Specific heat behaviour of K2SeO4 in the 48K–800K temperature range a new phase transition

1980 ◽  
Vol 36 (12) ◽  
pp. 1021-1025 ◽  
Author(s):  
A. Lopez Echarri ◽  
M.J. Tello ◽  
P. Gili
Keyword(s):  
Phase Transition ◽  
Specific Heat ◽  
Temperature Range ◽  
New Phase

scholarly journals New Phase Transition Related to the Black Hole’s Topological Charge

2019 ◽  
Vol 2019 ◽  
pp. 1-8
Author(s):  
Shan-Quan Lan ◽  
Gu-Qiang Li ◽  
Jie-Xiong Mo ◽  
Xiao-Bao Xu
Keyword(s):  
Phase Transition ◽  
Specific Heat ◽  
Topological Charge ◽  
Energy Analysis ◽  
Van Der Waals ◽  
Tail Behavior ◽  
Maxwell Theory ◽  
Free Energy Analysis ◽  
Physical Quantities ◽  
New Phase

The topological charge ϵ of AdS black hole is introduced by Tian et al. in their papers, where a complete thermodynamic first law is obtained. In this paper, we investigate a new phase transition related to the topological charge in Einstein-Maxwell theory. Firstly, we derive the explicit solutions corresponding to the divergence of specific heat Cϵ and determine the phase transition critical point. Secondly, the T-r curve and T-S curve are investigated and they exhibit an interesting van der Waals system’s behavior. Critical physical quantities are also obtained which are consistent with those derived from the specific heat analysis. Thirdly, a van der Waals system’s swallow tail behavior is observed when ϵ>ϵc in the F-T graph. What is more, the analytic phase transition coexistence lines are obtained by using the Maxwell equal area law and free energy analysis, the results of which are consistent with each other.

SPECIFIC HEAT STUDY OF THE CDW PHASE TRANSITION IN THE DOPED BLUE BRONZES Tl0.3-xKxMoO3

2000 ◽  
Vol 14 (07n08) ◽  
pp. 251-258
Author(s):  
DINGLI WANG ◽  
JING SHI ◽  
XIAOKUI QIN ◽  
MINGLIANG TIAN ◽  
QINGMING XIAO ◽  
...  
Keyword(s):  
Phase Transition ◽  
Specific Heat ◽  
Second Order ◽  
One Dimensional ◽  
Temperature Range ◽  
Enthalpy Changes ◽  
Specific Heat Jump ◽  
Perfect Order ◽  
Blue Bronze

The specific heat of the doped blue bronzes Tl 0.3-x K x MoO 3 (x = 0.06, 0.15) has been measured in the temperature range between 100 and 220 K. Anomalies were observed at 165.7 K and 164.8 K for Tl 0.24 K 0.06 MoO 3 and Tl 0.15 K 0.15 MoO 3, respectively. The specific heat jump, and the entropy and enthalpy changes associated with the CDW phase transition are estimated. The results suggest that the Peierls phase transition is of second order. By analogy with the behavior of pure Tl 0.3-x MoO 3, it shows that in the quasi-one-dimensional blue bronze, the perfect order of the interlayer alkali or thallium polyhedral chain plays an important role in the Peierls phase transition.

SPECIFIC HEAT IN MONO-CRYSTAL YBCO: λ-LIKE ANOMALIES AT 90K AND 229K

1988 ◽  
Vol 02 (05) ◽  
pp. 1171-1183 ◽  
Author(s):  
K. Fossheim ◽  
O. M. Nes ◽  
T. Lægreid ◽  
C. N. W Darlington ◽  
D. A. O'Connor ◽  
...  
Keyword(s):  
Phase Transition ◽  
Specific Heat ◽  
High Precision ◽  
Order Phase Transition ◽  
Ybco Superconductor ◽  
Superconducting Transition ◽  
First Order ◽  
Temperature Range ◽  
First Order Phase Transition ◽  
First Order Phase

The specific heat, C p , has been measured with high precision in a mono-crystal of YBa 2 Cu 3 O 7−δ (YBCO) superconductor in the temperature range 55K-300K. The measurements provide data with a relative resolution Δ C p / C p of approximately 5 · 10−4. The main conclusions are: 1) Close to the superconducting transition the specific heat shows influence of fluctuations. 2) A reversible second order or weakly first order phase transition is found to occur at T o = 229 K .

INFLUENCE OF AN EXTERNAL MAGNETIC FIELD ON THE DYNAMICS OF A NEW-PHASE NUCLEUS IN THE VICINITY OF THE FIRST-ORDER PHASE TRANSITION IN MAGNETS WITH DEFECTS PRESENT

2012 ◽  
Vol 26 (28) ◽  
pp. 1250183 ◽  
Author(s):  
VLADIMIR NAZAROV ◽  
RISHAT SHAFEEV
Keyword(s):  
Magnetic Field ◽  
Phase Transition ◽  
External Magnetic Field ◽  
Magnetic Anisotropy ◽  
Spin Reorientation ◽  
Critical Fields ◽  
First Order ◽  
Phase Nucleus ◽  
First Order Phase Transition ◽  
New Phase

Theoretically, with the aid of a soliton model, the evolution of a new-phase nucleus near the first-order spin-reorientation phase transition in magnets has been investigated in an external magnetic field. The influence of an external field and one-dimensional defects of magnetic anisotropy on the dynamics of such nucleus has been demonstrated. The conditions for the localization of the new-phase nucleus in the region of the magnetic anisotropy defect and for its escape from the defect have been determined. The values of the critical fields which bring about the sample magnetization reversal have been identified and estimated.

Specific heat of Teflon-40 and BF-2 glue in the 10?300�K temperature range

1972 ◽  
Vol 22 (4) ◽  
pp. 450-451 ◽  
Author(s):  
V. S. Krylovskii ◽  
V. I. Ovcharenko ◽  
V. I. Khotkevich
Keyword(s):  
Specific Heat ◽  
Temperature Range

NQR and Crystal Structure of 4,5-Dichloroimidazole, C3H2N2Cl2

1992 ◽  
Vol 47 (1-2) ◽  
pp. 177-181 ◽  
Author(s):  
Shi-Qi Dou ◽  
Alarich Weiss
Keyword(s):  
Crystal Structure ◽  
Phase Transition ◽  
Temperature Dependence ◽  
Room Temperature ◽  
Unit Cell ◽  
Space Group ◽  
Temperature Range ◽  
Temperature Coefficients ◽  
Group D

AbstractThe two line 35Cl NQR spectrum of 4,5-dichloroimidazole was measured in the temperature range 77≦ T/K ≦ 389. The temperature dependence of the NQR frequencies conforms with the Bayer model and no phase transition is indicated in the curves v ( 35Cl)= f(T). Also the temperature coefficients of the 35Cl NQR frequencies are "normal". At 77 K the 35Cl NQR frequencies are 37.409 MHz and 36.172 MHz and at 389 K 35.758 MHz and 34.565 MHz. The compound crystallizes at room temperature with the tetragonal space group D44-P41212, Z = 8 molecules per unit cell; at 295 K : a = 684.2(5) pm, c = 2414.0(20) pm. The relations between the crystal structure and the NQR spectrum are discussed.

A new phase transition in NH4HSeO4 crystals

1981 ◽  
Vol 67 (2) ◽  
pp. K123-K125 ◽  
Author(s):  
J. Majszczyk ◽  
J. Rączka ◽  
Z. Czapla
Keyword(s):  
Phase Transition ◽  
New Phase
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