Aiming at the problem in dynamic leakage of urban overhead gas pipeline,considering the impact of different pressure levels on leakage and diffusion, high pressure (2.0 MPa), sub high pressure (1.0 MPa) and medium pressure (0.4 MPa) three kinds of pressure grade pipe to simulate were selected.Firstly, the leakage rate of the critical flow and the sub critical flow were calculated by using the leakage rate calculation mode.Secondly, the leakage rule of different pressure pipelines was obtained.The Fluent software was used to simulate the unsteady state leakage, and the risk range of natural gas diffusion was obtained.The results showed that if the pressure in the tube was greater,the quality of residual gas in pipe and the time of leaking was higher and the risk range of natural gas was lager when the volume of pipe and the diameter of leak were fixed.With the continuous leakage of non steady state, the leakage rate was getting smaller and smaller, the risk of natural gas was also getting smaller and smaller.

This paper studied the preparation of a kind of environmentally friendly aluminum alloy wire passivation solution. During the experiments, the composition of the passivation solution has been studied, and the optimum content of each component has been achieved. In addition, the effect of passivation technical conditions on the passivation performance has been examined. The results show the optimal composition of passivation solution as follows: 6%~8% of w(sulfuric acid), 4%~6% of w(sodium sulfate),6×1 0-4~8×1 0-4、 of w(copper sulfate), and 2%~3% of w(urea); the optimal passivation technical condition is: passivation temperature 30~40 ℃, and passivation time 10~20 s.For the aluminum alloy wire,the performance of the passivation solution was comparable to the chromate passivation solution passivation.

The relation of oil removal rate from aluminium alloy surface and NaOH concentration, solution temperature, soak time and stirring intensity was studied. With orthogonal test, the process conditions were optimized. In test conditions, the order from big to small of influence factors is:the reaction temperature,soak time,NaOH concentration,stirring intensity. The optimized process conditions are as follows: solution temperature 60 ℃, soak time 20 min, NaOH concentration 90 g/L and stirring intensity 400 r/min. Under the optimized process conditions, the oil removal rate reaches above 99%.

The application of data mining in CRM (Customer Relationship Management) is a hot spot in recent years. CRM refers to the enterprise's approach to understand and influence customer behavior through meaningful communications in order to improve customer acquisition, customer retention, customer loyalty, and customer profitability. Adopting different services to different customers is based on the accumulation of vast amounts of data by the enterprise. The effective way to get the knowledge from these data is the technology of DM (Data Mining), which will provide basis for leader's decision-making, and achieve the objectives of CRM. The basic theory of the customer relationship management and data mining technology, and the application of DM in petrochemical enterprise CRM were discussed.