scholarly journals Nucleation Kinetics, Growth and Characterization Studies of a Diamagnetic Crystal-Zinc Sulphate Heptahydrate (ZSHH)

2009 ◽  
Vol 6 (3) ◽  
pp. 871-879 ◽  
Author(s):  
R. Kanagadurai ◽  
R. Durairajan ◽  
R. Sankar ◽  
G. Sivanesan ◽  
S. P. Elangovan ◽  
...  
Keyword(s):  
Induction Period ◽  
Zinc Sulphate ◽  
Critical Nucleus ◽  
Growth Parameters ◽  
Ir Absorption ◽  
X Ray Diffraction ◽  
Nucleation Kinetics ◽  
Growth Technique ◽  
Free Energy Of Formation ◽  
Ft Ir

Solubility, metastable zone width and induction period measurements have been performed on zinc sulphate heptahydrate (ZSHH). Interfacial tension values determined from induction period measurements have been used for the evaluation of the nucleation parameters such as radius of critical nucleus and the free energy of formation of critical nucleus. ZSHH crystallizes in the orthorhombic structure. Crystals of diamagnetic zinc sulphate heptahydrate have been grown by temperature lowering solution growth technique with the optimized growth parameters. The as-grown ZSHH crystals were characterized by the powder X-ray diffraction, UV-VIS absorption and transmittance, FT-IR absorption, TG-DTA, microhardness and etching studies.

scholarly journals Preparation of Samarium Doped Calcium Hydrogen Phosphate and Study of Its Density and Thermal and Dielectric Characteristics

2014 ◽  
Vol 2014 ◽  
pp. 1-8
Author(s):  
K. K. Bamzai ◽  
Goldy Slathia ◽  
Bindu Raina ◽  
Rashmi Gupta ◽  
Seema Verma ◽  
...  
Keyword(s):  
Single Crystal ◽  
Growth Parameters ◽  
X Ray Diffraction ◽  
Hydrogen Phosphate ◽  
Monoclinic System ◽  
Dielectric Characteristics ◽  
Growth Technique ◽  
Temperature Solution ◽  
Flotation Method ◽  
Kinetics Of

Samarium doped calcium hydrogen phosphate was synthesized as single crystal by room temperature solution growth technique, namely, silica gel technique. The kinetics of the growth parameters was studied with regard to variation of pH, dopant concentration, gel ageing, and upper reactant concentration. The optimum conditions for the growth of good quality single crystal were worked out. Single crystal X-ray diffraction analysis establishes that the crystal belongs to monoclinic system. The density observed by the flotation method is greater than the density of the reported pure calcium hydrogen phosphate thereby suggesting the incorporation of the dopant (Sm) ion into the lattice of host (CHP). Thermal analysis gave two sharp endothermic peaks which are due to partial dehydration and phase transition, respectively. Dielectric studies establish a shift in the Curie temperature from 355 to 370°C only at higher frequencies thereby suggesting the relaxational behavior of the material.

Theoretical and experimental study of new nonlinear optical material nicotinohydrazide

2021 ◽  
pp. 2050007
Author(s):  
C. Deepa ◽  
M. Anbuchezhiyan ◽  
Rajendran Sribalan
Keyword(s):  
Density Functional ◽  
Level Density ◽  
Thermal Studies ◽  
X Ray Diffraction ◽  
Functional Theory ◽  
Growth Technique ◽  
Cell Parameters ◽  
B3lyp Method ◽  
Ft Ir ◽  
Uv Visible

Pyridine-3-carbohydrazide (NIH) crystal is grown by slow evaporation solution growth technique and the single crystal X-ray diffraction experiment confirms cell parameters and space group. The FT-IR and FT-Raman studies are used to identify the functional groups in the compound Nicotinohydrazide. The thermal studies are conducted using thermogravimetric analysis and differential thermal analysis, the UV–Visible transmission spectrum of NIH is recorded within the range of 400–800[Formula: see text]nm. Besides, in order to know the optical properties of the material at molecular level, density functional theory (DFT) has been employed using B3LYP method at 6-[Formula: see text] (d,p). The electric dipole moment and first-order hyperpolarizability are calculated and found to be high. The second-order NLO studies for NIH crystal are done and it is compared with KDP.

scholarly journals Growth, Nucleation Kinetics and Structural Studies on L-Valine Piperazinium Single Crystals

2019 ◽  
Vol 31 (9) ◽  
pp. 1966-1970 ◽  
Author(s):  
R. Arunkumar ◽  
D. Benny Anburaj
Keyword(s):  
Single Crystal ◽  
Room Temperature ◽  
Slow Growth ◽  
Growth Parameters ◽  
Solubility Curve ◽  
Structural Studies ◽  
Nucleation Kinetics ◽  
Growth Technique ◽  
Time Period ◽  
Temperature Induction

A single crystal of L-valine piperazinium was grown by slow growth technique. Structural studies confirm the monoclinic structure with space group P21. The solubility curve showing high soluble in water and peak shows positive solubility nature. A tiny nucleation formed at 10 ºC for room temperature process and it gradually increasing with respect process temperature. Induction period revels that time period for nucleation at constant temperature and it absorbed that in (10 ºC) 500 s for room temperature. The calculated interfacial tension values are greater than one order other amino acid based piperazinium. By using growth parameters bulk L-valine piperazinium crystal were harvested and single crystal XRD confirms that formation of L-valine piperazinium crystals.

scholarly journals Isolated α-turn and incipient γ-helix

2019 ◽  
Vol 10 (28) ◽  
pp. 6908-6914 ◽  
Author(s):  
Fatemeh M. Mir ◽  
Marco Crisma ◽  
Claudio Toniolo ◽  
William D. Lubell
Keyword(s):  
Ir Absorption ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ft Ir

The unique abilities of homo-oligo-adamantyl peptides to adopt α- and γ-turn conformations are demonstrated by X-ray diffraction, and NMR and FT-IR absorption spectroscopies.

scholarly journals The Effect of EDTA on the Nucleation Kinetics and Mechanical Properties of KDP Crystal

2012 ◽  
Vol 4 (3) ◽  
pp. 533-540
Author(s):  
A. Rahman ◽  
J. Podder
Keyword(s):  
Critical Nucleus ◽  
Nucleation Kinetics ◽  
Kdp Crystal ◽  
Growth Technique ◽  
Work Hardening Coefficient ◽  
Temperature Solution ◽  
Kinetics Of ◽  
Kdp Crystals ◽  
Hardening Coefficient ◽  
Solution Growth Technique

Potassium di-hydrogen phosphate (KDP) has been successfully grown in pure form and doped with ethylene diamine tetra acetic acid (EDTA) by low temperature solution growth technique and nucleation kinetics of KDP crystals in doped and undoped solutions were measured and analyzed. The induction period ? was measured and experiments were performed at selected degrees of supersaturation and the critical nucleation parameters like energy of formation of the critical nucleus (?G*), radius of the critical nucleus r*, nucleation rate J, number of the molecules in the critical nucleus i* have been calculated based on the classical theory of nucleation. The grown crystals have been subjected to study the mechanical property. The microhardness test was carried out on (100) plane. The load dependent hardness and work hardening coefficient was measured.© 2012 JSR Publications. ISSN: 2070-0237 (Print); 2070-0245 (Online). All rights reserved.doi: http://dx.doi.org/10.3329/jsr.v4i3.9415 J. Sci. Res. 4 (3), 533-540 (2012)

scholarly journals Crystallization Of Zinc Sulphate Single Crystals And Its Structural, Thermal And Optical Characterization

1970 ◽  
Vol 35 (2) ◽  
pp. 203-210 ◽  
Author(s):  
JK Saha ◽  
J Podder
Keyword(s):  
Zinc Sulphate ◽  
Ultra Violet ◽  
X Ray Diffraction ◽  
Pure Zinc ◽  
Good Thermal Stability ◽  
Cell Dimensions ◽  
Isothermal Evaporation ◽  
Ft Ir ◽  
Unit Cell Dimensions ◽  
Good Agreement

Zinc sulphate (ZnSO4.7H2O), an inorganic material has been crystallized by an isothermal evaporation method. ZnSO4.7H2O is highly soluble in water and the solubility is found to be increased almost linearly with the increase of temperature. At room temperature around 34°C, the solubility was found to be 92.41 gm/50 ml. The FT-IR spectroscopy was performed on pure zinc sulphate crystals to identify the presence of functional groups. The grown crystals have been subjected to powder X-ray diffraction to determine the unit cell dimensions and the crystal structure. The lattice parameters are found to be, a = 9.9810 Å, b = 7.2500 Å and c = 24.2800 Å, respectively. The values were in good agreement with those of the reported values. The TGA and DTA study revealed that the grown crystals have good thermal stability. The UV-vis spectrum showed that the material has wide optical transparency in the Ultra-violet region. Key words: Isothermal evaporation; Crystatization; Zinc sulphate; Structural characterization DOI: http://dx.doi.org/10.3329/jbas.v35i2.9426 JBAS 2011; 35(2): 203-210

The Function of Sba-15 over Ni/Mo2C Catalysts for Carbon Dioxide Reforming of Methane

2012 ◽  
Vol 455-456 ◽  
pp. 174-179 ◽  
Author(s):  
Jian Huang ◽  
T. Huang ◽  
H. Chunluan ◽  
Wei Huang ◽  
Ren Xiong Ma
Keyword(s):  
Mesoporous Silica ◽  
Atmospheric Pressure ◽  
Molybdenum Carbide ◽  
Catalytic Performance ◽  
Sem Analysis ◽  
Molar Ratio ◽  
Ir Absorption ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ft Ir

A mesoporous silica (SBA-15) was used to prepare the Ni/Mo2C catalysts in order to study the influence of the support on the catalytic performance. The catalysts were characterized by-N2adsorption, X-ray diffraction, FT-IR absorption, CO2-TPD and SEM analysis. The catalytic properties was tested at 800°C, atmospheric pressure, GHSV of 9000 ml3h-1g-1and a CH4/CO2molar ratio of 1. These results suggest that catalytic activity, which is directly related to the incorporation of nickel and molybdenum carbide to the mesoporous silica.

scholarly journals Struvite Grown in Gel, Its Crystal Structure at 90 K and Thermoanalytical Study

Crystals ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 89 ◽  
Author(s):  
Jolanta Prywer ◽  
Lesław Sieroń ◽  
Agnieszka Czylkowska
Keyword(s):  
Thermal Analysis ◽  
Sodium Metasilicate ◽  
X Ray Diffraction ◽  
Gel Growth ◽  
Growth Technique ◽  
Thermoanalytical Study ◽  
X Ray ◽  
Cell Parameters ◽  
Thermal Analysis Techniques ◽  
Derivative Thermogravimetry

In this article, we report the crystallization of struvite in sodium metasilicate gel by single diffusion gel growth technique. The obtained crystals have a very rich morphology displaying 18 faces. In this study, the habit and morphology of the obtained struvite crystals are analyzed. The crystals were examined and identified as pure struvite by single X-ray diffraction (XRD). The orthorhombic polar noncentrosymmetric space group Pmn21 was identified. The structure of the crystal was determined at a temperature of 90 K. Our research indicates a lack of polymorphism, resulting from the temperature lowering to 90 K, which has not been previously reported. The determined unit cell parameters are as follows a = 6.9650(2) Å, b = 6.1165(2) Å, c = 11.2056(3) Å. The structure of struvite is presented here with a residual factor R1 = 1.2% at 0.80 Å resolution. We also present thermoanalytical study of struvite using thermal analysis techniques such as thermogravimetry (TG), derivative thermogravimetry (DTG) and differential thermal analysis (DTA).

scholarly journals Polyurethane Composite Foams Synthesized Using Bio-Polyols and Cellulose Filler

Materials ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3474
Author(s):  
Katarzyna Uram ◽  
Milena Leszczyńska ◽  
Aleksander Prociak ◽  
Anna Czajka ◽  
Michał Gloc ◽  
...  
Keyword(s):  
Cross Sections ◽  
Raw Materials ◽  
Polyurethane Foams ◽  
Degree Of Crystallinity ◽  
X Ray Diffraction ◽  
Polyurethane Composite ◽  
Composite Foams ◽  
Closed Cell ◽  
Ft Ir ◽  
The Fourier Transform

Rigid polyurethane foams were obtained using two types of renewable raw materials: bio-polyols and a cellulose filler (ARBOCEL® P 4000 X, JRS Rettenmaier, Rosenberg, Germany). A polyurethane system containing 40 wt.% of rapeseed oil-based polyols was modified with the cellulose filler in amounts of 1, 2, and 3 php (per hundred polyols). The cellulose was incorporated into the polyol premix as filler dispersion in a petrochemical polyol made using calenders. The cellulose filler was examined in terms of the degree of crystallinity using the powder X-ray diffraction PXRD -and the presence of bonds by means of the fourier transform infrared spectroscopy FT-IR. It was found that the addition of the cellulose filler increased the number of cells in the foams in both cross-sections—parallel and perpendicular to the direction of the foam growth—while reducing the sizes of those cells. Additionally, the foams had closed cell contents of more than 90% and initial thermal conductivity coefficients of 24.8 mW/m∙K. The insulation materials were dimensionally stable, especially at temperatures close to 0 °C, which qualifies them for use as insulation at low temperatures.

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