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Catalytic cracking of n-hexane over MeAPOs molecular sieves Lili Feng1,a, Chongchen Wang1,b, Xingyi Qi2,c 1Key Laboratory of Urban Stormwater System and Water Environment (Beijing University of Civil Engineering and Architecture), Ministry of Education, Beijing, 100044, China 2School of Chemistry and Environment, Beihang University, Beijing, 100191, China afenglili@bucea.edu.cn, bwangchongchen@bucea.edu.cn, cqixy@buaa.edu.cn Keywords: MeAPO-5, MeAPO-11, n-Hexane, Catalytic cracking Abstract.
Introduction Aluminophosphate molecular sieves (AlPO4-n) with a variety of structures have attracted intensive attention since 1982 for the increasing demands on the catalysts in specific reaction processes[1].
It is now well established that catalytic cracking reactions are promoted by Brønsted acid sites, and that the activity and product distribution mainly depend on Brønsted acid strength and concentration as well as microporous structures of these materials [7–9].
They show the same structure as their parent AlPO4-5 (AFI type) or AlPO4-11 (AEL type).

Different crystalline phase will affect its properties in charge and electronic structure [6].
The surface structure, morphology and optical properties of TiO2 nanorods were also investigated.
All reagents used in this study were of analytical grade and used without further purifications and were purchased from Sigma-Aldrich Chemistry.
Using FESEM we were able to capture the structure of the TiO2 nanorods at high magnification.

Influences of Current Density on Tribological Characteristics of Ceramic Coatings on 6061 Al Alloy by Plasma Electrolytic Oxidation Xiaodong Wang1, a, Xiaohong Wu2,b, Rui Wang3,c and Songtao Lu4,d 1Department of Chemistry, Harbin Institute of Technology, Harbin, Heilongjiang, 150001, China awangxiaodong_528@163.com, bwuxiaohong@hit.edu.cn, cwangrui001@hit.edu.cn, dlusongtao@hit.edu.cn Keywords: Plasma electrolytic oxidation, Ceramic coatings, 6061 Al alloy, Tribological characteristic.
In this study, influences of current density on the structure, morphology and tribological characteristics of ceramic coatings on 6061 Al-Mg alloy by PEO are researched[8,9].
That may because the ceramic coating has the porous structure and the X-ray can easily penetrate into the coating to the substrate.
The results showed that the current density influences on the structure, morphology, friction coefficients and wear resistance of the ceramic coatings by PEO.

The morphologies and crystal structure of the mineral powder were observed and determined by scanning electron microscopy (SEM) and X-ray diffraction (XRD).
The morphologies and crystal structure of the mineral powders were observed and determined by scanning electron microscopy (SEM) and X-ray diffraction (XRD).
It can be seen that the powders have lamella structure with irregular section, and the average size is about 0.8µm.
Fig.1.b gives the XRD spectrum of the mineral powders, of which the main ingredient is serpentine, and the crystal formulation chemistry is Mg3(Si2O5)(OH)4.

Summary A high-temperature, fresh-dispense SPM-only process is reported and evaluated for the 45nm CMOS NiPt salicide process with SiGe structures.
This SPM-only selective metal etching process is also proven to be compatible with PMOS strained SiGe structures.
[7] Cotton, Simon A., Chemistry of Precious Metals, Springer-Verlag, 1997
Baseline(HCl based) - - - - - OK NG SPM only - T2 - - NG OK OK - SPM only - T3 NG OK OK OK - - NG: Pt residue or salicide damage; OK: No Pt residue and damage free Figure 4: Sheet resistance comparison between SPM-only T2 and SPM-only T3 at N+/P+ AA and Poly areas a b a b Figure 5: a) PMOS with SiGe structure; b) No salicide attack and Pt residue found for SPM-only T2 at SiGe areas.

Taïbi-Benziada 2 1 Department of Chemistry , A.
Among these materials, strontium titanate (SrTiO3) is a well known paraelectric perovskite structured material, having a cubic symmetry at room temperature ( space group Pm3m, lattice parameter ac = 3.904 Å ) [1].
Superlattice reflections are detected with the formation of a complex perovskite structure isomorphous with NaNbO3.
The TiO6 and MgF6 octahedra in the perovskite structure have almost the same size.The increase in cation size in going from Ti4+ to Mg 2+ is compensated by the decrease in the anion size from O 2 to F - (rTi4+ = 0.605 Å; rMg 2+ = 0.72 Å ; rO 2 = 1.40 Å ; rF = 1.33 Å) in hexacoordination.

The crystal structure of the BTHA was not changed before and after NaOH treatment.
The crystal structures of the BTHA powder were not changed before and after calcination (Fig. 3(a)), but the XRD signatures exhibited a substantial increase in peak height and a decrease in peak width, thus Fig. 1 (a) XRD pattern and (b) FTIR spectrum of BTHA powder before NaOH treatment.
Elliott: Structure and Chemistry of the Apatites and Other Calcium Orthophosphates (Elsevier 1994)

The –OH in its’ end structure could combined with H+ to remove down and the remained conformed C+.
All the PAHs content decreased more or less, especially .Benzo[b+k]fluoranthene, Benzo[e]pyrene and BaP which the amount of ring were more than 5 and structure was more asymmetric. 3.2 coal tar pitch + Epoxy Resin From the figure 8 to 12, it can be seen that Epoxy Resin could also decrease the carcinogenic of the coal tar pitch effectively.
It can be seen that the content of the SP, Penetration, TI and βresin increased greatly compared with untreated pitch..This result could be explained by that the modifiers showed high reaction activity with PAHs and the structure of the product became high molecularity.
Hoke, Ullmann’s Encyclopedia of Industrial Chemistry, vol.

The target metal selected is copper ions for the feasibility examination of conductive metal line fabrication Introduction Recent advances in supramolecular chemistry have made possible the fabrication of a variety of nanoscopic entities such as metal and semiconductor quantum particles, organized mono- and multi- layers of organic molecules, and various hybrid assemblies containing both organic and inorganic components [1].
The height or thickness of copper island was controlled by the repeated adsorption and reduction process, which consisted of additional adsorption and reduction process and improved the coverage and thickness of copper structure.
For such applications, the ability to assemble complex functional structures with precisely defined nanoscale dimensions is critical.
Spatially defined metal structure on organic monolayer templates can be manufactured by precise control of experimental conditions, such as the composition of monolayer template and target metal ion.

The oxidized ND (OxND) was then introduced into a pre-polymer matrix to form linear assemblies of OxND (LAOxNDs) structures via the field-induced organization of OxND particles under effect of electric fields: AC, DC or switching DC.
The enlarged aggregates of OxND started to relocate and assemble together to minimize the electrostatic energy [1], thus structure some LAOxNDs parallel to the electric flux.
Because the conducting channels of amorphous carbon were structured concurrently with the formation of linear assemblies of ND (LANDs) in the matrix, the resistivity of ND hybrids gradually decreases after AC, DC and switching DC electric field applications (Fig. 5).
Gogotsi, Control of sp2/sp3 carbon ratio and surface chemistry of nanodiamond powders by selective oxidation in air, J.