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Lung cancer is one of the highest incidence rate and mortality rate in the world. Lung nodule is an early manifestation of lung cancer. Therefore, the early detection of pulmonary nodules is of great value in preventing lung cancer. At present, the target detection method of deep learning is widely used in medical image processing. In order to improve the efficiency and accuracy of pulmonary nodule detection, and reduce the missed diagnosis rate and misdiagnosis rate of pulmonary nodule, this paper proposes a pulmonary nodule detection method based on improved yolov3. This method first proposes to use the superimposed extended convolution, and then processes the 104 * 104 feature map output from the second residual block in darknrt-53, which is the backbone feature extraction network of yolv3, and the superimposed extended convolution. Finally, after twice down sampling and 52 * 52 detection feature map fusion, a new 52 * 52 detection feature fusion map is formed to improve the network feature extraction ability. A large number of experiments were carried out on luna16 open lung CT image data set. The experimental results show that the average accuracy of the improved model is improved from 70.5% to 73.9%, and the convergence effect of the improved model is better than that of the original model.

The high temperature deformation behaviors of low-carbon steel QD08 were investigated by hot compression tests over temperatures from 1000°C to 1200°C and strain rates from 0.1 to 10 s −1 . In order to describe the flow characteristics, a constitutive equation was developed and the relation between the flow stress and Zener–Hollomon parameter was successfully analyzed via the hyperbolic sine function under the whole range of deformation condition. It can be found that the critical strain ε c increases with parameter Z increasing; the critical conditions for onset of dynamic recrystallization is ε > ε c = 61 . 9381 Z 0 . 1033 . Based on dynamic material model and Prasad’s instability criterion, the power dissipation map and the instability map were developed. The results show that the security domain of hot deformation for low-carbon steel QD08 at the temperature range between 1070°C and 1100°C, and strain rate range of around 5–10 s −1 , with a higher power dissipation factor, maintains a smooth variation, under stable deformation conditions. On the basis of processing map, the optimal deformation processing parameters are the hot deformation temperature range from 1070°C to 1100°C, and strain rate range from 5 to 10 s −1 .

Summary Pea starch (PS) appears to be very attractive for the peculiar physicochemical characteristics, which is used for the vermicelli, film-forming material due to the high amylose content. The aim of this study was to optimise the hydroxypropylation technology parameters of the microcrystalline pea starch based on pea starch as a raw material, hydrochloric acid as an hydrolysis reagent, epoxy propane as an etherisation reagent by the Box–Behnken method. The thermal properties of hydroxypropylated microcrystalline pea starch were characterised by the thermogravimetric analyser and differential scanning calorimeter, respectively. Through the analysis of Design-Expert software, the regression model and corresponding variances were obtained. In this case, the determination coefficient (R2) was 0.9631. This implied that 96.31% of the variation could be explained by the regression model. The best reaction conditions for preparing the hydroxypropylated microcrystalline pea starch were as follows: reaction temperature 40 °C, reaction time 16 h, amount of epoxy propane 14%, amount of sodium hydroxide 1.2% and amount of anhydrous sodium sulphate 12%. After the microcrystalline pea starch was hydroxypropylated, its peak temperature, melting enthalpy, temperature range of the endothermic peak increased, but its the thermal stability, onset temperature decreased.

This paper reports that the lead zirconate titanate (PZT) piezoelectric composites incorporating zinc oxide nanowhiskers (ZnOw) were prepared by the conventional solid state processing. The whisker-dispersed PZT composites (PZT/ZnOw) presented a significant enhancement in the mechanical properties such as Young's modulus, tensile strength and compressive strength. Especially, the compressive strength increased from 153 MPa for the PZT to 228 MPa for the PZT/ZnOw composites. The reinforcement mechanism in strength of the composites was discussed. The mechanical quality factors of the PZT/ZnOw composites increased considerably, while the piezoelectric constants and electromechanical coupling coefficient decreased slightly. The composites with good electrical and excellent mechanical properties are promising for further applications.

The electrocatalytic oxidation and degradation of phenol and aniline were studied at Ti/SnO2-Sb2O5 electrode by UV-Vis spectroscopy and high performance liquid chromatography (HPLC). It is shown that hydroquinone, benzoquinone and maleic acid are the same intermediates and products during oxidation of both aniline and phenol. This indicates that the oxidation of the two compounds probably has the same degradation routes. The electropolymerization of anilines results in different oxidation and degradation course of aniline and phenol.