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Submerged biological filter:by constructed, reach, The undercurrent of type of bacteria filter ,in experiment hole arrangement form up filler, Water can form filter recoil contact up(effective solving the problem of biological membrane).Artificial wetland packing:the first broken brick zone composed of big particle diameter lightweight porous brick, particle size:5~6mm, 50cm long; the second sand zone is common river sand, particle size:1~2 mm; the third silt mixed zone (the ratio of soil to sand for 1:9), soil is cultivated soil, sand is 1~2mm common river sand, the loading height: 40cm first broken brick:, 20mm covering soil layer, 40cm sand bed, 20mm covering soil layer, 60cm soil thickness, 60 cm last broken brick.The material of filter including: sand, brick rubble, structure and grain diameter: supporting layer 20cm, grain diameter 2~3cm: 10cm thickness, 5~10cm grain diameter under of broken brick; 20cm thickness, 0.9~2mm grain diameter up of broken brick; sand layer:20cm thickness
, 0.9~1mm grain diameter.
In studies reported, artificial wetland on CODcr removing is generally higher, when sewage flows through the aeration tank and undercurrent type biological filter, using the strong oxidative degradation ability of high concentration of biofilm quantity on filter material purificates sewage fast, it is a biological oxidation degradation process, at the same time, when sewage flows, the filter material is compaction state, the advantage of the characteristics of smaller particle filter material and biological flocculation of biological membrane, retaining a large number of suspended solids in wastewater.The CODcr content in the influent is 39.92 mg/L(Fig.5), the removal rate of CODcr is 76.61~86.53% in the artificial wetland system, the removal rate of CODcr is 89.15~93.64% in the whole system, the CODcr content of the outfluent is 18.89~32.56 mg/L, up to the surface water environment quality standard GB3838-2002, and below 40 mg/L of Ⅴ class standard.

The microstructure of the samples subjected to water quenching, as seen in Fig. 2a and 2b, are found to produce martensite structure like acicular needles combined with β phase grain.
Both materials show similar grain size and is around 280 µm calculated by the intercept method.
The quenched samples exhibited fatigue strength slightly higher compared to the furnace cooling sample with a decreasing number of cycles at increased stress.
The fracture mode of FC alloy was predominantly transgranular with some dimples within grains according to phase distribution (Fig. 6d).
Is not clear in which exact phase initiation crack fatigue starts, but it can be presumed that a large grain size contributes to the reduced fatigue strength of both alloys.

We report on the investigation of domain imaging in [001] oriented BaTiO3 giant grains studied by means of secondary electron microscopy.
The detailed description of the preparation method for the giant grains [10] used here and of the procedure for in situ characterization of domain switching [9] as well as of the piezoresponse method [11] for unambiguously characterization of domains in scanning force microscopy has been given elsewhere.
Results and discussion SE-SEM micrographs of [001] oriented BaTiO3 giant grain recorded with a secondary electron signal at different energy of primary electrons Epr and irradiation time are shown in Fig. 1.
Typical SE-SEM micrographs of a [001] oriented BaTiO3 giant grain showing polarization contrast of 90°-ac-domain walls and the progressive effect of the electron beam on the domain contrast when increasing Epr form a) 5 keV to b) 20 keV, t2 and b) 20 keV, t3, where t3>t2.
The SE yield δSE, which is the number of secondary electrons released on an average from the target per incident primary electron and collected in an asymmetric arrangement.

Cracks are passing through the internal part of the grains since under cold temperatures the grains boundaries are more consistent than mere grains Cold laps- it refers to defects due to collision of prematurely solidified metal flows.
Confusion or exchange of the alloys in categorizing, the melt pollution, improper execution of eutectic or grains refinement is the cause of these defects.
The emerging oxide does not dissolve in the aluminium melt or any of its alloys which, with its stirring in the molten metal, causes the emergence of separate particles, the oxide inclusions.Oxide inclusions are structural defects formed by microscopic particles Al2O3 which are distributed along the borders of dendritic grains.
Conclusion The occurrence of defects in the casting is subject to a number of factors such as: a type of the cast alloy and its metallurgical processing, a die casting machine, a die casting mold structure, an gating system, a venting and cooling system of a mold, adjusted technological parameters of casting and last but not least the attendance of die casting machine.

Roughness (black) and columnar grain size (blue) of ZnO films estimated by AFM.
AFM measurements showed a strong reduction of the columnar grains size (from 900 nm per films deposited in pure Ar to around 400 nm for those deposited in Ar/H2 atmosphere) and a similar reduction of the RMS roughness.
The observed hardness maximum can be therefore explained by the reduction of the grains size, probably due to the Hall-Petch behavior [18].
On the other hand, the coatings deposited in Ar/H2 atmosphere showed similar grain size, while the mechanical properties strongly change.
It is clear that the reduction of IAr/IHα ratio leads to an increase of porosity This is probably caused by the interaction of the reactive hydrogen species (Hα) produced during the sputtering process which remove some oxygen from the depositing film, increasing the number of oxygen vacancies and changing the density of material.

Introduction Thermal barrier coating (TBC) have been found an increasing number of application in protecting high-temperature metallic components of gas turbines by reducing the temperature of substrates [1,2].
While the the surface of YSZ is densely composed of two types of grains (larger irregular gains and small equiaxed grains) which may be corresponding to the two two different phases in YSZ (tetragonal phase and monoclinic phase)[13].
Abnormal large grains with size above 1μm are clearly observed.
LaYSZ exhibits porous surface with homogeous grain size distribution after heat treatment at 1400˚C for 100h, while YSZ shows dense surface with abnormal large grains are clearly observed.

This is attributed to the uniform and fine grain structure and the lack of shear bands.
It was found that lube ratio and the number of lubricant layers (thickness) have less effect on the tendency to form an acceptable panel void of splits.
As ZEK100 alloy contains 0.2-0.5 wt.% zirconium and 0.12-0.22% of rare earth elements, the alloy exhibits fine and uniform microstructure, composed mainly of Alpha-Mg grains and eutectic phase in the grain boundaries.
After warm forming, the alloy still remains the fine structure without significant grain growth.
The good formability of ZEK 100 alloy may be attributed to its homogeneous grain structure.

SrBi2Ta2O9 belongs to the Aurivillius layered-perovskite family with a general formula of (Bi2O2)2+(Am-1BmO3m+1)2, where A and B are the metal ions and m indicates the number of the perovskite-like units in the nominal formula of ABO3 between the (Bi2O2) 2+ layers along the c-axis in the orthorhombic structure.
However, as seen in Fig.3 (b), no distinct columnar structure was observed and the film had no apparent grain boundaries.
The film was dense and homogeneous with rod-like grains.
The emphasis on lowering the surface roughness and enhancing packing density and grain growth of SBT films would be improved in our later studies.
The ferroelectric measurements of the remanent polarization and the coercive field the films indicate the key to success of this process are optimizing microstructure such as lowering the surface roughness, enhancing packing density and enlarging grain size.

In as-prepared composite, the peaks of attapulgite (110) was obvious, and can glimpse the diffraction peaks of anatase TiO2, but the peak is relatively wide, indicating that the TiO2 composite grain size is relatively small.
When it reaches 800˚C a small number of diffraction peaks corresponding to rutile TiO2 appears, as a result, crystal transition temperature of TiO2 in the composite was significantly higher [14].
Masanori Hirano et.al.[15] found that the critical grain size ranging from the general anatase to rutile phase transition is about 10~16nm, that is to say, the grains in this range can maintain anatase status, and phase transition from anatase to rutile will occur when larger than this size, this conclusion can well explain the experimental results; From 850˚C to 900˚C rutile TiO2 gradually increased, simultaneously, at 900˚C the TiO2 anatase diffraction peak at 25.55°(2θ), the diffraction peak move 0.35° to the right shift when compared with 850˚C, This may be due to smaller spacing of TiO2 layer at high temperature. 2.2 Effect of heat treatment on the patterns of TiO2/ATP Composite （a） （b） （c） Fig.3 TEM pictures for nano-TiO2 and nano-TiO2/ATP composite(a) Nano-TiO2 at 450˚C(b) Nano-TiO2/ATP Composite at 450˚C(c) Nano-TiO2/ATP Composite at 850˚C From Fig.3(a) Nano-TiO2 polygonal crystal structure can be seen at 450˚C, grain size is about 10 ~ 30nm, but the reunion is serious
, a lot of nano-particles congregate together; Fibrous crystal structure can be found in Fig.3(b), which is consistent with the perfect crystal characteristics of attapulgite, while we can see many small nanoparticles on the surface, XRD pattern shows the load TiO2 on the ATP surface From the perspective of grain size, the TiO2 in the composite is about several nanometers to tens of nanometers, which is probably due to large surface area and strong adsorption of ATP that resist the formation and growth of TiO2 crystal in the composite.

As the dimensions of a particle decreases, the number of surface atoms steadily grows, as compared to that of the inner ones.
In-situ vacuum deposition experiments of Barna et al. taught us that coalescence of touching crystallites could be either complete (resulting in a single crystal grain) or incomplete (preserving a grain boundary within the coalesced polycrystalline particle) [5].
We can predict from this analogy, that the coalescence process must be an incomplete coalescence, since the second phase (the stabilizer) pins the movement of the grain boundaries within the newly coalesced polycrystalline particles.
Right: Formation of huge (micrometer sized) polycrystalline particles in the sol (Bright field image), when the particle growth is not limited (in order to obtain large-grained powder for pigment applications).
Analogies have been observed between the growth mode of these nanoparticles in the sol and the growth mode of grains in vacuum deposited thin films.