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In addition, the obtained powders have smaller grain size (micrometer).
As shown in Table 2, the a, b, and c lattice parameters were found to be nearly constant for the samples indicating that the number of calcination process did not influence much the crystal structure.
Also, both samples show a single step transition implying good grain connectivity and dominance of Y-123 phase [13].
The increase of grain size may due to grain growth as a consequence of multiple calcinations.
The average grain size increased with the multiple calcination compared to the single calcination (~0.3 μm up to ~0.5 μm) due to grain growth.

The metals grains were collected during the experiment and the results were listed in Table 1.
When oxygen content decreased to 100ppm, solder molten can eject successfully and most grains were uniform spheroid.
Table 1 Results of spray under Different Oxygen Content Materials Oxygen Content [ppm] Atmosphere <100 <25 Solder Irregular Grains Uniform Spheroid Grains Uniform Spheroid Grains A2024 Can't Eject Irregular Grains Uniform Spheroid Grains The upper surface of molten was subjected to oxidation when higher oxygen content was inside the crucible.
Since the number of droplets produced was extremely sensitive to the pulse width, the pulse width must be regulated accurately for uniform droplet generation.
The grains were spheroid and the size of grain becomes uniform.

The influence of the reorientation of grains and the change of their shape during deformation is non-negligible in view of reliable subsequent simulations, as, e.g., deep drawing of a cup.
In this study, we apply a method to reduce orientation data of a microstructure to a small number of texture components by using a partitioning technique of the orientation space [6].Representative reduction of texture data For the identification of main texture components obtained from texture measurements, as, e.g., electron backscatter diffraction, the orientation data is mapped into the Euler space.
Fig. 1: Cubic FZs in Φ − ϕ2-plane and box partitioning of one FZ Following the work [4], where a partitioning technique of the orientation space is used to compute correlation functions, the FZ is divided into a discrete number of boxes (Fig. 1(right)).
When an equiaxed morphology of grains is assumed, the tensor P0 is given by P0(C0) = 1 4π ∫ ∥n∥=1 H(C0, n) dn. (13) In equation (13), the tensor H is defined as H = IS(N�(n ⊗ n))IS, N = K−1, K = C0[[n ⊗ n]], (14) where IS is the identity on symmetric second-order tensors.
Due to the assumption of isotropic grain shape, the spin is homogeneously distributed in the polycrystal, so that the macroscopic spin is identically transferred to each of the α = 1, . . . , N single crystals, i.e., ωα = ¯ω.

Establishment of finite element model In this paper, a simulated finite element model based on the cylindrical grinding process of the single grain is established.
When the single grain act on workpiece with a certain speed, complex physical and chemical changes are occurred in the grinding, and workpiece has a non-linear elastic-plastic deformation.
By using UG5.0, a three-dimensional solid figure was drawn for the grinding wheel with the single grain and workpiece, saved as.
It can be found that the heat flow, along grinding contact area, is not growing, but with the wheel rotation, the single grain from start contacting workpiece to cut out parts, results in a special heat flow which shows nonlinear declining law after the first rise.
Acknowledgment This project is supported by the financial support from the Major State Basic Research Development Program of China (“973” Program) (Number: 2009CB724403), Important National Science & Technology Specific Projects (Number: 2009ZX04001-101) and the Fundamental Research Funds for the Central Universities.

The microstructure consists of coarse dendritic grains (see Fig. 1) with shrinkage pores up to 0.5 mm in diameter.
The linear intercept method revealed the average grain size of 3 mm.
Material contains carbide particles and eutectics γ/γ´ mostly along grain boundaries and interdendritic areas.
Results and discussion Fatigue life curves in the representation of the stress amplitude σa at half-life vs. number of cycles to fracture 2Nf are shown in Fig. 3.
Imperfect persistent slip markings (see Fig. 6) were found after cycling with tensile hold times in several grains.

According to the requirements of DL/T5356-2006, Code for coarse-grained soil tests for hydropower and water conservancy engineering, relative density test is apply to the cohesionless coarse-grained soil with free drainage, the maximum diameter of which is 60mm, and fines content of coarse-grained soil less than 0.075mm should not be greater than 12%.
Combined with principle of preparation for coarse-grain soil, this test adopts elimination method to preparation for filter materials II according to different grading curve, including designing up-envelope, down-envelope and center line.
The results of relative density test of filter material II prepared by standard curve are shown in table 1: Table 1: Results of relative density test of filter material II Compound curve Test group number ρdmax（g/cm3） ρdmin（g/cm3） Characteristic particle size Characteristic coefficient Fines content average value average value D60 D30 D15 D10 (Cu) (Cc) S20（%） S10（%） S5（%） Up-envelop 4 2.15 1.61 19 6 3.1 2.4 7.9 0.79 63 44 25 Designed centreline 4 2.07 1.57 27 9 5.0 3.4 7.9 0.88 51 32 15 Down-envelop 4 1.91 1.48 42 14 8.0 6.0 7.0 0.78 39 20 5 Centreline1 2 2.11 1.57 28 8 4.0 2.8 10.0 0.82 51 35 18 Centreline2 2 2.06 1.57 40 13 5.0 3.2 12.5 1.32 40 25 15 Centreline3 2 1.87 1.46 25 12 7.0 5.9 4.2 0.98 51 25 5 In the case of material source grading curve is consistent, the measured value of filter material II filling in jobsite coincided with the above test value, verifying that the test is reliable.
Table 3: Statistics of check the test results Items Experiment method Formula calculation method Difference ρdmax(g/cm3) ρdmin(g/cm3) ρdmax(g/cm3) ρdmin(g/cm3) ρdmax(g/cm3) ρdmin(g/cm3) Maximum value 2.13 1.63 2.13 1.60 0.05 0.03 Minimum value 1.92 1.51 1.91 1.48 -0.04 -0.04 Average value 2.06 1.57 2.06 1.56 0.00 -0.01 Test group number 40 Conclusion and suggestions a) Through the huge amount of contrast tests in this engineering, further validation the ρdmax and the ρdmin of filter material II are closely related to particle size distribution.
Research and application of construction practical technology for earth rock-filling dam [M].Zhengzhou: The Yellow River Water Conservancy Press (2004) (In chinese) [2] SL237-1999 Specification of soil test [S].Beijing: China Water Conservancy and Hydropower Press (1999) (In chinese) [3] DL/T5356-2006 Code for coarse-grained soil tests for hydropower and water conservancy engineering [S].

The hardness and transverse rupture strength of the ultrafine grain sintered body are 93 HRA and 1740 MPa, respectively.
The microhardness of columnar grain Ti(C,N) coating was 1600 kg/mm2.
From inner (close to the substrate) to outer (close to surface), the grain size increased from 0.1 μm to 0.5 μm, and the grain shape transformed from equiaxed to columnar gradually.
The effects of gun pressure, distance between gun and specimen and pulse number on the coating were anlyzed.
Under the best process condition, gun pressure: 0.2 MPa, electromagnetic valve voltage: 1.5 kV, pulse number: >5, the hardness of the coating was 35-45 GPa.

A high-tensile strength steel (JIS-SHY685) with mean grain size of 13µm was used as specimen, which had a thickness of 5 mm, as shown in Fig. 1.
The height of both divergence and receiving slits was 50 µm, and the widths of them were selected for 200, 300, 500 and 1000 µm, respectively, in order to vary the number of crystal grain concerned in diffraction.
As a result of investigating measurement data, it is suitable for the measurement with sufficient accuracy to include more than or equal to 5000 grains of crystal in the measurement gauge volume.
In this case, the gauge volume for strain measurement was 201 x 2295 x 300 µm 3 and the number of crystal grain in the gauge volume was from 7000 to 14000.
The main conclusions are as follows: It is suitable for the measurement with sufficient accuracy to include more than or equal to 5000 grains of crystal in the gauge volume.

Introduction Sedimentary rocks are formed from sediments derived from preexisting rocks that are broken down into individual mineral grains or dissolved into salts by the processes of weathering.
Sedimentary rocks are formed by the initial deposition of detrital grains followed by compaction and diagenesis.
During transport the grains may be modified by mechanical and chemical processes.
The intersect tool calculates the geometric intersection of any number of feature class and feature layers.
[10] Exner, H.E., “Analysis of grain- and particle-size distribution in metallic materials”, Institute of Physical Metalurgy and Metal Review., 159, 25-42,1972.

It can be seen that obvious phenomenon of grain flaking takes place near the worn area of the ZrO2 ceramic.
The micro crack unceasingly extends along grain boundaries during the continuous wear process.
When the extension reaches another pore or defect and forms connectivity, small particles with low bonding strength on grain boundaries will be fallen off from the material and result in grain breaking-off.
The grain flaking and brittle fracture can easily happen under the action of frictional stress and thermal stress.
The cover material is formed mainly by two means: on the one hand, a large number of abrasive dusts have been produced in the friction process.