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Introduction The control of grain structure represents a fundamental aspect in developing the desired mechanical properties and formability characteristics in aluminium alloys.
The Smith–Zener pinning effect of dispersoids has been shown to refine the grain structure after hot rolling significantly.
Mass transfer equations were solved in DICTRA using planar geometry with a 50 μm diffusion cell and an α-Al FCC matrix structure, representative of half the cell size for the case of grain-refined ingots.
The result was an equilibrated, more uniform composition profile across the grain interiors, representing a homogenized α-Al matrix chemistry suitable for subsequent precipitation modelling.
Both α-Al₁₅(Fe,Mn)₄Si₂ and β-Al₆(Fe,Mn) phases nucleated simultaneously; however, due to the alloy chemistry, particularly the presence of Si, the α-phase dispersoids dominated.

Studies on preparation and properties of SiO2/PVA-PAMPS composite Membrane CHEN Xiao-Xia1a, GUO Gui-Bao1b* 1 School of Chemistry and Chemistry Engineering, Inner Mongolia University of Science & Technology, Baotou 014010, China a nmgchenx @126.com, bggb66733@sohu.com *Prof., to whom correspondence should be addressed.
The use of methanol gives some advantages, compared to the hydrogen systems: the storage of fuel is easier and the systems can have a simpler structure[1].

The Solvent Influent on the Properties of TiO2: V4+ Nanoparticles Prepared by Hydrothermal Method Nguyen Minh Thuy1,a, Duong Quoc Van1, Le Thi Hong Hai2, Nguyen Manh Nghia1 and Nguyen Hong Quan1 1 Department of Physics, Hanoi National University of Education, Hanoi, Vietnam 2 Department of Chemistry, Hanoi National University of Education, Hanoi, Vietnam a thuynm@hnue.edu.vn, dqvansp@gmail.com Keywords: semiconductors, nanocrystals, photocatalysts, absorption, irradiation.
The structure and crystalline characters were analyzed by X- ray diffraction (XRD) SIEMENS D5005 and micro- Raman spectroscopy.
Li Li, Chun-yan Liu, Yun Liu, Materials Chemistry and Physics 113, pp.551– 557, (2009)

Introduction Coal pyrolysis relates to almost coal thermal conversions such as gasification, liquefaction and combustion, so the researcher of coal pyrolysis is very significant to coal chemistry.
During coal pyrolysis, numerous free radicals are formed by the cleavage of bridge bonds existed in the coal structure [5].
Elliott, Chemistry of Coal Utilization,1981 [8] A.

When the temperature is raised above 160℃, the gel structure is destroyed and it becomes a sticky fluid.
Oilfield Chemistry [M].
Gel chemistry.

Hassan 2, b and Zena Mohammed Ali Abbas3, c * 1,3 Iraq, University of Diyala, College of Science, Department of physics 2 Iraq, University of Diyala, College of Science, Department of Chemistry Email: atahseen_phy@yahoo.com, b drkarim1953@yahoo.com, c zenaalbana@yahoo.com Keywords : Zinc oxide, nanoparticles, X-ray diffraction, scanning electron microscope.
These structures are expected to have potential applications in building functional nanoelectronic devices.
XRD study is most important tool used in nano materials science and it is one of the primary techniques used by mineralogists and solid state chemists to examine the physico-chemical make-up of unknown materials and it is an important as characterization tools in solid state chemistry and materials science.

Bolt2,c 1 Department of Chemistry, 2 Centre for Advanced Composite Materials, The University of Auckland, New Zealand ajlu046@aucklanduni.ac.nz, baj.easteal@auckland.ac.nz, ccj.bolt@auckland.ac.nz Key words: Rheology, crosslinking, emulsion, vinyl acetate, glycidyl methacrylate, diamine Abstract: Isothermal kinetics studies of thermal-induced gelation for epoxy functionalized poly(vinyl acetate) emulsion and diamine were investigated rheologically.
The higher value of Ea for the present system ascribed was properly due to the very strong physical interaction between the emulsion particles which in turn leads to formation of a very strong network structure. 4 Conclusions The viscoelastic material functions changed at the onset of cross-linking with different degrees of sensitivity to the gel formation.
Macromolecular Chemistry and Physics, 1999. 200(9): p. 2048-2058. 5.

Combustion synthesis of hydroxyapatite and hydroxyapatite (silver) powders R.Narayanan1,a, Vijay Singh2,b, Tae-Yub Kwon1,c & Kyo-Han Kim 1,d 1 Department of Dental Biomaterials, School of Dentistry, Kyungpook National University, Daegu, Korea 2 Department of Chemistry, Kyungpook National University, Daegu, Korea a rnarayan69@hotmail.com b vijayjiin2006@yahoo.com c tykwon@knu.ac.kr d kyohan@mail.knu.ac.kr Keywords: combustion synthesis; hydroxyapatite; silver; XRD; chemical durability Abstract Hydroxyapatite powder is produced using combustion synthesis method.
A semiquantitative analysis shows CaO constitutes about 8% of the powder chemistry and the rest being made up of HA phase.
The nanodimensions of hydroxyapatite of HA powder are significant because nano-structured apatite increase osteoblast functions [7].

Introduction Much work has been done to increase the r-value by optimizing steel chemistry and processing conditions to improve drawability [1-5].
It is known that dynamic recovery easily occurs at higher temperatures during ferritic hot rolling, in which the steel has a bcc crystal structure.
Experimental procedure IF steels with two chemistries, i.e., 0.23% Ti-added and 0.16% Nb-added steels, were investigated in this study.

The quasi-steady magneto-plasma-dynamic (MPD) arcjet generator, as shown in Fig.1, is a promising plasma accelerator, which has a coaxial electrode structure similar to those of conventional plasma torches [1].
Symp. on Plasma Chemistry, Praha, Czech Republic, 1999, p.1977 [9] T.
Symp. on Plasma Chemistry, Orleans, France, 2001, p.2219 [10] H.