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Objective To investigate the inhibition of house dust mite induced oxidative stress with human bronchial epithelial cell line BEAS-2B by aldose reductase inhibitor (ARIs). Methods BEAS-2B was divided into control group, model group, NF-κB inhibitor group (PDTC group) and ARIs intervention group (ARIs group). Oxidative stress reaction (MDA and ROS content, SOD activity) was detected by ELISA. The contents of IL-5, IL-13 and IFN-γ were measured by ELISA. MTT was used to detect cell viability. Cell apoptosis was detected by flow cytometry. The expressions of NF-κB, NF-κB P65 and P38 MAPK proteins were detected by Western blot. Results SOD activity, IFN-γ content and cell survival rate in model group were lower than those in control group (P＜0.05), MDA, IL-5, IL-13 content and cell apoptosis rate were higher than those in control group (P＜0.05). Compared with model group, SOD activity, IFN-γ content and cell survival rate in PDTC and ARIs groups were increased(P＜0.05), MDA, IL-5, IL-13 content and cell apoptosis rate were decreased (P＜0.05). Compared with control group, the expression of NF-κB, NF-κB P65 and P38 MAPK protein in model group was significantly increased(P＜0.05). The expression of NF-κB, NF-κB P65 and P38 MAPK protein in PDTC group and ARIs group were significantly decreased (P＜0.05). Conclusions Aldose reductase inhibitors improve the oxidative stress response of human bronchial epithelial cells induced by house dust mites, promote the proliferation of BEAS-2B cells and inhibit apoptosis.

Focusing on the influence of notch on the multiaxial fatigue performance of material, the proportional multiaxial fatigue test was carried out on 7075-T651 aluminum alloy thin-walled notched specimens with variable equivalent stress amplitude. The digital image correlation technique was used to characterize and analyze the critical plane angle. The results show that with the increase of the equivalent stress amplitude, the multiaxial fatigue life of the specimen decreases, and the maximum axial, torsional and shear engineering strains near the notch increase. Under different loading conditions, the strain concentration near the notch increases with the increase of loading cycles. The process of strain change near the notch can be divided into crack initiation, crack growth and instantaneous fracture stages. By introducing the critical plane angle and the maximum positive strain on it, a modified SWT model is proposed. Fine life prediction results are obtained by the modified model with all predicted data in the two scatter bands.

The metal surface anti-corrosion technology has always been the focus of attention in the field of industrial engineering. With the advancement of science and technology and the consideration of environmental protection, its green environmental protection requirements have gradually become one of the important indicators of the current metal surface anti-corrosion technology. In this paper, in order to study the research progress of green anti-corrosion coating technology on metal surface in recent years, based on a large number of domestic and foreign literatures, the classification, characteristics and application of membrane technology and anti-corrosion mechanism of three typical new technologies in metal surface anti-corrosion coating, i.e. self-assembled monolayers(SAMs) technology, corrosion inhibitor and molecular sieve membrane technology were reviewed. At the same time, other feasible green anti-corrosion coating technologies such as coating additives and graphene coatings and the developing trend of self-assembled monolayers, corrosion inhibitor and molecular sieve membrane technology in system construction, process optimization and composite coating design and etc are pointed out.

The metal surface anti-corrosion technology has always been the focus of attention in the field of industrial engineering. With the advancement of science and technology and the consideration of environmental protection, its green environmental protection requirements have gradually become one of the important indicators of the current metal surface anti-corrosion technology. In this paper, in order to study the research progress of green anti-corrosion coating technology on metal surface in recent years, based on a large number of domestic and foreign literatures, the classification, characteristics and application of membrane technology and anti-corrosion mechanism of three typical new technologies in metal surface anti-corrosion coating, i.e. self-assembled monolayers(SAMs) technology, corrosion inhibitor and molecular sieve membrane technology were reviewed. At the same time, other feasible green anti-corrosion coating technologies such as coating additives and graphene coatings and the developing trend of self-assembled monolayers, corrosion inhibitor and molecular sieve membrane technology in system construction, process optimization and composite coating design and etc are pointed out.

Tension-torsion fatigue tests with different loading conditions were carried out on 7075-T651 aluminum alloy thin-walled tubular specimens aiming at studying multiaxial fatigue failure of aviation aluminum alloy. With the decrease of equivalent stress amplitude, the multiaxial fatigue life increases. Under the same equivalent stress, the multiaxial fatigue life is prolonged as the stress amplitude ratio augments while the tension-torsion phase has little effect on fatigue life. Under high stress amplitude, the materials are mainly softened in the axial and torsional directions while the hardening and softening alternately occur under the low stress amplitude. The platform area of macro fracture decreases with the increase of stress amplitude ratio. The microscopic fracture exhibits the multiple crack sources outside the wall of the tube. Fatigue striations and secondary cracks can be observed in the crack propagation region. Mixed mode dimples appear in the instantaneous fracture region. Based on Basquin's criteria, a modified model was proposed, and fine life prediction results were obtained, with the life prediction values in 2X scatter bands.

The crack initiation and propagation of 7A04 aluminum alloy in 3.5%NaCl solution at pH=1,4,7,12 during slow strain rate test (SSRT) were investigated by the method of combining phase shift with electrochemical impedance spectroscopy. The feasibility of the method was verified by electrochemical noise (EN). The results show that the more corrosive the solution is, the susceptibility of the 7A04 aluminum alloy to stress corrosion cracking is greater;in the solution at pH=1,the phase shift method shows that crack initiates at 1h and propagates at 4.5h,and the electrochemical impedance spectroscopy in situ method shows the crack initiation and propagation are discontinuous,and in stages;the EN results show that the crack initiation occurs at a certain moment among 3000-5000s and propagates obviously at a certain moment among 13500-22500s accompanying with obvious periodical current and potential noise peaks.