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CHINA aliuwenyong@126.com,byangpeng_hsr@126.com, cjece 0123@126.com,danyongye@yahoo.com Keywords: Iron tailings; Dry mortar; Comprehension utilization; Proportion design Abstract: This essay is the subject of national eleventh five support schemes: The analysis of key technology on emission reduction and comprehension utilization of solid waste from large iron ore mine (Number:2008BAB32B14).
Introduction This essay is the subject of national eleventh five support schemes: The analysis of key technology on emission reduction and comprehension utilization of solid waste from large iron ore mine (Number:2008BAB32B14).
Stacking density: ρ=1.46×103Kg/m3, fineness modulus: 1.33, chemical analysis refer with Table 1, grain size distribution refer with Table 2.
Table 1 Chemical analysis Component Loss SiO2 Al203 Fe2O3 CaO MgO SO3 Cl- Total Content % 1.96 71.78 4.65 10.70 3.75 4.56 0.84 0.0121 98.25 Table 2 Grain size distribution Range（mm） Grader retained percentage (%) Accumulated retained percentage (%) >4.75 0.4 0.4 2.36~4.75 0.4 0.8 1.18~2.36 2 2.8 0.6~1.18 10 12.8 0.3~0.6 28 40.8 0.15~0.3 26.8 67.6 0.075~0.15 18.8 86.4 <0.075 13.6 100 (2)Cement and its performance analysis The cementing materials are PO42.5 cement made in Heng-sheng-ran Building Material Technology Co., Ltd.

Results and discussion The microstructure of a bulk CF-PFT-PT composite is dense and fine grained.
X-ray microanalysis indicates that ferrite grains are smaller (0.1 – 0.5 mm in diameter), while relaxor grains are larger (0.5-1.5 mm) and show more irregular shapes.
This difference may arise from the presence of ferroelectric grains which restrict domain wall movement at the ferrite-relaxor interphase.
The observed discrepancy between the antiferromagnetic transition temperature of the pure PFT relaxor at low temperature of 9 K and the position of a relevant maximum in FC curve of the bulk CF-PFT-PT composite may arise from the influence of PbTiO3, which forms a solid solution with Pb(Fe1/2Ta1/2)O3, from the presence of adjacent ferrite grains and a strong impact of the preparation method and the history of a composite sample.
The elucidation how the number of the layers and the ratio of their thicknesses influence the magnetoelectric coupling needs further investigation.

(8) This inequality means that the best approximation of the solution is obtained when the following integral is minimum : ( )** : min.dVσ ε Ω =∫ & (9) The sample is divided into N number of shells.
The initial texture before deformation was not completely random (see in [6]), so it was discretized to 500 grain orientations with the technique of Tόth and Van Houtte [7] to represent the initial texture of the material.
Then, a symmetrization of the texture has been carried out leading to 2000 grains: orthotropic symmetry, representing the initial symmetry of the sample due to its pre-processing.
This value was then imposed to each slip system of each grain in the given shell.
After finding the appropriate value of the unknown parameter η, the grain orientations and hardening was updated in each grain and in each shell.

Table 1 Parameter list 1R Wheel external radius, 150mm or indicated otherwise 2R Workpiece external radius, 100mm or indicated otherwise ),( 11 �r Grain initial location ( 110 Rr �� , 
� 20 1 �� ) 2r Position of machining point ( 220 Rr �� ) L Offset between wheel and workpiece axes, 1RL = or indicated otherwise 1� Wheel angular speed (= 12 n�
, +: CCW, -: CW) 2� Workpiece angular speed (= 22 n�
, +: CCW, -: CW) f Infeed rate t Grinding time � Workpiece tilt around X-axis Workpiece tilt around Y-axis In a cartesian coordinate system that the origin is fixed at the center of the work, the vector (t)2r or the three position components [ )(),(),( tztytx ] of a cutting edge (abrasive grain) is specified as [2] Grinding wheel Workpiece ���� n2 n1 Y X Z Grinding wheel Workpiece ���� n2 n1 Y X Z � � Grain t1� 2r 1r C Workpiece t2� O X Y Grinding Wheel L 1R )(),( tytx )(),( ttyttx �+�+ 2r� 2R s� Grain t1�t1� 2r2r 1r1r
deviation from the base profile) if it is well controlled. ���� � ��� ���� ��� � �� ��� :�O O ;�O O ���� � ��� ���� ��� � �� ��� :�O O ;�O O <�O O ���� ��� � �� ��� ���� ����� ���� ����� � :�O O <�O O ���� ��� � �� ��� ���� ����� ���� ����� � :�O O ���� � ��� ���� � ��� ���� ���� � :�O O ;�O O <�O O ���� � ��� ���� � ��� ���� ���� � :�O O ;�O O <�O O (a) o o 0,1.0 =±= � ���� � ��� ���� ��� � �� ��� :�O O ;�O O ���� � ��� ���� ��� � �� ��� :�O O ;�O O ���� ��� � �� ��� ���� ����� � ���� ��� :�O O <�O O o 1.0�= o 1.0= ���� ��� � �� ��� ���� ����� � ���� ��� :�O O <�O O o 1.0�= o 1.0= ���� � ��� ���� � ��� ���� � ��� :�O O ;�O O <�O O ���� � ��� ���� � ��� ���� � ��� :�O O ;�O O <�O O (b) o o 1.0,0 ±== � Fig.3 Tilting effect on profile form When the cutting edge changes its position from )(t2r to )( tt �+2r at a short period of t� , the grain
When a cup-type wheel is used, the cutting path density )( 2rd at a specific area of the workpiece is therefore stated as 22 22 0 2 2 2 lim)( drrdsm rr sm rd t �= �� �� = �
 
 , or 1 1 2 1 2 2 ( ) 2 R r m ds D r dr r dr
 = � , (5) where m is the number of cutting path created by a single cutting edge.

As it is defined in numerous references, elastic strains are generated to accommodate the plastic strain incompatibilities in a material between grains and layers, and are dependent upon the applied loads.
For the sin 2ψ method, where a number of d-spacings are measured, stresses are calculated from an equation derived from Hooke's law for isotropic, homogeneous, fine grain materials, ψ is the angle subtended by the bisector of the incident and diffracted beam and the surface normal, and φ is the direction of stress measurement
The above model applies for isotropic, fine grain and homogeneous materials.
If the grains are coarse or there is a crystallographic texture or a steep gradient at the surface, precautions on how to use the technique should be taken; different remedies are suggested to adapt the sin 2ψ method to these special cases [3].
The grains in the material deform in 3 directions because of the effect of the surrounding material that is deforming under the effect of the applied load.

However, the majority of ventilated facade systems offered for implementation are characterized by a number of significant defects.
Studies on determining the optimum performance of modifiers (slag, superplasticizing admixture C-3 and accelerating agent AS) in order to avoid the random variation of the average density of foam concrete were carried out using fine grained concrete.
The class of strength of fine grained concrete with slag, С-3 (0.6%) and accelerating agent AS (0.07-0.09%) at the age of 28 days after steam curing and hardening in pumping unit PU is increased from В22.5 (control composition) up to В55.
Strength of fine grained concrete at this KM consumption and hardening in PU at the age of 28 days is 89.1 MPa, and after steam curing at the age of 1 and 28 days, respectively, 68.8 and 87.2 MPa, exceeding the strength of the control composition by more than in 2.7 times.
The investigated types of chemical and mineral modifiers with established optimum performance with the use of fine grained concrete were used in cellular concrete with the aim to improve its structure and properties (Table 1).

The fractured surface exhibited well crystallized grains with an average grain size of a few hundred nanometers.
The density of all samples was above 97%, and the grain size after hot pressing was slightly increased by SEM.
A coarsening and grain growth was observed for the Cu2.995Co0.005SbSe4 powder hot-pressed as shown in Fig. 2.
In addition, the potential energy barrier could scatter low-energy carriers and increased the average energy of carriers because of the small grain size and the increase number of interfaces after ball milling.

They are often affected by internal oxidation too, in the matrix or in grain boundaries [1].
The constitutive phases can be clearly evidenced since their average atomic numbers are sensibly different.
In a same grain, these new carbides exhibit a same orientation.
They may coexist with the initial grain boundary carbides which have not yet disappeared and which have a more compact shape.
Carbon lost by decomposition of the initial grain boundary carbides disappears, without any doubt being oxidised into CO or CO2 gases.

The armature acts at a macroscopic level (on grain aggragation), and not at level of individual grains [4].
Due to the aggregation of smaller particles into bigger ones, one of the early effects of adding lime is to make the grains coarser.
This procedure was suitable for fine grained soils.
The number of blows (drops) necessary to close the gap in the soil specimen for a length of 13mm was recorded.
The relationship between the moisture content and the number of blows was plotted on a semi-logarithmic chart with the percentage moisture content as ordinate on the linear scale and the number of blows as abscissa on the logarithmic scale and the best line of fit drawn through the resulting points.

Cell numbers began increasing again within 10 days of reaching temperatures that would facilitate mesophilic growth being restored.
Cell numbers were reduced with the sudden temperature increase, and did not recover over the remainder of the experiment.
Mineralogical characteristics, including sulfide grade, grain size and liberation (accessibility of sulfide minerals to lixiviant and microorganisms) are key parameters in heap bioleaching.
Cell number (˜) and redox potential (g) in the columns for ore A (C) and ore B (D).
During this period, both the solution redox potential and cell numbers decreased (Fig. 1D).