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With the rapid development of reinforced earth technology, different reinforced materials are also gradually applied to Reinforced earth. In this paper, we focus on the need for the study of interface characteristics between different reinforced materials and clay, by making indoor drawing test with two kinds of reinforced materials commonly used in engineering and the same clay. The test results show that: the drawing strength between the two reinforced materials and clay both increase with the normal stress increasing, both of their strength envelopes are straight lines; In the drawing test between the warp knitted geogrid and clay, the cohesive strength is 6.65kPa, the friction angle is 21.03°; while the drawing test between the geonet and clay, the cohesive strength is 2.9kPa, the friction angle is 10.96°; The average tensile strength of warp knitted geogrid is 26.4% of genet's, while the drawing strength of warp knitted geogrid in the test is about 48.1% of genet's, so when chosing reinforced materials in some engineerings, it is an important factor that we must consider the particle size and gradation of the filled reinforced materials, selecting the most appropriate size effect.

The landfill leachate belongs to typical high concentration and organic pollutant wastewater. In this study, Landfill leachate was treated with Catalytic Wet Air Oxidation (CWAO) method. The monitoring indicators consist of CODCr, absorbance, pH and chroma. The results show that the activity of the catalysts arrange from high to low: Co (NO3)2, Cu (NO3)2, Fe (NO3)3, CuSO4, Fe2(SO4)3, Mn (NO3)2, FeSO4, Zn (NO3)2, Bi (NO3)3, Zr (NO3)2, Ni (NO3)2; For the same kind of metal, the catalytic activity of nitrates is higher than that of sulfates; Relative to the distribution of catalyst, the activity of Co (NO3)2 is the strongest. With the optimized catalyst Co (NO3)2 , the landfill leachate has been treated. With the extension of reaction time, the effluent CODCr, absorbance and chroma reduced, but the wastewater biodegradability indicator B/C improved. At the reaction time of 90 min, the CODCr of landfill leachate reduced to 7176 mg/L, and the absorbance and the chroma reduced to 9.1 and 1600 times, respectively. The above results show that the activity of catalyst Co (NO3)2 is high, and the biochemical indicators B/C of wastewater is higher than the critical value of 0.3. Therefore, the treated wastewater shows the good biodegradability, and the chosen catalyst of Co (NO3)2 presents the high activity.

Catalytic Wet Air Oxidation (CWAO) is one of advanced oxidation methods about organic wastewater treatment, and the treatment effect of high concentration organic wastewater is remarkable with this method. In this study, the influence factors of the reaction temperature, the reaction pressure and the influent pH were researched on the treatment of the printing and dyeing wastewater with Cu-Fe-La/FSC catalyst, by the single factor experiments and Catalytic Wet Air Oxidation (CWAO) method. Then the catalysts were evaluated by two aspects of the activity and stability. The results show that: with the increase of the reaction temperatures and the reaction pressures, and with the decrease of the influent pH, the CODCrremoval rate improved and the effluent pH reduced. However, the amount of dissolution catalyst components increased with the improvement of treatment effect and the extension of reaction time. By weighing the activity and stability of the catalysts, the optimized reaction temperature, the reaction pressure and the influent pH are 180 °C, 2.5 MPa and 7.25, respectively. Under the optimized operating conditions, the printing and dyeing wastewater with CODCrof 2000 mg/L reaches the CODCrremoval rate of 78.2%, and the dissolvedC[Cu] andC[Fe] of the catalysts are 12.2 and 10.9 mg/L, respectively. Therefore, the catalyst Cu-Fe-La/FSC presents the high activity and stability.

This paper mainly studied the collision between heavy truck and rigid guardrail. The integral finite element models were established via respectively building the finite element model of truck and rigid guardrail and setting parameters of head-on collision. Then the paper did relative simulation and calculation, and analyzed the curves of vehicle speed, accelerated speed and energy in collision process. The whole process above used LS-DYNA to calculate, ANSYS to do pretreatment and LSPREPOST to do post-treatment in order to test collision safety. Compared with relative documents, the established model is basically correct and accords with the regular pattern of collision simulation.

Poly (amidoanime) (PAMAM) dendrimers contain numerous amino-terminal groups and are highly hydrophilic. These terminal groups make PAMAM molecules adsorbed onto graphene oxide (GO) nanosheets through electrostatic action with oxygen containing groups on graphene oxide nanosheets. The PAMAM molecules react with GO, and form stable aqueous suspension of modified reduced graphene oxide (RGO).

An green method to reduce graphene oxide (RGO) was developed by using polysaccharide as both a reducing agent and a stabilizing agent. The RGO was characterized and the factors that affect the reduction of graphene oxide (GO) were explored to obtain optimum reaction conditions. Analysis shows that GO can be reduced at a comparatively low temperature by polysaccharide and forms a stable RGO aqueous dispersion owing to the dispersion of polysaccharide. This approach provides a new green method for GO reduction that has great value for graphene applications.

Investigated the influence of absorbency, turbidity and suspended substance in printing wastewater treatment by regulating the pH value of water treatment. Firstly, was acidified the wastewater samples to 5, 4, 3, 2, then alkalize them to 8、9、10、11、12. Calculated decolorization removal, turbidity removal and the suspended substance removal. The results show that, the decolorization removal and the turbidity removal were low after acidification. While after alkalized treatment the decolorization removal and the turbidity removal were all rise. The decolorization removal and turbidity removal increased following with the increase of pH of samples that first acidified and then alkalized. And it was the most obvious when the pH was 12. When the wastewater samples first acidized the pH to 4 and then alkalized the pH to 12, the dispose effects was the best. In these conditions, the decolorization removal and turbidity removal could reach 57.7 % and 72.8 %. After acidification, the suspended solids removal came down followed with the rise of pH value. As the water samples in same acidification value and then alkalized, with the increase of pH, the suspended solids removal first rose and then came down. It could get the best dispose effects at the pH 11, the suspended solids removal could reach 41.4 %.

Succade wastewater, which was produced in manufacturing process, was treated with two kinds of coagulating agents PAC and ferrous sulfate. The influences of pH, concentration of coagulating agent on COD value, turbidity have been studied. The results of the experiments have shown that for ferrous sulfate, there is an obvious positive correlation, but no significant relation with turbidity removal rate was presented in the statistics; As for PAC, the turbidity declined significantly as PAC dosage increases, only when pH=5 that COD removal rate shows a clear positive correlation with PAC dosage.

Sudden water pollution incidents are incidents that the pollutants affected by some unexpected factors following into water bodies, resulting in contamination of water resources within a short period, which will lead to emergencies of adverse impacts on society. According to the ways of pollutants following into water bodies, sudden water pollution incidents could be classified into four categories. Sudden water pollution incidents have potentially risks, and some positive approaches should be adopted to control them. Those have been discussed in the research that three sudden water pollution incidents having taken place in Huanggang River basin and their treatment measures, and the four hidden pollution hazards existing in Huanggang river basin have been analyzed.