Read by QxMD icon Read

Phase separation

Zikuan Chen, Jennifer Robinson, Vince Calhoun
PURPOSE: To computationally separate dynamic brain functional BOLD responses from static background in a brain functional activity for forward fMRI signal analysis and inverse mapping. METHODS: A brain functional activity is represented in terms of magnetic source by a perturbation model: χ = χ0 +δχ, with δχ for BOLD magnetic perturbations and χ0 for background. A brain fMRI experiment produces a timeseries of complex-valued images (T2* images), whereby we extract the BOLD phase signals (denoted by δP) by a complex division...
2018: PloS One
Oscar Viyuela, Liang Fu, Miguel Angel Martin-Delgado
We study the phase diagram and edge states of a two-dimensional p-wave superconductor with long-range hopping and pairing amplitudes. New topological phases and quasiparticles different from the usual short-range model are obtained. When both hopping and pairing terms decay with the same exponent, one of the topological chiral phases with propagating Majorana edge states gets significantly enhanced by long-range couplings. On the other hand, when the long-range pairing amplitude decays more slowly than the hopping, we discover new topological phases where propagating Majorana fermions at each edge pair nonlocally and become gapped even in the thermodynamic limit...
January 5, 2018: Physical Review Letters
Insun Jo, Hao Deng, Yang Liu, L N Pfeiffer, K W West, K W Baldwin, M Shayegan
We study a bilayer GaAs hole system that hosts two distinct many-body phases at low temperatures and high perpendicular magnetic fields. The higher-density (top) layer develops a Fermi sea of composite fermions (CFs) in its half-filled lowest Landau level, while the lower-density (bottom) layer forms a Wigner crystal (WC) as its filling becomes very small. Owing to the interlayer interaction, the CFs in the top layer feel the periodic Coulomb potential of the WC in the bottom layer. We measure the magnetoresistance of the top layer while changing the bottom-layer density...
January 5, 2018: Physical Review Letters
Kunpeng Cui, Zhe Ma, Nan Tian, Fengmei Su, Dong Liu, Liangbin Li
Flow-induced crystallization (FIC) is a typical nonequilibrium phase transition and a core industry subject for the largest group of commercially useful polymeric materials: semicrystalline polymers. A fundamental understanding of FIC can benefit the research of nonequilibrium ordering in matter systems and help to tailor the ultimate properties of polymeric materials. Concerning the crystallization process, flow can accelerate the kinetics by orders of magnitude and induce the formation of oriented crystallites like shish-kebab, which are associated with the major influences of flow on nucleation, that is, raised nucleation density and oriented nuclei...
January 19, 2018: Chemical Reviews
Mingjun Huang, Kan Yue, Jiahao Huang, Chang Liu, Zhe Zhou, Jing Wang, Kan Wu, Wenpeng Shan, An-Chang Shi, Stephen Z D Cheng
This work reports the molecular design, synthesis, and systematic study on the bulk self-assembly behaviors of three series of polyhedral oligomeric silsesquioxanes (POSS)-based multi-headed giant surfactants XDPOSS-PSn (X = 2, 3 and 4), which are composed of two, three or four hydrophilic hydroxyl-group functionalized DPOSS cages attached via one junction point to a hydrophobic polystyrene (PS) chain. These series of hybrid polymeric amphiphiles with precisely defined chemical structure and controllable molecular architecture are synthesized by the sequential usage of "click" reactions...
January 19, 2018: ACS Nano
Claire C Berton-Carabin, Leonard Sagis, Karin Schroën
Emulsions, i.e., the dispersion of liquid droplets in a nonmiscible liquid phase, are overwhelmingly present in food products. In such systems, both liquid phases (generally, oil and water) are separated by a narrow region, the oil-water interface. Despite the fact that this interface is very thin (in the nanometer range), it represents a large surface area and controls to a great extent the physicochemical stability of emulsions. This review provides an overview of the aspects that govern the composition, structure, and mechanical properties of interfaces in food emulsions, taking into account the complexity of such systems (presence of numerous surface-active molecules, influence of processing steps, and dynamic evolution due to chemical changes)...
January 18, 2018: Annual Review of Food Science and Technology
Sarah H Ward, Troy Blackburn, Darin A Padua, Laura E Stanley, Matthew S Harkey, Brittney A Luc-Harkey, Brian G Pietrosimone
CONTEXT:   Aberrant biomechanics may affect force attenuation at the knee during dynamic activities, potentially increasing the risk of sustaining a knee injury or hastening the development of osteoarthritis after anterior cruciate ligament reconstruction (ACLR). Impaired quadriceps neuromuscular function has been hypothesized to influence the development of aberrant biomechanics. OBJECTIVE:   To determine the association between quadriceps neuromuscular function (strength, voluntary activation, and spinal-reflex and corticomotor excitability) and sagittal-plane knee biomechanics during jump landings in individuals with ACLR...
January 19, 2018: Journal of Athletic Training
Xuewu Ou, Yanzi Yu, Ruizhe Wu, Abhishek Tyagi, Minghao Zhuang, Yao Ding, Irfan Haider Abidi, Heng-An Wu, Feng-Chao Wang, Zhengtang Luo
"Shuttle effect" of lithium polysulfides (LiPS) leads to poor performance and short cycle life of Li-S battery, thus limiting their practical application. We demonstrate here that after coating polypropylene (PP) separator with a continuous monolayer graphene, the "shuttle effect" can be significantly suppressed by limiting the passage of long chain LiPS. The graphene/PP separator can be further modified by sealing the big holes or pores on graphene with in situ polymerized nylon-66, via an interfacial polymerization reaction between diamine and adipoyl chloride supplied by the aqueous and oil phase, respectively from each side of the membrane...
January 19, 2018: ACS Applied Materials & Interfaces
Marina Russo, Chiara Fanali, Giusy Tripodo, Paola Dugo, Rosario Muleo, Laura Dugo, Laura De Gara, Luigi Mondello
The analysis of pomegranate phenolic compounds belonging to different classes in different fruit parts was performed by high-performance liquid chromatography coupled with photodiode array and mass spectrometry detection. Two different separation methods were optimized for the analysis of anthocyanins and hydrolyzable tannins along with phenolic acids and flavonoids. Two C18 columns, core-shell and fully porous particle stationary phases, were used. The parameters for separation of phenolic compounds were optimized considering chromatographic resolution and analysis time...
January 19, 2018: Analytical and Bioanalytical Chemistry
Johannes Clemens Godt, Torsten Eken, Anselm Schulz, Cathrine K Johansen, Anette Aarsnes, Johann Baptist Dormagen
Background Split-bolus computed tomography (CT) is a recent development in trauma imaging. Instead of multiple scans in different contrast phases after a single contrast bolus, split-bolus protocols consist of one single scan of the thorax and abdomen after two or three contrast injections at different points of time. Purpose To evaluate and compare image quality and injury findings of a new triple-split-bolus CT (TS-CT) protocol of thorax and abdomen with those of a portal venous phase CT (PV-CT) in the same patient group...
January 1, 2018: Acta Radiologica
Hongcai He, Zhuolin Jiang, Zhaoling He, Tao Liu, Enzhu Li, Bao-Wen Li
An excellent ternary composite photocatalyst consisting of silver orthophosphate (Ag3PO4), attapulgite (ATP), and TiO2 was synthesized, in which heterojunction was formed between dissimilar semiconductors to promote the separation of photo-generated charges. The ATP/TiO2/Ag3PO4 composite was characterized by SEM, XRD, and UV-vis diffuse reflectance spectroscopy. The co-deposition of Ag3PO4 and TiO2 nanoparticles onto the surface of ATP forms a lath-particle structure. Compared with composite photocatalysts consisting of two phases, ATP/TiO2/Ag3PO4 ternary composite exhibits greatly improved photocatalytic activity for degradation of rhodamine B under simulated solar irradiation...
January 18, 2018: Nanoscale Research Letters
Tong Li, Junhui He, Yue Zhang, Lin Yao, Tingting Ren, Binbin Jin
Unprecedented in situ formation of artificial moth-eye structure is demonstrated by spontaneous nano-phase separation of a silica-based system on substrate. The moth-eye thin film with a homogenously distributed nipples array shows broadband antireflection functionalities. The mechanism of nano-phase separation is unveiled as spinodal decomposition by chemical freezing method and thermodynamic analysis. The current method may provide a new avenue to ready fabrication of patterned nanostructures toward a variety of applications...
January 18, 2018: Scientific Reports
D Smith, M A Hakeem, P Parisiades, H E Maynard-Casely, D Foster, D Eden, D J Bull, A R L Marshall, A M Adawi, R Howie, A Sapelkin, V V Brazhkin, J E Proctor
We report experimental evidence for a crossover between a liquidlike state and a gaslike state in fluid methane (CH_{4}). This crossover is observed in all of our experiments, up to a temperature of 397 K, 2.1 times the critical temperature of methane. The crossover has been characterized with both Raman spectroscopy and x-ray diffraction in a number of separate experiments, and confirmed to be reversible. We associate this crossover with the Frenkel line-a recently hypothesized crossover in dynamic properties of fluids extending to arbitrarily high pressure and temperature, dividing the phase diagram into separate regions where the fluid possesses liquidlike and gaslike properties...
November 2017: Physical Review. E
Horacio V Guzman, Christoph Junghans, Kurt Kremer, Torsten Stuehn
Multiscale and inhomogeneous molecular systems are challenging topics in the field of molecular simulation. In particular, modeling biological systems in the context of multiscale simulations and exploring material properties are driving a permanent development of new simulation methods and optimization algorithms. In computational terms, those methods require parallelization schemes that make a productive use of computational resources for each simulation and from its genesis. Here, we introduce the heterogeneous domain decomposition approach, which is a combination of an heterogeneity-sensitive spatial domain decomposition with an a priori rearrangement of subdomain walls...
November 2017: Physical Review. E
J Toruniewska, K Kułakowski, K Suchecki, J A Hołyst
We consider the process of reaching the final state in the coevolving voter model. There is a coevolution of state dynamics, where a node can copy a state from a random neighbor with probabilty 1-p and link dynamics, where a node can rewire its link to another node of the same state with probability p. That exhibits an absorbing transition to a frozen phase above a critical value of rewiring probability. Our analytical and numerical studies show that in the active phase mean values of magnetization of nodes n and links m tend to the same value that depends on initial conditions...
October 2017: Physical Review. E
Daniel Stopper, Roland Roth
Using classical density functional theory, we investigate systems exhibiting interactions where a short-range anisotropic attractive force competes with a long-range spherically symmetric repulsive force. The former is modelled within Wertheim's first-order perturbation theory for patchy particles, and the repulsive part is assumed to be a Yukawa potential which is taken into account via a mean-field approximation. From previous studies of systems with spherically symmetric competing interactions, it is well known that such systems can exhibit stable bulk cluster phases (microphase separation) provided that the repulsion is sufficiently weak compared to the attraction...
October 2017: Physical Review. E
K Choi, Deokjae Lee, Y S Cho, J C Thiele, H J Herrmann, B Kahng
Recently, a hybrid percolation transition (HPT) that exhibits both a discontinuous transition and critical behavior at the same transition point has been observed in diverse complex systems. While the HPT induced by avalanche dynamics has been studied extensively, the HPT induced by cluster merging dynamics (HPT-CMD) has received little attention. Here, we aim to develop a theoretical framework for the HPT-CMD. We find that two correlation-length exponents are necessary for characterizing the giant cluster and finite clusters separately...
October 2017: Physical Review. E
Arvin Vaghela, Paulo I C Teixeira, Eugene M Terentjev
We investigate the isotropic, uniaxial nematic and biaxial nematic phases, and the transitions between them, for a model lyotropic mixture of flexible molecules consisting of two rigid rods connected by a spacer with variable bending stiffness. We apply density-functional theory within the Onsager approximation to describe strictly excluded-volume interactions in this athermal model and to self-consistently find the orientational order parameters dictated by its complex symmetry, as functions of the density...
October 2017: Physical Review. E
T Cary, R R P Singh, R T Scalettar
We explore the phase diagram of Ising spins on one-dimensional chains that criss-cross in two perpendicular directions and that are connected by interchain couplings. This system is of interest as a simpler, classical analog of a quantum Hamiltonian that has been proposed as a model of magnetic behavior in Nb_{12}O_{29} and also, conceptually, as a geometry that is intermediate between one and two dimensions. Using mean-field theory as well as Metropolis Monte Carlo and Wang-Landau simulations, we locate quantitatively the boundaries of four ordered phases...
October 2017: Physical Review. E
Xiang Fan, P H Diamond, L Chacón
We study the evolution of the concentration field in a single eddy in the two-dimensional (2D) Cahn-Hilliard system to better understand scalar mixing processes in that system. This study extends investigations of the classic studies of flux expulsion in 2D magnetohydrodynamics and homogenization of potential vorticity in 2D fluids. Simulation results show that there are three stages in the evolution: (A) formation of a "jelly roll" pattern, for which the concentration field is constant along spirals; (B) a change in isoconcentration contour topology; and (C) formation of a target pattern, for which the isoconcentration contours follow concentric annuli...
October 2017: Physical Review. E
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"