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In this work, a structure of assembled porous graphene multilayer frameworks was demonstrated to endow the resultant sensing devices with batch uniformity, good response, sensitivity, and selectivity.

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In order to improve the performance of surface plasmon resonance (SPR) biosensor, the structure based on two-dimensional (2D) of graphene and transition metal dichalcogenides (TMDCs) are proposed to greatly enhance the Goos-Hänchen (GH) shift. It is theoretically proved that GH shift can be significantly enhanced in SPR structure coated with gold (Au)-indium tin oxide (ITO)-TMDCs-graphene heterostructure. In order to realize high GH shifts, the number of TMDCs and graphene layer are optimized. The highest GH shift (−801.7 λ) is obtained by Au-ITO-MoSe2-graphene hybrid structure with MoSe2 monolayer and graphene bilayer, respectively. By analyzing the GH variation, the index sensitivity of such configuration can reach as high as 8.02 × 105 λ/RIU, which is 293.24 times of the Au-ITO structure and 177.43 times of the Au-ITO-graphene structure. The proposed SPR biosensor can be widely used in the precision metrology and optical sensing.

The fatigue crack growth behavior in 20CrMnTi lath martensitic steel with a hierarchical structure was investigated at room temperature. The microstructure was quantitatively characterized by optical microscopy, scanning electron microscopy, electron backscattering diffraction, and transmission electron microscopy. Crack growth tests were performed at a stress ratio of 0.1 under the control of a stress intensity factor range using compact tension specimens. The results show that the lath martensite with medium grain size quenched in ice salt water possessed the highest fatigue crack propagation resistance, which was attributed to the relatively high intrinsic propagation resistance and extrinsic propagation resistance. Meanwhile, the results indicate that the intrinsic propagation resistance increased with the grain size, while the extrinsic propagation resistance showed an inverse tendency. In addition, the effect of substructure on the fatigue propagation properties is discussed. The deflection angle of block interfaces in the crack growth path indicated the block unit had a significant effect on the fatigue crack propagation behavior of lath martensitic steel. Based on the Taylor model, the block size (db) was considered to be the effective grain size for controlling the crack growth threshold value (∆Kth).