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By changing ther factors of synthesis process of PAE, discussed the effects of synthetic conditions on the PAE curing, and through electron microscope analysis methods, the curing mechanism of PAE is preliminary discussed.When the ratio of DTEA/AA was 1:1.05,the dry and wet strength of paper before and after curing achieved the best value.when the dosage of p-toluene sulfonic acid is 1.5%, the PAE can achieve best effect.the best ratio of PPC and epichlorohydrin is 1:0.7.

This paper mainly discuss the effect of beating on OCC pulp fiber morphology and paper physical Strength. After the treatment with PFI, the beating degree were ranged from 25 ° SR rises from 56 °SR, the fiber morphologies were greatly changed, and appeared splitting and brooming. Physical results showed that beating can improve strength properties of OCC pulp in the proper degree, 46°SR was the best result in this study.

Hydraulic press occur elastic deformations in the working status. The deformation will affect the precision of the products. This paper expounds the method of using Laser tracker test rigidity of THP11-10000A isothermal forging hydraulic press. And we test the deformation of the lower bean, fit the date and compare with fitting of the finite element simulation results. The validity and the accuracy of the simulation results are verified.

This paper used the finite element software ANSYS to simulate the thermal assembly process of the roller sleeve of the HFCG160 roller press, and study the change of the temperature field. And then, comparing the simulation temperature with the test temperature, the results show that the simulation temperature is basically consistent with the test temperature, while there are slight biases on the individual points within a certain period of time. The main reason for biases between the simulation temperature and the test temperature is that the convective heat transfer coefficient is average during the simulation, which ignoring the convective heat transfer coefficient decreases with the decreasing of temperature.

With the development of technology, the agricultural industry has become far more efficient and mechanization. In this paper, image processing method was adopted to detect the changes in seeds temperature, aiming at discovering the laws in seed germination. Oak seeds were selected as samples. The method can be divided into two steps----image segmentation, data extraction and analysis. 32400 images for 90 seeds were captured, and the changing curve of seeds temperature was described based on the images we collected. The result showed that the method was available to capture the changes of seeds temperature during its germination. Even, further research aiming at distinguishing seeds vigor by temperature information, is of great value.

In this paper, the theoretical equation of flow injection-cathodic potentiometric stripping analysis for Cl-ion determination was derived from theoretical analysis, and the experimental equation was summarized using multiple linear regression method. The result shows that the theoretical equation of flow injection-cathodic potentiometric stripping analysis for Cl-ion is: (dt/dE)max=K Apr-1/2D2/3-1/6Vf1/2teCx-/is;that the experimental equation of multiple linear regression method is: (dt/dE)max Cl-1.86×1010Vf0.568teCCl-/is. The two results are similar on Vf-average flow rate, te-concentrate time, CCl--Cl-ion concentration and isconstant current.

A kind of refractory fiber cardboard functioning as building insulation materials was developed. To improve the cardboard abilities to bear high temperature, sepiolite and alumino-silicate fibers were chosen as the raw materials for making refractory fiber carboard. In addition, inorganic adhesives and PVA fiber were used as bonding agents to enhance the physical strength of cardboard. The effect of bonding agents amount on tensile strength of the cardboard were investigated. When choosing inorganic adhesives and PVA fibers as the adhesives, the optimum condition is that amount of aluminum sol and PVA fibers is 30%and 3%-4% by weight, respectively; The best technical conditions for making the refractory fiber cardboard were determined. When the mass ratio of alumino-silicate fibers, sepiolite fiber, PVA fibers is 90: 6: 4, the physical strength of refractory fiber cardboard can be up to 1.556N·m/g. When the bulk density of the cardboard is 305.8kg/m3, the thermal conductivity of insulation cardboard at 200°C is very low, which is only 0.065W/m·K.

In this thesis, the process of electromagnetic drying cylinder was analyzed creating by the dryer finite element model using ANSYS. The conduction thermal analysis, the applied load and solved showed the results of three major components. Which create a finite element model of the process, mainly the preprocessor using ANSYS software to create or import geometric models from other software applications, and then add the material properties. The last of the geometric model meshing and solving process need to enter solvers according to the actual situation. The setting is applied to the thermal load and conditions. Then it is proceed to the finite element solution operator. It final usually the Post 1, or Post2 view results, and based on our experience to judge correctly

Aimed at the welding initial defect fatigue extension of 300t converter loop in a factory, the whole assembly finite-element (FE) model of converter loop with the welding initial defect is established. The converter loop FE model with different depth initial defect is computed by using 3D nonlinear finite element method at different tilting angles. And the stress intensity factor is extracted and analyzed under different working circumstances. The analysis results show that when the initial defect depth is greater than 11.715mm, the defect will result in fatigue crack extension at the complex alternating stress. To solve the cracking leakage problem of converter loop, the original welding manholes is replaced by the movable manhole. In the past over one year, the fatigue cracking and leaking phenomena did not occur in the converter loop, so the effect is obvious.

In order to realize the curve welding seam tracking of welding tractor, the welding tractor driven by two rear wheels is researched in this paper. The control system that a DSP controls two DC brushless motors is designed. It contains the whole system design, hardware circuit and software design. It is designed as a double closed loop system. Experimental results verified the feasibility of the whole system.

We explored a new type alloy EAM potential (CLI-EAM) that the value of atomic electron density and pair potential between distinct atoms are obtained by Chen’s lattice inversion based on first-principles calculations. The alloy CLI-EAM potential acquired from NiAl alloy can also apply in Ni3Al successfully and the results of basic properties agreed with the experiments. The results of formation energy of point defects of NiAl and Ni3Al alloy indicate that the structural defects are anti-site defects of Al when enrichments of Al atoms.

Nonsynchronous vibrations (NSVs) with high amplitude levels in the first rotor blades of a multi-stage axial compressor have been observed. The excitation is aerodynamically caused and associated with a unsteady flow field, including sound field. In order to investigate the characteristics of sound field in the axial compressor, the noise inner compressor casing are measured simultaneously with the vibration of the rotor blades on a high pressure compressor component rig testing. The results show that noise with specific frequency structures appear in the axial compressor under a pre-arranged structure adjustment and the specific operating conditions, and the noise spectrum characteristics are analyzed detailedly. Some influence factors such as rotating speed and corrected mass flow rate on noise characteristics are discussed emphatically. The results presented in this paper can be a reference for further understand of the characteristics of unsteady flow field and the effects of the high intensity sound waves on the rotor blades.

Exhaust noise is the major noise source of the internal combustion engines, and the exhaust silencer is the device to reduce the exhaust noise. Exhaust gas of the internal combustion engine is high-temperature, therefore in the study of internal combustion engine exhaust silencer, the surface temperature’s influence on the surrounding adjacent facilities should be controlled to a certain range and the status of the temperature field depends on the material and structure of the adiabatic envelope. The model of exhaust silencers discussed in this article is fluid-solid interaction model and this paper uses the CFD software for numerical simulation of the model. Using appropriate boundary conditions, calculation models and silencer model with heat transfer surface, this paper uses N-S equation and standard turbulent model to simulate the flow field and wall temperature field inside the silencer, and does post-processing analysis of the results.

This paper presents a thorough study of the wave-plate gas-liquid separators. The resistance curve has been obtained by the method of combining numerical simulation and experimental research. The separation efficiency curve under rated conditions for the droplet with different particle diameters has been obtained by using stochastic trajectory model. This can provide a new method for the research of wave-plate gas-liquid separator. The results obtained here may provide some new theoretical guidance for the development and optimal design of wave-plate gas-liquid separator.

Proprioception provides feedback that is vitally important for motor control. A deficiency in joint proprioception is thought to be associated with various upper limb rheumatological disorders. Currently, there is a lack of a portable device that could be used for measuring functional proprioception at the fingertips in the field. Therefore, a novel portable device for measuring pinch movement discrimination between index finger and thumb of either hand was constructed. This device is manually operated and requires the subject to make an absolute judgment of a joint position, choosing which one of five pre-experienced positions is being presented to them, with trials given in a random order. The 5 physical differences used were between 1.22 and 2.42cms. Reliability analysis was performed over a 7-day interval, with 8 healthy young adult volunteers. The discrimination scores, measured as the Area Under the Curve (AUC), for the group showed a mean (SD) of 0.794 (0.544) and 0.794 (0.549) on days 1 and 8, respectively. The day 1 and 8 reliability assessed with the interclass correlation coefficient ICC(3,1) was 0.85. Nondominant hands showed better pinch discrimination on the two days, with AUC values of 0.800 and 0.810 compared with 0.788 and 0.778, but these differences were not statistically significant (p>0.05). No difference in pinch movement discrimination was found between sexes. The ease of use and portability of the novel device for measuring functional proprioception at the fingertips described in this note make it ideal for measuring hand functional proprioception as part of clinical and epidemiological studies. The mid-range AUC discrimination scores found with healthy young adults mean that factors thought to diminish (eg. hand injury) or improve (eg. having expert finger skills) discrimination could be detected with the device.