Abstract: In the biological aerated filter, the removal efficiency of phosphorus is poor, while the efficiency of organics and nitrogen are very well. In order to solve these problems, the sequence bio-film reactor connects to traditional biological aerated filter, ceramic filler was added to the system, study the effect of bio-film culturing and biological disposal capacity .Control intermittent time of anaerobic and aerobic and aeration volume, the removal effect of COD 、nitrogen and phosphorus are good in the sewage . The results show that anaerobic and aerated time are 3h and 4h in SBBR, the removal efficiency of COD、NH4+-N、TN and TP are 90.07%、85.12%、81.74% and 83.63%, the concentration are 31.37mg/L, 5.15㎎/L, 6.60㎎/L and 1.10㎎/L separately. All of these satisfy theⅠ-B criteria specified in Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant (GB 18918-2002). The system of SBBR-BAF run stably, removal sewage perfectly, avoid return and mud, save energy consumption.
Abstract: The standard k-ε turbulence model was used to simulate the flow of a new unsmooth surface - dimple concave surface in air and the drag reduction coefficients of both unsmooth surface and smooth surface with hemisphere of 0.4mm radius were presented. The result showed that this kind of unsmooth surface had a good drag reduction effect for flow velocity ranging from 4m/s to 48m /s. And it had the best reducing ability (7.2%) at a velocity of 24 m/s. The theory of the drag reduction was finally analyzed.
Abstract: Water lubricated rubber bearings are one of the most appropriate bearings for underwater use. The most popular design used widely today is the straight fluted rubber bearing. The special configuration leads to partial hydrodynamic lubrication and low load capacity. A new bearing bush structure which is favorable for constructing continuous hydrodynamic lubrication was designed and produced for experiment in the paper. The eccentricity ratio of the new structure rubber bearing was measured under different loads in experiment. Used the measured eccentricity ratios, the load capacity was calculated by numerical simulation and compared with the given test values. The calculated values were in good agreement with the given test results. The results show that complete hydrodynamic lubrication can be formed in the new designed rubber bearing. The experimental results also indicate that there is an appropriate bearing clearance which the load capacity is up to the maximum.
Abstract: The effects of CF content on flexural and tribological properties of the composites were investigated. The worn surface morphologies of neat PTFE and its composites were examined by scanning electron microscopy (SEM) and the wear mechanisms were discussed. The presence of CF particles dispersed in the PTFE continuous phase exhibited superior tribological characteristics to unfilled PTFE.
Abstract: PEI composites filled with glass and carbon fiber was synthesized. The aim of the research article is to study the mechanical and two-body abrasive wear behaviour of glass/carbon fiber reinforced PEI composites. The microstructure of the composite was examined by scanning electron microscopy. The results showed that the highest specific wear rate was for glass fiber reinforced PEI composite was higher than that of carbon fiber reinforced PEI composite.
Abstract: Cast magnesium alloys are constantly increasing used in the automotive and electronic industry because of the excellent performance. Squeeze casting is an innovative and energy-saving manufacturing process which can be used to produce near net-shape magnesium components. In order to improve the quality of the squeeze casting，the different process parameters were adopted to study the forming property of AZ91D alloy by applying multifactor orthogonal test and analysis of range under the laboratory condition. The metal pouring and die temperatures considered in the investigation were within the range of 680-780 and 300°C respectively. The results showed that the samples’ synthetic mechanical properties was the best, and squeeze casting can refine grain and the second phase particle β(Al12Mg17)separated out more by using mechanical properties test and analyzing microstructure when casting temperature is 730°C, squeezing force is 100 Mpa and time of keeping forces 25s.
Abstract: Due to the excellent mechanical properties combined with high strength to weight ratio, honeycomb sandwich panels (HSP) are used increasingly in aerospace, automobile and marine industries. In order to improve the crashworthiness of vehicle body, it is of great significance to study the energy absorption characteristics of the components. For this reason, specific energy absorption (SEA: the energy absorption per unit mass) of HSP was selected to be the objective function in order to find an optimal design of HSP under impact loading. The explicit finite element analysis (FEA) was used to derive response surface (RS) model of SEA, and a single-objective optimization was performed to get the optimal design. Before the optimization design of HSP, the energy-absorptions of HSP and the honeycomb core (HC) were compared with each other. It was found that HSP could absorb much more impact energy than HC due to the stabilizing effect of the face sheets during the process of crushing.
Abstract: Corrosion inhibitor I9602 was synthesized in the laboratory. Infrared spectrum (IR) and ultraviolet spectrum (UV) in conjunction with nuclear magnetic resonance (NMR) had been performed to characterize its structure. Corrosion behavior of N80 steel and inhibition property of I9602 in pH=2 solution including 3% NaCl with carbon dioxide saturated were studied. The results showed that, the corrosion of N80 steel in this solution was quite serious, its corrosion rate was 43.02mm/a. The inhibitor synthesized I9602 was mainly composed of amide and imidazoline. When its concentration in above solution was 150mg/l, the inhibition efficiency of I9602 was 90%, and it had good inhibition effect. Using inhibitor was an economical protective measure.
Abstract: This paper explored the distribution regularities of TiC particles in molten steel under electromagnetic stirring condition. The influencing factors on distribution such as the unit stirring power(P), the styles of TiC particles addition and the methods of surface pretreatment had been studied in our experiments. The results show that it’s easier to get uniform distribution by the way of high-power smelting with miniwatt stirring and the bottom injection. Besides, the pretreatment plays an important role in particles distribution.