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Great emphasis is placed on the study of protection against sulphate corrosion and there are a big number of studies focused on predicting its course [7], [8], [9], [10].
At the same time, a number of studies are focused on slowing down degradation by partial substitution of suitable additives and secondary raw materials for Portland cement [12], [13].
As for FBC fly ash, fly ash particles do not melt, grains remain porous, their structure is layered and they have a large specific surface area.
Waste foundry sand contains grains of fraction which are smaller than 4 μm and they are used as microfiller.
Recommended replacement rate for fine grain fractions is in the range of 20–30% [25].

Up to now, a number of high damping alloys such as Mn-Cu and Fe-Cr have been developed and successfully applied in ship and railroad industries [3, 4].
Further increasing Nb content to more than 1%, large amounts of white particles with irregular morphology present and most of them are distributed along the grain boundaries.
(ii) A number of particles with various sizes are randomly distributed inside the ε martensite, at the ε martensitic variants boundaries and γ/ε interfaces.
Shin et al. [30] found that, in Fe-17Mn, the ultra-fine grained sample containing a low volume fraction of ε martensite possesses a damping capacity comparable to that of the coarse-grained sample with a high ε martensite fraction.
De Cooman, The effect of grain size on the damping capacity of Fe-17 wt%Mn, Mater.

After further aging at 300oC for 3h, a great number of fine ScAl3 particles are precipitated in the Al matrix, which leads to a considerable precipitation hardening effect, thus the strength and hardness are increased obviously.
It is known that ScAl3 particles formed during solidification can result in an outstanding grain refinement [1,5] and the ones formed in the course of heat treatment can lead to considerable strengthening effect [6,7] in Al-alloy systems.
A formula to describe the equilibrium concentration of vacancy in lattice is as following[12]: NV/N=exp (-QV/kT) (1) where NV stands for the equilibrium number of vacancies, N the total number of atomic sites, QV the energy required for the formation of a vacancy, T the absolute temperature in Kelvins, and k Boltzmann’s constant of 1.38×10-23J/atom-K.
After further aging at 300oC for 3h, a great number of fine ScAl3 particles are precipitated in the Al matrix, which leads to a considerable precipitation hardening effect, thus the strength and hardness are increased obviously.
(3) After further aging at 300oC for 3h, a great number of fine ScAl3 particles are precipitated in the Al matrix, which leads to a considerable precipitation hardening effect, thus the strength and hardness are increased obviously

Introduction Severe plastic deformation (SPD) for metallic materials produces ultra fine grains (UFG) [1-3].
Figure 5 shows variation of fp as a function of the number of ECAP passes.
With increasing the number of ECAP passes, fp in route A is strongly increased.
Fig. 6 Mean size of Al3Ti particles as a function of the number of ECAP passes.
Fig. 6 shows mean size of Al3Ti particles as a function of the number of ECAP passes.

Results and Discussion SEM image of the ceramic surface is shown in Fig.1, show- ing a typical microstructure of electronic ceramics with homogeneously distributing grains in diameter of about 8 um.
Fig. 5 Bad percentage (left) and voltage distribution (right) of capacitors after the thermal shock Table 1 Insulation resistance and bad rate of voltage withstanding after damp heat Insulated resistance after damp heat Serial number Epoxy resin (g) / curing agent (g) Curing temperature / time R (average) > 10GΩ Bad rate of voltage resistance A 100 / 27 365 GΩ OK 0 % B 100 / 29 195 GΩ OK 0 % C 100 / 31 91 GΩ OK 0 % D 100 / 37 120 ºC / 1 h +130 ºC / 1 h. 50 GΩ OK 0 % Table 2 Bad rate of voltage withstanding of endurance with DC 10 kV at 100ºC for 500 h Serial number Epoxy resin (g) / curing agent (g) Curing temperature and time Bad rate of voltage withstanding A 100 / 26.8 0% B 100 / 29.4 0% C 100 / 31 0% D 100 / 37 120 ºC /1 h+130 ºC /3 h. 0%

But Ag prepared by solvated metal atom impregnation and functional ion pre-adsorption method can avoid some process such as drying, calcinations and high temperature reduction and so on Consequently, Ag has the properties of smaller average grain diameter, larger specific surface area and higher electrocatalytic activity in Ag/C catalysts prepared by solvated metal atom impregnation and functional ion pre-adsorption method [5, 6].
Table 1 The fabrication of Ag/C catalysts Number Mass ratio （PVP/ AgNO3） Concentration of AgNO3（mol/L） Concentration of NaBH4（mol/L） Ag/C catalysts（Ag%） 1 2︰1 0.01 0.01 20 2 2︰1 0.02 0.01 20 3 5︰1 0.01 0.01 20 4 10︰1 0.01 0.01 10 5 10︰1 0.02 0.01 20 3.2 SEM test Fig1-fig5 show the images of Ag/C catalysts obtained by XL30 ESEMFEG(SEM).
Table2 The results of XRD test of Ag/C catalysts Number Mass ratio （PVP/AgNO3） Concentration of AgNO3（mol/L） Concentration of NaBH4（mol/L） Ag/C catalysts(%) Particle size of Ag(nm) 1 2：1 0.01 0.01 20 38.2 2 2：1 0.02 0.01 20 76.6 3 5：1 0.01 0.01 20 33.4 4 10：1 0.01 0.01 10 23.6 5 10：1 0.01 0.01 20 25.1 3.4 polarizations curves Fig6 shows that the polorization curves of oxygen reduction on the electrode with Ag/C catalysts.As shown in Fig6, the electrocatalytic activity of Ag/C catalysts prepared by the polymeric complex protection for Ag(I) enhanced with increasing concentration of AgNO3, the electrocatalytic activity decreased with increasing concentration of AgNO3 at a certain mass ratio of PVP/AgNO3 and the electrocatalytic activity strengthened with increasing concentration of Ag at a certain mass ratio of PVP/AgNO3 and concentration of AgNO3.

During milling process, rice husk will separate from rice grain as a waste.
Rice husk with variety number of Malaysian Research (MR211) was obtained from Bernas Kuala Selangor while UF resin was supplied by Malayan Adhesive and Chemical Sdn Bhd at Shah Alam, Selangor.
The number of panels was 3 pieces per each trial.

Introduction Polycrystalline diamond compacts (for short PDC) are a kind of product composed of micron grain diamond and hard alloy object with the condition of high temperature and high pressure.
Table 1 PDC sample number Sample number Samper characteristic Remnant strsee ranking A Compound-anneal-abrasive process-anneal 3 B Compound-anneal-abrasive process 2 C Compound-abrasive process 1 (max) D Diamond micropowder 0 (min) (a) (b) Fig.2 XRD pattern of PDC Results and Discussion It is clear in the Fig.2 (a) and Fig.2 (b) that the back-bottom of spectral line increases when there is the residual stresses (σ) of PDC.

The head and central section of the molded parts is sand grain surface, and its surface roughness is Ra3.2um.
Conclusions We explore the processing technology of the cavity part and programming techniques on the basis for a number of analog processing after we reference peers processing experience and refer to a large number of related technical data.

BWS with coarse grain gritting and plastomeric covering substance was applied on the sealing layer.
Specimens identified with number 7 were reserves, the central part of the sample was left for further tests.
Registration number: CZ.1.07/2.3.00/20.0111, funded by European Social Funds, Operational program Education for Competitiveness and state budget of the Czech Republic and the research project TA CR No.