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We constructed two novel multifunctional copper complexes as efficient catalysts for the OER and photocatalytic degradation of azo dyes.

We constructed eight MOFs with semiconductor behavior, discussed their structures in detail, and explored their practical applications.

Hot compression tests of T24 ferritic steel were carried out using Gleeble-3500 thermo mechanical simulator in the temperature range of 1323–1473 K with the strain rate of 0.01–10 s−1 and the height reduction of 60%. The flow behavior of T24 ferritic steel was characterized based on analysis of the true stress–strain curves. Constitutive equations incorporating the effects of temperature, strain rate and strain have been developed to model the hot deformation behavior of T24 ferritic steel. Material constants α, n, ln A and activation energy Q in the constitutive equations were calculated as a function of strain. The flow stress values of T24 ferritic steel predicted by the proposed constitutive equations show a good agreement with experimental results, which indicated that the developed constitutive equations could give an accurate and precise prediction for the flow stress of T24 ferritic steel.

The true stress–strain data from isothermal hot compression tests on Gleeble-3500 thermo mechanical simulator, in a wide range of temperatures (1323–1473 K) and strain rates (0.01–10 s−1), were employed to establish the constitutive equations based on modified Zerilli–Armstrong and strain-compensated Arrhenius-type models respectively, and develop the artificial neural network model to predict the high-temperature flow stress of T24 steel. Furthermore, a comparative study has been made on the capability of the three models to represent the elevated temperature flow behavior of this steel. Suitability of the three models were evaluated by comparing the accuracy of prediction of deformation behavior, correlation coefficient and average absolute relative error of prediction, the number of material constants, and the time needed to evaluate these constants. The results showed that the predicted values by the modified Zerilli–Armstrong model could agree well with the experimental values except under the strain rate of 0.01 s−1. The predicted flow stress of the other two models shows good agreement with the experimental data. However, the artificial neural network model could track the deformation behavior more accurately throughout the entire temperature and strain rate range though it is strongly dependent on extensive high quality data and characteristic variables and offers no physical insight.

The true stress–strain data from isothermal hot compression tests, in a wide range of temperatures (1173–1473 K) and strain rates (0.01–10 s −1 ), were employed to study the deformation behavior and develop constitutive equation of V150 grade oil casing steel based on an Arrhenius-type equation. The flow stress increases with the decrease of deformation temperature and the increase of strain rate, which can be represented by Zener–Hollomon parameter in an exponential equation. The influence of strain was incorporated in the developed constitutive equation by considering the effect of strain on material constants. The flow stress predicted by the constitutive equation shows good agreement with the experimental value through the whole experimental temperature and strain rate range except a slight deviation for predicting the stress deformed at 1173 K under 0.01 s −1 , and the average relative error is 4.21%.

The continuous rolling and sizing processes for producing non-quenching and non-tempering 36Mn2V steel pipes used in oil well were studied by the thermomechanical simulation test in this paper. The results showed clearly that the final microstructure was influenced by deformation temperature and stain applied. When continuous rolling temperature was controlled at 1050°C and strain at about 0.5 or above, dynamic recrystallization was completed and fine austenitic grain was obtained. When sizing temperature was controlled at 850°C or below and strain at about 0.2 or above, fine acicular ferrite was obtained with properties satisfying the requirement of the high quality pipe. The results of the study provided reliable data for the controlled rolling and sizing processes for the production of the 36Mn2V steel pipes.

the aid of commercially available software MSC.SuperForm, a 3-D finite element model has been established to simulate the rolling process of steel tubes on the stretch reducing mill (SRM) with group centralized differential drive in certain factories. A special effort was made to analyze the fluctuation of transverse wall thickness uniformity. It was found that the wall thickness of each stand was accumulated in the original pass 50°~60° along the circumferential direction, which caused the formation of the inner hexagon defects and worsen. In view of this, this paper proposes a modified roll pass design method which uses the interactive technology of CAD graph curve and MATLAB equation. By means of decreasing the lateral curvature of roll pass contour curve to enlarge the contact length between the tube and groove, also the rolling process using the new pass system were simulated and analyzed. The results indicate that the design of such polygonal roll pass can be effective in improving the inner hexagon defects.