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For this reason, fluidised bed fly ash grains are characterised by an increased content of reactive free CaO and sulphates, which is the reason why the use of fluidised bed fly ash as an active admixture in concrete mixtures is not permitted for the time being.
Basic physical parameters of input raw materials Raw material Specific weight [g/cm3] Specific surface [cm2/g] CEM II/A-S 42.5 R, Mokrá 3.11 4010 High temperature fly ash Mělník (MEL) 2.21 3280 Fluid fly ash Zlin (ZL) 2.82 9930 The morphology of high temperature fly ash and fluidised fly ash grains was investigated using scanning electron microscopy (SEM) and is shown in Fig. 1.
From the images, it can be seen that the grains of high temperature fly ash have an almost regular spherical shape, whereas the grains of fluidised fly ash are highly irregular and porous, which is closely related to their water content.
However, in order to start using fly ash safely in concrete, a large number of further experiments are required to map the exact effects of using fly ash on the cement composite, especially over the long term and when the composite is exposed to different types of aggressive environments.

These methods have the advantages like well-proportioned grains, high purity, and low thermal treating temperature.
Wave number 1091.2, 1181.2, 1107.4 and 1066.6 cm-1 corresponds to bending vibration of bond C-O.
Wave number above 900 cm-1 is the characteristic area.
Wave number in 804.9 and 817.3 cm-1 is the stretching and bending vibrates of La-O bond, wave number in 597.3, 576.8 and 598.3 cm-1 are the stretching and bending vibrates of Co-O bond, which is accordant with XRD analysis.
Most of the grain boundaries are clear, also mixed with a small amount of flocculation which the boundaries are blurred.

This technique reduces drastically the number of experiments that are required to model and optimize the responses.
The two points are considered before selection a particular orthogonal array for conducting experiments; i.e. the number of parameters and interactions of interest and the number of levels for the parameters of interest.
Each of three level parameters has two degrees of freedom (DF) [DF equals to the number of levels minus one].
Significant grain refinement can be noticed in the alloy on FSW in the second joint.
Density of precipitates has decreased as a result of coarsening; Grain boundary precipitates have also coarsened.

The quality of the best solutions increases systematically with the number of iterations (populations).
There exist a number of methods for this calculation (see e.g., 6-12).
The standard functions are normalized (Eq.2), hence the weight coefficients give also the volume fractions of grains whose orientations are covered by a given standard function.
Moreover, this difference grows rapidly (in favor of GAM) with increasing number of Gauss standard functions.
Accommodation factor vs. number of generations 4.

Ionic transport number was evaluated using DC polarization technique and it reveals the conducting species are predominantly ions.
Transport number was measured using DC polarization method.
Transport Number Studies The ionic transport number (tion) has been evaluated using the DC polarization method.
On addition of 20wt.% of Mg(CF3SO3)2 salt, the well distributed spherical and elongated grain structures in the film is observed as shown in Fig. 5(c).
The ionic transport number estimated by the DC polarization method revealed that the ionic transport in the GPE films is due to Mg2+ ions.

Certain microstructure features are quite amenable to high resolution characterization over substantial fields of view, such as grain size and orientation information.
(cf. [6]), and a number of other emerging multiscale homogenization approaches.
Given n, number of decision variables p, number of equality constraints q, number of inequality constraints m, number of system goals gi(x), constraint functions Find x (system variables) di- ,di+ (deviation variables) Satisfy System constraints: g(x)=0 i=1,...
For given Al and Fe2O3 particle size distributions, for example, Fig. 10 shows the number density of reaction initiation sites as a function of mean void size and volume fraction.
Paper Number: ASME DETC2000/DTM-14579 (2000). 5.

Organo-Mineral Additive Based on Mixed Clays Valentina Loganina1, a*, Jury Skachkov1, b ,Valentina Demyanova1, c, Tatyana Uchaeva1, d 1Penza State University of Architecture and Construction, Street Titov, 28, 440028 Penza, Russia aloganin@mail.ru, boffise@pguas.ru, cie@pguas.ru,d uchaevatv@mail.ru Keywords: Organo-mineral additive, Adsorption, Grain size composition, Dry buildingmortars Abstract.
It was found that the modified clay (organoclay) is well dispersed in water: the number of fine fractions increases.
When applying Kameshkirskiy clay the number of particle of size less than 0.001 mm in the organoclay is 45.88%, the number of fractions 0.01-0.005 mm is 16.18% and in the test sample is respectively 36.14%, and 27.38%.
When applying Vorobyevskiy clay the number of particles smaller than 0.001-0.005 mm in the organoclay is 23.54%, the number of fractions 0,01-0,063 mm - 31.64%, while in the test sample is respectively 2.59% and 43.44% .

Pit related horizontal grain degradation within the austenitic phase is associated with the lower corrosion resistance of the γ-phase according to PREN [19].
Cathodic protection that is the application of a negative potential increases the number of cycles to failure (figure 2).
Pre-charging specimen with hydrogen clearly decreases the endurance limit by 80% of number of cycles to failure (figure 2).
Pre-charging specimen with hydrogen clearly decreases the endurance limit by 80% of number of cycles to failure.
At the applied cathodic potential USHE = 36 mV the number of cycles to failure are significantly lower.

Schwedt 4,e 1 Cairo University – Faculty of engineering – Cairo- Egypt, British University in Egypt at the time of doing this work 2 Helwan University – Faculty of engineering – Cairo- Egypt, 3 Scientific & Technology Centre of Excellence Salam City – Cairo- Egypt, 4 Gemeinshaftslabour – Aachen University Germany asaiman @eng.cu.edu.eg, ielmahallawi@bue.edu.eg, bhoda1947@yahoo.com, clailashehata@yahoo.com, dasmaaamer@yahoo.com, dmayer@gfe-rwth.aachen.de, eschwedt@gfe-rwth.aachen.de Keywords: Aluminium silicon hypoeutectic alloys, strength, T6, grain refinement, SEM micro-analysis.
In this work a number of cast samples of A356 were prepared by rheo-casting in a specially designed and built furnace unit allowing for the addition of the nano-particles into the molten Al-Si alloy in the semi-solid state with mechanical stirring.
Similar behavior has been reported, though the alloys were manufactured in a different manner, supporting the hypothesis that the addition of Al2O3 nano-particles to the A356 alloy has reduced the grain size of the aluminium matrix [3].

The grain size of the weld region also plays a major role in deciding the joint properties.
The grain size of the weld region is influenced by the heat of the welding process.
With constant Vee preparation angle, in specimens welded with larger current, volume of count number and duration time of signals are higher than the other, but energy of signals are lower than the other which it can be due to higher residual stress. 3.
With constant welding current, in specimens welded with larger Vee preparation angle, volume of count number and duration time of signals are higher than the other, but energy of signals are less than the other which it can be due to higher residual stress.