Abstract: The friction and abrasion of the cylinder and piston ring of the vehicle diesel has been carried on experimentation research using oil analysis technology in order to improve the diesel running-in quality and shorten the diesel running-in time, and analyze the defferent lubrication oil and surface roughness of the diesel piston ring in order to find a way to reducing abrasion of them. The experiment proves that the machining precision of the piston ring will affect evidently the oil film formed of between the piston ring and cylinder. The critical load forming oil film is inverse ratio Ra of the piston ring. It has been proved that it is a effective method to monitor the friction and abrasion of diesel piston ring.
Abstract: Aiming at Temperature and Humidity Control for the Weaving Workshop, a Remote Temperature and Humidity Monitoring System Based on Wireless Sensor Network Is Designed. with Using Industry-Standard ZigBee Protocol Network, the Monitoring System Is Composed of Wireless Sensor Network Nodes and Central Node Based on CC2430, and the LabVIEW Virtual Instrument Development Platform Management as Nodes of the Host Computer. Practice Shows that the Monitoring and Control System Is Simple, Reliable, Low Power Consumption, Low Cost Communication Etc.
Abstract: Fuzzy system is known to predict model in the electrodialysis process. This paper aimed to predict separation percent(SP) of NaCl solution as a function of concentration, temperature, flow rate and voltage. Besides, in the MATLAB, ANFIS(Adaptive Neuro-Fuzzy Inference System) based on Sugeno fuzzy model, its structure was similar to neural network and could generate fuzzy rules automatically. We obtained fitted values of SP by ANFIS. Then, we studied these influencing factors on fitted values of SP. Finally, we draw a conclusion that SP is in direct proportion to temperature and voltage, but in inverse proportion to concentration and flow rate.
Abstract: Fuzzy system is known to predict model in the electrodialysis process. This paper aimed to study fitting effect by ANFIS in a laboratory scale ED cell. Separation percent of NaCl solution is mainly as a function of concentration, temperature, flow rate and voltage. Besides, ANFIS(Adaptive Neuro-Fuzzy Inference System) based on Sugeno fuzzy model, its structure was similar to neural network and could generate fuzzy rules automatically, using the error back propagation algorithm and least square method to adjust the parameters of fuzzy inference system. We obtained fitted values of separation percent by ANFIS. Separation percent from experiments compared with the fitted values of separation percent. The result is shown that the correlation coefficient is 0.988. Therefore, it is verified as a good performance in the electrodialysis process.
Abstract: The study of calcium carbonate adsorption is important significance to understand the fouling mechanism that is a major component of heat exchanger fouling. The influence on the adsorption of CaCO3 crystallization fouling was researched in different material, roughness and supersaturation by the electrochemical impedance-time method. The results show that the material is not the essential influence on CaCO3 absorption by analyzing the CaCO3 adsorption layer data. The optimum conditions of maximum adsorption CaCO3 quality: the roughness of the electrode polished by the sandpaper of 360 mesh, the supersaturation of 0.291g / L CaCO3 solution. The experimental results of supersaturation are concordant with the roughness experiments. When the supersaturation is the middle value, the maximum adhesive force can reach the maximum. So the regulation of calcium carbonate supersaturation and roughness of heattransfer equipment can prevent the fouling. This study is a powerful detecting method to research the influence of the roughness on the adsorption of CaCO3 crystallization fouling.
Abstract: A Realizable k-ε turbulence model in conjunction with a standard wall function has been applied to the prediction of a fully-developed two-dimensional jet impinging within a semi-confined space. A single geometry with a Reynolds number of 10,000 and a nozzle –to-plate spacing of eight diameters has been considered at different inlet boundary conditions. The numerical results, including the time-averaged velocities and the turbulent intensity, have been compared with the experimental data reported by Yoshida (ref 5). It is found that the trends in the axial velocity, the radial velocity and the turbulent intensity are fairly predicted. The fully-developed boundary condition is generally better than the constant velocity boundary condition. The differences between the numerical and experimental results can be attributed to the turbulence model and the treatment of the low Reynolds number zone near the wall.
Abstract: The mercury concentration in the coals from Datong and Xiaoyi, Shanxi has been measured to study the relationship between mercury enrichment in coal and coalseam depth. Ten samples were researched, of which 7 coal and rock samples from the main coalseam and the places around it were collected at a miner in Datong city, and 3 coal samples from three coalseams at a miner in Xiaoyi city. The mercury concentration in the coal and rock samples was measured with US EPA Method7471, which is a standard method recommended by the US EPA. The results show that the mercury enrichment in coal is higher than that in rock in the same conditions, and the mercury concentration in the longer-buried coal is higher than that of the shorter-buried. However, the mercury concentration in coal with depth has no definite linear correlation, varying in different coal fields.
Abstract: Mn, Fe doped ZnO powders (Zn0.95-xMnxFe0.05O2, x≤0.05) were synthesized by an ameliorated sol-gel method, using Zn(CH3COO)2, Mn(CH3COO)2 and FeCl2 as the raw materials, with the addition of vitamin C as a kind of chemical reducer. The resulting powder was subsequently compacted under pressure of 10 MPa at the temperature of 873K in vacuum. The crystal structure and magnetic properties of Zn0.95-xMnxFe0.05O2 powder and bulk samples have been investigated by X-ray diffraction (XRD) and vibrating sample magnetometer (VSM). X-ray photoelectron spectroscopy (XPS) was used to study chemical valence of manganese, iron and zinc in the samples. The x-ray diffraction (XRD) results showed that Zn0.95-xMnxFe0.05O (x≤0.05) samples were single phase with the ZnO-like wurtzite structure. No secondary phase was found in the XRD spectrum. X-ray photoelectron spectroscopy (XPS) showed that Fe and Mn existed in Zn0.95-xMnxFe0.05O2 samples in Fe2+ and Mn2+ states. The results of VSM experiment proved the room temperature ferromagnetic properties (RTFP) of Mn, Fe co-doped ZnO samples.
Abstract: In basic sheet metal forming process such as cylindrical deep drawing, bulging, hole flanging (or reaming), etc., deformations in-plane can be considered as changes of the curvature of different microrings. The deformation of each microring is equivalent to a bending process of plate with small width. The differential balance equation of the deformation region can be expressed as simple form of unification. The deformations in the symmetry plane of the sheet metal are part of bending and reverse bending, so the bending analysis method can be used to analyze operation. Some results were obtained by the bending analysis method.
Abstract: Multi-function self-help climbing stair wheelchair, which based on transforming the traditional wheelchair, achieves the function of climbing stairs by adding some simple structure. This article will introduce the wheelchair structure and principle and research and analysis the feasibility analysis.