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In the structure of concrete without additives, structurally coarse hydration products in the form of plates, scales, fibers, needle-shaped crystals are located on the surface of cement grains (Fig. 1,b).
They are unable to increase the degree of voids between the cement grains.
The graphite has a plate-like shape (Fig. 2,a) In [14] it was theoretically established and experimentally confirmed that in order to obtain a fine-dispersed structure in the casting, it is necessary to have a certain number of crystallization centers in the melt.
The required number of crystallization centers can be obtained with modifiers based on the ultrafine particles.
The structure of cast iron with: a – lamellar graphite, FS75 modifier; b – vermicular graphite, chamber product-based modifier With an increase in the melting rate of the electrode due to an increase in the welding current, the heat input into the welded joint increases, which can overheat the metal [17, 18] and increase the austenite grain and brittleness of the welded joint.

The investigation of the difference in grain size is found to have a significantly effect on the surface roughness and the grinding force when grinding [4].
The statistically designed model of the ground surface roughness is proposed by considering of five parameters, which are the grain size, the table speed, the number of sparkout passes, the number of dressing passes and the dressing cross feed rate [7].
Seker: An Investigation into the Influences of Grain Size and Grinding Parameters on Surface Roughness and Grinding Forces when Grinding, Journal of Mechanical Engineering, Vol. 56 (2010), p. 447-454 [5] H.

Based on the number of plasticity, the rock belongs to sandy loam, and the mass content of the pelitic rock fraction is 24%.
In the microstructure, the CSH-2 modifier is used to diagnose individual coarse-grained prismatic crystal intergrowths with perfect cleavage (refer with: Fig. 2, b) characteristic of C2SH (A), which are located among the CSH (I) thin crystalline fibers.
The microstructure of the obtained modifier in the system CaO-SiO2-H2O by C:S=1:1 (a) and C:S=1:1 (b) Based on the analysis of the x-ray of the CSH-1 modifier after TBO (refer with: Fig. 3, a) there is an increase in the number of low-basic calcium hydro silicates (d = 3.08, 2.83 Å), as well as reducing the amount of free SiO2 (d = 4.25, 2.45, 2.29 Å) and Ca(OH)2 (d = 4.928, 1.791 Å).
The influence of quartz grain size within the system CaO–SiO2–D2O, Progress in Crystal Growth and Characterization of Materials. 58 (2-3) (2012) 84-91
Cherenkova, Effect of microfillers based on natural wollastonite on the properties of fine-grained concrete, Construction Materials and Products. 2 (6) (2019) 20 – 28

These precipitation phases in the grain matrix are the main age hardening mechanism.
This concept restricts the number of metal alloys that can be studied, such as iron, copper, aluminum, magnesium, tin or titanium.
In addition, the precipitation of AlNi phase in the matrix dendrites became larger and globular shape inside the grain matrix.
However, since the morphology do not show the Cr5Fe6Mn8 phase (σ-phase), the compound is finer grain.
These precipitation phases in the grain matrix are the main age hardening mechanism.

A comparison of a number of growth variables for EFG to some of these methods is given in Table 2.
Grain dimensions are typically greater than a few mm, and may be as large as a few cm.
There are few grain boundaries.
Controversy still exists as to whether dislocations and grain boundaries participate in enhancing hydrogen diffusion.
High angle grain boundaries are generally not passivated Fig. 5.

Building the system of particle model In order to make simulation more accurate,five real typical stone shapes from stone grain heap were found to build the particle model as a reference in EDEM.
(a) Spherical stone (b) Cubic stone (c) Triangle stone (d) Cone stone (e) Long stone Fig.1 Five real typical stone shapes (a)spherical particle (b)Cubic particle (c)Triangle particle (d)Cone particle (e)long particle Fig.2 Five simulation particles The number of particle size distribution was normal distribution, each particle size included five simulation particles.5050 particles were generated by particle factory in EDEM.
Table.1 The number of particle size distribution Particle size (mm) Totle Sphere Long Cube Cone Triangle 15 300 300 No No No No 20 400 80 80 80 80 80 25 500 100 100 100 100 100 30 600 120 120 120 120 120 35 700 140 140 140 140 140 40 800 160 160 160 160 160 45 700 140 140 140 140 140 55 450 90 90 90 90 90 60 250 50 50 50 50 50 70 150 30 30 30 30 30 80 100 20 20 20 20 20 90 50 50 No No No No 100 50 50 No No No No DEM simulation 20 groups test data shown in Table 2 were used to simulate screening processes in EDEM.
Screening processes were shown in Fig.3.Vibrating direction angles were random number between 5°and 70°, leaning angles of screen were random number between 3°and 20°, vibration frequencies were random number between 5Hz and 35Hz, amplitudes were random number between 3mm and 12mm.

Solar power research primarily focuses on studying fine-grained materials with a perfect spherical shape but natural and manufactured granular materials are typically irregular in shape.
Coordination number and RDF analyses.
Their minimum coordination number is around 3, while spherical particles can have a minimum of 2.
In contrast, spherical particles' curve is left-skewed, peaking at a coordination number of 6.
(a) Distribution of coordination number and (b) RDF for all samples.

Set up nodal value of the chain table (-1,-16,-2 ) to show the initial front table; ③Number of balls: n=0; (2) Generate balls at each time step ① Randomly generate the radius of the ball; ② If the node is added in the first layer; If n=0, then: <1> set the value of b as the value of head pointer of the front chain table; <2> calculate the coordinate position of generated balls on the basis of b and left boundary according to the requirement of ball contact; <3> Insert n element after the node numbered as -1; Otherwise: <1> set the value of b as the value of the node whose number is the next one after the present number of balls in the front chain table; <2> calculate the coordinate position of generated balls on the basis of b and the present ball; <3> if there is no out of boundary after adding this ball, then: insert element n after the node of the present number of balls (no need to examine whether it overlaps with the prior ball) ; Otherwise: get the position
of the ball on the basis of right boundary and the present ball, insert the node, delete the node of lower boundary, the number of nodes =-1; ③ If this is not the first layer addition; Find the node and calculate the position of the ball; Judge whether it overlaps with the prior ball.
Discrete element simulation of an assembly of irregularly shaped grains: quantitative comparison with experiments[C].

A new algorithm called parallel multi-objective genetic algorithm(PMGA) is developed using the coarse-grained parallel programming model with the support of MPI.
The number of the cascade channel mesh is 11264.
The optimized nerve cell number of the inter-layer is 31,and the optimum structure of the ANN is 8-16-15-3.
Fig.3 Geometry of the optimized and initial cascade airfoil The Mach number distributions are obtained and shown in Fig.4 and Fig.5.
So the Mach number of the flow in front of the normal shock descends and the total pressure recovery coefficient increases.

The algorithm can decrease the synchronization hop count by constructing a spanning tree, and uses two-way SRS in inter-cluster and one-way ROS in intra-cluster to reduce the number of messages required for the network synchronization.
Figure 2 reflects changing trend of the algorithms‘ mean synchronization error as the increasing of the nodes number.
Fig.2 WSN Error’s changing trend Conclusion For the problem that classical time synchronization algorithms existing in large-scale WSN, this paper have proposed a time synchronization algorithm based on cluster-tree that constructs a spanning tree to effectively reduce synchronization hop count, and uses two-way SRS in inter-cluster and one-way ROS in intra-cluster to reduce the number of messages required for the network synchronization.
Fine-grained network time synchronization using reference broadcasts [J].