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Morphological and FTIR Studies of Barium Oxalate Single Crystals

References 1. Raghavan, P.S.; Ramasamy, P. Crystal Growth Process and Methods ; KRU publication, Kumbakonam, India, 2000 . 2. Ronda, C.R.; Jüstel, T.; Nikol, J. Rare Earth Phosphors: Fundamentals and Application, J. Alloys . Comp. 1998 , 275-277 , 669-676. 3. Basharat, W.; Feroz, D. Growth and Characterization of Holmium Oxalate Heptahydrate Crystals. J. Cryst. Proc. Tech. 2012 , 2 , 137-141. 4. Vanhoyland, G.; Bouree, F.; Van Bael, M.K.; Mullens, J.; L.C. Van Poucke. Structural determination of refinement of acid strontium

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Effect of macromolecular mass transport in microgravity protein crystallization

determinations. Data and information obtained from crystallographic investigations are important for macromolecular engineering to optimize biomolecules for various applications in biomedical research. Macromolecular transport in crystallization processes has been shown to directly affect crystal quality ( García-Ruiz et al., 2016 ; McPherson et al., 1999 ; Vekilov, 1999 ). Gravity-dependent flow effects, including convection and sedimentation, affect the crystal growth processes on earth ( Lee and Chernov, 2002 ; Otálora et al., 2001 ; Wilcox, 1983 ). Density

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An in Situ Crystal Growth of Metal Organic Frameworks-5 on Electrospun PVA Nanofibers

media. international journal of hydrogen energy, 40 (30), 9382-9387. [16] Jin, R., Bian, Z., Li, J., Ding, M., Gao, L. (2013). ZIF-8 crystal coatings on a polyimide substrate and their catalytic behaviours for the Knoevenagel. Dalton Transactions, 42 (11), 3936-3940. [17] Lian, Z., Huimin, L., Zhaofei, O. (2014). In situ crystal growth of zeolitic imidazolate frameworks (ZIF) on electrospun polyurethane nanofibers. Dalton Transactions, 43 (18), 6684-6688. [18] Laurila, E., Thunberg, J., P. Argent, S., R. Champness, N., Zacharias, S., Westman, G

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Investigation on optical, electrical and etching properties of 2-aminopyridinium 4-aminobenzoate: A phase matchable organic single crystal for optoelectronic device applications

-aminobenzoic acid were used without further purification for material synthesis. The two reactants were dissolved separately with 1:1 molar ratio in methanol and mixed together. The resulting solution was stirred well for about 30 minutes. The obtained microcrystalline product was filtered and then purified by repeated recrystallization process in methanol. The recrystallized compound was used for single crystal growth by the solvent evaporation technique. 2.2 Crystal growth It is easy to grow APAB single crystals of optical quality using a standard slow evaporation

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Synthesis and formation process of zirconium dioxide nanorods

Abstract

Crystalline zirconium dioxide nanorods have been prepared by a simple hydrothermal process using zirconium hydroxide as the zirconium raw material. Zirconium dioxide nanorods are composed of monoclinic zirconium dioxide phase, which has been confirmed by the X-ray diffraction analysis. Electron microscopy observations show that the zirconium dioxide nanorods have a single crystal structure, with the rod diameter of less than 100 nm and length of 1–2 μm. Hydrothermal temperature and reaction time play essential roles in the formation and growth of the zirconium dioxide nanorods. Nucleation and crystal growth process are proposed to explain the formation and growth of the zirconium dioxide nanorods.

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The Kinetic Study of The Hydrothermal Growth of Zno Nanorod Array Films / Zno Nanostieņu Kopu Pārklājuma Hidrotermālās Augšanas Kinētikas Izpēte

). Kinetic study on Zn(O,OH)S thin films deposited by chemical bath deposition. Electrochimica Acta, 55, 5610-5616. 15. Singh, R.G., Singh, F., Kumar, V., and Mehra, R.M. (2011). Growth kinetics of ZnO nanocrystallites: Structural, optical and photoluminescence properties tuned by thermal annealing. Current Applied Physics, 11, 624-630. 16. Bouhssira, N., Aida, M.S., Mosbah, A., and Cellier, J. (2010). Isothermal crystallization kinetic of ZnO thin films. Journal of Crystal Growth, 312, 3282-3286. 17. Ko, H.H., Hsi, C

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Magnetic properties of manganese doped PrAlO3 monocrystalline fibres

Abstract

Monocrystalline fibres of undoped PrAlO3 and PrAlO3:0.1 Mn, have been grown by the pulling-down method under nitrogen atmosphere. The as-grown crystal doped with Mn had a visible brown core surrounded by a green ring, whereas this effect was weaker for the undoped PrAlO3. A coloration of the brown core was caused by a presence of Pr4+ ions. The presence of the Pr4+ ions was confirmed by XPS and magnetic studies. The XPS chemical analysis showed the increased concentration of oxygen in the crystals with the brown core. The most probable valency of manganese is Mn4+. It is located in Al3+ sites.

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Effect of heat-treatment on grain growth of nanocrystalline tricalcium phosphate powder synthesized via the precipitation method

Abstract

Nanocrystalline tricalcium phosphate powder was synthesized via the solution-precipitation method followed by heat treatment in order to achieve phase evolution, which was then studied by XRD and TEM techniques. The crystallites sizes were estimated by the Scherrer method and results were confirmed by TEM micrographs. The experimental observations showed that nanocrystalline tricalcium phosphate can be successfully prepared from raw materials by the precipitation technique. This technique is a competitive method for nanocrystalline tricalcium phosphate synthesis compared to other techniques. Moreover, a simple kinetic growth investigation was performed on the nanocrystalline growth process during heat treatment. Results have shown growth rate to increase exponentially with temperature and the growth rate constants to increase with time. The average activation energies of tricalcium phosphate grain growth obtained by this method were 84.78 and 134.38 KJ/mol.

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Chemical modification of TiO2 by H2PO4−/HPO42− anions using the sol-gel route with controlled precipitation and hydrolysis: enhancing thermal stability

Abstract

Two titanium phosphate materials (TpP and ThP) have been successfully synthesized by sol-gel route with controlled precipitation and hydrolysis. The TpP material was obtained from the reaction between precipitated titania and phosphate buffer solution H2PO4− /HPO42− (pH = 7.3). The TpP material was prepared through hydrolysis of titanium in the presence of H2PO4−/HPO42. The probable state of the phosphate anions in titania framework and their effect on the anatase-to-rutile transformation were characterized by ICP-AES, DTA-TG, 31P NMR, FT-IR, and Raman analysis HRTEM/SEM. FT-IR and 31P NMR analyses of titanium phosphate TpP calcined at low temperature showed that the phosphate species existed not only as Ti-O-P in the bulk TiO2 but also as amorphous titanium phosphates, including bidentate Ti(HPO4)2 and monodentate Ti(H2PO4)4. Increased calcination temperature only gave an enrichment of bidentate structure on the titania surface. For the TpP material, H2PO4−/HPO42− anions were introduced into the initial solution, before precipitation, what promoted their lattice localization. At high temperatures, all the phosphorus inside the bulk of TiO2 migrated to the surface. The Raman analysis of both samples showed that the bidentate phosphates increased the temperature of the anatase-to-rutile phase transformation to more than 1000 °C with the formation of well crystalline TiP2O7 phase. This phenomenon was more evident for TpP sample.

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Growth of large SbSI crystals

Abstract

In this paper a novel method of SbSI single crystals fabrication is presented. In this method a sonochemically prepared SbSI gel is used as an intermediate product in a vapour growth process. The main advantages of the presented technique are as follows. First, the SbSI gel source material has lower temperature of sublimation and allows to avoid explosions during SbSI synthesis (the sonochemical synthesis is free of any explosion hazard). Second, but not least, the grown SbSI single crystals have smaller ratio of longitudinal and lateral dimensions. The cross sections of the presented crystals are relatively large (they are up to 9 mm2). The crystals have been characterized by X-ray diffraction, angle-resolved optical spectroscopy, and diffusive reflectivity.

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