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Different steel welding joints are widely used in special equipment and often bear the role of high temperature and high pressure, and corrosive media. Because dissimilar steel welded joints are prone to residual stress and defects during welding, cracks may occur during use. Due to the tissue structure of heterogeneous steel and austenite, ultrasonic detection and surface detection methods are poor. This paper puts forward the ray detection method, including artificial defects, using the ray detection method. Detection results show that the heterogeneous steel welding joint internal defects and that the ray detection method has a good detection effect.

Fiber reinforced plastics are used in pressure vessel manufacturing because of their high strength and corrosion resistance.Defects may occur in the manufacture and use of the pressure vessel. To ensure safe operation of the pressure vessel, it is necessary to conduct periodic safety assessment of the pressure vessel put into operation. It is difficult to evaluate the safety status of fiber-reinforced plastic pressure vessels by conventional nondestructive testing.Acoustic emission detection technology is a dynamic detection method, which has obvious advantages for the performance and fracture process of fiber reinforced plastic materials. ASME section V or ASTM section on acoustic emission detection of FRP pressure vessels, in which the localization of defects is mainly based on acoustic emission instruments. Due to the anisotropy of FRP material, the instrument can only give the area of the defect, and then use other non-destructive testing methods supplementary detection, so the author proposes a regional positioning method, which can locate defects more accurately. In this paper, acoustic emission detection method and lead breaking method were used to simulate the deficiency, and acoustic velocity attenuation and variation of fiber reinforced plastics were studied, and confirmative tests were carried out to obtain the positioning accuracy of the deficiency in different areas.In order to achieve the acoustic emission (AE) response behavior of stretching damage of glass fiber composites with fiber pre-broken and weak bonding, stretching tests and real-time AE monitoring of glass fiber composites were conducted.Experimental results showed that damage model such as matrix cracking and fiber fracture and bending could be occurred in the process of damage and failure. The composition and content of signal frequency of AE is also different because of difference of preset defect.

Regular inspection is important to verify the integrity of in-service pipeline in the petrochemical industry. Early detection of flaws is therefore essential to ensure the continued safe operation of pipeline. In generally, Conventional ultrasonic for thin-walled small-diameter pipes has limitations due to regulation requirements, efficiencies, lack of permanent results and repeatability. In many cases, the preferred method of inspection is radiographic testing, however there are many obvious shortcomings for radiographic detection. The aim of this work was to propose appropriate phased array ultrasonic scan plans that were able to achieve the following: reduce the inspection times, improve defect detectability and sizing, and reduce human intervention, which will reduce workforce radiation uptake. Ultrasonic simulation using CIVA and experimental verification for thin-walled small-diameter pipe with flaws that were carried out to determine the most appropriate phased array probe and its detection capabilities in this paper.

As microglial activation is a key factor in the pathogenesis of Parkinson's disease (PD), drugs that target this process may help to prevent or delay the development of PD. The present study investigated the effects of dl‑3‑n‑butylphthalide (NBP) on microglia in a lipopolysaccharide (LPS)-induced PD mouse model. The mice were randomly divided into a blank control group, LPS control group and NBP + LPS treatment group. Mice in the treatment group were given an intragastric infusion of 120 mg/kg NBP daily for 30 days during the establishment of the PD mouse model. At 4 and 28 weeks post‑treatment, the motor behaviours of the mice in each group were observed using the rotarod test and the open field test. In addition, immunohistochemical staining was performed to determine the levels of activated microglia, tumour necrosis factor‑α and α‑synuclein, and the number of tyrosine hydroxylase (TH)‑positive cells in the substantia nigra. NBP significantly improved dyskinesia, reduced microglial activation, decreased nuclear α‑synuclein deposition and increased the survival of TH‑positive cells in the substantia nigra of LPS‑induced PD model mice. These findings suggested that NBP may exert its therapeutic effect by reducing microglial activation in a mouse model of PD.

Fc receptor like 3 gene (FcRL3) has been associated with some autoimmune diseases. Here, its role in Guillain–Barre syndrome (GBS) was evaluated by studying nine FcRL3 gene SNPs in a Chinese cohort of GBS patients. The frequencies of FcRL3-3-169C, FcRL3-6 intron3A, and FcRL3-8 exon15G alleles were significantly increased in GBS patients compared with healthy controls. The frequency of FcRL3-1 → 9 CCTGGAGAA haplotype was significantly increased, and the frequencies of FcRL3-1 → 9 CCTACAAAA,CCCACGAAA, and CCTGCGGAA haplotypes were significantly decreased compared with healthy controls. These results suggest that FcRL3 is associated with GBS incidence.