Computations of Explosive Boiling in Microgravity

Dynamics of the explosive growth of a vapor bubble in microgravity is investigated by direct numerical simulation. A front tracking/finite difference technique is used to solve for the velocity and the temperature field in both phases and to account for inertia, viscosity, and surface deformation. The method is validated by comparison of the numerical results with the available analytical formulations such as the evaporation of a one-dimensional liquid/vapor interface, frequency of oscillations of capillary waves, and other numerical results. Evolution of a three-dimensional vapor nucleus during explosive boiling is followed and a fine scale structure similar to experimental results is observed. Two-dimensional simulations yield a similar qualitative instability growth.     

The place of public space in the lives of Middle Eastern women migrants in Australia

For Middle Eastern migrants to Australia, the process of acculturation is compounded by Islamophobia, which is on the rise, with many incidents occurring in public spaces and targeting women. Through in-depth interviews, this paper examines how women migrants from the Middle East, especially Muslim ones, are affected. The study finds that Middle Eastern women migrants have a different perspective on public space compared to local populations, and this difference stems from their cultural, political and religious backgrounds. These findings can help cities create inclusive and culturally-sensitive public spaces, which catalyze a ‘sense of belonging’ and ‘sense of place’ among migrants.     

Phase/State Transitions of Confectionery Sweeteners: Thermodynamic and Kinetic Aspects

Abstract: It has been said that the key to making high‐quality candy is understanding and controlling the transitions of sugar. Whether found as crystal, glass, or fluid solution, sugars impart the texture necessary to distinguish one confection from another and to provide a unique experience to the consumer. In principle, the phase/state transitions of sugars are best understood through careful application of the phase diagram. However, many, if not all, confections are not at equilibrium, meaning that the phase diagram is simply a starting point for understanding and controlling the state of sugars. An understanding of the thermodynamic driving forces that push a confection towards equilibrium and the kinetic constraints that control the rate of approaching that equilibrium are key elements to creating products with the desired texture, quality, and shelf life. In this review, we summarize the thermodynamic and kinetic aspects of controlling phase/state transitions in sweeteners, with particular emphasis on applications to confectionery products.     

Effect of pre‐treatments based on UV photocatalysis and photo‐oxidation on toluene biofiltration performance

BACKGROUND: The integration of UV photocatalysis and biofiltration seems to be a promising combination of technologies for the removal of hydrophobic and poorly biodegradable air pollutants. The influence of pre‐treatments based on UV_{254 nm} photocatalysis and photo‐oxidation on the biofiltration of toluene as a target compound was evaluated in a controlled long‐term experimental study using different system configurations: a standalone biofilter, a combined UV photocatalytic reactor‐biofilter, and a combined UV photo‐oxidation reactor (without catalyst)‐biofilter. RESULTS: Under the operational conditions used (residence time of 2.7 s and toluene concentrations 600–1200 mg C m^?3), relatively low removal efficiencies (6–3%) were reached in the photocatalytic reactor and no degradation of toluene was found when the photo‐oxidation reactor was operated without catalyst. A noticeable improvement in the performance of the biofilter combined with a photocatalytic reactor was observed, and the elimination capacity of the biological process increased by more than 12 g C h^?1 m^?3 at the inlet loads studied of 50–100 g C h^?1 m^?3. No positive effect on toluene removal was observed for the combination of UV photoreactor and biofilter. CONCLUSIONS: Biofilter pre‐treatment based on UV_{254 nm} photocatalysis showed promising results for the removal of hydrophobic and recalcitrant air pollutants, providing synergistic improvement in the removal of toluene. Copyright © 2011 Society of Chemical Industry     

Component- and Alloy-Specific Modeling for Evaluating Aluminum Recycling Strategies for Vehicles

Previous studies indicated that the availability of mixed shredded aluminum scrap from end-of-life vehicles (ELV) is likely to surpass the capacity of secondary castings to absorb this type of scrap, which could lead to a scrap surplus unless suitable interventions can be identified and implemented. However, there is a lack of studies analyzing potential solutions to this problem, among others, because of a lack of component- and alloy-specific information in the models. In this study, we developed a dynamic model of aluminum in the global vehicle stock (distinguishing 5 car segments, 14 components, and 7 alloy groups). The forecasts made up to the year 2050 for the demand for vehicle components and alloy groups, for the scrap supply from discarded vehicles, and for the effects of different ELV management options. Furthermore, we used a source-sink diagram to identify alloys that could potentially serve as alternative sinks for the growing scrap supply. Dismantling the relevant components could remove up to two-thirds of the aluminum from the ELV stream. However, the use of these components for alloy-specific recycling is currently limited because of the complex composition of components (mixed material design and applied joining techniques), as well as provisions that practically prevent the production of safety-relevant cast parts from scrap. In addition, dismantling is more difficult for components that are currently penetrating rapidly. Therefore, advanced alloy sorting seems to be a crucial step that needs to be developed over the coming years to avoid a future scrap surplus and prevent negative energy use and emission consequences.     

A comparison of two murine monoclonal antibodies humanized by CDR-grafting and variable domain resurfacing

The variable domain resurfacing and CDR-grafting approaches to antibody humanization were compared directly on the two murine monoclonal antibodies N901 (anti-CD56) and anti-B4 (anti-CD19). Resurfacing replaces the set of surface residues of a rodent variable region with a human set of surface residues. The method of CDR-grafting conceptually consists of transferring the CDRs from a rodent antibody onto the Fv framework of a human antibody. Computer-aided molecular modeling was used to design the initial CDR-grafted and resurfaced versions of these two antibodies. The initial versions of resurfaced N901 and resurfaced anti-B4 maintained the full binding affinity of the original murine parent antibodies and further refinements to these versions described herein generated five new resurfaced antibodies that contain fewer murine residues at surface positions, four of which also have the full parental binding affinity. A mutational study of three surface positions within 5 A of the CDRs of resurfaced anti-B4 revealed a remarkable ability of the resurfaced antibodies to maintain binding affinity despite dramatic changes of charges near their antigen recognition surfaces, suggesting that the resurfacing approach can be used with a high degree of confidence to design humanized antibodies that maintain the full parental binding affinity. By comparison CDR-grafted anti-B4 antibodies with parental affinity were produced only after seventeen versions were attempted using two different strategies for selecting the human acceptor frameworks. For both the CDR-grafted anti-B4 and N901 antibodies, full restoration of antigen binding affinity was achieved when the most identical human acceptor frameworks were selected. The CDR-grafted anti-B4 antibodies that maintained high affinity binding for CD19 had more murine residues at surface positions than any of the three versions of the resurfaced anti-B4 antibody. This observation suggests that the resurfacing approach can be used to produce humanized antibodies with reduced antigenic potential relative to their corresponding CDR-grafted versions.     

Properties of Dispersion of Multiwalled Carbon Nanotubes as Cutting Fluid

This article presents the results of experiments performed to evaluate properties of dispersion of multiwalled carbon nanotubes (MWCNT) in water with sodium dodecyl sulfate (SDS) as a dispersant. Different samples of varying concentrations of MWCNTs were prepared for the analysis and properties including thermal conductivity, pH value, viscosity, wettability, etc., were evaluated. These properties were compared with the properties of conventional cutting fluid, which was taken as a mix of water and mineral oil. It was found that the thermal conductivity of the MWCNT dispersion was higher than the conventional cutting fluid by about 42%. There was a decrease in contact angle by about 70%. Thus, dispersing MWCNTs in water with SDS increases the thermal conductivity and wettability of fluid. The pH value of fluid with 0.2 vol% MWCNTs was found to be 8.4. It thus reduced the corrosive nature of water. Nanoparticles of MWCNTs did not have much influence on the viscosity of the base fluid. Thus, the use of MWCNTs in water with SDS appeared to result in a better cutting fluid for machining than conventional cutting fluid.     

A novel approach to the Poisson’s ratio of the yarn

Abstract

The Poisson’s ratio is a fundamental and inherent property of the materials in their reaction to loading. Determining the correct value of the Poisson’s ratio leads to more accurate predictions of the mechanical behavior of the material, especially in employing mechanical or numerical finite element modeling methods. In this study, seven different types of medium and coarse yarn were digitally filmed in seven sections from three various angles while tensile strength testing. Then, longitudinal and transverse strains and consequently, momentary deformation index and Poisson’s ratio of the yarns were calculated. Significance level of the mean Poisson’ ratio was also determined at different angles and sections using statistical comparison test. The results showed that the transverse strain has a convergent state at the end of the test and the start of the yarn breaking occurs at the convergence point. Additionally, in upper sections of yarn near to the movable jaw of the strength tester, the amount of the longitudinal strain increases which leads to reduce in momentary deformation index and Poisson’s ratio of the yarn. Moreover, a sectional mode to measure the Poisson's ratio was presented.     

Design,modeling, and analysis of a high performance piezoelectric energy harvester for intelligent tires

Basic parameters affecting vehicle safety and performance such as pressure, temperature, friction coefficient, and contact‐patch dimensions are measured in intelligent tires via sensors that require electric power for operation and wireless communication to be synchronized to the vehicle monitoring and control system. Piezoelectric energy harvesters (PEHs) can extract a fraction of energy that is wasted as a result of deflection during rolling of tires, and this extracted energy can be used to power up sensors embedded in intelligent tires. A new design of PEH inspired from Cymbal PEHs is introduced, and its performance is evaluated in this paper. Cymbal PEHs are proven to be useful in vibration energy harvesting, and in this paper, for the first time, the modified shape of Cymbal energy harvester is used as strain‐based energy harvester for the tire application. The shape of the harvester is adjusted in a way that it can be safely embedded on the inner surface of tires. In addition to the high performance, ease of manufacturing is another advantage of this new design. A multiphysics model is developed and validated to determine the output voltage, power, and energy of the designed PEH. The modeling results indicated that the maximum output voltage, the maximum electric power, and the accumulated harvested energy are about 3.5 V, 2.8 mW, and 24 mJ/rev, respectively, which are sufficient to power two sensors. In addition, the possibility is shown to supply power to five sensors by increase in piezoelectric material thickness. The effect of rolling tire temperature on the performance of the proposed PEH is also studied.     

Variations in the colorimetric characteristics of verdigris pictorial films depending on the process used to produce the pigment and the type of binding agent used in applying it

The term verdigris embraces a wide range of synthetic pigments whose compositions can also vary. All are salts of copper, but their chemical composition will vary depending on the ingredients used to synthesize them and the conditions in which that synthesis is performed. This article presents the results of applying some of the recipes contained in treatises; the recipes used here, specifically, were taken from the Mappae Clavicula (12th century) and the Ms. of Pierre Lebrun (17th century). The ingredients mentioned present some variations, so that the pigments prepared in turn exhibit significant differences in terms of chemical composition and colorimetric characteristics. The recipes from the Mappae Clavicula, for example, produced monohydrated copper(II) acetate, which upon binding with gum arabic created bluish‐green pictorial films, whereas the colour was yellowish green when the binder was linseed oil. The pigment made from Pierre Lebrun's recipe was a copper(II) chloride mixed with an organo‐copper complex, which can be bound with gum arabic to produce a yellowish‐green colour, whereas mixing with linseed oil presented certain difficulties. These results are derived from colorimetric measurements, which were used to produce values of lightness (L), chroma (C) and hue (H), and also percent reflectance spectra. © 2007 Wiley Periodicals, Inc. Col Res Appl, 32, 414–423, 2007