Research on the influence of design parameters on mechanical performance of net arch bridge

In order to study the suspender layout parameters and design parameters of the tied arch bridge with mesh suspenders under the action of vehicle load, the structure stress is more reasonable and meets the higher economy and aesthetics. Taking a 96m span reticulated tied arch bridge as the engineering background, the finite element model is established by using Midas/Civil 2019 program. The variation law of internal force and Suspender Force of the structure is calculated and analysed under the change of rise span ratio and suspender number parameters, and the relatively optimal value range of corresponding parameters is given. The results show that the rise span ratio should be 0.2-0.24; The number of Suspenders for one side arch rib should be 34-38; The relatively optimal range of the above parameters is discussed for reference.

Experimental Study on Removal of NO Using H2O2/UV System

In this paper, use homemade experimental platform to experimental study on removal of NO using H2O2/UV system. The factors include concentration of H2O2, initial concentration of NO, concentration of O2, temperature of H2O2solution, concentration of a metalic catalyst, gas flow. Carrying on orthogonal test with the above 6 factors, determining the optimal value range of the various influencing factors and the optimal technical conditions are determined. When concentration of H2O2is 8%, concentration of O2is 5%, gas flow is 850ml/min, initial concentration of NO is 650mg/m3, temperature of H2O2solution is 55°C, the mole ratio of Fe2+is 1:300, then the NO removal is 88.6%. Based on this discussion and analysis, the H2O2/UV system of NO Removal system has certain technical popularization.

Effect of Ball Material Ratio on the Grinding Efficiency of Copper-Bearing Minerals in Dahongshan

In this paper, The Copper-bearing minerals Powder (≤2mm) in Dahongshan is used in conical ball grinding, the experimental study shows that the effect of ball material ratio on the grinding efficiency is obvious. The critical value and the optimal value range of the ball material ratio are different on different grinding stages, the feasible ball material ratio of coarse grinding is bigger than the one of fine grinding. In the test conditions, in terms of the ball material ratio, the critical value of ores’ over crushing in coarse grinding is 13, and the optimal range is 6-8, which is beneficial to the next beneficiation; while the critical value in fine grinding is 7 and the optimal range is 5-7. Although the ball material ratios are different, the change rule of grinding fineness corresponding to different particle size fractions is consistent, which can be used as a reference in the site operation optimization.