Hydraulic linkage of a storm water tank to a karst spring (Gallusquelle)

Grundwasser - A significant proportion of the global water supply is ensured by karst aquifers. However, these are often highly vulnerable to contamination. A storm water tank...     

Apparatus for the vertical orientation cone calorimeter testing of flexible polyurethane foams

Of concern to regulators and fire safety engineers is how flexible polyurethane foam drips and flows during burning. Specifically, flexible polyurethane foam forms a burning ‘pool’ of liquid as the foam decomposes, which can lead to accelerated flashover events. To fully study this phenomenon where the ‘pool fire’ accelerates heat release, large‐scale tests like the furniture calorimeter (American Society of Testing and Materials (ASTM) E1537) are used, and no small‐scale technique exists. In this paper, we present our work in developing a new sample holder that works with a bench‐scale heat release test, the cone calorimeter (ASTM E1354). The holder was built upon designs developed by the National Institute of Standards and Technology, which placed the foam in a cage in a vertical orientation during cone calorimeter testing. In this paper, we show the schematics for this test apparatus, as well as results obtained with this apparatus on four different flexible foams (shape memory and high‐density foam, flame retarded and non‐flame retarded). We compare the results from the vertical testing with that obtained via traditional horizontal ASTM E1354 testing. The advantages and disadvantages of this new apparatus are discussed in this paper. Copyright © 2014 John Wiley & Sons, Ltd.     

Introduction to the special issue on IEEE NEWCAS 2017

A contactless detector is presented for evaluating hand tremors caused by exercise-induced fatigue and early Parkinson’s disease. The device consists of a spiral coil, a microcontroller, and an inductive sensor circuitry. Theory shows that the resonant frequency of the circuitry increases when the distance between the hand and the spiral coil decreases, thus small variations of distance from tremor can be detected from the changes of resonant frequencies. A mechanical hand was built for experiments to simulate human hand tremors with repeatability at a fixed frequency. The magnitudes and frequencies of the tremors in the mechanical hand were quantitatively identified using the inductive sensor. Hence, feasibility and accuracy of the contactless hand tremor detector were determined. A triaxial accelerometer was used for comparison. By comparing spectral distributions and magnitudes of the tremors, the inductive sensor performed better than the accelerometer. The detector was applied to evaluate actual hand tremors of three subjects who had undergone exercise to induce tremors. The tremor waveform amplitudes of the subjects were quantitatively analyzed by the standard deviations method. The increased signal energies of exercise-induced tremor within 8–12 Hz were confirmed. Then, a subject with early Parkinson’s disease was evaluated by the proposed hand tremor detector. The tremor magnitudes and frequencies of the patient hand were quantitatively identified within in 4–7 Hz. Therefore, the new contactless hand tremor detector can be developed as a clinical instrument for monitoring the fatigue symptoms of post-exercise and diagnosing the early Parkinson’s disease.     

The influence of macromolecular architecture on the critical aggregation concentration of large amphiphilic starch derivatives

A range of hyperbranched emulsifiers were prepared by reaction between starch and 2-octen-1-yl succinic anhydride (OSA, commonly used in the food industry), under slightly basic conditions in water, leading to starches bearing hydrophobic OSA groups randomly distributed along the chains. By using different starch backbones and varying the amount of OSA during the synthesis, amphiphilic OSA-modified starches were obtained that formed aggregates in water and having controlled structural parameters. These parameters were characterized using ¹H NMR, multiple-angle laser light scattering and size-exclusion chromatography. The critical aggregation concentration (CAC) was measured for samples with different levels of OSA modification, of macromolecular size and degree of starch branching. Increasing the dispersity in macromolecular size and/or degree of OSA substitution noticeably decreased the CAC. The results are interpreted in terms of the branching structure and conformation of the modified starches: all findings can be understood in terms of the various influences of molecular size, composition and flexibility. The structural factors affecting the CAC of large hyperbranched surfactants are found to be similar to those seen with smaller and simpler branched synthetic surfactants.     

Primary Li-air cell development

In the present communication, we report on recent researches for optimizing the performance of a primary organic-based Li-air cell. These researches focus on new processing technologies for a high capacity and high rate capable carbon cathode, and the development of oxygen selective membranes based on polysiloxane and methacrylate-polysiloxane copolymers. These membranes, generally classified as silicone rubbers exhibit high permeability for oxygen and impede water transport from the atmosphere into the Li-air cell and solvent loss from the cell into the atmosphere.     

Copper accumulation in soils from two different‐aged apricot orchards in Central Otago,New Zealand

In recent years there has been a move in New Zealand to convert small, uneconomic orchards to other agricultural uses. Overseas research has demonstrated that copper from fungicide sprays often accumulates in the soils of orchards and can cause certain problems for plant growth and livestock. To date, no assessments appear to have been made of the degree of copper accumulation in such older orchards in New Zealand. This study presents the results of an assessment of two well‐established apricot orchards in the Central Otago region of South Island, New Zealand.

Two aspects of the results are surprising. The first is the relatively low levels of copper in the soil when compared with results from another orchard in the region. That orchard is 18 years old and mean soil copper has already reached 100.0 μg/g, indicating a much faster rate of accumulation than in the two orchards in the current study. The second unexpected result is that the younger orchard has a significantly higher level of copper than the older orchard. Reasons for these findings are discussed in relation to apparent differences in soil properties.     

Tow impregnation during resin transfer molding of bi-directional nonwoven fabrics

A model has been developed for analyzing resin impregnation of fiber tows during resin transfer molding of bi-directional nonwoven fiber performs. The model is based on the existence of two main regions of resin flow: the macropore space formed among fiber tows and the micropore space formed among individual fiber filaments within a tow. The large difference in permeability between these two regions of flow leads to the potential for void formation during resin transfer molding. The model was formulated for both constant flow rate and constant pressure mold filling. For ambient pressure mold filling, the model predicts a difference in the size of the voids and distribution between axial tows (oriented along the flow direction) and transverse tows (oriented in the transverse direction). When vacuum is imposed on the mold, the model predicts the same resin impregnation behavior for both axial and transverse tows. Furthermore, given sufficient time, voids generated under vacuum mold filling will eventually collapse because of the absence of an opposing internal void pressure. In addition to insights on void formation, the model also provides a basis for the study of the relationship between resin transfer molding parameters and the resin impregnation process.