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Molecularly imprinted polymer (MIP) beads imprinted with vitamin E (VE) were synthesized via a two-step swelling polymerization method, using methacrylic acid (MAA) and other functional monomers together with polystyrene (PS) microspheres as the substrate. In initial trials, different functional monomers were assessed, along with a variety of solvents and imprinting ratios. The MIPMAA sample exhibited the highest performance and was characterized and also assessed with regard to VE adsorption under various experimental conditions. This material exhibited reasonably good sphericity, porosity and stability, along with an excellent adsorption capacity of 46 mg/g. This was much higher than the value for the corresponding non-imprinted polymer made with the same monomer, and 20% higher than that for an acrylamide-based MIP synthesized using a precipitation polymerization method. The core-shell structured MIPMAA also demonstrated fast adsorption kinetics, a low pressure drop and good reusability in fixed bed experiments. The VE adsorption equilibrium, selectivity, kinetics, thermodynamics and regeneration capacity of this material were also examined and are reported herein.

Aiming at the fatigue fracture phenomenon in the T-welded structure, the ANSYS finite element method is used to calculate the stress intensity factor of the crack, and the law of its change under different crack shape ratios is analyzed, and the law of crack propagation is analyzed. The calculation results show that keeping the crack depth constant, as the crack shape ratio increases, the overall stress intensity factor at the crack decreases, and the maximum stress intensity factor at the crack gradually transitions from the crack front edge to the crack tip. This indicates that with the increase of the crack shape ratio, the ability of the crack to resist the growth increases, and the crack gradually transitions from the original crack front edge to the crack tip.

In the chemical production process, chemical equipment and parameters need to be monitored in real time or warning of exceeding standards. Due to its own advantages, optical fiber sensors are used for chemical parameter detection and chemical equipment condition monitoring with high safety and reliability. It introduces in detail the monitoring of long-period fiber grating (LPG) sensors in pH, Humidity, CO2, H2S, CL- and other chemical parameters, and the application of fiber Bragg grating (FBG) sensors in temperature and strain monitoring. Finally, the application of fiber grating sensor in chemical parameter detection and chemical equipment condition monitoring is summarized and prospected.

Molecularly imprinted polymers (MIPs) were prepared by the precipitation polymerization process, with vitamin E as the template molecule, ethylene glycol dimethacrylate as the cross-linker, and three different functional monomers, respectively. Adsorption experiments were conducted to investigate the performance of each MIP and compared to the nonimprinted polymers (NIPs). It was found that MIPs are superior to NIPs in general, with acrylamide-based MIP showing the best adsorption capacity of 38.8 mg·g–1 and an imprinting factor of 2.6. The optimal imprinting ratio and cross-linking ratio to be 1:5 and 5:1, respectively. The Freundlich equation was found superior to Langmuir to describe the adsorption isotherm data on the MIP/NIP. The adsorption of vitamin E on the MIP was found to be a heterogeneous process and consists of two mechanisms, which were confirmed by the analysis of the thermodynamic properties of the adsorption process.

Wild (Bombyx mandarina) and domestic silkworms (B. mori) are good models for investigating insect domestication, as 5000 years of artificial breeding and selection have resulted in significant differences between B. mandarina and B. mori. In this study, we improved the genome assemblies to the chromosome level and updated the protein-coding gene annotations for B. mandarina. Based on this updated genome, we identified 68 cytochrome P450 genes in B. mandarina. The cytochrome P450 repository in B. mandarina is smaller than in B. mori. Certain currently unknown key genes, rather than gene number, are critical for insecticide resistance in B. mandarina, which shows greater resistance to insecticides than B. mori. Based on the physical maps of B. mandarina, we located 66 cytochrome P450s on 18 different chromosomes, and 27 of the cytochrome P450 genes were concentrated into seven clusters. KEGG enrichment analysis of the P450 genes revealed the involvement of cytochrome P450 genes in hormone biosynthesis. Analyses of the silk gland transcriptome identified candidate cytochrome P450 genes (CYP306A) involved in ecdysteroidogenesis and insecticide metabolism in B. mandarina.

In order to obtain more accurate information in the analysis of visual information, this paper combines spatial relationships and uses two image and video processing tools, PS and AE, to establish “scale model”, “cross-ratio theorem model”, “similarity model of viewing angle distance”, “velocity measurement model of longitudinal plane translation”, and designed “viewing angle solution algorithm”. The results show: through the above models and algorithms, mathematical tools such as MATLAB and Python3 can be used to efficiently, accurately and quickly calculate the height, floor area and road length of the building in the 3D video information, and obtain the horizontal view of the drone lens, longitudinal viewing angle and its flying height and speed.

DNA methylation is an important epigenetic modification and has been shown to be involved in the response to abiotic stress. However, there are few studies on DNA methylation in insect response to environmental signals. In this study, we conducted a comprehensive comparative analysis of DNA methylation profiles between two silkworm strains with significantly different resistance to heat and humidity by whole-genome bisulfite sequencing (WGBS). We identified, in total, 2934 differentially methylated regions (DMRs) between RT_48h (resistant strain with high-temperature/humidity treatment for 48 h) and ST_48h (sensitive strain with high-temperature/humidity treatment for 48 h) under cytosine context (CG), which corresponded to 1230 DMR-related genes (DMGs), and the DMRs were primarily located in the gene body (exon and intron) region. Gene ontology (GO) and KEGG analysis showed that these DMGs were most significantly enriched in binding, cellular metabolic process, and RNA transport pathways. Moreover, 10 DMGs have been revealed to be involved in the heat-humidity stress response in the silkworm. The results of this study indicated that DNA methylation plays crucial roles in silkworm response to environmental stressors and provides important clues to identify key resistance genes in silkworm under high-temperature/humidity stress response.

The stress analysis and optimization of carbon fiber composite laminates were carried out by using the finite element optimization design software Altair Optistruct. When the laminate bears the axial load, the mechanical properties of the laminate are studied. At the same time, the scheme design, preliminary design and detailed design are carried out, and the optimal design of the carbon fiber composite laminate is carried out. The design variables are the thickness of the laminates and the sequence of the laminates, and the constraints are volume fraction, maximum or minimum principal strain of the single layer. The objective optimization of the minimum compliance and the minimum mass of the laminated plate are carried out. The simulated strength of the optimized carbon fiber composite laminates was checked. The results show that after three stages of optimization, the compliance and the mass of carbon fiber composite laminates are reduced by 11.8% and 16%, respectively, the results of strength check and optimization are safe, and the optimization design is reasonable and reliable.