Xuzhou Institute of Technology

About: Xuzhou Institute of Technology is a education organization based out in Xuzhou, China. It is known for research contribution in the topics: Catalysis & Adsorption. The organization has 1696 authors who have published 1521 publications receiving 13541 citations.

Finite Element Analysis for Temperature Field of Laser Remelting Plasma Sprayed Ni-Based Gradient Coating on Ti6Al4V Alloy Surface

Abstract: In order to acquire evolution law of temperature field of laser remelting plasma sprayed Ni-based gradient coating on Ti6Al4V alloy surface，the effects such as heat conduction, heat radiation, heat convection ,phase change and materials highly non-linearity on coatings and substrate are taken into account comprehensively, and a 3D finite element model(FEM) of multi-tracks laser remelting temperature field is established. The analysis results show that mechanical bonding between coatings and substrate change into metallurgical bonding on present processing parameter，the depth of alloy belt vary in each scanning track and the average depth of alloy belt become deeper gradually with the increment of scanning lines. Temperature changing regular of different points on scanning tracks along scanning direction is similar. Temperature become higher and higher in succeeding scanning tracks due to the heat accumulation effect in laser remelting process. The cooling rate on the mid-points of each scanning track reaches 1200 /s above. The thermal gradient from coatings to substrate along Z direction is absolutely predominant compared with that along X,Y direction, so heat dissipates mainly along the direction normal to substrate which help to crystal grain grown preferentially.

Multi-objective Robot Path Planning based on Bare Bones Particle Swarm Optimization with Crossover Operation

Abstract: This paper proposes an improved multi-objective robot path planning based on bare bones particle swarm optimization and crossover operation of Genetic algorithm. First, the path planning is mathematically formulated as a constrained multiobjective optimization problem with two indices, i.e. the path length and the safety degree of a path. Then, a multi-objective bare bones particle swarm optimization combined with crossover operation is developed to solve the above model. Aiming at the infeasible paths blocked by obstacles in evolution, three modified crossover operations, i.e. multi-point crossover, uniform crossover and arithmetic crossover, are designed to improve the feasibility of an infeasible path. Finally, simulation results confirm the effectiveness of our algorithm.

Research on the stabilization of friction torque of precision ball screw

Abstract: Taking into account the influence of the error in the contact points of balls and the groove on the contact force, the influence of manufacturing errors of grooves on friction torque was analyzed. The view that the manufacturing errors of groove in ball screw mechanism affect the value of the friction torque averagely was brought forward. The characteristic of fiction torque of three type ball screws included inner-return type, return pipe type and end cap type was investigated through the friction torque test. The influence of lubrication on the stabilization of fiction torque of ball screw was also investigated through the tests. It was found that the fluctuation of the friction torque at the normal frequency of 1Hz could be eliminated completely when the ball screw mechanism is lubricated by grease. Analysis indicates that the fluctuation of the friction torque at the normal frequency of 1Hz is resulted from the jam and fall off of balls because of poor lubrication.

4′-O-methylpyridoxine: Preparation from Ginkgo biloba Seeds and Cytotoxicity in GES-1 Cells

Abstract: Ginkgo biloba seeds are wildly used in the food and medicine industry. It has been found that 4'-O-methylpyridoxine (MPN) is responsible for the poisoning caused by G. biloba seeds. The objective of this study was to explore and optimize the extraction method of MPN from G. biloba seeds, and investigate its toxic effect on human gastric epithelial cells (GES-1) and the potential related mechanisms. The results showed that the extraction amount of MPN was 1.933 μg/mg, when extracted at 40 °C for 100 min, with the solid-liquid ratio at 1:10. MPN inhibited the proliferation of GES-1 cells, for which the inhibition rate was 38.27% when the concentration of MPN was 100 μM, and the IC50 value was 127.80 μM; meanwhile, the cell cycle was arrested in G2 phase. High concentration of MPN (100 μM) had significant effects on the nucleus of GES-1 cells, and the proportion of apoptotic cells reached 43.80%. Furthermore, the Western blotting analysis showed that MPN could reduce mitochondrial membrane potential by increasing the expression levels of apoptotic proteins Caspase 8 and Bax in GES-1 cells. In conclusion, MPN may induce apoptosis in GES-1 cells, which leads to toxicity in the human body.