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Yang 3, *f 1 School of Stomotology, Peking University, 100081, Beijing, PR China, 2 School of Stomotology, Jiamusi University, 154002, Heilongjiang, PR China, 3 The Key Laboratory of Beijing City on Preparation and Processing of Novel Polymer, Beijing University of Chemistry and Technology, Beijing, china, 100029 a dengxuliang@vip.sina.com, banniemmx@yahoo.com.cn, clidan721225@163.com, e suig2004@yahoo.com.cn, fkqhuxy@126.com, d yangxp@mail.buct.edu.cn.
The structure, morphology, molecular weight change of the scaffolds were investigated using scanning electron microscopy (SEM).
The structure, morphology and molecular weight change of the hybrid scaffolds were investigated and compared with those of PLLA /HA scaffolds.
The morphological structure of electrospun PLLA/HA fibers obtained from the 6% and 8% polymer solution under different voltages are shown in figure 2.
These structures were suspected to be the focal contacts or focal adhesions, which are structurally defined adhesion sites between the cultured cells and the ECM [12].

Bertran b State University of Campinas, Chemistry Institute, P.O.Box-6154, Campinas/SP, Brasil, 13083862.
The micrographs reveal that all the mineral phases of bone are composed of globular structures with sizes ranging between 70 and 90 nm.
In spite of the reduced resolution, the micrographs also indicate that the globular structures are formed from agglomerates of smaller particles with poorly defined shape and size around 20 nm.
The formation of bone mineral structures about 80 nm in size or bigger has been associated with the calcification of spaces existing between collagen chains throughout bone formation [2-5, 10, 11], but only rarely has their formation been reported as agglomerates of small particles [3, 4].
The Scanning Electron Microscopy and Debye-Scherrer results are in good agreement and permit proposing that the calcification process that results in the formation of structures around 80 nm in size is a consequence of the agglomeration of single fundamental morphological units around 20 nm in size.

Tsubakino 1 1 Department of Materials Science and Chemistry, Graduate School of Engineering, 2 Graduate Student, 3Graduate Student Himeji Institute of Technology, 2167 Shosha, Himeji, Hyogo 671-201, Japan Keywords: Magnesium alloy, AZ31, grain refinement, precipitates, hot-rolling, recrystallization.
Cold rolling in this case was about 30 % in reduction, which was possible because of a body centered cubic structure of the alloys in Mg-Li system.
In the present study, heavy hot rolling and annealing process has been applied to AZ31 magnesium alloys in order to obtain fine grained structures.
On the other hand, precipitates accompanied with strain field were observed in the AZ31(Mn) alloy annealed at 673 K as shown in Fig. 5 (d), which lead to the fine grained structure in Fig. 4 (d).
Precipitates formed in the alloys suppress grain growth, especially those in the AZ31 alloy containing manganese seem to have a higher redissolution temperature and lead to fine grained structure.

Introduction Biominerals, like bone, tooth and nacre, have exquisite structure and excellent mechanical properties in a confined reaction at room temperature [1-3].
A prime example is nacre, which consists of 95 % layered calcium carbonate (aragonite) with just 5 % percent of organic matrix for “brick-and-mortar” structure[4].
The structure of nacre imparts a high strength on the composite, of up to 3000 times that of aragonite alone, due to the release of tension through the elastic organic matrix.
Especially, part of the PSP began to carbonization, resulting in the collapse of dense structure at 400 °C (Fig. 4d).
Biomineralization Principles and Concepts in Bioinorganic Materials Chemistry; Oxford University Press: New York, 2001

Such a structure and chemical property makes it attractive when used as additives in commercial FCC operation [3,4].
As a newly developed technique, molecular simulation has been widely used in chemistry, chemical engineering, materials science, biology.
In the field of adsorption equilibrium between zeolites and adsorbates, Grand Canonical Monte Carlo method recently have been studied in zeolite skeleton and surface structure, the interaction between template and zeolite, adsorption and diffusion of adsorbates [5,6].
We selected the siliceous, cation-free analogue of ZSM-5 as the structure of adsorption with an unit cell composition of Si96O192 in the Puma orthogonal space group with a =2.0022nm, b = 1.9899nm and c = 1.3383nm.
The structure of ZSM-5 consists of two pores; straight channels with pore size of 0.53nm × 0.56nm and cross-linked sinusoidal channels of 0.51 × 0.56nm.

Introduction Perovskite structure transition metal oxide, potassium niobate (KNbO3), with inspiring ferroelectric, photoelectric, and catalytic properties [1], has been investigated widely as catalysis, optical wave-guides, and high capacity nonvolatile memory components [2,3].
The crystal structure and particle size were analyzed by X-ray diffraction (XRD) using the Bruker D8 Advance powder diffractometer with Cu Kα-radiation.
When sintered at 600 ℃, the characteristic peaks of KNbO3 phase appear and all of the indexed diffraction peaks of the sample are in good agreement with that of standard orthorhombic structure of KNbO3 (JCPDS file 32-0822).
Single-phase perovskite structure KNbO3:Pr is formed by direct crystallization from amorphous materials at 600 ℃.
[4] Te-Hua Fang, Yu-Jen Hsiao, Yee-Shin Chang and Yen-Hwei Chang, Materials Chemistry and Physics, Vol.100 (2006), p. 418

Introduction In recent years Bi2M4O9(M = Al3+,Ga3+,Fe3+) compounds with mullite-type structures[1], and their derivatives doped with M2+ ions (Sr2+,Ca2+,Ba2+) have received intense interest as they exhibit interesting properties, such as, mixed ionic electronic conductors (MIEC) and oxygen ionic conductivity.
Recent studies on solid solution series of mullite-type Bi2M4O9(M = Al3+,Ga3+,Fe3+) compounds, such as Bi2(M1-x(i)Mx(ii))4O9[6] and (Bi1-xSrx)2M4O9-x[7], which were synthesized in order to tailor the physical properties of Bi2M4O9 phases have considerably extended the mullite crystal chemistry.
All diffraction peaks can be indexed to the orthorhombic structure (space group = Pbam) of Bi2Ga4O9.
The microscopic structures for all samples are well.
Schneider, The Mullite-Type Family of Crystal Structures, ed.

Removal of Methyl Red from aqueous solution by adsorption onto Mg-Al HTlc Yunbo Zang College of Chemistry and chemical engineering, Shangqiu Normal University, 476000,China zangyunbo112@163.com Keywords: Sorption, hydrotalcite-like compounds, Methyl Red Abstract.
The metal hydroxide layers have structures similar to that of brucite, Mg(OH)2, in which divalent cations are octahedrally surrounded by hydroxyl groups, with the resulting octahedra sharing edges to form infinite sheets.
The chemical structure of MR is shown in Fig. 1.
Structure of MR Characterization of HTlc and sorption products Powder X-ray diffraction (PXRD) patterns were recorded with D/MAX 2200 PC diffractometer (Rigaku Industrial Corporation) with Cu-Kα radiation, 40 kV, 100 mA.
It can be seen from Fig.2 that the MR sorption did not changed the layered crystal structure and the basal spacing (d003) of the HTlc, indicating that the MR did not intercalate the gallery of HTlc.

Finite element analysis of the pasta frame structure was made in SCAD (Structure CAD) and ANSYS.
The internal force factors arose in the structure were compared.
Because of these mistakes the structure did not work as a single rigid system.
The bridge structure was designed and optimized in SCAD and ANSYS.
Mechanical properties of polymer composites reinforced with knit fabrics made of high-strength aramid fibres (2009) Fibre Chemistry, Springer, pp. 53–55

The environmental friendliness of materials prepared from renewable resources chiefly arises from the fact that materials engineers work in line with the synthetic abilities of flora by only somewhat amending the triglyceride, and still retaining the chemical natural structure [7], this was corroborated by [1] in a research on potential of thevetia peruvianan oil and reported that the oil contains triglyceride structure, with 3.16 carbon – carbon double bonds per triglyceride which can be used as starting material for bio-polymer production.
Schäfer (2011): Oils and Fats as Renewable Raw Materials in Chemistry.
Macromolecular Chemistry and Physics, 213, 87-96
Oriental Journal of Chemistry. 31, 2, pp 1169-1173
Larock (2005): Novel Thermosets Prepared by Cationic Copolymerization of Various Vegetable Oils – Synthesis and their Structure – Property Relationship.