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Mould-cast Nd 60 Fe 40− x Al x ( x =0, 5, 10) alloys were studied to clarify the effect of Al on the structural and magnetic properties. For binary Nd 60 Fe 40 , the metastable hard magnetic A 1 phase forms along with the Nd 2 Fe 17 equilibrium phase. Partial substitution of Fe by Al favours the formation of the hard magnetic metastable A 1 phase manifested by a large magnetization.

We present an overview of recent research applying ideas of statistical physics to try to better understand puzzles regarding economic fluctuations. One of these puzzles is how to describe outliers, phenomena that lie outside of patterns of statistical regularity. We review evidence consistent with the possibility that such outliers may not exist. This possibility is supported by recent analysis by Plerou et al. of a database containing the bid, ask, and sale price of each trade of every stock. Further, the data support the picture of economic fluctuations, due to Plerou et al., in which a financial market alternates between being in an “equilibrium phase” where market behavior is split roughly equally between buying and selling, and an “out-of-equilibrium phase” where the market is mainly either buying or selling.

The behavior of crystalline tetraalkylammonium salts at 290–350 K was studied by differential scanning calorimetry. For tetraethyl- and tetrabutylammonium bromides (Et4NBr and Bu4NBr), the experimental heat capacities agreed well with the literature values. For tetrahexyl-, tetraheptyl-, and tetraoctylam-monium bromides (Hex4NBr, Hep4NBr, and Oct4NBr), phase transitions were found between crystal modifications whose characteristic temperatures depended significantly on the size of the cation. Empirical equations for the temperature dependences of the heat capacities of the salts within the ranges of homogeneous equilibrium phases were derived.

The processing of cold rolled intercritically annealed steels which exhibit transformation induced plasticity (TRIP) requires the precise determination of equilibrium parameters, the kinetics of the intercritical γ phase formation and the kinetics of the isothermal bainitic transformation. In addition, the aging phenomena associated with the bainitic transformation must be taken into account. A detailed analysis of the kinetics of the combination of both transformations carried out in succession has hitherto not been reported. The present contribution proposes an empirical method to study these transformations in low C intercritically annealed TRIP steels: a standard CMnSi TRIP steel and a CMnAlSi TRIP steel in which part of the Si is replaced by Al. The latter TRIP steel is more likely to be used in continuous galvanising lines. Dilatometry was used to determine the soaking time necessary to obtain the equilibrium phase distribution during the intercritical annealing. Furthermore, the transformat...

First, we present a two-dimensional lattice gas model with anisotropic interactions which explains the experimentally observed transition from a dominant c(2x2) ordering of the CdTe(001) surface to a local (2x1) arrangement of the Cd atoms as an equilibrium phase transition. Its analysis by means of transfer-matrix and Monte Carlo techniques shows that the small energy difference of the competing reconstructions determines to a large extent the nature of the different phases. Then, this lattice gas is extended to a model of a three-dimensional crystal which qualitatively reproduces many of the characteristic features of CdTe which have been observed during sublimation and atomic layer epitaxy., 5 pages, 3 figures

Pulmonary surfactant functions by first flowing rapidly into the alveolar air/water interface, but then resisting collapse from the surface when the adsorbed interfacial film is compressed during exhalation. Widely accepted models emphasize the importance of phase behavior in both processes. Recent studies show, however, that fluidity is a relatively minor determinant of adsorption and that solid films, which resist collapse, can form by kinetic processes unrelated to equilibrium phase behavior.

We review the currently known universality classes of continuous phase transitions to absorbing states in nonequilibrium systems and present results of simulations and arguments to show how the blockades introduced by different particle species in one dimension cause new robust classes. Results of investigations on the dynamic scaling behavior of some bosonic spreading models are reported., New section added about simulation results of some one component bosonic spreading processes. Proc. of LAWNP01 Cocoyoc Mexico 2001. 13 pages 3 figures

Nanostractural alloys have attracted growing interest because of their potential properties. The recent studies on nanostructured alloys imply the reality of alloy designing without restriction by the equilibrium phase diagram. We review recent results in new alloys developed by mechanical alloying technique and emphasize their potentiality as future materials.

In a recent publication [Maćkowiak et al., J. Chem. Phys. 145, 164704 (2016)] the results of Non-Equilibrium Molecular Dynamics (NEMD) simulations of confined sheared Lennard-Jones molecular films have been presented. The present work builds on that study by focusing on the low wall speed (shear rate) regime. Maps are given of the steady-state structures and corresponding friction coefficients in the region where a transition from static to kinetic friction is observed. The boundary between static and kinetic friction regions is determined as a function of wall speed and applied pressure, which is located for wall speeds up to about 0.8 m s−1. It was found that stick-slip behavior extends to pressures as high as 1000 MPa. The NEMD equations of motion are shown to be consistent with the Prandtl–Tomlinson model in the ‘soft spring’ limit, which leads to a new expression for the friction coefficient. This study provides new details and insights into the nature of anomalous friction behavior in the so-called Plug-Slip part of the nonquilibrium phase diagram regime.

Biological functions rely on ordered structures and intricately controlled collective dynamics. Such order in living systems is typically established and sustained by continuous dissipation of energy. The emergence of ordered patterns of motion is unique to non-equilibrium systems and is a manifestation of dynamic steady states. Many cellular processes require transitions between different steady states. Can general principles of statistical physics guide our understanding of such cellular self-organization? I will show that model actomyosin cortices, in the presence of rapid turnover, self-organize into three non-equilibrium steady states as a function of network connectivity. The different states arise from a subtle interaction between mechanical percolation of the actin network and myosin-generated stresses. All states show distinct dynamic order. Only the highest connectivity causes structural phase separation. We discover that the dominant mechanism defining the symmetries of the dynamic steady states is the emergence of ordered stress patterns. The marginally percolated state displays strong strain fluctuations, indicative of enhanced susceptibility. The striking dynamics in this model actomyosin cortex were revealed using fluorescent single-walled carbon nanotubes as novel probes. We propose self-organization of stress patterns as a new paradigm of biological function.

Telluride misfit layer compounds are reported for the first time. These compounds were synthesized using a novel approach of structurally designing a precursor that would form the desired product upon low-temperature annealing, which allows the synthesis of kinetically stable products that do not appear on the equilibrium phase diagram. Four new compounds of the [(PbTe)1.17]m(TiTe2)n family are reported, and their structures were examined by a variety of X-ray diffraction techniques.

Centrosomes are highly dynamic, spherical organelles without a membrane. Their physical nature and their assembly are not understood. Using the concept of phase separation, we propose a theoretical description of centrosomes as liquid droplets. In our model, centrosome material occurs in a form soluble in the cytosol and a form that tends to undergo phase separation from the cytosol. We show that an autocatalytic chemical transition between these forms accounts for the temporal evolution observed in experiments. Interestingly, the nucleation of centrosomes can be controlled by an enzymatic activity of the centrioles, which are present at the core of all centrosomes. This nonequilibrium feature also allows for multiple stable centrosomes, a situation that is unstable in equilibrium phase separation. Our theory explains the growth dynamics of centrosomes for all cell sizes down to the eight-cell stage of the Caenorhabditis elegans embryo, and it also accounts for data acquired in experiments with aberrant numbers of centrosomes and altered cell volumes. Furthermore, the model can describe unequal centrosome sizes observed in cells with perturbed centrioles. We also propose an interpretation of the molecular details of the involved proteins in the case of C. elegans. Our example suggests a general picture of the organization of membraneless organelles.

In this paper we present rigorous results on the critical behavior of the Activated Random Walk model. We conjecture that on a general class of graphs, including Z d , and under general initial conditions, the system at the critical point does not reach an absorbing state. We prove this for the case where the sleep rate λ is infinite. Moreover, for the one-dimensional asymmetric system, we identify the scaling limit of the flow through the origin at criticality. The case λ < +∞ remains largely open, with the exception of the one-dimensional totally-asymmetric case, for which it is known that there is no fixation at criticality. Fil: Cabezas, M.. Conselho Nacional de Desenvolvimiento Cientf y Tec. Associacao Instituto Nacional de Matemática Pura E Aplicada; Brasil Fil: Trivellato Rolla, Leonardo. Conselho Nacional de Desenvolvimiento Cientf y Tec. Associacao Instituto Nacional de Matemática Pura E Aplicada; Brasil. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Sidoravicius, V.. Conselho Nacional de Desenvolvimiento Cientf y Tec. Associacao Instituto Nacional de Matemática Pura E Aplicada; Brasil

The classical non-linear climatic model previously developed by Saltzman with co-authors and Nicolis is analysed in both the deterministic and stochastic cases in a wider domain of system parameters. A detailed analysis of the deterministic model shows a co-existence of a stable cycle and equilibrium phase points of the climate system localisation. A fine structure of attraction basins existing around stable equilibria is studied. The model under consideration possesses the noise-induced transitions between possible system attractors (limit cycle and two equilibria) in the case of stochastic dynamics caused by temperature fluctuations. A new phenomenon of stochastic generation of large amplitude oscillations around two equilibrium points in the absence of a limit cycle is revealed. The co-existence of large-, small- and mixed-mode stochastic transitions between the climate system attractors is found. Keywords: climatic model, stochastic disturbances, noise-induced transitions, attraction basins (Published: 25 April 2014) Citation: Tellus A 2014, 66 , 23454, http://dx.doi.org/10.3402/tellusa.v66.23454

The Chaotic Multiquenching Annealing algorithm (CMQA) is proposed. CMQA is a new algorithm, which is applied to protein folding problem (PFP). This algorithm is divided into three phases: (i) multiquenching phase (MQP), (ii) annealing phase (AP), and (iii) dynamical equilibrium phase (DEP). MQP enforces several stages of quick quenching processes that include chaotic functions. The chaotic functions can increase the exploration potential of solutions space of PFP. AP phase implements a simulated annealing algorithm (SA) with an exponential cooling function. MQP and AP are delimited by different ranges of temperatures; MQP is applied for a range of temperatures which goes from extremely high values to very high values; AP searches for solutions in a range of temperatures from high values to extremely low values. DEP phase finds the equilibrium in a dynamic way by applying least squares method. CMQA is tested with several instances of PFP. © 2014 Juan Frausto-Solis et al.

As a result of important advances over the last decade, block copolymer melts have become an excellent model system for studying fundamental phenomena associated with molecular self-assembly. During this time, good quantitative agreement has been achieved between theory and experiment in regards to equilibrium phase behaviour, and with it has emerged a thorough understanding in terms of simple intuitive explanations. The theoretical contributions to this effort are largely attributed to mean-field calculations on a standard Gaussian model. Here, we review this present understanding of block copolymer phase behaviour, the model and its underlying assumptions, the mean-field approximation and its limitations, and the attempts to incorporate fluctuation corrections. Rather than following the traditional rigorous derivations, we present slightly more intuitive and transparent ones in such a way to stress the close connection between the related calculations. In this way, we hope to provide a valuable introduction to block copolymer theory.

An approximate solution is presented to the phase equilibrium problem for the case of a partially miscible polymer solution or a binary heteropolymer blend. It is based on the Flory–Huggins theory and is valid for mixtures well into the phase-separated region. Analytical expressions are derived for the extent and composition of each of the two coexisting phases as a function of the component molecular size and interaction strength. These results are combined with Helfand's model to provide estimates for the interfacial tension and thickness and, therefore, a measure of the quality of the interfacial bonding in a polymer/polymer blend. They are also utilized in conjunction with a free volume theory approach for calculating the mutual diffusion coefficient of a penetrant, migrating through a polymer.

New model for solute redistribution in cellular/dendritic growth has been applied to predict the amount of non-equilibrium precipitates. Both real and theoretical redistribution of the Zn-solute within Al-75Zn alloy is taken into account to show the model application. The amount of non-equilibrium precipitates is determined for the explored morphology.

Investigations of changes in phase composition and mechanical properties of CeO 2 - and Y 2 O 3 - stabilized plasma-sprayed ZrO 2 -based thermal barrier coatings (TBC) after long-term heat treatments at typical service temperatures were performed. Experimental studies include X-ray diffraction and mechanical testing. TBCs with a high amount of the tetragonal equilibrium phase t (8 mol-% CeO 2 ) show strong degradation due to the high amount of transformation to the monoclinic phase and the related decrease in strength. TBCs with a high amount of tetragonal or cubic non-equilibrium phases t' or c' are more suitable. Among these, TBCs with higher CeO 2 -stabilizer contents (19.5 mol-% CeO 2 /1.5 mol-% Y 2 O 3 and 35 mol-% CeO 2 ) show less amounts of monoclinic phase with respect to Y 2 O 3 -stabilized TBCs (4.5 mol-% Y 2 O 3 ), as commercially used. Therefore they seem to have a high potential for long-term applications.

Alcohol flooding, consisting of injection of a mixture of alcohol and water, is one source removal technology for dense non-aqueous phase liquids (DNAPLs) currently under investigation. An existing compositional multiphase flow simulator (UTCHEM) was adapted to accurately represent the equilibrium phase behavior of ternary and quaternary alcohol/DNAPL systems. Simulator predictions were compared to laboratory column experiments and the results are presented here. It was found that several experiments involved unstable displacements of the NAPL bank by the alcohol flood or of the alcohol flood by the following water flood. Unstable displacement led to additional mixing compared to ideal displacement. This mixing was approximated by a large dispersion in one-dimensional simulations and or by including permeability heterogeneities on a very small scale in three-dimensional simulations. Three-dimensional simulations provided the best match. Simulations of unstable displacements require either high-resolution grids, or need to consider the mixing of fluids in a different manner to capture the resulting effects on NAPL recovery.

Equilibrium phase diagrams of mixtures of propoxylated glyceroltriacrylate (GPTA) and the low molecular weight liquid crystal 4-cyano-4′-pentyl-biphenyl (5CB) are studied. The diagrams of monomeric and electron beam (EB) cured GPTA/5CB blends are established using polarized optical microscopy and differential scanning calorimetry techniques. The experimental data are successfully analyzed using mean field models and a reasonable choice of parameters.

An existing vapor–liquid equilibrium facility has been automated to measure simultaneously liquid and vapor equilibrium phase compositions, phase densities, and interfacial tensions. Experimental measurements have been made for CO 2 +decane at 344.3 K. The newly acquired data were compared with those of five other sources. Excellent agreement was observed for the phase densities of this work and those of Nagarajan et al. Reasonable agreement exists for all liquid phase compositions (within 0.005 mole fraction CO 2 ) except for those of Chou et al. Vapor phase compositions of all data sets agree to within 0.005 mole fraction CO 2 . These data extend the range of previous data collected at Oklahoma State University and demonstrate the viability of new computer automation systems and of a new digitized imaging procedure for measurement of interfacial tensions.

High-energy ball milling of Fe–Mn elemental powder mixtures has been carried out for different Mn concentrations, ranging from 0 to 90%. Mossbauer spectroscopy of 57Fe and perturbed angular correlations with 111In – implanted at 400 keV into pills made from the milled powders – have been used to investigate the structure of the milled samples. Clear changes of the hyperfine spectra occur at Mn concentrations of 15–20% and above 70%, indicating extended concentration ranges of α-Fe and γ-Fe(Mn), compared to the equilibrium phase diagram. Detailed information on additional lower hyperfine fields due to nearest neighbor Mn atoms has been obtained in the α-Fe phase containing up to 20% Mn .

Using a molten salt method, EMF measurements have been obtained for In–Sb, Sb–Sn and In–Sb–Sn alloys. New DSC experiments on Sb–Sn system gave a confirmation of the proposed Sb–Sn equilibrium phase diagram. A thermodynamic description of the ternary liquid in fair agreement with the experimental results has been obtained from the geometrical Muggianu approach.

The chemical transformations of γ-Al(OH)3during closed-system heat treatment in a self-generated gaseous atmosphere (water vapor) were studied. At t≥ 200°C, γ-Al(OH)3was found to convert into γ-AlOOH, which, in turn, converts into the equilibrium phase α-Al2O3at t≥ 400°C. The processes underlying the effect of water vapor on the kinetics and mechanisms of the chemical transformations of γ-Al(OH)3and γ-AlOOH in a closed system are discussed.

In order to determine the crystalline phases which coexist with the icosahedral quasicrystalline phase at high temperatures, an isothermic section of the AlCuFe equilibrium phase diagram at 850°C was studied. This section is near to composition and temperature values where the icosahedral phase was formed from the cubic phase. The quasicrystalline phase is not found in a region of a single phase. However, it has binary stability fields with the cubic β-Al 5 (Cu,Fe) 5 phase and ternary stability fields with the β+λ-Al 13 Fe 4 .

An ion beam mixing experiment for Cu–Zr system was conducted and two supersaturated solid solutions were observed with compositions of 16 atom% Zr in Cu and 17 atom% Cu in Zr, respectively, which are much greater than almost nil found from the equilibrium phase diagram of Cu–Zr system. The observation indicates that Cu–Zr metallic glasses could possibly be obtained in composition range bounded by the two observed solid solubilities, i.e. 16–83 atom% Zr. Besides, a unique Cu 65 Zr 35 metallic glass was obtained by ion beam mixing and its composition is very close to the so-called best composition referred in the literature.

We study the surface phase diagram of the three-dimensional kinetic Ising model below the equilibrium critical point subjected to a periodically oscillating magnetic field. Changing the surface interaction strength as well as the period of the external field, we obtain a non-equilibrium surface phase diagram that in parts strongly resembles the corresponding equilibrium phase diagram, with an ordinary transition, an extraordinary transition and a surface transition. These three lines meet at a special transition point. For weak surface couplings, however, the surface does not order. These results are found to remain qualitatively unchanged when using different single-spin flip dynamics., 11 pages, 5 figures, accepted for publication in Physical Review E

By finding local minima of a thermodynamic-like potential, we generate jammed packings of frictionless spheres under constant shear stress σ and obtain the yield stress σy by sampling the potential energy landscape. For three-dimensional systems with harmonic repulsion, σy satisfies the finite size scaling with the limiting scaling relation σy∼ϕ-ϕc,∞, where ϕc,∞ is the critical volume fraction of the jamming transition at σ=0 in the thermodynamic limit. The finite size scaling implies a length ξ∼(ϕ-ϕc,∞)-ν with ν=0.81±0.05, which turns out to be a robust and universal length scale exhibited as well in the finite size scaling of multiple quantities measured without shear and independent of particle interaction. Moreover, comparison between our new approach and quasistatic shear reveals that quasistatic shear tends to explore low-energy states.

Before setting out to a conclusion of the critical analysis of structural transformation of kaolinite as described in Chaps. 19–25, it is important to recapitulate the past and present scenario on thermal decomposition of it. Kaolin at high temperature finally transforms to yield stable mullite phase and β-cristobalite as per the prediction of equilibrium phase diagram of the SiO2-Al2O3 system. Many investigations explained the fundamentals of the breakdown of kaolinite and the subsequent recrystallization of it to mullite. Although intermediate steps of reaction have been extensively studied the interpretations are full of controversies. It is reviewed that even with the application of many recent experimental techniques to resolve one of the most interesting crystallo–chemical problems of K-M reaction series, a few areas are yet to be solved or there is absence of general agreement on various issues.

The principles of cancer immunoediting have set the foundations for understanding the dual host-protective and tumour sculpting actions of immunity on cancer and establishing the basis for novel individualized cancer immunotherapies. During cancer immunoediting, the host immune system shapes tumour fate in three phases through the activation of innate and adaptive immune mechanisms. In the first phase, Elimination, transformed cells are destroyed by a competent immune system. Sporadic tumour cells that manage to survive immune destruction may then enter an Equilibrium phase where editing occurs. The Escape phase represents the third and final phase of the process, where immunologically sculpted tumours begin to grow progressively, become clinically apparent and establish an immunosuppressive tumour microenvironment. This review focuses on important recent developments that have enhanced our understanding of each phase of the cancer immunoediting process, summarizes the discovery of new predictive and prognostic biomarkers and discusses development of novel and objectively effective cancer immunotherapies.

A key open question in the glass transition field is whether a finite temperature thermodynamic transition to the glass state exists or not. Recent simulations of coupled replicas in atomistic models have found signatures of a static transition as a function of replica coupling. This can be viewed as evidence of an associated thermodynamic glass transition in the uncoupled system. We demonstrate here that a different interpretation is possible. We consider the triangular plaquette model, an interacting spin system which displays (East model-like) glassy dynamics in the absence of any static transition. We show that when two replicas are coupled there is a curve of equilibrium phase transitions, between phases of small and large overlap, in the temperature-coupling plane (located on the self-dual line of an exact temperature/coupling duality of the system) which ends at a critical point. Crucially, in the limit of vanishing coupling the finite temperature transition disappears, and the uncoupled system is in the disordered phase at all temperatures. We discuss interpretation of atomistic simulations in light of this result., 4 pages, 1 figure

Computed tomography (CT) is essential for the diagnosis of liver tumors. In the CT criteria of hypervascular hepatocellular carcinoma (HCC), the diagnosis is based on hemodynamic findings, such as arterial enhancement, followed by washout in the portal-venous and/or equilibrium phase. In this chapter, typical and atypical findings (HCC mimickers) of HCC on CT and current diagnostic techniques to image HCC were stated.

The effect of thermal vacancies on the hardness of the annealed Fe-40 at.% Al with additives (Zr + B and Zr + Cr) is measured. The effects observed in the temperature dependence of the hardness are compared with the subdivision of the B2 (FeAl) field of the Fe-Al equilibrium phase diagram. (orig.)

Experimental data from the literature on the BaO-TiO 2 quasibinary system have been evaluated to assess the thermodynamic parameters of all the stable phases by means of the CALPHAD (CALculation of PHAse Diagram) method. The two-sublattice ionic solution model was used to describe the liquid phase, while the compound energy model was applied to describe the high-temperature forms of BaTiO 3 . Other compounds were treated as stoichiometric phases. The assessment was conducted using the Thermo-calc software package and a set of parameters was given. Calculated equilibrium phase diagrams and thermochemical properties compared with the experimental data are presented. There is a good agreement between the calculations and the experimental data. Some contradictions are pointed out and discussed.

Pressure-induced amorphization of crystalline compounds is believed to arise due to kinetic hindrance of equilibrium phase transitions, while the final state remains speculative/unknown in most instances. Here, we examine an alternate route to amorphization that it could arise in many complex systems if equilibrium decomposition to more dense-packed daughter compounds is constrained kinetically. It is shown that many systems that exhibit pressure-induced amorphization are also good candidates for pressure-induced decomposition leading to a disordered assemblage, forming equilibrium crystalline materials when subjected to elevated temperatures. The route explains the results in Fe2SiO4 and CaAl2Si2O8 and predicts decomposition of several other compounds at high pressure.

The microstructures of two Al–Li–Mg–Si alloys have been studied by thermodynamic calculation and TEM observation in this paper. The results show that the addition of lithium changes the precipitation behavior of Al–Mg–Si alloys. The calculated Al–Li–Mg–Si phase diagrams are used to investigate the equilibrium phase distribution as a function of temperature for the Al–1.8Li–1.8Mg–0.8Si alloy and Al–1.8Li–2.8Mg–0.8Si alloy. According to calculation, δ′ phase (Al 3 Li) becomes the mayor precipitate in Al–1.8Li–1.8Mg–0.8Si alloy while a few amount of β′(Mg 2 Si) phase and AlLiSi phase precipitate. TEM observation show that δ′ phase and AlLiSi phase are precipitated in Al–1.8Li–1.8Mg–0.8Si and heterogeneous rod Mg 2 Si phase is also observed. Calculation on Al–1.8Li–2.8Mg–0.8Si show that both δ′ phase and Mg 2 Si phase precipitate on aging temperature. Experimental results are in agreement with calculation.

We show how the free-energy landscape of a system, normally used only for calculating its equilibrium phase diagram, can be used to predict the kinetic pathways that are permitted in the course of phase separation. Applications to one particular soft condensed matter system, a colloid-polymer mixture, are briefly described.

The already published data of temperatures and enthalpies of decomposition for mercury-based phases were combined with our experimental results from DSC and low-temperature calorimetry and the data for the Ba-Cu-O system taken from the literature. The consistent set of thermodynamic data of all phases in the Hg-Ba-Cu-O system was used for the calculation of the equilibrium phase composition under varying experimental conditions. The selected sections of the p -p -T stability phase diagram were constructed for the ratio of non-volatile components Ba:Cu s 2:1 and the OH g 2

Phase equilibria in the Tb-Mn-O system during the removal of oxygen from the TbMn2O5 compound in stages were studied by the static method on a vacuum circulation unit (973–1173 K) with subsequent X-ray analysis of quenched solid phases. The dissociation of TbMn2O5 was found to occur in three stages. The temperature dependences of equilibrium oxygen pressure were determined experimentally for the phase equilibria observed. The standard thermodynamic functions of the dissociation and formation from the elements of TbMn2O5 and TbMnO3 were calculated.

Equilibrium phase relations in the U–Zr–Fe ternary system have been investigated experimentally at 853, 973 and 1073 K. The composition of each phase has been determined using the electron probe microanalysis. The differential thermal analysis has also been applied to check the phase relations and examine the stabilities of the ternary compounds. The compositions of the phases found near the sub-binary edges are consistent with the published binary phase diagrams. Three ternary compounds have been found and designated e, λ and χ, the compositions of which are U–(33–50)Zr–33Fe, U–(21–25)Zr–6Fe and U–32Zr–50Fe (at.%), respectively. The single e-phase melts at 1206 ± 5 K. The λ-phase decomposes to e and γ at 999 ± 2 K. The χ-phase exists up to 1168 ± 10 K at the lowest. The equilibrium phase diagrams determined or estimated from the experimental results are consistent with the diagrams calculated using thermodynamic models.

Equilibrium phase diagrams of the p-dichlorobenzene−hexafluorobenzene and the p-chlorotoluene−hexafluorobenzene binary systems are experimentally determined by differential scanning calorimetry and...

The Use of Differential Scanning Calorimetry in Studies of Wax Deposition: Measuring the Solid Formation and Binary Solid-Liquid Equilibrium Phase Diagrams — The studies of wax for- mation in hydrocarbon mixtures, both crudes and refined products such as diesels and fuels, require measuring techniques able to deal with the solid phase behaviour. Experimental data on phase equilibria is important to understand the crystallisation of paraffins and for the development of thermodynamical models, that can describe it. It is here shown how the information obtained from Differential Scanning Calorimetry (DSC) measurements can be used to assess the amount of solid forming when a fluid is cooled and also to make faster measurements of phase diagrams for binary systems where no solid solu- tions exist. The measurements performed with the proposed methods present a good agreement with lit- erature data.

X-ray diffraction data have been used in compiling equilibrium phase diagrams for the Lu−Cr−B and Lu−Mo−B systems at 1270 K. The boride LuB2 dissolves not more than 0.03 molar part of CrB2 and 0.30 molar part of MoB2. The existence of compound LuCrB4 is confirmed (structure of YCrB4 type) and the same for Lu2MoB6 (structure of Y2ReB6 type). A homogeneity regions is identified for the boride Lu2MoB6, which ranges up to the composition LuMoB4.

We discuss the progress in realistic calculations of the optical response of semiconductor surfaces. It concerns numerical developments as well as the better inclusion of many-body effects. We show that the starting point of such calculations, the atomic structure and the surface equilibrium phase, can be now derived with high accuracy. The different steps are described in detail for the computation of the reflectance anisotropy and the exploration of the In-rich InP(001)2 4 surfaces.

H emodynamics of contrast material is a key to the diagnosis of focal liver lesions. Lesions with arterial dominant vascularity will show brisk enhancement during the arterial dominant phase (2030 sec after contrast injection), whereas lesions with portal vein blood supply can appear as hyperenhancing lesions in the portal veindominant phase (60-70 sec after contrast injection). Additionally, some lesions with dense fibrous stroma will show persistent enhancement in the equilibrium phase (2-5 mm after contrast injection). The purpose of this essay is to illustrate the spectrum of helical CT features of hyperenhancing liver lesions according to the phases of hepatic enhancement.