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This stabilization effect was attributed to Ag atoms redistribution as structure defects, increase in the numbers of Cu-Al pairs due to Ag-Al interaction and the Al atoms redistribution around one Cu atom at the sub-lattice of the martensitic crystal.
On ageing, Ag diffusion from bulk to α phase grain boundaries will produce some Agrich precipitates and increase the Al relative fraction available to combine with Cu [4].
So, this stabilization effect may be attributed to Ag atoms redistribution as structure defects, increase in the numbers of Cu-Al pairs due to Ag-Al interaction and the Al atoms redistribution around one Cu atom at the sub-lattice of the martensitic crystal.
This stabilization effect was attributed to Ag atoms redistribution as structure defects, increase in the numbers of Cu-Al pairs due to Ag-Al interaction and the Al atoms redistribution around one Cu atom at the sub-lattice of the martensitic crystal.

Fe is mainly existed with impurities of FeAl3,T1,T2, and so on .When Fe content is slightly higher in the industrial pure aluminum and the content increases, the number, size of impurity phase will be also increased and aggregated distribution along the grain boundary.
They gathered at the grain boundaries and make condensate depression largen and refinement.
It also can change the form of Fe in aluminum alloys to reduce the needle-like grain, increase the spherical crystal[45].
Guan Ke-xiang et al.[46]have studied the rare earth industry to add aluminum and found that Ce with Fe and other impurities can product the high melting point intermetallic compounds in grain boundaries.
It can make rich-Fe impurity phase refinement and stabilize the grain boundary.

Despite obvious valuable properties this material has a number of disadvantages that significantly limits the scope of application.
General information Fireresistance tests, carried by a number of researchers, have shown that UHPC matrix could be additionally hardened under temperature exposure of 150 to 300 ˚C [13-15].
Hence: - if Silica fume consumption at minimum (~ 5%) and Quartz powder consumption at maximum (~30 %) – distance between cement grains increases, lowering the role of pozzolanic reactions in dense structure formation, porosity of the crystalline phase also rises, which cause permeability growth; - if Silica fume consumption at maximum (~25%) and Quartz powder consumption at minimum (~10 %) – distance between cement grains increases due to the composition over-satiation with SF grains, which cause additional flocculation and increase amount of micro-defects under oven heat treatment
[18] Begunov O., Alexandrova O., Solovyov V., Studying of influence of fiber reinforcing at fine-grained concrete applying in transport construction / Begunov et al./ IOP Conference Series Materials Science and Engineering, 90 012016 (doi :10.1088/1755-1315/90/1/012016) (2017) [19] Caijun Shi, A review on ultra-high performance concrete: Part I.

The amount of thrust and the thrust profile, which may be obtained from a specific grain design, is mainly determined by the propellant composition and the manufacturing process that produces the solid propellant.
However, the quality of the finished grain is mainly due to the manufacturing process.
Aluminum has the symbol Al and atomic number 13.

Dissolved elemental impurities can be removed by a number of different processes including boron treatment for some of the transition metals.
A number of methods have been tried both in the laboratory and on an industrial scale to remove impurities from Al melt but only some of them have been successfully commercialized.
Effects of Residual Transition Metal Impurities on Electrical Conductivity & Grain Refinement of EC Grade Aluminum. in TMS Annual Meeting. 1997.
Light Metals 2006 Vol 4: Cast Shop Technology & Recycling - Aluminum, 2006: p. 753-8 [51] Towsey, N., et al., The influence of Grain Refiners on the Efficiency of Ceramic Foam Filters.
Krug, The Effects of Rod Grain Refiners with Dffering Ti/B Ratio on Ceramic Foam Filtration.

So re-used plastic film mulching can improve the ecological environment of cropland in fallow period, reduce the film pollution and increase grain yield.
Introduction The Hetao region of Inner Mongolia is an important grain production bases, the agricultural area is ​​about 654,000 hectares, and area ​​which use plastic film mulching is about 429,000 hectares.
However, every year crop mulching with new film come into being of a large number of film residue, leading to the "white pollution", which make agricultural ecological environment degenerated [5, 6].
Grain yield of re-used film mulching cropland was significantly increased respectively 11.4% and 16.8% than that of the bare field in two years, and compared with the new film mulching, although grain yield decreased respectively 3.3% and 2.6%, the difference wasn’t significantly.

The results showed that changes of PH value has significant effect on the specific gravity of soil grain, the limit moisture content , maximum dry density, and strength characteristics of loess.
Especially with the number of motor vehicle accelerating, the city build expedited and the serious air pollution, acid rain increased [1], the problem of loess contaminated by acid is prominent.
The possible reasons are as follows: with the increase of acid concentration, a large number of cations will change the chemical balance in soil. thickness of adsorbed water will reduce ,the diffusion layer to thin, plasticity of soil are weak, so the liquid, plastic limit and plasticity index will decrease.
In the liquid limit of soil, containing a large number of water molecules, the colloid ion precipitation reduced, it has little effect on the liquid limit.

The resultant overpressurization can create large-scale travelling pressure waves that cause propellant grain fracture and projectile impact loads because of motion and redistribution of propellant bed, even catastrophic failures under high loading density propellant charge conditions [9].
A number of previous studies had conducted to investigate the ignition and flame spreading process associated with anomalous behaviour [9-11].
The igniter chamber where a small quantity of ball powder was burned was sealed by a diaphragm and a multiple nozzle plate from the flow chamber which contains the sample granular propellant grains.
(3) where, kp is permeability of the packed pseupropellant bed, dp is average diameter of the packed pseupropellant grains, u is fluid velocity of flow in the direction of pressure gradient, Lp is the experience coefficient from experiments.

Higher grain scattering noise and beam skewing in thick welds lead to poor signal to noise ratio and distortion of ultrasonic beam.
Chassignole (2003) Modelling the grain orientation of austenitic stainless steel multi pass welds to improve ultrasonic assessment of structural integrity” International Journal of Pressure Vessels and Piping, 80, 77–85 ].
The calculated features of the defects are trained in the neural network classifier with updated weight and optimized number of iterations, and the defects are classified based on their length and width.
This is attributed to the anisotropic behaviour and textured/ coarse grain structure of austenitic stainless weld metal.

As for distribution of normal stresses sх acting along timber grains across bottom edge of beams (Figures 1 and 2), their maximum values depend on the crack length and its location throughout cross-section height.
One-side through crack with length l in each beam was created through artificial thin cutting along the grain of wood to length.
Such method allowed testing one and the same beam with different crack length, and excluding a number of factors affecting values under measurement.
When carrying out experimental study it has been established that for all values of beams cracked as a result of displacement along grains at the crack tip.