Nodeless d-wave superconducting pairing due to residual antiferromagnetism in underdoped Pr2-xCexCuO4-delta

We investigate the doping dependence of the penetration depth versus temperature in electron-doped Pr(2-x)Ce(x)CuO(4-delta) using a model which assumes the uniform coexistence of (mean-field) antiferromagnetism and superconductivity. Despite the presence of a d(x2-y2) pairing gap in the underlying spectrum, we find nodeless behavior of the low-T penetration depth in the underdoped case, in accord with experimental results. As doping increases, a linear-in-T behavior of the penetration depth, characteristic of d-wave pairing, emerges as the lower magnetic band crosses the Fermi level and creates a nodal Fermi surface pocket.     

Nonlocal time-delayed feedback control of spatiotemporal patterns: controlling a network of digital phase-locked loops

Nonlinear Dynamics - Control of spatially extended systems is an important and challenging topic of research. Previous control techniques rely on local or global feedback control. In this paper,...     

Single amplifier biquad based inductor-free Chua’s circuit

The present paper reports an inductor-free realization of Chua??s circuit, which is designed by suitably cascading a single amplifier biquad based active band pass filter with a Chua??s diode. The system has been mathematically modeled with three-coupled first-order autonomous nonlinear differential equations. It has been shown through numerical simulations of the mathematical model and hardware experiments that the circuit emulates the behaviors of a classical Chua??s circuit, e.g., fixed point behavior, limit cycle oscillation, period doubling cascade, chaotic spiral attractors, chaotic double scrolls and boundary crisis. The occurrence of chaotic oscillation has been established through experimental power spectrum, and quantified with the dynamical measure like Lyapunov exponents.     

Synthesis of chiral oxa- and azacycle-fused anthraquinone derivatives

A convenient protocol for the synthesis of chiral pyran and piperidine ring-fused anthraquinone derivatives has been developed from (R)-2,3-O-cyclohexylidene-glyceraldehyde using sequential applications of enyne metathesis, Diels–Alder reaction and aromatization as key steps.     

Imide‐functionalized naphthodithiophene based donor‐acceptor conjugated polymers for solar cells

Donor‐acceptor conjugated polymers containing a new imide‐functionalized naphthodithiophene (INDT) as the acceptor unit and a 2,2'‐bithiophene with varied substituents as the donor unit have been synthesized. The bandgaps of these polymers depend strongly on the dihedral angle of the 2,2'‐bithiophene unit. The 3,3'‐dialkoxy substitution (polymers PDOR / PBOR ) leads to near planar bithiophene conformation due to the well‐known S–O short contact, while the 3,3'‐dialkyl substitution (polymer PDR ) results in significant twisting due to the steric effect. Consequently PDOR / PBOR shows the lowest bandgap of 1.82/1.85 eV while PDR has a bandgap of 2.38 eV. Bulk‐heterojunction solar cells of the polymer/fullerene blends have been fabricated. Preliminary results show that PBOR gives the best device performance with power conversion efficiencies as high as 2.45% in air without any thermal annealing treatment, indicating the promising potential of INDT‐containing conjugated polymers for efficient solar cells. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013 , 51, 3818–3828     

Enantiodivergent synthetic entry to the quinolizidine alkaloid lasubine II

Intramolecular cycloaddition of the syn- and the anti-nitrone 9 and 13 leads stereoselectively to the azabicyclic compounds 10 and 14 which may provide access to both enantiomers of the quinolizidine alkaloid lasubine II.     

Forward–Backward–Half Forward Dynamical Systems for Monotone Inclusion Problems with Application to v-GNE

Journal of Optimization Theory and Applications - In this paper, the first-order forward–backward–half forward dynamical systems associated with the inclusion problem consisting of...     

Bulk-phase thermodynamic properties and dielectric constant of ethanol: an ab initio quantum mechanical approach combined with a statistical model

Ab initio theory at the HF/6-311G(d,p) level has been used to compute the hydrogen bonding thermodynamics in bulk liquid ethanol. Inter-cluster hydrogen bonding is assumed to mimic the H-bonding in bulk ethanol. Rotation of the clusters has been neglected, but translational and vibrational motions are taken into account for calculating bulk thermodynamic parameters. Results are well in agreement with an earlier report [J. Chem. Phys. 116, 4212 (2002)]. For a more accurate dipole moment of monomer, MP2/6-311++G(d,p) calculation was done. Use of the computed thermodynamic data in a statistical model yields the Kirkwood-Frohlich correlation factor and the dielectric constant of ethanol (21.0) close to the experimental value, 24.3 at 298 K.     

Divagations about the periodic table: Boolean hypercube and quantum similarity connections

In this study, several simple aspects associated with the periodic table (PT) of the elements are commented. First, the connection of the PT with the structure of a seven-dimensional Boolean hypercube leads afterward to discuss the nature of those PT elements bearing prime atomic numbers. Second, the use of quantum similarity (QS) to obtain an alternative insight on the PT element relations will be also developed. The foundation of the second part starts admitting that any element of the PT can be attached to a schematic electronic density function, constructed with a single Gaussian function: a Gaussian atomic density function, allowing to consider the PT elements as a set of quantum objects, and permits a straightforward construction of a QS matrix. Such QS scheme can be applied to the whole PT or to any subset of it. Manipulation of the QS matrices attached to any quantum object set allows the evaluation of statistical-like values, acting as coordinates to numerically or graphically represent the chosen PT atomic element sets. © 2019 Wiley Periodicals, Inc.