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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.

Many plants accumulate silicon in the form of phytoliths (microscopic grains of various shapes).
To date, researchers have accumulated additional material and, in particular, a fairly large number of new types of phytoliths.
A number of researchers believe that living organisms arose as a result of matrix synthesis of key biomolecules and biostructures on inorganic matrices.

The ingredients of stone materials are very complex, and the main component of sewage caused by them is a mixture of water, abrasive dust, slag grinding grain, marble and granite debris.
When annual working days d is300, daily working time t is 8 hours, the required equipment number is 2 block machine and a polishing line and 2 bridge cutting machine.
(2) In the formula: Qsm is sludge produced by block machine. b1 is sawing blade width of block machine, which is 2mm; the number of saw blade  n is 8; the feed speed Vs is value range of 0 ~ 55cm/h; the saw blade spacing d is general scope for 1 ~ 2cm.

In mineral processing process, the vast majority of mineral products contain a large number of moisture[6], the concentrate obtained by gravity concentrate plant and magnetic separation plant also contains a large number of water.
Study on the Classification of Fine Grain Material [J].

Russian companies engaged in three-dimensional printing face a number of problems connected with consumables.
Thus, the analysis of the powders produced by EOS Company has shown that their average diameter amounts to about 25 mcm, and more than 50% of grains of powder are located in the dimensional range of 20 – 30 mcm.
Due to a great number of chemical elements and their compositions, the exact quantitative values of phases are almost impossible to evaluate, therefore, the data on the quantitative estimation of the phase composition are not given in this paper.

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.

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.

The ingots were coarse-grained, and it was possible to extract from them the single-crystals of about 0.4 mm in diameter.
Apparently, decrease of number of the 4е and 4f “dumbbell” sites is the mane reason for increase of the temperature of ferromagnetic ordering in the Tm2Fe19-xMnx and Tm2Fe16, Tm2Fe17, Tm2Fe18, Tm2Fe19 systems as Fe content decreases.
Strengthening of ferromagnetism in these systems with decrease of Fe content should be stipulated mainly by decrease of number of defected 4е “dumbbell” sites which are characterized by strong local negative Fe-Fe exchange interactions.

As a result, a growing number of complex refractory ore resources with the characteristics of low-grade, fine particles and symbiotic complex come into ore dressing and metallurgy industry[1-3].
There is a large number of beach placer reserves in northern Waterfront of Taiwan, between Taitong and Xiu Guluan River mouth.
Mn 0.71 0.39 0.92 MnO Fe 37.36 20.34 48.06 FeO O 31.15 59.20 Total 100.00 Fig. 3 EDS results of analyzed point 1 Table 3 EDS results of analyzed point 2 Element Weight [%] Atomic [%] Compound [%] Chemical formula Mg 1.74 2.37 2.88 MgO Al 1.87 2.31 3.54 Al2O3 Ti 4.88 3.38 8.14 TiO2 V 0.52 0.34 0.93 V2O5 Mn 0.59 0.36 0.76 MnO Fe 65.10 38.72 83.75 FeO O 25.30 52.52 Total 100.00 Fig .4 EDS results of analyzed point 2 Table 4 EDS results of analyzed point 3 Element Weight [%] Atomic [%] Compound [%] Chemical formula Mg 2.19 2.97 3.64 MgO Al 4.02 4.89 1.70 Al2O3 Ti 1.02 0.70 7.59 TiO2 Mn 1.02 0.61 1.32 MnO Fe 66.65 39.25 85.75 FeO O 25.09 51.57 Total 100.00 Fig. 5 EDS results of analyzed point 3 According to the results of elements′ line-by-line scanning (Fig.2 (c,d))and the EDS results of the analyzed point1,2and 3, we can deduce that most metallic minerals have a certain amount of Ti, which illustrates that fine-grained

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].