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Cultured cells, both rat calvaria osteoblasts (isolated and characterized according to established methods [4] at population number 3) and rat-skin fibroblasts (purchased from, and characterized by, the American Type Culture Collection; population number 14-16), in Dulbecco's modified Eagle's medium (containing 10% FBS) were seeded (3500 cell/cm2) per substrate and allowed to adhere in a 37ºC humidified, 5% CO2/95% air environment for 4 hours.
The representative scanning electron micrographs of Fig.1 illustrate the materials revealing two distinct morphologies: spherical particles (with diameters in the range or 60-150 nm) on the non-sintered (Fig.1a), and agglomerates that formed both porous (Fig.1b) and non-porous arrangements on the sintered substrates with grain size with diameter in the range 400-600 nm.
Acknowledgements The authors acknowledge the financial support in the USA of the Nanoscale Science and Engineering Initiative of the National Science Foundation under NSF Award Number DMR-0117792, and in Portugal, FCT's project POCTI/FCB/41523/2002.

Quartz sand with a maximum grain size of 2.5 mm was used as aggregate.
It is obvious that the microstructure of the sample with 1% PEG is very similar to the sample with 10% PEG with approximately the same number of microcracks.
Microstructure alone provides little indication of the influence of various polymer dosages on the mechanical properties of AAS mortars but the number of microcracks was not reduced for any of applied admixtures.
Firstly, there were an increased number of calcite crystals in the AAS matrix.

For a number of practical applications, it is essential that carbon nanotubes have a low specific gravity.
To form a multilayer composite compound of the film - polymer, a medium-grained polyester polymer of the HB BODY PRO F 211 brand was used.
Clusters of carbon nanotubes have a low density and strength due to the fact that they contain a large number of pores.
In a number of cases, micro-cracks are visible.

A variety of industrial by products and waste as well as a number of aluminosilicate raw materials have been used as the cementitious components in alkali-activated cements and concretes.
Table 5 Specimen design Test type Specimen size Groups Number of specimen Cube crushing strength test 150 mm×150 mm×150mm 12 3 Drying-wetting cycle test 100 mm×100 mm×100mm 8 3 Flexural-tensile strength test 100 mm×100 mm×400mm 4 6 Specimen production.
It has low activity and fine grain so that it reduces the continuity of the inorganic polymer network structure which affects the strength of the specimens.
Considering the microscopic structural characteristics, ordinary concrete specimen contains a large number of capillary channels so that the structure is not density enough.

Thus, the standard form of PSO could be denoted as: (1) (2) where is called inertia weighting factor and used to better control the scope of the search, R1 and R2 are two independent random numbers selected in each step according to a uniform distribution in a given interval [0,1] and C1 and C2 are two constants which are equal to 2 in this standard version.
The random number was multiplied by 2 to give it a mean of 1, so that particles would “overshoot” the target about half the time.
One approach to reduce the elapsed time is to make use of coarse-grained parallelization to evaluate the design points.
Furthermore, this part of the computational work is scalable, i.e. increasing the number of particles will cause the amount of evaluations to increase proportionally.

Fig1 is Welding joint microstructure filled in different welding materials of 1Cr18Ni9Ti and 2Cr13 steel, it is shown that the grain in HAZ zone is bigger than that in other zone of welding joint, this deduces from welding heat circulation effect[2]; the microstructure of welded joint is column crystal structure, this was rooted in quicker heat dissipation vertical to welded joint.
These samples number is same as follows.
Table 5 Elongation and reduction of area of 1Cr18Ni9Ti and 2Cr13 welding joint filled in different welding wire Number 1# 2# 3# 4# l0/mm 50.00 50.00 50.00 50.00 l1/mm 63.40 54.88 58.73 76.69 δ 26.80% 9.76% 17.46% 53.38% S0/mm 37.40 41.55 41.29 37.64 S1/mm 20.63 38.67 26.71 21.97 ψ 44.84% 6.96% 35.31% 41.63% These data can de compared horizontally on the basis of same experiment, From table5,elongation of welding joint filled in ER308 welding wire is 26.80%, reduction of area is 44.84%;elongation of welding joint filled in H1Cr21Ni10Mn7Mo welding wire is 9.76%,reduction of area is 6.96%；elongation of 2Cr13 martensite stainless steel is 17.46%,reduction of area is 35.31%;elongation of 1Cr18Ni9Ti austenite stainless steel is 53.38%,reduction of area is 41.63%.
Table 6 Strength index of welding joint 1Cr18Ni9Ti and 2Cr13 filled in different welding materials Number 1# 2# 3# 4# σb/Mp 635.70 492.34 846.03 653.70 σs/Mp 4.57 3.34 39.13 3.59 Conclusions (1)The 2mm 1Cr18Ni9Ti austenite stainless steel and 2Cr13 martensite stainless steel plates, by filling in two kinds welding wire, through TIG(DCEP), typical column crystal can be obtained in welded joint, and microstructure of welded joint is lath martensite + residual austenite + carbide

The excessive rare earth content could lead to a large number of rare earth atoms deposited on the surface to form a " active rare-earth atoms stacked layer", and there are a large number of boron atoms adsorbed around layer, so it increase the resistance of boron atoms to diffuse into the surface and decrease the numbers of boron atoms reaching the surface reduce ［3］.
The wear resistance of the surface of the sample with the boronizing optimization, quenching and tempering treatment is higher than the sample with ordinary boronizing, quenching and tempering treatment, this is because the rare earth increase the Fe2B phase nucleation rate, and refine Fe2B phase grain, and improved carbonitriding layer density, increase the thickness of layer, reduce the hole and porous with osteoporosis carbonitriding layer.

A number of groups have investigated the BaO-R2O3-TiO2 (where R means rare earth elements) system on the crystal structure and the microwave dielectric properties systematically.
Compared with BaLa4Ti4O15 which belonging to trigonal system [9] and has been studied widely even by templated grain growth (TGG) method[10], there is no report of NaO-R2O3-TiO2 system, to the best of our knowledge.
It possesses the following unit-cell lattice parameters: a=b=2.1616 nm and c=1.0536 nm, the number of molecule per crystal lattice: Z=12 and the theoretical density: ρ=5.23 g/cm3.
NET possesses the following unit-cell crystallographic lattice constants: a=b=1.9680 nm and c=1.1515 nm, the number of molecule per crystal lattice: Z=12 and its theoretical density: ρ=5.81 g/cm3.

Introduction Although there are a large number of ABO3 simple perovskite, when one or more cations of the structure are replaced by other ones generates a group of compounds known as double perovskite, AA'BB'O3 or A2BB'O6.
This method allows to obtain material with high chemical and structural homogeneity, containing grains with controlled morphology and size, and high purity [6,7].
The synthesis performed with less air flow (3 L/min) and higher temperature (900 °C) showed a greater number of particles agglomerated and an increase in crystallite size to 14 nm.
All XRD diffraction patterns exhibited only a set of diffraction lines ascribed to SrTiO3 single phase powders, which were identified from the JCPDS card number 35-0734 with cubic symmetry and space group Pmm (221).

Because of quick setting and hardening, it can construction after making floor material in number hours.It can bond firmly with various basements[2~3].This mortar has low shrink rate,high compressive strength and good abrasion resistance.So it is the development trend of ground leveling materials.
Table 2 The factor level orthogonal test Number A [C:S] B [Mx] C[Heavy calcium%] D [CA%] 1 1 2.2 10 5 2 1.33 2.5 20 10 3 1.67 2.8 30 15 cementing material:900g,water-cement ratio:0.4,Water reducer:0.6% Table 3 The result of orthogonal test Number A B C [%] D [%] Fluidity [mm] Flexural strength of 28d [MPa] Compressive strength of 28d [MPa] 1 1 2.2 10 5 167 9.10 45.35 2 1 2.5 20 10 127 8.39 42.48 3 1 2.8 30 15 80 7.30 39.61 4 1.33 2.2 20 15 60 10.36 59.45 5 1.33 2.5 30 5 150 6.82 36.77 6 1.33 2.8 10 10 60 7.34 44.74 7 1.67 2.2 30 10 75 6.93 40.97 8 1.67 2.5 10 15 80 9.80 52.15 9 1.67 2.8 20 5 90 9.24 43.73 Table 4　Intuitive analysis of fluidity of mortar Fluidity of mortar [mm] K1 K2 K3 374 270 245 302 357 230 307 262 305 407 262 220 K1/3 K2/3 K3/3 124.7 90 81.7 100.7 119 76.7 102.3 87.3 101.7 135.7 87.3 73.3 R 43 42.3 15 62.4 Table 5　Intuitive analysis of flexural strength of 28d Flexural strength of 28d [MPa] K1 K2 K3 24.79
It can make Ca (OH)2 priority into nuclear near of make heavy calcium carbonate particles.Most Ca (OH)2 growth in heavy calcium carbonate surface, and not in specific location forming local large crystal.Ca (OH)2 grain refinement, in favor of interface bonding.