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Precision machining of thin-walled complex components has been a serious challenge, and the machining errors are mainly due to cutting force which can induce tool-workpiece deformation and chatter vibration phenomenon. Based on the principle of stiffness optimization and material removal sequence optimization, rigidity of thin-walled component is greatly improved with non-uniform allowance distribution and spiral milling process techniques.

In allusion to the management characteristics of the cement laboratory samples, this paper conducts introduction and comparative analysis on such four kinds of identification as inspection organization, traditional cement sample identification of corporate laboratory, paper-electronic tags and wireless monitoring devices. It shows that wireless monitoring devices are superior to the traditional sample identification and paper-electronic tags, and can achieve intelligent management of cement samples ensuring objective and fair inspection data.

Nano-sized nitrogen-doped Ti-W mixed oxides (N-TiO2-x%WO3) were prepared by soft chemical method, and their intrinsic characteristics were investigated using XRD, TEM, N2 adsorption and desorption isotherms, UV-Vis diffuse reflectance spectra and XPS. Experiments on photodegradation of Methylene Blue (MB) under visible light irradiation were carried out to evaluate the photocatalytic abilities of N-TiO2-x%WO3. Chemical Oxygen Demand (COD) analysis was also performed to evaluate the mineralization abilities of N-TiO2-x%WO3. It is shown that the N-TiO2-x%WO3 exhibited higher COD removing rates compared with Degussa P25. The color bleaching rates of N-TiO2-x%WO3 were equal to that of Degussa P25. The enhanced photocatalytic activities were probably related to the strong absorption abilities of the N-TiO2-x%WO3.

The finite element analysis was carried out on the piston of WWD - 0.8/10 type air compressor under the action of mechanical load stress and deformation.Using three-dimensional modeling software Solidworks to establish a simplified geometric model of piston in air compressor ,Transform the model built in the three dimensional finite element analysis software into the finite element model for analysis,Determine the method of the piston by the mechanical load and boundary conditions,Completed the stress analysis and deformation analysis of the piston under the mechanical load ,The results of analysis of the piston design optimization has important reference value.

Based on the side hole and no flange and one-step drawing part forming analysis and comparison of the process, the compound die that can complete 4 procedures -blanking, drawing , punching and trimming at in the same forming-position was synchronously designed. Production testing confirmed that there were different levels of improvements in the product quality, production efficiency and economic efficiency. This paper describes die structure, die working process, design and manufacture of main pans of die.

Error analysis of measuring instruments is a significant part in the process of measuring instruments design with which primary error factors influencing measuring accuracy can be obtained. In order to correctly analyze and evaluate the sensors errors, the influence on final measurement result caused by error factors of all parts should be taken into account. Electric error consist zero voltage error and power errors including amplitude errors, phase errors and frequency errors. It will be difficult and cost much to improve accuracy of measurement with hardware method. So error correction technology is employed to ensure system accuracy. This method not only improves accuracy effectively but also reduces manufacturing cost of measuring instruments. In addition, errors suppression technology based on error separation, error correction of the Ordinary Least Square (OLS) and negative feedback model is proposed. Improving Time­-grating displacement sensor’s measurement accuracy plays an important role in the mass production of Time-grating displacement sensor.

With the increasingly competitive pressure, spunbond nonwoven products marketed is becoming more cost sensitive. Inorganic additives, which is mainly composed of calcium carbonate , has been mixed into the standard organic spinning solution for either reducing the raw material cost or enhancing some of the physical properties. Therefore, its necessary to find a test method to evaluating the quality of these products. This paper developed a test method for determining the amount of inorganic additives and calcium carbonate in nonwovens by thermogravimetry analysis, and proved its effectiveness.

To study the velocity and pressure distribution of the oil film in a heavy hydrostatic thrust bearing, a mathematical model of the velocity is proposed and the finite volume method (FVM) has been used to simulate the flow field under different working conditions. Some pressure experiments were carried out and the results verified the correctness of the simulation. It is concluded that the pressure distribution varies small under different rotation speed when the surface load on the workbench is constant. But the velocity of the oil film is influenced greatly by the rotation speed. When the rotation speed of the workbench is as quick as enough, the velocity of the oil film on one radial side of the pad will be zero, that is to say the lubrication oil will be drained from the other three sides of the recess.

This paper studied the effect of temperature, single surface-active agent and anionic/non-ionic surface-active agents to the viscosity of sludge-sump oil, and ditermined the optimum process conditions by orthogonal experiment. The result showed that the viscosity of sludge-sump iol reduced with the increase of temperature when below 50°C, then the viscosity decreased slowly when the temperature is above 50°C. The optimum conditions obtained by orthogonal experiment were: OP-10 0.6%, sodium dodecyl benzene sulfonate (SDBS) 0.3% and water content 35%. The viscosity reduction rate was about 98.80%.

Ceramics with the formula Ca_1-xSr_xZr₄(PO₄)₆ (x=0.4, 0.45, 0.5, 0.55) have been synthesized by coprecipitation method, an. their structures, phase transitions, thermal expansion properties have been studied by differential sanning calorimetry, scanning electron microscope, X-ray diffraction and dilatometer. The results show that Ca_1-xSr_xZr₄(PO₄)₆ ceramics sintered at 1400°C had good sintering condition. Unit cell volume basically had no change with substitution of Ca by Sr. The coprecipitation method saved energy and time. It was introduced to increase the relative density of Ca_0.5Sr_0.5Zr₄(PO₄)₆ ceramic. The coefficient of thermal expansion was about 1.447×10^-6/°C.