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This paper presents a remote equipment virtual maintenance training system architecture. The system function modules are designed. We use the open source software to develop the environment to build a complete system which based on ThinkPHP and MVC framework. Multisim circuit simulation software is nested for circuit board components positioning and fault diagnosis. The system can be used for fault diagnostics in electrical system and it can also be used to train maintenance staff.

W-doped VO2 thin films were prepared by magnetron sputtering after annealing in vacuum. The structure, morphology, infrared transmittance and phase transition were characterized by X-ray diffractometer, atomic force microscopy(AFM), infrared spectrometer (IR) and differential thermal analysis(DTA), respectively. The results show that after vacuum annealing at 500 °C for 2h, the major phase of W doped films is VO2. Dopant reduce the phase transition temperature of VO2 thin films to 21.9°C.

Silane coupling agent KH550 was used to modify the surface of nano-alumina. Ultrasonic dispersion was employed to take the place of traditional mechanical stir. Absorbency of the aqueous solution of nano-Al2O3, which had been modified, was determined to confirm that under this process condition the optimum amount of KH550 was 2.5% while the optimum time was 50 minutes. The infrared spectra indicated that the surface of nano-Al2O3 had been modified and the absorption of KH550 really existed there.

To study the impact of VDP on the bending process of fiberboard, this paper deeply researched into the dynamic changes of section stress distribution of fiberboard during the process of loading and bending and built a static bending strength predicting model, which is based on the piecewise function by simulating fiberboard VDP, theory of elasticity and plasticity, lamella inter-bedded theory and VDP model. The results show: The bending process of fiberboard can be divided into two stages which are elasticity period and elasticity-plasticity period. The latter includes both elasticity region and plasticity region, and compression region comes to elasticity bending before pulling region. The curve of bending section stress distribution is nonlinear and affected by loads and VDP. Critical section stress distribution of bending breakage and breakage load can be predicted by VDP with other condition unchanged. The value of static bending strength predicted by model is basically consistent with testing data. And the static bending strength is closely related to qualification factors of VDP. Fiberboard with high average density doesn’t always contain high static bending strength. VDP is a significant physical parameter which has impact on the bending process and performance of fiberboard, so it must be optimized and controlled in production according to for specific purpose. Key words: fiberboard, vertical density profile, section stress distribution, bending strength, predicting model

Activated carbons were prepared through chemical activation of lignin from straw pulping precursor using potassium carbonate as the chemical agent. Effects of activated temperature, K2CO3/lignin ratio and the activated time on the yield, Iodine number of activated carbon were investigated. Experimental results indicated that the optimum conditions were as follow: activated temperature 800°C, K3CO3(40% concentration) /lignin ratio 5: l, activated time 50min. These conditions allowed us to obtain a BET surface area of 1104 m2/g, including the external or non-microporous surface of 417 m2/g，Amount of methylene blue adsorption, Iodine number and the yield of activated carbon prepared under optimum conditions were 10.6mL/0.lg,1310 mg/g and 19.75%, respectively.

The Ni-based reticular MnOx catalytic materials with high porosity and high specific area were prepared by the electrodeposition method. XRD and SEM were employed to characterize the phase structure and morphology of the MnOx films before and after heat treatment. The phase structure has changed from irregular amorphous structure to compacting crystal structure on the effect of heat treatment. The results show that the phase in the film is γ-MnO2after aging. The electrodeposition mechanism of MnO2has also been studied in this paper. MnO2was deposited by the hydrolysis reaction of Mn2+ in electrolyte and the disproportionation reaction of unstable Mn3+ions. A large number of hydrogen was released during the whole deposition process.

There are some deficiencies in the former designed crack monitoring sensor, especially when crack initiates from both sides of hole. To solve this problem, a new scheme of the sensor is presented and corresponding finite element model (FEM) is established. Then the output characteristics of the sensor are analyzed by FEM. It is shown that the sensor is sensitive to cracks, and can be used to monitor the cracks initiating from the edge of the hole, no matter from left or right side. The relationship between crack length and sensor’s output is established by polynomial fitting, and it can be employed in further crack monitoring.

The hydration kinetics of carbonized spinel carbon bricks with different proportions of Mg / A1 additive has been studied in water steam of super thermostatic bath between 25°C and 85°C.The kinetic equations for hydration of the brick have been derived according to the experimental data and the theory of kinetics. Methods of various protections against hydration have been discussed. It shows that chemical reaction control occurs in the carbonized spinel carbon brick with Al and Mg at 44.3°C-84°C. The cracking time reduces from 40h to 4h with the rising of temperature verifies from 44°C to 84°C, the hydration is controlled by diffusion between 24.7°C and 33°C. And cracking does not appear after 50-day-and-night hydration at 24.7°C.

The Mg-6%Zn-5%Hydroxyapatite (HA) biomaterial had been prepared through powder metallurgy method in this investigation. The mechanical properties and biodegradable behaviors of the Mg-Zn-HAcomposite in simulated body fluid were studied. The Mg-Zn-HA specimens obtained appropriate density, adjustable elastic modulus and compatible strength to natural bones. Immersion corrosion experiments revealed that 5wt% addition of HA in Mg-6%Zn alloy exhibited acceptable corrosion rates in simulated body fluid. The Mg matrix, Mg7Zn3phase and HA are identified in the experimental composite. The Mg(OH)2and Hydroxyapatite were found on the corrosion products in the simulated body fluid.

The research presented in the paper focuses on the specific process of Gutta-percha extraction and refinement. Gutta-percha was extracted from the residues of leaves, which is based on the comprehensive utilization technology of Eucommia Ulmoides leaves. After extracted and separated chlorophyll, β-carotene, lignans, aucubin, chlorogenic acid, flavonoid, polysaccharide and proteins, etc. with the method of Multi-stage Countercurrent Extraction, the green leaves changed into the residues, which was then steeped in petroleum ether (whose boiling range is from 60 to 90°C) and generated precipitation in acetone. The results of this research indicate that: Gutta-percha extracted from the residues owns light color, which resolves the big issue that the gum was restricted for deep color in exportation. Besides, the yield of the gum in this experiment is approximate 2.0%, the increasing rate rising by 17.6% compared with 1.7% of other immediate extraction methods’. What’s more, the cost of the process flows introduced in the paper is lower than others, with less consumption, less waste and more efficient solvent circle utilization. And a new way for gutta-percha extraction was presented.

lignin (L)-based phenolic prepolymers with different phenol (P) substitution degrees were synthesized using the modified(M) L with laccase. It was found that the ML showed lower molecular value, polydispersity and higher reactivity compared to unmodified sample, and up to 30% of phenol can be substituted by MF to give LPF wood adhesive having better bonding strength in comparison to a control unmodified lignin phenol formaldehyde wood adhesive. MF was characterized using FTIR and GPC. FTIR showed that after the treatment of laccase, the methoxyl group increased, which was mainly due to the demethylation, and laccase/mediator system made the ether bonds of L cleave to produce more alcohol hydroxyl, as a result, the reactivity of ML was improved.

Wood dyeing requires a non-subjective, repeatable method for determining the color testing and matching. Previously published method used human visual perception to determine the percent of dyestuffs. In this study, computer color matching technique was applied into the dyeing of fast growing wood for the imitation of precious wood species. The process includes measuring the color of wood samples, determining dyeset, preparing and measuring basic color samples, establishing a basic database, calculating and correcting recipes. The recipe of black walnut provided by the system was as follows: acid yellow 2G 0.19%, acid green 0.59%, acid red B 0.29%, with the chromatic difference 0.12%. It could be concluded that dyeing with computer color matching technique allows for a faster, less subjective and easily repeatable procedure that is superior to simple human visual perception.

The Ti(Y)N coatings were successfully deposited onto 18-8 stainless steel substrates by the hollow cathode discharge (HCD) ion-plating method through the application of a Ti-Y(0.2 wt%) alloy evaporation source instead of pure titanium. The influence of Y on the adhesion of the TiN coating/substrate was studied. The results show that the adhesion of the coating to the substrate was evidently enhanced by adding a small amount of the rare-earth element yttrium. The Ti(Y)N coatings deposited on some punch side pins were presented and compared with the TiN coating. The service lifetime of Ti(Y)N coated the punch side pin is approximately 50% higher compared to that of TiN coated.

Studying the vertical density profile (VDP) forming progress of fiberboard helps understand and improve the hot-pressing technology. The presented work aims to investigate the effects of coreline temperature and thickness curve on VDP by changing hot-pressing curve and moisture content of mat. In doing so, it was hoped to study the VDP forming progress and manufacture “Steep-Flat” VDP and “Flat” VDP fiberboard. The results indicated that Closure phase of traditional hot-pressing curve failed to alter shape of mat thickness curve which control the shape of VDP. The mat manufactured by traditional hot-pressing curve was “Steep” VDP and could not manufacture “Steep-Flat” VDP and “Flat” VDP; Closure phase of “high-low-high” hot-pressing curve could be separated into rapid compression stage, thickness expansion stage, and second compression stage. The density of surface layer formed at rapid compression stage and decided by first high-pressure. The density gradient between surface layer and core layer formed at thickness expansion stage and decided by expansion time. The density of surface layer formed at rapid compression stage and decided by second high-pressure. The “Steep-Flat” VDP and the “Flat” VDP could manufactured by modulated moisture content of mat, first high-pressure, expansion time, second high-pressure.

The electrical potential technique was applied to monitor the crack initiation and propagation in LY12-CZ plates. The feasibility of this method was validated by a simulation experiment firstly. Then fatigue crack monitoring experiment based on LY12-CZ aluminum alloy center-hole plate specimen was carried out. After a special coating sensor was prepared on the monitoring area of the specimen by surface technology, a set of fatigue crack monitoring experiments were carried out. The changes in the potential values of the coating sensor resulting from crack damage were documented. Since the property of the coating sensor and the introduced current were constant, the measured voltage values would only relate to the crack’s length and position. Based on the experimental results, the relation curves between voltage values and crack lengths were obtained, and a set of empirical formulae were deduced.

A kind of copper multilayer coating was prepared on stainless steel substrate using ultrasonic-electrodepositing method. The microstructure, hardness, wear resistance, adhesion and corrosion resistance of it were investigated respectively. The results show that the coating exhibits a multilayer structure and the thickness of each layer is about 0.3µm. The crystallite average diameter of it is obviously smaller than that of the ordinary electrodeposited copper coating. The diffraction peaks of Cu (200) and Cu (111) for it are obviously stronger, while Cu (220) for it is much weaker. Comparative investigations on the mechanical properties show that only the hardness of it is a little lower, whereas the wear resistance and the adhesion of it to the substrate are all evidently enhanced. The average start corrosion time of it in 20％ HNO3 solution is nearly three times delayed, and the corrosion rate is obviously decreased; anode polarization curves in 3.5% NaCl solution also show that the corrosion resistance of it is greatly improved.