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Our aim is to use DFT to evaluate the activation of CH4 on the Fe or Ni bilayer modified α-Al2O3(0001) catlayst to shed light onto the electronic structure of the catalyst upon CH4 adsorption and dissocation.
To evaluate the electronic structure of the catalyst local density of states (LDOS) were performed to provide information how atoms contribute to certain electronic states in the energy spectrum.
Figure 1 a) Schematic diagram of the M1M2/α-Al2O3(0001) model catalyst and the b) geometry optimized structures of CH4 or CHx(x=1-3)+H adsorption on the Ni or Fe modified α-Al2O3 surface.
Energy analysis suggested that the stability of the system is due to the mutual relaxation effects of the catalyst structure and the C-H bond of CH4 closest to M1.
Ji, The Journal of Physical Chemistry, 1996, 100, 2330-2333.

XRD reveals that the nanostructures contain an inhomogeneous crystalline structure.
For boron carbonitride nanotubes (BCN NTs), previous studies have revealed that the anticipated electronic and mechanical properties both depend on their radii and the chemistry related of heteroatomic counterparts [9, 10].
Detailed structural and compositional analysis indicates that the as-grown boron carbon nitride needle-like nanostructures have an inhomogeneous crystalline structure.
Finally, a thermal etch the diffusion layer via subliming BCN results in the needle-like structure (step c).
Therefore, the codeposition of the inhomogeneous structure and amorphous domains indicates that the thermal factor as the structural subliming and grains grown play a key role in the formation of the BCN needle-like nanostructures during the PVD growth.

Using of Impact-echo method from the group of acoustic methods for non-destructive testing allows detection of micro-defects in the structure of the material [4] which allows monitoring the condition of internal structure.
This method appears to be a convenient method to monitor the building structure condition, defect detection, identification and location which are constituents of the technical condition diagnosis [5].
Owens (eds.), Proceedings of the 11th International Congress on the Chemistry of Cement, Durban, South Africa, 2003, 1878–1888

Synthesis of carbon spheres with controllable size distribution by chemical vapor deposition Leishan Chen1,a and Cunjing Wang1,b College of Chemistry and Chemical Engineering, Xinxiang University, Xinxiang 453003, China aemail: chenleishan@yahoo.cn; bemail: wangcunjing@126.com Keywords: carbon spheres; nanostructures; chemical vapor deposition; anodic aluminum oxide template Abstract Carbon spheres were synthesized by chemical vapor deposition.
Introduction The unique subtlety in bonding configurations that results from carbon’s ability to employ almost any conceivable combination of sp, sp2 and sp3 hybridization in a wide range of materials results in an immensely diverse range of structures and morphologies with extensive technical applications.
And the discoveries of fullerenes [1] and 1D carbon nanotubes [2] have resulted in the exciting developments in the nanoscience and nanotechnology of carbonaceous structures [3].
The AAO template was placed at Zone B to prevent the collapse of the porous structure of AAO at Zone A and the insufficient catalytic activity at Zone C.

Alloy 600 and Alloy 182 have been known to be very susceptible to a stress corrosion cracking (SCC) in the primary water side environments, and the SCC susceptibility is considerably dependent on the metallurgical factors such as the grain boundary chemistry and a precipitation [2].
From the analysis of the diffraction patterns such as Fig. 2(b), the precipitates found in the base metal were identified as Cr7C3, having a pseudo-hexagonal structure with a = 1.398 nm and c = 0.452 nm [4].
They had a cube-cube orientation relationship such as {100}matrix//{100}ppt, <100>matrix//<100>pot with one grain, and their crystal structure was face-centered-cubic (fcc) with a lattice parameter of 1.065 nm.
It was revealed experimentally from the TEM analysis that their crystal structure was fcc with a lattice parameter of ~ 0.448 nm.

Although the Face-Central-Tetragonal (FCT) structure of TiAl is very similar to the Face-Central-Cubic (FCC) structure, the number of independent slip system in the former is far less than in the latter, since the c/a=1.02 in TiAl[2, 3].
Liu: Materials Chemistry and Physics Vol. 42 (1995), p77

Body centered cubic (BCC) structure alloys are obtained in some of the Mg-Ni-B compositions after the starting mixtures of raw elements were ball milled for 200 h.
Mg50Ni45B5 and Mg48Ni48B4 alloys after ball milling are with single BCC structure, which is confirmed by electron diffraction patterns.
The peak positions, which are indexed to BCC structure, are marked in the patterns.
The inset in Fig. 2 is the selected area electron diffraction pattern of the BCC alloy, the diffraction rings are indexed to BCC structure.
Wiswall: Inorganic Chemistry Vol. 7 (1968), p. 2254 [2] J.

Synthesis of NiCu Alloy Nanoparticles by Arc Plasma Evaporation Lixin Li 1,a, Zhongjuan Yang1 and Ming Li1 1College of Physics & Chemistry, Henan Polytechnic University, Jiaozuo, 454000, China aemail: lilixin@hpu.edu.cn Keywords: NiCu alloy nanoparticles，Synthesis，Arc plasma evaporation，Agglomeration Abstract.
The experimental results indicated that the crystal structure of the powders is face centered cubic structure, the same as the bulk raw materials.
The crystal structure was characterized by X-ray diffraction (XRD).
The five strong peaks correspond to (111), (200), (220), (311), (222) planes of NiCu alloy powders, which can be perfectly assigned to fcc (face centered cubic) structure, the same as the bulk raw material.
The powders are with face-centered cubic structure, the same as the raw bulk materials.

Experimental Details The subject of research was poly-N-methylallil-5-vinyl tetrazole (MPVT-A) having the following chemical structure: Dimethyl phthalate was used as plastifier.
Thus, by changing the chemical structure of the modifier, it is possible to trace the way of changes in the physical properties of the tetrazolecontaining polymers, which ultimately enables modifying the viscoelasticity parameters in the given direction, e.g. to increase or decrease the shear modulus in the vitreous state, to change the glass temperature and the area of transition from the vitreous state into the highly elastic state.
Summary Thus, without changing the chemical structure of the modifier, by changing only its concentration it is possible to influence on the cooperativity in the glass process.
Research into Processes of Structuring of Tetrazole Polymers with Various Hardening Systems. // News of Higher Education Institutions, Series of Chemistry and Chemical Technology, 2006.– v.49.

Introduction Concrete durability depends largely on its complex submicroscopic structures and the level of possibility of harmful gases or ions’ entry into concrete [1].
Thus the aim of study is to explore the effective initial steam curing duration and water curing time of pre-cast concrete with relative lower water/binder ratio by analyzing the effects of curing parameter on submicroscopic structures of concrete with modern analyzing techniques.
(a) Reference sample (b) 5h-duration (c) 14h-duration (d) 24h-duration Fig.2 Effects of duration of steam curing on macroscopic pore structures The initial water-curing time has great influence on the later performance of concrete, especially for concrete with low water-binder ratio [7-8].
Structure and Performance of Cement Concrete[M].
Chemistry of Cement and Concrete [M]. 3rd ed.