stationary, the refrigerant circulation flow shortens the freezing speed by 490 s compared to the freezing speed in the stationary state of the refrigerant carrier, and the freezing time efficiency is improved by 9.5%. When the refrigerant carrier flow rate v = 0 m/s and when the hopper speed r = 2 rad/s, the central temperature of pork drops rapidly from 26 °C to −15 °C in 0~1250 s, the decline leveled off at 1250–2310 s, and finally dropped to −18 °C, requiring a total of 5410 s. The freezing time of the immersion and freezing equipment was reduced by 2830 s after the addition of the rotating device, improving efficiency by nearly 55%. When the rotation speed r is increased from 2 rad/s to 4 rad/s, the freezing time is shortened by 1290 s and the freezing efficiency is increased by nearly 53%. The addition of the rotating device will make the pork freezing effect more uniform.

Shell is a typical biomineralized inorganic–organic composite material. The essence of scallop deshelling is caused by the fracture failure at the interface of the organic and inorganic–organic matter composites. The constitutive equations were solved so that the stress distributions of the adductor in the radial, circumferential, and axial directions were obtained as σ_r = σ_θ = P, σ_z = 2(2 − ν)P/(2ν − 1), and the shear stress was τ_zr = 0. Using the method of finite element simulation analysis, the stress distribution laws at different interface states were obtained. The experimental results show that when the amplitude is constant, the undulation period is smaller than the diameter of the adductor or the angle between the bus of the adductor, and the reference horizontal plane gradually decreases, so the interface is more likely to yield. After the analysis, the maximum stress for the yielding of the scallop interface was about 247 MPa, and the whole deshelling process was gradually spread from the outer edge of the interface to the center. The study analyzed the scallop organic–inorganic material interface from the perspective of mechanics, and the mechanical model and simulation analysis results were consistent with the parameter optimization results, which can provide some theoretical basis for the composite material interface failure and in-depth research.