The study of the lipophilicity of some aminoalkanol derivatives with anticonvulsant activity

A series of new (phenoxyethyl)aminoalkanol derivatives were synthesized and evaluated for their anticonvulsant activity. The most promising compound seemed to be (R,S)‐1N‐[(2,6‐dimethyl)phenoxyethyl]amino‐2‐butanol, which displayed anti‐MES activity (in mice, i.p.) with protective index (TD₅₀/ED₅₀) of 5.712, corresponding to that of phenytoin (6.6), carbamazepine (4.9) and valproate (1.7). The lipophilicity of compounds 1–17 exhibiting anticonvulsant activity was investigated. Their lipophilicities (R_M0) were determined using reversed‐phase thin‐layer chromatography (RP‐TLC) with a mixture of acetone and water as mobile phases. The partition coefficients of 1–17 (logP) were also calculated using two computer programs (Pallas and ALOGPS) and compared with R_M0. The relationship between anticonvulsant activity and lipophilicity of the tested substances was estimated. Copyright © 2010 John Wiley & Sons, Ltd.     

Crystallographic report: Diiodo[tris(2‐pyridyl)amine]zinc(II), [(C5H4N)3N]ZnI2

The zinc(II) atom in the molecule of [(C₅H₄N)₃N]ZnI₂ is tetrahedrally coordinated to two nitrogen atoms of the tris(2‐pyridyl)amine ligand and two iodides. The coordination moieties are connected to give a linear structure by intermolecular π–π interactions between the pyridyl rings. Copyright © 2003 John Wiley & Sons, Ltd.     

Short communication: An alternative and effective catalyst for the silastannation of arylacetylenes with Me3SiSnBu3 at room temperature

The palladium‐catalyzed silastannation of acetylenes with tributyl(trimethylsilyl)stannane in the presence of triethylphosphite is reported for the first time. The reaction occurs at room temperature to give (Z)‐silyl(stannyl)ethenes in high yields. The protodemetallation of the resulting adducts with HCl–tetraethylammonium chloride is described first, which demonstrates that the reaction is governed only by the stability of a carbonium ion arising from the protonation to (Z)‐silyl(stannyl)ethenes rather than the hard and soft acid and base principle, i.e. the β‐cation stabilization effect (σ–π stabilization one) of a stannyl group in the carbonium ion is rather significant. Copyright © 2004 John Wiley & Sons, Ltd.     

Bit-rate Flexible Picosecond Pulse Width Conversion with All-optical Mono-stable Multivibrator Laser Diode

An optical mono-stable multivibrator laser diode (MM-LD) is realized by using a multi-electrode distributed feedback laser diode. All-optical pulse-width conversion of ultra-short pulses to non-return-to-zero (NRZ) is achieved using an MM-LD. The MM-LD is adopted for a wide range of bit-rates between 2-10 Gbit/s by tuning the DC bias. Data format transformation from 10-Gbit/s return-to-zero optical signals to NRZ optical-signals is achieved with error free operation. Converted optical signals, which have a narrower spectral bandwidth and lower peak power than when input, are transmitted using a 1.3-μm zero dispersion fiber (1.3Aλ₀-SMF).     

RAS: An efficient probe to characterize Si(0 0 1)-(2 × 1) surfaces

A complete inspection of the capabilities of reflectance anisotropy spectroscopy (RAS) in studying the adsorption of molecules or atoms on the Si(0 0 1)-(2 × 1) surface is presented. First, a direct comparison between RA spectra recorded on the clean Si(0 0 1)-(2 × 1) and the corresponding topography of the surface obtained using scanning tunneling microscopy (STM) allows us to quantify the mixing of the two domains that are present on the surface. Characteristic RA spectra recorded for oxygen, hydrogen, water, ethylene, benzene are compared to try to elucidate the origin of the optical structures. Quantitative and qualitative information can be obtained with RAS on the kinetics of adsorption, by monitoring the RA signal at a given energy versus the dose of adsorbate; two examples are presented: H₂/Si(0 0 1) and C₆H₆/Si(0 0 1). Very different behaviours in the adsorption processes are observed, making of this technique a versatile tool for further investigations of kinetics.     

Poisson半群的边界值

在空间Ｌｐ（Ｒｎ），１≤ｐ＜∞中，Ｐｏｉｓｏｎ算子半群ｅ－－△ｚ是右半平面Ｒｅｚ＞０上的解析半群．本文考虑它的边界值，证明了闭稠定算子－ｉ－△对某个α≥０生成了一个指数有界（Ｉ＋－△）－α 半群．     

On trees with a maximum proper partial 0-1 coloring containing a maximum matching

I prove that in a tree in which the distance between any two endpoints is even, there is a maximum proper partial 0-1 coloring such that the edges colored by 0 form a maximum matching.     

The physical meaning of scattering matrix singularities in coupled-channel formalisms⋆

The physical meaning of bare and dressed scattering matrix singularities has been investigated. Special attention has been attributed to the role of the well-known invariance of the scattering matrix with respect to the field transformation of the effective Lagrangian. Examples of evaluating bare and dressed quantities in various models are given.