Plasmon energy chemical phase mapping of reactive multilayers

An analytical method of quantitative phase identification and mapping on the nanoscale is presented based on correlative similarity mapping from spectrum images within electron energy loss spectroscopy across the low‐loss plasmon region. The method is applied to map the reaction layer formation for heat treated Cu–Al–Al₂O₃ thin films. Coexistence of residual Al pockets next to polycrystalline but epitaxial CuAl₂ as main reaction product is found as well as a distinctive interfacial plasmon region. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Interfacial characterisation and mechanical properties of heat treated non-woven kenaf fibre and its reinforced composites

This paper reports on the comprehensive characterisation of heat treated kenaf fibre (KF) and its composites. The kenaf fibres were modified by heating for 2.5–12.5 h inside a drying oven. Heat treatment produces an increase in the crystallinity index and fibre strength of KF. The highest value of KF strength was recorded by applying heat treatment of 10 h on KF. The heat treatment results in the partial removal of impurities/extractives on the KF surface which is detected by scanning electron microscopy and X-ray photoelectron spectroscopy. Atomic force microscopy results signify the decrease of roughness, the increase in peak area density and the increase of the adhesion force on the surface area of heat treated KF. The effect of the heat treatment in enhancing the interface bonding characteristics between the KF and unsaturated polyester matrix can be reflected by the interlaminar shear strength (ILSS) and dynamic mechanical analysis value of the composites. The flexural properties of the composites showed a similar trend to ILSS. However, the fracture toughness revealed contrasting results. Water absorption induced a drastic loss of the mechanical properties of the composites albeit better retention of properties was observed in the case of heat-treated KF composites.     

Theoretical study of the effect of liquid desiccant mass flow rate on the performance of a cross flow parallel-plate liquid desiccant-air dehumidifier

A computer simulation using MATLAB is investigated to predict the distribution of air stream parameters (humidity ratio and temperature) as well as desiccant parameters (temperature and concentration) inside the parallel plate absorber. The present absorber consists of fourteen parallel plates with a surface area per unit volume ratio of 80 m²/m³. Calcium chloride as a liquid desiccant flows through the top of the plates to the bottom while the air flows through the gap between the plates making it a cross flow configuration. The model results show the effect of desiccant mass flow rate on the performance of the dehumidifier (moisture removal and dehumidifier effectiveness). Performance comparisons between present cross-flow dehumidifier and another experimental cross-flow dehumidifier in the literature are carried out. The simulation is expected to help in optimizing of a cross flow dehumidifier.     

Effect of radiation on conductivity of solid PVA–KOH–PC composite polymer electrolytes

The aim of this work is to enhance the room temperature conductivity of solid alkaline composite polymer electrolytes (ACPEs) based on polyvinyl alcohol/potassium hydroxide/propylene carbonate (PVA–KOH–PC) composites by cross-linking the PVA and bond scission of the PC by γ-radiation. The ACPEs were prepared by solvent-casting technique and irradiated with doses up to 200 kGy at room temperature. The microstructure of the ACPEs was measured using XRD spectrometer, and the results show the structural change from semicrystalline to amorphous, indicating that the cross-linking has been achieved at higher doses. It was found that the PKOH composite at 40 wt% KOH and PPC composite at 60 wt% PC show higher conductivities. The conductivity of the PKPC composites is dominated by dc conductivity at higher frequencies and that PC with 60 wt% has the highest conductivity at a dose of 200 kGy.Paper presented at the International Conference on Functional Materials and Devices 2005, Kuala Lumpur, Malaysia, June 6–8, 2005.     

Cause of hydration/dehydration in condensed organic materials: synthesis of hydrophobic pores

[reaction: see text] The unique solid-state hydration/dehydration properties of the diacid (+/-)-1e in comparison with other homologues of the same family are studied. Hydrophobic enhancement, which is a consequence of the loss of water molecules from (+/-)-1e chains, is a property that can be exploited to achieve organic condensed systems for nonpolar molecules by interstitial van der Waals confinement.     

Carijenone, a novel class of bicyclic prostanoid from the eastern Pacific octocoral Carijoa multiflora

[structure: see text] An unprecedented biogenetically interesting bicyclic prostanoid 1, carijenone, has been isolated from the eastern Pacific octocoral Carijoa multiflora. The C-12 oxygenated function, characteristic of the coral cyclopentanone fatty acid derivatives, is involved in the formation of a five-membered oxane ring fused to the cyclopentane network. Its structure and stereochemistry were determined on the basis of spectral studies and molecular mechanics calculations.     

Deposition of overlays by electrostatic self-assembly in long-period fiber gratings

It was proved that the deposition of an overlay material onto a long-period fiber grating causes important shifts in the wavelengths of the typical attenuation bands that are caused by coupling between cladding and core modes [Opt. Lett. 27, 682 (2002)]. A theoretical model for analyzing a multilayer cylindrical waveguide is presented that permits the phenomenon to be understood and predicted. An overlay of higher refractive index than the cladding starts to guide a mode if a certain thickness value is exceeded. This causes large shifts in the resonance wavelength induced by the grating. One important application of this phenomenon to sensors is enhancement of the sensitivity of a long-period fiber grating to ambient conditions. Theoretical results are corroborated with experimental ones obtained by electrostatic self-assembly.     

About И-quantifiers

Gabbay and Pitts observed that the Fraenkel–Mostowski model of set-theory supports useful notions of name-abstraction and fresh-name. In order to understand their work in a more general setting we introduce the notions of -units and -relations in a regular category D. A -relation is given by a functor A # (_-):DD and we show that in the case that D is a topos then A # (_-) has a right adjoint [A](_-) that can be thought of as an object of abstractions. We also explore the existence of a right adjoint to [A](_-) and relate it to the name swapping operations considered as fundamental by Gabbay and Pitts. We present many examples of categories where this notions occur and we relate the results here with Pitts' Nominal Logic.