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Introduction Nitrogen oxides (NOX) have been considered to be one of main air pollutants,which contribute to photochemical smog, acid rain, ozone depletion and the green house effects [1].The large number of diesel exhaust emissions is an important source of NOx in the atmosphere.Among various methodologies,SCR (Selective Catalytic Reduction) technology has been generally accepted to reduce NOx emissions in diesel exhaust.NOx formed in combustion processes is typically composed of >90% NO,so most research have been focused on the standard SCR to control nitrogen oxides by ammonia or hydrocarbons.In recent years,it has been reported that the fast SCR process has faster reaction rate and high NOx removal efficency than the standard SCR[2,3].It is important to develop the catalysts which are active and selective for the oxidation of NO to NO2, Therefore,in front of the SCR reaction unit,oxidation catalyst can be used to convert ca.50 % of NO to NO2,which can promote the fast SCR reaction
For NO oxidation, some research reported that several different Pt based catalysts are found to be the most active one[4,5,6].In this paper,Pt-based catalysts supported on various supports such as γ-Al2O3, TiO2, ZrO2, CeO2 and Ce0.4Zr0.6O2 have been examined ,the support effects and the optimal Pt loading are investigated. 1.Experimental 1.1 Catalyst preparation Pt-based catalysts were prepared by incipient wetness impregnation.Various metal oxides such as γ-Al2O3, TiO2, ZrO2, CeO2 and Ce0.4Zr0.6O2 were purchased and utilized as a support.The impregnated samples were dried overnight at 353K,and calcined at 473K for 1h and then calcined at 773K for 3h.The materials were then pressed into pieces, smashed and sieved to obtain grains of size 40 to 60 mesh. 1.2 Catalyst tests The activity of these catalysts was measured in a fixed bed quartz reactor (6 mm I.D.).The reaction temperature was detected by a thermocouple that inserted into the catalyst bed and controlled by a temperature controller.The
Figure.2 Effect of Pt loading on NO oxidation activity over the Pt/γ-Al2O3 catalysts Table.1 BET surface area of catalysts number sample BET m2·g-1 1 1 wt%Pt/TiO2 86.4 2 1 wt%Pt/ZrO2 5.4 3 1 wt%Pt/CeO2 76.2 4 1 wt%Pt/Ce0.4Zr0.6O2 48.1 5 0.25 wt%Pt/γ-Al2O3 213.4 6 0.5 wt%Pt/γ-Al2O3 212.6 7 1 wt%Pt/γ-Al2O3 185.7 8 1.25 wt%Pt/γ-Al2O3 198.4 9 1.5 wt%Pt/γ-Al2O3 209.6 Figure.3 X-ray diffraction patterns of the Pt/g-Al2O3 catalysts Conclusions In this paper,Pt-based catalysts supported on various supports such as γ-Al2O3, TiO2, ZrO2, CeO2 and Ce0.4Zr0.6O2 have been examined.

The company of Kebelco and Guhe Electic [1~2]did a lot of research about the die material and speed of rotary die; Rotarescu[3] gived a method of theoritical process analysis, which covered the process-zone geometry, lubrication condition at the contact area between spinning ring and balls,number of balls and entering angle.Zhang analyed the folding defect caused by the gap between copper tubes and plug[4].Jiang analyed the forming mechanism by using thin-wall tublar parts[5~6].
Table 1 Tooth profile parameters for the inner-grooved plug Specification Addendum angle (°) Outer diameter （mm） Tooth height (mm) Groove number Addendum fillet （mm） φ9.52×0.27 30 10.62 0.165 70 0.05 The specification of inner-grooved copper tube analyed in this paper has the features of so many grooves and narrow cogging.The folding defect appeared frequently during forming process.
Discussions Inner groove forming The actual and simulation inner groove can be seen in Fig. 4a, 4b respectively.Form the Fig.4a it can be seen that grains of copper tube were extruded and elongated when balls spun close to the coggings of grooved plug.

Adding ultrasonic aid to hot-dip aluminizing can make the crystal grain of plating coat smaller and make the structure of plating coat evener and purer [5].
Acknowledgments The work described in this paper is supported by National Natural Science Foundation (Project number: 51005140), Natural Science Foundation of Shandong Province (Project number: ZR2010EQ037) and Young Teacher Development Support Fund of Shandong University of Technology.

The bulk density and grain size of the sintered sample was 6.08 g/cm3 and approximately 0.2 µm (Fig 1), respectively.
When the monoclinic fraction increased by aging test, the peak position at maximum of the 460 cm -1 band shifted towards higher wave numbers (Figure 2 (c)).
Fig.2 Typical Raman spectra of Zirconia: a)Tetragonal Zirconia, b)Transformed Zirconia (tetragonal + monoclinic) c) Schematic image of peak shift at 460cm -1 as a function of phase transformation a) b) Intensity (a.u.) 800 600 400 200 Wave number (cm-1) c) Fig 1.

Table 2 Formulations of specimens % Raw material Serial number of specimens 1# 2# 3# 4# White corundum Aggregate 51 51 51 51 ≤0.043 mm 10 8 6 4 Si-Fe ≤0.043 mm 2 4 6 8 Zirconium-Corundum 20 20 20 20 Carbon 3.5 3.5 3.5 3.5 Additive 13.5 13.5 13.5 13.5 The apparent porosity, volume density, compression strength, resistance to oxidation, high temperature bending strength（1400°C, 2h）of specimens were tested according to GB/T 2997-2000, GB/T 5072-2008, GB/T 13244-1991 and GB/T 13243-1991.
Table 3 Physical properties of specimens Performance Serial number of specimens 1 2 3 4 Apparent porosity(%) N2-flowing 1.4 1.2 0.9 1.2 CO atmosphere 3.1 3.0 2.9 5.3 Volume density(g·cm-3) N2-flowing 3.36 3.39 3.41 3.39 CO-flowing atmosphere 3.33 3.35 3.37 3.32 Compression strength (Mpa) N2-flowing 140 162 206 171 CO-flowing atmosphere 125 154 178 157 High temperature rupture strength(MPa,1400℃,2h) N2-flowing 16.86 18.34 22.90 20.25 CO-flowing atmosphere 9.61 9.64 10.85 10.86 Practical decarburized depth(mm) N2-flowing 1.92 1.66 0.73 1.45 CO-flowing atmosphere 1.86 1.62 1.29 1.48 From the above results, it is obviously that the performance of slide gate sintered in N2-flowing atmosphere is better than firing in CO-flowing atmosphere,the best material is the specimens3 which was added 6wt% Si-Fe in N2-flowing atmosphere.
The experiment accounted for that: a few Si-Fe reacted to create Si3N4,there is nothing of reaction in the central section of white granule such as B, here Fe:Si=1:1; Si-Fe joined the reaction and created Si3N4 in the edge of white granu such as A, here Fe:Si=3:1, Ti may be the impurity of the raw material.While Si3N4 was found in the edge of this white grain.

Mengcheng County is one of the major grain producing area in Anhui Province, The main agricultural products of it are quality wheat, soybean, potato, and so on.
The national standard soil samples (GSS-1, GSS-2) were put in the soil sample analysis process for quality control, the number of repeat analysis of samples was 10% to 15%.
The increase of these heavy metals content, especially Pb, Hg, Ni, As, was widely considered to be caused by the increase in vehicle exhaust emissions, large-scale use of pesticides, garbage pollution to soil, sewage irrigation, applying a large number of superphosphate, mining activity ect[8,9], but this remained to be discussed further.

Introduction A large number of nodes and critical parts of modern mechanisms operate under high wear and corrosion cyclic loading.
Grain pearlite and ferrite are randomly arranged relative to each other [4].
Scratches become less deep, the number of dark areas is reduced and the wear area is reduced.

A large number of vacancies, grain boundary defects and crystalline phase transition are introduced, promoting interface atomic diffusion and improving the solid solubility of the reinforcement in the matrix.
There could be a number of possible reasons: including the small amount of CNTs used, the well dispersed CNTs within the matrix, unfavorable strain/CNTs effect that reduces CNT peak intensity, and the amorphization of CNTs, and so couldn’t appear [4-5].

The iteration number n is a parameter governs particles shape uniformity; particles can be made more uniform by increasing iteration number, here use default value n = 5.
Étude numérique des matériaux granulaires à grains polyédriques: rhéologie quasi-statique, dynamique vibratoire, application au procédé de bourrage du ballast[D]. 2007 [7]Normes françaises. 1996.

Thus, in order to efficiently control the particle size of prepared powder and significantly reduce the temperature of preparation of the compound, a number of chemical routes using all kinds of precursors, for example co-precipitation[6-8], sol-gel, hydrothermal and colloid emulsion technique, have been developed as alternatives to the conventional solid state reaction of mixed oxides.
Based on XRD analysis, the powder was examined for its morphology and grain size using a field emission scanning electron microscopy (Model JEOL JSM-7600F, FEI Co., Japan).
The gel fired at 550℃ in air atmosphere consists of the mixed phases of Mg5Nb4O15 and Mg4Nb2O9 precursors, which can be matched with JCPDS file numbers 20-0681 and 38-1459, respectively.