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Dave 3 1 Korea Institute of Geoscience and Mineral Resources, Daejeon, 305-350, South Korea 2 Department of Chemistry, Sungkyunkwan University, Suwon, 440-746, South Korea 3 Department of Chemistry, Southern Illinois University, Carbondale, IL 62901, U.S.A.
Their structures, pore sizes, surface areas, degrees of stability, degrees of solubility, and other properties were examined and compared.
XRD(X-ray diffractometer, Rigaku, D/MAX 2200 ultima) was used to measure the pore size and structure under a scanning rate of 1 degree/min.
The size and structure of a pore depend on the kind of solvents and surfactants that had been used, and on the concentration of the surfactants.
The XRD peak of the sample without OMC is sharper and has a larger 2θ value than the other one; this means that its pore is distributed with an ordered structure, and that it has a relatively small size.

The XRD result showed that alginate addition did not change the HAp-Zn structure and phase.
A previous study confirmed a high crystallinity could be achieved through microwave assistance; it could provide a stable structure [3].
To evaluate the alginate existence whether influencing the structure and phase of HAp-Zn, the XRD was performed.
It indicated that alginate addition did not affect the structure and the phase of HAp-Zn.
Khatamian, Investigation of Structural Properties of Hydroxyapatite/Zinc Oxide Nanocomposites; an Alternative Candidate for Replacement in Recovery of Bones in Load-Tolerating Areas, Materials Chemistry and Physics 226 (2019) 169–176

Through the test, the influence law of admixtures on impermeability of C30 mass concrete were obtained, and at the same time the better mix proportion of C30 anti-seepage mass concrete used in bridge anchor structure was recommended.
The mass concrete of bridge anchor structure used in the study was constructed through pump, of which designed strength is C30 and designed slump is 180~220mm.
For this reason, the structure of hardened cement paste and interfacial transition zone will be more compact, therefore it can improve the post-strength of concrete strength[7].
At the meantime, pozzolanic effect generates a lot of finer crystal structure, thereby increases the strength of cement stone.
Vol. 3 (2013), P.99-102 (In Chinese) [6] Baert G and Driessche I V: 12th International Congress on the Chemistry of Cement.

This method was applied to refine the grain structure to ultrafine dimension.
The deformation allows for the formation of the equiaxed structures.
The Al grain/subgrain structures are complex.
The dislocation cell structures were found inside larger grains.
Richert, Effect of large deformations on the microstructure of aluminium alloys, Materials Chemistry and Physics, 81, (2003) 528-530

For example, appropriate Sc and Zr additions have a significant impact on the grain structure of 2xxx alloys and thus on performance.
Further gains of a similar magnitude in component weight and cost can be achieved by applying new technologies and new design solutions to metallic structures.
Such additions can thus be used to obtain a beneficial unrecrystallized structure for 10-40 mm plate whilst improving toughness compared with the conventional Mn-containing 2024-type alloys.
The effect of the three different dispersoid-forming additions (Mn, Zr, and Zr+Sc) on the grain structure of these plates, illustrated in figure 2, can be summarized as follows: the conventional alloy (2x24 Mn, corresponding to a 2024-type chemistry) shows a partially recrystallized microstructure.
Secondly, there is still potential in the improvement of grain structure, via both grain refining processes and grain structure control.

Stability of the nanoparticles after reuse was verified by the close match of XRD patterns of the pure and reused CAO which show no significant changes in its crystal structure.
The XRD patterns of pure CAO and CAO after two consecutive cycles (Fig. 9), show no significant changes in the crystal structure of the adsorbent, viz., CAO, attesting the stability of the nanoparticles.
Stability of the nanoparticles was verified by the close match of XRD patterns of the pure and reused CAO which show no significant changes in its crystal structure.
Bian, Formation and characterization of monolithic nanoporous copper by chemical dealloying of Al− Cu alloys, The Journal of Physical Chemistry C, 113 (2009) 6694-6698
Foletto, Rapid and facile preparation of zinc ferrite (ZnFe2O4) oxide by microwave-solvothermal technique and its catalytic activity in heterogeneous photo-Fenton reaction, Materials Chemistry and Physics, 160 (2015) 141-147

Fe 3+ ions, become part of the crystal structure, dimensions of the unit cell change.
In the course of our experiments strength properties were determined to monitor fracture formation - self-healing processes in the structure.
The Al2O3 used were produced in the Laboratory for Silicate Chemistry and Materials Science Ltd. at 99.99 % (m/m) purity, 5.4 m2/g specific surface and 5 µm main particle size.
Electron microscope image of sample ATF5 after 5 cycles (Figure 4) shows a cut-up structure and the addition of Fe2O3 did not eliminate micro-fractures present in AT.
The electron microscope image taken after the 40 th cycle (Figure 6) clearly shows the repeated thermal shocks were destructive to the structure.

Clearly, the phase transition will lead to a remarkable change in the crystal structure, electrics, magnetics, ionics, and thermal conductivity in Ag2Se [2-8].
It is also found that tetragonal Ag2Se was improperly assigned to superlattice structured Ag2Se [13].
The cubic structured nanocrystals tend to grow into a polyhedral shape, like noble metals (e.g., Ag, Au) [14].
The phase structure and purity of the Ag2Se products were examined by room-temperature (25 °C) XRD analysis.
The tetragonal structure is a low-temperature polymorphic phase for Ag2Se, besides the low-temperature orthorhombic and high-temperature cubic structures [1-4, 9-12].

The deep pore is usually perpendicular to the wafer and the pores connect to each other to form 3D structure by further etching.
However, the similar etching processes may result in similar structure.
The shift could be explained as a result of phonon confinement in nanocrystalline silicon inside the porous structure, consisting with the TEM analysis [12].
The porous structure is composed of nanocrystal grains and a small amount of amorphous silicon.
This general approach will pave a new pathway for the further extensive study of the new structures of porous silicon.

Self healing technology can be used to repair the cracks in a concrete structure automatically, resulting in an improvement of concrete structure performance[2].
Several technologies were employed in structure characterization and property testing for the material application, including XRD, gas adsorption method and pore size analysis, etc.
The data of pore size and surface area indicate that the application of microcapsule in cement composite can improve the durability and impermeability for concrete structure [8].
“self-healing of advanced composite structures using hollow glass fibres”.Smart Mater.
INRERNATIONAL CONFERENCE ON DURABILITY OF CONCRETE STRUCTURES, 195-204, November Hangzhou, China