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Analysis of Fig. 1 and the data summarized in Table 1 shows that the most coarse-grained structure was obtained for the unmodified alloy, cast to ATD probe (sample 1),in which the average area of the silicon surface reach the value of 4317 μm2, the number of silicon precipitates per one mm2 was 9, and the shape factor amounted only 0.39.
For samples 1-4, in which the solidification has occurred in the standard ATD probe (with use of different variants of cooling), the obtained results of average area, the number of precipitates and the shape factor of silicon crystals, does not show a significant difference.
The use of graphite as the mold material (sample 5) for the unmodified alloy, caused (compared to the standard ATD cup) reduction of silicon crystal dimensions of about 400 μm2 and increase the number of them per 1 mm2.
Evaluation of selected stereological parameters of hypereutectic silicon crystals Sample Average area [µm2] Number of silicon precipitates [1/mm2] Aspect ratio F 1 4317 9 0.39 2 2453 28 0.58 3 2243 33 0.61 4 2333 37 0.62 5 3932 21 0.42 6 540 69 0.68 7 435 82 0.66 8 193 167 0.70 Summary This paper presents the methodology allowing to assess the impact of a number of parameters such as: modification process, the choice of material for the mold and the use of additional active cooling to the form.
The performed research, includes an analysis of the structure of obtained ingots (made from silumin AlSi17), led to the following conclusions: · The alloy modification , in each case leads to a reduction of average area of the hypereutectic silicon precipitates, increasing the number of them from 9 to 28 per mm2 (for the sampler ATD) and 21 to 69 per mm2 (for a graphite mold)

Introduction Sweet broad pea (Pisum sativum L.) which is an annual herb legume peas are climbing plants, grain can be eaten.
The adventitious buds of internodes inoculated into the medium for rooting, and observed the effect of NAA on adventitious buds rooting, counted root number and the root rates.
Table1 Effects of different hormone combinations on callus induction hormone leaves Internodes Cotyledons Stems BA NAA 2，4-D Number Induction rate Number Induction rate Number Induction rate Number Induction rate 0.0 0.0 0.5 30 83.3 30 100.0 30 10.0 30 93.3 0.5 0.5 0.0 30 23.3 30 46.7 30 0.0 30 43.3 1.0 1.0 0.0 30 90.0 30 100.0 30 13.3 30 96.7 Effect of 6-BA concentration on explants differentiation bud.
Table2 Effects of 6-BA on the differentiation and Germination of different explants Explants 6-BA(mg/L) numbers differentiated explants Differentiation rate/% Cotyledons 0.5 1.0 2.0 4.0 30 30 30 30 1 0 2 0 3.3 0.0 6.7 0.0 leaves 0.5 1.0 2.0 4.0 30 30 30 30 0 0 0 0 0.0 0.0 0.0 0.0 Internodes 0.5 1.0 2.0 4.0 30 30 30 30 11 19 26 5 36.7 63.3 86.7 3.3 Stems 0.5 1.0 2.0 4.0 30 30 30 30 0 0 0 0 0.0 0.0 0.0 0.0 Adventitious root induction.

Concrete durability, and water and other harmful liquids, gases, the number of its internal flow, scope, and therefore high impermeability of concrete, the durability is like.
At present, concrete waterproofing agent to improve the main principle of impermeability of concrete by increasing the density of concrete, reduce the number of unwanted holes, shrinkage compensation mechanism such as waterproof.
Therefore, by comparison research in rational use of concrete superplasticizer, while adding Mixed materials can greatly increase the impermeability of concrete, while improving the performance of concrete. 2.1 Mechanism Analysis of fly ash Fly ash contains more than 70% of glass beads, full grain shape, smooth, dense texture.
Because of its chemical composition contains a large number of active SiO2 and Al2O3, in a wet environment with Ca (OH) 2 and other alkaline substances in a chemical reaction to produce calcium silicate hydrate, hydrated calcium aluminate and other cementitious substances, powder ash products and enhance the role and can play a concrete block of concrete in the capillary tissue, improve corrosion resistance of concrete.
Reduce the number of the big holes, increasing the number of holes, the average pore size decreased, the distribution more reasonable.

The diameter of latex grain is an important index of good or bad performance of the emulsion[1-3].
Emulsifier concentration [s] and the number of micelles [Nm] has the following relationship: [ Nm ] ∝ [ s ]0.6 To obtain more latex number, small particles diameter, the amount of emulsifier is the more the better.
Both of them would cause the number of latex particles increased, the diameter decreased.
The initiator concentration was too low, resulting in too small number of free radicals and latex particle increasing.
This is because when other conditions were certain, the number of the latex particles was certain.

A fabric made of jute, a natural occurring fiber, was used as reinforcement in a fine grained cementitious matrix with a low content of calcium hydroxide.
As can be observed in Fig. 4, with the increased number of layers, there is an increase of cracks.
The composite reinforced with 3 layers presented six cracks and the composite with 5 layers eleven cracks. 3 layers 5 layers Matrix (a) (b) Figure 4 – Influence of the number of layers on the tensile behavior of textile cementitious composites reinforced with jute fabric: (a) tensile stress and crack spacing vs. strain (b) photos of composites reinforced with 3 and 5 layers of fabric without treatment.
The composite with 5 layers with fabric impregnated by 50 min had the greatest number of cracks and smaller spacing. 5 layers treated by 10 min 5 layers without treatment Matrix 5 layers treated by 50 min (b) (a) Figure 5 - Influence of the treatment with polymer on the tensile of textile cementitious composites reinforced with jute fabric: (a) tensile stress and crack spacing vs. strain (b) photos of composites reinforced with 5 layers of fabric with treatment.
The composite with 5 layers with fabric impregnated by 50 min presented the greatest number of cracks with lower spacing.

As for Reynolds number, a more accurate explicit equation proposed by Zigrang and Sylvester has been used here.
The same terminal velocity equation has been used in Das’s model to track the movement of particles, but there are some differences in the determination of Reynolds number.
A correlation is used by Das for the determination of the Reynolds number as a function of Archimedes number
(3) Where The latter is the dimension-less Archimedes number.
Free settling tests of 25 samples, which is narrow density and narrow size level average grains, were undertaken.

Abstract: Study on the effect of liquefaction mechanism on the performance of ECC, adding rubber powder mesh size effect on the performance of ECC, respectively, to 40 mesh, 60 mesh, 80 mesh and 100 orders at the same content of rubber powder and 40 mesh in different dosage on ECC compressive strength, flexural toughness was analyzed, results show that: the use of the mechanism of liquefaction of mixing rubber powder in cement based materials, with the increase of ECC number increased ductility, at the same time reduce the compressive strength is larger, rubber powder content in 12%, the comprehensive effect is ideal.
Sand: the sand grain size is 0.22~0.37mm.
a) b) Figure 2.a) Compressive strength of G1~G4 b) Compressive strength of G1‘~G4‘ Conclusion 1) the liquefaction mechanism to adjust the ECC ratio, thus liquidity or cement matrix and reducing segregation, achieve high ductility cementitious matrix and multiple cracks and thus more easily. 2) rubber powder mixed with larger mesh size, compared to the number of small can more easily achieve ECC high ductility, but the maximum carrying capacity is greatly reduced, the compressive strength has greatly decreased; with the increase of rubber powder mesh, ECC corresponding improved ductility.

In the annealed specimen, relatively large particles of Fe16N2 were formed with low number density, while in the deformed specimens, dislocation substructures due to cold rolling were disappeared by ion-implantation and fine particles were densely formed.
Number density of the �" particles in (b), cold rolled with 90 %, is obviously higher than that in (a), annealed specimen.
On the other hand, in the annealed specimen, interstitial iron atoms firstly diffuse to sinks, such as surface and grain boundaries, remaining vacancies and nitrogen atoms.

The critical need for use of a scientific approach to optimize plunge depth for a given tool material and test machine in fewer number of steps is emphasized.
The weld nugget (WN) is essentially a recrystallized central portion of the TMAZ and has substantially smaller equiaxed grains than the base metal.
Grains are elongated in the direction of rolling with the size varying from 300 μm to 500μm.
Invention of the FSW process made a number of aluminium alloys, especially the copper containing 2000-series and 7000-series, receptive to welding, which were previously considered to be unweldable primarily because of their sensitivity to cracking due essentially to a wide freezing range during solidification coupled with the formation of partially melted zones in the heat-affected zone near the fusion line.
Further, a higher heat input favours: (i) coarsening of the grains, (ii) an elimination of hardening to a wide range of work hardened materials, and (iii) over-aging in precipitation hardenable aluminium alloys in the HAZ.

Algeria is today faced with an ever increasing problem of providing adequate yet affordable housing in sufficient numbers.
Grain size distribution.
Figure 10 shows the percentage of weight loss with the number of wetting-drying cycles for static and dynamic compaction.
This figure indicates that the weight loss increases with the number of cycles.
Even for dynamic compaction, with an incorporation of 5% cement content, the weight loss evolves according to the number of cycles of wetting-drying.