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Based on the V-type diesel engine crankshaft system, the paper combined the finite element method (fem) and multi-body dynamics method together, made a virtual simulation analysis. First, by 3d software and finite element software to establish the multi-body dynamic models of the crankshaft, bearing and piston, then simulated the actual engine working condition, and got the data such as crankshaft acceleration, velocity and displacement by the multi-body dynamics simulation analysis. By calculation, the paper found that by using the combination of finite element and multi-body simulation method, can we effectively simulate the diesel engine crankshaft dynamics characteristics.

In the process of calculating the crankshaft frequency and vibration mode, free mode is always applied for the crankshaft modal analysis. Considering the effect of centrifugal force generated by the rotation to the crankshaft frequency and vibration mode, the frequency and vibration mode of multi-speed cases are calculated, and compared, which fully shows the vibration situation of the crankshaft in the process of actual working situations, the results match actual situation.

This paper reports NiO/γ-Al2O3 photocatalysts have well photocatalytic degradation capacity. NiO/γ-Al2O3 catalysts were prepared by Ni(NO3)2•6H2O,γ-Al2O3 with the impregnation method, and treated by the plasma-assisted, which were characterized by XRD, FT-IR,BET and other analytical tools. The influence factors of methyl orange degradation efficiency were analyzed under the 250W high-pressure mercury lamp.

Ba(Ti0.95Sn0.05)O3 ceramics were prepared using BaCO3, SnO2 and TiO2 et al as crude materials, La2O3 as dopant, and their dielectric properties are investigated. The morphology analysis of sintered samples was conducted by SEM. It is found that for 0.1 wt% La2O3 doped BTS5 ceramics sintered at 1290oC has the highest dielectric constant. It can also be seen that the samples sintered at 1260oC have higher dielectric loss, which can result from the existence of the pore. Meanwhile, in the terms of dielectric loss, 0.1 wt% La2O3 doped BTS5 ceramics has lower value and the dielectric loss is more stable with temperature varying.

A sequencing batch reactor was employed to treat ammonia wastewater, the pH, DO and OUR were adopted to monitor the start of short-cut nitrification. The results showed that the start of short-cut nitrification was achieved in 31days, ammonia consumption rate was higher than 90% and nitrite accumulation rate was higher than 85%, when pH, DO and OUR were applied to monitor and determine the aeration time, under the condition of temperature was 30°C. With ammonia shock loading conditions, OUR curve couldn’t indicate the end of short-cut nitrification exactly. But real-time control using pH and DO could achieve a stable shortcut nitrification under steady stage and ammonia load shocking stage.

Based on the complexity of surface vibration of diesel engine, the wavelet denoising method is used to process the monitor signal Preliminary. And then several vibration modes are isolated based on EMD method. Finally take the energy of these vibration modes as the input parameters to create neural network for fault diagnosis of diesel engine valve. The method has accomplished the fault diagnosis of the diesel engine merging many methods.

Ba0.62Sr0.38TiO3 ceramics of perovskite structure are prepared by solid reaction method with the addition of x wt% NiO and their dielectric properties are investigated. It is found that Ni2+ can enter the B site in ABO3 perovskite when doping concentration is less than 0.6 wt%, whereafter, Ni2+ ions most segregates on the grain boundaries to inhabit the grain growth. Due to the decrease of grain size and the impurity, the dielectric constants are decreased. Decrease of dissipation factor is attributed to appearance of the oxygen vacancy and disappearance of the reduction of Ti4+ ion. It is concluded that the diffuse phase transition is linked to the adulteration of Ni2+. The disordering, mechanical stress in the grain and the oxygen vacancies are produced because of the adulteration of Ni2+, and the diffuse phase transition increases with the level of doping increasing, leading to that the peaks of dielectric constants becomes slower and flatter.