B1-to-B2 structural transitions in rock salt intergrowth structures

The rock salt (B1) structure of binary oxides or chalcogenides transforms to the CsCl (B2) structure under high pressure, with critical pressures P(s) depending on the cation to anion size ratio (R(c)/R(a)). We investigated structural changes of A(2)MO(3) (A = Sr, Ca; M = Cu, Pd) comprising alternate 7-fold B1 AO blocks and corner-shared MO(2) square-planar chains under pressure. All of the examined compounds exhibit a structural transition at P(s) = 29-41 GPa involving a change in the A-site geometry to an 8-fold B2 coordination. This observation demonstrates, together with the high pressure study on the structurally related Sr(3)Fe(2)O(5), that the B1-to-B2 transition generally occurs in these intergrowth structures. An empirical relation of P(s) and the R(c)/R(a) ratio for the binary system holds well for the intergrowth structure also, which means that P(s) is predominantly determined by the rock salt blocks. However, a large deviation from the relation is found in LaSrNiO(3.4), where oxygen atoms partially occupy the apical site of the MO(4) square plane. We predict furthermore the occurrence of the same structural transition for Ruddlesden-Popper-type layered perovskite oxides (AO)(AMO(3))(n), under higher pressures. For investigating the effect on the physical properties, an electrical resistivity of Sr(2)CuO(3) is studied.     

Photodissociation investigation of doubly charged ethanol clusters induced by inner-shell electron ionization

Fragmentation of doubly charged ethanol clusters [(C(2)H(5)OH)(n)] following the O 1s ionization has been investigated by means of the photoelectron-photoion-photoion coincidence (PEPIPICO) method. The dominant fission channel of (C(2)H(5)OH)(n)(2+) was the formation of protonated cluster ion pairs [H(C(2)H(5)OH)(l)(+)/H(C(2)H(5)OH)(m)(+)]. The fragmentation mechanisms of these ion pairs were discussed based on the analysis of the PEPIPICO contour shape. It was clarified that the prominent fragmentation channel was a secondary decay mechanism, where neutral evaporation occurs after charge separation. On the other hand, the formation of small fragment ions was suppressed, excluding the formation of certain specific fragments (H(3)O(+), C(2)H(5)(+)/COH(+), and C(2)H(4)OH(+)). The formation of small fragment ions was suppressed due to the cooling effect caused by the neutral evaporation and the decrease in the electrostatic repulsive force caused by charge separation.     

Huangqiyenins G – J,Four New 9,10‐Secocycloartane (=9,19‐Cyclo‐9,10‐secolanostane) Triterpenoidal Saponins from Astragalus membranaceus Bunge Leaves

Four new 9,10‐secocycloartane (=9,19‐cyclo‐9,10‐secolanostane) triterpenoidal saponins, named huangqiyenins G–J ( 1 – 4 , resp.), were isolated from Astragalus membranaceus Bunge leaves. The acid hydrolysis of 1 – 4 with 1M aqueous HCl yielded D ‐glucose, which was identified by GC analysis after treatment with L ‐cysteine methyl ester hydrochloride. The structures of 1 – 4 were established by detailed spectroscopic analysis as (3β,6α,10α,16β,24E)‐3,6‐bis(acetyloxy)‐10,16‐dihydroxy‐12‐oxo‐9,19‐cyclo‐9,10‐secolanosta‐9(11),24‐dien‐26‐yl β‐D ‐glucopyranoside ( 1 ), (3β,6a,10α,24E)‐3,6‐bis(acetyloxy)‐10‐hydroxy‐12,16‐dioxo‐9,19‐cyclo‐9,10‐secolanosta‐9(11),24‐dien‐26‐yl β‐D ‐glucopyranoside ( 2 ), (3β,6α,9α,10α,16β,24E)‐3,6‐bis(acetyloxy)‐9,10,16‐trihydroxy‐9,19‐cyclo‐9,10‐secolanosta‐11,24‐dien‐26‐yl β‐D ‐glucopyranoside ( 3 ), and (3β,6α,10α,24E)‐3,6‐bis(acetyloxy)‐10‐hydroxy‐16‐oxo‐9,19‐cyclo‐9,10‐secolanosta‐9(11),24‐dien‐26‐yl β‐D ‐glucopyranoside ( 4 ).     

Precomputed compressive sensing for light transport acquisition

In this article, we propose an efficient and accurate compressive-sensing-based method for estimating the light transport characteristics of real-world scenes. Although compressive sensing allows the efficient estimation of a high-dimensional signal with a sparse or near-to-sparse representation from a small number of samples, the computational cost of the compressive sensing in estimating the light transport characteristics is relatively high. Moreover, these methods require a relatively smaller number of images than other techniques although they still need 500–1000 images to estimate an accurate light transport matrix. Precomputed compressive sensing improves the performance of the compressive sensing by providing an appropriate initial state. This improvement is achieved in two steps: 1) pseudo-single-pixel projection by multiline projection and 2) regularized orthogonal matching pursuit (ROMP) with initial signal. With these two steps, we can estimate the light transport characteristics more accurately, much faster, and with a lesser number of images.     

One-pot synthesis of 1,3,5-tribenzoylbenzenes by three consecutive Michael addition reactions of 1-phenyl-2-propyn-1-ones in pressurized hot water in the absence of added catalysts

Cyclotrimerization of 1‐phenyl‐2‐propyn‐1‐one in pressurized hot water gave 1,3,5‐tribenzoylbenzene in one pot in 65 % yield after 7 min at 200 °C, or in 74 % yield after 60 min at 150 °C. The reaction did not take place in the absence of water, and added base promoted the reaction at 250 °C, suggesting a mechanism of three‐consecutive Michael addition reactions. The reaction rates increased with temperature, but the yield of 1,3,5‐tribenzoylbenzene decreased at the expense of formation of acetophenone as a side product at higher temperatures. p‐Methyl and p‐chloro‐substituents on the phenyl ring retarded and enhanced the reaction, respectively. A mechanism involving the enol of benzoylacetaldehyde at a branching point of the pathway leading to 1,3,5‐tribenzoylbenzene and acetophenone was suggested.     

Ultra‐differentiable classes and intersection theorems

The aim of the paper is to study the relation between ultra‐differentiable classes of functions defined in terms of estimates on derivatives on one hand and in terms of growth properties of Fourier transforms of suitably localized functions in the class on the other hand. We establish this relation for the ultra‐differentiable classes introduced in 6 , 16 , and show that the classes of 6 , 16 , can be regarded as inhomogeneous Gevrey classes in the sense of 22 . We also discuss a number of properties of the weight functions used to define the respective classes and of their Young conjugates.     

Elution control of microparticles with a coupled acoustic-gravity field and orthogonal laminar flow.

Particles accumulated in a coupled acoustic-gravity field, in which the base-material of a particle determines the equilibrium aggregation positions, are eluted from a separation channel by an orthogonal laminar flow. Elution times are controllable by changing the intensity and frequency of the ultrasonic waves.     

Micellar chromatography of inorganic compounds

Micellar chromatography has been used to separate various compounds and to determine the partition coefficients of the compounds between aqueous bulk solution and a micellar pseudophase. The application of this method to inorganic analyses is less common than its application to organic analyses, albeit the former application gives fundamental aspects of the micellar partition of simple ions and promises developments of novel separation. In this review, we focus our attention on the fundamental aspects of micellar chromatography mostly in inorganic analysis of simple ions.     

Development of a target for laser-produced plasma EUV light source using Sn nano-particles

Nano-structured and tin-based targets have been fabricated by the pulsed-laser ablation method, in order to develop efficient and debris-free targets for the laser-produced plasma extreme ultraviolet (EUV) light source at 13.5 nm. Characteristic spectra that have the radiation peak around 13.5 nm were obtained from CO₂ laser produced plasma using the films as a target. A nano-structured target produced EUV light as intense as a bulk target and a narrower line spectrum at 13.5 nm than a bulk target. PACS 32.30.Rj; 52.38.-r; 52.38.Mf; 61.46.+w; 68.37.-d