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Vinayagamoorthyd Department of Chemistry, Annamalai University, Annamalainagar 608002 akarunakaranc@rediffmail.com (corresponding author), bmagesh.ambi@gmail.com, cchemgomathi@rediffmail.com, dchemvina@gmail.com Keywords: Sol-gel method, photocatalysis, photodegradation, nanoparticle Abstract:Al2O3-TiO2 and ZrO2-TiO2 nanocomposites have been prepared by sol-gel method using polyvinylpyrrolidone-polyethylene glycol (PVP-PEG) as templating agents.
While Al2O3 in the former is of end-centered monoclinic crystal structure ZrO2 in the latter is a 4:1 blend of monoclinic and tetragonal phases.
The stated three dyes are of different molecular structures and belong to three different classes; methyl orange is an azo dye, methylene blue is a heterocyclic dye and rhodamine B is a xanthen dye.
Lang, Enhanced photocatalytic degradation of dye pollutants under visible irradiation on Al(III)-modified TiO2: structure, interaction, and interfacial electron transfer, Environ.

XRD measurements reveal the formation of well-crystallized orthorhombic tin mono-sulphide nanoparticles which may be considered as a distorted NaCl structure.
Ag2S), solar energy materials (ZnS, CuInS2), high-energy density batteries (TiS2) and other opto-electric and magnetic applications, of which Tin sulphides, a class of IV-VI semiconductors, belong to materials which exhibit variable physio-chemical properties, such as polytypism, polymorphism and non-stoichiometry.[4] They show a variety of phases such as SnS, Sn2S3, Sn3S4, Sn4S5 SnS2 owing to the versatile coordinating characteristics of tin and sulphur.[3,5,6] Among the IV–VI group semiconductors, research on tin monosulphide (SnS) has geared up due to its layer property and being a less toxic compound compared to other similar materials such as lead and cadmium compounds.[7-8] Being a narrow bandgap semiconductor having a band gap of 1.32–1.5 eV for direct transitions and 1–1.3 eV for indirect transitions,[9-10]it has several optoelectronic applications such as holographic recording, near infrared detector, solar absorber and the Hall effect.[11] SnS adopts a strongly distorted NaCl structure
with double layers of tightly bound Sn-S atoms with the bonding between layers of Vanderwaal type.[6,12-14] Also the orthorhombic herzenbergite modification of SnS possesses a layered structure consisting of six membered rings, a structural analogue of black phosphorous.[5]Nanoscale SnS can be synthesized withdifferent size and shape such as nanoflowers,[9] nanosheets,[10] Quantum dots,[14] nanobelts,[15] nanowires,[16] etc., using mechanochemical route,[4] Hydrothermal process,[9] precipitation method,[14] solvothermal technique,[15] two-step process,[17] chemical solution dispersion method,[18] and many more.
[6] Xing-Long Gou, Jun Chen, Pan-Wen Shen, Gou, Synthesis, characterization and application of SnS x (x= 1, 2) nanoparticles, Materials Chemistry and Physics 93 2 (2005) 557-566

Halloysite nanotubes (HNTs), the naturally formed mineral clays with hollow tubular structures, have found promising applications as nanocarriers for drug delivery systems due to their biocompatibility and nontoxicity.
One versatile nanocarrier that offers great potential for drug delivery is halloysite nanotube (HNT), an aluminosilicate dioctahedral 1:1 clay mineral structure of the formula Al2(OH)4Si2O5.nH2O.
This unique surface chemistry of HNT allows it to load different active compounds for various applications such as biocatalytic, biosensing, pharmaceutical, agricultural, environmental [2], and self-healing film applications [4].
The TEM images (Figure 3) of pure HNT and modified HNTs loaded with aspirin (HNT-STS-ASP and HNT-SLES-ASP) show that pure HNT has a tubular or cylindrical structure with a well-defined open-ended lumen.

TiO2 structures can be nanoparticles, nanotubes, nanowires, nanorods etc. depending on synthesis method and controlling parameter.
This is believed to be due to the shapeless amorphous TiO2 particles which cannot provide a homogeneous mesoporous inner structure for the film [12].
The above observation implies that the capability of absorbing light radiance is structure-properties related.
Thus, optimization of the morphology, surface structure, crystallite size and crystallinity is critical in order to improve the overall efficiency of DSC.
Photobiol A: Chemistry Vol. 164 (2004), p. 3 [4] J.

Depending on the chemical compositions of the high-speed steels grades the stoichiometry of the carbides revealed in a solidified structure has been previously reported as M6C, M2C, M7C3, M23C6, and MC [3-5].
Among these carbides, the MC type carbides, differing significantly from the other carbides in melting temperature and hardness, play a very important role in the high-speed steel structure formation.
Due to the extremely high melting temperature, MC carbides can precipitate from the melt at first as fine solid particles that additionally increases the number of nuclei in the melt [6] resulting finally in the solidified structure refinement.
The rate of these changes was found to depend on the steel chemistry resulting finally in the different microstructural varieties (Figs. 3d and 3e).
On the other hand, in the steel 6 alloyed with boron, upon conditions of the carbon deficit intermetallic compounds were found to form in the tempered structure.

Introduction In recent years, mesoporous silica materials, which have several advantages such as highly regular porous structure, high surface area and pore volume, low cytotoxicity and good biocompatibility [1], high thermal and hydrothermal stability [2], have been widely used in biochemistry as immobilization supports for enzymes [3].
This type of morphology has been proven to have long-range channels with the 2D-hexagonal structure directions parallel to the long axis [11].
This is clear evidence that a hexagonal structure is maintained during the functionalization procedure, suggesting that the APTES complex is embedded uniformly within the mesopores.
It seems that NH-15/SBA-15 (Fig. 3D) has the poorest-ordered long range structure.
There is partial collapse of the ordered mesoporous arrangement inside the sample, which can be regarded as worm-like structure pore; but still there are some domains with hexagonal structure at the channel opening.

Results and Discussion The structure of obtained CCHS is shown in Fig 1.
Due to free (without extra pressure) clay particles adjoining the CCHS walls, and pronounced protrusions form porous structure (Fig. 1 b).
LAC materials FGW-B, FGG-B and KER-B have the same structure and are shown in Fig. 2 e and f by a KER-B specimen.
Korjakins, Alkali-silica reactivity of foam glass granules in structure of lightweight concrete, Construction and Building Materials. 47 (2013) 274-281
Bumanis, Concrete with microfiller obtained from recycled lamp glass,10th International Conference Modern Building Materials, Structures and Techniques. (2010) 280-284

Steel are characterized by the disperse structure increased by the resilience to contact fatigue damages, the minimum roughnesses on the surface of driving.
The estimated structure and results of the X-ray phase analysis are given in tables 1 and 2.
Table 1 - Estimated structure and results of the X-ray phase analysis of system V2O5– C – Si Experience Estimated structure Results of the analysis 1 С – 1.1; VC – 94.0 prevails V8C7, 2 SiO2 – 43.4; VO-43.9; V5Si3 – 12.7 V5Si3, a little Si 3 SiO2 – 42.5; VO – 0.17; V5Si3 – 7,88; VSi2 -49.44 Si, VSi2 4 SiO2 – 38.3; VO – 0.4; VC – 48.7; SiC – 4.9; V5Si3 – 7.7 V8C7, β - SiC, VCxOy, Si3V5 5 SiO2 – 39.6; VO – 0.3; SiC – 11.8; V5Si3 – 48.2 β­SiC, V5Si3, VСхОу, V8С7, 6 SiO2 – 30.8; VO – 69.0 prevails VCxOy Table 2 - Results of the X-ray phase analysis of products of restoration of vanadic slag Experience Phase structure 1 X-ray amorphous substance, V8C7, α- Al2O3, α- Fe, Fe3C, 2 α- Fe, VC 3 α- Fe, is present VC 4 X-ray amorphous substance, V8C7, α- Fe 5 α- Fe, is present VC, a little impurity (possibly V8C7) 6 V8C7, α- Fe, X-ray amorphous substance 7 VC, α- Fe, X-ray amorphous substance 8 X-ray amorphous substance, α- Fe, VC 9 α- Fe, is present VC, V8C7.
Were a part of initial materials carbon steel of the following structure of 0.27%, 0.49% of Mn, 0.02% of Si, 0.02%V, converter vanadic slag, reducers, lime.
Mogilny, Use of vanadium for increase in operational firmness of rails at negative temperatures, Chemistry, technology and use of vanadium: theses of reports of the IX All-Russian conference, (2004) 27 – 28

When calcined at 300℃, the halloysite only removed adsorbed water and crystal water that have no effect on the basic structure.
The microstructure had little change and still keep tubular structure, but the length of the tube was 0.3-1um shorter.
The fracture of the tubular structure would inevitably result in specific surface area and pore volume increase, and then enhanced the adsorption property of samples, which will conducive to subsequent trials.
When calcined at 300 ℃ for 2h, the microstructure had little change and still keep tubular structure, but the length of the tube was 0.3-1um shorter.
Chemistry Letters, 2004, 33(5):510-511

Main Part The walnut shell structure peculiarities study and its crushability [6,7] revealed the following features: 1.
Plant residues have internal cavities in their structure, which leads to a noticeable material swelling when saturated with water [9].
This also leads to an excessively loose structure of the obtained samples.
The structure is denser.
Shcheglov, Chemistry of wood and polymers, SI, Moscow,1980