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Based on the reverse uniaxial loading test, the influences of the plastic deformation on the strength properties are studied. The softening of the X80 pipeline steel is observed which reveals the hardening type is mixed hardening. The expression of mixed hardening factor M and the material parameters of the nonlinear mixed hardening model under different M can be obtained. The results show that, if the pre-strain increases and ranges from 0.55% to 2.5%, the mixed hardening characteristics of the X80 pipeline steel will be more obvious and its M will also increase.

In upsetting forging process of the crank of crankshaft the defects such as lap and caving probably occurs since the bending and upsetting is not in good coordination. In this paper, aiming at 305 crankshaft for marine engine, the coordinative relation between bending and upsetting was thoroughly studied based on 3-step crank upsetting forging approach, i.e. bending-upsetting, upsetting and finish forming. Numerical simulation was carried out to find the reasonable stroke matches of bending and upsetting and physical experiment of using lead sample reduced at the ratio 1:6 in size was conducted to verify the match scheme gained from numerical simulation. The result found from numerical simulation is in good accordance with the one gained through experiment. The work in this paper provides theoretical basis for practice of upsetting forging technique of crank.

Roll-over of crank arm is the major defect of forming quality during the upsetting process. Bending and upsetting forging of crankshaft was simulated by using the rigid-plastic finite element model. The theories of metal flowing and distribution of deformation during the bending and upsetting forging were analyzed, the root cause of the roll-over of crank was found; the optimal combination of the bending and upsetting velocities was obtained; the experimental results agree well with simulations.

Chemoresistance is a major cause of treatment failure in patients with lung cancer. Although the extensive efforts have been made in overcoming chemoresistance, the underlying mechanisms are still elusive. Cancer cells reprogram cellular metabolism to satisfy the demands of malignant phenotype. To reveal roles of cancer metabolism in regulating chemoresistance, we profiled the metabolic characteristics in paclitaxel-resistant lung cancer cells by flux assay. Glucose and oleate metabolism were significantly different between resistant and non-resistant cells. In addition, targeting metabolism as a strategy to overcome drug resistance was investigated using specific metabolic inhibitors. Inhibition of glycolysis and oxidative phosphorylation by 2-deoxyglucose and malonate, respectively, potentiated the effects of paclitaxel on nonresistant lung adenocarcinoma cells but not paclitaxel-resistant cells. By contrast, inhibition of lipolysis by mercaptoacetate or etomoxir synergistically inhibited drug-resistant lung adenocarcinoma cell proliferation. We conclude that lipolysis inhibition potentially be a therapeutic strategy to overcome drug resistance in lung cancer.