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The effects of deformation degree and thermal aging on the tensile properties,phase boundaries,local strain distribution,coincidence site lattice(CSL) boundaries and orientation distribution of duplex stainless steels were investigated by electron backscattered diffraction(EBSD). It is found that after thermal aging,the strength of duplex stainless steels enhances and the ductility decreases. The number and density of small-angle boundaries in ferrite grains increase slightly under large deformation conditions.The plastic deformation ability and local strain in ferrite phases of the thermal aged materials decline. Large deformation destroys the original distribution of austenite and ferrite grains,as well as Σ3 twinning boundaries.

The influences of stress ratio, single overload and high-low loading sequence on the fatigue crack growth of Z3CN20-09M cast austenitic stainless steels were studied with compact tension specimens. When the stress intensity factor range is identical, the fatigue crack growth rate increases with the increase of stress ratio. During single overload, the fatigue crack growth rate shows a short period of acceleration followed by a significant decrease, leading to subsequent crack growth retardation. Similarly, high-low loading sequence with the maximum load in the second step lower than that in the first loading step results in significant crack growth retardation in the second loading step. A two-parameter model and Wheeler's model are found to predict well the crack growth behavior under constant-amplitude loading and variable-amplitude loading, respectively.

Under hatchery conditions (temperature, 23.5-24.0 degrees C; salinity, 29.5-30.0), effects of microalgal diets on growth and survival of the juvenile ark shell, Scapharca broughtonii, were investigated for 24 days by feeding with diets made of single or combinatory use of four different microalgae, Isochrysis galbana, Chlorella sp., Chaetoceros muelleri and Nitzschia closterium. The results showed that the survival rates were over 95% in all diet groups with no significant difference among them. When feeding with single microalgae, the best feeding effects on growth were observed in I. galbana, while the worst effects occurred in Chlorella sp. When feeding with various combinations of microalgae, the optimal effects on shell length and specific growth rate were observed in diets containing I. galbana compared to the other diets. The diet composed of I. galbana and Chlorella sp. (1:1) provided the best effects for S. broughtonii juveniles, resulting in a specific growth rate of 5.6% x d(-1) in shell length and 6.4% x d(-1) in shell height. These results should be valuable to direct the technique optimization of artificial breeding for the hatchery production of S. broughtonii seeds.

A strain sensor composed of carbon nanotubes with Raman spectroscopy can achieve measurement of the three in-plane strain components in microscale. Based on previous work on the mathematic model of carbon nanotube strain sensors, this paper presents a detailed study on the optimization, diversification, and standardization of a CNT strain sensor from the viewpoint of metrology. A new miniaccessory for polarization control is designed, and two different preparing methods for CNT films as sensing media are introduced to provide diversified choices for applications. Then, the standard procedure of creating CNT strain sensors is proposed. Application experiments confirmed the effectiveness of the above improvement, which is helpful in developing this method for convenient metrology.

The present paper studied the methodology of carbon nanotube (CNT) sensor applicable for the strain measurement in microscale. Based on the varieties of polarization configurations of the Raman spectrometers, a series of analytic expressions of CNT sensor were derived by applying the Raman properties of the CNT, such as the strain sensitivity and the polarization selectivity. From the viewpoint of metrology, the sensoring relationships corresponding to different polarization configurations were compared and contrasted with one another, which educed that the "bipolar homology" type is most suitable for the strain measurement where both the incident and scattered lights are continuously controllable and always remain parallel to each other. A new easy-realized control method for this configuration is introduced. The experiments proved that the method presented in this paper can effectively measure the in-plane strain components in microscale by polarized micro-Raman spectroscopy.