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A rolled and recrystallized commercially pure Zr sheet was β-solution treated and then cooled at two rates, i.e. air cooling (AC) and furnace cooling (FC). Microstructures and textures of original and β-cooled specimens were characterized by use of electron channeling contrast imaging, electron backscatter diffraction and X-ray diffraction techniques. Results reveal a novel phenomenon, i.e. the concurrent inheritance of microstructure and texture in the FC specimen cooled at a very slow rate. In contrast, for the AC specimen with faster cooling, typical lamellar α phases are obtained with relatively scattered texture. Based on comparatively crystallographic and thermodynamic analyses, reasons accounting for microstructure and texture differences in both cases are discussed, highlighting the significant role played by the variant selection behavior. It is postulated that increasing cooling rates should be more feasible to change the transformed texture in Zr materials.

In this paper, specimens cut from a fully recrystallized Zr702 sheet were surface-treated by pulsed laser at two different powers (200 and 50 W) and their microstructures were investigated by electron channeling contrast imaging and electron backscatter diffraction techniques. For both the laser-treated specimens, three modified zones with distinctly different microstructural features are presented from the surface to the substrate: melting zone (MZ), solid state phase transformation zone (SSPTZ) and essentially unaffected base metal zone. The MZ is completely comprised of α plates while the SSPTZ could be further divided into the SSPTZ-1 and the SSPTZ-2, according to cooling mainly from β and α + β domains, respectively. With decreasing the laser power, the modification depth and the mean width of α plates decrease. Detailed characterization on microstructural features suggests that the plate structures (MZ and SSPTZ-1) in the 200 W and the 50 W specimens are produced by diffusion and diffusionless transformation, respectively. For those untransformed α grains in the SSPTZ-2 of both specimens, in spite of maintained bulk morphologies, slight subdivisions by subgrains are found inside them due to extensive dislocation activities induced by transformation stresses and/or their recovery.

In this work, the surface of a fully recrystallized Zr702 is treated by pulsed laser following which microstructural changes are investigated by use of electron backscatter diffraction and electron channeling contrast imaging techniques. The pulsed laser treatment results in three distinctly different microstructural features from the surface to the substrate: fine α plates with a few hundred nanometers in width (zone I), irregular-shaped grains with varied sizes (zone II), and essentially unchanged equiaxed grains (zone III). The α plates result from rapid phase transformation due to easy heat extraction of the pulsed laser with dense nanoscale twins inside those plates closer to the surface. The origin of the irregular-shaped grains is found to be related to insufficient recrystallization of antecedently formed α plates near the substrate. Hardness tests reveal highest value (∼356.7 HV) near the surface in zone I and the lowest value (∼165.2 HV) in zone II. Reasons accounting for the difference are discussed in terms of various microstructural characteristics induced by the pulsed laser surface treatment.

A 10 1 ¯ 1 twin relationship between α plates was repeatedly reported in β-quenched Zr alloys in literature. In this paper, however, we demonstrate that the special twin relationship between α plates should be correctly identified as one of five common Burgers misorientations. The shared plane between two α plates with such a Burgers misorientation is determined to be 10 1 ¯ 1.06 . Such a clarification helps to reach more accurate understanding of boundary characteristics of β-quenched microstructure in Zr alloys.

A Cu-10Fe alloy with magnetron sputtered Al films was irradiated by high current pulsed electron beam (HCPEB) with various pulse numbers, next changes of its microstructure and corrosion property were investigated. Compared with the initial sample, microhardness and corrosion resistance of the aluminized Cu-10Fe alloys after the HCPEB treatment are remarkably improved with increasing pulse numbers. This improvement could be attributed to formation of Al2Cu intermetallic compounds, occurrence of liquid phase separation and grain refinement in the surface layer of the Cu-10Fe alloy during the process of rapid remelting and solidification induced by the HCPEB treatment.

Optimizing the NACA0015 airfoil which is widely applied in small-scale vertical axis wind turbine to make it has a better aerodynamic performance. In the optimization process, using CST parameterization method to perturb the airfoil geometry, the thickness and camber of the airfoil are selected as the constraint, and the value of the maximum tangential force coefficient is chosen as the objective function, the genetic algorithm based on non-dominated sorting (NSGA-II)is selected as an optimization method, calculates the aerodynamic performance of the airfoil by applying the approach of combining XFOIL program and Viterna-Corrigan post-stall mode ,and establishes the optimizing process by the optimization software modefrontier for NACA0015 airfoil’s muti-point optimization, validate the airfoil’s performance with CFD finally. The result illustrates that, by comparing with the NACA0015 airfoil, the optimized airfoil’s lift to drag ratio is improved over a wide range of attack angles, the stall performance is more gentle. The maximum lift coefficient, the maximum lift-drag ratio and the maximum tangential force coefficient are increased by 7.5%,9 and 8.87%, respectively. The optimized airfoil has a wide variable condition performance, more suitable for the operating conditions of a vertical axis wind turbine. Finally, predict the rotor efficiency with optimized airfoil and NACA0015 airfoil for different tip speed ratios and different solidities with multiple streamtube model, the result shows the rotor with optimized airfoil has a higher efficiency. Keyword: vertical axis wind turbine; CST parameterization; NSGA-II; airfoil; optimization; multiple streamtube model

Firstly, the related theories about agricultural science and technology innovation and project approval evaluation are combed and summarized. By combining application and finish books of science and technology support plan project in agricultural field of Ministry of Science and Technology with stronger innovation, case analysis and expert interview are conducted. Evaluation indexes of agricultural science and technology project based on innovation value are proposed initially, and there are 50 initial indexes. After that, via focus group talk, qualitative research is conducted to further adjust innovative evaluation indexes, and 50 initial indexes are deleted to 41. The importance of the 41 indexes is scored by the experts, and index screening and classification are conducted by verification factor analysis in structural equation model. It not only obtains index classification but also finds action mechanism among innovation demand, innovation mode, research thinking, treatment method of difficulty, and predicted risk. The research could straighten up ideas of project review experts in agricultural field and provide reference for applicant designing project.

This paper carries out a questionnaire survey of persons in charge of the agricultural project in the "Eleventh Five-Year National Support Program" on the level of innovation in projects and the factors influencing innovation. After the linear regression analysis of the survey data, it is found that the factors influencing the innovation in agricultural science and technology projects include the level of innovation in scientific achievements, efficiency of research methods and creation of innovation environment. Through the variance analysis of the level of innovation and its influencing factors related to different innovators, it is found that there are differences in the statistical significance of level of innovation in projects among universities, research institutes, research and extension departments directly under the government, and enterprises; there are no significant differences in the understanding of factors influencing innovation, that is, different innovators basically have the same understanding of factors influencing innovation, but the assessment on level of innovation in projects completed is different to some extent. On this basis, this paper proposes the recommendations for further strengthening the level of innovation in agricultural science and technology projects in order to provide a theoretical reference and practical basis for the project managers to effectively improve the level of agricultural science and technology project management, and enhance the level of innovation in projects.

Looking from the existing research, improving the social capital of the poverty population is an effective way to promote the population quality and the income growth of the poor people. Based on the existing research, with the rural poor households in Sichuan Liangshan as the research object, this article used factor analysis to measure social capital stock, and then analyzed the influence of social capital on the income of the poor peasant households in that region, through the reconstructed production function. The results show that the poor households’ social capital has a significant impact on their income level, and the effect degree varies in different income levels.