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Diamond/copper composites have excellent thermal physical properties and they are usually be grinded and polished to certain roughness before sealing with other materials, in practical engineering applications. This paper studied the effects of different diamond particles on surface roughness of diamond/copper composites. Research results show that under the same grinding conditions, copper-based composites enhanced by broken diamond have smoother surface and higher bending strength; composites enhanced by monocrystalline diamond have the roughest surface and the lowest bending strength. The difference of the roughness and bending strength is attributed to surface morphology of the diamond and the bonding strength between particles and matrix.

Because of the complex geologic space body and the underground seepage conditions, it is difficult to predict groundwater water inflow in prevention and treatment control work of coal mine. To predict the groundwater flow of the coal seam under the roof sandstone aquifer in Nanshan coal, the big water well method and three-dimensional numerical model were used at the same time. The quantity of predicted normal water inflow was 553.5 m3/h by using numerical model and the big-well method is about 591.6 m3/h. The result of big-well methods was relatively close to the result of numerical simulation method, which proved the rationality of the two methods in parameters selection and model building, and greatly improved the reliability and accuracy of prediction results. Compared with large-well method, by establishing the complex 3D geological structure of underground water and fitting the parameters based on the actual data of hydrology, numerical method could simulate the process of groundwater seepage and dewatering engineering, overcome the parameter uncertainty of large-well method, improve the predictive accuracy of the mine water inflow, and has important application value.

High volume fraction diamond/copper composites with different diamond shape were prepared by vacuum pressure infiltration. In this paper, the effect of diamond type on thermo-physical properties of the composites was researched. The results showed that the composites with broken diamond exhibited the lowest thermal conductivity and coefficient of thermal expansion, only 401W/m•k and 6.2×10-6m/K respectively, and the composites with monocrystalline diamond had the best properties, reaching to 527W/m•K and 8.3×10-6m/K respectively, and the properties of the composites with modified-shape diamond were in the middle. The difference in the properties of the composites with different-shape diamond is attributed to their various specific surface areas.

This paper took the regional product quality asthe object of study. Firstly this paper took advantageof PESTEL model tostudy factors of regional product quality from the enterprise external environmentand strategic perspective. Built regional product quality indicator system ofsix aspects from political, economic, social,technological, environment and legal. Then established evaluation modelby gray relational analysis model. The next step is to analyze the variousfactors by expert scoring method. The results can show the influence degree offactors. Scienceand technology spending, Regional GDP are Local fiscal revenue are the topthree important factors. Finally, based on the evaluationresults of the analysis, provided a reference for improving the quality ofregional products.

Fused quartz granules (d50=19 μm) were used as raw material, and B4C-Si3N4 (1:1, in mass) was used as additive with dosages of 1% (in mass, similarly hereinafter), 2% and 3%. Fused quartz ceramic materials were fabricated in reduction atmosphere at 1250 °C, 1300 °C, 1350 °C and 1400 °C for 1 h. The apparent porosity, bending strength and thermal expansion ratios of the samples were examined and they were analysed by means of XRD. The results showed that the sample sintered at each temperature with 1% B4C-Si3N4 had the lowest apparent porosity, the highest bending strength. This indicated that 1% B4C-Si3N4 was conducive to sintering of fused quartz ceramic materials. The results of XRD analysis and thermal expansion ratio analysis showed that 1% B4C-Si3N4 compound additive had obvious effect on inhibiting crystallization of the samples sintered at various temperatures. It can be deduced that the 1% B4C-Si3N4 compound additive plays the excellent role in inhibiting crystallization and facilitating sintering of fused quartz ceramic materials.

The absorption rates of CO2 in diethanolamine (DEA) promoted N-methyldiethanolamine (MDEA) aqueous solution were measured at normal pressure with temperatures ranging from 303.15-323.15K. The influence of temperature and the mass fraction of DEA on the absorption rate of CO2 was illustrated.

The intake system sub-model, the fuel dynamics sub-model and the power output sub-model are studied in this paper based on Elbert Hendricks engine mean model. Engine output characteristics using computational model is established in MATLAB/Simulink. Parameter of the modeling and simulation process is obtained through experiments, and finally, the engine bench test is done, and compared it with the simulation curve in same conditions. The results show that the model calculation has smaller error, higher precision, and which can meet the basic requirements of the engine modeling in actual control.

In terms of the chaotic signal needed by encryption, it is the more complicate the better. In addition, the frequency range of chaos should be wider than that of signal to be encrypted. However, chaotic spectrum usually is a narrow area in the low frequency region, and the complexity is not high enough. The signals encryption effects are affected. In order to solve this problem, this paper used the chaos transformed by unary polynomial to encrypt signals. Under the Matlab simulation environment, it is confirmed from time-domain and frequency-domain perspectives that the encryption effect of transformed chaos is better. Even the higher frequency signal can also be covered up completely. At the same time, the difficulty of decoding the encrypted signals is greatly increased, and the anti-attacking capability is strengthened.

When the chaos is degenerating, the unary polynomial transformation can make the chaotic signal more complicated. Therefore, the transformed chaotic signal is more suitable for image encryption. In this paper, the image is respectively encrypted by the chaotic signal transformed by different unary polynomials and the chaotic signal without transformation. And then their encryption effects are compared and analyzed by various criteria. Experiments and research results indicate that, after unary polynomial transformation, the effect of chaos-based image encryption is improved. Furthermore, different unary polynomials have different effects on the cipher image. It can make the effect of image encryption better by changing the form of unary polynomial.

Stress of pressurizer surge line due to stratification is calculated with the help of finite analysis software, using both simplified temperature distribution and the temperature fields of CFD simulation result. Stress and displacement of pressurizer surge line are achieved. Evaluation of the fatigue life reduction due to stratification is done by using modified fatigue design curve and referring to environmental fatigue factor. The conclusions here indicate that it can’t be neglected that stratification reduces the fatigue life of pressurizer surge line.

SO42-/TiO2 catalysts prepared by precipitation and impregnation method were used for the dehydration of carbohydrates into 5-hydroxymethylfurfural in aqueous solution. Effects of various parameters and catalyst reuse towards catalytic performance of SO42-/TiO2 were studied in detail. Experimental results showed that calcine temperature and acid concentration had significant influence on the essential catalyst properties. SO42-/TiO2, treated with 0.50 mol/L H2SO4 and calcined at 773 K for 3 h, showed the best catalytic effect. The recovered catalyst after calcination was found to show slower deactivation rate compared to those without calcination.

Surfactants from modified lignin have received growing attention recently. Lignin is an inevitable by-product of the chemical manufacturing processes for cellulose and pulping. Furthermore, this class of chemical has vast availability around the world. Due to the interactions of hydrophobic and hydrophilic groups on the interface, lignin modified surfactants present favorable surfactivity. In this paper, alkali lignin (AL) suffered the liquefaction treatment into liquefid alkali lignin (L-AL), of which major constituents were lignin-phenols. Hydrophilic modified L-AL was synthesized with epoxy chloropropane then with polyglycol. The surface tension, watersolubility and HLB value of the productions were characterized. Then the surfactant was applied to the experiments of foam properties, detergency and emulsifying power. The results showed that the modified surfactant had fine solubility in water, relatively higher HLB value of 16.26 and lower surface tention. The production had lower foaming power and foam stability. Though its decontamination performance was relatively weak，however the emulsifying power presented pretty well.

In this paper, a new component assembly library for mechanical devices is presented. Component modeling is the key technology, and component library is also an important functional module, which is a tool for instruction design in the mechanical devices. Mechanical properties are mentioned. Interactions between the component design process and the component library are realized. This paper covers the details about the implementation of the component library. The process of traditional mechanical design is simplified with the component library. Consequently, the design and development time for mechanical device instructions can be significantly shortened.

The assembled monolithic compound spiral reinforced concrete column in this paper is a kind of concrete column reinforced by high-strength compound spiral stirrups and jointed by local steel tubular and bolt reinforcement. Experiments of four specimens under low cyclic loading and different axial compressive loads are carried out, and the result testifies that the anti-seismic property of these measures is not worse than the integral compound spiral hoop columns under the same load.

Diamond/Cu composites were fabricated by pressure infiltration method with Cr coating onto the diamond particles. The major challenge in the development of these composites is to obtain a well bonded interface between diamond particles and Cu. In this paper, an effective way to apply molten salt method coated chromium on diamond particles was used to solve the interface problem. The results showed that the bonded interface thickness of about 1μm was obtained. The relative density and thermal conductivity of coated composites were 99.5% and 396W/m K respectively, which were remarkably enhanced compared to that of uncoated composites.

The motion characteristic of key components is a decisional factor to the working reliability and stability of a package machine. In this paper, the motion simulation of a key component is carried out in the ADAMS software environment. By analysis of the force, variance of the center-of-mass and the moment of the component, the mutation point in the motion is found, and then the structure is optimized by selection of different structural parameters. The optimization result shows a significant improvement for the reliability and stability of the whole machine.

Traditional touch measure method has the shortages of easily distorting cigarette filter rod, long measure time, not high measure precision and not online implementing. In order to overcome these, imaging measure technology is used to measure it. Firstly, preprocessing filtering is operated on the acquired image. Then sobel operator is used to detect the edge and binary filter rod target image is obtained through morphological processing after falsehood edge eliminating. After that correlation parameters are gained. Parameters measuring absolute error for two images acquired from the same filter rod under different illumination is 1.848%. Experiment proves that the proposed method can rapidly and correctly measure cigarette filter rod. It can effectively measure filter rod in practice.

Fused quartz granule (d50=10μm) was used as raw material, and Al2O3-AlN (1:1, in mass) was used as additive with dosages of 1 wt%, 2 wt% and 3 wt%. The crystallization characteristics of fused quartz ceramic fabricated in reduction atmosphere at 1300°C, 1350°C and 1400°C for 1h has been investigated by thermal expansion ratio and XRD. The results showed that the crystallization characteristics were markedly improved by 1 wt% AI2O3-AIN compound additive. 1 wt% Al2O3-AIN had obvious effect on inhibiting crystallization of the samples sintered at various temperatures. The apparent porosity, bending strength and SEM of the samples were also examined. The results showed that the samples with 1 wt% AI2O3-AIN had the lowest apparent porosity among the samples containing Al2O3-AlN, the highest bending strength, and the sample AA1 sintered at 1350°C had more compact microstructure, which indicated that 1 wt% Al2O3-AlN was conducive to sintering of fused quartz ceramic materials. It can be deduced that the 1 wt% Al2O3-AIN compound additive plays the excellent role on inhibiting crystallization and promoting sintering of fused quartz ceramic materials.

Global warming is one of the problems paid close attention extensively in the world today. Meanwhile, the development of the world economy demands more and more oil, coal and other energy, which results in an unceasing increase of greenhouse gas emissions and intensifies the climate change. The development of the low-carbon economy has become an important means to address climate change issues to a country, and the carbon tax is an important approach to achieve the development of the low-carbon economy. This paper is based on the perspective of the low-carbon economy, starting from the role of the tax on the economy to study the role of the tax on the low-carbon economy, and ultimately to design the implementation of the tax .

Optical microcavities confine light to small model volumes and have ultrahigh quality factor (Q), especially microtoroid cavities, having very broad application prospects. In this paper, we use MEMS (Microelectromechanical System) skills, such as lithography, dry etching to fabricated silica optical microdisks. And after that, a novel processing method based on CO2laser reflow technology is introduced to create microtoroid cavities. The processing details are discussed including light path, laser power and other important parameters. The quality factor of the planar microtoroid cavity was measured by taper-fiber coupling and the average value reach 4.8×105.

Bagasse alkali lignin is the primary constituent of pulping black liquor. The phenolic products such as phenol, 2,6-dimethoxy-phenol and 2-methoxy-phenol were obtained by catalytic liquefaction from bagasse alkali lignin, with the aim of enhancing its use value. In the investigation, under optimal conditions, using SiO2-Al2O3 or FeS as catalyst, the phenols yield reached 54.10% and 55.18%, respectively. HPLC spectrum showed that the phenolic products of them were different. FT-IR and H-NMR spectrums showed that, using SiO2-Al2O3 as the catalyst, the α-O-4 and β-O-4 ether bonds and C-Cα bonds of lignin units were prone to break, forming 2,6-dimethoxy-phenol, 2-methoxy-phenol and phenol. While FeS action was more difficult, the α-O-4 and β-O-4 ether bonds and Cα-Cβ bonds of lignin units broke down. Then, the introduction of additional hydroxyl groups from glycols consequently increased the final product solubility. At the same time, Cα–C bond of the phenylpropane linkage was broken to produce phenolic chemicals. Third, part of the phenylpropane linkage was prone to break Cα–Cβ bond and structural rearrangement occurred. So the content of 2-methoxy-4-methyl-phenol and the total yield of phenols were high.

Fused quartz granules (d50=19 μm) were used as raw material, and Si3N4-Y2O3 (1:1, in mass) was used as additive with dosages of 1%, 2% and 3% (in mass). Fused quartz ceramic materials were fabricated in reduction atmosphere at 1300 °C, 1350 °C and 1400 °C for 1 h. The effect of Si3N4-Y2O3 on crystallization and sintering of the fused quartz ceramic materials were researched by measurements of apparent porosity, bending strength and thermal expansion rate (RT~1200 °C), and by the analyses of XRD and SEM. The results showed that the samples sintered at each temperature with 3% Si3N4-Y2O3 had the lowest apparent porosity, the highest bending strength and more compact microstructure. This indicated that 3% Si3N4-Y2O3 was conducive to sintering of fused quartz ceramic materials. The results of XRD and thermal expansion rate showed that addition of 3% Si3N4-Y2O3 compound had obvious effect on inhibiting crystallization of the samples sintered at various temperatures. It can be deduced that the Si3N4-Y2O3 compound plays the best role in inhibiting crystallization and facilitating sintering of fused quartz ceramic materials.

Fused quartz granules (d50=19 μm) were used as raw material, and Gd2O3-Nd2O3 (1:1, in mass) was used as additive with dosages of 1% (in mass, similarly hereinafter), 2% and 3%. Fused quartz ceramic materials were fabricated in reduction atmosphere at 1300 °C, 1350 °C and 1400 °C for 1 h. The apparent porosity, bending strength and thermal expansion ratios of the samples were examined and the samples were further analysed by means of XRD and SEM. The results showed that the sample sintered at each temperature with 3% Gd2O3-Nd2O3 had the lowest apparent porosity, the highest bending strength and more compact microstructure. This indicated that 3% Gd2O3-Nd2O3 was helpful to sintering of fused quartz ceramic materials. The results of XRD and thermal expansion ratio analysis showed that 3% Gd2O3-Nd2O3 compound additive had better effect on inhibiting crystallization of the samples sintered at 1300 °C and 1350 °C, but had a little effect on inhibiting crystallization of the sample sintered at 1400 °C.

Fused quartz granules (d50=19 μm) were used as raw material, and Si3N4-Nd2O3 (1:1, in mass) was used as additive with dosages of 1% (in mass, similarly hereinafter), 2% and 3%. Fused quartz ceramic materials were fabricated in reduction atmosphere at 1300 °C, 1350 °C and 1400 °C for 1 h. The apparent porosity, bending strength and thermal expansion ratios of the samples were studied and the samples were further analysed by means of XRD and SEM. The results showed that the sample sintered at each temperature with 3% Si3N4-Nd2O3 had the lowest apparent porosity, the highest bending strength and more compact microstructure. This indicated that 3% Si3N4-Nd2O3 was useful to the sintering of fused quartz ceramic materials. The results of XRD and thermal expansion ratio analysis showed that 3% Si3N4-Nd2O3 compound additive had better effect on inhibiting crystallization of the samples sintered at 1300 °C, 1350 °C and 1400 °C.

The paper presents concepts of permeable reactive wall, groundwater aeration, in-situ chemical oxidation, in-situ electrokinetic remediation, bioremediation, and the progress of their researches are discussed. Situ remediation of petroleum contaminants in groundwater proposed a variety of technologies should combine to improve the repair efficiency and reduce capital investment.

In recent years, due to population growth, increasing demand for the food and human disturbance to natural ecological processes etc, the nitrate pollution to water body is serious throughout the world. Based on the harmfulness of nitrate pollution, this article reviewed the contamination sources of nitrate in surface water and groundwater and the control measures in the present research. Based on the previous research, the research direction and emphasis were proposed in this paper.

Fused quartz granules (d50=19 μm) were used as raw material, and B4C-Yb2O3 (1:1, in mass) was used as additive with dosages of 1% (in mass, similarly hereinafter), 2% and 3%. Fused quartz ceramic materials were fabricated in reduction atmosphere at 1250 °C, 1300 °C, 1350 °C and 1400 °C for 1 h. The apparent porosity, bending strength and thermal expansion ratios of the samples were examined and they were analysed by means of XRD and SEM. The results showed that the sample sintered at each temperature with 3% B4C-Yb2O3 had the lowest apparent porosity, the highest bending strength and more compact microstructure. This indicated that 3% B4C-Yb2O3 was conducive to sintering of fused quartz ceramic materials. The results of XRD analysis and thermal expansion ratio analysis showed that 3% B4C-Yb2O3 compound additive had obvious effect on inhibiting crystallization of the samples sintered at various temperatures. It can be deduced that the 3% B4C-Yb2O3 compound additive plays the excellent role in inhibiting crystallization and facilitating sintering of fused quartz ceramic materials.

The globalization of modern society made the multi-urban culture faced with the globalization of information resources and environment impact. How the urban local culture updates during the interwoven and conflict with the world culture becomes the key problem during the process of urban space circle development. This paper begins with the negative impacts of the loss of localization on the circle development of the cultural forms, and then puts forward solutions in the optimization of local cultural forms in urban space level.

In order to adapt the use of workover rig for offshore completion and workover operations, it generally uses two different drive mode of milling, downhole motor and surface turntable, in dealing with deep inclined well permanent packer issues. In this thesis, the material property of pipe strings is analyzed and the axial forces, torques and frictions and other mechanical calculation models of the pipe string are established under two kinds of drive modes. Through the results of analysis of pipe string force, it analyzes the material property of permanent packer, optimizes the parameters of downhole tools and operation methods in milling operation.

This paper analyzes the deformation and strength under horizontal dynamic load of the model which acquired the first prize on the 3rd Structural Design Contest of Shandong Universities. The bearing capacity and stability of the model are verified by loading experiment. This contest provides a platform for college students to broaden their view and practice their innovation ideas. This contest make students’ creative thinking get a full training and display.

Aiming at the fatal flaws of the traditional diagnosis methods for the large-scale photoelectric tracking devices, such as poor stability and adaptive capacity, lack of inspiration and narrow domain knowledge of expert system, etc, more importantly, fundamentally improve the diagnostic efficiency and universality, in this paper, an intelligent mixed inference diagnosis expert system based on multiple knowledge representation and BP neural network is put forward. Firstly, some related key basic concepts and principles of intelligent fault diagnosis technology and several major applied diagnosis knowledge representation methods such as diagnosis fault tree, frame representation production rule and so on, were elaborated. Secondly, in view of high concurrency and relevancy of the system faults, a mixed reasoning mechanism combining BPNN and ES was researched. Finally, some interrelated essential implementation techniques, such as system architecture and VR technology, were also presented. Actual applications and experiments demonstrate that the proposed approach is robust and effective.

A new bionic biped walking mechanism (BWM) was put forward in this paper. Simple in construction, easy in control and droved by usual motor are all advantages of this mechanism. But disadvantage should not be ignored. Especially up and down bumpy of the centroid will influence the smoothness of the motion during walk. Through theoretical analysis of kinematics, motion characteristics and the movement of the spindle were obtained in a circle. To aim to bring down the uneven of the BWM, the relationship of all parameters was found and the scope of the fluctuation was established. In the end, all of the results were verified by simulation program of Matlab. The result provided theoretical guidance for optimal design of the mechanism in the further research.

Planar Microtoroid cavities have important application in many researching and application domains due to their ultrahigh quality factor (Q). But the special toroid structure can not be fabricated through traditional technology. In this paper, a novel processing method for fabricating microtoroid cavities using high-power CO2 laser after a series of traditional processing steps is introduced. The processing details are discussed including light path, focusing system and other important parameters. Test using scanning electronic microscope and laser-Raman spectrum shows that fabrication of planar microtoroid cavity using CO2 laser is feasible. The final microtoroid cavity is fabricated with slight impact to the silicon strut-beam, ensuring excellent optical performance in Planar Microtoroid cavity.