Bubble Coalescence and Breakup Modeling for Computing Mass Transfer Coefficient

There exist several different numerical models for predicting bubble coalescence and breakup using computational fluid dynamics (CFD). Various combinations of these models will be employed to model a bioreactor process in a stirred reactor tank. A mass transfer coefficient, Kla, has been calculated and compared to those found experimentally by Thermo-Fisher Scientific, to validate the accuracy of currently available mathematical models for population balance equations. These include various combinations of bubble breakup and coalescence models coupled with the calculation of mass transfer coefficients

N<i>e</i>XOS – the design, development and evaluation of a rehabilitation system for the lower limbs

Recent years have seen the development of a number of automated and semi-automated systems to support for physiotherapy and rehabilitation. These deploy a range of technologies from highly complex purpose built systems to approaches based around the use of industrial robots operating either individually or in combination for applications ranging from stroke to mobility enhancement. The NeXOS project set out to investigate an approach to the rehabilitation of the lower limbs in a way which brought together expertise in engineering design and mechatronics with specilists in rehabilitation and physiotherapy. The resulting system has resulted in a prototype of a system which is capable in operating in a number of modes from fully independent to providing direct support to a physiotherapist during manipulation of the limb. Designed around a low cost approach for an implementation ultimately capable of use in a patients home using web-baased strategies for communication with their support team, the prototype NeXOS system has validated the adoption of an integrated approach to its development. The paper considers this design and development process and provides the results from the initial tests with physiotherapists to establish the operational basis for clinical implementation

A eukaryote assemblage intercalated with Marinoan glacial deposits in South Australia

Video of digital X-ray tomographs (µCT) in longitudinal plane through cylinder of siltstone, maximum diameter seen (left to right when viewing movie) is 5.4m

LATE DEVONIAN-TOURNAISIAN CONODONTS FROM THE EASTERN KHYBER REGION, NORTH-WEST PAKISTAN

Conodonts (62 species and subspecies) from acid-leaching of 226 samples from four sections through the Ali Masjid Formation west of Misri Khel in the former South Khyber Agency, north-west Pakistan, are documented by illustrations and distributional data. These indicate that most of this unit, at least in that area, spans the interval Middle crepida Zone (low in the Famennian) to at least Early crenulata Zone (mid-Tournaisian), though a fauna from low in one of the sections produced conodonts indicative of the Late falsiovalis Zone (early Frasnian). Two major hiatuses are inferred: between the Late falsiovalis and Middle crepida zones, and between the Late expansa and Early duplicata zones. Coherence of the conodont biostratigraphy accords with lithologic alignments between the sections. &nbsp

LITHOSTRATIGRAPHY, CONODONT BIOSTRATIGRAPHY AND DEPOSITIONAL ENVIRONMENT OF THE MIDDLE DEVONIAN (GIVETIAN) TO EARLY CARBONIFEROUS (TOURNAISIAN) LIPAK FORMATION IN THE PIN VALLEY OF SPITI (NW INDIA)

Bed-by-bed lithostratigraphic sections combined with sequence stratigraphy and conodont biostratigraphy provide new information on the depositional environment and age of the Lipak Formation in the Pin Valley (Spiti). The formation comprises mixed siliciclastic and calcareous sediments at lower levels, richly fossiliferous limestones with two distinct sandstone incursions at higher levels, and dark mudstones followed by a thin siltstone interval. The upper limit of the Lipak Formation is defined by the angular unconformity below the sandstones of the Permian Gechang Formation. Lithologic correlation with sections in upper Lahaul indicates that, in the Pin Valley, the formation has been truncated just below its characteristic gypsum horizon. The lower boundary of the Lipak Formation is gradational from coastal arenites of the Muth Formation; the mappable boundary is drawn at the first appearance of dark carbonaceous, argillaceous siltstone and shale.Sedimentary structures, microfacies and conodont faunas indicate a general shallow marine depositional environment of the Lipak Formation in the Pin Valley; five sequence stratigraphic units have been distinguished. Conodont data demonstrate that the lowest 33 m of the Lipak Formation of the Pin Valley is mid to late Early varcus Subzone with characteristic species of Icriodus and Bipennatus. A previously unrecognised hiatus at c. 33 m above the base, at the boundary of sequence stratigraphic units S1 and S2, represents the interval Middle varcus Subzone to at least the end of the late Famennian Early expansa Zone. Because this hiatus does not correspond to a mappable boundary, no division of the Lipak Formation into named stratigraphic units is suggested, but we refer informally to the sediments represented by cycle S1 as Lipak A, and the sediments represented by cycles S2-S5 as Lipak B. Determination of S1 as Early varcus Subzone provides a maximum age for the gradationally underlying Muth Formation. At 75 m above the base of the composite Lipak Formation section, a 58 cm black to dark grey shale interval within late Famennian fossiliferous limestones conceivably correlates with the Hangenberg Event (end-Middle praesulcata Zone). Younger conodont faunas of the Lipak Formation -dominated by species of Clydagnathus with species of Bispathodus and Pseudopolygnathus also represented- is shown to extend to the mid-Tournaisian Early crenulata Zone.&nbsp

Mechanical Properties of 8 Mole% Yttria-Stabilised Zirconia for Solid Oxide Fuel Cells

Both high ionic conductivity and mechanical strength are important when considering the potential application of ceramics in solid oxide fuel cells (SOFC). Yttria stabilised zirconia compounds can be used as both the electrolyte and anode support structure in self supporting SOFC and as a result, there is great interest in the development of these materials. The high ionic conductivity of an 8 mol% Y2O3 ZrO2 formulation, must be combined with suitable mechanical hardness and toughness, in order to qualify for SOFC application. The availability of suitable materials has been limited with the majority of suppliers having only small scale manufacturing capability. This study has investigated the physical and mechanical properties of a commercially available ZrO2(Y2O3)0.08 ceramic,. The product was found to contain only the cubic phase and possess the necessary structural characteristics for use in solid oxide fuel cells

The interaction between transpolar arcs and cusp spots

Transpolar arcs and cusp spots are both auroral phenomena which occur when the interplanetary magnetic field is northward. Transpolar arcs are associated with magnetic reconnection in the magnetotail, which closes magnetic flux and results in a "wedge" of closed flux which remains trapped, embedded in the magnetotail lobe. The cusp spot is an indicator of lobe reconnection at the high-latitude magnetopause; in its simplest case, lobe reconnection redistributes open flux without resulting in any net change in the open flux content of the magnetosphere. We present observations of the two phenomena interacting--i.e., a transpolar arc intersecting a cusp spot during part of its lifetime. The significance of this observation is that lobe reconnection can have the effect of opening closed magnetotail flux. We argue that such events should not be rare

Effect of Celluclast 1.5L on the Physicochemical Characterization of Gold Kiwifruit Pectin

The effects of Celluclast 1.5L concentration on the physicochemical characterization of gold kiwifruit pectin was evaluated. Varying the enzyme concentration affected the pectin yield and pectin physicochemical properties. The viscosity of extracted pectin was largely dependent on the enzyme concentration. Celluclast 1.5L with medium concentration exhibited the highest viscosity. Varying the enzyme concentration also influenced the molecular weight distribution. High molecular weight (Mw) pectin (1.65 × 106 g/mol) was obtained when the medium concentration was used. Overall, the study clearly reflects the importance of taking into consideration the amount of cellulytic enzyme added in order to determine the final quality of pectin

Collaborating to support the use and development of open educational resources: a White Rose Libraries research project

Interest in open educational resources (OER) has grown recently due to many external factors, including the restrictive, unsustainable and expensive business models for teaching materials that are being used by some publishers. In February 2021, the libraries of the UK White Rose University Consortium (White Rose Libraries) initiated a research project to explore the potential of OER and to create guidance in the form of an OER toolkit that could be used across all three institutions, and more widely. The project also aimed to seek improvements in the discovery of OER in the Ex Libris Primo discovery service which is used by all three libraries. This article outlines the methodology used to ascertain the needs of the libraries’ user groups to inform the development of the toolkit. A survey of academic staff across all three institutions was conducted, followed by user experience interviews. The survey findings established that more than half of respondents knew little or nothing about OER, and over half also said that they would be likely or extremely likely to consider using or adapting OER, clearly demonstrating the need for more awareness raising and guidance. The survey interview findings were then used to develop and refine the toolkit