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Based on the SHPB (Split Hopkinson Pressure Bar), the dynamic mechanical properties of the granite in the borehole have been tested separately. The data shows that the impact dynamic strength increases as the precompression stress increases and can reach its maximum when the precompression stress is about 50% of the static tension strength. Meanwhile, the coupled static and dynamic strength increases as well, and it could reach about three times of the static precompression stress and one and half times of the dynamic strength respectively. Also, the failure model of the coupled static and dynamic loading is tension failure, which is the same as the static tension and conventional dynamic loading test.

The concentrations and fractionation of 14 rare earth elements (REEs) such as La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu in filtered water, suspended particles and surface sediments at 10 sampling sites from Gansu, Ningxia and Inner Mongolia sections of the Yellow River of China were studied by HR-ICP-MS. The results demonstrated that the total concentrations of REEs (REEs) in filtered water varied from 0.017 to 0.079 μg/L and had high concentration at S3 (0.079), S1 (0.070) and S4 (0.063) in Inner Mongolia section, while in suspended particles and surface sediments, the ranges were 148.9-246.8 mg/kg (mean 176.4) and 109.9-252.0 mg/kg (mean 179.9), respectively, and showed high concentration at S9 (246.8), S7 (252.0), S8 (229.8) in Baiyin (Gansu section) and S1 (209.5) in Baotou (Inner Mongolia section). The ratios of L/H, δEu and δCe in suspended particles and surface sediments implied light-REEs enrichment in the water compared with the background value of Chinese soil. And the chondrite-normalized REEs patterns of the suspended particles and surface sediments also showed light REEs enrichment at S1, S7, S8 and S9. The high concentrations of REEs in the Yellow River were probably due to the weathering of soil and anthropogenic activities near the river.

Only the basic wall thickness of drum is taken under consideration in traditional parallel grooved drum strength analysis, which is quite conservative for ignoring the thickness of the groove. So in this paper, it is aimed at comparing the strength simulation results for two drum models with and without the thickness of the groove and analyzing the stress distribution of the drum structure, which provides reference for the structure design and optimization of the drum.

As the monotonic decreasing data the traditional grey model is characteristic with low accuracy, using reciprocal generating operation, making full use of the new information, optimizing the background values, the formula of the parameters was induced and the grey new information GRM(1,1) model was established based on reciprocal accumulating and background value optimization. It provides a new way for the grey model. The examples show the new information model has high accuracy than the non-new information model.

The parallel grooved multi-layer winding drum can wind rapidly and reliably compared to traditional multi-layer winding drum, because of the special groove which is generated by circular and helical motion. The present paper represented the key winding stage for parallel grooved drum was the helical motion in first circle on the second layer, and the stage was simulated in ADAMS under several factors as fleet angle, winding linear velocity and rope tension. Taguchi method was adopted to estimate the winding performance through two simulation outputs, including the time delay compared to ideal time and the sum of amplitude error during the delayed time. Experiment was applied by considering more factors than that in ADAMS, and the experiment results could verify the validity of simulation in ADAMS. The simulation and experiment results showed that the optimal winding performance could be obtained with certain combination of factors.

The optimization design about hybrid discrete variables synthesizing integer, discrete and continuous variables is very significant but also difficult in engineering, mathematics for programming and operational research. Aimed at shortages of existing optimum methods, in this paper, Evolutionary Cellar Automata Algorithm (ECAA) is proposed to complex optimization problem with hybrid discrete variables which has a digging operator and two learning operators (dual arithmetic crossover operator and chaos-peak-jumping operator). The computing examples of mechanical optimization design show that this algorithm has no special requirements on the characteristics of optimal designing problems, it has a fairly good universal adaptability and a reliable operation of program with a strong ability of overall convergence and high efficiency.

Organic precursor of EP/PU was prepared by epoxy resin which was polyurethane toughened, and then modified epoxy resin adhesive was synthesized using nano-silica as modifier. Microstructure of composite materials was observed by scanning electron microscopy (SEM), the results showed that the inorganic phase had good compatibility in polymer matrix, and polyurethane in epoxy resin have formed the "island structure". The mechanical properties, thermal stability and dielectric loss, dielectric constant of composites were investigated. The results indicated that doping of appropriate amount of nano-silica could improve mechanical property, shear strength and impact strength of 2wt% SiO2/EP-PU were increased 173% and 106.67%, than that of pre-doping of composite, respectively. Thermal decomposition temperature (Td) was increased, Tdof 2wt%SiO2/EP-PU was increased 8.1°C than that of pre-doped of material. Dielectric constant (ε) was as follows: was decreased with the increase of frequency, but increased with the increase of inorganic component, dielectric loss (tanδ) was increased with the increase of frequency and inorganic doping.