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Because simulation can optimize internal structure and reduce cost, several groups made meaningful simulations [1-9].
Schematic structure of HVPE reactor for GaN growth Table 1 The initialization of the boundary condition The flow is considered steady flow and incompressible fluid model is adopted in the simulation.
Karpov, et al., “Surface chemistry and transport effects in GaN hydride vapor phase epitaxy,” Journal of Crystal Growth, vol. 270, Sep. 2004, pp. 384-395, doi:10.1016/j.jcrysgro.2004.0 7.018

The previous studies both at home and abroad are mainly focused on the properties of ceramic honeycomb, and some are related to the properties of the whole ceramic oxidation bed[2-3], but researches about the inner structure of the oxidation bed is still a blank.本文采用数值模拟方法研究陶瓷氧化床的阻力性能，就是为工业应用提供设计依据。
In accordance with the structure characteristics of the ceramic honeycomb: square-hole ceramic honeycomb has a large specific surface area, hex-hole ceramic honeycomb has good flow properties.
[In Chinese] [5] M.LUO, J.F.LIU, T.ZH.DU: Computers and Applied Chemistry.

Curing, Thermal Properties and Flame Resistance of Tetrabromo-BPA Epoxy Resin/ Boron-Containing Phenol Resin Jungang Gao*a, Xuefang Zhangb, Hongqiu Lvc College of Chemistry and Environmental Science , Hebei University, Baoding 071002 , China agaojg@hbu.edu.cn,byanzhaxuefang@yahoo.com.cn,clvhongqiu08@163.com Keywords: bromo-epoxy resin, boron-containing phenol resin, thermal properties, fire resistance.
However, the phenolic hydroxyl, ether bond and methylene in the structure of phenolic resin are easily oxidized.
On one hand, the B-O bonds can form to three-dimensoonal structure and increase the cross-linked density of curing system and may form six-membered rings [6], these will hinders thermal motion of the molecular segmer, so the glass transition temperature (Tg) will increase.

Therefore the surface structure became more stable and the oxidation temperature improved with boron concentration rising.
Crystal structure distortion and more defects due to high boron doping in GICs supply more nucleation sites for diamond growth.
These characteristics may be used to investigate the redox kinetics in the electroanaltycal chemistry. 1000 1200 1400 1600 1800 2000 0.010 0.015 0.020 0.025 0.030 0.035 1332cm-1 Raman Intensity Raman Shift cm-1 �� � Fig.1 Raman spectrum of B-doped diamond Fig.2 SEM images of B-doped diamond -1.0 -0.5 0.0 0.5 1.0 -10 -8 -6 -4 -2 0 2 4 6 8 10 Current/10 -6 A Potential/V -0.5 0.0 0.5 1.0 1.5 -30 -20 -10 0 10 20 Current/10 -6 A Potential/V � ����������������� (a) (b) -0.5 0.0 0.5 1.0 1.5 2.0 -20 -15 -10 -5 0 5 10 15 20 Current/10 -6 A Potential/V 0.0 0.5 -5 0 5 Current/10 -6 A Potential/V � (c) (d) Fig.3 Cyclic voltammograms of B-doped diamond powder electrode in different electrolytes of (a) 0.1M KCl, (b) 0.5M Na2SO4, (c) 0.1 M H2SO4, (d) 0. 5M Na2SO4 containing K3Fe(CN)6 and K4Fe(CN)6 (each 20mM), scan rate 0.2V/s Raman shift [ -

Mechanical Properties and Morphologies of Rice Husk Silica/Epoxy Nanocomposites Xueqing LiuPaP， Jiyan LiuPbP College of Chemistry and Environmental Engineering, Jianghan University, Wuhan 430056, China PaPE-mail: liuxueqing2000@163.com ; Pb PE-mail:HTUliujiyan918@163.comUTH Keywords: nanocomposites; silica; mechanical properties; morphology; thermosets Abstract: Amorphous rice husk silica with purity of 99.3% and the specific surface area value of 212 mP2P/g was obtained by burning the dilute HCl treated rice husk at 600℃.
Introduction Epoxy resins are widely used in various engineering and structure applications such as electrical industries, commercial and military aircrafts industries.
The formation, physical properties and structure of nano silica from rice husk depend on the experimental condition [5-7].

Introduction Carbon nanotubes (CNTs) have emerged as a miracle material that will have significant impact on the 21st century due to their unique structure.
In both cases, the final functionality of the nanotube surface should, in principle, match the chemistry of the matrix [10].
This convenient noncovalent method can be employed to graft other functional polymer chains onto MWCNTs, and may be useful for the preparation of MWCNT- polymer hybrid nanomaterials without risking the destruction of the intrinsic graphitic structure of the pristine MWCNTs.

He et al. [2] investigated the effects of the particle size, fuel chemistry and the fuel–oxygen ratio on: (1) the particle temperature while impinging on the substrate; (2) the volume fraction of W2C phase and; (3) the porosity in the coatings.
Typical lamination structure in thermal spray coating exists in 2# coating.
Table 4 Mechanical properties of conventional and nanostructured coatings coating number micro-hardness(GPa) Young’s Modules(GPa) fracture toughness(MPa·m1/2) 1 12.37 293.4 4.59 2 12.16 267.78 3.686 A lot of researches have been done on the indentation crack propagation and fracture toughness for traditional uniform structure of the carbide.

This method changed structure and component of the surface, produced more active sites and increased the quantity of polar functions.
Nevertheless, over-content fiber may influence the structure of foam cell and decrease toughness.
Chemistry and application of phenolic resins.New York: Springer; 1979

In the case of forenamed composites, a better electromagnetic match is obtained due to its specific structure in which the Fe3Al and Fe is surrounded by Al2O3.
The good absorption properties may be ascribed to the proper combination of the complex permittivity and permeability which is tuned by the special structure and the strong nature resonance.
Machida: Chemistry Letters, 32 (2003) 394-395

Kilmartin1,a 1Hybrid Polymers Research Group/ Polymer Electronics Research Centre, Department of Chemistry, University of Auckland, Private Bag 92019, Auckland, New Zealand ap.kilmartin@auckland.ac.nz Keywords: polyaniline, conductivity, radical scavenging, degradation, amorphous Abstract.
A three-dimensional chemical structure, resulting from crosslinking, is known to decrease the crystallinity and apparently increase the amorphous state of polyaniline [10].
The decline in the free radical capacity could be presumably attributed to the changes in the chemical structures of the polyaniline due to crosslinking and degradation evidenced by XRD and TGA results.