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EDX analysis in Fig.4 indicated the grain “a“ is YSZ and grain “b“ is Al2O3.
The micrograph(A) showed the size of Al2O3 grains were larger than YSZ grains.
The size distribution of Al2O3 grains almost were 1~3μm.
The distribution of grains in the micrographs was not obvious and grains linked closely.
We also thank the New Star Technology Plan of Beijing under grant number 2007A080.

This suggests that a higher number of passes may induce the breakdown and dispersion of further chip boundaries and achieve ODS.
This is due to a combination of factors, including the refined grain size imparted during ECAP [14], the refined grain size imparted during machining (a SPD process in itself [15]), and finally the brittle oxide present within the chip boundaries.
The microstructure consists of fine α grains (light phase) and β grains (dark phase) located at the triple points of the α grains, and is typical of Ti-6Al-4V subjected to a relatively low temperature recrystallization heat treatment step.
Closer inspection of the β grains reveals the existence of fine α lamella in the β matrix, or the Widmanstätten structure, indicating that the so-called ‘β’ grains are in fact ‘transformed β’.
Langdon, Principles of equal-channel angular pressing as a processing tool for grain refinement, Prog.

A number of 0-D approaches are known to render some results in demonstrating the feasibility of the solar tower concept, or in unsteady simulation of transient phases in rocket engines.
In the case of the RE suppose that such an elongated engine, with a tubular solid propellant grain in the thrust chamber or a small, slender liquid propellant engine and a contoured expansion nozzle, experiences a starting or mid-cruise transient.
To be more specific, let first refer to the thermodynamic behavior of the solid propellant RE, presenting the geometry of the chamber area and the propellant grain depicted in Fig. 1.
On a local scale however, the fact that the burning on the grain surface usually progresses on its lateral area, inner in the present case, involves a continuous process of mixing of the evading gases from the combustion surface Aa with the main flow in the channel core, in a two-dimensional manner.
head wall Nozzle profile A(x) x-Axis t-Axis O Star-shaped grain channel A(x,t) Chamber/nozzle interface Computational observed volume υ(t) Propellant grain Fig. 1: Assumed slender solid propellant rocket motor.

Waterjet cutting, water jet, abrasive grains, surface roughness, circular milling, taper of a cylindrical part.
Despite the positive technological capabilities of waterjet cutting of materials, there are number of shortcomings in the quality of manufacturing parts made of chromium-nickel alloys [4,9-11].
In other words, abrasive grains, together with water, when penetrating into the body of the workpiece, create additional pressure to some extent on the surface of the workpiece due to the difficulty of chips exiting, which leads to an expansion of the contact zone, increasing the dimensions of the upper deviation.
Preliminary studies have shown that during waterjet cutting the contour of cylindrical workpieces, the sizes, shapes and types of abrasive grains can be varied, which will significantly reduce the deviation of the edges of the cut parts.
During waterjet cutting of cylindrical workpieces, the end contour of the edge part at a depth of ±0.3-0.4 mm is formed by errors; it has been found that abrasive grains, leaving traces of impact on the end face, form a certain degree of surface deviations, which requires further mechanical processing in order to form the end surface within the required limits of the part drawing. 2.

With increasing calcination temperature, the fiber diameters decreased until the temperature up to 900 °C the morphology change from cylinder to square or rectangular shape grains.
In the last decades, a large number of researches have been carried out on lead-free piezoelectric ceramics to substitute for the widely used PZT for high performance applications [3].
When calcination temperature was increased to 900 °C, the morphology of the nanofibers changes to square- or rectangular shaped grains and some large abnormal grains with grain size between 0.2 -0.6 mm.

Analysis of variance abuout the sadiment size in Jiuyuangou and Tuwei River Watershed’s silt dam Li li1,2, a,Weiying Sun2, b,QI He2, c,Xinxin Hou2,d (1 Xi,an University of technology, Xian, 710048, China；2Yellow River Institute of Hydraulic Research , Zhengzhou, 450003, China) aemail:hnlily168@163.com, bemail: 16691232@qq.com, cemail: 287364315@qq.com, demail: xinxin_hou@qq.com Keywords: Silt dam; Jiuyuan gou Watershed; Tuwei River Watershed; Coarse sediment; granularmetric analysis Abstract: Analysising twenty-one silt dams in Jiuyuangou watershed and thirty-six silt dams in Tuwei River Watershed drilling hole sampling’s data, Jiuyuan gou Watershed’s silt dams in coarse sand size mainly concentrated in the 0.05mm,Tuwei River Watershed’s silt dams in coarse sand size mainly concentrated in the 0.05mm～0.10mm,The dam upstream sand size is generally larger than the dam downstream, sorting depends on sediment dam on the dam upstream tosand size, dam upstream sediment grain size is
Table 1 The analysis results of different stratum area in Wuding River and Tuwei River Watershed[1] The name of river Catchment area （km2） Percentage of drainage area（%） Loess Sandwind Bedrock Wuding River 30216 56.7 31.8 11.5 Tuwei River 3294 24.6 62.7 12.7 Table 2 The analysis results of the average suspended particle is actually measured in Hydrological station about Wuding River and Tuwei River Watershed[2] The name of river The name of Hydrological station More than a grain size sediment weight percentage（%） Average particle size （mm） Median particle size （mm） 0.05mm 0.10mm 0.25mm 0.50mm Wuding River Baijiachuan 32.8 8.3 2.3 0.5 0.048 0.034 Tuwei River Gaojiachuan 54.4 28.5 14.3 4.5 0.102 0.035 Analysis results about sediment’s size in the Jiuyuangou watershed’s the silt dam.According to the particle size analysis results, the silt dams that the average particle size’s in front of the dam is less than the dam tail in Jiuyuangou Watershed are seventeen,81% of
the total number; the silt dams that the average particle size’s in front of the dam is close to the dam tail are three, 15% of the total number; the silt dams that the average particle size’s in front of the dam staggeres distribution in the dam tail and intermediate are one,5% of the total number.
Figure 1 Average sediment grading curve in front of the dam and the dam tail about Jiuyuangou Watershed Analysis results about sediment’s size in the Tuwei River watershed’s the silt dam.According to the particle size analysis results, the silt dams that the average particle size’s in front of the dam is less than the dam tail in Tuwei River Watershed are twenty-eight,77% of the total number; the silt dams that the average particle size’s in front of the dam is close to the dam tail are five, 14% of the total number; the silt dams that the average particle size’s in front of the dam is bigger than the dam tail are three, 9% of the total number.

Of special interest are HCP polycrystals with the ratio с/а < 1.633, which suggests a greater number of slip systems.
Strain hardening would occur in ‘soft’ grains oriented for prismatic slip, which would cause a fast increase in the dislocation density within the same grains and formation of a great number of low-angle boundaries.
Complexity of the integration of lattice dislocations in such boundaries and their subsequent annihilation due to the limited number of possible dislocation reactions between <а> and <с+а> dislocations, causes accumulation of dislocations within the cells (fragments).
The lack of independent slip systems imposes a constraint on the reorientation of grain fragments.
Popova, Grain structure, geometrically necessary dislocations and second-phase particles in polycrystals of micro- and mesolevels, Physi.

The test results show that the accumulative plastic strains increase with rising tempeature, increasing the vibration numbers and dynamic stress amplitude.
The soil used in the current study was obtained from the embankment along the Qinghai-Tibet Railway in China.The grain-size distributions of the materials are presented in Fig. 2.
Grain size distribution of clay from Qinghai-Tibet railway.
When the dynamic stess amplitude is 2.9MPa, the relationship curves of accumulated strain and vibration numbers is stable type at -7 °C, but is the failure type at -3 °C.
As is shown in Fig.7(a) , when the number of load cycle is same, the accumulative plastic strain decrease with increasing frequency.

The microstructure of the two alloys at different annealing temperatures for 1 hour is shown in the Fig. 1.The grains are elongated along the rolling direction and turned into a fibrous tissue by cold rolling.
The observable difference between Fig. 1(b) and (d) with the same anneal temperature and holding time is likely to be due to the different concentration of Mn in two alloys; while alloy with 0.7 wt.% Mn is not fully recrystallized with a small quantity fibrous tissue , the alloy without Mn is fully recrystallized with equilateral grains.
The original grains are broken into blocks by cold-rolling and a large number of dislocations are formed in the blocks and around their boundaries.
Because the energy of Mn in the grain is higher than that of Mn in the dislocation and around the grain boundaries, Mn tends to gather around the grain boundary and dislocation.
During the annealing process, the activation energy of Mn diffusion is higher than grain boundary diffusion, resulting a slower diffusion rate of Mn than grain boundary.

The grains at the HAZ are slightly coarser than the grains at the TMAZ.
The thermal exposure had caused the grains to grow.
The relation between grain size and the mechanical properties (strength and hardness) can be expressed by the Hall–Petch equation [8].
Eq. 2 shows that smaller grain size diameter results in higher strength of the material.
This was due to the grain refinement effect resulted from the stirring action at high rotational speed.