X-Ray, thermal, and Dehydration studies on Magnesium oxychlorides

1955 ◽  
Vol 8 (2) ◽  
pp. 234 ◽  
Author(s):  
WF Cole ◽  
T Demediuk
Keyword(s):  
Crystal Structure ◽  
Thermal Analysis ◽  
Differential Thermal Analysis ◽  
Atmospheric Conditions ◽  
X Ray ◽  
The Stability

X-ray, differential thermal analysis, and dehydration methods have been used to study the magnesium oxychlorides 3Mg(OH)2.MgCl2.8H2O and 5Mg(OH)2.MgCl2.8H2O formed at temperatures below 100 �C, and 2Mg(OH), . MgCl2.5H2O and 9Mg(OH)2.MgCl2.6H2O formed at temperatures at and above 100 'C. Lower hydrates of the 3-form exist with 5 and 4 molecules of water, results which differ from those of Feitknecht and Held (1944), Feitknecht (1953), and Wehner (1933). It 1s not clear from the new results whether the lower hydrates for the 5-form hare 5 and 3 or 4 and 3 molecules of water, but the latter seems the more likely ; the results of Feitknecht and Held suggested the former. For the 2- and 9-forms a lower hydrate with 2 molecules of water exists. In addition all forms have an anhydrous phase with the crystal structure of Mg(OH)2. The stability of all phases under natural atmospheric conditions is discussed.

scholarly journals Influence of the Al content on the phase transformations in Cu-Al-Ag alloys

2003 ◽  
Vol 28 (1) ◽  
pp. 33-38 ◽  
Author(s):  
A. T. Adorno ◽  
A. V. Benedetti ◽  
R. A. G. da Silva ◽  
M. Blanco
Keyword(s):  
Thermal Analysis ◽  
Differential Thermal Analysis ◽  
Transition Temperature ◽  
Phase Transformations ◽  
Decomposition Reaction ◽  
Phase Decomposition ◽  
Stability Range ◽  
X Ray ◽  
Al Content ◽  
The Stability

The influence of the Al content on the phase transformations in Cu-Al-Ag alloys was studied by classical differential thermal analysis (DTA), optical microscopy (OM) and X-ray diffractometry (XRD). The results indicated that the increase in the Al content and the presence of Ag decrease the rate of the <FONT FACE=Symbol>b</font>1 phase decomposition reaction and contribute for the raise of this transition temperature, thus decreasing the stability range of the perlitic phase resulted from the b1 decomposition reaction.

scholarly journals Preparation, differential thermal analysis and crystal structure of the new quaternary compound CuVInSe3

2018 ◽  
Vol 64 (6) ◽  
pp. 548
Author(s):  
Gustavo Marroquin ◽  
Gerzon E. Delgado ◽  
Pedro Grima-Gallardo ◽  
Miguel Quintero
Keyword(s):  
Crystal Structure ◽  
Thermal Analysis ◽  
Differential Thermal Analysis ◽  
Powder Diffraction ◽  
Powder Diffraction Data ◽  
Unit Cell Parameters ◽  
Quaternary Compound ◽  
X Ray ◽  
Cell Parameters ◽  
Structural Variables

The crystal structure of the quaternary compound CuVInSe3 belonging to the system (CuInSe2)1-x(VSe)x with x= ½, was analyzed using X-ray powder diffraction data. This material was synthesized by the melt and anneal method and crystallizes in the tetragonal space group P2c (Nº 112), with unit cell parameters a = 5.7909(4) Å, c = 11.625(1) Å, V = 389.84(5) Å3. The Rietveld refinement of 25 instrumental and structural variables led to Rexp = 6.6 %, Rp = 8.7 %, Rwp = 8.8 % and S = 1.3 for 4501 step intensities and 153 independent reflections. This compound has a normal adamantane structure and is isostructural with CuFeInSe3. The DTA indicates that this compound melts at 1332 K.

Crystal growth and structure analysis of Sm2−xCexCuO4

2000 ◽  
Vol 15 (9) ◽  
pp. 1905-1910 ◽  
Author(s):  
H. Takeda ◽  
M. Okuno ◽  
M. Ohgaki ◽  
K. Yamashita ◽  
T. Matsumoto
Keyword(s):  
Crystal Structure ◽  
Thermal Analysis ◽  
Phase Diagram ◽  
Differential Thermal Analysis ◽  
Floating Zone ◽  
X Ray Diffraction ◽  
Zone Method ◽  
Floating Zone Method ◽  
X Ray ◽  
Quench Method

The phase diagram of the Sm2O3–CuO system was investigated by the combination of the differential thermal analysis and the quench method. The results showed that Sm2CuO4 incongruently melts at about 1220 °C, and that the solid Sm2CuO4 exists in equilibrium with the liquid consisting of 81–95 mol% CuO in the range of 1060–1220 °C. On the basis of the phase diagram, Sm2−xCexCuO4 single crystals were grown by the traveling solvent floating zone method. The crystal structure [space group I4/mmm, a = 3.917(1), c 4 11.899(2) Å] has been refined using single-crystal x-ray diffraction data with a precision corresponding to an R index of 0.02.

Cyanoplatinate Halides – Synthesis, Crystal Structure Analyses and Vibrational Spectroscopy of Compounds A2[Pt(CN)4X2] (A = Rb, Cs; X = Cl, Br, I)

2010 ◽  
Vol 65 (9) ◽  
pp. 1066-1072 ◽  
Author(s):  
Claus Mühle ◽  
Jürgen Nuss ◽  
Robert E. Dinnebier ◽  
Martin Jansen
Keyword(s):  
Crystal Structure ◽  
Thermal Analysis ◽  
Raman Spectroscopy ◽  
Differential Thermal Analysis ◽  
Alkali Metal ◽  
X Ray ◽  
Infrared And Raman Spectroscopy ◽  
In Trans ◽  
Cyanide Ligands ◽  
Single Crystal Analysis

Crystal structures of the cyanoplatinates A2[Pt(CN)4X2] (A = Rb, Cs; X = Cl, Br, I) have been determined by single-crystal analysis and X-ray powder diffraction. The compounds were synthesized by metathesis from Ba[Pt(CN)4] ·4 H2O and alkali metal sulfates, and by subsequent oxidation with the respective halogens. The crystals were grown by slowly concentrating respective aqueous solutions. The PtIV cations are octahedrally coordinated by four cyanide ligands and two halogen atoms, the latter being located in trans positions. Rb2[Pt(CN)4Cl2]: triclinic, P¯1 (Z = 2), a = 6.7779(2), b = 9.3149(3), c = 9.6707(3) Å , α = 89.37(0), β = 76.05(0), γ = 72.98(0)◦, V = 565.42(2) Å3, N` hkl= 5616, R(F)N` = 0.0273; Rb2[Pt(CN)4I2]: monoclinic, P21/c (Z = 2), a = 7.4239(2), b = 9.2486(2), c = 9.1189(2) Å , β = 107.22(3)◦, V = 598.04(6) Å3, N` hkl = 2917, R(F)N` = 0.0295; Cs2[Pt(CN)4I2]: monoclinic, P21/c (Z = 2), a = 7.6740(4), b = 9.5397(5), c = 9.3474(5) Å , β = 106.46(0)◦, V = 656.3(2) Å3, Z = 2, N` hkl = 2738, R(F)N` = 0.0283; Cs2[Pt(CN)4Cl2]: monoclinic, C2/c (Z = 4), a = 17.947(4), b = 7.395(2), c = 12.031(3) Å , β = 131.904(1)◦, V = 1188.4(5) Å3, R-wp = 2.77; Cs2[Pt(CN)4Br2]: monoclinic, C2/c (Z = 4), a = 18.404(1), b = 7.2819(5), c = 12.4156(8) Å , β = 132.156(1)◦, V = 1233.5(1) Å3, N` hkl = 2566, R(F)N` = 0.0268. All compounds were characterized by differential thermal analysis, thermogravimetry, and infrared and Raman spectroscopy.

scholarly journals Fabrication of Aligned Side-by-Side TiO2/SnO2Nanofibers via Dual-Opposite-Spinneret Electrospinning

2012 ◽  
Vol 2012 ◽  
pp. 1-5 ◽  
Author(s):  
Fu Xu ◽  
Luming Li ◽  
Xiaojie Cui
Keyword(s):  
Crystal Structure ◽  
Thermal Analysis ◽  
Differential Thermal Analysis ◽  
Thermal Degradation ◽  
Anatase Phase ◽  
Electrospun Fibers ◽  
X Ray Diffraction ◽  
X Ray ◽  
Bicomponent Fibers ◽  
Photocatalytic Materials

Well-aligned and uniform side-by-side bicomponent fibers have been produced via dual-opposite-spinneret electrospinning. Side-by-side TiO2/SnO2nanofibers were obtained after calcining as-spun fibers. The thermal degradation of the electrospun fibers was evaluated using combined thermogravimetry and differential thermal analysis (TG-DTA), and the crystal structure of calcined nanofibers was investigated by X-ray diffraction (XRD). The fabricated TiO2/SnO2nanofibers expose both TiO2mainly consisting of anatase phase and rutile-type SnO2to the surface, which is appropriate for photocatalytic materials.

Research on the Structure of GdFeMn Compound

2017 ◽  
Vol 1142 ◽  
pp. 14-18 ◽  
Author(s):  
Shi Qian Zhao ◽  
Lei Ma ◽  
Liang Zhou ◽  
Tao Liu ◽  
Yong Bin Guo
Keyword(s):  
Crystal Structure ◽  
Electron Microscopy ◽  
Thermal Analysis ◽  
Solid Solution ◽  
Scanning Electron Microscopy ◽  
Differential Thermal Analysis ◽  
Rietveld Refinement ◽  
Single Phase ◽  
X Ray ◽  
Scanning Electron

The crystal structure of GdFeMn alloy has been investigated by using X-ray powder diffraction (XRD) followed by Rietveld refinement technique, differential thermal analysis (DTA) and scanning electron microscopy (SEM) equipped with energy dispersive X-ray spectroscopy (EDS) techniques. XRD results showed that annealed GdFeMn alloy was a single phase of Gd6(Fe0.5Mn0.5)23 compound, with Th6Mn23-structure. SEM/EDS results and Rietveld refinement revealed that GdFeMn alloy was not really a new ternary compound as reported, but a solid solution Gd6(Fe0.5Mn0.5)23 which was only a point between Gd6Fe23 and Gd6Mn23. It was also found from DTA measurement that a reaction, Gd (Fe0.5Mn0.5)2 → liquid (rich Gd) + Gd6(Fe0.5Mn0.5)23, had taken place above 650.81 oC, and the educed Gd existed in educed part of GdFeMn sample. The results demonstrated the real structure of the GdFeMn compound as reported was Gd6(Fe0.5Mn0.5)23 compound.

scholarly journals Synthesis and study of a novel 9P-type mixed layered tetradymite-like GeBi4Te4 compound in the Ge-Te-Bi system

2021 ◽  
Vol 22 (3) ◽  
pp. 401-406
Author(s):  
F.R. Aliyev
Keyword(s):  
Crystal Structure ◽  
Thermal Analysis ◽  
Differential Thermal Analysis ◽  
Phase Composition ◽  
Lattice Parameter ◽  
The Novel ◽  
Layered Chalcogenides ◽  
X Ray ◽  
Parameter Values ◽  
Scanning Electron

Taking as a base structural properties of the tetradymite-like layered chalcogenide compounds, a novel ternary GeBi4Te4 phase was predicted and synthesized. The polycrystal of this compound was synthesized and its single-crystal was grown by the vertical Brigman-Stokbarger method. The phase composition of obtained samples was analyzed by differential thermal analysis (DTA), X-ray powder diffraction (XRD), and scanning electron microscope (SEM). It was determined that the novel phase melts peritectially at 538 °C and has the following lattice parameter values in a hexagonal configuration: a=4,4071(6)Å, c=17,384(2)Å (sp. gr P3m1). This crystal structure is considered a derivative of tetradymite-like layered chalcogenides and consists of alternating Bi bilayers and GeBi2Te4 septuple packets.

A tetranuclear copper (II) complex with pyrazole-3,5-dicarboxylate ligands: synthesis, characterization and electrochemical properties

2016 ◽  
Vol 71 (4) ◽  
pp. 305-310 ◽  
Author(s):  
Selçuk Demir ◽  
Hamide Merve Çepni ◽  
Małgorzata Hołyńska ◽  
Muammer Kavanoz
Keyword(s):  
Crystal Structure ◽  
Thermal Analysis ◽  
Differential Thermal Analysis ◽  
Hydrogen Bonds ◽  
Room Temperature ◽  
Magnetic Measurements ◽  
Metal Oxidation ◽  
X Ray Diffraction ◽  
X Ray ◽  
Complex Anions

AbstractA tetranuclear copper (II) complex with pyrazole-3,5-dicarboxylate ligands (pdc3−), [Me2NH2]4[Cu4(pdc)4], was synthesized using solvothermal and metal oxidation routes and characterized by elemental analysis, infrared, thermogravimetry/differential thermal analysis, and room-temperature magnetic measurements. The structure of the complex was determined by single-crystal X-ray diffraction. It comprises dimethylammonium cations and complex anions containing four Cu2+ cations. The crystal structure is stabilized by N–H···O hydrogen bonds. In addition, the electrochemical behavior was studied.

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.

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.

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