Narrow Results

Condensation occurs when the air temperature drops to its dew point, causing water vapors in the air to cool, lose kinetic energy, and transform into liquid droplets. This process is influenced by the relative humidity and temperature fluctuations, where lower temperatures reduce the air’s capacity to hold water vapor, resulting in the formation of liquid water droplets on cooler surfaces. The condensation process is fundamental to the operation of fog harvesting systems, where specialized meshes capture the transformed water droplets. However, the behavior of droplets attached to meshes under background airflow is not well understood. Consequently, controlling the motion and merging of these droplets with neighboring ones poses a significant challenge. In this study, for fog airflow, it is demonstrated that droplets on parallel meshes can aerodynamically interact with both downstream and upstream neighbors at different temperatures. These interactions lead to diverse behaviors, including alignment, coalescence, and repulsion. This study explores the key factors influencing the efficiency of material and design used for fog harvesting systems, and environmental conditions such as fog density and wind speed. The dynamical model includes the single-phase transport equation along with the $k-\mathrm{\Omega }$ SST (Shear Stress Transport (SST) k-omega) a subclass of RAS (Reynolds-Averaged Simulation) model. The computational analysis of fog harvesting mesh for water collection is performed in OpenFOAM (Open-source Field Operation And Manipulation). The Finite Volume Method (FVM) is employed for solution of the model to check the efficiency and effectiveness of fog harvesting computational designs. Using OpenFOAM, condensation, alignment and merging behaviors based on the interactions between wakes and droplets are visualized. The computational design enhances the surface area available for fog capture, thereby increasing the droplets collection efficiency and resulting in a higher yield of liquid water. The computational results obtained in this study can lead to more sustainable and efficient fog water collectors.

The synthesis of open-chain, tetrapyrrolic 2,2'-bisdipyrrin ligands was investigated, starting from a variety of different pyrrolic and 2,2'-bipyrrolic precursors. Four important observations were made: (1) The solubility of 2,2'-bisdipyrrins can easily be tuned through the peripheral substituent pattern, allowing the aimed preparation of both well-soluble and hardly soluble tetrapyrroles. (2) meso-Arylsubstituted 2,2'-bisdipyrrins are easily available from respective p- and m-, but not o-functionalized dibenzoyl bipyrroles due to sterical effects. (3) Unsymmetric derivatives can be obtained by the stepwise acylation of 2,2'-bipyrroles and concomitant condensation reactions, using the new 5-benzoyl-3,3',4,4'-tetraethyl-2,2'-bipyrrole as the key intermediate. (4) meta-Nitrophenyl groups in the periphery of 2,2'-bisdipyrrins can be reduced to aminophenyl groups and further derivatized in analogy to a reaction cascade used in porphyrin chemistry, yielding superstructured 2,2'-bisdipyrrins. The synthetic schemes developed open the way for a large variety of tailor-made 2,2'-bisdipyrrin ligands.

We present a linear agent based model on brand competition. Each agent belongs to one of the two brands and interacts with its nearest neighbors. In the process the agent can decide to change to the other brand if the move is beneficial. The numerical simulations show that the systems always condenses into a state when all agents belong to a single brand. We study the condensation times for different parameters of the model and the influence of different mechanisms to avoid condensation, like anti monopoly rules and brand fidelity.

The combination of large eddy simulation (LES) and newly proposed Taylor-series expansion method of moments (TEMOM) is performed for simulating particulate matters emitted from vehicle engine tailpipe. The momentum, heat and mass transfer, binary homogeneous nucleation, Brownian coagulation, Brownian and turbulent diffusion, condensation and thermophoresis are simultaneously taken into account. Good agreements between the experimental and simulated results with respect to the pollutant dispersion are obtained. Compared to other published methods, the present TEMOM requires the least computational time with much accuracy for predicting nanoparticle dynamics. The instantaneous results show that large eddies dominate the evolution of particulate dynamics as exhaust develops, while binary homogeneous sulfuric-water nucleation mainly appears at the interface between the exhaust and ambient cool gases. The increasing of fuel sulfur content and relative humidity or the decreasing of environment temperature leads to an increase in particulate product rate, while volume-averaged particle diameter increases with increasing fuel sulfur content and environment temperature. The variation of geometric standard deviation suggests the nucleated particles eventually approach the asymptotic distribution in the dilution atmosphere, and this distribution is independent of the fuel sulfur content. The variance of upstream turbulence intensity significantly affects the evolution of particulate matters inside the plume.

An agent-based model was built representing an economic environment in which m brands are competing for a product market. These agents represent companies that interact within a social network in which a certain agent persuades others to update or shift their brands; the brands of the products they are using. Decision rules were established that caused each agent to react according to the economic benefits it would receive; they updated/shifted only if it was beneficial. Each agent can have only one of the m possible brands, and she can interact with its two nearest neighbors and another set of agents which are chosen according to a particular set of rules in the network topology. An absorbing state was always reached in which a single brand monopolized the network (known as condensation). The condensation time varied as a function of model parameters is studied including an analysis of brand competition using different networks.

A numerical algorithm is used to solve the bare and the effective potential for the scalar ϕ⁴ model in the local potential approximation. An approximate dynamical Maxwell-cut is found which reveals itself in the degeneracy of the action for modes at some scale. This result indicates that the potential develop singular field dependence as far as one can see it by an algorithm of limited numerical accuracy.

We review recent interactions between mathematical theory of two-dimensional topological order and operator algebras, particularly the Jones theory of subfactors. The role of representation theory in terms of tensor categories is emphasized. Connections to two-dimensional conformal field theory are also presented. In particular, we discuss anyon condensation, gapped domain walls and matrix product operators in terms of operator algebras.

When saturated vapor passes over a colder substrate, liquid drops nucleate and grow by coalescence with surrounding drops. Typically speaking, nucleation and growth rates of water droplets are faster on a hydrophilic surface than on a hydrophobic surface. However, heat transfer efficiency degrades once surface becomes filmwise condensation. In this paper, vapor condensing on a gradient surface to prevent filmwise condensation is studied. New gradient surfaces are fabricated. It is demonstrated that 10% increase of condensation heat flux can be achieved on a silicon wafer with C = 1 mm gradient surface. The main mechanism for heat transfer enhancement is found to be that drops condensing on C = 1 mm gradient surface begin to move at a much smaller size compared with those on silicon wafer without modification.

This paper deals with the analysis of the steady flow of a semi-infinite expanse of rarefied gas bounded by its plane condensed phase by the methods of the discrete kinetic theory. The existence of the solutions of the corresponding boundary value problem is discussed. The relations among the parameters of the flow near the condensed phase and at infinity required for the existence of solutions are established. The problem of condensation of a vapor gas on its own condensed phase is then solved analytically for a particular discrete model and remarkable features of the flow are analyzed.

We analytically describe the properties of the s-wave holographic superconductor with the exponential nonlinear electrodynamics in the Lifshitz black hole background in four-dimensions. Employing an assumption the scalar and gauge fields backreact on the background geometry, we calculate the critical temperature as well as the condensation operator. Based on Sturm–Liouville method, we show that the critical temperature decreases with increasing exponential nonlinear electrodynamics and Lifshitz dynamical exponent, $z$, indicating that condensation becomes difficult. Also we find that the effects of backreaction has a more important role on the critical temperature and condensation operator in small values of Lifshitz dynamical exponent, while $z$ is around one. In addition, the properties of the upper critical magnetic field in Lifshitz black hole background using Sturm–Liouville approach is investigated to describe the phase diagram of the corresponding holographic superconductor in the probe limit. We observe that the critical magnetic field decreases with increasing Lifshitz dynamical exponent, $z$, and it goes to zero at critical temperature, independent of the Lifshitz dynamical exponent, $z$.

Gravity-induced condensation takes the form of momentum alignment in an ensemble of identical particles. Use is made of a one-dimensional Ising model to calculate the alignment per particle and the correlation length as a function of the temperature. These parameters indicate that momentum alignment is possible in the proximity of some astrophysical objects and in Earth, or near Earth laboratories. Momenta oscillations behave as known spin oscillations and obey identical dispersion relations.

We comment briefly on a possible energy source from graphene, arising out of the anomalous behavior of a beam of protons in it.

Understanding the fundamental mechanisms of vapor condensation on rough surfaces is crucial to a wide range of industrial applications. A hybrid thermal lattice Boltzmann model of the condensation heat transfer process on downward-facing rough surfaces characterized by the Cantor fractal is developed and numerically analyzed to investigate the condensation phase change behaviors on rough hydrophobic and hydrophilic surfaces. The dynamic behaviors of vapor condensation, including the evolutions of vapor–liquid interface, heat flux, condensate mass, and temperature distribution, on the hydrophilic and hydrophobic rough surfaces are presented and compared with corresponding smooth surfaces. The results indicate that the rough surface preferred a filmwise condensation under hydrophilic conditions but a hybrid dropwise–filmwise condensation under hydrophobic conditions. On the rough hydrophobic surface, the liquid film can rapidly adsorb droplets, maintaining a high-efficiency dropwise condensation. The absorption of droplets accelerates the liquid film growth and detachment process on the rough hydrophobic surface, which reduces the time-averaged thermal resistance of the filmwise region. These two behaviors together enhance condensation heat transfer on the downward-facing rough hydrophobic surface. Besides, stable dropwise condensation could also be formed on smooth hydrophilic surfaces and has better heat transfer performance than corresponding hydrophobic surfaces under the same heat transfer condition.

In this paper, we explore the dynamics of quantum correlations in an isolated physical quantum under the influence of intrinsic coherence. We characterize the quantum correlations in the hybrid system using the granular model to investigate the amount of coherent-chaotic fractions, and we particularly use the spherical droplets to measure the specific correlations. Likewise, we examine the effect of coherence on the source evolution of these quantifiers within engineering applications. In particular, the behavior of the multiparticle correlations in terms of the system parameters and the coherence rate is investigated and analyzed in detail to explore the source intrinsic dimensions. We found that the correlations with genuine interferences behave slightly unsymmetrical for identical parameters characterizing the considered complex system and that the genuine correlations are more meaningful than primary interference which probed the chaotic peculiarities against the coherence phenomena. Our results also show that the robustness of quantum correlations can be modulated by adjusting the coherent rate, source physical properties and the initial conditions.

We establish natural criteria under which normally iterable premice are iterable for stacks of normal trees. Let $\mathrm{\Omega }$ be a regular uncountable cardinal. Let $m<\omega$ and $M$ be an $m$-sound premouse and $\mathrm{\Sigma }$ be an $(m,\mathrm{\Omega }+1)$-iteration strategy for $M$ (roughly, a normal $(\mathrm{\Omega }+1)$-strategy). We define a natural condensation property for iteration strategies, inflation condensation. We show that if $\mathrm{\Sigma }$ has inflation condensation then $M$ is ${(m,\mathrm{\Omega },\mathrm{\Omega }+1)}^{\ast }$-iterable (roughly, $M$ is iterable for length $\le \mathrm{\Omega }$ stacks of normal trees each of length $<\mathrm{\Omega }$), and moreover, we define a specific such strategy ${\mathrm{\Sigma }}^{\mathrm{\text{st}}}$ and a reduction of stacks via ${\mathrm{\Sigma }}^{\mathrm{\text{st}}}$ to normal trees via $\mathrm{\Sigma }$. If $\mathrm{\Sigma }$ has the Dodd-Jensen property and $\mathrm{\text{card}}(M)<\mathrm{\Omega }$ then $\mathrm{\Sigma }$ has inflation condensation. We also apply some of the techniques developed to prove that if $\mathrm{\Sigma }$ has strong hull condensation (introduced independently by John Steel), and $G$ is $V$-generic for an $\mathrm{\Omega }$-cc forcing, then $\mathrm{\Sigma }$ extends to an $(m,\mathrm{\Omega }+1)$-strategy ${\mathrm{\Sigma }}^{+}$ for $M$ with strong hull condensation, in the sense of $V[G]$. Moreover, this extension is unique. We deduce that if $G$ is $V$-generic for a ccc forcing then $V$ and $V[G]$ have the same $\omega$-sound, $(\omega ,\mathrm{\Omega }+1)$-iterable premice which project to $\omega$.

A sensitive colorimetric L-chemosensor 1,3-dimethyl-5-(thien-2-ylmethylene)-pyrimidine-2,4,6-(1$H,3H,5H)$-trione was developed by Knoevenagel combination of barbituric acid with thiophene aldehyde chelating moiety. The sensor displayed a high colorimetric Cu(II)X₂ response; a dramatic methanol color change was recorded depending on anion type ($X={\mathrm{\text{Br}}}^{-1}$, Cl${}^{-1}$, ClO${}_4^{-1}$, NO${}_3^{-1}$, OAc${}^{-1}$, and SO${}_4^{-2})$. Off-on-off decolorized halochromism of the L-chemosensor/CuBr₂ was recorded in an acidic medium. The structure of the L-chemosensor was confirmed by single-crystal X-ray diffraction, elemental analysis, and molecular spectroscopic tools such as UV–Vis, Fourier transform infra-red, ¹H, and ${}^{13}$C nuclear magnetic resonance (NMR) spectroscopy. The thermal stability of the L-chemosensor was experimentally evaluated by thermogravimetric analysis. The structural optimized parameters of the ligand matched the crystallographic data, and the intermolecular forces were computed by Hirshfeld surface analysis. Electronic absorption in several solvents and ¹H NMR were correlated with the computed spectra in the gaseous state. The HOMO/LUMO, global reactivity descriptor quantum parameters, Mulliken charge population, and molecular electrostatic potential of the L-chemosensor were also computed.

This paper describes the application of discrete wavelet transforms to the analysis of condensation jets in order to clarify the associated fluid and heat transfer phenomena. An experimentally-obtained, two-dimensional image of the condensation particle density around the jet was decomposed into 7 levels of resolution with their respective wavelengths. Based on the known physical characteristics of turbulent flow around the jet, levels 0 and 1 were shown to represent the large-scale components of the condensation particle density and the higher levels represent the small-scale components. From the wavelet-analyzed images, the width of the condensation zone was obtained and this compared well with the width inferred from temperature measurements. Thus, the method was verified and also provided data not available experimentally.

In this paper, an unsteady preconditioning formulation for multi-phase flows with arbitrary equation of state based on the approximated Riemann solver is developed for multi-phase flows at all speed. This paper considers a homogeneous two-phase multi-equation mixture model with the assumption of kinematics and thermodynamics equilibriums. The thermodynamics behaviors of liquid phase, vapor phase and their phase transitional process are described by a temperature-dependent hybrid equation of state. Benchmark test cases, including one-dimensional (1D) condensation shock in the cavitated nozzle and two-dimensional (2D) cavitated blunt body problem, demonstrate accurate capturing of interfaces, shock waves and cavitation zones.

In this review we show how K-theory classifies RR-charges in type II string theory and how the inclusion of the B-field modifies the general structure leading to the twisted K-groups. Our main purpose is to give an expository account of the physical relevance of K-theory. To do that, we consider different points of view: processes of tachyon condensation, cancellation of global anomalies and gauge fixings. As a field to test the proposals of K-theory, we concentrate on the study of the D6-brane, now seen as a non-abelian monopole.

Following our earlier work on the perturbative thermodynamic geometry of nonextensive quantum and classical gases [H. Mohammadzadeh, F. Adli and S. Nouri, Phys. Rev. E94 (2016) 062118], we study $q$-generalized Bose–Einstein, Fermi–Dirac and classical statistics nonperturbatively. We define $q$-generalized polylogarithm functions and evaluate thermodynamics quantities such as internal energy and particle number. We construct the thermodynamic geometry of nonextensive Bose (Fermi) ideal gas and show that the thermodynamic curvature is positive(negative) in full physical range as the same as ordinary statistics. Also, we show that the thermodynamic geometry of nonextensive ideal classical gas is flat, similar to the ordinary one. Therefore, the nonextensive parameter does not change the nature of intrinsic statistical interactions. We argue that the nonextensive boson gas might be more stable than the boson gas due to conjectural interpretation of thermodynamic curvature. In the following, we extract the singular points of thermodynamic curvature of nonextensive Bose gas and relate it to the condensation. We evaluate some thermodynamic quantities such as heat capacities, compressibility and $q$-dependent phase transition temperature. We show that the heat capacity is not differentiable at critical temperature, $T_c^q$ which is reduced by increasing nonextensive parameter $q$. Moreover, the critical temperature and possibility of condensation is investigated for different values of nonextensive parameter in various dimensions.