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However SLM process is defined by a large number of parameters: laser power, scanning speed, layer thickness, point distance, exposure time, hatch space, stripe width, scanning strategy, powder bed temperature, building atmosphere and other), this complicates optimization of SLM process for each new metal or alloy.
SLM process is defined by a large number of parameters.
Attallah, The influence of the laser scan strategy on grain structure and cracking behavior in SLM powder-bed fabricated nickel superalloy, Journal of Alloys and Compounds. 615 (2014) 338-347

Several test cycles of 24 hours were carried out (the number of test cycles was limited by a weight loss of one of the samples equal to 0.07 g.), after that the samples were removed from the installation, and their wear resistance was evaluated by weight loss, and the microstructures of metals were examined by metallographic analysis using the OLYMPUS BX51M microscope at magnifications of 100, 500 and 1000 times in order to investigate the causes of wear of the samples.
The microstructure of the sample of steel 15 with a deposited layer X10, x100: a - crack from the fusion zone; b - crack from the surface of the weld metal Metallographic studies showed the presence of a significant number of cracks in the deposited metal, which propagate both from the zone of fusion of the deposited metal with the base (Fig. 2) and from the working surface, which was probably the reason for the significant mass loss of the sample.
Summary Practical recommendations for optimizing the primary structure are the following: it is necessary to strive to reduce dendritic parameters in massive workpieces, for example, by blocking the process of coarsening of dendritic branches with surface-active substances, and grinding primary grains by selecting heterophasic modifiers.

The substrates are formed by equiaxial alpha phase grains (pure titanium) or alpha-beta phase (Ti64 alloy).
The lower wear loss in case of Ti64 at lower number of cycles (9.72 x 105) is probably due to the hardness difference in both materials.
For samples tested at high number of cycles (7.76 x 106 cycles), the wear loss improvement was almost 10-fold for Ti and 100-fold for Ti64 bearings.

In this study the grain size and other line broadening factors besides plastic work are taken to be insignificant across the sample and FWHM is considered to be a good indicator of plastic work.
This may be because for a given cutting rate the number of passes per second is larger for small radii.
This suggests that the heat build-up in the tool has an insignificant effect on residual stress; although it may be that the number of passes per second that is important.

granular material lime replacemen 2×20cm two-kinds ash subgrade 6cm coarse graded asphalt concrete 4cm medium grain of asphalt concrete 1550 cm 20cm three-kinds ash subgrade Fig. 6: The recommendation of road construction Table 5 On-site detecting of the compaction, deflection and unconfined compressive strength mark pile on-site detecting 7d unconfined compressive strength [MPa] deflection /[0.01mm] compaction degree[%] K0+040 3.06 10 98.8 K0+060 2.97 8 99.8 K0+080 3.17 9 97.0 K0+100 3.03 10 97.4 K0+120 3.12 13 97.7 K0+140 3.35 13 98.2 According to the information in the Table 5, the 7d unconfined compressive strength meet the 3.0 [MPa] constructing standard, the representative deflection 19.92[0.01mm] is lower than the controlled deflection 32.5[0.01mm], and the compaction degree is higher than the 97% quality standard.
Acknowledgements This work was financially supported by the national natural science fund， the number of funded project is 51078242, and the ‘Young and Middle –Aged Specialist of the Nation with Prominent Contribution’, the number is 2012921047.

Biofuels will be produced from biomass resources, including corn grains and lignocellulosic biomass (such as agricultural residues, forestry wastes, waste paper, and energy crops)[1,2].
Viscosity of the cellulosic preparations was determined by British Standard Methods for determination of limiting viscosity number of cellulose in dilute solutions, Part 1.
It should be noted that a small number of xyloses (5.41%) were still present in the cellulosic fraction C3.

A large proportion of the Chinese phosphate reserves are sedimentary deposits (collophanite) that contained a considerable amount of silica and magnesium, and the rock grain and the dissemination are fine [2-3].
Furthermore, the maximum two concentrate efficiency were obtained at test points number 8 and 5, where concentrate efficiency were 33.80% and 33.58%, respectively.
Table 3 showed, the concentrate indexes between test points number 8 and 5 were approximate.

They reported that Page model was found to agree with the experimental data with less than 1.4% of RMSE while effective moisture diffusivity, Deff value of millet is found to be approximately three times lower than that of ragi (food grain) and corn.
These parameters may be expressed as: N i=1 x2 = Σ (MRexp,i – MRpre,i) N – P (1) 1 Σ (MRexp,i – MRpre,i)2 1/2 N RMSE = N i=1 (2) MRexp,i – MRpre,i MRexp,i 100 N P = (3) (MRexp,i – MRpre,i) Residuals = (4) where MRexp,i and MRpre,i are the i experimental and predicted moisture ratios, respectively. the number of observations is N, and the number of constants is p.

(2)Coarse aggregate: coarse aggregate used in the test is gravel. 5 ~ 16mm and 16 ~ 25mm two kinds of grain size gravel mixed, blending ratio was 40%, 60%.
Table 4-1 The result of different amount of polypropylene fibers Group number The amount of polypropylene fibers/kg Slump（mm） Extension degree（mm） Description of workability K1 0 215 470 Overall slump,poor cohesion K2 0.6 200 390 Landslides,poor cohesion K3 0.8 215 430 Overall slump, good overall performance K4 1.0 210 420 Overall slump, good overall performance K5 1.2 225 460 Overall slump, good overall performance As shown in Table 4-1,from K1 to K5 ,if only ensure the volume of powder paste, concrete’s cohesion is poor. the water retention and mobility barely meet the requirements, And the overall performance of workability is poor.After adding different amounts of polypropylene fiber, concrete’s mobility reduced, cohesion and water retention improved.Therefore, the mobility can be ensure by appropriately improving the amount of Superplasticizer in the experiment .From K1 to K5,the amount of Superplasticizer
When the incorporation of polypropylene fibers above 0.8% ,the workability of Manufactured sand concrete can be ensured with corresponding Superplasticizer. 4.2 The impact of polypropylene fiber to low-intensity Manufactured sand concrete on Compressive strength Table 4-3 Effect of Superplasticizer on compressive strength Group number 28-day strength 56-day strength K1 25.00 33.39 K2 24.60 27.58 K3 22.81 31.55 K4 24.03 28.30 K5 23.63 31.12 Fig 4-6 Compressive strength (MPa) As shown in Fig 4-6 and Table 4-3,from K1 to K5,the compressive strength reduced of mechanisms sand concrete which adds different amounts of Polypropylene fibers,but the change is very litter.Consequently, The impact of polypropylene fiber to low-intensity Manufactured sand concrete on Compressive strength is not obvious.

As the grain, oil, cotton production base, Manasi revier basin is one better developed agricultural economy area in Xinjiang.
And the increasing use of pesticides, chemical fertilizers produced a large number of organic phosphorus, and organic nitrogen pollutants, then worsen the deterioration of water quality.
Assess the value loss: loss of the In-kind value may involve loss of a number of different physical types.