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The ultra-thick wall steel pipes are very likely to have quality defects in stretch-reduction hot rolling process, and it is preferred to study these defects by simulation methods. However, traditional FEM often has the problems of convergency difficulty and time consuming for solving complex large deformation problems. Therefore, in this study, a mixed explicit-implicit FEM, was adopted for solving the thermo-mechanical coupled process of the stretch-reduction hot rolling. Multidimensional heat transfer as well as mechanical boundary conditions were acted simultaneously, and the accuracy of the model was validated by industrial experiments. Results showed that the simulation results are very consistent with the actual rolling results. Three typical rolling defects were accurately predicted, i.e., inner hexagon, thickened ends and linear mark. Besides, it is discovered that the uneven distributions of stress, strain and temperature are important causes for the rolling defects, and these influences are also presented and discussed. This paper presents an efficient and precise numerical modelling method so as to provide theoretical guidance for the production of ultra-thick wall pipes.

Near infrared spectroscopy analysis, as a kind of nondestructive real-time continuous detection method, has provided ideas for the noninvasive measurement of blood components. In this article, in order to ensure the accuracy and reliability of the collected spectral data, the 405 acquired samples are evaluated by combining valid single edge counts of dynamic spectrum pulse wave in the time domain with the quality factor Q value of dynamic spectrum pulse wave in the frequency domain. As a result, the abnormal samples are removed and 218 cases of valid samples are selected. We use the dynamic spectrum data of the selected 218 samples as the experimental group and another 218 samples as a control group modeling analysis with the hemoglobin concentration of the corresponding samples. Each group select 200 cases of samples as a calibration set and 18 cases of sample as a prediction set. The prediction accuracy of the experimental group reach 93.8%. The prediction accuracy of the two control group respectively evaluated by the valid single edge counts or Q value are 65.6% and 67.7% and the three unfiltered control groups are 53.7%, 33.3%, 42.6% respectively. The prediction mean relative error (MSEP) of the experimental group is 0.067 5, the other two control groups are 0.072 3 and 0.072 2, and the other three control groups are 0.082.3, 0.078 9, 0.082 8. So compared with another control groups, the MSEP of the experimental group is the minimal. The results show that the filtering method of the spectral data samples through combining time domain with frequency domain is reliable and effective.this will provide a method to the precision research of dynamic spectrum noninvasive detection.

Along with the popularization of artificial intelligence and information technology, the development of automobile industry have been closely combined with information technology, environmental protection and energy saving ideas, promotion and application of electronic control technology, which development cycle becoming shorter and shorter. In this paper, through the analysis of the present application situation and development trend of the automobile electronic technology at present, in order to provide a theoretical reference for the future development of the automobile electronic control technology.

The objective of this study was to determine the influence of chinonin on acute hypoxic pulmonary vasoconstriction (HPV) in Sprague-Dawley (SD) rats and investigate its mechanism. Sixty-five SD rats were divided into five groups at random: six in the control group; six in the hypoxia group; 13 in the group of hypoxia with chinonin; 20 in the group of endothelin-1 (ET-1) with chinonin and 20 in the group of platelet activating factor (PAF) with chinonin. Their mean pulmonary arterial pressures (mPAP) were measured and the concentration of molondialdehyde (MDA) in plasma and the activity of phospholipase A2 (PLA2) of the lung tissues were detected. The PAF and ET-1 levels of plasma and lung homogenates were detected in the control and hypoxia groups. There was evidence of an increase in mPAP, MDA, PAF and ET-1 in the plasma, and activity of PLA2, PAF and ET-1 of the lung tissues when the rats inhaled a 10% mixture of oxygen in nitrogen. It appeared that chinonin may have been inhibiting the action of ET-1 and PAF. Chinonin could have prevented an increase in MPAP caused by hypoxia and inhibited the action of ET-1 and PAF. But chinonin had no influence on the increase in MDA in the plasma and the PLA2 activity of the lungs when hypoxia occurred. Chinonin can reduce HPV, but does not influence normal mPAP. It may do this by blocking the action of ET-1 and/or PAF or others. The definite mechanism needs to be studied further.

AIM: To investigate the morphology of lymph vessel capillaries in both human gastric carcinomas and their peritumoral tissues, as well as the relation of this morphology to lymphatic metastasis. METHODS: The morphology and fine distribution of both lymph vessels and capillaries in and around the primary foci of gastric carcinoma were studied using the 5′Nase Alpase double staining method. The total amount of opened vessels and the opening rate of lymph vessels and capillaries were counted using a light microscope (100 × magnification), and the maximal luminal area, perimeter and diameter were measured using an image analysis technique. RESULTS: Lymph vessels and capillaries displayed strong 5′Nase-positive staining (brown and dark brown), while blood vessels and capillaries revealed significant Alpase activity (blue). There were many lymph vessels, capillaries and solid strip-like tissues found in the gastric carcinoma samples analyzed. The total amount of lymphatics in the metastatic group (gastric carcinoma vs peritumoral tissue) and non-metastatic group was 26.9 ± 14.2 vs 10.4 ± 4.0, 11.4 ± 3.4 and 9.7 ± 3.2, P < 0.01, respectively. Their opening rates were 21.2 vs 47.5 and 40.4 vs 46.0, P < 0.01, respectively. Their maximal luminal areas were 1502.98 ± 1236.91 vs 5526.80 ± 4853.42; 1918.14 ± 2299.24 vs 3836.16 ± 3549.16; 5526.80 ± 4853.42 vs 3836.16 ± 3549.16, P < 0.05, their perimeters were 220.33 ± 130.25 vs 441.43 ± 276.51; 241.79 ± 171.13 vs 333.80 ± 199.66; 441.43 ± 276.51 vs 333.80 ± 199.60, P < 0.05, and their diameters were 28.80 ± 14.98 vs 59.39 ± 28.53; 25.37 ± 15.79 vs 46.22 ± 20.85; 59.39 ± 28.53 vs 46.22 ± 20.85, P < 0.05, respectively. In summary, the lymphatics found in gastric carcinoma samples from the metastatic group were significantly lower than those of the other groups. CONCLUSION: There are newly formed lymph capillaries found in gastric carcinoma. Dilation of lymph capillaries may be related to edema found in peritumoral connective tissues. The observed lymph node metastases from gastric carcinoma occur through mature lymph capillaries that invade in and around primary gastric carcinoma foci.