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There have been a number of developments encompassing different aspects of product development such as design, analysis and manufacture with reduction of product lead time as the main target.
When compared to the degassed samples from the green sand, all the Z-cast specimens showed much larger grain growth.
This means that traditional sand casting is able to achieve the higher strengths due to smaller grains, dictated by better heat transfer properties of the green sand mould material.
A coated mould however resulted in comparable grain size and consequent tensile strength for the specimens.
"Integration of CAD and rapid manufacturing for sand casting optimisation," Rapid Prototyping Journal, Volume 9, Number 5, pp 327-333

It can be noted from Fig. 1a that for the Al-30%Mg2Si alloy subjected to electromagnetic stirring and without adding phosphorus, the majority of primary Mg2Si phase has transformed from the fish-bone dendrite into the granular and rod-like, and the grains tend to become finer and have more round and regular shape.
When the adding amount of P is over 1.1%, the grains of primary phase exhibit a coarsening trend.
When the holding time is prolonged more than 25min, the microstructure of the alloy is similar to that of the electromagnetic stirring Al-Mg2Si alloy without adding P, where the intermittent dendritic segregation distribution of the primary phase Mg2Si appears, and the grains become much coarser, as shown in Fig. 3c.
In the nucleation process of primary Mg2Si phase, the AlP particles will be taken as the crystallization nuclei, and a large number of Mg and Si atoms will accumulate onto AlP particles to form crystal nuclei.
Thus, the b a c Fig. 4 Mechanical properties of Al-Mg2Si alloys with different P contents a hardness; b elongation; c ultimate tensile strength AlP as the heterogeneous particle not only increases the number of the crystallization nuclei, but also decreases the nucleation difficulty of the Mg2Si phase.

Radial forging has a number of essential advantages, among which there are absence of porosity and development of a supposedly stable homogeneous fine-grained structure promoting an increase in technological and operating properties of products.
The following aspects of structure formation in studied rods at different temperatures are considered: - the texture nonuniformity of rods over cross-section; - the effect of radial forging on the phase composition of the Zr-based alloy; - dynamic recrystallization within deep layers due to the inflow of lattice defects; - formation of perfect fine grains due to "shaking" recovery and regrouping of dislocations; - prevalent plastic deformation mechanisms, activated by repeated impact loading and undulatory passing of impulses through the bulk of rods; - absence of recrystallization in studied products by their annealing after radial forging.
The above mentioned rods were investigated by a number of X-ray methods: - the phase analysis, that is determination of β-phase volume fraction Wβ with Nb content CNb; - the determination of average lattice parameters, that is c, a, c/a and unit cell volume V; - the X-ray line profile analysis aimed to determine substructure parameters, among which there are the coherent domain size D, the lattice distortion ε, and the dislocation density ρ [2]; - the texture analysis by direct pole figures (PF) [3].
The formation of a coarse-grained structure, observed by sharp changes of Hµ when passing from one point to another, is a result of recrystallization in a non-optimal variant for the rod's mechanical properties.

The solid phase of cement stone and concrete is mainly characterized by the presence of two structural components – crystalline products in the form of calcium oxide hydrate, tri-calcium hexahydrate, calcium hydro-sulfoaluminate, unreacted grains of cement and aggregate, as well as gel-like products in the form of calcium sub- microcrystals with a variable composition [3].
It is known that this process is influenced by a large number of interrelated reasons: the structure and the pore and capillary size in the material into which the solution penetrates, its physical and mechanical properties, surface tension, viscosity, density, vapor pressure, size and structure of solute molecules, their polarity, ability to form aggregates in solution or interact with the material of the porous structure [6].
It is known that in the cement stone solid-phase system, some part of the cement always remains unreacted in the form of grains surrounded by crystallization and coagulation structures of neoplasms, which can exert its influence upon the structure destruction.
It is shown that due to the hydrophilization of the cement stone surface, the degree of filling the pore space of fine-grained concrete in a 2% solution of glycerin and ethylene glycol is 12-20% higher than in water.
The aggressiveness of polyhydric alcohols increases with an increase in the number of hydroxyl groups in the molecule, the orientation of which during adsorption on a cement stone leads to a greater hydrophilization of its surface.

The average grain size was 27.6nm according to the Scherrer Equation.
It can be seen that the sample consists of particles with grain sizes ranging from 20 to 30 nm, which is in good agreement with the XRD result (Fig.1 (a)).
The results indicate that VOC2O4·H2O is reduced by NH3 at first, and the purity V2O3 was obtained at 500°C for 30 min with uniform grain sizes of 20~30 nm.
Acknowledgements Financial support from the Fundamental Research Funds for the Central Universities (Number XDJK2010C009) and the Key Project of Chinese Ministry of Education (Number 105144).

The number of the precipitates observed in Steel D is 2 times more than that in Steel B.
If the amount of V in the α/γ interphase is doubled due to the grain boundary segregation, the driving force for the formation of VCN becomes 40.4kJ/mol.
The grain boundary diffusion coefficients of V and Cu in Fe are unknown but it is generally said that the difference of the grain boundary diffusion coefficient of one element from the other is small if their balk diffusion coefficients do not differ from each other significantly.
The experimental result showed that the number of the aligned precipitates of Steel D increased in comparison with Steel B.

Results and discussion SEM investigations on the fracture of the sample BT, BLT1 and BLT3 emphasized a coarse and dense microstructure, similar to the undoped BaTiO3, consisting predominantly of large grains with non-uniform shape.
The inhibiting effect of the donor dopant on the grain growth process becomes evident, for the samples with higher lanthanum content BLT5 (Fig.1).
A model structure used for diffraction pattern fitting exhibited space group P4mm (SG number: 99), detailed information about the model structure used is given in [9].
It was identified as tetragonal symmetry, space group P4mm (SG number: 99) for all tested samples.
Burfoot, Grain-size effects on properties of some ferroelectric ceramics, J.Phys.C: Solid State Phys. 7 (1974) 3182.

It is believed that various exchange interactions, structural distortions, cationic disorders and grain boundary effects are primary ingredients for the induction of rich phenomenology in these materials [10, 11].
Table 1 The lattice parameters for the samples with nominal compositions La2/3Sr1/3MnO3: Agx x a=b (Å) c (Å) V (Å3) 0.00 0.10 0.20 0.30 0.40 5.486 5.494 5.503 5.499 5.496 13.374 13.360 13.315 13.357 13.405 348.571 349.222 349.187 349.779 350.653 Fig.1 X-ray diffraction patterns of La2/3Sr1/3MnO3: Agx composites Combined the Bragg equation (1) and the lattice formula (2), grain size of the LSMO: Agx composites could be obtained in table 1
Excellent conductivity of LSMO: Agx composites are due to that metal Ag enhanced the connectivity of grain boundary and improve the crystal quality of samples [6].
Acknowledgements This work is supported by the National Natural Science Foundation of China (Numbers: 50974066 ) and Natural Science Foundation of Yunnan (Numbers: 2009ZC013M).

And wood is the only material that can be used not only as a load bearing and insulating structure but also as auxiliary components, as a raw material for furnishings and as a surface material. [1]In addition to such features as local availability, Strength, workability, naturalness and numerous other superior qualities, timber has three properties that make its use challenging :every single tree is an individual, wood adjusts to the ambient humidity, and its properties are different depending on whether they are measured along or across the grain of the wood.
Annually more than 80 million cubic metres of high-quality timber grow in that area, and felled trees are always replaced by regeneration.[2]It’s predicted that solid timber will be developed and used for a greater number and variety of purposes in the future.
The number of components and the joints between them make designing a timber house a laborious task and the structure vulnerable.[4]Wood surfaces cut across the grain are especially vulnerable to changes caused by humidity, and therefore joints and connections have to be designed with special care to be both aesthetically pleasing and structurally strong.
It is rather a complex and finely-grained entity, in which each building component has its own important function. [6]Wood is not a perfect material and its behaviour is sometimes hard to predict and control.

The grain includes the rift grain, the cross grain and the transverse striation, the rift grain’s flex resistance is the best and the cross grain’s is the second best, but the transverse striation is easy to fracture.
Therefore, stones with cross grains and transverse striations should not be used as hanging load bearing members and materials of stone carving.
In contrast, stones with rift grains are often used as hanging load bearing members and materials of stone carving.
Generally speaking, the number of the apprentices is uncertain, sometimes it is decided by the scale of the project.
In the fixed stone carving societies, several settled men organize the activities; while in the unfixed societies, the number of the participators is uncertain, and they have perfect mutual understandings and common moral standards.