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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.

It is known that when mechanical strain exceeds the irreversible strain, cracks will form at high-angle grain boundaries and cause the degradation of critical current [12].
The samples were numbered 1#, 2#, and 3# respectively.
Parameters of the samples used in monotonic tensile experiment Sample number 1# 2# 3# Critical current Ic0 (A) 158.96 156.43 152.34 Strain 0.485% 0.458% 0.439% Normalized critical current 96% 96% 93% Fig. 2 Normalized critical currents and stress versus strain relation in copper reinforced Bi-2223/Ag (77K, self-field) Fig. 3 Stress-strain curve in copper at room temperature Critical currents versus repetitive tensile stress relation.
The samples were numbered F1, F2, F3, and F4 respectively.
Effect of tensile strain on grain connectivity and flux pinning in Bi2Sr2Ca2Cu3Ox tapes.

Among the advantages of this technique as compared to other tools such as transmission electron microscopy, is the fact that accurate, quantitative numbers can be provided for the characteristics of the precipitate size distributions, measured on a very large number of particles.
Al3Zr precipitates are used as anti-recrystallisation agents due to their ability to pin grain and subgrain boundaries.
Since Zr and Sc atoms have very different atomic numbers, it can be expected that the chemical inhomogeneity inside the precipitates results in a specific small-angle X-ray scattering signal.
Once these parameters are known for a given metallurgical state, the average precipitate composition is known and the precipitate volume fraction fv can be calculated from the integrated intensity Qo : ()2mp 2 o v 2 Q f ρ−ρπ ≅ , where ρp and ρm are the electron densities of the precipitate and matrix and ()∫ ∞ = 0 2 o dqqqIQ is calculated from the experimental data. 0 50 100 150 200012345678 5°C/min 10°C/min 430°C/min Time (h) Precipitate radius (Å) 0 100 1 10 -3 2 10 -3 012345678 5°C/min 10°C/min 430°C/min Time (h) Precipitate volume fraction 0 20 40 60 80 100 012345678 Time (h) Zr/(Zr+Sc) in the shell (%) 5°C/min 10°C/min 430°C/min 10 100 1000 10000012345678 5°C/min 10°C/min 430°C/min Time (h) Precipitate number density (µm-3 ) Figure 5: Precipitation kinetics at 450°C of the AlZrSc alloy, as a function of the heating rate: (a) precipitate size, (b) precipitate volume fraction, (c) composition of the
These features of fast nucleation and slow growth and coarsening enable to obtain a remarkably stable microstructure of fine Al3(Zr,Sc) dispersoids, which have proven to be very effective in controlling the grain size of many Aluminium alloys.

In terms of nucleation and growth, when a layer is cooled to 700°C, a large number of fine β-particles nucleate.
This results in a smaller amount of growth of the columnar structure, that results in smaller columnar grains at the top layer.
The martensitic decomposition is a classic “nucleation and growth” process, and when a layer is cooled to 700°C, a large number of very fine β-particles nucleate.
The regions close to the upper edge are the last to be printed and hence are subjected to a lower number of reheating/cooling cycles.
The less repeated heating results in a lower amount of growth of the columnar structure, and subsequently smaller columnar grains on the top layers are obtained.

The addition of TiC significantly improved the grain size and enhanced the strength of the composites.
The composite samples treated for 1 hour followed by aging for 2 hours also have a higher number of precipitates than the samples aged for 1 hour only [17].
Hybrid matrix composite compositions utilized in this investigation Composite Number AA6061 wt% TiC wt% Mos2 wt% 1 100 0 0 2 89 8 3 3 88 10 2 Fig 1.
This is due to the formation of fine grains of aluminum and magnesium precipitates in the composite, which allows to resist plastic deformation under different loads and sliding distances better.
Rockwell Hardness number for various composition Composite specimen As Cast Age hardening AA6061 44.3 56.4 AA6061+8%Tic+3% Mos2 59.02 91 AA6061+10%Tic+2%Mos2 63.1 99.3 Fig 6.

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.

Introduction In the effective short fatigue crack (ESFC) criterion proposed by Zhao et al. [1], the definition of ESFCs density is the average number of micro-cracks per unit area in the initial zone of dominant ESFC (DESFC) in MSC stage.
Compressive residual stress and heavy plastic deformation imposed on the surface grains due to cold work make it difficult for the cracks to nucleate and propagate at the rolled surface [7, 8].
C1 and C2 in Fig. 3b coalesce with each other and become a new crack C1 in Fig. 3c, the total number of micro-cracks increases stably.
Crack numbers of Fig. 3d-e are 9 and 11, respectively.
Compressive residual stress and plastic deformation are imposed on the surface grains and make it difficult for the cracks to nucleate and propagate at the rolled surface.

It requires the investigator to live together with the investigated objects for some time, and to observe, to understand and to be awareness of their social as well as cultural from it. 1.2 Research object On March 23, 2011, we chose Huofeng village of Quejia town as our research object, and selected a number of local residents to face-to-face interview while we observed.
Obviously, the interests of farmers of relatively weak competitiveness are severely squeezed. 2.2 Existing problems First, returning farmland to forest makes the local ecological environment greatly improved, the forest coverage rate significantly increased and wildlife species and amount apparently increased, but also leads to a surge in the number of grain-eating birds, which causes the prominent phenomenon that “human fighting birds over food”.
The nation pays attention to agriculture, rural areas and farmers, and gives out a certain amount of agricultural subsidies, but “agricultural subsidies” is a complement to the plot of farmlands, and there is no subdivision of whether to grow grain, so some farmers live the farmlands fallow to work outside the home on the one hand, and on the other hand still get the agricultural subsidies.
After a number of years, they will go back home use the accumulation to rebuild their houses.
A large number of young labor outflow causes seriously lacking of young adults, and the average age of the village leadership is about 60-year-old.

Such equipment makes it possible to perform large numbers of cutting operations (e.g., milling, grinding, sawing, polishing) by means of diamond impregnated tools.
According to our methodology, the testing procedure establishes a certain number of cutting slots or runs.
The total number of runs depends on the characteristics of the workpiece material and type of tool.
Pink Porriño South African Black Biotitic Granite, with large grains and with some irregular fractured megacrystals of dark rose K- feldspar Gabbro, with an homogeneous distribution of very dark pyroxene and grey feldspar grains (in the boundary of the former) Quartz (35%) K-feldspar (40%) Plagioclase (13%) Biotite (11%) Other (1%) Plagioclase (55%) Pyroxene (45%) Fig.2.
(a) (b) The tool weight loss values were measured after a performing a constant number of runs (150) at a constant force against each type of rock.

However, compared with experimentally measured temperatures and nodule size distributions it has been shown that such a solidification model underestimates the nodule number density after solidification is complete.
The number of new nodules as a function of time and temperature is given by the open circles in Fig. 2a.
Instead multiple nodules can be embedded in the same austenite grain.
Numbers refer to the particles described in Fig. 6.
Atwood, Transgranular liquation cracking of grains in the semi-solid state., Nat.