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This paper presents the results of a systematic dry hobbing experiment performed on a general mechanical transmission type of hobbing machine. All four types of coated HSS hobs demonstrate satisfactory cutting performance applicable enough to practical production. Some related details such as the characteristics of hob wear, the effect of chip crush behavior and cutting speed are also discussed based on the experiment results.

Taking Ce (NO3)3•6H2O as cerium source, CeO2 nanosheets, CeO2 nanorods and CeO2 nanotubes were prepared using hydrothemal process. Characterization of chemical structure and surface properties for these materials was carried out and their efficacy in the catalytic ozonation degradation of wastewater was investigated. The results showed that the surface morphology and reaction conditions played great role in the removal of organic compounds. It was found that the CeO2 nanotubes showed superior catalytic activity. When 0.5 g of CeO2 nanotubes and 15 mg/min of ozone were applied in catalytic ozonation, the mineralization rate reached 97% after 2 h treatment for 1 L of model wastewater containing lemon yellow with 100 mg/L TOC.

Based on the scientific design, development, application, evaluation and management of study processes and teaching resources in PE teaching in higher education, centered by the educational ideas of human centered and health first, this study explored the development and application of computer supplementary software of CAI, CAT, CMI in PE teaching, widened the new study channel of students! development and research study mode, cultivate students! Creativity and practical ability, improve thoroughly students basic sport knowledge, basic techniques, physical fitness and the level of health, therefore enhance the modernization of PE teaching, measurement, educational management methods in PE teaching of higher education.

With the help of modern learning theory, educational media theory, systematic science theory and modern teaching design theory, the mode of making multimedia CAI courseware for technique teaching in physical education courses was designed. Based on this mode, the Multimedia CAI Courseware for Back Layout Teaching has also been made. By application in teaching, a conclusion that there are five advantages of using the Multimedia CAI Courseware for technique teaching in physical education courseware was reached, and three different levels of software and hardware should be prepared for the multimedia CAI courseware teaching. Thus, the three-chain teaching mode for using the multimedia CAI courseware in technique teaching was constructed.

As technology advanced, moving target tracking system is used more and more widely. But the traditional tracking systems are much restricted of imaging and tracking devices. This paper developed system based moving target tracking which could have a broader scope of application. The system does not have to be limited to tracking devices, but the application of the model matching technique and IMAQ Vision modules of Labview environment to form the framework of the virtual instrument system, and finally through the experiment to verify the practicality of the system.

On the basis of field environmental investigation and monitoring, the environmental radioactivity background of Xinchang and Jijicao rock in Beishan preselected region has been preliminary investigated and studied, and the public dose from local natural background radiation is estimated which can provide basic data and information for environmental impact assessment and safety assessment of HLW(the high level radioactive waste) disposal repository in the future. From the result of investigation and study, the environmental radioactivity of Xinchang and Jijicao rock is generally within normal natural background. The effective dose to local resident from natural background radiation is 2.110 mSv/a by internal and external exposure.

In this paper, the authors discuss the influence of touch trigger probe system on CMM measurement performance based on measurement experiment results. A ring gage and a plug gage finished in high accuracy are employed as test pieces and the measurements performed under the conditions of combining different extension bar and approaching speed. Two main types of errors, periodic component and high frequency undulation, are verified. Introduction of the extension bar may significantly aggravate the accuracy and reliability, especially, associated with a comparatively large approaching speed. In addition, from the discussions on the generation mechanism of the periodic error and high-frequency undulation, some worthwhile references to engineering applications are also derived.

The degree is an important parameter for B-spline. In this paper, as one example of optimal design in mechanism, the optimal design of the cam curve to control the residual vibration of the follower output for an indexing cam mechanism is taken and the effect of the degree of the B-spline to describe the cam curve on the optimization performance is discussed by obtained results.

Removed due to plagiarism. The original was published as follows: Lors, C., Martínez Aldaya, M., Salmon, S., Ponge, J.F., 2006. Use of anavoidance test for the assessment of microbial degradation of PAHs. SoilBiology and Biochemistry 38:2199-2204www.elsevier.com/locate/soilbio

Liquid forging is a new technology of plastic forming. It is a kind of bulk forming process with liquid metal with high-quality and efficiency and it has the characteristics of both die casting and forging. This paper will discuss the liquid forging process, die design, simulation and optimization of liquid forging [1].

In order to improve ZnWO4 photocatalytic activity under visible light, the C, N-codoped ZnWO4 nanoparticles have been successfully synthesized by choosing C3N4 generated from tripolycyanamide pyrolysis as the source of Carbon and Nitrogen and the influence of C3N4 concentration on structural, optical and morphological properties of C, N-codoped ZnWO4 using X-ray diffraction (XRD), UV-visible spectroscopy, scanning electron microscopy (SEM) and photocatalytic decoloration of rhodamine B (RhB) aqueous solution under visible light. It was found that the presence of carbon and nitrogen could not improve the crystallization of ZnWO4 species but could enhance their photoabsorption property in the visible region. The results also showed that the photocatalytic activity of the as-prepared ZnWO4 is higher than that of pure ZnWO4 with the optimum effect occurring at RC3N4 = 9 % (the weight ratio of tripolycyanamide to ZnWO4)

Based on BIOMASS methodology, FEPs analysis and data preparation, the biosphere model for Beishan, China (BIOMOBEIC) for performance assessment on high level radioactive waste(HLW) disposal repository has been developed by utilizing AMBER which is an efficient compartment modeling tool in order to evaluate dose rate to individual due to long-term release of nuclides from the HLW repository. From the result of mathematical simulation, the biosphere dose conversion factors (BDCFs) are obtained which are critical factors for conversion of release rates from the geosphere to individual doses in biosphere assessment and performance assessment.

Introducing the development background of bio-energy in our country,the present situation and trends of international bio-energy research,the bio-energy development path under the constraint of food security,telling the study meaning of bio-energy and food security problem,and doing some study and prospect on this issue to our country. Bio-energy is divided into three generations according to the extractive technology and the use of material.The first generation is based on the sugar and starch to produce alcohol or oil crops to produce bio-diesel.And it is also the bio-energy that has been realized industrialization development.The two generation is based on the cellulose or lignin to produce alcohol,but it is still on the way[1].The third generation start the study of diesel technology using the aquatic micro-algae organisms. At present the main form of the bio-energy is biogas,Boyden production,bio-diesel and fuel alcohol[2]. Because of the huge number of organisms on earth, according to biologists estimate, earth annual growth biological energy volume of about 1400 - 1800 tons ( dry weight ), ten times to the current world total energy consumption, so Bio-energy has wide use value and has great historical significance to take place exhaustible resources such as coal oil and so on.

Phosphomolybdic acid loaded on SiO2 has been prepared as the catalyst by the sol-gel method. The catalysts were evaluated for the oxidative desulfurization of model fuel oil using hydrogen peroxide as an oxidant. Results show that the calcined temperature, Mo/Si molar ratio, catalyst dosage, H2O2 dosage, reaction temperature and reaction time affect the desulfurization rates. The oxidative reactions fit apparent first-order kinetics, and the apparent activation energies of BT and DBT are 51.87 KJ/mol and 25.79 KJ/mol, respectively.

The vibroacoustic phenomena for the slender elastic thin shell filled with water by finite element method is introduced in this paper. The unsymmetric (u, p) variational formulas and finite element procedures are implemented for 3 dimensional structures of vibroacoustic environment based on the displacement field u and the fluid acoustic pressure field p. As illustrated by numerical examples, the longitudinal acoustic pressure eigenmodes will be occurred besides the transverse bendable eigenmodes of the slender shell, nonetheless the eigenvalues and the order of eigenmodes for the fluid acoustic pressure field can only be determined by the flexibility and geometry stiffness of the slender shell.

The aim of naval ship evacuation is to direct crewmembers form the dangerous cabins to mustering station or action station as quickly as possible, when the ship is likely to be attacked or on fire. While evacuating, the crew’s escape routes have to open various watertight doors or airtight doors, which will speed evacuation but it may also degrade the ship’s post-evacuation integrity. In the proposed the multi-objective path program model for warship emergency evacuation, in consideration of the conflict between the minimization of total travel time and the minimization of ship’s integrity. The multi-objective problem was converted into single objective problem by weighted method. The crew speed on each arc depends on the total number of evacuees traversing the arc at roughly the same time. We proposed a heuristic algorithm to solve the multi-objective time-varied escape route planning problem. Finally, a numerical example is presented to show the effectiveness and feasibility of this algorithm.

In order to determine the anti-shock performance of marine gear, dynamic model of gear-rotor-bearing system under external load is established. On the base of Hertz contact theory, the mathematical model of maximum stress response of the gear tooth contact area is developed and the typical shock spectrum was transferred to double peaks and triangle wave to simulate the process of base excitation. By simulating different impact pulse width and acceleration peak value, the programming result is in good agreement with Finite-Element simulation. The study considers that the bearing oil film can absorb impacting load and Information on stress response of gear contact area under external load could offer references for the design of marine gearbox to enhance the resistance to underwater shock damage.

In this paper, a spectral element method (SEM) is applied to simulate the axisymmetric flow in Czochralski crystal growth. The coordinate singularity for 1/r at r=0 is avoided by using the Gauss-Radau type quadrature points for the spatial discretization. The SEM solver is validated by its application to the benchmark problems suggested by Wheeler [1]. The stream function is solved by an artificial Poisson equation with the present method. The results show that it agrees well with available data in the literatures.

The catalysts of HPMo/SiO2 modified with Ce3+ were prepared by the sol-gel method. The catalysts were characterized by FT-IR, XRD, SEM and pore structure parameters and evaluated for the oxidative desulfurization of model fuel using hydrogen peroxide as an oxidant. Results showed that the catalysts kept the Keggin structures and the introduction of CeCl3 promoted the high dispersion of MoO3 over SiO2 and increased the specific surface area of the catalysts. Under the optimal reaction conditions, the desulfurization rate for dibenzothiophene (DBT) and benzothiophene (BT) achieved 98.9% and 43.4%, respectively.

Mesoporous catalysts [HPMo][HTAC]2/SiO2 with different loading amount of [HPMo][HTAC]2 were prepared by sol–gel method. The catalysts were characterized by XRD, FT-IR, SEM and pore structure parameters. The catalytic activity for the oxidative desulfurization of benzothiophene (BT) and dibenzothiophene (DBT) was evaluated using hydrogen peroxide as an oxidant. Results of the charaterization show that the Keggin structures of all the loaded catalysts were kept and [HPMo][HTAC]2 was highly dispersed on the surface of SiO2. The desulfurization rate of the catalyst 20%[HPMo][HTAC]2/SiO2 can be up to 91% for DBT and 75% for BT in 2 h.

The cathode materials 0.3Li2MnO3•0.7LiMnxNixFe(1-2x)/2O2(0.35≤x≤0.5) were synthesized via low-heating solid-state reaction method. The prepared samples were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), thermogravimetric analysis (TG) and differential thermal analysis (DTA), and their electrochemical performances were also investigated here. The FESEM images of samples revealed that the particle of Fe-substituted samples became smaller and size distribution got narrower compared with the materials without Fe-doping. The results showed that electrochemical properties of the material depended on the content of Fe. 0.3Li2MnO3• 0.7LiMn0.4 Ni0.4Fe2O2 maintained 99.5% of the reversible capacity after 60 cycles

According to the complex mining geological condition of Shandong gentle inclined multi-seam mining, Use the three-dimensional finite element numerical analysis software to establish three-dimensional geological model under the different mining working conditions. Taking into account the impact of faults to calculate multi-seam roof strata movement and surface subsidence caused by the different mining working conditions. The level displacement & subsidence distribution curve of the reference point of surface & multi-seam roof strata under the different working conditions is shown. The maximum, minimum settlement, differential settlement and subsidence diagram is shown. And the principal stress, shear stress value of surface & multi-seam roof strata after mining also is shown. The results showed that: little change of the biggest surface subsidence and differential settlement is caused by mining 3101&3102 face or separate 3101 or 3102 face. And the largest subsidence, and the settlement difference of the surface is 520mm, 498mm, 515mm and 59mm, 78mm, 81mm, Respectively. It provides an reference for reasonable, safe, economic for the inclined multi-seam mining under similar conditions.

Hydrophilic poly((poly(ethylene glycol) methyl ether methacrylate) (P(PEGMA)) brushes were grafted from chloromethylated polyethersulfone (CMPES) hollow fiber membrane surface by surface-initiated atom transfer radical polymerization(SI-ATRP) to improve the membrane’s hydrophilic property. The CMPES hollow fiber membrane was prepared by phase inversion process. The benzyl chloride groups on the CMPES membrane surface could afford effective macroinitiators for grafting the well-defined polymer brushes. Attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy confirmed the grafting of P (PEGMA) chains. Field emission scanning electron microscopy (FESEM) was used to characterize the surface morphology of the CMPES membrane and modified membrane. The grafting yield of P (PEGMA) was determined by weight gain measurement. The results showed that the number-average molecular weight (Mn) of P (PEGMA) increased with the polymerization time. It was found that the grafting of P (PEGMA) brought higher pure water flux, improved water uptake ratio and better anti-protein absorption ability to CMPES membrane after modification.

The non-uniformity distribution of UV light intensity in the imaging plane of integral micro-Stereolithography (µSL) System will induces serious distortion of object in building process, and the building accuracy of the SL system can not be assured. To obtain uniformity distribution of UV light intensity, experimental investigations were performed to research the relationship of UV light intensity with position (x,y) in the imaging plane and gray-scale z of the pattern in the integral µSL System. Based on the experiment results, the model of UV light intensity was established with least squares method. According to the model, for a given point in the imaging plane of the µSL system, the UV light intensity can be changed with varying the gray-scale of the pattern. As a result, Uniformity UV light intensity distribution is obtained in the imaging plane, and the difference between maximum and minimum value of UV light intensity is 0.06µW/cm2. The uniformity UV light intensity distribution provides a foundation for building accurate microstructures with the µSL system.