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Odovi 4 1Faculty of Physical Chemistry, Belgrade, Serbia and Montenegro 2Faculty of Chemistry, Belgrade, Serbia and Montenegro 3 Institute of General and Physical Chemistry, Belgrade, Serbia and Montenegro 4Institute of Chemistry, Technology and Metallurgy - Department for Catalysis and Chemical Engineering, Belgrade, Serbia and Montenegro Keywords: 12-Tungstophosphoric Acid (WPA), Dehydration Process, Heteropoly Compounds, Hydration Degree ABSTRACT Heteropoly compounds can form several different crystallohydrates, but their stability depends on the ambient temperature and relative humidity.
They are widely used as good and selective catalysts, reagents in analytical chemistry, and due to good proton conductivity they can be used in different electrochemical devices, etc.
Other chemical and physical characteristics, such as polarizability, solvation number, ionic charge, etc., affect the structure significantly, especially the secondary structure of heteropoly compounds.
It has been concluded that the secondary structure of the Keggin ions depends on cations.
SpasojeviK - de Biré, Structure properties and proton conductivity of magnesium salt of 12-tungstophosphoric acid, Solid State Ionics 162- 163 (2003) 217-223

Introduction During the past decades, alkyldithio radicals (CnH2n+1SS) have generated people’s concern because of their potential significance in atmospheric chemistry, combustion chemistry, and environmental chemistry, and there have been some studies on their structures, energies, spectroscopies, and so on. [1-11] The methyldithio radical plays an important role in the formation of the acid rain, photochemical smog, and atmospheric ozonosphere destruction.
With this motivation, we have carried out a detailed study of structures, thermochemistry, and electron affinities of the above radicals and their anions using density functional theory (DFT).
All the electron affinities and radicals’ structures have been determined using the Gaussian 98 program suite.
Phys.53, 2823. (1970) [14]Huzinaga, S.; Approximate Atomic Wavefunctions II, Department of Chemistry, University of Alberta: Edmonton, Alberta, Canada, Vol.
J.; Modern Theoretical Chemistry; Schaefer, H.

MnO powder as anode material for lithium ion battery Mingsen Zheng*, Jun Zang, Quanfeng Dong State Key Lab of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, 361005, Xiamen,China mszheng@xmu.edu.cn; qfdong@xmu.edu.cn Keywords: MnO；Anode material; Lithium ion battery Abstract.
The morphology and structure character of MnO powder was studied by Field-emission scanning electron microscopy (SEM) and X-ray Diffraction.
The crystal structure of the products was characterized by X-ray powder diffraction (Philips Panalytical X-pert, using Cu Kα1 radiation λ=1.5405 Å).

In Fig. 1, a simplified crystal structure of Bi4Ti3O12 is shown [5].
The synthesis route has a strong influence on the structure and properties of BIT.
Fig. 1 Idealized structure of Bi4Ti3O12 showing bismuth oxide layers and pseudo perovskite units.
Mechanical activation has been successful with Pb-based electroceramics with perovskite structure [20].
Varela: Materials Chemistry and Physics (2005) (article in press)

Journal of Molecular Structure: THEOCHEM, 635(2003) 229-237
Journal of Molecular Structure: THEOCHEM, 578(2002) 79-88
Inorganic Chemistry, 27(1988) 734-740
The Journal of Physical Chemistry A, 110(2006) 1084-1093
Organic & Biomolecular Chemistry, 9(2011) 7168-7175

Introduction Atom transfer radical polymerization (ATRP) is among the most rapidly developing areas of synthetic polymer chemistry.
It combines chemistry with physics and processing/engineering to provide tools for rationally designing and preparing targeted functional materials.
Their structures were characterized by infrared spectroscopy and nuclear magnetic resonance.
X-ray diffraction studies were carried out to obtain more detailed information on the mesophase structure.
Nematic structure of polymer was confirmed with POM and XRD.

Influence of manganese and tin substitution on the structure and magnetic properties of CdCr2Se4 Izabela Jendrzejewska 1* , Paweł Zajdel 2, Jerzy Mroziński3, Ewa Maciążek1 ,Tomasz Goryczka 4 , Aneta Hanc4 , Andrzej Kita 1 1 University of Silesia, Institute of Chemistry, Katowice, Poland 2 University of Silesia, Institute of Physics, Katowice, Poland 3 Wrocław University, Faculty of Chemistry, Wrocław, Poland 4 University of Silesia, Institute of Materials Science, Katowice, Poland * izajen@wp.pl, pzajdel@us.edu.pl Keywords: crystal structure of spinel, X-ray-diffraction, Ritveld refinement, magnetic properties Abstract Single phase materials with general formula CdxMeyCr2Se4 (where Me = Mn, Sn) were obtained using solid state synthesis method.
Introduction CdCr2Se4 is a spinel with the AB2X4 structure, in which the Se-anions form a cubic close-packed lattice, with the Cd-cations occupying the tetrahedral sites and the Cr-cations occupying the trigonal antiprismatic sites.
Both samples were examined using powder X-ray diffraction method in order to make phase analysis and to determinate crystal structures and lattice parameters.

Where: C1 and C2 - stages of heating raw materials and hydrogen; В1 - reactions on the catalyst surface; A1 - hydrogenates of normal structure; A2 - hydrogenates of cyclic structure; A3-split hydrogenates.
This scheme consists of: 1 - lines of raw materials (deasphalted); 2 - hydrogen; 3 - heated deasphalted material; 4 - heated hydrogen; 5 - normal structure hydrogenizate; 6 - hydrogenate of cyclic structure; 7 - split hydrogenate; 8-normal hydrogenate; 9-isomerized hydrogenate; 10- split hydrogenate.
M.: "Chemistry", 1982
M.: "Chemistry", 1974
M.: "Chemistry" 1971

Chitosan chemistry and pharmaceutical perspectives.
Food Chemistry, 114, 1173−1182
Food Chemistry, 104, 21–29
Journal of Organic Chemistry, 69, 2309–2314
Bioorganic & Medicinal Chemistry, 15, 3775–3782.

In this case, alumino-phenylsiloxane polymer is used as matrix and provides control of the porous structure of the sorbent in the moment of its synthesis.
Avramenko, Uranium sorption on reduced porous iron oxides, Doklady Physical Chemistry, Issue 1, 1 May 2016 67-71
Avramenko, Wollastonite ceramics with bimodal porous structures prepared by sol - gel and SPS techniques, RSC Adv. 6 2016 34066–34073
Avramenko, Synthesis of hydrophobic oil sorbent based on silane-siloxane microemulsion, Proc. dokaldov XX Mendeleev Congress on General and Applied Chemistry, Volume 4 2016 59
[4] Yicheng Zhang, Kake Zhu, Xinggui Zhou and Weikang Yuan, Synthesis of hierarchically porous ZSM-5 zeolites by steam-assisted crystallization of dry gels silanized with short-chain organosilanes, New journal chemistry 38 (2014) 5808–5816