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College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, China aemail:klmdmj@126.com Keywords: density functional theory(DFT); atomic layer deposition(ALD); Al; reaction mechanism Abstract: Using H2 and Al (CH3)3(TMA) as precursor, we investigated the atomic layer deposition mechanism of the metal Al on Si (100) surface by density functional theory.
Geometry structure will use full optimization method without any restrictions, calculated on the basically frequency analysis to optimize the structure, each stationary point to verify the reaction potential energy[6,7].
Products formed, the distance between two carbon atoms Al and little difference from the structure stable, Al and Si atoms is between 2.47122nm.
The reaction is then formed in a nearly planar four-membered ring structure, the four-membered ring structure composed of silicon - aluminum atoms.
The reaction is then formed in a nearly planar four-membered ring structure , the four-membered ring structure composed of silicon-aluminum atoms.

This method has provided information about the structure of the polymer.
FTIR and NMR were used to examine the structures of polymethylvinylsiloxane.
Each peak is assigned for its specific chemical shift of polymer structure.
The structure of PMVS has been confirmed by FTIR and NMR.
Brook, Silicon in Organic, Organometallic and Polymer Chemistry.

Chloride ion penetration and freezing and thawing damage are the two main factors that affect the durability of concrete structures.
As a matter of fact, concrete structure in the applications always suffers from all kinds of loads, such as dynamics, temperature, chemistry and restrained shrinkage [1,2].
Undoubtedly, the results of this paper have great significance in the durability design and the life prediction of concrete structures.
As we all know that the micro-pore is the important compositive part of the micro-structure of concrete, to some extent the change of porosity can reflect the change of micro-structure inside the concrete.
Thus, for the concrete structure in the severe environment, we should well consider the combined effects of loading and environment and well control the amplitude of the service load when we design the carrying capacity.

The black areas (2) were identified to represent the free graphite that remains at the grains boundaries of the sintered structures.
A homogenous distribution of copper and oxygen in composite structure was noticed.
The iron was distributed all over material structure, excepting the barium segregated areas.
Some traces of both nickel and barium carbonate were still noticeable in the structure of the sintered iron-based composites.
Results of nano-scale modeling, Nanosystems: Physics, Chemistry, Mathematics 2 (2011) 58-64

Xiong 1∗ 1 Department of Materials Science and Engineering and 2 Department of Chemistry, Xiamen University, Xiamen 361005, China Keywords: Microwave ceramics, ZnNb2O6, MnCO3 doping Abstract.
The crystalline structure of ceramic body was analyzed by XRD.
The dielectric properties of ZnNb2O6 ceramics with the columbite structure (see Fig.1), have been investigated by Maeda et al [2].
The sintering behavior, crystalline structure and microwave dielectric properties of ZnNb2O6 added with MnCO3 were investigated.
The crystalline structure of ∗ Corresponding author.

The article examines the change of the slip-line field’s structure with the help of numerical simulation (FEM) in the case of hard turning by gradually decreasing the tool rake angle.
However, the changing of the tool rake angle also changes the structure of the slip-line field.
The slip-line field structure formed during cutting with geometrically defined tool-edge has been studied by numerous researchers.
Significant results have been achieved in the research of slip-line field structure by Oxley [18], Zorev [19], Fang [20], Dewhurst, Kudo, Johnson and Usui, etc. [21-23].
Hungarian Journal of Industrial Chemistry.

Recently, morphologycontrolled fabrication and self-assembly of the nanoscale building blocks into complex structures have been the focus of significant interest in materials chemistry and device fabrications [4-6].
However, there are seldom reports on the synthesis of three-dimensional structures via the assembly of two dimensional nanosheets as the building blocks.
It can be seen that the as-synthesized β-Ni(OH)2 samples exhibit microsphere structure with a diameter range of about 6 μm, as shown in Fig. 2a.
Some incomplete microspheres clearly display the microsphere with hollow structure as indicated by arrows in Fig. 2a.
Fig. 2a further reveals that β-Ni(OH)2 microsphere has porous structures due to the congregation of microplates / microsheets.

The Synthesis of novel chiral organic light-emitting material: 2R,3R-di(tert-butanesulfiny)Thiophene ZHUANG Xiaoxiaoa, SUN Xiaoxiab*, Li Licand Li Yingchund Jiangxi Key Laboratory of Organic Chemistry, Jiangxi Science and Technology Normal University, Nanchang 330013, People’s Republic of China azhuangxiaoxiao1987@163.com; bsunxiaoxia77@126.com; clilyer2002@163.com; dlyc8751902@163.com; Keywords: 2,7-dibromo-9,9′-spirobifluorene, organic light-emmitting, chiral t-butyl-t-butanesulfinate, 2,3-di(tert-butanesulfiny) thiophene Abstract.
The spiro-annulated structure caused by the 9,9′- disubstituted fluorene skeleton is of significance in polymers for optical use.
We envisioned that polymers with this structural feature can be served as an alternative candidate with not only high refractive index originating from the fluorene skeleton but also low birefringence depending on the perfect C2-symmetry of the molecular structure.
Scheme 1 The structures of the chiral organic light-emitting materials Experimental Section Characterization. 1H NMR and 13C NMR spectra were collected on a Bruker AM-500WB spectrometer in chloroform-d as solvent and tetramethylsilane (TMS) as the internal standard.
Results and Discussion Synthetic Design Scheme 2 displays the structures of the materials used in this study 2,3-bis(tert-butylsulfinyl)thiophene 1.

The superhydrophobicity of a solid surface strongly depends on both the low surface energy or chemistry and the surface roughness.
Scanning electron microscopy (SEM, Sirion 200, and 20 kV) was used to characterize the surface structure and morphology.
It was found that the size of the porous structures is in the range of 100-150 nm, similar to surface papillate size of the natural lotus leaf.
According to the SEM images shown in Fig.3 and Fig.4, the WCA depends on the surface density of the porous structures and nonaparticles formed.
It is also found that the WCAs are related to the nanoparticles on the surface of the porous micro-structures.

All samples were characterized using X-ray diffraction (XRD, Bruker D8) in order to determine the formation of PZT perovskite structure.
All samples that sintered in different durations show pure single phase and matched the standard Inorganic Crystal Structure Database (ICSD) in X’pert HighScores Plus software (ICSD File No. 98-007-6143).
As the result, the crystal structure was improved and single phase of PZT were observed.
Besides, there are no structures changes have been observed indicating that increasing the sintering temperature is not able to influence in inducing a structure change for all the samples.
Sleight, Journal of Solid State Chemistry, 151 (2000) 323 [3] Cao, L.