Mechanism and thermochemistry of oxidation of HCl and HBr at high temperatures. The heat of formation of HO2

Using currently available thermochemical and kinetic data and estimation methods to analyze the thermochemistry and the kinetic parameters of the elementary reactions involved in the oxidation of HCl and HBr, reaction mechanisms are proposed which account for the previously reported reaction products, the rate law, and the kinetic data. For oxidation of HCl, two competitive pathways, the radical initiation by hydrogen abstraction and the fourcenter reaction pathway, were invoked to account for the observations. In the oxidation of HBr one must invoke a fast surface reaction of the type to account for the reaction.     

Cascaded dynamic eigenstates of polarization analysis for piezoelectric polarization control

We propose the cascaded dynamic eigenstates (DESs) of polarization to analyze multicomponent polarization control (PC) devices, and achieve the analytical expression of output state of polarization (SOP) as a function of voltage for piezoelectric polarization control (PPC). By measuring the DES at the output port of the device, the prestage DESs will rotate around subsequent ones. Experimental results in PPC confirm the validity of our analysis. The average error of our theoretical output SOP is 1.23 degrees, and the SOP response time is ~10 micros, which is promising to realize a quasi-open-loop high-speed PC.     

X-quasinormal subgroups

Considering two subgroups A and B of a group G and ? ≠ X ? G, we say that A is X-permutable with B if AB ^x = B ^x A for some element x ∈ X. We use this concept to give new characterizations of the classes of solvable, supersolvable, and nilpotent finite groups.     

Structure and magnetic ordering of KxH1-xNi(OH2)4[Ru2(CO3)4].zH2O

K(x)H(1-x)Ni(OH2)4[Ru2(CO3)4].zH2O is a ferrimagnet (Tc = 4.3 K) formed from the reaction of K3[Ru(II/III)2(CO3)4] and Ni(II) in water. It possesses a new 3-D network structural motif composed of linked chains and mu3-CO3 linkages to both Ru and Ni sites. Each Ni(II) bonds to four oxygens and to two [Ru2(CO3)4]3- moieties in a cis manner, and four mu3-CO3 groups from each [Ru2(CO3)4](3-) have two oxygens bonding to the Ru2 moiety, forming the typical paddle-wheel core, and trans pairs of the third CO32- oxygen axially bonded to either another Ru2 or Ni(II).     

Nonlinear delay difference equations for housing dynamics assuming heterogeneous backward-looking expectations

China's first interest rate hike during the last decade, aiming to cool down the seemingly overheated real estate market, had aroused more caution on housing market. This paper aims to analyze the housing price dynamics after an unanticipated economic shock, which was believed to have similar properties with the back ward- looking expectation models. The analysis of the housing price dynamics is based on the cobweb model with a simple user cost affected demand and a stock-flow supply assumption. Several nth-order delay rational difference equations are set up to illustrate the properties of housing dynamics phenomena, such as the equilibrium or oscillations, overshoot or undershoot and convergent or divergent, for a kind of heterogeneous backward-looking expectation models. The results show that demand elasticity is less than supply elasticity is not a necessary condition for the occurrence of oscillation. The housing price dynamics will vary substantially with the heterogeneous backward-looking expectation assumption and some other endogenous factors.     

All-optical XOR logic gate operating on inputs with different modulation formats

An all-optical logic gate which can perform logic exclusive-OR (XOR) between an intensity modulated signal and a phase modulated one, is proposed and numerically investigated. The working principle of this logic gate is based on cross phase modulation in a highly nonlinear fiber.     

On p-Regular G-Conjugacy Classes and the p-Structure of Normal Subgroups

Let N be a p-solvable normal subgroup of a group G such that N contains a noncentral Sylow r (≠ p)-subgroup R of G. It is proved that the p-complements of N are nilpotent if |x ^G |=1 or m for every p-regular element x of N whose order is divisible by at most two distinct primes. Our result, therefore, gives some information concerning the nilpotence of some kind of subgroups of a group G.     

Triply resonant Raman scattering in perovskite semiconductor CsSnI3

We report on the first‐order and second‐order Raman scattering (SORS) by longitudinal optical (LO) phonons in perovskite semiconductor CsSnI₃. The intensity of SORS is stronger than that of the first order. The spectral line shape of SORS is asymmetric and much broader than that of the first order. It is identified that the strong SORS intensity is attributable to the triply enhanced resonant process, which is naturally implemented through the peculiar band structure of this semiconductor compound having two adjacent parallel conduction bands with a separation close to the energy of two LO phonons. Copyright © 2012 John Wiley & Sons, Ltd.