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This paper get 8 group sediment samples with different clay content by artificial mixture, test the sediment incipient characteristic under wave action and current action respectively in flume, to find the relationship among incipient condition, median grain size and clay content, and provide reference for project instruction.
Tab.1 Characteristic of test sediment samples Sample number Sand Silt Clay Average median diameter Sorting coefficient Ratio of diameter less than 0.03mm 1# 59.83 38.20 1.97 0.0674 0.264 6.53% 2# 43.12 47.05 9.83 0.0579 0.660 24.80% 3# 32.54 50.16 17.30 0.0439 1.838 42.60% 4# 22.28 56.95 20.77 0.0328 1.997 47.97% 5# 17.75 58.05 24.20 0.0248 2.014 52.43% 6# 15.01 56.39 28.60 0.0195 2.126 56.60% 7# 10.27 54.06 35.67 0.0105 2.336 66.63% 8# 9.12 51.55 39.33 0.0084 2.270 69.90% Test equipment and method Sediment incipient test under current action carried out in the annular flume [2], which the center diameter of 2 m (see Fig. 1), the water velocity can be controlled by variable speed AC motor, and the velocity can be read from a calibrated relational table of the motor speed and velocity.
Test result and analysis Incipient condition can described as the incipient velocity, incipient friction velocity, critical shear stress, critical shields parameter and sand Reynolds number, while the critical shear stress, critical shields parameter and sand Reynolds number can be calculated by Eq.1~Eq.3
（1） （2） （3） Where is the density of water; is the density of silt; is the friction coefficient of wave-current; is the bottom flow velocity under wave-current action; is acceleration of gravity; is the median grain size of silt; is the bottom friction velocity under wave-current action; is kinematic viscosity coefficient. 4.1 Incipient water velocity calculation under current action Under the action of current, the bed surface sediment balance advocated for the cohesive force and the effective gravity, and the force pushing incipient motion advocates to the shear stress of the bed surface.
(3) The wet density of bottom sediment is different while in current action test and in wave action test, in wave action test the wet density is artificial prepared, that is much larger than the natural close-grained wet density in current action test, so the incipient condition under wave action is greater than under current action.

In practice for manipulation of structure formation and mechanical properties of welded joints [5] refractory particles are on purpose introduced in a metal bath for increasing the number of induced crystallization centers that leads to grain refining while hardening.
Then the dendrite structure of deposited metal merges into the polyhedral grain structure of a heat-affected zone.
Structure of fusion border and heat-affected zone; а – sample № 1, b – sample № 2, c – sample № 3, d – sample № 4, e – sample № 5 The first layer (area A) can be described as a polyhedral granular layer with polyhedral grains of austenite.
Dendrite size (1-5 – sample numbers, dark grey – dendrite width, light grey – dendrite thickness) Conclusion: 1.
The layer of polyhedral grains is best seen in sample №3 (Mo density 20 mg per meter of weld).

In sawing, most of the consumed power is transformed into heat, thereby generating possible high temperatures in the sawing zone, which may cause thermal damages to diamond grains such as accelerating the wear of diamond, the abnormal loss of diamond and etc..
For sawing is machining process which depends on the numerous interactions between the diamond grains and the workpiece, therefore it is also an intermittent grinding.
of the intermittent circles, T the intermittent circle which reflects the changing period of moving heat source (T=πde/nvs), vs the sawblade speed, η the blade segment ratio which is the ratio of total segments’ length to total wheel circumference (η =nls/πde), n is the number of segments, ls is the length of segment.
In Fig.2, the shaded area represents the undeformed chip shape based on the movement path of an diamond grain relative to the workpiece.
Based on Fig.2, it can be seen that the unreformed chip thickness has a cycloid distribution along the movement of the diamond grain.

The article describes the basic mechanisms of interaction of the components of the concrete mixture, the analysis of a number of components and conducted comprehensive studies for the formation efflorescence on the surface of products made from various concrete mixtures by vibropressed.
Introduction When choosing the optimal concrete suitable for a large number of different production of building materials, including single products, often pay attention to fine-grained concrete.
(4) - secondary, efflorescence is also dependent on the overall content of the incoherent debris flows, the number and size of the pores in the concrete.
To accurately the determine the qualitative effect of the binder clinker on the mechanism of portioning and leaching of concrete products, additional studies involving a larger number of samples are required.
D., Influence of fine-grained concrete structure on the main technical properties, Concrete Technology. 2 (2013) 16-17

Abnormal grain, which is larger than about 30�, was observed in the general purifying process P1, and the particle size distribution showed the innormal distribution curve and the average grain was large as 7.13�.
In P2 using the hydrocyclone, the number of abnormal grain decreased significantly, and the average grain was 5.55� and smaller than P1, because the abnormal grain is removed by the hydrocyclone.
As shown in Figure 4, the abnormal grain was completely removed, and the uniform plate particle was observed.
The average grain was 3.55�.
When the spray dryer was used, the yield decreased, but the median grain size was uniform at 3.55�, as the slurry density increased.

But fracture of zinc coating has occurred (in Zone a), the cracks distribute along the micropores, and there are Zn grains between the cracks, sediments grow in number obviously at grain boundary.
Fig.9 shows the comparison of grain structures before and after deformation.
It can be concluded from Fig.8(d) and Fig.9 that grain structure change of sample IV is very obvious, it’s long and narrow.
During galvanized sheet stamping, influenced by the forming force and the friction, zinc coating of surface layer first deforms, then microcracks appear at the interface of inclusions, the second phase particles and the substrate or at grain boundary, phase boundary and dislocation pileup area.
(a) Grain structure before deformation (b) Grain structure after deformation Fig.9 Comparison of grain structures before and after deformation 3 Conclusions 1) During galvanized sheet stamping, influenced by the forming force and the friction, zinc coating first loses efficacy, the failure modes are mainly pulverization, exfoliation and fracture.

The thickness of the annual rings and slope of grain were also measured.
Tension force (samples were loaded parallel to the grain) was increased gradually.
Sample failures were caused by reaching the critical tensile stress perpendicular to the grain.
Screws were oriented perpendicular to the grain.
However, as the number of samples is small, the presented results are prone to statistical error.

At the same time, the nucleating agent also has an effect on both the crystal grain structure and the unit cell structure.
This indicates that fumed silica has a significant role in grain refinement of PP.
In contrast, the more fumed silica in grain refinement is not very obvious (Fig. 2e-g).
The nucleating agent has an effect on the crystal grain structure.
Acknowledgements The authors gratefully acknowledge the financial assistance of Science and Technology Department of Heilongjiang Province (Grant Number GC10A108), the Education Department of Heilongjiang Province (Grant Number 11541267) and National Natural Science Foundation Committee of China (Grant Number21206034).

The alloy contains DO19 hexagonal α2 grains ~2.2 µm in grain size uniformly distributed in the ordered BCC β matrix.
To date, there have been a number of reports on the superplastic behavior of Ti3Al based alloys [4-7], confirming that the Ti3Al based alloys exhibited admirable high temperature superplasticity (HTSP) of elongation greater than 1200% [5,7].
From the SEM microgrophs, the grain structure and grain sizes can be roughly revealed.
Assuming that the α2 grains are spherical particles, the average effective grain size of the α2 grains is 2.2 µm.
Grains with equiaxed shape are suitable for grain boundary sliding and would not give rise to pronounced superplastic anisotropy.

The film thickness was controlled by the withdrawal speed and dip number.
The grains are in the range of 1-10 µm.
The same high temperature annealing can partially melt the grains of YBCO, which reduce grain boundaries and produce more homogeneous film.
Some of them are thickness, NiO poisoning and grains, which are the source of high angel grain boundaries that leads to lower the critical current.
Large grains in YBCO are associated with high angle grain boundaries which greatly suppress Jc.