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Through artificial seawater simulation test this paper analyzed erosion mechanism of concrete corroded by the ions in seawater. High performance marine concrete was successful developed because of mineral admixture and corrosion-resistance additive double adding. The paper researched the durability of concrete containing freeze-thaw cycles and chloride ions diffusion. Modern testing technologies were used such as scanning electron microscopy and differential thermal analysis in the experiment. Research founded that the amount of unstable or metastable matter reduced such as calcium hydroxide and high alkaline calcium aluminates in the marine concrete. There were more compact hydration products created which made the structure stabler and denser. Those were the reasons that the marine concrete had excellent performances in terms of erosion-resistance and durability.

Similar model experiment under confining pressure, research latticed shell lining the mechanical properties and the carrying capacity of new support for the underground engineering - network shell support, according to the model experiments and theoretical. Test results prove that the the latticed shell supporting structure has good mechanical properties and a high level of support is a reliable form of support. Can make up for the deficiencies of the existing soft rock roadway structure, calculated to provide a reliable basis for mesh shell lining theoretical analysis.

Combining with a mountain highway retaining wall earth pressure measured data, carried out a detailed study of the of multiple retaining wall back soil pressure distribution law, based on multi-level retaining wall measured horizontal earth pressure data mountainous retaining wallshorizontal earth pressure formula is derived, summed up the horizontal earth pressure with filling height variation.

We have reported the environmental and economic effects of VRLA recycling methods. The possible waste water, solid and gas produced in the recycling process are fully discussed. Through proper treatments, the wastes can be emitted according to corresponding standards. And careful disposal of VRLA results not only in less environmental pollutions, energy and mineral resources consumptions, but also in considerable economic profits.

A fast, effective polar components detection device for quality evaluation of frying oil was designed. The theory of the device is based on a capacitance sensor which takes the frying oil sample as the media. A sine wave signal that generated by DDS signal generator to excite the capacitance sensor. Then the device exported a voltage value which associated with polar components of the frying oil through the signal conditioning circuit. The experimental data was compared with column chromatography, using MATLAB to solve the data fitting process, the result shows that the correlation coefficient is 0.9817, indicating that the frying oil quality detector method is simple, fast, non-destructive and no solvent.

Turbulence mixing in T-junctions filled with porous metal materials is numerical investigated using Large-eddy simulation turbulence model. Three cases of porous metal materials, made of three sintered metal spheres with different thermal conductivities (387.6 W/m۟۬•K for copper, 202.4 W/m۟۬•K for aluminum and 16.3 W/m۟۬•K for steel), are predicted. Compared the results of three cases, a higher thermal conductivity can also contribute more greatly to heat transfer enhancement. In T-junctions filled with porous metal materials, thermal conductivity is weakened considerably by the turbulence mixing of hot and cold fluid. The temperature fluctuation are no obvious different.

In order to study the compatibility between polycarboxyIn order to study the compatibility between polycarboxylates superplasticizer (PC) and different kinds of retarders, sodium citrate (SC), sodium gluconate (SG), sodium hexametaphosphate (SH) and sucrose (SU) were compounded with PC respectively in the same proportion. The liquid degree and its loss of cement paste, the setting time of cement, the blending strength and compressive strength of mortar that admixed with different kinds of retarders were measured, and the influence mechanism of the compatibility between different kinds of retarders and PC were analyzed. The experiment results showed that it was benefit to the liquid degree of cement paste after SG or SH or SU was compounded with PC; The setting time of cement could prolonged more by SH or SU; Blending and compressive strength of mortar in different ages were enhanced in large extent after SG were adopted; The strength of mortar was reduced in early age and enhanced in small extent in mid-later age after SU was compounded. Comprehensively considering to the influence of liquid degree, setting time and strength, the compatibility of SG with PC is higher than other kinds of retarders.

The velocity fields of turbulent flow in Tee junctions have been calculated using large-eddy simulations model for three cases of various inlet velocities with periodic porous media. The ratio of the inlet velocity of the main tube to that of the branch tube were respectively 0.5, 1 and 2 in three cases. In the porous medium region of the Tee junction, the velocity at the center is obvious larger than that at the top or the bottom and the pressure drop heightens rapidly. Comparison of the three cases, the pressure drop, mean velocity, normalized velocity fluctuation and the velocity oscillation versus time are increase as the inlet velocity of the main tube increase.

In order to study the effect of fly ash (FA) and slag powder (SP) on coefficient of thermal expansion (CTE) of concrete, the influence of FA and SP to CTE of concrete was compared, the influence of replacement proportion of FA to CTE of concrete was tested, and the unhydrate mineral admixture particles were observed with SEM and validate with Energy Spectrometry. The results showed that the influence of FA and SP to CTE of concrete is different, the CTE of SP concrete is near to the norm concrete，but is higher than the FA concrete; With the replacement proportion of FA increased, the CTE of concrete decreased; The per strength CTE increased obviously when the replacement proportion exceed 10%, and the decrease of strength badly when the replacement proportion of FA exceed 30%; The unhydrate mineral admixture particles is one of the most important factors that influence the CTE of concrete, and the mineral admixture could influence the composite and the microstructure of cement paste, then cause the change of porosity and density.

This work presents a motion planning approach for tomato harvesting manipulators with seven degrees of freedom (7 DOF) based on an optimization technique and alternative method. It is to find optimal joint perturbations during the path planning so that a manipulator reaches a goal from an initial position with high accuracy. The optimization model consists of the objective function defined by the tracking error and the representation of a set of mathematical relationships that describe the kinematic restrictions of the manipulator. In this method, only a forward kinematics is used and the complex mathematics in numerical solutions of an inverse kinematics is avoided to reduce the computation load. Simulation results show that the tomato harvesting manipulator can move the end-effector to the target from an initial position along a specified geometric trajectory in its workspace. Simultaneously, the joint displacements vary smoothly within their limits during tracking. The position absolute error, moving velocity and precision of the end-effector are 0.53mm, 0.18m/s and 3.75% respectively, which fulfill the requirements of tomato picking with well working efficiency.