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A dielectric resonator antenna with special shape for camouflage in the city is proposed in this paper. A series of antennas with different materials and shapes chosen from the normal building were made and analyzed. It was found that electrical properties of the antennas were extremely affected by shapes of the antenna and locations of the tap. Based on the results, a dielectric resonator antenna with return loss >-20dB, peak gain >6 dBi at 1.275 GHz was demonstrated. This technique will allow the design and installation of dielectric resonator antenna with good electrical properties for camouflage in the city .

The first degree second order moment method (JC method) is applied to analyze the reliability of recycled aggregate concrete-filled steel tube (RACFST). Several performances are studies, which are the influences of different load combinations, specific values of loads,confinement coefficients and recycled coarse aggregate replacement percentage on the reliability of the column. It is found that the reliability index varied with the load combination and specific value of loads. The analytical results indicate that the reliability index of the round steel tube is higher than square steel tube and the influence of recycled coarse aggregate replacement percentage can almost be ignored It can be concluded that the formula had great influence on reliability index and the revised formula can meet the requirements of the ductility of structure reliability.

By using the simple stiffness matrix formula of reinforced concrete (RC) cross-section under bending and compression, some RC cross-sections under bending and compression were traced through full path. Based on the numerical analysis, the damage of each point was calculated in a cross section, and the damage distribution of one member under the ultimate load was analyzed. This was agreement with experimental phenomena. In cross-section level, cross-section whole damage index was given and researched; and it could well explain cross-section mechanical behaviors.

Based on micro structure of Ni-based single crystal superalloy, a γ/γ’ two-phase unit cell finite element model was established, and its cyclic stress-strain was simulated under tension/torsion cyclic loading. A low cycle fatigue (LCF) life prediction model of single crystal superalloy was proposed by using cyclic plasticity strain energy as a parameter based on energy dissipation theory. Calculation results of macro finite element model and γ/γ’ two-phase unit cell micro finite element model, and multiaxial LCF test data of CMSX-2 Ni-based single crystal superalloy along [001] orientation were applied to fit the LCF life model by multiple linear regression. The results show that the unit cell model not only reflects the microstructure characteristics of single crystal Ni-based superalloy, but also is better than the macro model in accuracy of analysis, and greatly improve the accuracy of fatigue life prediction. Almost test data fall into the factor of 2.0 scatter band.

The electrochemical behaviors and sensing application of 100nm-gold plate electrode based on 6-amino-1-hexanethiol (6-AHT) self-assembled monolayer (SAM) have been investigated in this paper. The 6-AHT assembled nano gold plate electrode exhibited a nice linear potential performance of responding to Hg2+ in the range of 1.0×10-8—1.0×10-6 mol/L with a slope of 42.57 mV/-pC (25°C) in Tris-HCl buffer solution (pH=5.0). No obvious interferences were observed from Na+, K+, Ba2+, Mg2+, Ca2+, and Cr3+. The detection limit can be evaluated to 8.0×10-9 mol/L. In addition, the electrode possessed good stability and reproducibility with a recovery rate of 96.50-103.67%, indicating that it can be used for the determination of Hg2+ content in environmental waste water samples. The sensing mechanism of 6-AHT monolayer has also been discussed by the formation of coordination structure between amino groups of the thiol molecules and the mercury ions.