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The crystal phase structures of ZnO were characterized by X-ray diffraction (XRD, Dmax-rB).
The fig.2(a) clearly shows that the grain of pure ZnO is six-prism rod-like structure.
According to the analysis of XRD and TEM, ZnO grains are six prism rod-like or hexagonal structures.
Chen: Journal of Physical Chemistry C Vol. 111 (2007) p.13398-13403 [10] J.
Sun: FP-LMTO study for electron-structure of ZnO and its defects (PhD.

Flake-like structures with the size of 100nm were formed on top the micro-porous MAO treated Mg alloys.
As the air trapped inside these nano-size structures is able to support the water drops as shown in Fig 2 (b) below, these nano size structures contribute to the hydrophobic behavior of such surfaces.
As explained in Fig 2, the increase of water contact angle is partly attributed to the nano-structures formed during eching.
Nano-size flake-like structures were achieved on top of MAO surface using alkaline etching.
Wang, et al., “Construction of superhydrophobic hydromagnesite films on the Mg alloy”, Materials Chemistry and Physics, 129 (2011) 154-160

The pioneering research [2-4] showed that the solid-state nanopores have certain advantages over the biologically ones, including the controlled diameter, the various surface chemistry modification and the long-term stability.
Free-standing SiN film The structure of the silicon nitride membrane is given in Fig. 1.
This structure can protect the 100 nm thick silicon nitride membrane and improve its stability.
Fig. 1 The structure of the silicon nitride membrane Experiment results and discussion A FEI Strata 201 FIB system was used in all experiments.
Shixing Jia for his assistance in fabricating the structure of silicon nitride membrane.

Different methods have been studied extensively to improve the cyclic performance of silicon, There are some main methods: 1) changing physical appearance, such as decreasing the size of the material. 2) Synthesizing the composite materials based on silicon by solution-combustion route [6], vapor deposition method [7-8], HEMM and so on. 3) Synthesizing special structures, such as nanowire [9-11], core-shell structure [12-13] and spherical structure [14-15].
Gao, Core-Shell Material for Lithium Ion Batteries [J].Progress in Chemistry, 20(2008) 771-777
Lu, Synthesis and electrochemical performance of ball-in-ball structure LiFePO4/C [J], Battery Bimonthly, 43(2013) 136-138

Introduction Infrared spectroscopy is a useful tool for identifying material and analyzing the structure of matter and studying the interactions between the molecular and the interactions within molecular, so infrared spectroscopy instrument has become one that has been widely used in chemical analysis and biological component analysis[1-3].
Temperature-controlled chamber is a box-like structure, which is closed but there are two holes on its wall, the wall of which is made by insulation material so can avoid excessive heat loss and not affect the temperature-controlled effect and the performance and measurement accuracy of infrared spectroscopy.
Protrusion column Fig.1 Internal structure of variable-temperature box A pre-value of temperature is manually set for the sample waiting for measurement, and the temperature-control circuit which provides automatically electric power to the heater and the air in box is heated.
The Technical Realization of Variable-Temperature Box Temperature Figure 1 is the internal structure of variable-temperature box.
[3] Xiaoli Chu, Hongfu Yuan and Wanzhen Lu: Progress in Chemistry Vol. 4(2004), p. 528–542,in Chinese

Yeung1,f 1 Department of Chemistry, Materials and Forensic Sciences, University of Technology Sydney, P.O.
Equal channel angular extrusion is an innovative technique developed in the former Soviet Union for manufacture of submicron- and nano-structured bulk metallic materials.
Heat treatment was applied to modify the cast structure from a dendritic structure to an equiaxed α + β phase structure.

The plasma produced in the course of high voltage pulsed discharge will make modifications on the material surface and the effects include cleaning away the surface impurities, surface sculpture, surface cross-linking and new chemical structure formation [4].
After the surface treatment of plasma, free radicals are generated at the material surface and the specific functional groups are formed by the surface reaction and the cross-linking structure layer is formed.
Some people think that the activity of solid phase catalyst is determined by the chemical phase composition, crystal structure and the activated specific surface area[7].
And it makes more holes and destroys the crystal structure.
Progress In Chemistry.

So crystallization is good, crystalline phase is relatively simple, crystal structure is relatively complete of Mg/Al hydrotalcite can be prepared when the Mg/Al atomic ratio of 2:1 and 3:1.
TG-DTA diagram can be further confirmed hydrotalcite structure, to understand the process of thermal decomposition of hydrotalcite.
As known of TG-DTA of Mg(OH)2, all of the structure water releasing and transform Mg(OH)2 into MgO, reaction equation as shown below: Mg(OH)2→MgO+H2O. (1) weight loss of 31% through theoretical calculation, it is very similar to 32.97%, that indicates hydrotalcite has been decomposed into MgO.
Fig. 3 Thermal behavior of HT-3 Conclusion Mg/Al hydrotalcite can be prepared with good, relatively simple crystalline phase, complete crystal structure when the Mg/Al atomic ratio of 2:1 and 3:1; HT-3 has the best crystallization of MgO after calcined at 500oC; Hydrotalcite has decomposed into MgO at 443oC, so we can confirmed the 500oC as the calcine temperature to prepare catalyst support.
Handbook of Chemistry and Physics, 77th ed.

Because of peculiarities in structure, it exhibits special infrared absorption properties, possessing the broad application perspective[4-6].
Fig. 3 The relationship between grain size and wavenumber of MgO Table 1 Infrared absorption peak position Sample No Mg-O vibration adsorption bent (cm-1) Mg(OH)2 Molecule Vibration(cm-1) O-H benting Vibration(cm-1) O-H Stretching Vibration of (cm -1) 1# 400~582.426 1440.636 1631.563 3461.769 2# 400~592.069 1448.350 1631.563 3442.483 3# 400~609.426 1430.993 1629.635 3454.054 4# 400~611.354 1452.207 1629.635 3457.912 5# 400~617.140 1469.564 1631.563 3446.340 6# 400~619.068 1457.993 1629.635 3450.197 7# 400~621.131 1477.278 1630.171 3450.197 8# 400~631.153 1460.582 1630.320 3450.127 9# 400~603.640 1457.993 1629.635 3442.483 10# 400~601.711 1457.993 1643.135 3454.054 11# 400~593.997 1457.993 1631.563 3448.269 12# 400~575.562 1457.993 1630.127 3463.697 The conclusion can be acquired by the analysis above: (1)Overall speaking, the infrared absorption peaks of nano-MgO is wider than conventional MgO, namely the ability of absorption increased and the fine structure decreased even disappear
Note that in the nano-materials, there are lots of structures similar to one-dimensional quantum chain, despite the complicated shapes of nano-materials.
With the same method, we can discuss the structure in which the energies of both the terminal sites are fluctuated.
On the synthesis and optical absorption studies of nano-size magnesium oxide powder[J] .Physics and Chemistry of Solids.

Among these methods, the most feasible method to modify the structure of photocatalyst is by doping with nonmetal [6] since it would narrow down the band gap [7] besides being stable [8], inexpensive and non photo corrosive [9].
This might be attributed to combined effect of the phase structure, particle size and the component existed in the photocatalyst.
Theoretically photocatalytic activity is affected by many factors such as phase structure, crystallinity, surface hydroxyl density and oxygen vacancies [14].
The the co-doped photocatalyst (N-C-TiO2) has been proven as an effective photocatalyst with 91.3% degradation efficiency in 3 hours of irradiation time, in consequence of the presence of anatase phase and the fine-structure morphology of the photocatalyst.
Kale: submitted to Journal of Physical Chemistry (2008) [9] W.