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Introduction From the demolition of old buildings, roads and various concrete structures there is always a lot of waste, that has not its own use, and it is stored in landfills, whose number is increasing.
The aim of the utilization of waste materials is the reducing number of landfills and saving the environment from carbon dioxide, which is produced for example in the production of cement.
Fine ground recycled concrete was used as filler with certain bonding properties of unhydrated cement grains in FGRC.
To obtain the best images from the microscope, the samples were gradually grinded and polished on apparatus Struers LabPol - by 5 sandpapers with fineness 300 grains/cm2, 500 grains/cm2, 1200 grains/cm2, 2400 grains/cm2 and 4000 grains/cm2.
On the images from the scanning electron microscope (Fig. 4 left column) the white areas represent the unhydrated grains of cement.

Metallographic observation of sintered material showed that microstructure contains small austenitic grains with size of 3-5 µm with fine carbides (1-2 µm) and carbonitrides distributed mostly on grain boundaries.
The analyzed area during XPS analysis was about 0.8 mm in diameter and thus a large number of particles (~1000 particles) was analyzed at the same time giving statistically reliable average result that represent the general powder surface composition.
Metallographic observation of sintered material showed that microstructure contain small austenitic grains with size of 3-5 µm with fine carbides (1-2 µm) and carbonitrides distributed mostly on grain boundaries.
Metallographic observation of sintered material showed that microstructure consists of austenite characterized by fine grains size of 3-5 µm with fine carbides (1-2 µm) and carbonitrides distributed mostly on grain boundaries, which confirmed theoretical predictions.

The mathematical model is as follows: The objective function is: The constraint is: Where, of which can be gray number.
(3) Total population constraint; the population borne by agricultural and urban land should not exceed the number of the predicted population in 2020.
(4) Social demand constraint From 1996 to 2005, the production of major agricultural products and grain has remained at a steady momentum, with an annual grain yield of 5487 kg/hm2.
Predicted by trend forecasting method, the city’s grain production will reach 6627 kg/hm2 in 2020; the model predicted value is 6979 kg/hm2, take 5487-5067.85 kg/hm2 for the gray interval, and the lower limit is the average annual grain yield from 1996 to 2005.
To meet the production and living needs of the people, estimated by the standard of well-off level, the required grain gray interval is 2.58108-3.24108 kg.

Silstones are the cemented clastic rocks with a grain size of from 0.05 to 0.005 mm, but as many authors emphasize, their lower boundary is quite conditional [10].
At the same time, the area of ​​contacts between particles progressively increases with a decrease in the grain size of the mass.
In Figure 4 micrographs of individual sieve residues grains, fired at temperatures of 900-1100 оС.
However, in the electron microscopic images, signs of baking are clearly visible - the formation of secondary pores, the melted form of the grains, etc.
There is a large number of closed pores with a size of 100 microns and less.

The heat affected zone can be divided into coarse grain zone and fine grain area due to the amount of heat and grain size.
The weld zone is composed of columnar crystals, and the grain size is larger than that of the base metal and the heat affected grains.
Figure5 (c), (d) is the heat affected zone, the heat affected zone from the weld to the parent material in turn for the coarse grain zone, fine grain area and semi fusion zone.
The coarse grain zone and fine grain zone organization is roughly the same as that by martensite, bainite, ferrite and austenite in martensite, but the coarse grain region of the ratio of the amount of the fine grain zone, and ferrite than the fine grain zone is less, so more coarse grain.
Acknowledge Project: 2016 Anhui university natural science key research project, project number: KJ2016A130 References [1] J.

Considering that the average flow is big in the dam site area, and it can take a certain range of leakage flow, in addition to the asymmetric geological lithology that the development texture fracture of fine grained granite on the left bank but the coarse grain granite on the right bank, an alternative project to reduce or cancel the grouting curtain of the riverbed coarse grained granite on the right bank is put forward.
While the seepage cut-off wall in the covering layer of riverbed should be deepen into weak weathered coarse grained granite layer.
While the seepage cut-off wall in the covering layer of riverbed should be deepen into weak weathered coarse grained granite layer.
As the grouting filling of fissures of coarse-grained granites on the right bank is more difficult than the fine-grained granite, scheme 3 is not economical from the point of the investment.
In the optimization design , the curtain grouting of dam riverbed bedrock's (beside dike part) coarse grained granite part canceled, the cut-off wall is adopted on the covering layer of riverbed and the right bank of dam, and deepen the cut-off wall to the weak weathered layer of coarse-grained granite on the right riverbed.

Internal factors are following: steel chemical composition, number and shape of non-metallic inclusions, microstructure of steel, strength properties [3, 4, 9-13].
Microstructure control is critically important for SSCC resistance, because crack propagation easily occurs along embrittled ferrite grain boundaries (Fig. 2).
Large deformations in the first stage of rolling were aimed at maximum austenite grain refinement by multiple recrystallizations.
Size of ferrite grains does not exceed 10 µm, size of bainitic regions – 50 µm, no banding.
Clean steel production and inclusion shape control minimized the number of crack initiation sites.

The structure of rods extruded according to variant I was composed of elongated grains and deformation bands (Fig. 1a), while the same rod subjected to an annealing process at 200°C, in addition to the elongated grains and deformation bands, also comprised a number of fine grains.
The longitudinal sections of rods showed the presence of elongated grains and/or deformation bands and bands composed of fine grains of similar colours.
Some grains had the boundaries of strongly arched shape.
From the grain size distribution it follows that there is little difference in grain size between the rods extruded according to variant I and variant II, while the smallest scatter in the grain size distribution was found in the rod extruded according to variant I.
In rods extruded according to variant I, the grains were elongated, while in rods extruded according to variant II, partly elongated grains were replaced by new equiaxed grains, thus proving the occurrence of the recrystallization process.

Single crystal deformation is governed by hardening laws for the critical resolved shear stress which account for the formation and dissolution of planar dislocation walls based on slip patterns (number and distribution of active slip) and changes in slip activity.
Each grain is modeled as an ellipsoid embedded in a homogeneous effective medium with average properties of all the grains.
Unlike the Taylor model, usually less than 5 active systems are activated inside each grain, and the strain is different from grain to grain.
The percentage of 'mixed' grains, operating both mechanisms simultaneously remained below 5%.
Tomé: Ultrafine Grained Materials IV.

The typical intergranular fracture characteristics of sugar candy morphology and a large number of second cracks along grain boundary have been found on the fracture surface in the alloy without pulse current.
While the number of the second cracks along grain boundary decreases and that of dimples increases in the alloy with the pulse current density of 1 kA/mm2.
When the current density increases to 3 kA/mm2, the size of dimples decreases and its number increases gradually.
And at the same time, there is an obvious decrease in the number of the cavities formed by breakage of the primary carbides.
The observation reveals that the appearance of the elongated grains is not obvious and the initial grain boundary is smoother when the deformation is 9%.