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Oversize solids in the fluid are retained, but the separation is not complete; solids will be contaminated with some fluid and filtrate will contain fine particles (depending on the pore number)[3].The hollow fiber membrane filtration modules were selected as they offered substantially high packing density around 9000 m2m-3 as compared to packing density of around 30-500 m2m-3 offered by the plate and frame or tubular membrane format[4].
They are fine-grained and plastic in nature.
The microstructure indicates that the powders in green body distribute compactly and also the grains are connected by polymeric networks [11], which contribute to distribution of porosity in the samples.

A significant number of individual intermetallic compound particles has been analysed by electron diffraction in TEM.
The cells grow equiaxially and the advancing eutectic solid-liquid interface limits the growth of the columnar Al4Cr epitaxial grains.
During remelting at higher speeds, undercooling is higher and nucleation of eutectic Al7Cr/α-Al cells occurs, that grow equiaxially in the liquid ahead of the columnar interface, thus limiting the growth of the Al4Cr columnar grains.

In all experiments, the repetition rates f = 30 kHz and the number of pulses ni = 1 item was left unchanged.
The scratches with sufficiently clear relief formed by the movement of individual diamond grains are highlighted.
The chaotic state of these defects on the surface of ceramics is determined by the random nature of form and arrangement of grains in the diamond wheel.

., its model number is DG1025/18.2-II4, and it belongs to subcritical boilers.
Most often, big secondarily recrystallized grains can be observed, too.
The cooling process after straightening is a normalization process, the metal near the outer surface of pipe wall generates the transition from austenite to pearlite, and inevitably, normalized structure of fine crystal grain will be produced.

In this study, the equivalent diameter ( eqD ) and shape factor ( F ) of primary particles are calculated using the following equations [3]: N A D N N N eq ∑== 1 /4 π (1) N AP F N N N N∑== 1 2 4/ π (2) Where NA and NP are the area and perimeter of a particle respectively, and N is the number of particles. 4.
The equivalent particle diameter and the corresponding intercept particle size were very close to each other as shown in Fig.3, which indicates that the primary solid particles obtained by the RBRM process is close to spherical. 0 20 40 60 80 0 5 10 15 20 25 30 Equivalent diameter Mean intercept length Frequency Grain size (μ m) Fig.3 The Equivalent diameter and corresponding intercept size of the primary α-Al particles in the RBRM process, a shear rate of 740s-1 at 873K for 8s The microstructure-processing relationship of different shear rate and average particle size at the identical solid fraction and shear time is shown in Fig.4.
Fig.4 The relationship of the shear rate and average particle size of A357 alloy at the identical solid fraction and shear time ( 52.0=sf , shear time is 8s) 2 0 0 3 0 0 4 0 0 5 0 0 6 0 0 7 0 0 8 0 0 9 0 0 3 5 4 0 4 5 5 0 5 5 6 0 6 5 Average particle size /μ m S h e a r ra te /s-1 Table 2 Processing conditions and the microstructural properties of the rheocasting A357 alloy Shear time /s Solid fraction / sf Shear rate /s-1 Average grain size /µm 8 0.52 772 42 8 0.52 630 45 8 0.52 472 48 8 0.52 315 60 4.2 The fluid flow characteristics of the slurry in the RBRM The fluid flow characteristics of the SSM slurry inside the RBRM are complex.

There are number of hazardous wastes used in stabilization/solidification (S/S) technique.
Additives pH CEC EC Gs Grain Size (%) Chemical Analysis (meq/100g) (mS/cm) Sand Silt Clay SiO2 Al2O3 Fe2O3 CaO MgO P2O3 K2O SO3 LoI CO2 Lime 12,60 16,43 6.29 2,45 5 75 20 2,72 0,37 0,25 63,88 4,00 0,01 0.06 0.02 27,5 10,52 Cement 12,63 21,74 4.97 3,19 6 58 36 20,35 5,19 3,34 64,56 1,52 0,07 0.70 2.04 1,3 4,86 Zeolite 8,20 165,17 2.09 2,63 2 74 24 71,39 13,30 0.94 2.74 0,71 0,03 3.69 0.01 6,25 0,96 Na-Bentonite 9,50 90,22 2,69 2,60 - 12 88 59,49 18,06 4,14 3,72 2,42 0,11 0,91 0,01 8,02 1,31 Natural Soil 8,14 15,22 2,54 2,56 7 63 30 65,36 14,29 4,31 1,20 1,14 0,09 1,47 0,02 7,43 1,45 CEC: Cation Exchange Capacity; EC: Electrical Conductivity; Gs: Specific Gravity; LoI: Loss on Ignition Experimental Results and Discussion Backfill Materials: Unconfined compression strength (UCS), permeability, leachate test, California Bearing Ratio (CBR), freezing and thawing tests are most popular indicator of stabilization efficiency.
Technical specifications of CCW concrete blocks (after 28 days curing) Parameter Description Size 300 x 200 x 150 mm Compressive strength 40-50 kg/cm 2 Capillarity 4,85 10-6 cm 2/s Water absorption after 24 hours Less than 6 % by weight of block Mix Proportion 1:7 (1 part cement:7 parts sum graded CCTW) Density 1900 kg/m 3 Grain Size Distributions for Concrete Block (%) 4.8-8.0 mm CCTW 2.0-4.8 mm CCTW 0.4-2.0 mm CCTW Crushed Aggregates 0.2 mm Sand 10 % 20 % 20 % %35 15 % Improving Expansive Soil Materials: Relationship between the free swelling percent and swelling pressure are shown in Figure 3.

The effects of alloying elements such as Mo, Sn, Zr, Nb and working-rates, solid solution and aging treatment on the mechanical properties and microstructure of nearβtype biomedical Ti alloys based on Ti-Nb-Zr system were investigated. . 2 Experimental procedures 7 kinds of nearβTi alloy were designed which Mo equivalences (Moeq) ranged from 3.6~10.2 and numbered 3#~9# separately. 0 grade Ti sponge, pure Zr bar (4×2mm, 99.7wt%), pure Sn bar (5×2mm, 99.9wt%), pure Mo powder and Nb53Ti47 intermediate alloy were used as raw materials.
Thus the aging leads to dispersion strengthening and fine grain strengthening of near β alloys.
After solid solution and aging treatment (STA), The βMS or α' start to dissolve and then transform to large quantities of finer secondary α phase (αs) with dot or needle shape in β matrix, which result in dispersion strengthening and fine grain strengthening.

A workpiece is in complete contact with the surface of a super-abrasive grinding wheel, and the cutting force of a single grain on the abrasive wheel becomes smaller while the number of effective cutting edges increases.
References [1] T.Kuriyagawa, K.Nishihara, S.Suzuki, Yinbiao Gou and K.Syoji: Improvement of Machined Surface Quality in Ultra-Precision Plane Honing, Key Engineering Materials, Vols. 238 - 239 (2003), pp.237-242 [2] T.Iyama, K.Shoji, H.Hagiwara : Study on Plane Honing with Fine-grained Grinding Wheel (1st Report, Truing Conditions for a Low Grade Wheel), Journal of the Japan Society for Abrasive Technology(JSAT), Vol.34(1990), No.1, pp.27-32 0 50 100 150 200 250 0 25 50 75 100 125 150 175 200 Inner diameter of truer r t mm Difference between min and max of contact length mm/rev R t=225mm R t=200mm R t=175mm R t=150mm R t=125mm Figure 10 The influence of truer shape upon flatness of grinding wheel surface

So, a number of surface modification techniques have been developed to satisfy the requirements, such as laser cladding, plasma spraying and Tungsten Inert Gas (TIG) cladding.
Li et al. [3] reported that the microstructure of the laser cladding Ni-based alloy (Ni-15.1B-14.4Cr-7.5Si-3.1C-1.0Fe) is composed of blocky CrB type chromium carbon borides, orthorhombic structured Cr7C3 type dendritic carbides, cellular-dendritic γ-Ni solid solution, different interdendritic eutectics and amorphous phase along grain boundaries.
As a result of hard phase precipitation and grain refining strengthening, the microhardness of the coatings with addition of CeO2 was increased 40-70 HV compared with that of the coating without CeO2.

So a number of studies were reported on attempts to develop coatings and coating techniques for protecting γ-TiAl [5].
In the lower portion of the coating's outer layer is dense and continuous, but some holes which were formed of vacancy aggregation were observed at the upper portion, as shown by the arrows in Fig.1 (point A), with the formation of coating, active Si diffused toward the substrate while vacancy aggregation diffused in the reverse direction, that the holes were caused by the diffusion of gas atoms gathered together in the vacancy aggregations, which passing through the defect, phase boundary and grain boundary of the upper portion of the coating's layer [9].
Fig.5 Friction coefficients of samples Fig.6 Mass losses of samples in friction （a） Sliding direction （b） Fig.7 Wear surface morphologies of γ-TiAl alloy: (a) In lower magnification; (b) In higher magnification （a） Sliding direction （b） Fatigue crack Fig.8 Wear surface morphologies of coating: (a) In lower magnification; (b) In higher magnification Fig.7 shows the worn surface morphology of the γ-TiAl alloy at different scales, grooves and grain-abrasion characteristics as shown Fig.7(b), which can be observed in the wear track, because of its poor load-carrying properties of γ-TiAl alloy in dry sliding[11], at the same time, TiO2 oxide film formed during the wear process which is brittle, and the film easy to scale off under contact stress, then TiO2 oxide film reformed on exposed surface, and scale off again, so the wear mechanisms are abrasion wear and oxidation wear [12].