Reticulated Porous Foam Ceramics with Different Surface Chemistries

The aim of this study was to discuss the influence of different filter surface chemistries on the properties of foam filters. For reliable results, it is essential to ensure comparable structural properties (cell size and strut thickness) for all different surface chemistries (Al₂O₃, MgAl₂O₄, 3Al₂O₃·2SiO₂, SiO₂, and TiO₂) possess the same structural properties (cell size and strut thickness). Filters made of 100% of the investigated materials and alumina skeletons coated with the investigated materials were prepared. The coated alumina samples were sintered in one and two steps. The processing route with two sintering steps resulted in improved mechanical properties and comparable shrinkage and strut thickness. The 100% bulk foams possessed different pore sizes due to the differences of the material shrinkage. In this study, a comparison of the experimental investigated properties of the ceramic foam filters and the theoretically calculated values for foam materials derived from the bulk material properties is established.     

Optical Measurement Accuracy in the Case of Non-classical Light

Abstract

The influence of optical elements on the statistical properties of the input radiation is analysed by quantum-theoretical means for a representative optical arrangement consisting of beam splitters as well as for various types of grating spectrometers. In particular non-classical light states are studied. Optimum conditions for the maintenance of the signal-to-noise ratio of sub-Poissonian input radiation are derived.     

Latent motion spaces for full-body motion editing

We explore an approach to full-body motion editing with linear motion models, prioritized constraint-based optimization and latent-space interpolation. By exploiting the mathematical connections between linear motion models and prioritized inverse kinematics (PIK), we formulate and solve the motion editing problem as an optimization function whose differential structure is rich enough to efficiently optimize user-specified constraints within the latent motion space. Performing motion editing within latent motion spaces has the advantage of handling pose transitions and consequently motion flow by construction from single key-frame editing. To handle motion adjustments from multiple key-frame and trajectory constraints, we developed a latent-space interpolation technique by exploiting spline functions. Such an approach handles per-frame adjustments generating smooth animations, while avoiding the computational expense of joint space interpolations. We demonstrate the usefulness of this approach by editing and generating full-body reaching and walking jump animations in challenging environment scenarios.     

Mechanical material characterization of photosensitive polymers

In addition to the development of materials and technologies for smart HARMST applications the analysis of the thermo-mechanical material properties seems to be necessary to describe the photosensitive polymers applied. To do this, a microtensile analysis system has been developed to determine stress–strain curves, Young’s modulus and Poisson’s ratio. The results are compared with those of dynamical mechanical thermal analysis and discussed.     

‘Why Can’t the Future be More Like the Past?’ Planning History Track,Association of European Schools of Planning (AESOP), Annual Congress,Department of Civic Design,University of Liverpool, 15–18 July 2009

AESOP’s 2009 Congress was hosted by the University of Liverpool as part of the centenary celebration of its Department of Civic Design, the world’s oldest university planning school. ‘Why Can’t the Future be More Like the Past?’ was the conference title on all the banners and conference bags – an oddly querulous question, nevertheless it did the trick in getting participants to think historically throughout AESOP 2009. Michael Hebbert and Dirk Schubert ran a planning history track for six of the conference’s seven parallel session slots. Their call for papers elicited 30 abstracts which reduced to 17 papers, a comfortable quantity allowing good time for presentation and discussion. The track had the fortune to be allocated a wood‐panelled Architecture lecture theatre with superb projection facilities – more than one speaker gasped at the glory of their own PowerPoint images.     

The role of conductive pathways in the conductivity and rheological behavior of poly(methyl methacrylate)–graphite composites

Up to now, research on the dynamic process of conductive network formation has tended to focus on composite particles with one‐dimensional geometry, such as carbon black and carbon nanotubes. However, studies on this subject based on fillers with two‐dimensional structure, such as graphite, are rare in the literature. In this work, the dynamic percolation and rheological properties of poly(methyl methacrylate) (PMMA)–graphite composites under an electric field were investigated. The activation energies of conductive network formation and polymer matrix mobility were calculated from the temperature dependence of the percolation time and the zero‐shear viscosity. It was found that the activation energy calculated from the zero‐shear viscosity was not influenced by the electric field in the concentration range investigated, but the electric field had an effect on the activation energy calculated from the percolation time. This finding emphasizes that the electrical and rheological properties have different physical origins. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43810.     

Temperature Dependence of Efficiency in GaInN/GaN Light‐Emitting Diodes with a GaInN Underlayer

The temperature dependence of the efficiency (i.e., temperature‐mediated efficiency droop) in blue light‐emitting diodes (LEDs) is investigated. A GaInN/GaN LED with a GaInN underlayer having an indium mole fraction of 8% shows less temperature dependence of efficiency, compared to the LED without an underlayer. Better carrier confinement in the active region of the LED with a GaInN underlayer is proposed to reduce carrier leakage from the active region at high temperature. The results indicate that the insertion of an underlayer leads to an improvement of the LED's radiative efficiency and its high‐temperature‐tolerant performance.     

Regime transition in viscous and pseudo viscous systems: A comparative study

A comprehensive quantitative study on the effect of liquid viscosity (1 ≤ µ_L ≤ 1149 mPa‐s) on the local flow phenomena of the gas phase in a small diameter bubble column is performed using ultrafast electron beam X‐ray tomography. The internal dynamic flow structure and the bubble size distribution shows a dual role of the liquid viscosity on the hydrodynamics. Further, the effect of solid concentration (C_s = 0.05, 0.20) on the local flow behavior of the gas phase is studied for the pseudo slurry viscosities similar to the liquid viscosities of the gas–liquid systems. The effects of liquid and pseudo slurry viscosities on flow structure, bubble size distribution, and gas phase distribution are compared. The bubble coalescence is significantly enhanced with the addition of particles as compared to the system without particles for apparently same viscosity. The superficial gas velocity at which transition from homogeneous bubbly to slug flow regime occurs is initiated by the addition of particles as compared to the particle free system for apparently same viscosity. © 2014 American Institute of Chemical Engineers AIChE J, 60: 3079–3090, 2014