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The contemporary elaborations of the endo-prosthesis structure are directed to exchange of chirulen by ceramic material that leads to the change of the endo-prosthesis structure, development of new ceramic materials with the improved physical and mechanical characteristics, development of processing of internal and external spherical surfaces, development of diamond tools providing the high quality of the machined surface, definition of the optimal wear resistance of the pair of materials for manufacture of the endo-prosthesis etc.
Together with indisputable positive qualities, the contemporary structures of endo-prostheses from metal, ceramics polymers have certain defects.
This problem was solved by means of formation of Nano - and composition structure in technically pure titanium.
Problems of mechanics and physico-chemistry of the process of abrasive machining, Kiev 2002, pp. 490-499

PCL and PEG also have good elastic recovery property [12] and is widely studied in tissue structure.
(a) G1 (b) G2 Figure 1 Structure sketches of specimens, (a) three layers mPEG-PCL-mPEG, denotes as G1.
The polymer film will form a layer by layer structure and easy to degrade in solution.
Janson (Ed.), High Performance Non-Oxide Ceramics II, Structure and Bonding, 102 (2002) 47
Sharma, Review Paper: Absorbable Polymeric Surgical Sutures: Chemistry, Production, Properties, Biodegradability, and Performance, J.

Introduction Biocalcification refers to the process of calcium carbonate precipitation by biological systems, and refers also to the final product, the calcified structure, whatever it is: a mollusc shell, a coral exoskeleton or a bacterial crust.
In the Metazoa, biocalcified structures are synthesized within an organic matrix produced by specific cells, tissues or syncitia.
For instance, previous works on the staghorn coral Acropora millepora [17] or on the calcareous sponge Sycon raphanus [11] have shown such a sequential expression of CA isoforms during the ontogeny of the corresponding calcified structures.
They correspond to the statocysts, geo-sensory structures that synthesize statoliths, tiny calcium carbonate concretions involved in the equilibration of larvae in the seawater during its development cycle [22].
To clarify the activity vs. the expression of CAs during the developmental stages of H. tuberculata and the specific expression pattern of CAs involved in biocalcification, further work needs to be developed, in order to fully understand the subtle chemistry of CA.

The aim of this work is to investigate by X-ray photoelectron spectroscopy (XPS) and Grazing incidence X-ray diffraction (GIXRD) the influence of the ion implantation on the chemistry and structure of the surface of the 430 steel, in order to explain its effect in the corrosion behaviour in a chlorinated medium.
Those results suggest that certain similarity exists between the passive layer formed on unimplanted and Cr + implanted steels while differentiated structures are formed in the remaining implanted surfaces.
The composition and structure of the passive layer naturally formed on the AISI 430 has been previously characterized [15].
According to the obtained spectra, the film structure is similar to that of the unimplanted steel, but with an increased Cr/Fe ratio in the external layers.

The Effect of Ni Precursor Salts on Diatomite Supported Ni-Mg Catalysts in Methanation of CO2 Chao Sun1,a, Jugoslav Krstic2,b, Vojkan Radonjic2,c, Miroslav Stankovic2,d*, Patrick Da Costa1,e* 1Sorbonne Universite, Institut Jean Le Rond D’Alembert, CNRS UMR 7190, Saint-Cyr-L’École 78210, France 2Universtiy of Belgrade, Institute of Chemistry, Technology and Metallurgy, Njegoseva12, 11000 Belgrade, Serbia achao.sun@dalembert.upmc.fr, bjkrstic@nanosys.ihtm.bg.ac.rs, cvradonjic@nanosys.ihtm.bg.ac.rs, *dmikastan@nanosys.ihtm.bg.ac.rs, *epatrick.da_costa@sorbonne-universite.fr Keywords: Diatomite support, Ni-Mg catalyst, Ni precursor salt, CO2 methanation.
It is proposed to design a Ni-based catalyst with special structures such as hydrotalcite and perovskite, which have a very high thermal stability against sintering [16].
In conclusion, NiMg/D-N sample possesses the highest SSA and good porous structure.
CO2 hydrogenation to methane over mesoporous Co/SiO2 catalysts: Effect of structure.
Effect of silver modification on structure and catalytic performance of Ni-Mg/diatomite catalysts for edible oil hydrogenation.

Their use allows to reduce the amount of clinker cement, to increase the density of the structure, strength, durability and stability of concrete in an aggressive environment.
In addition, the structure contains a small amount of β-quartz, chalcedony, clay impurities, represented by dolomite СаMg(СО3)2, magnesite MgСО3, siderite FeСО3 (Fig. 1) [12, 16].
Given that particles of fine chalk can form additional centers of crystallization, accordingly, there is a change in the quantitative ratio of structure-forming and destructive factors during the synthesis of strength of cement stone and concrete.
Electron microscopic studies of cement stone confirmed the presence of a dense structure of the samples (Fig. 5).
Advances in chemistry and chemical technology.

The crystal structure is a 7/2 helix, i.e. seven monomers repeat units with two turns in a period of 1.93 nm.
The broad XRD patterns indicate that the PEO structure transformed largely into amorphous phases by the non-equilibrium processing as well as the MWCNT addition.
It has been known that the spherulitic microstructure, typical for some polymer materials, which consists of crystalline lamella are the dark area, and the region between the spherulitic structures are bright area.
Such pores and cracks as well as visible sperulitic structures completely disappeared by ball-milling (Fig. 3b).
Gray: Polymer Electrolytes, The Royal Society of Chemistry, Letchworth, HN, 1997 [2] P.

Ten types of surfactants, including SDS (lauryl sodium sulfate), SL (sodium dodecylsulphonate), ABS (sodium dodecylbenzenesulfonate), Tween-80, Tween-60, Tween-40, Tween-20 were obtained from Aladdin Chemistry Co., Ltd (Shanghai); AOS (α-alkenyl sulfonate) was obtained from Xinri Chemical Co., Ltd (Taiwan); 20YB was obtained from Kao Chemical Co., Ltd.
Since surfactants had a characteristic amphipathic structure, in the foam system some of the surfactant molecules were expelled to the air/aqueous interface with their hydrophilic group in the aqueous phase and their hydrophobic group oriented away from it.
AESO was a type of anionic surfactant and there was abundant ether bonds in its structure so that it’s favor in hydrophilic ability.
In addition, for the difference ability of hydrophilic and oleophilic with closer molecular packing densities, they would construct a jagged stereoscopic interfacial structure [13-15].
In fig. 2 it showed that the surfactant system had significant implication with 20YB addition, which might result from each component competed for available space in the interfacial and formed special stereoscopic structure.

Novel thermally stable epoxy-polyurethane composites: preparation, characterization Jing Lin1, Qiuzhuan Yang1, Xiufang Wen1, Zhi-Qi Cai1, Pihui Pi1, Jiang Cheng1, Zhuoru Yang1, a 1School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510640, China aemail: zhryang@scut.edu.cn Keywords: Polyurethane, Novolac epoxy resins, Propionic acid, Thermal stability.
To overcome this limitation, many studies reported that introduction of thermally stable heterocyclic structures such as isocyanurate, oxazolidone, imide, triazine group into PUs backbone could greatly improve the thermal stability of PUs [15].
Finally, the chemical structures of MEP and cured epoxy-polyurethane composites were characterized by FTIR, 1HNMR analyses.
In addition, multiplets for protons of methylene (-CH2-) connected the phenoxy and the epoxy ring, methyl protons, protons of methylene (-CH2-) connected benzene ring and benzene ring, methane (-CH-) protons in the epoxy ring and aromatic protons on benzene ring of MEP in Fig.3 (c) were consistent with the proposed statistical structures of EP in Fig.3 (a).
And the structures of MEP were characterized by FTIR, 1HNMR analyses.

Heusler compound structure.
The calculated electronic structure of Na3Bi.
(a) Band structure of Mg3Bi2 without SOC.
(a) Crystal structure of full Heusler Co2TiX.
[8] Graf T, Felser C and Parkin S S P Simple rules for the understanding of Heusler compounds Progress in Solid State Chemistry 39 (2011) 1-50