A Rough and Ready Galvanic Battery

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Problems of perceptibility affecting formal design in Nontonal music

The thesis argues that the absence of traditional referential elements,-such as tonality and metre, affects the exactitude with which the listener perceives certain aspects of nontonal music. It claims that the listener might impose his own interpretation on a work in which the musical patterns are too complex to be perceived exactly and that, in extreme cases, the patterns which the listener reads into the music may be completely subjective. The thesis examines the extent to which Webern and some post-Webernian composers determine the listener's response to their music and shows that certain aspects of Webern's music are simple enough to be easily grasped and to be perceived exactly and that these aspects control the way in which the listener understands Webern's music. It suggests that the nature of the musical material and the procedures employed in much post-Webernian music precludes the use of many of the controls found in Webern, but that other methods of determining the listener's response to the music can be found in some of the works of the post-Webernian composers. It argues, however, that in some post-Webernian music, and particularly in that composed using chance or serial methods, the listener's response to the music may not be determined by the composer. The thesis claims' that many of the important formal problems facing post-Webernian music must be considered in relation to the problems of auditory perception

Transformer Oil Passivation and Impact of Corrosive Sulphur

In recent years a significant volume of research has been undertaken in order to understand the recent failures in oil insulated power apparatus due to deposition of copper sulphide on the conductors and in the insulation paper. Dibenzyl Disulfide (DBDS) has been found to be the leading corrosive sulphur compound in the insulation oil [1]. The process of copper sulphide formation and the deposition in the paper is still being investigated, but a recently proposed method seems to be gaining some confidence [1]. This method suggests a two-step process; initially the DBDS and some oil soluble copper complexes are formed. Secondly the copper complexes are absorbed in the paper insulation, where they then decompose into copper sulphide [2]. The most commonly used mitigating technique for corrosive sulphur contaminated oil is passivation, normally using Irgamet 39 or 1, 2, 3-benzotriazole (BTA). The passivator is diluted into the oil to a concentration of around 100ppm, where it then reacts with the copper conductors to form a complex layer around the copper, preventing it from interacting with DBDS compounds and forming copper sulphide. This research project will investigate the electrical properties of HV transformers which have tested positive for corrosive sulphur, and the evolution of those properties as the asset degrades due to sulphur corrosion. Parallel to this the long term properties of transformers with passivated insulation oil will be analysed in order to understand the passivator stability and whether it is necessary to keep adding the passivator to sustain its performance. Condition monitoring techniques under investigation will include dielectric spectroscopy, frequency response analysis, recovery voltage method (aka interfacial polarisation) amongst others. Partial discharge techniques will not be investigated, as the voltage between the coil plates is low and therefore it will not contribute significantly to the overall insulation breakdown, in corrosive oil related faults [3]. The goal of this research is to establish key electrical properties in both passivated and non-passivated power transformers that demonstrate detectable changes as the equipment degrades due to the insulation oil being corrosive

Black dyes for coir fibre: 3 practical considerations

Earlier trials on Synacril Black A, Benzamin Black DS 167% and Suprexcel Black VY- three possible substitute dyes for Chlorazol Black E -showed the effect of variations in dyebath conditions on the amount of dye deposited on coir (Canning, A. J., Jarman, C. G. and Mykoluk, S. M. (1979) Black dyes for coir fibre. Part 2. Evaluation of selected dyes. Report of the Tropical Products Institute, L52). Further trials, in which both different concentrations of dye in the bath, and a standing bath were used, have now been carried out to obtain additional data on the exhaustion characteristics of the three dyes. Additionally, the effect of variations in dyebath conditions on the quality of colour, and the amount of each of the three dyes that needs to be deposited on to the fibre to produce an acceptable black, have been assessed. With all three dyes, dyebath exhaustion was approached more slowly with increased dyebath concentration. As a consequence, when additional dye is used, dyeing time must be increased to obtain the most efficient use of dye. Since the proportion of dye that exhausts from the bath is also reduced, particularly with the higher dyebath concentrations or the shorter dyeing times, increasingly large additions of dye are required in order to intensify the visual depth of shade. With low dyebath concentrations of the two direct dyes (Benzamin Black and Suprexcel Black), allowing the liquor to cool during dyeing could reduce heating costs since the exhaustion obtained after 1.5 hours at 95°C followed by cooling was similar to that obtained after 6 hours at 95°C. However, with deeper shades the opportunity for reducing heating costs by reducing dyeing time at 95°C and then cooling is less. The inclusion of sodium carbonate in the dyebath could also result in savings on dyestuff. When using a standing bath technique with Benzamin Black, significantly different exhaustion/time relationships were obtained with each batch of fibre. As a consequence there would be considerable practical difficulties in using this dye with this technique. On the other hand, the exhaustion of Suprexcel Black was only slightly affected by the use of replenished liquors and a standing bath technique could reduce costs. Because of its almost complete exhaustion, there would be no advantage in using a standing bath with the basic dye Synacril Black. All the dyes gave better light-fastness properties when they were concentrated at the periphery of the fibre rather than when they penetrated more deeply: however, staining of adjacent fabrics was greater. The distribution of the dye within the fibre did not affect the visual colour. All three dyes should produce black colours which are technically similar to those of commercial samples of black coir. The amounts which need to be deposited on the fibre to produce an acceptable black are estimated as approximately: Benzamin Black DS 167% - 19g per kilogram of fibre; Suprexcel Black VY - 22g per kilogram of fibre; Synacril Black A - 10g per kilogram of fibre. Fastness properties of the blacks vary with the dye and the technique used to apply it. Information on the development of optimum dyeing conditions is appended

Pad-batch dyeing of plant fibres

This guide describes a new method of dyeing plant fibres which are to be made into hats and handbags and other craft work. The pages on this side of the book are intended as a guide for the instructor and extension worker to help him introduce the method to craft workers. We hope the booklet will also be of use to the craft dyers and workers themselves so we have designed the left-hand pages specially for them. The left-hand pages describe the method in photographs with short, clear instructions. The right-hand pages give more information and will help extension workers and instructors to understand and explain the method

An assessment of the strength of knots and splices used as eye terminations in a sailing environment

Research into knots, splices and other methods of forming an eye termination has been limited, despite the fact that they are essential and strongly affect the performance of a rope. The aim of this study was to carry out a comprehensive initial assessment of the breaking strength of eye terminations commonly used in a sailing environment, thereby providing direction for further work in the field. Supports for use in a regular tensile testing machine were specially developed to allow individual testing of each sample and a realistic spread of statistical data to be obtained. Over 180 break tests were carried out on four knots (the bowline, double bowline, figure-of-eight loop and perfection loop) and two splices (three-strand eye splice and braid-on-braid splice). The factors affecting their strength were investigated. A statistical approach to the analysis of the results was adopted. The type of knot was found to have a significant effect on the strength. This same effect was seen in both types of rope construction (three-strand and braid-on-braid). Conclusions were also drawn as to the effect of splice length, eye size, manufacturer and rope diameter on the breaking strength of splices. Areas of development and further investigation were identified

Service use preceding and following first referral for psychiatric emergency care at a short-stay crisis unit: A cohort study across three cities and one rural area in England

Background: Internationally, hospital-based short-stay crisis units have been introduced to provide a safe space for stabilisation and further assessment for those in psychiatric crisis. The units typically aim to reduce inpatient admissions and psychiatric presentations to emergency departments. Aims: To assess changes to service use following a service user’s first visit to a unit, characterise the population accessing these units and examine equality of access to the units. Methods: A prospective cohort study design (ISCTRN registered; 53431343) compared service use for the 9 months preceding and following a first visit to a short-stay crisis unit at three cities and one rural area in England. Included individuals first visited a unit in the 6 months between 01/September/2020 and 28/February/2021. Results: The prospective cohort included 1189 individuals aged 36 years on average, significantly younger (by 5–13 years) than the population of local service users (<.001). Seventy percent were White British and most were without a psychiatric diagnosis (55%–82% across sites). The emergency department provided the largest single source of referrals to the unit (42%), followed by the Crisis and Home Treatment Team (20%). The use of most mental health services, including all types of admission and community mental health services was increased post discharge. Social-distancing measures due to the COVID-19 pandemic were in place for slightly over 50% of the follow-up period. Comparison to a pre-COVID cohort of 934 individuals suggested that the pandemic had no effect on the majority of service use variables. Conclusions: Short-stay crisis units are typically accessed by a young population, including those who previously were unknown to mental health services, who proceed to access a broader range of mental health services following discharge

Deterministic optical polarisation in nitride quantum dots at thermoelectrically cooled temperatures.

We report the successful realisation of intrinsic optical polarisation control by growth, in solid-state quantum dots in the thermoelectrically cooled temperature regime (≥200 K), using a non-polar InGaN system. With statistically significant experimental data from cryogenic to high temperatures, we show that the average polarisation degree of such a system remains constant at around 0.90, below 100 K, and decreases very slowly at higher temperatures until reaching 0.77 at 200 K, with an unchanged polarisation axis determined by the material crystallography. A combination of Fermi-Dirac statistics and k·p theory with consideration of quantum dot anisotropy allows us to elucidate the origin of the robust, almost temperature-insensitive polarisation properties of this system from a fundamental perspective, producing results in very good agreement with the experimental findings. This work demonstrates that optical polarisation control can be achieved in solid-state quantum dots at thermoelectrically cooled temperatures, thereby opening the possibility of polarisation-based quantum dot applications in on-chip conditions