Advanced Materials Research Vol. 625

Abstract: In this paper, we derive the dynamics of a spherical rolling robot, called BYQ-III, rolling without slipping on an inclined plane through the constrained Lagrange method. We present a state space realization of this constrained system, and develop a control algorithm for stabilizing the robot to track a desired trajectory on the inclined plane based on input-output feedback linearization. The validity of the proposed control scheme is then verified through simulation study.

Abstract: In this article, we research on the flip device of steel cutting machine, doing kinematics analysis to the discharging mechanism, calculating the operating parameters of the mechanism and optimizing the operating parameters of the flip device. With the using of three-dimensional modeling software UG NX7.5, reinforced flip device is precisely modeled, and all parts it concluded are assembled together, then whole mechanism kinematical simulation is carried out. The optimum flip angle of the unloading mechanism is obtained through the study of the Simulation results. By analyzing the displacements, velocity, acceleration and other data of unloading rack at any moment in the working process, the optimized design of discharging mechanism is given. Finally, the stability of discharging mechanism is analyzed.

Abstract: In this paper, the multifunctional structure was designed in electronic equipment of the control system, reducing the weight in the housings of the electronic equipment, wire and cable. The functions of thermal design and dynamic design and protection design were completed by using structure. The qualitative analysis of the center control unit structure model was done. Thermal analysis and the thermal design of the multifunctional electronic equipment structure were finished on the basis of the thermal design principles and attention of the matters. The cooling capacity was increased by fin structure with the cold plate. The modeling analyses of the same multi- functional structure with different fin spacing and height were completed in Icepak. The curves of the maximum temperature for the multi-functional structures corresponding to a group of fin height were got. The high-power MCM chip was placed in the middle of the multifunctional structure, and the remaining low-power chips were distributed around, which can reduce the thermal coupling of the chip, reducing the overall temperature of the multi-functional structure effectively, which has certain theoretical significance to the design of today’s electronic devices.

Abstract: Lubricating oil transfer pump is important functional subsystem in two-screw pump system, and all moving parts works very fast, it is easy to generate heat, that not only affect the lubricating oil transfer pump’s temperature field, but also make transmission failure by the thermal deformation which caused by high temperature of parts in contact. This paper established a finite element thermal analysis model and boundary conditions of lubricating oil transfer pump, and calculated the temperature field and thermal deformation for it during the process of oil extraction in different coefficient of convective heat transfer, analysis the change rule of the steady state temperature field and thermal deformation, proved that lubricating oil transfer pump can normal work in certain conditions.

Abstract: As one of the most important technology of Lightweight of Automobile, Self-pierce riveting (SPR) is suitable for joining similar or dissimilar sheet materials. In this paper, the process of the SPR was introduced, the test specimen was prepared by using electrolysis and anodized coated, and the microstructure of the joint is observed by the differential interference contrast method (DIC). According to the distribution of the grain size, the section of the joint could be divided into five areas, un-deformed matrix, upper plate self-locking area, lower plate self-locking area, upper plate transition area, and lower plate transition area. From transition area to matrix the grain deformation and hardness decreases gradually, and the maximum hardness of the joint was founded in the upper plate self-locking area.

Abstract: Nine types of active carbon materials’ adsorption isotherm of nitrogen at 77K were measured, and their surface texture parameters were calculated out. Then there adsorption isotherm of coal mine methane at 298K, 308K and 318K were measured experimentally. The equilibrium selectivity factor of methane to nitrogen was calculated out based on Langmuir equation. And the optimal adsorbent for coal mine methane separation is AC1 in these nine types of active carbon with separation factor of 4.6 at 298K. The experimental result indicated that the separation characteristic for coal mine methane does not only depend by its specific surface area, pore volume and it also depend by its micropore structure. The relationship between the surface texture parameters and separation factor at 298K could express by a multiple linear regression equation:α=3.20323-0.000728164S-3.73458V+8.16711V’ +0.02026d_p (R²=0.933).

Abstract: Silver doped 0.61PbMg_0.28Nb_0.67Zr_0.52O₃-0.39PbTiO₃ relaxor ferroelectrics are prepared by solid state reaction and their electrocaloric behaviors at room temperature are characterized. When the content of silver is around 0.2 wt%, the electro-caloric effect and adiabatic temperature changes are the highest. The results show that heat exchanges related to electro-caloric energy conversion and adiabatic temperature changes increase with increasing polarization of these ferroelectric ceramics. The ceramics are found to be very promising in energy conversion and materials engineering applications.

Abstract: The photophysical behavior of rhenium (I) complex having a bipyridine ligand with triphenylamidine moiety is investigated using density functional theory (DFT) and time-dependent density functional theory (TDDFT). The complex shows the maximum absorption band at 417.1 nm, with ligand-to-ligand charge transfer (LLCT) character. The lowest lying triplet excited state was localized on ³LLCT/ILCT state

Abstract: This paper selects the LiNi0.5Mn0.5O2 with layer structure as the research object, and does the future research about preparation methods and synthesis conditions. LiNi0.5Mn0.5O2 cathode material was successfully synthesized by co-precipitation method. In order to explore the optimal path of LiNi0.5Mn0.5O2 material synthesized by co-precipitation method optimal path, pretreatment, calcining heat, calcining time, cooling way on the material structure. Finally find the better synthesis conditions and improve synthesis technology.

Abstract: In order to analyze the relation between wood surface roughness of plantation- Magnoliaceae glanca Blume and sanding parameters, an orthogonal test and a single factor test were performed. The results show that the mesh of the sandpaper has remarkable influence on wood surface roughness of plantation-Magnoliaceae glanca Blumes, but the feeding speed and sanding thickness don’t; when the mesh of the sandpaper is 150, the feeding speed is 6m/min and sanding thickness is 0.6 mm during the first sanding and the mesh of the sandpaper is 320, the feeding speed is 9m/min and sanding thickness is 0.2mm during the second sanding, the smallest roughness (Ra) was obtained as 2.45μm. In the theory optimization scheme, changing feeding speed into 9 m/min with considering production efficiency and changing the mesh of the sandpaper into 240 with reducing consumption of the sandpaper, then engineering optimization scheme was obtained, and the wood surface roughness (Ra) is 2.70μm.