scholarly journals Thermal analysis of formation of nano-crystalline BaTiO3 using Ba(NO3)2 and TiO2

2015 ◽  
Vol 9 (4) ◽  
pp. 181-185 ◽  
Author(s):  
Jawed Ansaree ◽  
Shail Upadhyay
Keyword(s):  
Thermal Analysis ◽  
Weight Loss ◽  
Mixing Time ◽  
Nitrogen Atmosphere ◽  
Differential Scanning Calorimetric ◽  
X Ray Diffraction ◽  
X Ray ◽  
Batio3 Powder ◽  
Nano Crystalline ◽  
Ftir Technique

The reaction of Ba(NO3)2 with TiO2 was studied by thermogravimetric (TG) and differential scanning calorimetric (DSC) techniques up to 1000?C and in nitrogen atmosphere. It was found that the formation of BaTiO3 takes place above 600?C and that precursor mixing time and heating rate have no effect on the reaction temperature. BaTiO3 powder was prepared by calcination of Ba(NO3)2 and TiO2 precursor mixture at 800?C for 8 h. X-ray diffraction analysis of the synthesized BaTiO3 confirmed the formation of tetragonal phase with lattice parameters a = 3.9950?0.0003? and c = 4.0318?0.0004?. Thermal analysis of the synthesized BaTiO3 powder showed weight loss within temperature range 40-1000?C of only 0.40%. This small amount of weight loss was connected with some impurity phase, and identified as BaCO3 using Fourier transform infrared (FTIR) technique.

Study on the Synthesis of Nano-Crystalline Mg2SiO4 Powders by Aqueous Sol-Gel Process

2013 ◽  
Vol 538 ◽  
pp. 142-145 ◽  
Author(s):  
X.F. Chen ◽  
J. Li ◽  
T.T. Feng ◽  
Y.S. Jiang ◽  
X.H. Zhang ◽  
...  
Keyword(s):  
Thermal Analysis ◽  
Sol Gel ◽  
Magnesium Nitrate ◽  
Metal Alkoxides ◽  
X Ray Diffraction ◽  
Calcination Process ◽  
X Ray ◽  
Nano Crystalline ◽  
Sol Gel Process ◽  
Scanning Electron

The forsterite-structure Mg2SiO4 was successfully synthesized by the aqueous sol-gel method using Si sols dioxide and magnesium nitrate as starting materials instead of expensive organic solvent and metal alkoxides. The as-prepared nanopowders were characterized by X-ray diffraction (XRD), differential thermal analysis (DTA) and scanning electron microscope (SEM), respectively. The results showed that the calcination process of gel consisted of a series of oxidation and combustion reactions, accompanied by significantly exothermal effects. Highly reactive nanosized Mg2SiO4 powders were successfully obtained at 850 °C with particle size of 60~80 nm.

scholarly journals Synthesis, characterization, and thermal behavior of amidosulfonates of transition metals in air and nitrogen atmosphere

2020 ◽  
Vol 45 (4) ◽  
pp. 32-39
Author(s):  
Jose Marques Luiz ◽  
Ronaldo Spezia Nunes
Keyword(s):  
Thermal Analysis ◽  
Infrared Absorption ◽  
Elemental Analysis ◽  
Nitrogen Atmosphere ◽  
Direct Reaction ◽  
Infrared Absorption Spectroscopy ◽  
X Ray Diffraction ◽  
X Ray ◽  
Metal Carbonate ◽  
Dta Curves

The amidosulfonates of Mn2+, Co2+, Ni2+, Cu2+ and Zn2+ were prepared by the direct reaction between the metal carbonate and the amidosulfonic acid with heating and stirring. The compounds were characterized by infrared absorption spectroscopy (IRFT), elemental analysis, thermal analysis (TG and DTA) and X-ray diffraction by the powder method. The absorptions observed in IR spectra are associated with N-H and O-H stretching, as well as symmetrical and asymmetric S-O stretching in the sulfonic group. The compounds present X-ray diffraction pattern with well-defined reflections, showing no evidence of isomorphism. The TG-DTA curves allowed to establish the stoichiometry of compounds as M(NH2SO3)2.xH2O, where M = Mn2+, Co2+, Ni2+, Cu2+ and Zn2+ and x ranging from 1 to 4. Dehydration leads to the formation of stable anhydrous. In all cases the respective sulfates are formed as an intermediate. After consecutive steps of decomposition, the respective oxides were obtained: Mn3O4, CoO, NiO, CuO and ZnO. The TG-DTA curves are characteristic for each sample, with thermal events related to dehydration and ligand decomposition.

scholarly journals Study of structures and properties of ZnO-Sb2O3-P2O5-Na2O glasses

2014 ◽  
Vol 32 (3) ◽  
pp. 414-418 ◽  
Author(s):  
Yajun Qi ◽  
Zhiqiang Wang ◽  
Shangru Zhai ◽  
Shuwen Jiang ◽  
Hai Lin
Keyword(s):  
Thermal Stability ◽  
Thermal Analysis ◽  
Weight Loss ◽  
Deionized Water ◽  
Structure And Properties ◽  
X Ray Diffraction ◽  
X Ray ◽  
Good Thermal Stability ◽  
Structures And Properties ◽  
Thermal Stability Of

AbstractThe influence of ZnO substitution by 0–12 wt.% Na2O on the properties of ZnO-Sb2O3-P2O5-Na2O glasses has been investigated. The structure and properties of the glasses with the composition of (13.86-x)ZnO-57.93Sb2O3-28.21P2O5−x Na2O (x = 0–12 wt.%) were characterized by infrared spectra (IR), X-ray diffraction and differential thermal analysis (DTA). The results of IR indicated an increase in the intensity of symmetric vibrations of P-O-P bond, which was confirmed by the improvement of water durability with the increasing amount of Na2O in the range of 0–10 wt.%. Substitution of 10 wt.% Na2O led to the weight loss of the glass to 5.93 mg/cm−2 after immersion in deionized water at 50 °C for 24 h. The results of XRD showed that the ability of crystallization decreased, indicating the good thermal stability of the glass. The glass containing 8 wt.% Na2O had the best properties in every respect and might be an alternative to lead based glasses for the applications, providing further composition improvement.

Preparation and Magnetic Properties of Nanocrystalline (Fe,Cr)-N

2012 ◽  
Vol 625 ◽  
pp. 222-225
Author(s):  
Wen Jiang Feng ◽  
Chuan Yin Wang ◽  
Hao Hua Zhang
Keyword(s):  
Crystal Structure ◽  
Solid Solution ◽  
Magnetic Properties ◽  
Magnetic Moment ◽  
Single Phase ◽  
Nitrogen Atmosphere ◽  
X Ray Diffraction ◽  
X Ray ◽  
Nano Crystalline ◽  
Intrinsic Magnetic Moment

The nano-crystalline (Fe,Cr)N was prepared as a single phase by milling Fe80Cr20 in a nitrogen atmosphere. Its crystal structure is determined to be the cubic rock salt-type CrN by X-ray diffraction measurements. The nano-crystalline is stable up to above 773 K and decomposes into (Fe,Cr)N and Fe-Cr solid solution. Due to the combination of Fe atoms and N ones, the intrinsic magnetic moment of Fe atoms is reduced, which is confirmed by our measurements.

scholarly journals Structural changes of Cr-beidellite treated up to 1350 °C in oxygen or nitrogen atmospheres

Cerâmica ◽  
2018 ◽  
Vol 64 (369) ◽  
pp. 64-68
Author(s):  
H. S. Santos ◽  
A. M. Cesio ◽  
M. Gauna ◽  
V. F. Justo ◽  
C. Volzone
Keyword(s):  
Thermal Analysis ◽  
High Temperature ◽  
Thermal Treatment ◽  
Structural Changes ◽  
Pillared Clay ◽  
Nitrogen Atmosphere ◽  
Thermal Treatments ◽  
X Ray Diffraction ◽  
X Ray ◽  
Mineralogical Phases

Abstract Beidellite clay mineral after intercalation of OH-Cr(III) species were thermally analyzed up to 1350 °C in oxygen and nitrogen atmospheres. OH-Cr-beidellite can be used as a pillared clay precursor for catalysis or as adsorbent applications. However, in this paper beidellite enriched in chromium were analyzed at different thermal treatments up to high temperature for evaluating structural changes for possible future ceramic applications. The structural changes were followed by thermal analysis and X-ray diffraction. The thermal treatment of OH-Cr-beidellite in oxygen and nitrogen atmospheres developed different mineralogical phases up to 1050 °C, but at higher temperatures, the same phases were developed in both atmosphere treatments. Eskolaite phase (Cr2O3) appeared in the sample after heating at 400 °C in oxygen atmosphere, whereas grimaldite (CrO-OH) in nitrogen atmosphere, maintaining the starting phases. At 1000 °C the raw clay minerals disappeared, as it is knew. At 1050 °C in nitrogen atmosphere, grimaldite was absent and eskolaite appeared. At 1350 °C in the samples calcined in both atmospheres, quartz, cristobalite and mullite as the main phases and in lower contents aluminum oxide and aluminum-chromium oxide [(Al,Cr)2O3] were present.

Room temperature reduction of scheelite (CaWO4)

1999 ◽  
Vol 14 (2) ◽  
pp. 619-627 ◽  
Author(s):  
N. J. Welham
Keyword(s):  
Thermal Analysis ◽  
Tungsten Carbide ◽  
Room Temperature ◽  
Isothermal Annealing ◽  
Fine Powder ◽  
Nitrogen Atmosphere ◽  
X Ray Diffraction ◽  
Pure Tungsten ◽  
X Ray ◽  
Tungsten Metal

A mixture of scheelite and magnesium has been mechanically milled together for 100 h, either with graphite or in a nitrogen atmosphere, with the intention of forming tungsten carbide or nitride. The resultant powders were examined by thermal analysis, isothermal annealing, and x-ray diffraction to determine the effect of milling on the reduction of scheelite. With graphite, nanocrystallite W2C was the exclusive tungsten product; WC was not detected even after annealing at 1000 °C. No nitride formed in the system milled with nitrogen; however, 10 nm crystallites of elemental tungsten were formed. The unwanted phases, MgO and CaO, were readily removed by leaching in acid, leaving a fine powder composed of impact welded aggregates of either carbide or 99% pure tungsten metal.

PENINGKATAN LAJU DISOLUSI ACYCLOVIR DENGAN METODE SISTEM DISPERSI PADAT MENGGUNAKAN POLOXAMER 188

2016 ◽  
Vol 5 (1) ◽  
pp. 6
Author(s):  
Budi Setiawan ◽  
Erizal Zaini ◽  
Salman Umar
Keyword(s):  
Electron Microscopy ◽  
Thermal Analysis ◽  
Scanning Electron Microscopy ◽  
Fourier Transform ◽  
Differential Thermal Analysis ◽  
Fourier Transform Infrared ◽  
X Ray Diffraction ◽  
Poloxamer 188 ◽  
X Ray ◽  
Scanning Electron

Sebuah penelitian tentang sistem dispersi padat dari asiklovir dengan poloxamer 188 telah dilakukan formulasi dengan pencampuran secara fisika dengan rasio 1 : 1, 1 : 3, 1 : 5 dan dispersi padat 1 : 1, 1 : 3, 1 : 5 dan penggilingan 1:1 sebagai pembanding. Dispersi padat dibuat menggunakan metode pencairan (fusi), yang digabung dengan poloxamer 188 pada hotplate kemudian asiklovir dimasukkan ke dalam hasil poloxamer 188 lalu di kocok hingga membentuk masa homogen. Semua formula yang terbentuk termasuk asiklovir poloxamer 188 murni dianalisis karakterisasinya dengan Differential Thermal Analysis (DTA), X-ray Diffraction, Scanning Electron Microscopy (SEM), dan Fourier Transform Infrared (FTIR), kemudian pengambilan dilakukan  (penentuan kadar) mengunakan spektrofotometer UV pada panjang gelombang 257,08 nm dan uji laju disolusi dengan aquadest bebas CO2 menggunakan metode dayung. Hasil pengambilan  (penentuan kadar) menunjukkan bahwa semua formula memenuhi persyaratan farmakope Amerika edisi 30 dan farmakope Indonesia edisi 4 yaitu 95-110%. Sedangkan hasil uji laju disolusi untuk campuran fisik 1: 1, dan dispersi padat 1: 1, dan penggilingan 1: 1 menunjukkan peningkatan yang nyata dibandingkan asiklovir murni. Hal ini juga dapat dilihat dari hasil perhitungan statistik  menggunakan analisis varian satu arah  SPSS 17.

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).

Synthesis, crystal structure, luminescence, and photocatalytic properties of a 2D Cu(II) metal-organic frameworks based on 3,5-di(1H-benzimidazol-1-yl)pyridine and 4,4′-oxybis(benzoate) ligands

2020 ◽  
Vol 75 (8) ◽  
pp. 727-732
Author(s):  
Chen Zhang ◽  
Jian-Qing Tao
Keyword(s):  
Crystal Structure ◽  
Thermal Analysis ◽  
Uv Light ◽  
Metal Organic Framework ◽  
Metal Organic Frameworks ◽  
X Ray Diffraction ◽  
X Ray ◽  
Uv Light Irradiation ◽  
Photocatalytic Activities ◽  
Metal Organic

AbstractA new Cu(II) metal-organic framework, [Cu(L)(OBA)·H2O]n (1) [H2OBA = 4,4′-oxybis(benzoic acid), L = 3,5-di(1H-benzimidazol-1-yl)pyridine] was hydrothermally synthesized and characterized through IR spectroscopy, elemental and thermal analysis and single-crystal X-ray diffraction. Complex 1 is a four-connected uni-nodal 2D net with a (44·62) topology which shows an emission centered at λ ∼393 nm upon excitation at λ = 245 nm. Moreover, complex 1 possesses high photocatalytic activities for the decomposition of Rhodamine B (RhB) under UV light irradiation.

scholarly journals The Potential for Natural Stones from Northeastern Brazil to Be Used in Civil Construction

Minerals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 440
Author(s):  
Fabiana Pereira da Costa ◽  
Jucielle Veras Fernandes ◽  
Luiz Ronaldo Lisboa de Melo ◽  
Alisson Mendes Rodrigues ◽  
Romualdo Rodrigues Menezes ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Thermal Analysis ◽  
Differential Thermal Analysis ◽  
Chemical Resistance ◽  
Mechanical Analysis ◽  
Northeastern Brazil ◽  
X Ray Diffraction ◽  
X Ray ◽  
Chemical Agents ◽  
Natural Stones

Natural stones (limestones, granites, and marble) from mines located in northeastern Brazil were investigated to discover their potential for use in civil construction. The natural stones were characterized by chemical analysis, X-ray diffraction, differential thermal analysis, and optical microscopy. The physical-mechanical properties (apparent density, porosity, water absorption, compressive and flexural strength, impact, and abrasion) and chemical resistance properties were also evaluated. The results of the physical-mechanical analysis indicated that the natural stones investigated have the potential to be used in different environments (interior, exterior), taking into account factors such as people’s circulation and exposure to chemical agents.

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