Time filter

Source Type

Zhou X.,Xian Polytechnical University | Zhao Q.,Xian Physical Education University
Applied Mechanics and Materials | Year: 2012

In the background of Digitized Industrial Design drived by web evaluation Strategic which based on web become an important stage of promoting the design qualities. From the theory of evaluation the Multi-Target web evaluation system was structrued which based on ASP technology and fuzzy evaluation theory. This new evaluation strategy will improve the application area of evaluation strategic. Provided a rational objective method for designers and producers to select and provided the basis of further research on design theory and practice. © (2012) Trans Tech Publications, Switzerland. Source

Shui L.-Q.,Northwestern Polytechnical University | Liu Y.-S.,Northwestern Polytechnical University | Gu Z.-P.,Xian Polytechnical University | Yue Z.-F.,Northwestern Polytechnical University
Zhendong yu Chongji/Journal of Vibration and Shock | Year: 2012

Using classical equations of fluid-structure interaction (FSI), the influence of axial external periodic excitation on the stability of a transverse vibration of a pinned-pinned pipe conveying pulsing fluid was studied. The second-order Galerkin method was used to solve the equations. The convergence of the solutions was taken as a stability criterion to obtain a stability curve. The results showed that the axial periodic excitation can improve the stability of the pinned-pinned pipe conveying pulsing fluid when the excitation has one of the instable frequencies of the pipe, and the amplitude of the excitation is in a certain limit; the stability of the system began to deteriorate when the amplitude of the excitation exceeds the certain limit; the excitation can not produce significant effect on the stability of the pipeline when the frequency of the axial periodic excitation is far away from the instable frequencies of the pipe. Source

Wang P.,Xian Polytechnical University | Hu R.,Xian Polytechnical University | Zhong H.,Xian Polytechnical University | Li J.,Xian Polytechnical University | Zhao J.,Control Iron and Steel Research Institute, China
Tezhong Zhuzao Ji Youse Hejin/Special Casting and Nonferrous Alloys | Year: 2012

The flow field, temperature field and microstructure of complex thin-walled superalloy K4202 castings were simulated with the help of the finite element software. The results show that, with a well established filling system, the thin-walled castings can be well filled in the condition of low super-heating. According to the temperature field, the shrinkage porosity easily occurs in the thick wall location or the location with variable cross-sections. With the low super-heating pouring, the uniform structure with the grain size ASTM2-3 can be observed in the whole castings. Source

Wang C.,Xian Polytechnical University | Li Y.,Xian Polytechnical University | Zhao H.,Xian Polytechnical University
ICAFPM 2011 - Proceedings of 2011 International Conference on Advanced Fibers and Polymer Materials | Year: 2011

O-carboxymethyl chitosan (OCMC) was synthesized by ultrasonic irradiation with chitosan and chloroacetic acid in NaOH-ethanol. The degree of substitution (DS) of carboxymethyl and amino retained amount (NH2%) were studied under the orthogonal experiments of four factors at three different levels and the reaction condition was optimized. Then quaternary ammonium group was introduced by the reaction of preferable OCMC with glycidyl trimethylammonium (GTA) in ethanol. The DS of the quaternization group was studied. Antimicrobial activities of quaternized O-carboxymethyl chitosan (QOCMC) were evaluated against Escherichia coli and Staphylococcus aureus. The structures of the derivatives were characterized by the FTIR spectrometer. Experiment results validated that QOCMC is better than OCMC in the properties of antimicrobial activity. Source

Zhang Y.,Xian Polytechnical University | Kou H.,Xian Polytechnical University | Li P.,Xian Polytechnical University | Zhong H.,Xian Polytechnical University | And 3 more authors.
Tezhong Zhuzao Ji Youse Hejin/Special Casting and Nonferrous Alloys | Year: 2012

Through establishing a three-dimensional axisymmetric finite-element model, the temperature distribution of TC4 alloy ingot during VAR (vacuum arc remelting) process was simulated by moving boundary heat transfer method. The solidification structure and shrinkage porosity (hole) formation in the TC4 alloy ingot during VAR process were visualized by the coupled method of cellular automaton (CA) and finite element (FE) method. The simulated results are well in agreement with experimental ones in grain structure, growth direction of columnar crystal, transformation of columnar grain into equiaxed grain as well as shrinkage porosity (hole). Source

Discover hidden collaborations