Search results

Influence of dipolar interactions in ferroelectric vinylidene fluoride copolymers on their structure and low-temperature molecular mobility KOCHERVINSKII V.V. 1,a, MALYSHKINA I.A.2,b, PAVLOV A.S.1,c, BESSONOVA N.P.1,a, KOZLOVA N.V.1,a, SHMAKOVA N.A.1,a 1Karpov Institute of Physical Chemistry, Vorontsovo Pole, Moscow, Russia 2M.V.
Lomonosov Moscow State University, Physics Dept., Leninskie Gory 119991 Moscow, Russia akochval@mail.ru, bmalysh@polly.phys.msu.ru, chonlog@mail.ru Keywords: ferroelectrics, molecular mobility, structure, relaxation transitions Abstract.
The role of the mentioned phase in mechanism of formation of domain structure is not well understood yet, so this problem is actual.
Investigations of molecular mobility in disordered phase of polymers under study can define more exactly the mechanism of formation of domain structure and its reaction on external electric field.
Nalva (Ed.): Ferroelectric Polymers – Chemistry, Physics and Applications (Marcel Dekker Inc., New York 1995) [3] V.V.

The results indicate that LaOBr:Eu3+ luminescent nanofibers are tetragonal in structure with space group P4/nmm.
[2] P Hagenmuller, Inorganic solid fluorides-chemistry and physics, Academic Press, London, 1985
[3] J Holsa, E Sailynoja, P Ylha, P Porcher, P Deren, W Stek, Analysis of the crystal structure and optical spectra of stoichiometric SmOF, Journal of Physical Chemistry 100 (1996) 14736-14744
[5] J Yang, J Gong, H Fan, L Yang, The structure and luminescence characteristics of LaOBr:Tb3+(Dy3+), Journal of Materials Science 40 (2005) 3725-3728
[8] J Lee, Q W Zhang, F Saito, Mechanochemical synthesis of LaOX(X = Cl, Br) and their solid state solutions, Journal of Solid State Chemistry 160 (2001) 469-473

Structure and Luminescence Characteristics of Yttrium Hydroxide Nanosheets Doped with Tb3+ Lin Zhang1a, Caixia Li1 ,Danyu Jiang2, Tao Feng2, Qiang Li1b 1 Department of Chemistry, East China Normal University.
The structure of layer compound and the morphology of nanosheets were determined by XRD,SEM, Zeta Size, Zeta Potential, TEM and FL.
The luminescence properties of terbium hydroxide nanosheets doped with Tb3+ were examined; the relationship between structure and spectra was discussed.
give the Scanning Electron Microscopy (SEM) picture of (Y1-xTbx)2(OH)5NO3·1.5H2O and (Y1-xTbx)2(OH)5C6H5COO·1.5H2O materials, it is obviously that after the microwave treatment the particles become Lamellar structured.
Li, Structure and Luminescence Characteristics of Yttrium Hydroxide Nanosheets Doped with Eu3+, Advanced Materials Research. 177 (2011) 269-271

To synthesize experimentally more superior derivatives of benzoxazinoids, we applied the theories of quantum chemistry to theoretical calculation for optimization of the structure of the experimentally synthesized BMIPBI, and obtained without experimental data the infrared spectrum, electronic absorption spectrum and thermodynamic properties, for the expectation of providing more information for researching the structure-activity relationship of such compounds.
Fig.1 Stable molecular structure of the BMIPBI Fig. 1 demonstrated that the molecule of BMIPBI was composed of isopropane and two side chains of 2, 4-dihydro-2H-3-(4-N-maleimade) phenyl-1, 3-benzoxazine.
Infrared spectrum of the BMIPBI molecule was obtained by frequency calculation on the basis of optimal structure, see Fig. 2.
Theoretic Study of 3-(4-N-Maleimido)-Phenyl-2, 4-dihydro-2H-1, 3-benzoxazineMolecular Structure, Spectrum and Thermodynamic Properties [J].
Physic Chemistry, Science Press, Beijing2008, 556–557.

., Mexico 3 School of Chemistry and Environment Engineering, Jianghan University, Wuhan, Hubei Province, 430056, P.
A larger (Q 2+Q 3)/Q 4 value indicates more defects in the structure or a less ordered pore system.
After calcination at 600 °C, its hexagonal structure regularity could be further enhanced.
F.Vansant: Chemistry: A European Journal Vol. 6 (2000), p. 2960
Clark: Green Chemistry Vol. 1 (1999), p.1

Special structure mainly includes directional structure of clast, leaching structure and colloid structure.
Clastic structure, leaching structure and colloidal structure demonstrate that mineralizaton process of WZD bauxite is a very complicated process.
For a long time many experts and scholars have researched on rocks and minerals, chemistry, sedimentary environment, provenance, mineralization age, and mass balance calculation of the bauxite [1-15].
Fig.2 shows main special structure in WZD bauxite.
Fig.2 Special structures of WZD bauxite Discussion Special structure of bauxite have provide information for the research of mineralization.

The Mo dopant influenced the crystal structure and phase transition of VO2 (M) particles.
Above Tc it has a tetragonal rutile structure and exhibits metallic properties, while below Tc it is a semiconductor with a monoclinic structure.
Yin, Synthesis and thermochromic properties of vanadium dioxide colloidal particles, Journal of Materials Chemistry 21 (2011) 14776
Seshadri, Controlled Reduction of Vanadium Oxide Nanoscrolls: Crystal Structure, Morphology, and Electrical Properties, Chemistry of Materials 20 (2008) 6396-6404
Chi Fo Tsang, Synthesis of reduced vanadium oxides in aqueous solutions, Journal of Materials Chemistry 8 (1998) 425-428

Participation of Calcium Phosphate Bone Substitutes in the Bone Remodeling Process: Influence of Materials Chemistry and Porosity A.
In the biomineralization processes, the bone mineral forms plate- or needle-like calcium-deficient hydroxyapatite crystals 100-150 nm in length and 10-20 nm thick (Fig. 1), and since it is less perfect in structure, and therefore, being more reactive and soluble, it facilitates chemical turnover or bone remodeling.
Material Chemistry.
These materials are able to perfectly retain the magnificent porosity present in bovine bones, but since they are sintered at temperatures above 1200°C (to safely burn out the organic residues), they simply lose the material chemistry aspects of the original bones, and they convert into well-crystallized calcium hydroxyapatite, contaminated with only trace amounts of phases like CaO, Ca3(PO4)2, and Ca4(PO4)2O.
The reason for this is so clear that at or above the stated temperature carbonate ions which may be present in the apatite structure are opt to readily leave the material [18].

On reheating the atomized powders into semisolid state, the phase chemistry and quantity of liquid were typically changed as the system established equilibrium.
Solid state homogenization heat treated at 550 °C cannot eliminate non-equilibrium structure and thus retard the formation of the liquid.
The phase chemistry and quantity of liquid changed typically after the initial liquid formation as the system establishes equilibrium [10], which is close to the equilibrium composition. the composition of the liquid is rich in solute element and the solid is solute-poor.
(2) On reheating the spray formed 7050 alloy into semisolid state, the phase chemistry and quantity of liquid will typically change as the system establishes equilibrium.

The cubic phase SBA-1 was suggested to have an ordered-3D structure with two types of globular cages, which dedicated the formation of a continuous porous network13.
These results indicated that the cage-like structure of mesoporous materials was not beneficial to the adsorption of guests.
These studies indicate that the host/guest chemistry in mesoporous materials could be conveniently processed to control the adsorption and release behavior of molecules of pharmacological interest.
Vallet-Regi: Chemistry of Materials, Vol. 15 (2003), p. 500 [6] A.
Matsukata: Chemistry of Materials, Vol. 15 (2003), p. 3385 [10] S.