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The porous structure of iron ore shows promising features for tar vapor decomposition and carbon storage sites [5].
Raman spectroscopy analysis as illustrated in Fig. 4 was carried out to analyze the amorphous structure of the carbon [14].
This amorphous structure of the infiltrated carbon reflects the reactivity of the carbon during direct reduction process in which the higher sp3 shows the most reactivity.
K., & Li, L., Characterization of Amorphous and Nanocrystalline Carbon Films, Materials Chemistry and Physics. 96 (2006) 253–277
Materials Chemistry and Physics. 101 (2007) 235-240.

The O-MWCNTs were observed for the destroyed structures by using field emission scanning electron microscope (FE-SEM, JEOL-6335 F, Japan).
In Fig. 1(a), it was observed that after the oxidation by a mixture of 96% concentrated sulfuric acid and 65% concentrated nitric acid, the structure of the MWCNTs was completely destroyed.
Fig. 1(b) shows that the structure of the MWCNTs was partially destroyed after they were oxidized by a mixture of 52% diluted sulfuric acid and 30% diluted nitric acid.
Fig. 1(c) shows that the 65% concentrated nitric acid slightly destroyed the MWCNTs’ structure.
However, most of them could maintain their structure.

At 883oC, the crystal structure undergoes a transformation from a (hcp) to b-phase, a body centered cubic structure.
Commercially pure titanium is made up mostly of the a-phase structure.
Oxygen atoms occupy the interstitial sites in the crystalline structure, straining the lattice in the process.
The chemistries of the various milled samples were evaluated in terms of overall contaminant pickup.
Powder Chemistry Sample Armstrong CP-Ti O (%) 0.181 N (%) 0.008 H (%) 0.004 C (%) 0.007 Fe (%) < 0.001 Na (%) 0.033 Table 5.

Thus it ensures that the entire water system can withstand the stress due to the structure deformation caused by temperature and wind pressure variation, it could also avoid the structural damage caused by severe weather[1].
It can also used on a variety of old and new buildings or structures.
What is more, the formation of the physical chemistry point will increase with an increase of the amount of cement dosage, which will result in the increased tensile strength and the decreased elongation.
This may ascribe to the layered structure of talcum powder.
This structure is beneficial to improving elongation, however, the plasticity of kaolin is better.

Dynamic Stress Concentration Analysis of Multiple Circular Cavities near Multiple Semi-cylindrical Alluvial Valleys Huiwen Wang1, a, Zailin Yang2, b and Huanan Xu2, c 1Department of Materials and Chemistry Engineering, Heilongjiang Institute of Technology, Harbin 150050, China 2College of Aerospace and Civil Engineering, Harbin Engineering University, Harbin 150001, China ahuiwenwang9@sohu.com, byangzailin00@163.com, chntiger_86@126.com Keywords: SH-waves, Multi-polar coordinates, Complex function, Semi-cylindrical alluvial valley, Circular cavity, Dynamic stress concentration factor.
Introduction Dynamic response of local terrain on the nearby shallow structures under incident SH-waves, as one of the fundamental issues on earthquake engineering and underground structure seismic along with anti-explosion theory research, has important theoretical significance and application value.
Numerous surveys on dynamic analytical solution on shallow buried structure under SH-waves have been reported [5-6, 8].
Complex-variable function method is used widely to solve the scattering problems of SH-waves by a surface structure.
The dynamic stress concentration factor around the shallow buried cavities can be written as , (13) where is the stress around the outer boundary of the circular lining structure,stands for the largest amplitude of the incident stresses, .

Cubic perovskite structures are observed in both the calcined pow- ders and dense ceramics.
The homogenous structure is observed with the small grain size (1 ~ 2 µm).
Considerable high dielectric constant of the present ceramics can be explained by the following defect chemistry equations: xSrO TiOSrPbxPbO SrTiO 3x1x 3 + →+ − (1) ↑++ → + ++ − −− − 2 3 3 y 4 y1yx1yx 3/2 3x1x O 4 1 yPbO)OTi(TiSmSrPb ySmO TiOSrPb (2) In the calcined powders, Pb ions replace some Sr sites of SrTiO3.
Then, the grain boundary capacitors structures form and considerable high dielectric constant is obtained.
The homogenous microstructure with the small grain size (1~2µm) is observed in the specimen with the cubic perovskite structure, and CuO is found to accumulate at the grain boundary.

Polyisobutylene (PIB) is a vinyl polymer made from the monomer isobutylene by cationic vinyl polymerization, which is similar to polyethylene and polypropylene in structure, except that every other carbon is substituted with two methyl groups[2].
The initial adhesion was characterized by a Electronic tensile test machine to choose the optimal PIB content, the functional groups in PIB modified PU structure were analyzed by FTIR, the density of foams was studied by a electronic density scale[4].
The spectrum contained peaks associated with the N-H stretching vibration (1540cm-1), C=O blending vibration (1690cm-1) in the urethane group, the stretching vibration of isocyanate group (2271cm-1) and the stretching vibration of methyl group (2940cm-1) in the structure of polyisobutylene.
IR spectrum of PIB modified PU foam with PIB content of 30% Density test results of PIB modified PU foams Fig. 3 Density of foams with different PIB content As shown in Fig. 3, it was obvious that with increasing of PIB content, the density increased, indicating the foam structure got denser.
[4] Qiang Fu, Hong Tan, et al, SURFACE STRUCTURE AND BULK PROPERTIES OF FLUORINATED POLY(ETHER URETHANE)S AND POLY(ETHER URETHANE) BLENDS,J.

Domestic scholars generally use chemical or mechanical test method to test kenaf fiber and composite materials, relation of composition with performance [3-6], but few studies on using infrared spectroscopy analysis kenaf fiber and its composite structures.
Microscopic morphology of composite material was also studied by SSX-550 scanning electron microscope, and the structure and their chemical reaction relationship of kenaf fiber and of PE was researched and discussed combining with composite material’s mechanical property.
There are many absorption bands, and its frequency, shape, strength are closely related with molecular structure.
As showed in Table 1, the structure of kenaf fiber changed a lot after KH-550 silane coupling treatment.
Ryan:Handbook of analytic Chemistry(second edition) Infared Raman Spectrua(Press of Science, Beijing, 1991),in Chinese

The small number of movements of the resulted pallet changer mechanism helps the design engineer to choose the most simple structure which reflects positively in the production cost.
The tree-graph method comes from one of the mathematics disciplines and was used successfully in resolving practical issues from different areas of research such as: physics, chemistry, economy, etc.
This method consists of following several steps, begging with the representation of the machining center structure using tree-graphs till obtaining the final optimal configuration of the pallet changer mechanism.
The fifth step of the designing process estimates the allocation of certain edges and joints in the structure of existing tree-graphs and afterwards applying certain specific constraints to the analysed mechanism.
Thus, in the considered case, the design requirements are: - in the structure of the tree-graph there are 3 joints between the machining centre`s table and the spindle; - the automatic pallet changer mechanism is associated with a terminal edge; - the machining centre`s table is also associated with a terminal edge; - between the machine bed B and the table there is a translation movement.

This technique has the great advantage over sol-gel spin-on processing in that it is suitable for nonplanar structures, including nanotubes and nano-wires.
Introduction Our research focuses both on the fundamental physics, chemistry and material science of thin films functional oxides which are deposited here in our lab, and also on extrinsic effects caused by novel geometries and processing required for integration of such oxides into commercially available microelectronic devices.
We have also prepared [3D] FE structures in the form of tubes [4].
FeRAMs) and microelectromechanical devices (MEMs): Data Storage (FE-response) • High density 3D FeRAMs c.f.existing planar structures • High aspect ratio coatings (trenching) for DRAMs MEMs (piezo-response) • Ink jet printers • Drug delivery implants • Micropositioners/movement sensors • Composites Fig 2 Ferroelectric hysteresis of a 600 nm thick SBT film annealed at 800 °C.
Functionally graded planar structures LG Electronics Corp. in Korea has utilized the misted system deposition system described above for DRAM capacitor deposition, with (Ba,Sr)TiO3 as the capacitor dielectric.