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PP/EPDM blends were prepared by dynamic vulcanization technology within a HAAKE torque rheometer. The effect of different plastic/rubber ratios of PP/EPDM blends on the curing behavior and crystallization kinetics were investigated. The obtained results showed that the plastic/rubber ratios played an important part in the solidification process as well as the crystallization kinetics. With increasing EPDM content, the cooling rate of PP/EPDM blends was significantly larger than that of neat PP. When PP content was 20 wt%, the crystallinity of PP was obviously larger than that of neat PP. Compared with neat PP, the crystallization temperature of the blends were remarkably shifted to the lower temperature. EPDM particles showed active effect on the nucleation process of PP during the cooling crystallization of the PP/EPDM blends.

Nanostructure WC composite coatings were prepared on surface of Q235 steel by argon arc cladding injection using microstructure WC feeding which were prepared by nanostructure WC powder. The microstructure of the coating were analyzed by scanning electron microscopy (SEM). Phase of the coating were analyzed by energy dispersive spectrometer and X-Ray diffract meter, moreover, microhardness and wear resistance were texted by Microhardness tester (HVST-1000) and friction wear testing machine (MMS-2A). The results show that the combination of coating and substrate is metallurgical bonding. and no Pores and cracks were founded in bonding area. aggregated nanostructure WC particles and nanostructure WC particles uniformly distributed in the coating. The maximum hardness of the coating is 1461 HV. Compared with the Q235 steel, the wear resistance of the coating increased about 15 times.

In this paper, based on the analysis of cross-section of steam oxidation of Super304H sample at 600°C, thermal stress contours were obtained by using finite element analysis through establishing geometric model and refine meshing. After extracting the stress in the interface of oxide layer and analyzing the thermal stress, it can be found that there exists compressive and tensile stress in the interface between substrate and scale, which is affected by the slope of the interface.

The Analytic Hierarchy Process (AHP) method presented in this paper is used to analyze three representative exterior wall assemblies from the perspective of manufacturers, designers, and consumers. Considering technical, economic, social, and environmental factors, a model and subsequent indicators were developed for qualitative and quantitative analyses. The approach discussed in this paper originated as a response to recent building code changes in China, and the need for value-engineers to better understand a set of newly developed wall construction assemblies in a way that minimizes subjective errors in the value-engineering evaluation process.

TiO2-organosilicone based hybrid catalysts functioned by Keggin-type heteropolyacid, TiO2-Si (Et)Si-H3PW12O40, were prepared via one-pot co-condensation method in the presence of a triblock copolymer surfactant (F127). The materials were well characterized by FT-IR, UV-vis DRS spectroscopy methods, and X-ray diffraction analysis to confirm the hybrid structure, to investigate correlation among TiO2-organosilicone matrix and H3PW12O40. Phtocatalytic tests show that, with a little amount of organosilicone and hybridization, the composite exhibits higher photocatalytic activity when decomposing the Rhodamine B ( RhB ) than anatase TiO2.

Energy Supply and demand, and carbon emission constraints are the problems that must be considered in the process of rapid economic development by national and every province. Under the constraints of energy supply and demand, and carbon emissions, there has practical significance to rational allocate regional energy utilization. With carbon pinch method, this paper research the energy allocation of Tianjin, establish analysis model. Considering the overall and regional energy demand and carbon emission constraints, to determine the usage amount of every kind of fossil energy and clean energy, in order to achieve the best energy structure and optimal balance between energy supply and demand. To provide scientific evidence for local government to make reasonable energy supply and carbon emission constraint index.

Enzymatic hydrolysis lignin was prepared and used to converse into aromatic aldehydes by catalytic wet oxidation with activation of Fenton reagent. The results demonstrated that the enzymatic hydrolysis lignin was a suitable raw material for the preparation of aromatic aldehydes. Orthogonal experiments were conducted to obtain the optimum preparation conditions. The effects of activation time, activation temperature, ratio of liquid to solid and pH of the reaction system on the yield of aromatic aldehydes were dealt with in this paper and optimal activation conditions were obtained as followed: the pH of activating reaction system was 4, activation temperature was 60°C, ratio of liquid to solid was 20:1 and activation time was 30 min. The highest yield of 13.74 % was obtained under the optimum conditions.

Utilization of wheat straw for bio-based chemicals production is a research focus. In this work, experiments were conducted to study the preparation conditions of activated carbon from formic acid hydrolysis residue of wheat straw applying response surface methodology. The effects of activation reaction temperature, retention time and activator quantity on the decolorizing capacity of activated carbon were dealt with in this paper. Optimal preparation conditions were abtained by response surface methodology as followed: the content of ZnCl2 solution was 14.2%, reaction temperature was 798°C and retained time was 30 mins with a decolorizing capacity of 15.8 mL methylene blue. Results indicated that the technology was available.

In order to achieve the carbon reduction targets committed by China, Liaoning Province must take the way of low-carbon economy. Based on the related Statistical Yearbook data, applying the IPCC carbon emissions equation and Kaya model, this paper analyses the influencing factors of the carbon dioxide emissions produced from the power consumption of Liaoning Province. and then put forward some suggestion on reducing carbon emissions. The results show that Liaoning Province can achieve the goal, but unit GDP CO2 emissions reduction is mainly due tothe investment expansion of the second industry and construction industry investment expansion. As a result, it puts forward some suggestions.

The performance of the aluminum alloy makes it the most popular lightweight materials for the automobile manufacturers. However, due to the disparity on the crystal structure,it has the higher springback values compared with steel. In order to solve the problem, we put forward a new springback compensation method based on displacement compensation principle and the principle of curved surface fairing design methods. Though full cycle simulation and calculate springback value for each working procedure, then generate the springback compensation surface. The methods practical application effect is good.

Monte Carlo (MC) method and molecular dynamics (MD) are combined to analyze the influence of ageing on mechanical properties of machined nanostructures. Single crystal copper workpiece is first cut in MD simulation, and then the machined workpiece is used in MC simulation of ageing process, finally the tensile mechanical properties of machined nanostructures before and after ageing are investigated by MD simulation. The results show that machining process and ageing have obvious influence of tensile mechanical properties. After machining, the yield strength, yield strain, fracture strain and elastic modulus reduce by 36.02%, 28.86%, 20.79% and 7.16% respectively. However, the yield strength, yield strain and elastic modulus increase by 4.84%, 1.41% and 1.02% respectively, fracture strain reduce by 24.53% after ageing process. To research the ageing processes of machined nanostructures by MC simulation is both practical and meaningful.

A three-dimensional model of Monte Carlo (MC) simulation is proposed to study the effects of ageing on the surface quality of machined nanostructures. The model includes the utilization of the Morse potential function to simulate the interatomic force between the atoms in workpieces. The results show that the ageing processes have important influence on the surface morphology and internal structure of machined workpiece. Most of the disordered point defects and one large stacking fault structures in machined workpiece disappear after ageing, but still some defect structures remain. In addition, distribution of atomic potential and atomic stress in the workpiece become regular in the aging process, and the atoms of the defect structures have much higher potential energy and stress. Finally, surface roughness of machined workpiece definitely increases after ageing. To analyze the morphology of machined surface after ageing is very practical and meaningful.

Under microwave irradiation, the ternary CuMgAl-HTLcs precursors were synthesized and MoO42-was loaded on the surface of these HTLcs. The results of XRD, FT-IR and SEM analysis indicated that the Mo anion was successfully loaded on the surface of the CuMgAl-HTLcs precursors. The activity of CuMgAl-31 for phenol hydroxylation was the highest, the conversion of phenol was 42.88% and ratio of catechol to hydroquinone was 2:1. CuMgAl-Mo-HTLcs advantageously increased the selectivity of hydroquinone with the ratio of hydroquinone to catechol reaching to 6:1 and about 4% conversion decreasing. Proposed the reaction mechanism of phenol hydroxylation by MoO42-supported HTLcs.

X-ray Fluorescence was used to determine the content of 25 inorganic elements in Chengdu dust in this article, and enrichment factor was used to analyze its distribution characteristics and source apportionment. The results showed that Cr was the extremely severe pollutant, with its average concentration of 64.57μg/g, the average enrichment factor coefficient of 477.79, which was more than 10 times higher than background value, suggested it was significantly contributed by the anthropogenic sources. Ca was the heavily polluted element, with its concentration of 7.71μg/g in average, and the average enrichment factor coefficient being 12.26, which was more than 10 times of the background value, showed it was also affected by the anthropogenic sources. The enrichment factor coefficient of Na, As, Co, Cu, Mn, Ni, Pb, Se, V, Zn, K, Mg, Br, Cs was about 1 in average, illustrated that they were not obviously affected by the man-made pollution.

The optimal conditions of prepared magnesium hydroxide using dolomite as raw material were systematically explored by carbonization. The influence between the factors of reactions and the extraction rate of magnesium hydroxide was studied. The structure and composition of product were analyzed by Fourier transform infrared spectrometer, X ray diffraction and electron microscopy. In the conditions, the extraction rate could be up to 90.32%, and its crystal was a hexagonal-type. This method has many kinds of advantages, such as simple operation, low costs of production, eliminating the environmental pollution and comprehensive utilization of by-products.

A novel processing way for the continuous helicoid reflective mirrors is proposed. We use an intelligent oven to accurately control the glass temperature and successfully produce a helicoid reflective mirror in B270 glass. Then we test the shape and optical properties of the helicod reflective mirror via the three-coordinate instrument measuring and interference experiment.

This paper provides a review of Monte Carlo (MC) method and its applications in mechanical engineering. MC simulation is a class of computational algorithms which require repeated random sampling and statistical analysis to calculate the results. The basic principles, formulas and recent development of Monte Carlo method are firstly discussed briefly, and then the applications of MC simulations in the design and manufacturing of nanostructures are reviewed. Finally, we briefly introduce MC simulation of morphology evolution of machined surface, which come from our recent work.

According to the characteristic of plate rolling process and the on-line applications, the non-homogeneous wear and thermal expansion of rollers, the elastic recovery and thermal expansion of work pieces, the variation of oil film thickness and the zero point deviation, which influence the precision of gap setting model, are analyzed. Based on the results of analysis, a high-precision gap setting model is proposed, and a zero point correction method is developed, in order to avoid overshoot, damp coefficient, which is affected by the thickness of work piece and zero point deviation are considered, is introduced. On-line applications indicate that the gap setting model improves the precision of gap setting and laid a good foundation of further improvement of thickness accuracy.

In order to analysis the effect of leveling strategy on the quality of plate products, the curvature integration by elastic-plastic differences was adopted to simulate leveling results by different leveling strategy. It had studied plastic deformation ratio, residual stress, residual curvature and leveling force for different leveling strategies to find the effectual strategy and the adaptability conditions were given. Additionally, static pressure leveling with the time delay strategy was analyzed, which was proved to be an effectual strategy to resolve the leveling problem for high strength thicker plate by a certain 3500mm mill plate.

In order to investigate the mechanical properties of single crystal Cu nanorod with preset defects, the multiscale unixial tension simulation models of nanorods with two different crystallographic orientations are established. In two orientations, the dislocations are emitted firstly from the notch tip. The results show that the defect evolution, stress-strain curves and train energy vary with different crystallographic orientations. In setup, the deformation is ductile mode and it is fracture fashion in the setup.

In order to calculate the parameters of roller leveling process, the 3D mathematical models of plate leveling based on the curvature integral by elastic-plastic differences were set up. The calculation results by the models showed a good correlation with the measured data from a plate mill which adopts the advanced control system by SMS. The analytic models can be developed which analyzed the leveling process so efficiently that it can be used for process controlling. Additionally, the plastic deformation ratio was analyzed which can account for the leveling phenomenon, and the model was regressed which can be used easily for engineering calculation.

Air cooling may decrease rolling efficiency in controlled rolling for needing long holding time to obtain the correct rolling temperature because of small cooling rate. The intermediate cooling can increate the cooling rate, and improve rolling efficiency. Experiment was carried out to research the effect of intermediate cooling on rolling efficiency. The influence of different cooling mode on the temperature distribution and the temperature profile characteristics of different cooling strategy are analyzed with FEM. It shows that intermediate cooling can decrease the holding time effectively, and improve rolling efficiency; the temperature homogeneity in thickness direction can be improved by opening the header one after another and cooling the plate by oscillating cooling.

Asymmetrical conditions that occur during plate rolling can cause front end bending or lead to poor product shape, profile, quality and cause reduced productivity. In these investigations, a model of calculating curvature is deduced according to the theory of rolling, which has been used to determine the effect of surface friction mismatch on the direction and severity of curvature in plate rolling. Results show that the front end bending can occur easily due to the mismatch of coefficient of friction. Moreover, the results have identified that the bending inclination of large reduction, large radius of roll and thin rolling stock is higher than that of the reverse, the bending inclination of the entrance thickness of rolling stock is higher than that of the reduction, and the bending inclination of the reduction is higher than that of the radius of roll.

A kind of experimental platform for in-situ nanoindentation and scratch test has been developed, which has high resolution of displacement and can be used to carry out nanoindentation and scratch test. The precision driven element composing of flexure hinges and piezoelectric actuator was analyzed, which was used to realize indenter’s precision motion. The components, working principle and performances of testing platform were introduced. The calibration experiments of loading and displacement sensors were carried out, and it showed loading and displacement sensors had high linearity and stability. The indentation experiments were carried out on a kind of glass. The experimental results showed proposed testing platform had good reproducibility and scheme was feasible. The research work will provide theoretical foundation and key technologies for nanomechanics test, and has theoretical significance and application value to materials science, micro-electronics, precision optics and biomechanics, etc.

Based on the character of plate rolling, the temperature model was developed by considering the influence of radiation, convection, water descaling, and roll conductivity and deformation energy. The factors affect the finishing temperature of the plate were analyzed, including the holding time during control rolling, rolling speed, slab temperature and pass number. Holding time, rolling speed and slab temperature have significant influence on finishing temperature, and pass number has great influence on finishing temperature of thick plate, but has little on finishing temperature of media plate.