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The soil chemistry is also a contribution factor to the SiO2 content of the rice husk ash (RHA).
When rice husk is burnt in a controlled temperature, during thermal decomposition of organic matter, leaving a highly porous and nano structured particles of silica.
This gives the more porous and loose flaky morphological structure of SiO2, which is active in nature due to its high surface area obtained because of its nano size..
When the rice husk burnt beyond 500°C there is start of crystallization in the rice husk SiO2, which makes the structure becomes more defined or ordered [14].
Though there are slight variations on the peak position the maximum peaks matches with that of the earlier work done by the researcher displaying the presence of nano structured SiO2.

Introduction Titanium dioxide nano-structures have attracted much attention for several applications such as solar cell, photocatalyst and gas sensors.
It is believed that photo-activity depends on the surface area and crystalline structure which is affected by the preparation procedure [4-5].
Results and Discussion Structure analysis.
FESEM, XRD, Spectrophotometry method were employed to investigate nanofibers structure.
Miyauchi, N-doped TiO2 nanotube with visible light activity, J.Chemistry Letters 33 (2004) 1108-1109

The rate of refinement of the internal structure (particle size, crystalline size domain, lamellar spacing, etc.) is roughly logarithmic with processing time and therefore the size of the starting particles is relatively unimportant.
Van Tendeloo, An Electron and X-Ray Diffraction Investigation of Ni1+xTe2 and Ni1+xSe2CdI2/NiAs Type Solid Solution Phases, Journal of Solid State Chemistry 161 (2001) 266-273
Brus, Synthesis, Stabilization, and Electronic Structure of Quantum Semiconductor Nanoclusters, Ann.
Von Dreele, General Structure Analysis System (GSAS), Los Alamos National Laboratory Report LAUR 86-748 (2000)
[11] Inorganic Crystal Structure Database (ICSD), Gmelin-Institut für Anorganische Chemie and Fachinformationszentrum, FIZ, Karlsruhe, (2007).

Among them, hydrothermal synthesis is an effective and convenient process for preparing MnO2 with desirable crystal structures, particle size, morphologies and defect chemistry [2].
The morphology and structure of the MnO2 powder were investigated, as shown in Fig. 2.
The MnO2 has a fine laminated structure and is about 5-10 nm in thickness seen from Fig. 2d.
Wang, Preparation and capacitive property of manganese oxide nanobelt bundles with birnessite-type structure, J.
Ma, Self-template route to MnO2 hollow structures for supercapacitors, Mater.

Self-assembly Behavior of N-Methly-N-Hexadecyl- Pyrrolidinium Bromide in Water Jinhua He, Cuihua Li*, Lian’an Qian, Jianhong Liu and Qianling Zhang College of Chemistry and Chemical Engineering, Shenzhen University, Shenzhen, China Email: licuihuasz@163.com Keywords: N-methyl-N-hexadecylpyrrolidinium bromide; lyotropic liquid crystalline; self-assembly; SAXS Abstract.
We report herein the phase transitions, self-assembly processes, and liquid crystal structures based on N-methyl-N- hexadecylpyrrolidinium bromide (IL) in water by combining polarizing optical microscope (POM), differential scanning calorimetry (DSC), small-angle X-ray scattering (SAXS).
The exact phase structure can be recognized with SAXS measurements as a function of composition.
There is only a very weak peak centered at 1.31 nm-1 when the IL concentration is 30%, which is ascribed to self-assembly into a rod micelle structure about 4.79 nm [7].
With increasing the content of the IL from 35% to 70% (Fig. 3b and Table 1), the enthalpy changes of the second transition increase, indicative of more cylindrical crystal structure.

But this contradicts the opinion of some authors that the effect of cooling rate is not important for microstructure and the chemistry ( complex alloying effects) controls the grain growth mainly[8-9].
Furnace cooling from the single phase (disordered a phase) or two-phase region (disordered α and β phases) generally results in a FL structure where the lamellae are mostly γ intermixed with α2 lamellae.
Slow cooling (with cooling rates of 15–100 _C/min) results in a two phase lamellar structure consisting of different orientations of lamellae ofγand some α2 lamellae.
It means the lamellar structure is more homogenous because of Gd addition.
The grain size of the lamellar structure falls into the hundreds of micrometer range and is refined with increasing cooling rate. 2.

The forming of coagulated structure follows determined by conditions necessary for gel precipitation.
The major shrinkage can be described as structure densification by viscous sintering.
The storage modulus evaluation represents structure hardening up to 600°C despite of degradation due to dehydration at 200°C (Fig. 2).
Glukhovsky: Soil Silicate Articles and Structures ( Budivelnyk Publisher, Ukraine, Kiev 1967), p. 156 [4] J.
– A re-examination of existing results, Chemistry of Materials 17 (2005), p. 3075-3085 [8] P.

The ability to tune bioactivity via surface chemistry will provide much greater flexibility than that available by choice of microstructure alone.
It was found that the structure of coatings was corresponding to that of typical plasma sprayed coatings.
There are two models described the structure of α-SiOx.
And the structure is better described by RBM if x < xk and by BMM if x > xk.
Canham, Bioactitive silicon structure fabrication through nanoetching techniques, Adv.

Andrade2* 1Federal University of Campina Grande, Department of Materials Engineering, 58429-900 Campina Grande, PB - Brazil 2Federal University of Bahia, Institute of Chemistry, Campus of Ondina, 40190-270 Salvador, BA - Brazil.
A variety of oxides has been reported but the high activity and thermostability of the Fe-based HTS is apparently related to the spinel structure of the iron oxides, allowing the incorporation of promoters [7].
Accordingly, the catalyst undergoes successive redox cycles by H2O and CO to produce H2 and CO2 over a Fe2+ and Fe3+ redox pair occupying octahedral sites in the spinel structure [14, 15].
The role of a structural promoter is to provide new active sites or to modify the electronic structure of the parent catalyst in order to improve its catalytic activity.
The origin of the higher catalytic activity of the NiFe2O4 was assigned to the inverse spinel structure (γ=0.9) and to the presence of metallic nickel, formed as consequence of the high temperature reached in the reaction and by character redox of the glycine fuel.

A Potential Precipitating Apparatus and its Performance Measuring Shi ling*1.2 a, Yang chengwu1.2 a,Yu xinming1, Luo xianwei3, Chen Hongmei 1.2 1School of chemistry and environmental engineering, Jianghan University, Hubei Wuhan 430056, P.
Structure and parameters of the dust control apparatus The mechanism of the gravity, centrifugal force, collision, interception, electrostatic force and filter for dust control is applied extensively present.
Special structure should be formed to utilize one or more mechanism of these in precipitator.
Table 1 The structure parameters of the disc No.
The pressure drop is less than 900 Pa. it is obvious characteristics that the centrifugal net disc has simple structure, lower pressure drop and higher dust collection efficiency.