Using first-principles density functional theory (DFT) hybrid functional calculations, we demonstrate the formation of a quantum spin Hall (QSH) state on a Ge(111) surface. We show that a 1/3 monolayer (ML) Cl-covered Ge(111) surface offers an ideal template for metal, such as Bi, deposition into a stable hexagonal overlayer 2D lattice, which we refer to as Bi@Cl-Ge(111). The band structure and...

BaBiOa is the parent compound of the new class of high Tc superconductors that contain no copper. By partially replacing Ba with K (or Bi with Pb) B a!_xK xBi0 3 becomes superconducting in a small range of x. The undoped material is a semiconductor in which the perovskite structure is unstable with re­ spect to a breathing-like distortion (Fig. 1) of the oxy­ gen octahedron (Bi disproportionate...

Three isostructural coordination networks of Ce, Pr, and Nd nitrate with 4,4'-bi-pyridine N,N'-dioxide (bpydo) are reported, namely poly[[tris-(nitrato-κ(2) O,O')cerium(III)]-bis-(μ2-4,4'-bi-pyridine N,N'-dioxide-κ(2) N:N')], [Ce(NO3)3(C10H8N2O2)2], poly[[tris-(nitrato-κ(2) O,O')praeseodymium(III)]-bis-(μ2-4,4'-bi-pyridine N,N'-dioxide-κ(2) N:N')], [Pr(NO3)3(C10H8N2O2)2], and poly[[tris(nitrato...

Resistive Random-Access Memory Devices Neuromorphic devices are essential for beyond von-Neumann computing and Random Access Memories (RRAMs) the backbone it. In article number 2200744, Chandra Prakash colleagues show RRAM characteristics in a Bi12FeO20 system first time, together with negative differential resistance (NDR) write once read many (WORM) like simultaneously. It is hoped this could...

A simple and low computational complexity system for bispeaker speech separation is proposed in this paper. The system is constructed of a voice activity classification (VAC) module and an adaptive bi-beamformer module for speech separation using a microphone array. The first module identifies active speaker(s) and allows the system to control the adaptation of the second module automatically. ...

Let (f1, . . . , fs) be a polynomial family in Q[X1, . . . , Xn] (with s 6 n− 1) of degree bounded by D. Suppose that 〈f1, . . . , fs〉 generates a radical ideal, and defines a smooth algebraic variety V ⊂ Cn. Consider a projection π : Cn → C. We prove that the degree of the critical locus of π restricted to V is bounded by Ds(D−1)n−s ( n n−s ) . This result is obtained in two steps. First the c...

In the title compound, [Fe(C12H12N2)(H2O)4]SO4, the central Fe(II) ion is coordinated by two N atoms from the 5,5'-dimethyl-2,2'-bi-pyridine ligand and four water O atoms in a distorted octa-hedral geometry. The Fe-O coordination bond lengths vary from 2.080 (3) to 2.110 (3) Å, while the two Fe-N coordination bonds have practically identical lengths [2.175 (3) and 2.177 (3) Å]. The chelating N-...

Let S be a set of n ideals of a commutative ring A and let Geven (respectively Godd) denote the product of all the sums of even (respectively odd) number of ideals of S. If n ≤ 6 the product of Geven and the intersection of all ideals of S is included in Godd. In the case A is an Noetherian integral domain, this inclusion is replaced by equality if and only if A is a Dedekind domain.

The concept of a 0-distributive poset is introduced. It is shown that a section semicomplemented poset is distributive if and only if it is 0-distributive. It is also proved that every pseudocomplemented poset is 0-distributive. Further, 0-distributive posets are characterized in terms of their ideal lattices.