A criterion to locate tricritical points in phase diagrams is proposed. The criterion is formulated in the framework of the Elementary Catastrophe Theory and encompasses all the existing criteria in that it applies to systems described by a generally non symmetric free energy which can depend on one or more order parameters. We show that a tricritical point is given whenever the free energy is ...

The temperature-dependent phase diagrams, from 40 to -50 °C, of the binary (NH4)2SO4/H2O system are derived from data collected in a low-temperature, single-levitated-particle apparatus. The conditions of vapor pressure, temperature, and composition, at which particle phase transitions occur along the path of increasing relative humidity, define the equilibrium phase diagram, whereas the set of...

This work presents a brief introduction on the basics of fiber-optical sensors and an overview focused on the applications to measurements in multiphase reactors. The most commonly principle utilized is laser back scattering, which is also the foundation for almost all current probes used in multiphase reactors. The fiber-optical probe techniques in two-phase reactors are more developed than th...

We propose a new solution to the cosmological monopole problem in which domain walls sweep away the magnetic monopoles and subsequently decay. The solution does not require extensive finetuning or model building; it works for the prototype SUs5d grand unification model. More generally, it shows that defect interactions can lead to “defect erasure” in phase transitions and that this can be relev...

Be honest – what is easier to publish: in vitro or clinical research? But let’s start from the beginning. The “pyramid of evidence” ranks like this: 1a: Systematic reviews (with homogeneity) of randomized controlled trials 1b: Individual randomized controlled trials (with narrow confidence interval) 1c: All randomized controlled trials (or none) 2a: Systematic reviews (with homogeneity) of coho...

Highlights  Gradient-echo MRI phase contrast depends on the underlying tissue magnetic susceptibility but is orientation-dependent and non-local.  Calculating tissue magnetic susceptibility maps overcomes the orientation-dependent and non-local nature of phase contrast.  Phase and susceptibility are primarily affected by tissue composition. For example, tissues rich in ferritin (stored iron)...

We consider local minimizers of the Ginzburg-Landau energy functional ∫ 1 2 |∇u| + 1 4 (1− u)dx and prove that, if the 0 level set is included in a flat cylinder then, in the interior, it is included in a flatter cylinder. As a consequence we prove a conjecture of De Giorgi which states that level sets of global solutions of 4u = u − u such that |u| ≤ 1, ∂nu > 0, lim xn→±∞ u(x′, xn) = ±1 are hy...

magnetic tunnel junction (MTJ) devices are emerging as a possible replacement for complementary metal-oxide semiconductors for radio-frequency (RF) signal generation. Advantages include low power consumption, small device area, and large frequency tunability. This paper shows that single devices cannot achieve the necessary noise performance for RF applications. Various coupling mechanisms are ...

The renormalization group has played an important role in the physics of the second half of the twentieth century both as a conceptual and a calculational tool. In particular it provided the key ideas for the construction of a qualitative and quantitative theory of the critical point in phase transitions and started a new era in statistical mechanics. Probability theory lies at the foundation o...

The crystallization properties of phase-change memory (PCM) in the presence of thermal disturbances are investigated with a novel micro-thermal stage. It is found that the recrystallization time due to thermal disturbances significantly varies depending on how the PCM cell drifts. The longer crystallization time is obtained following additional resistance drift, which can be described by an inc...