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Aiming at the difficulty of accurately calibrating the sample position in the terahertz (THz) imaging process, especially in the defect imaging detection and the precise characterization of the edge profile, a flexible and highly sensitive 3D terahertz displacement sensor with a resolution of up to 1 μm was proposed by the artificial electromagnetic metamaterials. The high resolution of the flexible sensor can be attributed to the used artificial electromagnetic metamaterials with the enhancing sensitivity of THz sensors as well as the flexible substrate with the high fitting to the target. Unlike the laser displacement sensor with a complex and large volume of the generating device, the proposed flexible sensor with a simple structural design is composed of only a fixed layer and a displacement indicating layer. The fixed layer is composed of the Mylar flexible substrate layer and the metal split resonator ring on it, and the displacement indicating layer is composed of the Mylar flexible substrate layer and the metal indicator lines on it. By using this unique double-layer structure, high-sensitivity measurement of displacement can be achieved by measuring the moving amount of the metal indicator line corresponding to the valley change in the THz transmission of the displacement sensor. The results demonstrate that the sensitivity of the displacement sensor can reach 145 GHz/μm, the quality factor Q can reach 194.67, and the quality factor figure of merit can reach 6.25 μm−1. Compared with the mature commercial displacement sensors and laser displacement sensors, the proposed sensor can have the characteristics of compact structure, simple preparation process, high-sensitivity, and flexibility, which can offer certain advantages for the realization of high-precision, miniaturization, and distributed sensing systems in the future.

Wheat bran, which contains a large amount of cellulose, is used as a raw material to produce soy sauce, but it is hard to degrade during fermentation. Steam explosion (SE) is efficient in hydrolyzing the cellulose for enhancing enzymatic digestion and solvent accessibility. In this study, we applied a SE at a sufficiently high pressure to damage the integrity of the wheat bran structure and modify it to assume a layered form. We found that cellulose, hemicellulose, and lignin structures were collapsed by SE pretreatment, which was indicated by their changes in Fourier transform infrared spectroscopy (FTIR). The amounts of cellulose, hemicellulose, and lignin decreased by 5.8%, 21.4%, and 43.4%, respectively, under 1.5 MPa, resulting in the significant reduction of sugar and amino acid nitrogen. The co-reaction of nonenzymatic browning after SE pretreatment resulted in an intense increase in flavor (overall feeling), as determined by electronic nose analysis and sensory evaluation. In conclusion, SE pretreatment under 1.0 MPa was proven to be the most optimal state for the production of aroma compounds (volatile compounds), which are essential for soy sauce production.

The new technique of interspecific hybridization was created in Gossypium which could remarkably overcome abortion of interspecific hybridization and hybrid sterility of F(1). A large number of germplasm resources were obtained from seventy cross combinations among the cultivated species and between the cultivated and the 14 wild species, respectively. 8 varieties have been developed, of which 4 were from the cross combination of G. hirsutum x G. arboretum and the other are the first breed from the hybrids between G. hirsutum and 4 wild species, respectively. Of them Shiyuan 321 (jimian 24) is a new variety which had the highest increase in the national Yellow River Valley Regional test, with planting area added up to 933333 ha in the recent three years. The breeding system of interspecific hybridization was established.