Monitoring the continuous manufacture of a polymeric foam via a thermokinetic-informed acoustic technique

Polymer foams are difficult to characterise due to rapidly evolving physical features from liquid to porous solid. Swift changes in volume, porosity and moduli render many techniques challenging for the characterisation of the foam curing during a manufacturing process. A technique that employs the longitudinal speed of sound of an ultrasonic signal, informed by a thermokinetic model, is proposed as an in situ, in-line, non-destructive and continuous monitoring tool during the production of rigid polyurethane foams. This study demonstrates that speed of sound measurements are suitable for (a) continuous characterisation of different foaming stages in the polymer reaction and curing; (b) determining the degree of cure for the continuous monitoring of foams, and (c) predicting mechanical properties (i.e., stiffness and Poisson's ratio) of cured foam samples. The validity of this monitoring technique is confirmed by comparison with well-established methods that use physical characteristics (e.g., expansion rate, electrical properties), thermo-kinetic models and mechanical testing. This method positions itself as a monitoring tool and convenient method for determining material stiffness during production.

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How to use saturation monitoring in newborns

Archives of Disease in Childhood - Education and Practice ◽

10.1136/archdischild-2017-313499 ◽

2018 ◽

Vol 104 (1) ◽

pp. 35-42 ◽

Cited By ~ 1

Author(s):

Steven McVea ◽

Michael McGowan ◽

Bharathi Rao

Keyword(s):

Congenital Heart Disease ◽

Intensive Care ◽

Heart Disease ◽

Pulse Oximetry ◽

Congenital Heart ◽

Continuous Monitoring ◽

Screening Tool ◽

Healthcare Providers ◽

Monitoring Tool ◽

First Line

Pulse oximetry is a first-line monitoring tool, used in neonatal medicine routinely as a part of continuous monitoring during intensive care. It is also used to guide response to resuscitation and as a screening tool for congenital heart disease. Despite its widespread use, many healthcare providers are unaware of the underlying principles and limitations of pulse oximetry in neonates. In this article, we will discuss the physiological and technological principles behind the use of saturation monitoring and its use in neonatal practice.

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Daphnia behavioural responses to taste and odour compounds: ecological significance and application as an inline treatment plant monitoring tool

Water Science & Technology ◽

10.2166/wst.2007.158 ◽

2007 ◽

Vol 55 (5) ◽

pp. 23-31 ◽

Cited By ~ 18

Author(s):

S.B. Watson ◽

F. Jüttner ◽

O. Köster

Keyword(s):

Continuous Monitoring ◽

Treatment Plant ◽

Water Treatment Plant ◽

Swimming Velocity ◽

Raw Water ◽

Monitoring Tool ◽

Short Term ◽

Time Period ◽

Volatile Organic ◽

Plant Monitoring

Continuous monitoring of volatile organic compounds (VOC) in raw water is highly desirable for taste and odour management, but in most treatment plants this capacity is lacking. We used a bbe©Daphnia toximeter installed in the Zurich water treatment plant to determine if Daphnia magna could be used to monitor odour compounds in source-water. Trace levels of two widely distributed biogenic VOCs in freshwater: β-cyclocitral and 2(E),4(E),7(Z)-decatrienal were added to the raw water inflow to chambers containing test animals and their behaviour was recorded using a high resolution camera. We observed that each compound elicited a marked short-term increase in Daphnia swimming velocity, but the effect was brief and an acclimation to the compounds was observed after a time period or with repeated additions. The results demonstrate that the toximeter has considerable potential as a tool to monitor certain VOCs in water, and that Daphnia perceive and react to 2(E),4(E),7(Z)-decatrienal and β-cyclocitral at concentrations between 2.5 and 25 μM

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The Quartz Crystal Microbalance as a Continuous Monitoring Tool for the Study of Endothelial Cell Surface Attachment and Growth

Biotechnology Progress ◽

10.1021/bp000003f ◽

2000 ◽

Vol 16 (2) ◽

pp. 268-277 ◽

Cited By ~ 107

Author(s):

T. Zhou ◽

K.A. Marx ◽

M. Warren ◽

H. Schulze ◽

S.J. Braunhut

Keyword(s):

Endothelial Cell ◽

Cell Surface ◽

Quartz Crystal Microbalance ◽

Continuous Monitoring ◽

Quartz Crystal ◽

Monitoring Tool ◽

Surface Attachment ◽

Endothelial Cell Surface

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Adaptation of the animal welfare assessment grid (AWAG) for monitoring animal welfare in zoological collections

Veterinary Record ◽

10.1136/vr.104309 ◽

2017 ◽

Vol 181 (6) ◽

pp. 143-143 ◽

Cited By ~ 11

Author(s):

W. S. M. Justice ◽

M. F. O'Brien ◽

O. Szyszka ◽

J. Shotton ◽

J. E. M. Gilmour ◽

...

Keyword(s):

Animal Welfare ◽

Continuous Monitoring ◽

Practical Method ◽

Monitoring Tool ◽

Welfare Assessment ◽

Legal Requirement ◽

Research Programmes ◽

Computer Based ◽

Animal Welfare Assessment ◽

Taxonomic Groups

Animal welfare monitoring is an essential part of zoo management and a legal requirement in many countries. Historically, a variety of welfare audits have been proposed to assist zoo managers. Unfortunately, there are a number of issues with these assessments, including lack of species information, validated tests and the overall complexity of these audits which make them difficult to implement in practice. The animal welfare assessment grid (AWAG) has previously been proposed as an animal welfare monitoring tool for animals used in research programmes. This computer-based system was successfully adapted for use in a zoo setting with two taxonomic groups: primates and birds. This tool is simple to use and provides continuous monitoring based on cumulative lifetime assessment. It is suggested as an alternative, practical method for welfare monitoring in zoos.

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A photoelectron microscope study of surfaces

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100152021 ◽

1989 ◽

Vol 47 ◽

pp. 10-11

Author(s):

W. Engel ◽

M. Kordesch ◽

A. M. Bradshaw ◽

E. Zeitler

Keyword(s):

Electron Microscopy ◽

High Pressure ◽

Field Strength ◽

Uv Light ◽

Physical Property ◽

Photon Flux ◽

Mercury Lamp ◽

Object Surface ◽

The Sixties ◽

Physical Features

Photoelectron microscopy is as old as electron microscopy itself. Electrons liberated from the object surface by photons are utilized to form an image that is a map of the object's emissivity. This physical property is a function of many parameters, some depending on the physical features of the objects and others on the conditions of the instrument rendering the image.The electron-optical situation is tricky, since the lateral resolution increases with the electric field strength at the object's surface. This, in turn, leads to small distances between the electrodes, restricting the photon flux that should be high for the sake of resolution.The electron-optical development came to fruition in the sixties. Figure 1a shows a typical photoelectron image of a polycrystalline tantalum sample irradiated by the UV light of a high-pressure mercury lamp.

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