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Extrusion process and mould design for contact finger by stamping machine is introduced in this paper. The structural design of the die is simple and practical, the productivity is improved significantly, the material consumption is reduced accordingly , the quality of products is very good and the production cost is low.

Aimed at the present domestic problems in the forging process of claw pole, such as insufficient corner filling, excessive forming force and short life of dies. On the basis of the analyzing in the claw pole, a new process named the closed hot die forging, direct extrusion process of claw pole is constituted. The numerical simulation using DEFORM-3D and the special mould are used in the forging experiment in order to check the new process. The results show that, new technology has greatly reduced the forming force, thereby reducing the production processes and improving the life of dies for mass production.

In order to guarantee the reliability and security of reclaiming water, research on the removal efficiency of the environmental endocrine chemicals (EDCs) --the Phthalate Esters (PAEs) in conventional secondary activated sludge and wastewater reclamation and reuse process was undergoing at Harbin wastewater treatment plant (WWTP). The wastewater samples were colleted from every unit effluent of WWTP. The results showed that contamination of EDCs were presented in municipal wastewater at Harbin and the concentrations of the four PAEs were 21.01μg/L for Di-n-butyl Phthalate (DBP); 9.63μg/L for Di-n-octyl Phthalate (DnOP); 4.56μg/L for Diethyl Phthalate (DEP); 1.96μg/L for Dimethyl Phthalate (DMP) respectively in the influent. The conventional activated sludge has good removal efficiencies performance on DMP, DEP and DBP. With the increasing of molecular weight and branch chains of PAEs contaminations, the removal rate of the four PAEs in the conventional activated sludge process decreased from 99.82%(DMP)，90.60%(DEP)，90.10%(DBP) to the only 45.13% removal rate for DnOP, which was mostly removed from primary treatment but no from secondary activated sludge process; Coagulation-air flotation plus filtration process was not a feasible way to remove PAEs from reclaiming treatment units.

A new uranium-containing silicotungstate A-β-Na14[Na2(UO2)2(SiW9O34)2]·43H2O (1) was synthesized in an aqueous solution. The compound was characterized by elemental analysis and infrared spectra analysis. A single-crystal X-ray analysis was carried out on crystal (1) which crystallizes in triclinic system, space group p ī, with a = 13.386 Å, b = 13.506 Å, c = 16.183 Å, α = 85.337o, β = 73.608o γ = 64.833o and Z = 1. Polyanion (1) consists of two A-β-SiW9 units which sandwich two uranium and two sodium ions, leading to a Keggin-type sandwich structure. The photoluminescent spectrum of (1) shows typical emission features of uranyl compounds.

New types of ecologically benign surfactants with sugar as head groups (N-alkylglucosamides) have been described, namely, N-octylglucosamides (NOGA), N-dodecylglucosamides (NDGA), N-cetylglucosamides (NCGA). N-alkylglucosamides were characterized by Fourier transform infrared spectroscopy (FTIR) and1H Nuclear Magnetic Resonance (1HNMR) respectively. N-alkylglucosamides was immobilized onto the surface of PPNWF by using Glycidyl methacrylate (GMA) as the linking agent. The chemical structure and composition of the modified PPNWF surface were analyzed by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and X-ray photoelectron spectroscopy (XPS). The surface properties were investigated by water contact angle. The water contact angles of the modified PPNWF decreased from 111° to 73°. The hemocompatibility of the modified PPNWF was evaluated by platelet adhesion. The number of platelets adhering to the modified surface was more dramatically reduced than that of the virgin surface. The results indicate that the modified surface of PPNWF by N-alkylglucosamides was a facile approach to construct biocompatible surface.

The development of agricultural mechanization not only has to consider its development speed, but also should coordinate with economic development. Therefore, taking economic development as the independent variable, and agricultural mechanization development as the dependent variable, the nonlinear relationship model was established. Then, on the basis of forecasting GDP which on behalf of the economic development level, the demands of agricultural mechanization for economic development was predicted. Given the limitations of single forecast model, the nonlinear combination forecast models based on BP neural network was established to forecast the development relationship between economic and agricultural mechanization. The predicted results show that the fitting mean absolute percentage error is 2.61% for the relationship of economic development with agricultural mechanization development, and the fitting mean absolute percentage error is 2.14% for the GDP, which are all far less than the fitting error of traditional forecast models. The validation forecast was carried out; the results show that the combined forecast model can effectively improve the prediction accuracy. The demand of agricultural mechanization for economic development was forecasted from 2012 to 2020 in China using the established nonlinear combined forecast model based on BP neural network. The results show that the demand of total power of agricultural machinery for economic will be 1232298.2 MW by 2015 and 1560579.6 MW by 2020.

Study on the fractural mechanism of thin sheet metals focuses on how to efficiently fracture and recycle the scrapped vehicles and electrical equipments. By using the experimental fracture mechanics, the failure mode was studied for 10F rimmed steel sheets to be crushed and recycled. In-plane mode I, out-plane mixed mode I /III and mode III fracture tests were conducted under different loading angles. The effects and contributions of mixed mode crack extensions for 10F rimmed steel sheets were analyzed and some sensitive fractural factors were studied. The experimental results show that pure mode III is most viable to fracture the thin sheet 10F rimmed steels.

In order to improve beer sterilization effect of wastewater treatment, reduce the heat load of the sterilization wastewater on subsequent water treatment processes. In this paper, through optimizing transformation developed micro-flocculation -membrane treatment processes. Screening for the identification of inorganic polymeric aluminum ferric chloride flocculants as the technology. The best dosage was 15mg / L, the field test to verify the craft beer sterilized wastewater treatment effect. The results show that, micro flocculation membrane treatment process in the water after treatment of COD and turbidity removal rate is respectively 76% and 98%. To illustrate the use of this technology in the treatment of beer sterilizing water without two stage filtration, can effectively recycling sterilized wastewater.

In this paper, the fracture process of WCp/Cu functionally graded materials(FGMs) was investigated. The used materials were fabricated by powder metallurgy using tungsten carbide(WC) particles and copper(Cu) matrix, and had functionally graded layers. In order to investigate the fracture process of the FGM, three-point-bending tests of rectangular specimens were carried out. From the results, it can be seen that the bending performance of FGM structures with increasing WC content from head layer to the bottom layer excels that of FGM structures with decreasing WC content in three-point-bending tests.

The paper introduced the source and harmfulness of heavy metal pollution in water environment and summarized the applications of the chemical method, physiochemical method and biological method in heavy metal pollution of sudden emergency accident. Meanwhile, the heavy metal pollution emergency processing technology of rivers, lakes and other water bodies were elaborated and the emergency engineering technology of heavy metal pollution in rivers and lakes were analyzed. Finally, the application of bioremediation on heavy metal pollution caused by sudden emergency accident was prospected.

This article describes the simulation method of water temperature and the model classification of water quality in lakes and reservoirs, and classic model of ecosystem dynamics of lakes and reservoirs - BA model from the water quality parameters of the relationship between two aspects of the basic equations are introduced. On this basis, establish the eutrophication of ecological models of lakes and reservoirs.

In this paper, taken Landsat5/TM and SPOT5 image which was imaging in the close time as data source, the land-use map were obtained, respectively. In order to do some researches about LUCC and ecological effect, soil loss and landscape pattern metrics were selected as ecological index by corresponding counting methods. By analysis and contrast, it showed that soil loss obtained by Landsat5/TM and SPOT5 image has little difference, and the average soil erosion modulus are 181.54 t/(km2•a) and 190.17 t/(km2•a), respectively. The erosion area in different erosion classification does not appear distinct difference. By the landscape pattern metrics value, it showed that the difference of MSI, PAFRAC, CONTAG and SHDI in Landsat5/TM and SPOT5 is only between 0.07 and 0.3, and the difference of LPI and AI was higher than above 3 types of index. But in a word, there were no big difference for all the index.

Forests are drawing people’s more and more attention as the main parts of carbon sequestration. Therefore, making full use of the advantage in forests of Heilongjiang province has great significance in both ecology and economy. This paper aims at raising ideas about constructing the system of carbon finance and related issues combined with the potential of carbon sequestration on the basis of the property to be cleared.

The copper matrix composites reinforced by different WCP volume fraction were fabricated via Vacuum Hot-pressed Sintering technique. The tensile performance and fracture behavior of WCP/Cu composites were studied by uniaxial tension tests and the fracture surfaces were examined by SEM. The test results of mechanical properties show that the WCP/Cu composites exhibit obvious improvement of tensile property comparing with that of the matrix. The fracture surface morphology indicate a trend that the fracture of WCP/Cu composites changes from debonding to cleavage with the increase of the WCP volume fraction.

The aim of this study is to fabricate WCp/Cu functionally graded materials (FGMs) and test its properties. Vacuum Hot-pressed Sintering technique is used to develop the graded WC particle reinforced Cu matrix composite. Using powder layering technique, a multi-layered WCp/Cu FGM have been prepared successfully. Scanning electron microscopy is used for microstructural analysis. Microscopic observations display that the microstructure of WCp/Cu FGM distribute gradually, and have no visible macroscopic interface. The mechanical properties of WCp/Cu functionally graded materials have been investigated, including Vickers's hardness, Young’s modulus and Tensile strength. Experimental results show that the properties of WCp/Cu FGM strongly depend on compositional variation.

By analyzing the rheological behavior and stress to the metal in cross-axle during a radial extrusion with floating-die, establishing a computational model of rigid-perfectly plastic and the stressing model similar to the forward extrusion, and introducing a simple forward extrusion calculation into a complicated radial extrusion calculation, a new calculation for radial extrusion is proposed, then the axial clamping force on female-die and other load parameters are calculated. Through verifying the result by Deform-3D numerical simulation, the formula proposed in this paper is approved to be of a relatively small error and a high accuracy, which can be applied to various calculations of forward extrusion model.

Blends of polycarbonate (PC) and highly branched polystyrene (HBPS) were prepared by melt blending. The steady rheological behavior of them was determined using a capillary rheometer, furthermore, the effect of shear rate, temperature and the blend component on the viscosity of the blends was discussed. The results showed that all the blends exhibit the nature of the pseudo-plastic fluids, and the viscosity of them decreases dramatically with the increase of temperature and does slightly with the increase of shear rate. At a fixed shear stress, the viscosity of the blends is decreased with the increase of the HBPS content. Microstructure studies using SEM showed that all the blends are characteristic of a two-phase morphology, with spherical droplets of the minor HBPS phase dispersed in the continuous PC phase.

A new measurement of friction coefficient which is more applicable to overload extrusion technology is proposed in this paper. It determines the friction coefficient of overload plastic forming by firstly determining the load mutation of friction by a floating die experimental device. It is proved in this experiment that the friction coefficient in extrusion process can be precisely determined and the effectiveness of lubricating can be evaluated objectively by this new method which is easier to understand and master than the theory that determines the friction coefficient by ring upsetting.

In this paper, based on the finite element analysis platform ANSYS, the stress field of particle reinforced metal matrix composites (PRMMC) caused by current impulse has been simulated. The cube cell model and multi-particle random distribution cell model are used in this simulation. The current field, temperature field and stress field of PRMMC caused by current impulse are given. The influence of material character of PRMMC, number or volume fraction of the particles in cell model, particles shape and distance on those fields is analyzed.

In order to provide theory basis and experimental evidence for optimizing milling parameters, the cutting force prediction models for milling of Ti6Al4V with uncoated cemented carbide tool were built based on single factor method. The significances of the cutting force prediction models were checked. The effects of milling speed, feed per tooth, milling depth and milling width on cutting forces were also studied. The results show that the built prediction models can be applied effectively to predict the cutting forces in milling of Ti6Al4V in the experiment parameters range. Milling depth has highly obvious influence on cutting forces among these milling parameters. The cutting forces decrease with the milling speed increasing, and increase with feed per tooth, milling depth and milling width.