scholarly journals V. Similarity of motion in relation to the surface friction of fluids

1914 ◽  
Vol 214 (509-522) ◽  
pp. 199-224 ◽  
Keyword(s):  
General Relation ◽  
Surface Friction ◽  
The Body ◽  
Thin Plates ◽  
Flat Plates ◽  
Series Of Experiments ◽  
The Subject ◽  
Different Dimensions ◽  
Laws Of Motion ◽  
A Current

The laws of the surface friction of fluids have formed the subject of many important investigations during the last 100 years, among which may be mentioned the work of Poiseuille, Darcy and Osborne Reynolds on the friction of water flowing in pipes, that of William Froude on the resistance of thin plates towed in water, and the corresponding experiments of Zahm on flat plates in a current of air. Researches in this field have also been carried out by Brix, Stockalper, Mallock, Coker, Gebers, Brightmore, Grindley and Gibson, and others. As a result, the effect on the resistance, of the dimensions of the body over whose surface the fluid moves, and of the velocity of flow, are tolerably well known for the particular fluid and character of motion observed. In the case of the surface friction of water in pipes, the researches of Osborne Reynolds have demonstrated the existence of similar motions in pipes of different dimensions, hut, as far as the authors are aware, no systematic series of experiments appears to have been made for the purpose of establishing a general relation which would be applicable to all fluids and conditions of flow, although the existence of such relationships for different aspects of the problem were predicted as a consequence of the laws of motion by Stokes in 1850, by Helmholtz in 1873, by Osborne Reynolds in 1882, by Lord Rayleigh in 1899 and 1909, and as has been pointed out by Sir George Greenhill, were foreshadowed by Newton in Proposition 32, Book II., of the ‘Principia.’

scholarly journals Surface friction: Experiments with steam and water in pipes

1916 ◽  
Vol 92 (640) ◽  
pp. 337-353 ◽  
Keyword(s):  
General Relation ◽  
Surface Friction ◽  
Solid Surfaces ◽  
Experimental Investigations ◽  
Mathematical Formula ◽  
The Past ◽  
The Subject ◽  
Laws Of Motion ◽  
Parallel Case

During the past hundred years much work, both theoretical and experimental, has been carried out with a view to determining tbs character of the laws governing tbs resistance to tangential motion between solid surfaces and liquids or gases. A general relation between the dimensions of the surface, the velocity, the density of the fluid, and its viscosity bad been surmised as a consequence of the laws of motion by Stokes, Helmholtz, and Osborne Reynolds, but it was left to Lord Rayleigh to show, from the principle of dynamical similarity, that the phenomena involved could be expressed definitely by a simple mathematical formula. The laws governing tbs friction between solid surfaces and water have formed the subject of experimental investigations by Froude, Osborne Reynolds, Darcy, etc., whilst the parallel case of the resistance to motion between solid surfaces and perfect gases has occupied the attention of Zahm, Brix, Stockalper, and others. Practically all these investigators devoted their energies to experimental determinations of the friction in the medium which they employed, and it was not until the subject was taken up by Stanton and Pannell that any attempt was made to investigate the similarity, under certain conditions, of the motion of fluids which differed widely amongst themselves in their properties of densities and viscosities. The same investigators also took up the question of the limits of accuracy of the formulæ currently accepted at the time and used in calculations of surface friction.

scholarly journals VI. On a new photometer, with its application to determine the relative intensities of artificial light, &c

1825 ◽  
Vol 115 ◽  
pp. 141-146 ◽  
Keyword(s):  
The Body ◽  
Thin Plates ◽  
Artificial Light ◽  
Repulsive Energy ◽  
Heated Body ◽  
The Subject

1. In a paper which I lately communicated to the Edin­burgh Philosophical Journal, I endeavoured to show, that caloric flies off from the surface of a heated body by the re­pulsive energy existing between its own molecules, and con­sequently, that their velocity increases with the temperature of the body. This conclusion I deduced from the fact, dis­covered by Delaroche, that invisible caloric freely permeates very thin plates of glass, in the same manner as light, but that it is completely intercepted by thicker plates. If the tem­perature of the body be raised, the atoms of caloric will be brought nearer each other, their repulsive energy augmented, their velocity increased, and consequently, they will now find their way through a plate of glass which formerly intercepted them. If the temperature of the body be raised still higher, the molecules of caloric will acquire a velocity sufficient to permeate the various humours of the eye, and produce an impression on the retina, or in other words, they will become light. From this view of the subject, I was naturally led to the invention of an instrument which would be affected by visible caloric or light, whilst it would not be sensibly acted upon by invisible coloric, or heat. In short, I was led to the invention of a photometer, which appears to be the most accurate and delicate which has yet been described. But though such were the theoretical views which led to the invention of the instrument, its perfection does not depend upon any peculiar theory of light and heat. It is founded on the axiom, that equal volumes of air are equally expanded by equal quantities of light, converted into heat by absorption by black surfaces: and also on the well established principle that the quantity of light diminishes as the square of the distance of the luminous source from the object on which it is received.

scholarly journals On the origin and destiny of cholesterol in the animal organism. Part XII.—On the excretion of sterols in man

1921 ◽  
Vol 92 (648) ◽  
pp. 358-367 ◽  
Keyword(s):  
Body Weight ◽  
Uric Acid ◽  
Special Reference ◽  
Cholesterol Content ◽  
The Body ◽  
Rapid Loss ◽  
Animal Organism ◽  
University College ◽  
Series Of Experiments ◽  
The Subject

In Part X of this series [vol. 86, p. 13 (1912)]—“On the Excretion of Cholesterol by Man”—Ellis and Gardner, from analyses of the dried fæces collected during a series of experiments, carried out by R. H. A. Plimmer, M. Dick, and E. C. Lieb, at the Institute of Physiology, University College, and published under the title of “A Metabolism Experiment, with Special Reference to Uric Acid,” came to the conclusion that in man the excretion of cholesterol in the fæces can be largely accounted for by that taken in with the food, provided that the body weight remains constant; if, however, a rapid loss in weight takes place, as in illness, the output of sterol exceeds the intake. Further work has shown that this conclusion requires modification. In the above-mentioned investigation only one subject was experimented on and the cholesterol-content of the diet was not obtained by analysis of samples of the food actually consumed by the subject under experiment, since the examination of the fæces in question was not undertaken until long after the completion of Plimmer, Dick, and Lieb’s investigation, and was of the nature of an afterthought.

I. On the relation of radiant heat to aqueous vapour

1863 ◽  
Vol 153 ◽  
pp. 1-12
Keyword(s):  
Rock Salt ◽  
Royal Society ◽  
Physical Property ◽  
Radiant Heat ◽  
The Body ◽  
Thin Plates ◽  
Polished Surface ◽  
Cause Of Error ◽  
Series Of Experiments ◽  
Possible Cause

I haye already placed before the Royal Society an account of some experiments which brought to light the remarkable fact that the body of our atmosphere, that is to say the mixture of oxygen and nitrogen of which it is composed, is a comparative vacuum to the calorific rays, its main absorbent constituent being the aqueous vapour which it contains. It is very important that the minds of meteorologists should be set at rest on this subject—that they should be able to apply, without misgiving, this newly revealed physical property of aqueous vapour; for it is certain to have numerous and important applications. I therefore thought it right to commence my investigations this year with a fresh series of experiments upon atmospheric vapour, and I now have the honour to lay the results of these experiments before the Royal Society. Rock-salt is a hygroscopic substance. If we breathe on a polished surface of rock-salt, the affinity of the substance for the moisture of the breath causes the latter to spread over it in a film which exhibits brilliantly the colours of thin plates. The zones of colour shrink and finally disappear as the moisture evaporates. Visitors to the International Exhibition may have witnessed how moist were the pieces of rock-salt exhibited in the Austrian and Hungarian Courts. This property of the substance has been referred to by Professor Magnus as a possible cause of error in my researches on aqueous vapour; a film of brine deposited on the surface of the salt would produce the effect which I had ascribed to the aqueous vapour. I will, in the first place, describe a method of experiment by which even an inexperienced operator may avoid all inconvenience of this kind.

scholarly journals The origin and destiny of cholesterol in the animal organism. Part X. —On the excretion of cholesterol by man, when fed on various diets

1912 ◽  
Vol 86 (584) ◽  
pp. 13-18 ◽  
Keyword(s):  
Bile Salts ◽  
Blood Stream ◽  
Egg White ◽  
The Body ◽  
Animal Economy ◽  
University College London ◽  
Series Of Experiments ◽  
The Subject ◽  
Normal Food ◽  
Herring Roe

In earlier papers of this series we have shown that cholesterol is never excreted in the normal fæces of herbivorous animals such as horses, cattle, sheep, and rabbits. In the case of carnivora such as dogs and cats, provided the body weight remains constant, the cholesterol excreted in the fæces can be all accounted for by that naturally ingested with the food. Klein in his experiments also arrived at a similar conclusion. Evidence was also brought forward which rendered probable the view that, in herbivora, at any rate, cholesterol is a substance which is strictly conserved in the animal economy, that when the destruction of the red blood corpuscles and possibly other cells takes place in the liver, their cholesterol is excreted in the bile, and that the cholesterol of the bile is re-absorbed in the intestine along with the bile salts, finding its way into the blood stream to be used in cell anabolism ; further, that any waste of cholesterol might be made up from that taken in with the food. This latter process would be limited in herbivorous animals by the fact that their normal food does not contain cholesterol, but isomeric substances such as phytosterol, which have to be converted into cholesterol before utilisation, and in carnivorous animals by the partial, or even complete, change of cholesterol into coprosterol which takes place under certain dietetic conditions. In man, under normal conditions, cholesterol is never excreted as such in the fæces, but always in the form of coprosterol. It seemed therefore desirable to estimate the amounts of coprosterol found in the fæces of man under various dietetic conditions. The opportunity of making such investigations was very kindly afforded us by Dr. R. H. A. Plimmer, who handed over to us the dried fæces collected during a series of experiments carried out in the Physiological Institute, University College, London, and published in the ‘Journal of Physiology,’ August 26, 1909, under the title of “ A Metabolism Experiment, with Special Reference to the Origin of Uric Acid,” by R. H. Aders Plimmer, Maxwell Dick, and Charles C. Lieb. The subject of the experiment was a healthy man, aged 39. The three diets selected were chosen so that each yielded 110 grm. protein, 240 grm. carbohydrate, and 100 grm. fat per diem. The carbohydrate and fat constituents consisted of potato and butter, and the protein constituents of (1) beefsteak, (2) egg-white, or (3) herring-roe.

Description of a percussion shell, to be fired horizontally from a common gun

1833 ◽  
Vol 2 ◽  
pp. 296-298
Keyword(s):  
Spiral Motion ◽  
Resisting Medium ◽  
Cylindrical Form ◽  
Air Blowing ◽  
Series Of Experiments ◽  
The Subject ◽  
Inclined Planes ◽  
Rotatory Motion ◽  
A Current ◽  
Made In

In this paper, the author first considers the theory of rifles, with which the subject of it is intimately connected; and regarding it as an admitted principle, that irregularities in the flight of shot arise from irregularities either in their surface or substance, shows how the rotatory motion of a rifle ball, by presenting every part uniformly to the action of the resisting medium, obviates the effect of these irregularities. The spiral or rotatory motion of the ball in rifles, is generally supposed to arise wholly from the re-action of the grooves in the barrel, or from the indentations made by them in the surface of the ball; but the author, taking into consideration the powerful action of the air on projectiles, is led to conclude that the rotation of a grooved ball may be sustained during its flight, or even produced originally by the resistance of the air acting on the inclined planes formed by the grooves, on the same principle as the rotation of the sails of a windmill. These considerations led the author to conceive the possibility of giving the spiral motion to grooved shot fired from a plain barrel; an idea which, he remarks, seems to have also occurred to Mr. Robins, who left, however, no clue to enable us to discover the nature of his plan. He accordingly commenced a series of experiments for the purpose, and, abandoning all idea of success with spherical shot, adopted the cylindrical form. His first trials were made in the summer of 1821. Hemispherical ends were adapted to cylindrical shot, but abandoned, it being found desirable so to dispose the weight as to give the greatest possible length to the shot; grooves of various dimensions were tried, and were found not to answer when narrow, but required to be wide enough to allow their sides to be exposed, from one end to the other, to a current of air blowing straight between them. In 1822, some further experiments were made at Woolwich, with grooved leaden shot fired from musket barrels, and with wooden shot from a 5^-inch howitzer, in which the shot, being received on targets, or in banks of earth, were in numerous instances found to have flown in the manner expected, i. e. point foremost. Similar trials with grooved leaden bullets from a plain barrel, were made in 1823, to the extent of several hundreds; and the balls, when well made, were always found to fly end foremost. Large wooden grooved shot were also fired from a 24-pounder, at Kinsale Fort, and on some occasions by night with lighted fusees in their sides, by which contrivance it was distinctly seen that the spiral motion was acquired and maintained steadily throughout their flight.

Diaghilev and British Writing

2009 ◽  
Vol 27 (1) ◽  
pp. 65-92
Author(s):  
Susan Jones
Keyword(s):  
Visual Arts ◽  
The Body ◽  
The Novel ◽  
Literary Responses ◽  
Literary Aesthetics ◽  
Ballets Russes ◽  
The Arts ◽  
The Subject ◽  
And Gender ◽  
Opening Up

This article explores the diversity of British literary responses to Diaghilev's project, emphasising the way in which the subject matter and methodologies of Diaghilev's modernism were sometimes unexpectedly echoed in expressions of contemporary British writing. These discussions emerge both in writing about Diaghilev's work, and, more discretely, when references to the Russian Ballet find their way into the creative writing of the period, serving to anchor the texts in a particular cultural milieu or to suggest contemporary aesthetic problems in the domain of literary aesthetics developing in the period. Figures from disparate fields, including literature, music and the visual arts, brought to their criticism of the Ballets Russes their individual perspectives on its aesthetics, helping to consolidate the sense of its importance in contributing to the inter-disciplinary flavour of modernism across the arts. In the field of literature, not only did British writers evaluate the Ballets Russes in terms of their own poetics, their relationship to experimentation in the novel and in drama, they developed an increasing sense of the company's place in dance history, its choreographic innovations offering material for wider discussions, opening up the potential for literary modernism's interest in impersonality and in the ‘unsayable’, discussions of the body, primitivism and gender.

Compulsive Bodies, Creative Bodies: Beckett'sQuadand Agency in the 21stCentury

2018 ◽  
Vol 27 (1) ◽  
pp. 5-21
Author(s):  
Amanda Dennis
Keyword(s):  
Human Action ◽  
The Body ◽  
New Materialism ◽  
Illustrative Case ◽  
Repetitive Movement ◽  
Repetitive Tasks ◽  
The Subject ◽  
Object Oriented Ontology ◽  
Geological Space ◽  
Alternative Reading

Lying in ditches, tromping through mud, wedged in urns, trash bins, buried in earth, bodies in Beckett appear anything but capable of acting meaningfully on their environments. Bodies in Beckett seem, rather, synonymous with abjection, brokenness, and passivity—as if the human were overcome by its materiality: odours, pain, foot sores, decreased mobility. To the extent that Beckett's personae act, they act vaguely (wandering) or engage in quasi-obsessive, repetitive tasks: maniacal rocking, rotating sucking stones and biscuits, uttering words evacuated of sense, ceaseless pacing. Perhaps the most vivid dramatization of bodies compelled to meaningless, repetitive movement is Quad (1981), Beckett's ‘ballet’ for television, in which four bodies in hooded robes repeat their series ad infinitum. By 1981, has all possibility for intentional action in Beckett been foreclosed? Are we doomed, as Hamm puts it, to an eternal repetition of the same? (‘Moments for nothing, now as always, time was never and time is over, reckoning closed and story ended.’)This article proposes an alternative reading of bodily abjection, passivity and compulsivity in Beckett, a reading that implies a version of agency more capacious than voluntarism. Focusing on Quad as an illustrative case, I show how, if we shift our focus from the body's diminished possibilities for movement to the imbrication of Beckett's personae in environments (a mound of earth), things, and objects, a different story emerges: rather than dramatizing the impossibility of action, Beckett's work may sketch plans for a more ecological, post-human version of agency, a more collaborative mode of ‘acting’ that eases the divide between the human, the world of inanimate objects, and the earth.Movements such as new materialism and object-oriented ontology challenge hierarchies among subjects, objects and environments, questioning the rigid distinction between animate and inanimate, and the notion of the Anthropocene emphasizes the influence of human activity on social and geological space. A major theoretical challenge that arises from such discourses (including 20th-century challenges to the idea of an autonomous, willing, subject) is to arrive at an account of agency robust enough to survive if not the ‘death of the subject’ then its imbrication in the material and social environment it acts upon. Beckett's treatment of the human body suggests a version of agency that draws strength from a body's interaction with its environment, such that meaning is formed in the nexus between body and world. Using the example of Quad, I show how representations of the body in Beckett disturb the opposition between compulsivity (when a body is driven to move or speak in the absence of intention) and creative invention. In Quad, serial repetition works to create an interface between body and world that is receptive to meanings outside the control of a human will. Paradoxically, compulsive repetition in Beckett, despite its uncomfortable closeness to addiction, harnesses a loss of individual control that proposes a more versatile and ecologically mindful understanding of human action.

Predicting the citation and impact factor of terms for scientific publications using machine learning algorithms

2020 ◽  
Author(s):  
Aleksey Klokov ◽  
Evgenii Slobodyuk ◽  
Michael Charnine
Keyword(s):  
Machine Learning ◽  
Semantic Processing ◽  
The Body ◽  
Machine Learning Algorithms ◽  
Scientific Publications ◽  
Text Data ◽  
Semantic Relationships ◽  
Subject Areas ◽  
The Subject ◽  
Scientific Environment

The object of the research when writing the work was the body of text data collected together with the scientific advisor and the algorithms for processing the natural language of analysis. The stream of hypotheses has been tested against computer science scientific publications through a series of simulation experiments described in this dissertation. The subject of the research is algorithms and the results of the algorithms, aimed at predicting promising topics and terms that appear in the course of time in the scientific environment. The result of this work is a set of machine learning models, with the help of which experiments were carried out to identify promising terms and semantic relationships in the text corpus. The resulting models can be used for semantic processing and analysis of other subject areas.

Research of the activity and viability of spermatozoa at different concentrations and proportions of diluents after incubation

2020 ◽  
pp. 88-95
Author(s):  
Svitlana Lobchenko ◽  
Tetiana Husar ◽  
Viktor Lobchenko
Keyword(s):  
Plasma Concentration ◽  
Incubation Time ◽  
Coefficient Of Variation ◽  
Incubation Medium ◽  
Wide Range ◽  
Series Of Experiments ◽  
The Subject ◽  
Boar Spermatozoa ◽  
Native Plasma ◽  
Better Than

The results of studies of the viability of spermatozoa with different incubation time at different concentrations and using different diluents are highlighted in the article. (Un) concentrated spermatozoa were diluented: 1) with their native plasma; 2) medium 199; 3) a mixture of equal volumes of plasma and medium 199. The experiment was designed to generate experimental samples with spermatozoa concentrations prepared according to the method, namely: 0.2; 0.1; 0.05; 0.025 billion / ml. The sperm was evaluated after 2, 4, 6 and 8 hours. The perspective of such a study is significant and makes it possible to research various aspects of the subject in a wide range. In this regard, a series of experiments were conducted in this area. The data obtained are statistically processed and allow us to highlight the results that relate to each stage of the study. In particular, in this article it was found out some regularities between the viability of sperm, the type of diluent and the rate of rarefaction, as evidenced by the data presented in the tables. As a result of sperm incubation, the viability of spermatozoa remains at least the highest trend when sperm are diluted to a concentration of 0.1 billion / ml, regardless of the type of diluent used. To maintain the viability of sperm using this concentration of medium 199 is not better than its native plasma, and its mixture with an equal volume of plasma through any length of time incubation of such sperm. Most often it is at this concentration of sperm that their viability is characterized by the lowest coefficient of variation, regardless of the type of diluent used, which may indicate the greatest stability of the result under these conditions. The viability of spermatozoa with a concentration of 0.1 billion / ml is statistically significantly reduced only after 6 or even 8 hours of incubation. If the sperm are incubated for only 2 hours, regardless of the type of diluent used, the sperm concentrations tested do not affect the viability of the sperm. Key words: boar, spermatozoa, sperm plasma, concentration, incubation, medium 199, activity, viability, rarefaction.

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