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The viscosities are strong functions of temperature, density and grain-size, all of which change dramatically in the sintering process.
To determine the parameters in the grain-growth law, a series of sintering tests have to be interrupted to measure the grain size at different sintering times, which is yet another expensive and time consuming exercise.
(19) Du and Cocks also used the following law for grain-growth [21]: ( ) ( ) 3 0 0 2/3 1 d d d d D = − & &
Grain growth was not considered and the initial grain-size was set as 300.d = µm.
The same accuracy was obtained by Kiani throughout the sintering process (i.e. not only at t=1000s) and for the case with grain-growth.

δ13C in soil and maize analysis The maize leaf samples of the number four plant in each row were taken at 70 days after planting from the third leaf from top position, the third leaf from bottom position and the middle leaf between the top and the bottom positions.
Leucaena hedgerow, whereas in of maize-chili strip intercropping without hedgerow grain yield decreased from 8.55 to 8.06 t ha-1.
Including hedgerows significantly reduced grain yield from the control plot of sole cropping.
The decrease in δ13C values of leaf was consistent to grain yield increase in Figure 8.
This confirmed by no significance in grain yield in each maize row along slope position of the control plot (sole cropping).

The quality of the kerf depends on a large number of input parameters, so that their selection becomes a current problem of real technological interest.
So, it was decided to choose a fine (100 mesh #) and ultra-fine (200 mesh #) abrasive grain size, g, for increasing the probability to obtain a good surface finish.
An approximate average variance of residuals was estimated by the relationship: MSres = m N – li=1NRzi - Rzest i2= mN – l i=1Nei2 = 35.520 , (4) where m = 2 is the number of replicas, N = 32 is the experimental volume, and l = 7 is the number of coefficients in Eq. 2.
Delamination is present only in some of the samples, corresponding to run numbers 3, 15, 32 (Table 2).
It turned out that three input parameters have a significant influence on Rz roughness parameter, the most important influence being exerted by the traverse speed, followed by the focusing tube diameter and then, by the abrasive grain size.

This fine-grained material contains high amounts of zinc and iron as well as significant amounts of potentially toxic elements such as lead, cadmium and chromium.
Table 1 Chemical composition of dust subjected to pelletizing, % Sample number Fe total Zn Pb S SiO2 Al2O3 CaO MnO Cr2O3 P2O5 MgO 1 42,28 10,85 3,11 0,59 6,13 1,45 5,30 5,32 0,37 0,17 3,52 2 34,57 20,0 2,35 0,65 6,26 1,27 7,27 4,32 0,38 0,16 2,77 3 40,31 3,0 0,2 2,17 5,30 8,40 12,30 4,54 0,26 0,32 2,86 Dust processing as pellets Dust collected in bags filters batteries with, fitted out the cleaning system of modernized furnace (EBT) is subject to pelletizing process.
Size grading of dust The dust that is formed in EAF has the following size grading: Table 2 Dust size grading Grain size, mm 0 – 5 > 5 – 10 > 10 – 20 > 20 - 40 > 40 Weight, % 71,9 8,3 6,0 7,5 6,3 When the pelletizing machine bucket is full with dust, the disk that made pellets by wetting dust with water about 10%, starts.
To determine the number of recycling that can be subjected dust until the zinc content increase over 25%, the percentage needed the economic extraction of zinc in the non-ferrous industry by Waltz process, a balance has been made.

But this composite powders are non-self-fluxing with higher melting point, so the pool surface is lack of protection and cladding power is higher, that will lead to a considerable number of base melting and a greater coating dilution[11,12].
When the laser power is 1.8kW, there are a large number of depressions and tubercles on the coating surface.
a A B substrate bright area coating c b 20μm 5μm 100μm Fig.3 Boundary micrograph (a), surface micrograph (b) and SEM image (c) of composite coatings Fig.3(a), Fig.3(b) and Fig.3 (c) show the coating mainly consists of two-phase microstructure, with a larger number of uniformity staggered fine dendrites, which are shown as the grain A in Fig.3 (c), and a small number of intergranular phase distributed continuously around the dendrites, shown as the grain B in Fig.3 (c).
On the one hand，this may be caused by the extremely fine grains or microstructure, and the compressive stress in coating in laser process; On the other hand, B, Si, Fe and other elements contained in raw ingredients , can cause different levels of solid solution strengthening effect when rapid solidification and solid-state transformation occur.
The two-phase microstructure of the coating consists mainly of large number NiAl and less Ni3Al, with NiAl being uniformity and staggered fine dendrites surrounded continuously by Ni3Al, and the atom ratios of Ni: Al: Fe: Si in NiAl and Ni3Al are 54: 39: 2: 5 and 70: 21: 3: 6

After 1 hour, large number of small crystal grains (≤0.5μm) covers the surface intensively.
After 2 hours, small crystal grains are ≤0.8μm and the number is increasing.
After 3 hours, small crystal grains are almost ≤0.8μm and the number is increasing.
Higher pH makes both homogeneous and heterogeneous nucleation rate bigger, so the number of crystals is more, but size is smaller.
The second kind is small number and large.

By the SEM pictures we can see that there are some spots on the membrane surface which deposited by fine grains, EPS and SMP.
（12） In this equation, ds means diameter of membrane module, nf means the number of fiber bundle, df means diameter of outer fiber.
Fig.4 Photos of SEM According to the photos of SEM, there are some spots which deposited by fine grains, EPS and SMP on the membrane surface.
Conclusions (1) According to compared with the test data and three models,the Ostwald model was chose to been the best model to express the apparent viscosity of sludge,and the expression is,in this expression,,,the aeration area(ds means diameter of membrane module,nf means the number of fiber bundle, df means diameter of outer fiber)
Elmaleh, Dimensionless number for the steady-state flux of cross-flow microfiltration and ultrafiltration with gas sparging, Chem.

Let be the grain diameter for a granulated material with the regular structure.
Let be number of cycle.
Index describes the number of crack advances ( is the critical number of crack advances when construction is divided into parts).
The specific (effective) grain size for these steels is in the range 0.02 – 0.05 mm.
The obtained effective diameter at fracture can be associated with the parent austenitic grain diameter of steels [24].

In particular, B2O3 enhances grain growth and inhibits densification by promoting coarsening at temperatures below 1800°C.
It is known that mechanical and vibratory milling of powders enhanced densification with the increased surface area and also increased the number of point defects near the surface of the particles, enhancing the driving force for densification by grain boundary diffusion.
The microstructure contained both equiaxed and slightly elongated ZrB2 grains with an average grain size of 6µm.
Reduction of grain growth was attributed to lower HP temperatures and reduced starting particle sizes.
The enhanced densification was believed to be plastic flow of TiCx grains present in the composite at the processing temperature while improved mechanical properties (strength and fracture toughness) of the 4.8:1 compositions were attributed to the platelet morphology of TiB2 grains.

Taking a ratio of Eq. (4) for two tests in different thickness sand moulded channels, numbered 1 and 2, gives (5) The spiral results are all reduced to the value that would have been obtained if the spiral tests had the sections of the geometry used in the present work (8 ´ 10 mm2).
Figure 9 shows the grain structure of the A356 alloy in the region of the tip of the fluidity spirals.
Finer and homogeneous grain structure with no columnar grains are revealed throughout, with distributed microshrinkage.
Typical grain structure of AlSi7Mg alloy at the tip of the fluidity spiral.
Ferraro, Effect of grain refinement and cooling rate on the microstructure and mechanical properties of secondary Al-Si-Cu alloys, J.