Pipe flow of a dense emulsion: Homogeneous shear‐thinning or shear‐induced migration?

The flow field of a 70% concentrated noncolloidal o/w emulsion in a pipe has been investigated by means of Particle Image Velocimetry in a matched refractive index medium. At steady state and in laminar regime, the shape of axial velocity profiles is not parabolic and exhibits a shear‐thinning behavior of the dense emulsion, with a flow index of 0.5 and a negligible yield stress (less than 1 Pa). However, instead of a square root law, the pressure drop increases linearly with U_m. To explain this apparent inconsistency, two mechanisms of different nature are considered. The first originates from a possible relation between the consistency factor and the drop mean diameter. The second mechanism is shear‐induced migration and leads to the development of a concentration gradient in the pipe cross section. Both mechanisms considered reconcile the experimental data, the apparent local shear‐thinning behavior and the linear evolution of the pressure drop with the flow rate. © 2017 American Institute of Chemical Engineers AIChE J, 2017     

Branching versus linear logics yet again

A brief overview is given of the temporal logics used in concurrent program verification and in database and systems specification. The properties of the underlying modal frame structures are analysed. The relative advantages of the linear and branching approaches are discussed. The state versus path formulas controversy is revisited. A meta-linear operatorL is proposed and compared with the in all trajectories operator considered in the language CTL*. The usefulness of the new operator within the context of a layered methodology for database and information systems specification and verification is illustrated. The operator is seen as a frame change operator and other interesting operators of this class are referred. Finitary and infinitary axiomatisations are given for the operatorL. The proof of the completeness of the infinitary axiomatisation is briefly outlined. This proof requires an appropriate extension of the usual Henkin methods.     

The Influence of Organoclay on Polypropylene Composite Films for Synthetic Paper

The influence of type and content of modified montmorillonite (MMT) clay and amount of compatibilizing agent on physical-mechanical properties of polypropylene (PP)/organoclay films were studied. An unexpected decrease in tensile elastic modulus and yield stress was observed, and a striking drop in film density. SEM micrographs showed film microcavitation at polymer/clay interfaces. Experimental design analysis indicated that the most important parameter was the organoclay content: the higher the proportion of MMT, the lower the values of film properties. The addition of compatibilizer promoted an improvement in these film properties, probably due to the formation of less porous film.     

Quantum circuit’s reliability assessment with VHDL-based simulated fault injection

This paper presents a VHDL-based simulated fault injection (SFI) methodology for quantum circuits. The main objective is to attain a high error modeling capability at a technology independent level. For this purpose, gate level simulation models for quantum circuits have been developed using VHDL. The proposed methodology relies on specific techniques inspired from the simulated fault injection techniques developed for classical CMOS circuits: saboteurs and mutants. In order to perform the simulation campaigns, a library of quantum gates and simulated fault injection components has been developed. The simulation results show that a wide range of quantum faults and error models has been addressed. Furthermore, a comparison between the two SFI techniques is presented.     

Estrogen and the neural mediation of female–male mounting in the rat.

Sexually receptive females mount sexually sluggish males to entice them to copulate, and estrogen and male olfactory cues mediate this female–male mounting (FMM) in the rat. This study examined whether brain regions that concentrate steroid hormones and receive olfactory projections were important for the mediation of FMM. Fos induction was observed within the medial amygdala, medial preoptic area, and ventromedial hypothalamus of ovariectomized, hormone-primed rats that displayed FMM compared with rats that did not. Excitotoxic lesions of those regions eliminated FMM, whereas implants of crystalline estradiol benzoate to the ventromedial hypothalamus, but not the medial preoptic area or medial amygdala, restored FMM. These data indicate that the ventromedial hypothalamus is a critical area of convergence of hormonal, olfactory, and somatosensory inputs for FMM. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Designing polylactide/clay nanocomposites for textile applications: Effect of processing conditions,spinning, and characterization

An experimental study was carried out to design polylactide (PLA)-clay nanocomposites for developing fibers. PLA and 1–10 wt % of a selected organomodified bentonite (Bentone® 104-B104) were melt mixed to examine the effect of processing conditions (temperature, shear, residence time) on the morphology of performed polymer nanocomposites (PNC). Because of a good compatibility with PLA matrix, the dispersion of B104 occurred under different conditions without difficulty, and a similar morphology was obtained. The results obtained showed that at low temperature of mixing, the shear stress exerted on polymer has a key role on the extent of intercalation and delamination. Upscale experiments were further performed using optimized conditions and 4 wt % B104 was added to PLA matrix by melt blending to produce PNC for spinning. Then, the recovered PNC were melt spun to produce multifilaments yarns, and it was demonstrated that surprisingly, it is not necessary to use a plasticizer to spin a blend with 4 wt % B104. The properties of the yarns have been studied in terms of clay dispersion as well as thermal, mechanical, and shrinkage properties. B104 could be added up to 4 wt % into PLA without detrimentally sacrificing the tensile strength of melt-spun filaments, especially at high draw ratio. Interestingly, the PNC-based multifilaments were knitted and the flammability studied using cone calorimeter at 35 kW/m². A strong decrease, up to 46%, of the heat release rate was measured. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Photoluminescence of Eu<Superscript>3+</Superscript> ion in SnO<Subscript>2</Subscript> obtained by sol–gel

Photoluminescence data of Eu-doped SnO₂ xerogels are presented, yielding information on the symmetry of Eu³⁺ luminescent centers, which can be related to their location in the matrix: at lattice sites, substituting to Sn⁴⁺, or segregated at particles surface. Influence of doping concentration and/or particle size on the photoluminescence spectra obtained by energy transfer from the matrix to Eu³⁺ sites is investigated. Results show that a better efficiency in the energy transfer processes is obtained for high symmetry Eu³⁺ sites and low doping levels. Emission intensity from ⁵D₀→⁷F₁ transition increases as the temperature is raised from 10 to 240 K, under excitation at 266 nm laser line, because in this transition the multiphonon emission becomes significant only above 240 K. As an extension of this result, we predict high effectiveness for room temperature operation of Eu-based optical communication devices. X-ray diffraction data show that the impurity excess inhibits particle growth, which may influence the asymmetry ratio of luminescence spectra.     

Physicochemical and sensory evaluation of wine brandies aged using oak and chestnut wood simultaneously in wooden barrels and in stainless steel tanks with staves

This study provides innovative information on the simultaneous use of Limousin oak and chestnut wood in the ageing of wine brandy. Ageing was performed in 650‐L wooden barrels and in 3000‐L stainless steel tanks with staves over a 2‐year period. Effect of both kinds of wood in the brandy features depended on the ageing technology. Stainless steel tanks with staves originated lower enrichment of the brandy in dry extract (0.89 vs. 1.25 g L^?1), total phenolics (22.33 vs. 29.40) and low molecular weight extractable compounds (119.83 vs. 231.65 mg L^?1), but promoted a faster evolution of the analytical colour (lower L*, higher C*, a* and b*) and sensory colour (topaz and greenish vs. golden). The aroma and flavour profiles of the brandy were not significantly influenced by the ageing technology. Therefore, it is a promising option for both ageing technologies because it ensures the quality of brandy, together with a lower cost of the wood and exemption of the blending operation.     

A methodology for unveiling global innovation networks: patent citations as clues to cross border knowledge flows

This paper presents a new methodology to describe global innovations networks. Using 167,315 USPTO patents granted in 2009 and the papers they cited, this methodology shows “scientific footprints of technology” that cross national boundaries, and how multinational enterprises interact globally with universities and other firms. The data and the map of these flows provide insights to support a tentative taxonomy of global innovation networks.     

The Influence of Calcite,Fluorite, and Rutile on the Fusion-Related Behavior of Metal Cored Coated Electrodes for Hardfacing

Coated electrodes for SMAW have exhibited their advantages for longer than one century. Means of boosting their performance, particularly for hardfacing, would be a raise in the alloying transfer efficiency and a lowering of the dilution with the substrate, without losing the production capacity. In this study, an evaluation about the operational behavior of a new conception of electrodes for hardfacing is described, i.e., metal cored coated electrodes. Experimental electrodes were produced using metal cored technique to obtain the rods. FeCrMn was used as alloying material at two grain sizes. Using the Mc Lean Anderson experimental design approach, the content ratio of CaCO₃:CaF₂:TiO₂ in the coating was varied. The effect of the coating composition and granulometry of the filling alloying material on the formation a cannon-like end was assessed. Fusion and metal transfer behaviors were evaluated through measurements of fusion and deposition rates, deposition efficiency, and duration and frequencies of short-circuiting. Based on a balance of performances, the most appropriate composition for the coating was determined. It was also observed that a coarser FeCrMn presented better performance.