Advanced Materials Research Vols. 479-481

Abstract: Non-magnetic steels are required in energy and transportation fields such as superconducting energy storage equipment, magnetic liquid power generation equipment, superconducting generators, superconducting power transmission and ship electromagnetic propulsion. Experimental research on steel making, hot rolling, solution and aging for non-magnetic steel 30Mn27Al4V was carried out in the laboratory. The microstructure evolution was observed and the mechanical property and relative magnetic permeability were tested after heat treatment. The effects of fine particles such as VC, VN and V(CN) dispersively distributed in austenite matrix on precipitation, grain refinement and austenitic nucleation were analyzed. The microstructure of the tested steel is austenite. The grain size is 24~28μm. At room temperature, the yield strength and tension strength are 556 MPa and 701 MPa, elongation after fracture of the steel is 47%, the yield ratio is 0.79, strength and ductility product is 32.9 GPa%. After solution and aging treatment, the steel shows a yield strength of 325~371 MPa, tension strength of 550~645 MPa, elongation of 58~78 %, a yield ratio of 0.54~0.60, strength and ductility product of 36.3~46.3 GPa%. The relative magnetic permeability is below 1.005. The results indicate that the tested steel exhibits good mechanical property and non-magnetism. It has no elements of Ni and Cr, so it just needs simple process flow and lower production cost. The numerous applications of the steel in industry can create great economic benefits.

Abstract: This article studies about anti-jamming problem for frequency control system with three experimental methods which are magnetic shielding, grounding and filtering. The results demonstrate that filtering is the most evident anti-interference. the interference of frequency converter is independent with the signal; Shielding on both ends of the grounding is better than single ended grounding. All of the conclusions will be used for reference.

Abstract: In accordance with the newly reinforcement technology of Polyvinyl Alcohol(PVA) fiber ferrocement mortar, this paper in the first place introduces the design principle and the excellent mechanical properties of the new method. Secondly, the paper summarizes the construction techniques and the points of controling in the implement process of this new technology. Finally, a comprehensive analysis of its economic advantages is presented.

Abstract: Cubic-like lead sulfide (PbS) films were in situ fabricated on lead (Pb) foil on a large scale by solvothermal method. Ethanol and ethylenediamine were used as the solvent. The films were characterized by X-ray diffraction (XRD), Scanning electron microscopy (SEM), absorption and the Fourier transformation-infrared (FT-IR) spectra. A solar cell was made by the hybrid film of P3HT and cubic-like PbS. The solar cells are photosensitive in a large spectral range (visible and near infrared regions). The cell with the area of 0.20 cm² without any special treatment has shown the values of open-circuit voltage (Voc) of 250 mV and short circuit current (Jsc) of 0.01 mA/cm² with the efficiency of 0.01 % and the fill factor (FF) is 0.36 under illumination intensity of 100 mW/cm².

Abstract: A single-span and two-story frame specimen with reinforced beam ends has been tested under low-frequency cyclic loading. Based on the test results, the failure patterns, hysteretic behaviors, energy dissipation and deformation ability were analyzed. The results showed that the failure mode of the test specimen was ductility. Plastic hinges appeared at the changing point of the beam cross section far away from the beam-column joint. Hysteretic curve of the frame was full and the whole ductility coefficient was enough higher than 4.4 under horizontal low-cyclic loading. It can be concluded that the energy dissipation and the deformation ability are both better. So the whole steel frame connected with reinforced beam ends has good seismic performance. And the requirements of anti-seismic ability can be satisfied.

Abstract: The forced convection in the blocky stone layer plays a major impact on the temperature field of embankment in Qinghai-Tibetan Plateau. Thus, a field test on air flow inside the blocky stone layer has been carried out to make clear the ventilation characteristics. The results show that pore-air velocity in embankment slope of following wide side is in well accordance with the external wind, and the temperature in sunny slope is higher than in shaded slope. The variation of velocity in sunny slope is larger than shade in summer, which is inverse in winter. The time of air flow through an embankment was calculated by the Bernoulli Equation, and the results show that the air can flow though the embankment in less than a minute, indicating the pore-air velocity in blocky stone layers is mainly influced by atmospheric wind field and blocky stone layers have good ventilation ability. So, it is advisable to consider the ventilation ability in analyzing the temperature field of block stones.

Abstract: Zirconia coating was produced on Al-Si alloys by plasma electrolytic oxidation (PEO). The alkaline electrolyte containing Zr(OH)₄ powders was used. The composition and structure of the coating were investigated by SEM and XRD. The results show that in the initial stages of oxidation the growth of coating belongs to the stage of anodic oxidation controlled by electrochemical polarization. The growth of coating is mainly outward growth and the growth rate is faster. With elongated treated time and increased thickness of the coating, the growth of coating is mainly ingrowth. In contrast with the stage of anodization, the growth rate of plasma electrolytic oxidation is slower than anodization. The coating consists of t-ZrO₂, m-ZrO₂, α-Al₂O₃ and γ-Al₂O₃.T-ZrO₂ is the main phase and distributes in outer layer of the coating, however, α-Al₂O₃ appears in inner layer of the coating. Many micro-particles appear on the coating surface with dimension of 1-2μm.. In the process of plasma electrolytic oxidation, Zr(OH)₄ powders move and deposit on the mouth of plasma discharge channel under the effect of electric field force, then it is transformed to ZrO₂ by the high temperature of plasma discharge.

Abstract: It is important to conduct a regular study on the status and the needs of the users’ demand， along with the development of Xinjiang electronic government (E-government). Literature reviews show that researches on Chinese E-government tend to focus on the technical aspects. However, there is little research focused on the E-government users, especially of Xinjiang. This article provides a better scope of knowledge on the Xinjiang E-government users and their demand to use and benefit from E-government information and services.

Abstract: The paper analyze the existing CAD / CAE methods and differences in product design requirements. It points out that firstly, performance analysis and design is the core of mechanical product design; Secondly, integrated CAD / CAE technology, product design should be based on CAE-centric the design process. It proposes simulation-based design methods and constructs a performance-oriented product design system.

Abstract: Cable is widely used in the actual project of prestressed steel structure for its mechanical properties can be fully used. Saddle-shaped cable net is a new type of large-span prestressed structure, but there is little study on the impact of different cable types on the mechanical properties of saddle-shaped cable net during the construction. In order to meet the thought of integration of design and construction, a finite element model of saddle-shaped cable net has been established. The four types of cables such as semi-parallel steel tendon cable, steel wire rope cable, steel strand cable and full-locked coil rope are chosen. The impact on mechanical properties of the structure was analyzed by different cable types.