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Increasingly, there is recognition that a full characterization of alloy microstructure involves not only the conventional parameters such as grain size, texture, inclusions, the more nanoscale microstructural elements such as defect structures, the structure and chemistry of fine scale precipitation, but also of the atomistic level structures such as solute-solute distributions, including vacancies and atomic co-clustering.
We consider this as extrinsic cluster-assisted nucleation, because the solute species of the initial co-cluster are not strictly constituents of the crystal chemistry of � (Al2Cu).
Summary of Clustering and Precipitation Processes in Al Alloys Precipitate & Structure Example Alloy (at. %) Observed Clustering & Precipitation Processes Selected References �': Al2Cu bct, I4/mcm, a=0.404 nm c=0.580 nm {001}�//{001}�' {010}�//<010>�' Al-1.7Cu0.01Sn Sn clusters independently from Cu forming Sn particles.
In this way, researchers can view a tomographic reconstruction of materials, since 3D images of the internal structure are generated by the reconstruction along z of thousands of 2D x-y slices.
In addition, the distribution of cluster chemistry and cluster morphology can be determined.

Fortunately, the reactive functional groups such as carboxyl, hydroxyl and amine in the structure provide the opportunity to modify these materials using carbodiimide chemistry[5].
(a) (b) (c) (d) Figure 2 (a) The distribution of hepatocytes on chitosan/PLGA film after 12d culture observed by optical microscopy; (b) The morphology of hepatocytes on collagen/chitoan film (SEM) crosslinked by EDC; (c) and (d) the morphology of hepatocytes on collagen/PLGA film (SEM). 0 20 40 60 80 100 120 140 0 5 10 15 20 Time (d) Albumin Concentration ug/ml Figure 3 The albumin secretion of hepatocytes on collagen/PLGA film. 3.2 Scaffold prototyping As aforementioned, to combine the good biocompatibility of collagen as well as excellent mechanical properties of PLGA, the scaffolds mimicking 3-D structure as natural hepatic tissue, namely, the spindle porous scaffold with multi-channels and multi-layers for transportation of 70µm nutrient and plasma, and the one made by dewaxen-casting method are primarily developed as shown in Fig. 4(a) and (b).
Two types of scaffolds composed of collagen and PLGA with novel structures hold the promising to be used in liver tissue engineering.

Barnes, Structure and Performance of Cements, Taylor & Francis, London, 2002
Hornsby, Multifunctional Barriers for Flexible Structure, Springer, Berlin, 2007
Lu, Molecular dynamics simulations on the interfacial structures of electrolyte solutions, Acta Chimica Sinica. 67 (2009) 12-16
[6] Z.X.Yan, Complex Chemistry, People Educational Press, Beijing, 1960.

For a long time many experts and scholars have researched on rocks and minerals, chemistry, sedimentary environment, provenance, mineralization age, and mass balance calculation of the bauxite [1-15].Though there are abundant outcomes of WZD bauxite, analysis on oxidized and reduced conditions in penecontemporaneous period of the bauxite is poor.
For WZD bauxite not only color but also structure are controlled by component, and structure of high grade bauxite is loose than low grade bauxite.
Color and structure are bound with grade demonstrates that in penecontemporaneous period metallogenetic environment is oxidized because just in oxidized conditions Fe in bauxite can be removed.

Table 1 Raw materials chemistry composition % Raw material TFe FeO CaO SiO2 P Iron ore 46.48 5.6 8.75 8.22 0.98 Lime — — 75.6 2.46 — Table 2 Coal powder industry analysis % FCad Vdaf Ad Mad 79.44 8.44 12.05 1.28 Experiment results According to the temperature and basicity in the high-phosphorus hematite carbothermal reduction process, the experiment methods were designed and the KAH-1 microwave furnace was used, the experiment results were showed in Table 3.
Fig. 2 Basicity influence on dephosphorization and iron yield rate Microstructure analysis The product SEM of the high-phosphorus hematite carbothermal reduction in the microwave field was in Fig.3.The oolitic structure was cohered and blended to each other, meantime a lot of iron metal was formed.
(a) XC/XO=1, 950˚C, R=1.6 (b) XC/XO=1, 1050˚C, R=1.2 Fig. 3 Sample SEM picture after reduction Conclusions The primary high-phosphorus hematite structure was changed by high-phosphorus hematite carbothermal reduction in microwave field.
The inset structure of apatite was destroyed by the iron particle gathered and grown up,which was good for the separating of the reduction iron and the high-phosphorus slag.

Kinetic studies on the polymerization of dicyclohexylmethylmethane -4,4'-diisocyanate with polyoxytetramethylene diol Jian Cheng WANG School of Chemistry and Pharmaceutical Engineering, Shandong Polytechnic University, Jinan 250353, P.R.China yyhasdf1897@sina.com Keywords: Dicyclohexylmethylmethane-4,4'-diisocyanate; Polyoxytetramethylene diol; Kinetics; In situ FT-IR Abstract.
The structures of raw materials, i.e., isocyanates or alcohols, are an important factor to affect the urethane reaction kinetics.
For example, Yilgor et al. [5] reported that the symmetry of isocyanate greatly impacts the thermal behavior and weaving structure of materials.
Except for the structures of raw materials, solvents also play an important role during the polyurethane synthesis.

Introduction Directly controlled by the computer without D/A converter, with the advantages of simple structure, low cost and high reliability and so on, the digital control of pneumatic valve has gained more and more popularity and become the focus of recent research.
The working principle of the valve The working principle diagram of the dual piezoelectric-driving pneumatic digital valve is shown in Fig.1 and its overall structure diagram is shown in Fig.2.
Fig.1 The valve working principle diagram Fig.2 The valve overall structure diagram Control method simulation research of the valve The Valve Combined Simulation Model The valve combined simulation model is built based on the AMESim and Matlab/simulink joint simulation platform as shown in Fig.3.
Materials Chemistry and Physics, 2006, 97(1): 1~4

The oxidation of the petroleum resin allows inclusion into the structure of the molecule of up to 13 % of epoxide groups, which later on will intensify the process of the composition condensation by macromolecular crosslinking [3, 5].
This is due to overheating of the coating and the destruction of the molecular structure - breaking intramolecular bonds.
The structure of the coating surfaces are illustrated in figures 3 and 4.
Chemistry and chemical technology 4 (2010) 325-329

Catalysis Investigation of PET Depolymerization by Superacid SO42- /γ-Al2O3 under Microwave Irradiation* Yongshuai Ma1,a , Qinghua Tang1, b and Dong Zhang1,c** 1Institute of Applied Chemistry, Wenzhou University, Wenzhou, zhejiang, 325035, China ama1064@126.com, bspring_loveqinhua@126.com, cdzhang@wzu.edu.cn Keywords: SO42- /γ-Al2O3 superacid ; microwave irradiation; PET; hydrolysis Abstract.
It was well known that the acid center could be formed well by controlling a calcination temperature for catalysts, and the amorphous structure of catalyst would be effective for the formation of acid centers[5].
It was obvious that the structure of superacid SO42- /γ-Al2O3 was amorphous.
Moreover, the sulphur of catalysts surface would run off and superacid structure would be damaged at high calcination temperature [5], so the catalysts calcined at 750°C was also not effective to catalysis.

Synthesis and Properties of a Novel Diarylethene Having Two Fluorines Gang Liu, Ming Liu, Shouzhi Pu* Jiangxi Key Laboratory of Organic Chemistry, Jiangxi Science and Technology Normal University Nanchang 330013, P.
The photochromic process of diarylethenes is based on a reversible transformation between the open-ring isomer with a hexatriene structure and the closed-ring isomer with a cyclohexadiene structure, according to the Woodward-Hoffmann rule [5].
The structure of compound 1o was confirmed by melting point, 1H NMR and 13C NMR spectroscopy: Melting point 140.9~142.1 °C; Anal.