Voltammetric Behaviour of LMO at the Nanoscale: A Map of Reversibility and Diffusional Limitations

Understanding and optimizing single particle rate behaviour is normally challenging in composite commercial lithium-ion electrode materials. In this regard, recent experimental research has addressed the electrochemical Li-ion intercalation in individual nanosized particles. Here, we present a thorough theoretical analysis of the Li⁺ intercalation voltammetric behaviour in single nano/micro-scale LiMn₂O₄ (LMO) particles, incorporating realistic interactions between inserted ions. A transparent 2-dimensional zone diagram representation of kinetic-diffusional behaviour is provided that allows rapid diagnosis of the reversibility and diffusion length of the system depending on the particle geometry. We provide an Excel file where the boundary lines of the zone diagram can be rapidly recalculated by setting input values of the rate constant, and diffusion coefficient, . The model framework elucidates the heterogeneous behaviour of nanosized particles with similar sizes but different shapes. Hence, we present here an outlook for realistic multiscale modelling of real materials.     

Relativity and impossibility of superluminal motion

I prove that not only particle motion but also wave propagation cannot be faster than light according to relativity.     

Electrochemical genosensing of Salmonella, Listeria and Escherichia coli on silica magnetic particles

A magneto-genosensing approach for the detection of the three most common pathogenic bacteria in food safety, such as Salmonella, Listeria and Escherichia coli is presented. The methodology is based on the detection of the tagged amplified DNA obtained by single-tagging PCR with a set of specific primers for each pathogen, followed by electrochemical magneto-genosensing on silica magnetic particles. A set of primers were selected for the amplification of the invA (278 bp), prfA (217 bp) and eaeA (151 bp) being one of the primers for each set tagged with fluorescein, biotin and digoxigenin coding for Salmonella enterica, Listeria monocytogenes and E. coli, respectively. The single-tagged amplicons were then immobilized on silica MPs based on the nucleic acid-binding properties of silica particles in the presence of the chaotropic agent as guanidinium thiocyanate. The assessment of the silica MPs as a platform for electrochemical magneto-genosensing is described, including the main parameters to selectively attach longer dsDNA fragments instead of shorter ssDNA primers based on their negative charge density of the sugar-phosphate backbone. This approach resulted to be a promising detection tool with sensing features of rapidity and sensitivity very suitable to be implemented on DNA biosensors and microfluidic platforms.     

Amorphous Polymers’ Foaming and Blends with Organic Foaming-Aid Structured Additives in Supercritical CO2, a Way to Fabricate Porous Polymers from Macro to Nano Porosities in Batch or Continuous Processes

Organic polymers can be made porous via continuous or discontinuous expansion processes in scCO₂. The resulting foams properties are controlled by the interplay of three groups of parameters: (i) Chemical, (ii) physico-chemical, and (iii) technological/process that are explained in this paper. The advantages and drawbacks of continuous (extrusion, injection foaming) or discontinuous (batch foaming) foaming processes in scCO₂, will be discussed in this article; especially for micro or nano cellular polymers. Indeed, a challenge is to reduce both specific mass (e.g., ρ < 100 kg·m⁻³) and cell size (e.g., average pore diameter ϕ_average^pores < 100 nm). Then a particular system where small “objects” (coreshells CS, block copolymer MAM) are perfectly dispersed at a micrometric to nanometric scale in poly(methyl methacrylate) (PMMA) will be presented. Such “additives”, considered as foaming aids, are aimed at “regulating” the foaming and lowering the pore size and/or density of PMMA based foams. Differences between these additives will be shown. Finally, in a PMMA/20 wt% MAM blend, via a quasi one-step batch foaming, a “porous to nonporous” transition is observed in thick samples. A lower limit of pore size (around 50 nm) seems to arise.     

Polymer Nanodiscs and Their Bioanalytical Potential

Membrane proteins (MPs) play a pivotal role in cellular function and are therefore predominant pharmaceutical targets. Although detailed understanding of MP structure and mechanistic activity is invaluable for rational drug design, challenges are associated with the purification and study of MPs. This review delves into the historical developments that became the prelude to currently available membrane mimetic technologies before shining a spotlight on polymer nanodiscs. These are soluble nanosized particles capable of encompassing MPs embedded in a phospholipid ring. The expanding range of reported amphipathic polymer nanodisc materials is presented and discussed in terms of their tolerance to different solution conditions and their nanodisc properties. Finally, the analytical scope of polymer nanodiscs is considered in both the demonstration of basic nanodisc parameters as well as in the elucidation of structures, lipid–protein interactions, and the functional mechanisms of reconstituted membrane proteins. The final emphasis is given to the unique benefits and applications demonstrated for native nanodiscs accessed through a detergent free process.     

Anwendung von Radionukliden in der Elektrotechnik

The effect of etching conditions on the energy resolution was studied. In the present work cellulose nitrate CN-85 films were used as Solid State Nuclear Track Detectors. There exists a relation between the etching condition and the energy resolution.     

Characterization of Oil Fly Ash Particles by Electron Probe Microanalysis

Abstract

An automated electron microprobe was used to characterize more than 25000 fly ash particles with diameters between 1μm and 200μm, which were collected in two fractions from the stack of an oil fired power plant under two different burning conditions. Sample preparation procedures were developed to insure a quantitative particle transfer from the collection container to a Nuclepore filter and the automated localization of the carbonaceous particles in the backscattered electron image was optimized. Size distributions were measured and the results were interpreted in terms of the burning conditions of the power plant.     

Resonance Light Scattering Method to Determine Binding Ratio and Functional Affinity Constant of Antigen/Antibody Immunoreaction

Abstract

Based on the immunoreaction equation and the quality function law, a method of determining the binding ratio and the affinity constant of antibody/antigen immunoreaction has been developed by measuring resonance light scattering (RLS) signals of the polystyrene latex particles. According to the method, the binding ratio and affinity constant of HIgG binding with goat anti-HIgG equal 0.71 and 47.3 mL/mg; that is, 1 mol HIgG can be bound with 1.4 mol goat anti-HigG. This new method is much simpler and easier to carry out when studying immunoreaction kinetics and determining the binding ratio and affinity constant.     

Bubble collapse in compressible fluids using a spectral element marker particle method. Part 1. Newtonian fluids

This paper is concerned with the development of a high‐order numerical scheme for the modelling of two‐phase Newtonian flows. The companion paper, herein referred to as Part 2, extends the scheme to two‐phase viscoelastic flows. The particular problem of the collapse of a two‐dimensional bubble in the vicinity of a rigid boundary is considered. The governing equations are discretized using the spectral element method, and the two phases are modelled using a marker particle method. The marker particle scheme is validated using the Zalesak slotted disk rotation test problem. A comprehensive set of results is presented for the problem of bubble collapse near a rigid wall, and qualitative agreement is obtained with other numerical studies and experimental observations. Viscous effects are shown to inhibit bubble collapse and prevent jet formation and are therefore likely to have a mitigating effect on cavitation damage.Copyright © 2011 John Wiley & Sons, Ltd.     

Synthesis and Applications of Compartmentalised Molecular Polymer Brushes

Polymer science is rapidly advancing towards the precise construction of synthetic macromolecules of formidable complexity. Beyond the impressive advances in control over polymer composition and uniformity enabled by the living polymerisation revolution, the introduction of compartmentalisation within polymer architectures can elevate their functionality beyond that of their constituent parts, thus offering immense potential for the production of tailor‐made nanomaterials. In this Minireview, we discuss synthetic routes to complex molecular brushes with discrete chemical compartments and highlight their potential in the development of advanced materials with applications in nanofabrication, optics and functional materials.