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Journal articles on the topic 'Phase transitions'

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Author: Grafiati

Published: 4 June 2021

Last updated: 25 May 2024

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1

Tang, Xiaochu, and Yuan Li. "Phase division and transition modeling based on the dominant phase identification for multiphase batch process quality prediction." Transactions of the Institute of Measurement and Control 42, no. 5 (November 4, 2019): 1022–36. http://dx.doi.org/10.1177/0142331219881343.

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Batch processes are carried out from one steady phase to another one, which may have multiphase and transitions. Modeling in transitions besides in the steady phases should also be taken into consideration for quality prediction. In this paper, a quality prediction strategy is proposed for multiphase batch processes. First, a new repeatability factor is introduced to divide batch process into different steady phases and transitions. Then, the different local cumulative models that considered the cumulative effect of process variables on quality are established for steady phases and transitions. Compared with the reported modeling methods in transitions, a novel just-in-time model can be established based on the dominant phase identification. The proposed method can not only consider the dynamic characteristic in the transition but also improve the accuracy and the efficiency of transitional models. Finally, online quality prediction is performed by accumulating the prediction results from different phases and transitions. The effectiveness of the proposed method is demonstrated by penicillin fermentation process.

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2

KIM, SANG PYO. "DYNAMICAL THEORY OF PHASE TRANSITIONS AND COSMOLOGICAL EW AND QCD PHASE TRANSITIONS." Modern Physics Letters A 23, no. 17n20 (June 28, 2008): 1325–35. http://dx.doi.org/10.1142/s0217732308027692.

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We critically review the cosmological EW and QCD phase transitions. The EW and QCD phase transitions would have proceeded dynamically since the expansion of the universe determines the quench rate and critical behaviors at the onset of phase transition slow down the phase transition. We introduce a real-time quench model for dynamical phase transitions and describe the evolution using a canonical real-time formalism. We find the correlation function, the correlation length and time and then discuss the cosmological implications of dynamical phase transitions on EW and QCD phase transitions in the early universe.

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3

Weidemann, Sebastian, Mark Kremer, Stefano Longhi, and Alexander Szameit. "Topological triple phase transition in non-Hermitian Floquet quasicrystals." Nature 601, no. 7893 (January 19, 2022): 354–59. http://dx.doi.org/10.1038/s41586-021-04253-0.

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AbstractPhase transitions connect different states of matter and are often concomitant with the spontaneous breaking of symmetries. An important category of phase transitions is mobility transitions, among which is the well known Anderson localization1, where increasing the randomness induces a metal–insulator transition. The introduction of topology in condensed-matter physics2–4 lead to the discovery of topological phase transitions and materials as topological insulators5. Phase transitions in the symmetry of non-Hermitian systems describe the transition to on-average conserved energy6 and new topological phases7–9. Bulk conductivity, topology and non-Hermitian symmetry breaking seemingly emerge from different physics and, thus, may appear as separable phenomena. However, in non-Hermitian quasicrystals, such transitions can be mutually interlinked by forming a triple phase transition10. Here we report the experimental observation of a triple phase transition, where changing a single parameter simultaneously gives rise to a localization (metal–insulator), a topological and parity–time symmetry-breaking (energy) phase transition. The physics is manifested in a temporally driven (Floquet) dissipative quasicrystal. We implement our ideas via photonic quantum walks in coupled optical fibre loops11. Our study highlights the intertwinement of topology, symmetry breaking and mobility phase transitions in non-Hermitian quasicrystalline synthetic matter. Our results may be applied in phase-change devices, in which the bulk and edge transport and the energy or particle exchange with the environment can be predicted and controlled.

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4

Scott, Adam D., Dawn M. King, Stephen W. Ordway, and Sonya Bahar. "Phase transitions in evolutionary dynamics." Chaos: An Interdisciplinary Journal of Nonlinear Science 32, no. 12 (December 2022): 122101. http://dx.doi.org/10.1063/5.0124274.

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Sharp changes in state, such as transitions from survival to extinction, are hallmarks of evolutionary dynamics in biological systems. These transitions can be explored using the techniques of statistical physics and the physics of nonlinear and complex systems. For example, a survival-to-extinction transition can be characterized as a non-equilibrium phase transition to an absorbing state. Here, we review the literature on phase transitions in evolutionary dynamics. We discuss directed percolation transitions in cellular automata and evolutionary models, and models that diverge from the directed percolation universality class. We explore in detail an example of an absorbing phase transition in an agent-based model of evolutionary dynamics, including previously unpublished data demonstrating similarity to, but also divergence from, directed percolation, as well as evidence for phase transition behavior at multiple levels of the model system's evolutionary structure. We discuss phase transition models of the error catastrophe in RNA virus dynamics and phase transition models for transition from chemistry to biochemistry, i.e., the origin of life. We conclude with a review of phase transition dynamics in models of natural selection, discuss the possible role of phase transitions in unraveling fundamental unresolved questions regarding multilevel selection and the major evolutionary transitions, and assess the future outlook for phase transitions in the investigation of evolutionary dynamics.

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5

ZHU, SHI-LIANG. "GEOMETRIC PHASES AND QUANTUM PHASE TRANSITIONS." International Journal of Modern Physics B 22, no. 06 (March 10, 2008): 561–81. http://dx.doi.org/10.1142/s0217979208038855.

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Quantum phase transition is one of the main interests in the field of condensed matter physics, while geometric phase is a fundamental concept and has attracted considerable interest in the field of quantum mechanics. However, no relevant relation was recognized before recent work. In this paper, we present a review of the connection recently established between these two interesting fields: investigations in the geometric phase of the many-body systems have revealed the so-called "criticality of geometric phase", in which the geometric phase associated with the many-body ground state exhibits universality, or scaling behavior in the vicinity of the critical point. In addition, we address the recent advances on the connection of some other geometric quantities and quantum phase transitions. The closed relation recently recognized between quantum phase transitions and some of the geometric quantities may open attractive avenues and fruitful dialogue between different scientific communities.

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6

SOLLER, H., and D. BREYEL. "SIGNATURES IN THE CONDUCTANCE FOR PHASE TRANSITIONS IN EXCITONIC SYSTEMS." Modern Physics Letters B 27, no. 25 (September 23, 2013): 1350185. http://dx.doi.org/10.1142/s0217984913501856.

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In this paper, we analyze two phase transitions in exciton bilayer systems: a topological phase transition to a phase which hosts Majorana fermions and a phase transition to a Wigner crystal. Using generic simple models for different phases, we discuss the conductance properties of the latter when contacted to metallic leads and demonstrate the possibility to observe the different phase transitions by simple conductance measurements.

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7

Hu, Xi Duo, De Hai Zhu, Zhi Feng Zeng, and Shao Rui Sun. "The Theoretical Study of the Cinnabar-to-Rocksalt Phase Transitions of HgTe and CdTe under High Pressure." Advanced Materials Research 1004-1005 (August 2014): 1608–14. http://dx.doi.org/10.4028/www.scientific.net/amr.1004-1005.1608.

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We performed the first-principle calculation to study the structures of cinnabar phase and the Cinnabar-to-rocksalt Phase transitions of HgTe and CdTe under high pressure. The calculated results show that for HgTe, the zincblende-to-cinnabar phase transition is under 2.2GPa, and the cinnabar-to-rocksalt phase transition is under 5.5 GPa; For CdTe, the two phase transitions occur under 4.0 GPa and 4.9 GPa, respectively, which well agree with the experimental results. The cinnabar-to-rocksalt phase transitions of most compounds, including HgTe and CdTe, except HgS are of first-order, and it is due to that their cinnabar phases are not chain structure as HgS and there are no relaxation process before the phase transition.

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8

Wheeler, John F., Thomas L. Beck, S. J. Klatte, Lynn A. Cole, and John G. Dorsey. "Phase transitions of reversed-phase stationary phases." Journal of Chromatography A 656, no. 1-2 (December 1993): 317–33. http://dx.doi.org/10.1016/0021-9673(93)80807-k.

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9

Matsuyama, Akihiko. "Volume Phase Transitions of Heliconical Cholesteric Gels under an External Field along the Helix Axis." Gels 6, no. 4 (November 16, 2020): 40. http://dx.doi.org/10.3390/gels6040040.

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We present a mean field theory to describe cholesteric elastomers and gels under an external field, such as an electric or a magnetic field, along the helix axis of a cholesteric phase. We study the deformations and volume phase transitions of cholesteric gels as a function of the external field and temperature. Our theory predicts the phase transitions between isotropic (I), nematic (N), and heliconical cholesteric (ChH) phases and the deformations of the elastomers at these phase transition temperatures. We also find volume phase transitions at the I−ChH and the N−ChH phase transitions.

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10

Paroli, Ralph M., Nancy T. Kawai, Ian S. Butler, and Denis F. R. Gilson. "Phase transitions in adamantane derivatives: 2-chloroadamantane." Canadian Journal of Chemistry 66, no. 8 (August 1, 1988): 1973–78. http://dx.doi.org/10.1139/v88-318.

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The phase transition behaviour of 2-chloroadamantane, 2-C10H15Cl, has been investigated by differential scanning calorimetry (DSC), and FT-IR and Raman spectroscopy. Two transitions were detected by both DSC and vibrational spectroscopy at 231 and 178 K, on cooling, and at 242 and 227 K, on heating. The measured enthalpies were 8.3 kJ mol−1 for the first transition (phase I → phase II), and 0.47 kJ mol−1 for the second (phase II → phase III). The entropies were 35 and 2.3 J K−1 mol−1, respectively. These are similar to those observed for other 2-substituted adamantanes, but significantly different from those for 1-substituted derivatives. The large hystereses observed for the two transitions are independent of the DSC scanning rate and are characteristic of first-order phase transitions. The dramatic differences observed in the vibrational spectra of phases I and II provide clear evidence of an order–disorder transition at about 235 K.

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11

Suhara, Masahiko, and Koichi Mano. "NQR and Phase Transitions in Hexachlorocyclopropane Crystal." Zeitschrift für Naturforschung A 45, no. 3-4 (April 1, 1990): 339–42. http://dx.doi.org/10.1515/zna-1990-3-421.

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Abstract35Cl NQR and DSC studies on phase transitions in hexachlorocyclopropane (HCCP), C3Cl6 , are reported. It is found that HCCP has three solid phases: A high temperature disordered phase (Phase I) above 301 K (no NQR spectrum was observed); a metastable phase (Phase II), which exhibited 6 NQR lines from 77 to 270 K; a low temperature phase (Phase III) in which a 24-multiplet of 35Cl NQR lines at 77 K, the most complex multiplet spectrum ever reported was observed. DSC measurement shows a A-type transition at 301 K and a broad transition of very slow rate at 285 K. The structure and mechanism of phase transitions in HCCP crystal are discussed.

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12

Nechaev, V. N., and A. V. Shuba. "The size effects on phase transitions in ferroics." Известия Российской академии наук. Серия физическая 87, no. 9 (September 1, 2023): 1229–36. http://dx.doi.org/10.31857/s0367676523702174.

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The features of phase transitions temperature behavior in nanosized ferroics are discussed in the framework of phenomenological theories. It is shown that in the case of second-order transitions to both the commensurate and incommensurate phases, the critical temperature can shift significantly depending on the characteristic dimensions of the sample and the properties of the surface. In materials with the first-order phase transition, size effects have a significant influence on the nucleation process, leading to the transition temperature shift or even the phase transition type change have been determined.

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13

Carpenter, Michael. "Phase transitions in minerals: strain and elasticity." European Journal of Mineralogy 10, no. 4 (July 10, 1998): 619–20. http://dx.doi.org/10.1127/ejm/10/4/0619.

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14

Cellai, Daniela, Michael A. Carpenter, and Peter J. Heaney. "Phase transitions and microstructures in natural kaliophilite." European Journal of Mineralogy 4, no. 6 (December 15, 1992): 1209–20. http://dx.doi.org/10.1127/ejm/4/6/1209.

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15

Dombal, Richard F. De, and Michael A. Carpenter. "High-temperature phase transitions in Steinbach tridymite." European Journal of Mineralogy 5, no. 4 (July 22, 1993): 607–22. http://dx.doi.org/10.1127/ejm/5/4/0607.

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16

Martín-Olalla, José María, Stuart A. Hayward, Hinrich-Wilhelm Meyer, Saturio Ramos, Jaime Del Cerro, and Michael A. Carpenter. "Phase transitions in lawsonite: a calorimetric study." European Journal of Mineralogy 13, no. 1 (January 31, 2001): 5–14. http://dx.doi.org/10.1127/0935-1221/01/0013-0005.

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17

Kubicki, Maciej. "Structural Aspects of Phase Transitions." Solid State Phenomena 112 (May 2006): 1–20. http://dx.doi.org/10.4028/www.scientific.net/ssp.112.1.

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There are two kinds of structural transformations in the crystalline solid state: solid state reactions, in which the product chemically different from the starting material can be isolated, and polymorphic transitions, when the phases have different organization of identical molecules in the crystal structures. As a consequence, the starting and the final phases of a solid state reaction differ in the melt and vapor, while different polymorphic modifications are identical in melt or gas phase. Some examples of the different phase transitions in the solid state are described in detail: the π-molecular complexes, the hydrogen-bond transformations and the reversible single crystal - twin transition.

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18

Sierant, Piotr, Giuliano Chiriacò, Federica M. Surace, Shraddha Sharma, Xhek Turkeshi, Marcello Dalmonte, Rosario Fazio, and Guido Pagano. "Dissipative Floquet Dynamics: from Steady State to Measurement Induced Criticality in Trapped-ion Chains." Quantum 6 (February 2, 2022): 638. http://dx.doi.org/10.22331/q-2022-02-02-638.

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Quantum systems evolving unitarily and subject to quantum measurements exhibit various types of non-equilibrium phase transitions, arising from the competition between unitary evolution and measurements. Dissipative phase transitions in steady states of time-independent Liouvillians and measurement induced phase transitions at the level of quantum trajectories are two primary examples of such transitions. Investigating a many-body spin system subject to periodic resetting measurements, we argue that many-body dissipative Floquet dynamics provides a natural framework to analyze both types of transitions. We show that a dissipative phase transition between a ferromagnetic ordered phase and a paramagnetic disordered phase emerges for long-range systems as a function of measurement probabilities. A measurement induced transition of the entanglement entropy between volume law scaling and sub-volume law scaling is also present, and is distinct from the ordering transition. The two phases correspond to an error-correcting and a quantum-Zeno regimes, respectively. The ferromagnetic phase is lost for short range interactions, while the volume law phase of the entanglement is enhanced. An analysis of multifractal properties of wave function in Hilbert space provides a common perspective on both types of transitions in the system. Our findings are immediately relevant to trapped ion experiments, for which we detail a blueprint proposal based on currently available platforms.

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19

Kuryleva, Yulia N., Olga A. Chalaya, and D. A. Zakharyevich. "Phase Transitions in Perovskite Phases of Strontium Silicoantimonates." Materials Science Forum 845 (March 2016): 34–37. http://dx.doi.org/10.4028/www.scientific.net/msf.845.34.

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The paper presents the results of the study of phase transitions in the system Sr-Sb-Si-O by means of X-ray diffraction, thermal analysis, dielectric spectroscopy. Four effects are observed in the interval from room temperature to 800°C. The first and last are chemical transformations due to dehydration and loss of oxygen, respectively. The second is a transition from tetragonal to cubic perovskite structure, and the third is disordering transition in oxygen sublattice possibly due to the desorption of structural water molecules

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20

Haines, Julian, and D. F. R. Gilson. "Phase transitions in solid cycloheptene." Canadian Journal of Chemistry 68, no. 4 (April 1, 1990): 604–11. http://dx.doi.org/10.1139/v90-093.

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The phase transition behaviour of cycloheptene has been investigated by differential scanning calorimetry, proton spin-lattice relaxation, and vibrational spectroscopy (infrared and Raman). Two solid–solid phase transitions were observed, at 154 and 210 K, with transition enthalpies and entropies of 5.28 and 0.71 kJ mol−1 and 34.3 and 3.4 JK−1, respectively. Cycloheptene melted at 217 K with an entropy of melting of 4.5 JK−1 mol−1. The bands in the vibrational spectra of the two high temperature phases were broad and featureless, characteristic of highly disordered phases. The presence of other conformers, in addition to the chair form, was indicated from bands in the spectra. The ring inversion mode was highly phase dependent and exhibited soft mode type behaviour prior to the transition from the low temperature phase. The low frequency Raman spectra (external modes) of these phases indicated that the molecules are undergoing isotropic reorientation. In the low temperature phase, the vibrational bands were narrow; the splitting of the fundamentals into two components and the presence of nine external modes are consistent with unit cell symmetry of either C2 or Cs with two molecules per primitive unit cell. A glassy state can be produced from the intermediate phase and the vibrational spectra were very similar to those of the high temperature phases, indicating that static disorder was present. The barriers to reorientation, as obtained from proton spin-lattice relaxation measurements, are 9.0 kJ mol−1 in both the high temperature phases, and 15.4 kJ mol−1 in the low temperature, ordered phase. Keywords: cycloheptene, phase transition, differential scanning calorimetry, NMR, vibrational spectroscopy.

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21

Shevchenko, O., A. Sokolenko, I. Maksymenko, and K. Vasylkivsky. "Phase transitions." Scientific Works of National University of Food Technologies 27, no. 2 (April 2021): 100–110. http://dx.doi.org/10.24263/2225-2924-2021-27-2-12.

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22

PETER, Thomas, and Thomas KOOP. "PHASE TRANSITIONS." Journal of Aerosol Science 32 (September 2001): 9–10. http://dx.doi.org/10.1016/s0021-8502(21)00014-8.

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23

Allen, Dick. "Phase Transitions." Chicago Review 40, no. 2/3 (1994): 115. http://dx.doi.org/10.2307/25305858.

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24

Lawrie, I. D. "Phase transitions." Contemporary Physics 28, no. 6 (November 1987): 599–601. http://dx.doi.org/10.1080/00107518708213745.

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25

Liebau, F. "Phase transitions." Journal of Thermal Analysis 33, no. 1 (March 1988): 107–11. http://dx.doi.org/10.1007/bf01914589.

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26

TERAOKA, Y. "PHASE TRANSITIONS ON ALLOY SURFACES." Surface Review and Letters 03, no. 05n06 (October 1996): 1791–809. http://dx.doi.org/10.1142/s0218625x96002734.

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Various kinds of quasi-two-dimensional order-disorder phase transitions on binary alloy surfaces are discussed on the basis of the lattice gas model with appropriate approximations. The importance of surface segregation is pointed out in understanding phase transitions on alloy surfaces. Ordered structures localized on the surfaces are found above the bulk transition temperature, and a possibility of finding surface ordered structures with a different symmetry from the bulk ordered one is discussed, too. As for both ordering and segregating alloys, semi-infinite systems with surfaces are discussed above and below the bulk transition temperatures; in particular, the relation of the surface phase transitions to the bulk ones is focused on.

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27

Nguyen, Thi Phuong Thuy, Thi Van Anh Nguyen, and Van Thanh Ngo. "Phase transitions of smectic-isotropic phase in liquid crystals." Ministry of Science and Technology, Vietnam 66, no. 1 (January 15, 2024): 1–7. http://dx.doi.org/10.31276/vjst.66(1).01-07.

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Smectic phases formed by rod-like molecules with long axes that are parallel and also arranged in planes. The smectic-isotropic phase transition is a phase change from the liquid crystal to the liquid phase. In this work, we use a mobile 6-state Potts model to study the nature of the smectic-isotropic phase transition. Microscopic interactions between neighbouring molecules in this model are supplemented with the Lennard-Jones potential. This study applies Monte Carlo simulation with the Wang-Landau algorithm to determine the characteristics of smectic-isotropic phase transitions. It is shown clearly that the smectic phase goes to the isotropic phase and undergoes a first-order transition. The results also point out that when the temperature increases, molecules on the surface are orientationally disordered, then the molecules gradually lose their positional order. These results are in agreement with experiments that revealed the coexistence of the smectic and isotropic phasesduring the phase transition process in accordance with experimental studies.

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28

Werheit, Helmut. "Phase Transitions in Boron Carbide." Materials 16, no. 20 (October 17, 2023): 6734. http://dx.doi.org/10.3390/ma16206734.

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The idealized rhombohedral unit cell of boron carbide is formed by a 12-atom icosahedron and a 3-atom linear chain. Phase transitions are second order and caused by the exchange of B and C sites or by vacancies in the structure. Nevertheless, the impact of such minimal structural changes on the properties can be significant. As the X-ray scattering cross sections of B and C isotopes are very similar, the capability of X-ray fine structure investigation is substantially restricted. Phonon spectroscopy helps close this gap as the frequency and strength of phonons sensitively depend on the bonding force and mass of the vibrating atoms concerned. Phase transitions known to date have been identified due to significant changes of properties: (1) The phase transition near the chemical composition B8C by clear change of the electronic structure; (2) the endothermic temperature-dependent phase transition at 712 K according to the change of specific heat; (3) the high-pressure phase transition at 33.2 GPa by the drastic change of optical appearance from opacity to transparency. These phase transitions affect IR- and Raman-active phonons and other solid-state properties. The phase transitions at B~8C and 712 K mean that a well-defined distorted structure is converted into another one. In the high-pressure phase transition, an apparently well-defined distorted structure changes into a highly ordered one. In all these cases, the distribution of polar C atoms in the icosahedra plays a crucial role.

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29

ALBEVERIO, SERGIO, YURI KONDRATIEV, YURI KOZITSKY, and MICHAEL RÖCKNER. "PHASE TRANSITIONS AND QUANTUM EFFECTS IN ANHARMONIC CRYSTALS." International Journal of Modern Physics B 26, no. 11 (April 30, 2012): 1250063. http://dx.doi.org/10.1142/s0217979212500634.

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The most important recent results in the theory of phase transitions and quantum effects in quantum anharmonic crystals are presented and discussed. In particular, necessary and sufficient conditions for a phase transition to occur at some temperature are given in the form of simple inequalities involving the interaction strength and the parameters describing a single oscillator. The main characteristic feature of the theory is that both mentioned phenomena are described in one and the same setting, in which thermodynamic phases of the model appear as probability measures on path spaces. Then the possibility of a phase transition to occur is related to the existence of multiple phases at the same values of the relevant parameters. Other definitions of phase transitions, based on the nondifferentiability of the free energy density and on the appearance of ordering, are also discussed.

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30

Zhang, Xinyu, Lidong Dai, Haiying Hu, and Chuang Li. "Pressure-Induced Reverse Structural Transition of Calcite at Temperatures up to 873 K and Pressures up to 19.7 GPa." Minerals 13, no. 2 (January 27, 2023): 188. http://dx.doi.org/10.3390/min13020188.

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In situ Raman scattering and electrical conductivity experiments have been performed to investigate the structural phase transitions of calcite during the compressed and decompressed processes in a diamond anvil cell at temperatures of 298–873 K and pressures up to 19.7 GPa. Upon compression, calcite (CaCO3-I phase) underwent three structural phase transitions from CaCO3-I to CaCO3-II phases at 1.6 GPa, from CaCO3-II to CaCO3-III phases at 2.2 GPa, and from CaCO3-III to CaCO3-VI phases at 16.8 GPa under room temperature conditions, which were evidenced by the evolution of Raman peaks, as well as the discontinuities in the pressure-dependent Raman shifts and electrical conductivity. Upon decompression, the structural phase transitions from CaCO3-VI to CaCO3-III to CaCO3-II to CaCO3-I phases took place at the respective pressures of 5.4, 1.5, and 0.4 GPa, indicating the reversibility of calcite. Furthermore, an obvious ~11 GPa of pressure hysteresis was detected in the CaCO3-VI to CaCO3-III phase transition, whereas other reverse phase transition pressures were very close to those of compressed results. At three given representative pressure conditions (i.e., 10.5, 12.5, and 13.8 GPa), a series of electrical conductivity experiments were performed at temperature ranges of 323–873 K to explore the temperature-dependent relation of CaCO3-III to CaCO3-VI structural phase transition. With increasing pressure, the transition temperature between CaCO3-III and CaCO3-VI phases gradually decreases, which reveals an obviously negative temperature-pressure relation, i.e., P (GPa) = 19.219 (±1.105) − 0.011 (±0.002) T (K). Our acquired phase diagram of calcite can be employed to understand the high-pressure structural transitions and phase stability for carbonate minerals along various subducting slabs in the deep Earth’s interior.

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31

Seddon, John M., Adam M. Squires, Charlotte E. Conn, Oscar Ces, Andrew J. Heron, Xavier Mulet, Gemma C. Shearman, and Richard H. Templer. "Pressure-jump X-ray studies of liquid crystal transitions in lipids." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 364, no. 1847 (August 21, 2006): 2635–55. http://dx.doi.org/10.1098/rsta.2006.1844.

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In this paper, we give an overview of our studies by static and time-resolved X-ray diffraction of inverse cubic phases and phase transitions in lipids. In §1 , we briefly discuss the lyotropic phase behaviour of lipids, focusing attention on non-lamellar structures, and their geometric/topological relationship to fusion processes in lipid membranes. Possible pathways for transitions between different cubic phases are also outlined. In §2 , we discuss the effects of hydrostatic pressure on lipid membranes and lipid phase transitions, and describe how the parameters required to predict the pressure dependence of lipid phase transition temperatures can be conveniently measured. We review some earlier results of inverse bicontinuous cubic phases from our laboratory, showing effects such as pressure-induced formation and swelling. In §3 , we describe the technique of pressure-jump synchrotron X-ray diffraction. We present results that have been obtained from the lipid system 1 : 2 dilauroylphosphatidylcholine/lauric acid for cubic–inverse hexagonal, cubic–cubic and lamellar–cubic transitions. The rate of transition was found to increase with the amplitude of the pressure-jump and with increasing temperature. Evidence for intermediate structures occurring transiently during the transitions was also obtained. In §4 , we describe an IDL-based ‘ AXcess ’ software package being developed in our laboratory to permit batch processing and analysis of the large X-ray datasets produced by pressure-jump synchrotron experiments. In §5 , we present some recent results on the fluid lamellar– Pn 3 m cubic phase transition of the single-chain lipid 1-monoelaidin, which we have studied both by pressure-jump and temperature-jump X-ray diffraction. Finally, in §6 , we give a few indicators of future directions of this research. We anticipate that the most useful technical advance will be the development of pressure-jump apparatus on the microsecond time-scale, which will involve the use of a stack of piezoelectric pressure actuators. The pressure-jump technique is not restricted to lipid phase transitions, but can be used to study a wide range of soft matter transitions, ranging from protein unfolding and DNA unwinding and transitions, to phase transitions in thermotropic liquid crystals, surfactants and block copolymers.

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32

Siegel, D. P., W. J. Green, and Y. Talmon. "Studying the mechanism of Lα/HII and Lα/QII phase transmissions in phospholipid liquid crystals with temperature-jump cryo-TEM." Proceedings, annual meeting, Electron Microscopy Society of America 52 (1994): 432–33. http://dx.doi.org/10.1017/s0424820100169894.

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The transitions between lamellar (Lα), inverted cubic (QII), and inverted hexagonal (HII) liquid crystalline phases can be very rapid, despite drastic changes in system topology. The Lα phase is a stack of flat lipid bilayers, the HII phase is a hexagonal array of inverted rod micelles, and the QII phase is a lipid bilayer labyrinth with the geometry of an infinite periodic minimal surface. The mechanism of the transitions from the Lα a phase are of particular interest: they start with interbilayer events that are related to the process of biomembrane fusion, a ubiquitous and essential process in cellular function. Previous theoretical work suggested two possible mechanisms for these transitions. We have studied these transitions using time-resolved cryo-TEM. Earlier, we used on-the-grid mixing techniques to trigger the transition and observe some of the intermediates that form within seconds. Here we use a novel temperature-jump cryo-TEM technique which triggers the phase transition several milliseconds before vitrification. We extend the initial results obtained with this apparatus and reinterpret them in terms of a new theory of the transition mechanism.

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33

Chandra, Dhanesh, Renee A. Lynch, Wei Ding, and John J. Tomlinson. "Phase Diagram Studies on Neopentylglycol and Pentaerythritol-Thermal Energy Storage Materials." Advances in X-ray Analysis 33 (1989): 445–52. http://dx.doi.org/10.1154/s037603080001987x.

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AbstractPentaerythritol (PE) and neopentylglycol (NPG) are organic molecular crystals which have hydrogen-bonded lattices with layered- and chain-type structures, respectively. The PE undergoes solid-state phase transitions at 416K, from tetragonal to a cubic (γ’) structure and NPG also undergoes this transition at 317K from a monoclinic to a cubic (γ) structure. The phase transitions in binary PE-NPG solid solutions show more than one solid-solid transition in which the NPG-rich β transforms to γ at a constant temperature but the transition of the PE-rich a phase to γ’ passes through a two-phase field at a temperature that varies as a function of composition. Structural analyses by high-temperature x-ray diffractometry have revealed some new, interesting transitions. A phase diagram has been constructed for 0-30 mol% NPG in the PE-NPG system, using x-ray diffraction and differential scanning calorimetry results, and work is in progress to complete this diagram. The variation of lattice parameters as a function of temperature in the α, γ and γ’ phases for PE+20 mol% NPG are presented here, together with a discussion of phase transitions for certain compositions.

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Alert, Ricard, Pietro Tierno, and Jaume Casademunt. "Mixed-order phase transition in a colloidal crystal." Proceedings of the National Academy of Sciences 114, no. 49 (November 20, 2017): 12906–9. http://dx.doi.org/10.1073/pnas.1712584114.

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Mixed-order phase transitions display a discontinuity in the order parameter like first-order transitions yet feature critical behavior like second-order transitions. Such transitions have been predicted for a broad range of equilibrium and nonequilibrium systems, but their experimental observation has remained elusive. Here, we analytically predict and experimentally realize a mixed-order equilibrium phase transition. Specifically, a discontinuous solid–solid transition in a 2D crystal of paramagnetic colloidal particles is induced by a magnetic field H. At the transition field Hs, the energy landscape of the system becomes completely flat, which causes diverging fluctuations and correlation length ξ∝|H2−Hs2|−1/2. Mean-field critical exponents are predicted, since the upper critical dimension of the transition is du=2. Our colloidal system provides an experimental test bed to probe the unconventional properties of mixed-order phase transitions.

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35

Shaginyan, V. R., J. G. Han, and J. Lee. "Fermion condensation quantum phase transition versus conventional quantum phase transitions." Physics Letters A 329, no. 1-2 (August 2004): 108–15. http://dx.doi.org/10.1016/j.physleta.2004.06.065.

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36

Pleiner, H., H. R. Brand, and P. E. Cladis. "Phase transitions in biaxial banana phases." Ferroelectrics 243, no. 1 (May 2000): 291–99. http://dx.doi.org/10.1080/00150190008008030.

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37

Ng, T. K. "Overview of phases and phase transitions." Philosophical Magazine 95, no. 26 (September 12, 2015): 2918–47. http://dx.doi.org/10.1080/14786435.2015.1068960.

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Huber, P., H. Krummeck, J. Baller, J. K. Krüger, K. Knorr, and S. Haussühl. "Phases and phase transitions of KPF6." Ferroelectrics 203, no. 1 (November 1997): 211–19. http://dx.doi.org/10.1080/00150199708012847.

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39

Quinn, P. J. "Measurement of Kinetics and Mechanisms of Phase Transitions in Lipid–Water Systems." Journal of Applied Crystallography 30, no. 5 (October 1, 1997): 733–38. http://dx.doi.org/10.1107/s0021889897001155.

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The lipids from biological membranes, when dispersed in aqueous media, form a variety of phases that include bilayer and nonbilayer arrangements of the molecules. Such phases have been well characterized by conventional X-ray powder diffraction and other methods. Transitions between phases are believed to underlie a number of dynamic membrane processes such as membrane fusion. Studies of the kinetics and mechanisms of phase transitions in lipid–water mixtures require high-intensity synchrotron X-ray sources to monitor the associated structural changes. Facilities at four synchrotron sources providing facilities to measure kinetics and mechanisms of phase transitions in lipid–water systems are described. Some examples are given of how these facilities have been used to measure kinetics of transitions in the dipalmitoylphosphatidylcholine–water system and how different transition mechanisms are defined.

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Andriushchenko, Petr Dmitrievich, and Konstantin Valentinovich Nefedev. "Magnetic Phase Transitions in the Lattice Ising Model." Advanced Materials Research 718-720 (July 2013): 166–71. http://dx.doi.org/10.4028/www.scientific.net/amr.718-720.166.

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In this paper we consider an approach, which allows the research of order-disorder transitionin lattice systems (with any distribution of the exchange integrals) in the frame of Ising model. Anew order parameters, which can give a description of a phase transitions, are found. The commondefinition of such order parameter is the mean value of percolation cluster size. Percolation clusterincludes spins in ground state. The transition from absolute disorder to correlated phase could bestudied with using of percolation theory methods.

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41

Goldman, A. M. "SUPERCONDUCTOR-INSULATOR TRANSITIONS." International Journal of Modern Physics B 24, no. 20n21 (August 30, 2010): 4081–101. http://dx.doi.org/10.1142/s0217979210056451.

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Superconductor-insulator transitions, especially in thin films, can provide the simplest examples of the continuous quantum phase transition paradigm. Quantum phase transitions differ from thermal phase transitions in that they occur at zero temperature when the ground state of a system is changed in response to a variation of an external parameter of the Hamiltonian. In the example of the superconductor-insulator transition, this control parameter could be the parallel or perpendicular magnetic field, disorder, or charge density. Quantum phase transitions are studied through measurements at nonzero temperature of physical behaviors influenced by the quantum fluctuations associated with the transition. This review will focus on experimental aspects of superconductor-insulator transition in disordered films that are effectively two-dimensional. In particular, the evidence for quantum critical behavior in the various types of transitions will be presented. The various theoretical scenarios for the transitions will also be discussed along with the extent to which they are supported by experiment. Open questions relating to the nature of the very puzzling insulating regime and whether there are many different types of superconductor-insulator transitions will be presented. Although this research area is more than 20 years old, rather central issues are not resolved.

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Zhou, Ling. "Nanoparticles-Induced Phase Transitions in A(BC)₃ Miktoarm Star Copolymers." Advanced Materials Research 905 (April 2014): 23–27. http://dx.doi.org/10.4028/www.scientific.net/amr.905.23.

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Phase transitions induced by nanoparticles in A(BC)3 miktoarm star copolymers are investigated by using self-consistent field and density functional theories. With increasing nanoparticle concentration, a variety of phase transitions are observed, including the transition from a hexagonal lattice phase with beads at the interface to a core-shell hexagonal lattice phase, the transition from a core-shell hexagonal lattice phase to a three-color lamellar phase, and the transition from a lamellar phase with beads at the interface to a three-color lamellar phase. The results provide an effective control mechanism for obtaining the desired microstructures and realizing their transitions.

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Irfan, Sheheera, Yasir A. Haleem, Muhammad Imran Irshad, Muhammad Farooq Saleem, Muhammad Arshad, and Muhammad Habib. "Tunability of the Optical Properties of Transition-Metal-Based Structural Phase Change Materials." Optics 4, no. 2 (May 24, 2023): 351–63. http://dx.doi.org/10.3390/opt4020026.

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Phase transitions are an intriguing yet poorly understood aspect of transition-metal-based materials; these phase transitions can result in changes to the refractive index, absorption coefficient, and other optical properties of the materials. Transition-metal-based materials exist in a variety of crystalline phases and also have metallic, semi-metallic, and semi-conducting characteristics. In this review, we demonstrate that alloyed W- and Mo-based dichalcogenides enable phase transitions in structures, with phase transition temperatures that are tunable across a wide range using various alloy models and modern DFT-based calculations. We also analyze the tuning the optical bandgap of the metal oxide nanoparticles through doping of the transition metal in a manner that is suitable for optical switching and thermal imaging. After the introduction and a brief illustration of the structures and their exceptional properties, we discuss synthetic methodologies and their application as part of important strategies toward the enhanced performance of transition-metal-based dichalcogenides and oxides. In the end, our conclusion highlights the prospects of 2D materials as phase transition materials due to their advantages in terms of scalability and adaptability.

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Dexheimer, V., L. T. T. Soethe, J. Roark, R. O. Gomes, S. O. Kepler, and S. Schramm. "Phase transitions in neutron stars." International Journal of Modern Physics E 27, no. 11 (November 2018): 1830008. http://dx.doi.org/10.1142/s0218301318300084.

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In this paper, we review the most common descriptions for the first-order phase transition to deconfined quark matter in the core of neutron stars. We also present a new description of these phase transitions in the core of proto-neutron stars, in which more constraints are enforced so as to include trapped neutrinos. Finally, we calculate the emission of gravitational waves associated with deconfinement phase transitions, discuss the possibility of their detection, and how this would provide information about the equation of state of dense matter.

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Tarawneh, Khaldoun, and Yahya Al-Khatatbeh. "Phase Relations of Ni2In-Type and CaC2-Type Structures Relative to Fe2P-Type Structure of Titania at High Pressure: A Comparative Study." Crystals 13, no. 1 (December 21, 2022): 9. http://dx.doi.org/10.3390/cryst13010009.

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Density functional theory (DFT) based on first-principles calculations was used to study the high-pressure phase stability of various phases of titanium dioxide (TiO2) at extreme pressures. We explored the phase relations among the following phases: the experimentally identified nine-fold hexagonal Fe2P-type phase, the previously predicted ten-fold tetragonal CaC2-type phase of TiO2, and the recently proposed eleven-fold hexagonal Ni2In-type phase of the similar dioxides zirconia (ZrO2) and hafnia (HfO2). Our calculations, using the generalized gradient approximation (GGA), predicted the Fe2P → Ni2In transition to occur at 564 GPa and Fe2P → CaC2 at 664 GPa. These transitions were deeply investigated with reference to the volume reduction, coordination number decrease, and band gap narrowing to better determine the favorable post-Fe2P phase. Furthermore, it was found that both transitions are mostly driven by the volume reduction across transitions in comparison with the small contribution of the electronic energy gain. Additionally, our computed Birch–Murnaghan equation of state for the three phases reveals that CaC2 is the densest phase, while Ni2In is the most compressible phase.

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Florêncio, Odila, Paulo Sergio Silva, José Antônio Eiras, Ducinei Garcia, and Eriton Rodrigo Botero. "Study of the Anelastic Behavior of PZT and PLZT Ferroelectric Ceramics." Defect and Diffusion Forum 326-328 (April 2012): 719–24. http://dx.doi.org/10.4028/www.scientific.net/ddf.326-328.719.

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The anelastic behavior of the ferroelectric ceramics (Pb)(Zr/Ti)O3(PZT) and (Pb/La)(Zr/Ti)O3(PLZT), with Zr/Ti = 65/35, La = 5 at.% and 8 at.%, was investigated in the region of the ferroelectric phase transitions. Anelastic spectroscopy experiments were performed in an acoustic elastometer system, operating in a kilohertz bandwidth, at temperatures rising from 300 K to 770 K, at a heating rate of 1 K/min, under pressure of 10-5mbar. Anelastic measurements on PZT showed only one anomaly, associated with the occurrence of a ferroelectric-paraelectric phase transition, while the PLZT data showed two anomalies, which were associated with the following transitions: the ferroelectric-paraelectric phase transition and a ferro-ferroelectric phase transition between distinct rhombohedral ferroelectric phases. The behavior of the relative variation of the elastic moduli with temperature, near the phase transitions, which describes the change in the type of coupling between strain and the order parameter in ferroelectric-paraelectric phase transition, with the increase of lanthanum amount and, linear coupling in the strain and order parameter type to PZT ceramic and linear coupling in the strain but quadratic in order parameter type for PLZT ceramics.

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47

FENG, HONG-JIAN, XIAOYUN HU, and HUIJUAN CHEN. "STRUCTURAL AND MAGNETIC PHASE TRANSITIONS OF BiFeO3 INDUCED BY PRESSURE." Functional Materials Letters 06, no. 03 (May 28, 2013): 1350026. http://dx.doi.org/10.1142/s1793604713500264.

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First-principles calculations on BiFeO3 under low-pressure region show that the rhombohedral-monoclinic and rhombohedral-orthorhombic phase transitions can be found around the critical pressure value, ~9 GPa.We suggest that the structure involve the combination of these three phases and change to the pure orthorhombic phase gradually as pressure is beyond the critical value. Moreover, it is a first-order structural phase transition, accompanied with antiferromagnetic–ferromagnetic transition.

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48

Ivancic, Robert J. S., and Robert A. Riggleman. "Dynamic phase transitions in freestanding polymer thin films." Proceedings of the National Academy of Sciences 117, no. 41 (October 2, 2020): 25407–13. http://dx.doi.org/10.1073/pnas.2006703117.

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After more than two decades of study, many fundamental questions remain unanswered about the dynamics of glass-forming materials confined to thin films. Experiments and simulations indicate that free interfaces enhance dynamics over length scales larger than molecular sizes, and this effect strengthens at lower temperatures. The nature of the influence of interfaces, however, remains a point of significant debate. In this work, we explore the properties of the nonequilibrium phase transition in dynamics that occurs in trajectory space between high- and low-mobility basins in a set of model polymer freestanding films. In thick films, the film-averaged mobility transition is broader than the bulk mobility transition, while in thin films it is a variant of the bulk result shifted toward a higher bias. Plotting this transition’s local coexistence points against the distance from the films’ surface shows thick films have surface and film-center transitions, while thin films practically have a single transition throughout the film. These observations are reminiscent of thermodynamic capillary condensation of a vapor–liquid phase between parallel plates, suggesting they constitute a demonstration of such an effect in a trajectory phase transition in the dynamics of a structural glass former. Moreover, this transition bears similarities to several experiments exhibiting anomalous behavior in the glass transition upon reducing film thickness below a material-dependent onset, including the broadening of the glass transition and the homogenization of surface and bulk glass transition temperatures.

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Makal, Anna. "Triethylphosphine as a molecular gear — phase transitions in ferrocenyl–acetylide–gold(I)." Acta Crystallographica Section B Structural Science, Crystal Engineering and Materials 74, no. 5 (August 24, 2018): 427–35. http://dx.doi.org/10.1107/s2052520618010399.

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A sequence of two discontinuous phase transitions, occurring just above 125 K and 148 K, has been observed for a ferrocenyl–acetylide–gold(I) complex with triethylphosphine, structure (1), by means of a multi-temperature single-crystal X-ray diffraction technique. Three distinct phases have been identified. The high-temperature α and low-temperature γ phases share the same space group Pbca, whereas the intermediate β phase is in the Pb21 a subgroup of Pbca. In all phases molecules of (1) form well defined double layers, with PEt3 groups interlocking in planes perpendicular to c. On the molecular level, both phase transitions involve almost uniquely a conformational change of triethylphosphine: a gear-like rotation around the P—Au axis and concerted flips of the ethyl moieties. The mechanism of these transitions may be imagined as initiated by a rotation of a single PEt3 group in a double layer (a single gear movement), followed by adjacent phosphines adjusting their conformations as a result of steric strain. The structural changes underlying phase transitions are sequential, occurring layer-wise, the γ→β transition involving approximately every other layer in the crystal lattice, the β→α yielding a total conformation change. The sequence of phase transitions results in a noticeable contraction of the crystal cell volume.

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HEISELBERG, HENNING. "NEUTRON STARS: RECENT DEVELOPMENTS." International Journal of Modern Physics B 15, no. 10n11 (May 10, 2001): 1519–34. http://dx.doi.org/10.1142/s0217979201006008.

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Recent developments in neutron star theory and observation are discussed. Based on modern nucleon-nucleon potentials more reliable equations of state for dense nuclear matter have been constructed. Furthermore, phase transitions such as pion, kaon and hyperon condensation, superfluidity and quark matter can occur in cores of neutron stars. Specifically, the nuclear to quark matter phase transition and its mixed phases with intriguing structures are treated. Rotating neutron stars with and without phase transitions are discussed and compared to observed masses, radii and glitches. The observations of possible heavy ~2M⊙ neutron stars in X-ray binaries and quasi-periodic oscillations require relatively stiff equations of state and restrict strong phase transitions to occur at very high nuclear densities only.

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