Ober Phaseniibergange von Ammonium-Alkali-Jodiden und verwandten Halogeniden / Phase Transitions of Ammonium-alkali Iodides and Related Halides

1981 ◽  
Vol 36 (3) ◽  
pp. 222-225 ◽  
Author(s):  
Peter Brauer
Keyword(s):  
Thermal Analysis ◽  
Differential Thermal Analysis ◽  
Phase Transitions ◽  
Martensitic Transition ◽  
Temperature Range

The investigation of the order-disorder transitions of the ammonium-chlorides and -bromides, in which some of the NH4+ are replaced by Cs+, Rb+ or K+, is extended to the corresponding iodides using birefringence and differential thermal analysis. As the temperature range of the martensitic transition (Pm 3 m↔Fm 3 m) is now overlapping the temperature range of the orderdisorder transitions, the former must be included in the measurements. The results allowing an overlook are discussed using the work of Garland, Lushington, and Leung [5]

Differential Thermal Analysis and Dielectric Studies on Neopentanol under Pressure

1992 ◽  
Vol 47 (11) ◽  
pp. 1127-1134 ◽  
Author(s):  
H. G. Kreul ◽  
R. Waldinger ◽  
A. Würflinger
Keyword(s):  
Thermal Analysis ◽  
Differential Thermal Analysis ◽  
Relaxation Time ◽  
Phase Transitions ◽  
Dielectric Relaxation ◽  
Pressure Dependence ◽  
Dielectric Relaxation Time ◽  
Dielectric Studies ◽  
Dielectric Measurements ◽  
Plastic Phase

Abstract Differential thermal analysis (DTA) and dielectric measurements have been performed on 2,2-dimethyl- 1-propanol (neopentanol) up to 200 MPa. Neopentanol exhibits at least one orientationally disordered (ODIC) phase (solid I) that transforms at lower temperatures to a non-plastic phase (solid II). There is evidence of a further ODIC phase denoted as solid I'. The pressure dependence of the phase transitions and the dielectric behaviour up to frequencies of 13 MHz are described. Activation enthalpies and volumes are derived from the dielectric relaxation time and compared with results for other alcohols

Behavior of thermal properties of AgCu1−xFexS compounds under non-isothermal conditions

2019 ◽  
Vol 33 (28) ◽  
pp. 1950339 ◽  
Author(s):  
Y. I. Aliyev ◽  
P. R. Khalilzade ◽  
Y. G. Asadov ◽  
T. M. Ilyasli ◽  
F. M. Mammadov ◽  
...  
Keyword(s):  
Phase Transition ◽  
Thermal Analysis ◽  
Differential Thermal Analysis ◽  
Thermal Properties ◽  
Phase Transitions ◽  
Structural Phase Transition ◽  
Structural Phase ◽  
Partial Replacement ◽  
Isothermal Conditions ◽  
The Given

AgCu[Formula: see text]Fe[Formula: see text]S compounds were synthesized by partial Cu[Formula: see text][Formula: see text][Formula: see text]Fe replacement in the AgCuS crystal at a concentration range of 0[Formula: see text][Formula: see text][Formula: see text]x[Formula: see text][Formula: see text][Formula: see text]0.03. In the differential thermal analysis spectrum obtained at a temperature range of 300 K[Formula: see text][Formula: see text][Formula: see text]T[Formula: see text][Formula: see text][Formula: see text]1300 K, endoeffect corresponding to the structural phase transition in the AgCuS compound was observed at the temperature T[Formula: see text]=[Formula: see text]938 K. It has been determined that this result is also observed in the AgCu[Formula: see text]Fe[Formula: see text]S compound obtained by partial replacement of Cu atoms by Fe atoms. However, in the compound of AgCu[Formula: see text]Fe[Formula: see text]S this effect was observed at higher temperatures. The thermal capacities and enthalpies of phase transitions were calculated for the given compounds.

New phase transitions in ceramic SrSnO3: Raman scattering analysis and differential thermal analysis

2008 ◽  
Vol 20 (5) ◽  
pp. 055210 ◽  
Author(s):  
Manoj K Singh ◽  
Naba K Karan ◽  
Ram S Katiyar ◽  
J F Scott ◽  
H M Jang
Keyword(s):  
Thermal Analysis ◽  
Differential Thermal Analysis ◽  
Phase Transitions ◽  
Raman Scattering ◽  
New Phase

APPLICATION OF DIFFERENTIAL THERMAL ANALYSIS TO THE DISSOCIATION OF MnO2 AND Mn2O3

1965 ◽  
Vol 43 (6) ◽  
pp. 1723-1728 ◽  
Author(s):  
T. Matsushima ◽  
W. J. Thoburn
Keyword(s):  
Thermal Analysis ◽  
Differential Thermal Analysis ◽  
Temperature Range ◽  
Heats Of Reaction

The method of differential thermal analysis was employed to determine the oxygen pressures produced by the reactions[Formula: see text]and[Formula: see text]in the temperature range 250–1000 °C. The heats of reaction calculated from the slope of the van't Hoff curves are: ΔH835°K0 = 25.8 ± 1.5 and ΔH1200°K0 = 25.3 ± 4.2 kcal per mole of oxygen. These are in agreement with previously reported values based on equilibrium measurements, but are lower than those determined by calorimetry.

scholarly journals Электрические взаимодействия в смесях сегнетоэлектрических порошков хлорида диизопропиламмония и титаната свинца

2021 ◽  
Vol 63 (6) ◽  
pp. 772
Author(s):  
С.В. Барышников ◽  
А.Ю. Милинский
Keyword(s):  
Thermal Analysis ◽  
Differential Thermal Analysis ◽  
Phase Transitions ◽  
Cooling Mode ◽  
Powder Mixtures ◽  
Heating And Cooling ◽  
Additional Phase

The results of studies of phase transitions in mixtures of C6H16NCl (DIPAC) powders with PbTiO3 by the method of differential thermal analysis (DTA) are pre-sented. The measurements were carried out in the heating and cooling mode in the tem-perature range from 300 to 440 K. It was found that electrical interactions between ferroelectric particles lead to the appearance of additional phase transitions for DIPAC in powder mixtures.

scholarly journals ROOT HARDINESS OF GRAPE CULTIVARS

HortScience ◽  
1990 ◽  
Vol 25 (9) ◽  
pp. 1136F-1136
Author(s):  
M. Ahmedullah ◽  
C. R. Rom
Keyword(s):  
Thermal Analysis ◽  
Differential Thermal Analysis ◽  
Free Water ◽  
Extracellular Water ◽  
Triphenyltetrazolium Chloride ◽  
Temperature Range ◽  
Survival Test ◽  
One Year ◽  
Grape Cultivars

Roots of one year old grape cvs. Concord, White Riesling, Grenache and Semillon were frozen to 0, -5, -10, -15 and -20°C in a programmable freezer. The tops were protected from cold by insulating them. For survival test, 4 plants of each cv. were planted in the greenhouse and their growth observed. Differential thermal analysis (DTA), using a computer attached to a programmable freezer was performed on roots. To aid in the interpretation of DTA, triphenyltetrazolium chloride (TTC) was performed. Hardiness determinations were based on DTA, TTC and the survival tests. DTA patterns representing exothermic response showed an exotherm associated with extracellular free water in tissue which appeared at about the same temperature range for all cvs. This is not associated with hardiness. Additional minor exotherms related to hardiness appeared at lower temperatures than the extracellular water exotherm. Their location differed from one cv. to another. Based on these tests, Concord roots appear to be hardier than other cvs. with important but minor differences in the hardiness of other cvs.

Phasendiagramme von (NH4, M)X und(ND4, M)X mit M = Tl, Rb oder Cs und X=Cl oder Br / Phase Diagrams of (NH4, M)X and (ND4, M)X with M = Tl, Rb or Cs and X = Cl or Br

1979 ◽  
Vol 34 (7) ◽  
pp. 862-866 ◽  
Author(s):  
Peter Brauer
Keyword(s):  
Thermal Analysis ◽  
Differential Thermal Analysis ◽  
Phase Transitions ◽  
Phase Diagrams ◽  
Isotope Effect ◽  
Lattice Constant ◽  
Negative Pressure ◽  
Phase Iii ◽  
Lattice Constants ◽  
Mixed Systems

Phase transitions in (NH4, M)Cl with M=Tl, Rb or Cs and (ND4, Tl)Cl as well as (NH4, M)Br and (ND4, M)Br are measured using birefringence or differential thermal analysis. The phase diagrams of the mixed systems with M=Tl having decreasing lattice constant with increasing amount of Tl are similar to the well known T(P) diagrams. Therefore the diagrams of the sys­tems with M=Rb or Cs having increasing lattice constants correspond to T(P) diagrams in the range of fictitious negative pressure P. Substitution of D for H produces an effect similar to reducing the lattice constant. The extraordinary large negative isotope effect of II-III transitions and the appearance of the birefringent phase III in the chlorides are now understood.

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