5,943 research outputs found
catena-Poly[[[aqua(5-nitrobenzene-1,2,3-tricarboxylato-κO 1)nickel(II)]-di-μ-aqua-[diaquasodium]-di-μ-aqua] tetrahydrate]
In the title complex, {[NaNi(C9H2NO8)(H2O)7]·4H2O}n, the NiII atom has a distorted octahedral coordination, defined by five O atoms from five water molecules and one O atom from one 5-nitrobenzene-1,2,3-tricarboxylate ligand. The Na cation is coordinated by six water O atoms in an irregular trigonal-prismatic geometry. There are seven coordinated water molecules in the asymmetic unit. The Ni and Na atoms are linked by water bridges, forming infinite chains, which are connected by strong O—H⋯O hydrogen bonds involving the coordinated and uncoordinated water molecules into a three-dimensional network
Non-Abelian Quantum Hall Effect in Topological Flat Bands
Inspired by recent theoretical discovery of robust fractional topological
phases without a magnetic field, we search for the non-Abelian quantum Hall
effect (NA-QHE) in lattice models with topological flat bands (TFBs). Through
extensive numerical studies on the Haldane model with three-body hard-core
bosons loaded into a TFB, we find convincing numerical evidence of a stable
bosonic NA-QHE, with the characteristic three-fold quasi-degeneracy of
ground states on a torus, a quantized Chern number, and a robust spectrum gap.
Moreover, the spectrum for two-quasihole states also shows a finite energy gap,
with the number of states in the lower energy sector satisfying the same
counting rule as the Moore-Read Pfaffian state.Comment: 5 pages, 7 figure
Fractional Quantum Hall Effect of Hard-Core Bosons in Topological Flat Bands
Recent proposals of topological flat band (TFB) models have provided a new
route to realize the fractional quantum Hall effect (FQHE) without Landau
levels. We study hard-core bosons with short-range interactions in two
representative TFB models, one of which is the well known Haldane model (but
with different parameters). We demonstrate that FQHE states emerge with
signatures of even number of quasi-degenerate ground states on a torus and a
robust spectrum gap separating these states from higher energy spectrum. We
also establish quantum phase diagrams for the filling factor 1/2 and illustrate
quantum phase transitions to other competing symmetry-breaking phases.Comment: 4 pages, 6 figure
Gravitational conundrum? Dynamical mass segregation versus disruption of binary stars in dense stellar systems
Upon their formation, dynamically cool (collapsing) star clusters will,
within only a few million years, achieve stellar mass segregation for stars
down to a few solar masses, simply because of gravitational two-body
encounters. Since binary systems are, on average, more massive than single
stars, one would expect them to also rapidly mass segregate dynamically.
Contrary to these expectations and based on high-resolution Hubble Space
Telescope observations, we show that the compact, 15-30 Myr-old Large
Magellanic Cloud cluster NGC 1818 exhibits tantalizing hints at the >= 2 sigma
level of significance (> 3 sigma if we assume a power-law secondary-to-primary
mass-ratio distribution) of an increasing fraction of F-star binary systems
(with combined masses of 1.3-1.6 Msun) with increasing distance from the
cluster center, specifically between the inner 10 to 20" (approximately
equivalent to the cluster's core and half-mass radii) and the outer 60 to 80".
If confirmed, this will offer support of the theoretically predicted but thus
far unobserved dynamical disruption processes of the significant population of
'soft' binary systems---with relatively low binding energies compared to the
kinetic energy of their stellar members---in star clusters, which we have
access to here by virtue of the cluster's unique combination of youth and high
stellar density.Comment: Accepted for publication in The Astrophysical Journal; 19 pages in
AASTeX format; 3 figure
Maximum Estrada Index of Bicyclic Graphs
Let be a simple graph of order , let
be the eigenvalues of the
adjacency matrix of . The Esrada index of is defined as
. In this paper we determine the unique
graph with maximum Estrada index among bicyclic graphs with fixed order
Electrophysiological Correlates of Reading the Single- and Interactive-Mind
Understanding minds is the cognitive basis of successful social interaction. In everyday life, human mental activity often happens at the moment of social interaction among two or multiple persons instead of only one-person. Understanding the interactive mind of two- or multi-person is more complex and higher than understanding the single-person mind in the hierarchical structure of theory of mind. Understanding the interactive mind maybe differentiate from understanding the single mind. In order to examine the dissociative electrophysiological correlates of reading the single mind and reading the interactive mind, the 64 channels event-related potentials were recorded while 16 normal adults were observing three kinds of Chinese idioms depicted physical scenes, one-person with mental activity, and two- or multi-person with mental interaction. After the equivalent N400, in the 500- to 700-ms epoch, the mean amplitudes of late positive component (LPC) over frontal for reading the single mind and reading the interactive mind were significantly more positive than for physical representation, while there was no difference between the former two. In the 700- to 800-ms epoch, the mean amplitudes of LPC over frontal–central for reading the interactive mind were more positive than for reading the single mind and physical representation, while there was no difference between the latter two. The present study provides electrophysiological signature of the dissociations between reading the single mind and reading the interactive mind
Poly[μ2-aqua-aqua(μ3-1H-benzimidazole-5,6-dicarboxylato-κ3 N 3:O 5:O 5′)manganese(II)]
In the title complex, [Mn(C9H4N2O4)(H2O)2]n, the MnII atom is in a distorted octahedral coordination completed by one N atom from one 1H-benzimidazole-5,6-dicarboxylate ligand, two O atoms from two different 1H-benzimidazole-5,6-dicarboxylate ligands, and three O atoms from three water molecules. Two bridging water molecules and two bridging carboxylate groups from a 1H-benzimidazole-5,6-dicarboxylate ligand connect two MnII ions into a dimeric structure. In the crystal, extensive intermolecular O—H⋯O, N—H⋯O and C—H⋯O hydrogen bonding forms a three-dimensional network
Highly efficient flame retardant and smoke suppression mechanism of polypropylene nanocomposites based on clay and allylamine polyphosphate.
Fire-retarded polymer nanocomposites (FRPN) based on polypropylene with clay and allylamine polyphosphate (PP/clay-AAPP) were designed and prepared by melt mixing. Their morphological, thermal and fire-safety properties were investigated by TEM, SEM, EDS, TG, UL-94, LOI, cone-calorimeter test and TG-FTIR. The results exhibited that the LOI of PP/2 wt%clay-20wt%AAPP nanocomposites was 29.5% with V-0 rating level in UL-94 vertical testing. Significant enhancements in fire safety performance were also observed for fire-retarded PP nanocomposites from cone-calorimeter test decreasing heat release as well as smoke and toxic gases. PP/clay-AAPP nanocomposites not only provided relatively stable char layer during polymer burning, but also exhibited better fire safety performance due to the exfoliation of clay platelets. It displayed that incorporation of clay and AAPP were very efficient in increasing the fire safety of PP composites.post-print6433 K
catena-Poly[[(acetato-κO)[4-(1H-pyrazol-3-yl)pyridine-κN 1]zinc]-μ-acetato-κ2 O:O′]
In the title compound, [Zn(CH3CO2)2(C8H7N3)]n, the ZnII atom is coordinated by one N atom from a 4-(1H-pyrazol-3-yl)pyridine ligand and three O atoms from two bridging and one terminal acetate ligands, forming a distorted tetrahedral geometry. The bridging acetate ligands link the Zn atoms into a chain along [001]. N—H⋯O hydrogen bonds and π–π interactions between the pyridine and pyrazole rings [centroid–centroid distance = 3.927 (3) Å] connect the chains into a layer parallel to (011)
QT Interval Prolongation Associated with Intramuscular Ziprasidone in Chinese Patients: A Case Report and a Comprehensive Literature Review with Meta-Analysis
Intramuscular (IM) ziprasidone has been associated with QTc interval prolongations in patients with preexisting risk factors. A 23-year-old male Chinese schizophrenia patient experienced an increase of QTc interval of 83 milliseconds (ms) after receiving 20 mg IM ziprasidone (baseline and increased QT/QTc were, respectively, 384/418 and 450/501). This was rated as a probable adverse drug reaction (ADR) by the Liverpool ADR causality assessment tool. A systematic review including all types of trials reporting the effect of IM ziprasidone on the QTc interval prolongation identified 19 trials with a total of 1428 patients. Mean QTc change from baseline to end of each study was -3.7 to 12.8 ms after IM ziprasidone. Four randomized trials (3 of 4 published in Chinese) were used to calculate a meta-analysis of QTc interval prolongation which showed no significant differences between IM ziprasidone and IM haloperidol groups (risk ratio 0.49 to 4.31, 95% confidence interval 0.09 to 19.68, P = 0.06 to 0.41). However, our review included two cases of patients who experienced symptoms probably related to QTc prolongation after IM ziprasidone. Thus, careful screening and close monitoring, including baseline ECG, should be considered in patients receiving IM ziprasidone for the first time
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