Unprecedented transformation of [I−·I3−] to [I42−] polyiodides in the solid state: structures, phase transitions and characterization of dipyrazolium iodide triiodide

2015 ◽  
Vol 44 (42) ◽  
pp. 18447-18458 ◽  
Author(s):  
M. Węcławik ◽  
P. Szklarz ◽  
W. Medycki ◽  
R. Janicki ◽  
A. Piecha-Bisiorek ◽  
...  

Dipyrazolium iodide triiodide, [C3N2H5+]2[I−·I3−], has been synthesized and studied by means of X-ray diffraction, differential scanning calorimetry, dielectric measurements, and UV-Vis spectroscopy.

2010 ◽  
Vol 62 ◽  
pp. 101-106 ◽  
Author(s):  
Djahida Talantikite-Touati ◽  
Laldja Benzïada

Oxyfluoride phases have been synthesized in free atmosphere, using the initially synthesized perovskite BaTiO3 and the fluorides NaF and MgF2. The purity of BaTiO3 and oxyfluorides has been checked by X–Ray diffraction (XRD).The microstructures of these phases are observed by scanning electron microscopy. The phase transitions have been investigated by dielectric measurements and differential scanning calorimetry (DSC).


2010 ◽  
Vol 24 (09) ◽  
pp. 1137-1140 ◽  
Author(s):  
M. M. VERDIAN ◽  
M. SALEHI ◽  
K. RAEISSI

Amorphous/nanocrystalline 50 Ni –50 Ti powders were synthesized from elemental Ti and Ni powders by solid state synthesis utilizing low energy mechanical alloying with times up to 100 h. The produced powders were investigated by X-ray diffraction and differential scanning calorimetry to study phase transformations that occurred during heating in the calorimeter. It was found that at the first stage of the heating process, a disordered NiTi phase was formed at temperature of about 400°C. Further investigations indicated that this phase transformed into the Ni 3 Ti and Ti 2 Ni intermetallic compounds after heating at a temperature of about 800°C.


1988 ◽  
Vol 123 ◽  
Author(s):  
J. E. Smeaton ◽  
George Burns

AbstractThe Tomb of Nefertari, no. 66, Valley of the Queens, is an internationally known monument of historic and artistic importance; it is considere d one of the most beautiful of the Royal Egyptian tombs. The fragility of its plaster along with its ubiquitous sodium chloride crystals and microcrystals have complicated its conservation and restoration. In order to determine the optimum pathway for its conservation, the physicochemical processes which occur now in this Tomb must be well understood. To improve this understanding, samples of plaster taken from the Tomb have been analyzed using Differential Scanning Calorimetry and X-ray Diffraction and have been shown to be fully dehydrated; previous findings suggest that this is not the case in all contemporary Royal tombs. Although we are not aware of any kinetic study of gypsum dehydration in the solid state, the presence of anhydrite in the Tomb of Nefertari suggests that the CaSO4 ·2H2O → CaSO4 + 2H2O reaction is catalyzed. It is reasoned that finely-dispersed sodium chloride crystals act as effective catalysts in this reaction.


2021 ◽  
Vol 2129 (1) ◽  
pp. 012092
Author(s):  
Suffi Irni Alias ◽  
Banjuraizah Johar ◽  
Syed Nuzul Fadzli Adam ◽  
Mustaffa Ali Azhar Taib ◽  
Fatin Fatini Othman ◽  
...  

Abstract The porcelain formulation containing percentages of treated FGD sludge waste from 5% up to 15% in replacement of feldspar were prepared. The porcelain mixture formulation were mixed by high energy planatery mill at speed 300 rpm for 1 hours. The powder were compacted by using hydraulic press and sintered at temperature 1200 °C for 3 hours. The sintered samples were characterized using X-ray fluorescene (XRF), X-ray diffraction (XRD), Fourier Transform Infrared (FTIR) and Thermogravimetry/Differential scanning calorimetry (TGA/DCS). The primary effect concerning the addition of treated FGD sludge was the change of intensity composition (gypsum and anhydrate) in porcelain formulation. The XRD analysis has shown that the main component in sludge waste were gypsum and anhydrate.


1998 ◽  
Vol 23 (0) ◽  
pp. 91-98 ◽  
Author(s):  
Ana Glauce ZAINA CHIARETTO ◽  
Marco Aurélio da Silva CARVALHO FILHO ◽  
Nedja Suely FERNANDES ◽  
Massao IONASHIRO

Solid state compounds of general formula ML2.nH2O [where M is Mg, Ca, Sr or Ba; L is cinnamate (C6H5 -CH=CH-COO-) and n = 2, 4, 0.8, 3 respectively], have been synthetized. Thermogravimetry (TG), derivative thermogravimetry (DTG), differential scanning calorimetry (DSC) and X-ray diffraction powder patterns have been used to characterize and to study the thermal stability and thermal decomposition of these compounds.


2007 ◽  
Vol 72 (12) ◽  
pp. 1281-1293 ◽  
Author(s):  
Vukadin Leovac ◽  
Zoran Tomic ◽  
Katalin Mészáros-Szécsényi ◽  
Ljiljana Jovanovic ◽  
Milan Joksovic

The crystal and molecular structures of four tetrahedral structurally similar [Co(aamp)2X2] complexes (aamp = 4-acetyl-3-amino-5-methylpyrazole, X = Cl, Br, I and NCS) were determined by X-ray diffraction analysis and are discussed in detail. It was found that the different capacity of the ligand X (NCS vs. Cl, Br, I) for the formation of non-bonding contacts influence the mode of molecular association in the solid state. The complexes were characterized by UV-Vis spectroscopy. The first step of the thermal decomposition of the compounds was checked and is discussed in the view of the IR spectrum of the intermediate isolated from [Co(aamp)2Br2] by the quasi-isothermal technique.


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