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Straw as a raw material is an affordable and economically profitable material, besides being after harvesting grain crops, most of the straw is burned on purpose.
The straw building elements production development relevance by the need to solve a number of social and economic problems, such as reducing the construction materials cost, increase the economic efficiency of construction production based on the integrated straw raw materials use.

Fineness (grain size) of additives is the most limiting factor on current level of concrete technology.
It is important to note that while the physical effect on the hydration kinetics (increasing the number of nucleation sites) is similar with both used nanoparticles, calcium carbonate alone is not a pozzolan and not participate in the reaction with the portlandite.

Mix-design SR16 where Portland cement (with fast development of strengths) was replaced by 15% with finely grained blast furnace slag reached lower values than reference concrete and mix-design R22.
Acknowledgements This work was financially supported by “Central European cooperation for industry” by project “Centrum pro efektivní a udržitelnou dopravní infrastrukturu (CESTI), number TE01020168 and FAST-S-17-4737 “Vliv technologií povrchových úprav na trvanlivost betonových dlažeb” References [1] SVOBODA, Luboš, Zdenka BAŽANTOVÁ, Milan MYŠKA and Jaroslav NOVÁK.

The wear resistance of such created structures is limited to the intrinsic capability of the steel to improve its strength, e.g. by strain hardening or grain refinement, and does often not reach the required level.
Fig. 6: Initial roll topology and after different cycle numbers The high wear resistance of the laser implanted spots is directly related to the high hardness of the structures (1500 HV1 in this case).

It can be observed that a number of coarse second phase particles distribute along the extruding direction.
There are no small particles precipitate observed inside the grains, it might be attributed to the samples were quenched into the water quickly after solution treatments.

As power output of single cell is limited, it is necessary to assemble a number of cells to form a “stack”.
As reported in the literature [17], grain boundaries are helpful to improve the conductivity of ceramic layer by providing more transport path for electrons.

In contrast, the blended cement with limestone showed the lowest value of specific surface area due to the admixture, whose medium grain is specified in value of 40 µm, but nevertheless does not reach fineness of deagglomerated clinker to a specific surface of approx. 500 m2.kg-1.
Acknowledgements This work was financially supported by project number: GA14-32942S “Effect of fluidized bed ash on the thermodynamic stability of hydraulic binders” and project No.

Introduction Investigation of rare earth (RE) doped up-conversion (UC) materials has been attractive still due to a large number of potential applications such as detectors for infrared radiation, fluorescent labels for sensitive detection of biomolecules, and UC lasing [1-4].
Typical microstructure for Er3+-doped CaTiO3 particles are shown in Fig. 2(b) The grain size of the phosphor particles was about 150 ~ 200 nm in the observed area.

The basic material properties of the tested graphite are as follows: the mean grain size is of 300 mm, the porosity of 15%, the bulk density of 1830 kg/m3, the mean tensile strength of 30 MPa, the Young’s modulus of 8.00 GPa and the shear modulus of 3.30 GPa.
At least three samples were prepared for each of the 15 specimen geometries described above, with a total number of 45 specimens.

Thermal stresses have been identified to be responsible for crystal defects, and therefore there have been a number of reports on stress distributions in SiC crystals.
In general, SiC crystals are grown in a strong lateral thermal distribution environment from the crystal peripheral toward center, and the thermal distributions are crucial in order to maintain monopolytype growth as well as to suppress disturbance of the single crystal growth, i.e. polycrystalline grain formations [5, 6].