scholarly journals III. Investigations of the specific heat of solid bodies

1865 ◽  
Vol 155 ◽  
pp. 71-202 ◽  
Keyword(s):  
Specific Heat ◽  
Thermal Action ◽  
General View ◽  
Specific Heats ◽  
General Law ◽  
Different Temperatures ◽  
The Times ◽  
The Individual ◽  
Solid Bodies

I. About the year 1780 it was distinctly proved that the same weights of different bodies require unequal quantities of heat to raise them through the same temperature, or on cooling through the same number of thermometric degrees, give out unequal quantities of heat. It was recognized that for different bodies the unequal quantities of heat, by which the same weights of different bodies are heated through the same range, must be determined as special constants, and considered as characteristic of the individual bodies. This newly discovered property of bodies Wilke designated as their specific heat , while Crawford described it as the comparative heat, or as the capacity of bodies for heat . I will not enter upon the earliest investigations of Black, Irvine, Crawford, and Wilke, with reference to which it may merely be mentioned that they depend essentially on the thermal action produced when bodies of different temperatures are mixed, and that Irvine appears to have been the first to state definitely and correctly in what manner this thermal action (that is, the temperature resulting from the mixture) depends on the original temperature, the weights, and the specific heats of the bodies used for the mixture. Lavoisier and Laplace soon introduced the use of the ice-calorimeter as a method for determining the specific heat of bodies; and J. T. Mayer showed subsequently that this determination can be based on the observation of the times in which different bodies placed under comparable conditions cool to the same extent by radiation. The knowledge of the specific heats of solid and liquid bodies gained during the last century, and in the first sixteen years of the present one, by these various methods, may be left unmentioned. The individual determinations then made were not so accurate that they could be compared with the present ones, nor was any general conclusion drawn in reference to the specific heats of the various bodies. 2. Dulong and Petit’s investigations, the publication of which commenced in 1818, brought into the field more accurate determinations, and a general law. The investigations of the relations between the specific heats of the elements and their atomic weights date from this time, and were afterwards followed by similar investigations into the relations of the specific heats of compound bodies to their composition. In order to give a general view of the results of these investigations, it is desirable to present, for the elements mentioned in the sequel, a synopsis of the atomic weights assumed at different times, and of certain numbers which stand in the closest connexion with these atomic weights.

scholarly journals The thermal capacity of pure iron

1940 ◽  
Vol 174 (956) ◽  
pp. 1-15 ◽  
Keyword(s):  
Heat Capacity ◽  
Specific Heat ◽  
Thermal Capacity ◽  
Total Heat ◽  
Large Temperature ◽  
Specific Heats ◽  
The Past ◽  
Heat Curve ◽  
Different Temperatures ◽  
The Subject

Although the heat capacity of iron at different temperatures has been the subject of a number of investigations in the past, it is only recently that iron of purity greater than 99.9 % has been available. Furthermore, in most previous determinations the property actually measured has been the total heat over a relatively large temperature range. Specific heats deduced from such measurements are liable to appreciable error, since if the total heat curve is smoothed, small fluctuations in the specific heat will be concealed, whereas if the actual observations are retained without smoothing, fluctuations which have no physical existence may appear in the result. Thus, suppose that the total heat is measured from 50 to 145 and from 50 to 155° C, the former being in error by 1 part in 1000 in excess and the latter the same amount in defect, the error in the specific heat over the range 145-155° C will be almost 2%. Evidently a real variation of 1 or 2% would be liable to pass unnoticed if any smoothing is undertaken, and conversely, fluctuations of this order may be introduced spuriously if the observations are used without smoothing. In general, calorimetry from high temperatures cannot be carried out to an accuracy of 1 part in 1000, and in any case, even this accuracy is insufficient at temperatures of the order of 1000° C.

Temperature-dependent Specific Heats of Dry Soil Materials

1975 ◽  
Vol 12 (2) ◽  
pp. 209-212 ◽  
Author(s):  
B. D. Kay ◽  
J. B. Goit
Keyword(s):  
Specific Heat ◽  
Functional Relation ◽  
Absolute Temperature ◽  
Temperature Dependent ◽  
Specific Heats ◽  
Proportionality Constant ◽  
Single Temperature ◽  
Different Temperatures ◽  
Dry Soil ◽  
The Absolute

Specific heat measurements have been made on several soil materials at different temperatures in order to obtain a generalized functional relation between specific heat and temperature. Specific heats were found to vary linearly with temperature from 200 to 300 °K (−73 °C to + 27 °C) and extrapolated close to zero at 0 °K. Consequently, the functional relation between specific heat and temperature for soil materials may be approximated as Cp = mT where Cp is the specific heat, T is the absolute temperature (°K), and m is a proportionality constant. Such a relation permits the prediction of the specific heats at any temperature normally encountered in the field once reliable specific heats have been determined at a single temperature.

ON THE SPECIFIC HEATS OF TUNGSTEN, MOLYBDENUM, AND COPPER

1933 ◽  
Vol 8 (3) ◽  
pp. 282-303 ◽  
Author(s):  
H. L. Bronson ◽  
H. M. Chisholm ◽  
S. M. Dockerty
Keyword(s):  
Specific Heat ◽  
Linear Equations ◽  
Adiabatic Calorimeter ◽  
Absolute Temperature ◽  
Large Temperature ◽  
Average Deviation ◽  
Specific Heats ◽  
New Type ◽  
The Individual ◽  
Theoretical Considerations

This paper contains the results of a long series of determinations of the specific heats of tungsten, molybdenum, and copper from − 20° to 500 °C.A new type of all-copper adiabatic calorimeter has been designed and used. The complete elimination of water from the calorimeter removed several sources of error and resulted in increased reliability and accuracy.Two entirely different methods were used in determining the specific heats. The usual "method of mixtures" was used to determine the mean specific heat for a large temperature change and was applied to all three metals over the entire range of temperature. The specific heat of copper was also determined for 5- or 10-degree intervals from − 5° to 110 °C. by heating the calorimeter electrically.It has been quite definitely shown that the specific heats of these metals over a temperature range as large as 0° to 500 °C. cannot be expressed as a linear function of the temperature. An equation of the form Cp = A + BT − C/T2 was arrived at from theoretical considerations and the constants determined empirically with the following results:—[Formula: see text]where the unit of heat is the 20-degree calorie and T is absolute temperature. The average deviation of the individual determinations from the values calculated by these equations was only about 0.1%.As a matter of convenience and for purposes of comparison, linear equations applicable over smaller ranges of temperature have also been given.

The specific heats of three paramagnetic salts at very low temperatures

1956 ◽  
Vol 237 (1210) ◽  
pp. 395-403 ◽  
Keyword(s):  
Specific Heat ◽  
Absolute Temperature ◽  
Magnesium Nitrate ◽  
Paramagnetic Resonance ◽  
Specific Heats ◽  
Ammonium Alum ◽  
Relaxation Measurements ◽  
Ferric Ammonium ◽  
The Absolute ◽  
Measured Specific Heat

The specific heats of three paramagnetic salts, neodymium magnesium nitrate, manganous ammonium sulphate and ferric ammonium alum, have been measured at temperatures below 1°K using the method of γ -ray heating. The temperature measurements were made in the first instance in terms of the magnetic susceptibilities of the salts, the relation of the susceptibility to the absolute temperature having been determined for each salt in earlier experiments. The γ -ray heatings gave the specific heat in arbitrary units. The absolute values of the specific heats were found by extrapolating the results of paramagnetic relaxation measurements at higher temperatures. The measured specific heat of neodymium magnesium nitrate is compared with the value calculated from paramagnetic resonance data, and good agreement is found.

Emerson's Atom and the Matter of Suffering

2009 ◽  
Vol 64 (1) ◽  
pp. 16-47
Author(s):  
Mark Noble
Keyword(s):  
Field Theory ◽  
Natural History ◽  
Classical Field Theory ◽  
Classical Field ◽  
The Other ◽  
History Of ◽  
The One ◽  
The Individual ◽  
Solid Bodies ◽  
Lines Of Force

This essay argues that Ralph Waldo Emerson's interest in the cutting-edge science of his generation helps to shape his understanding of persons as fluid expressions of power rather than solid bodies. In his 1872 "Natural History of Intellect," Emerson correlates the constitution of the individual mind with the tenets of Michael Faraday's classical field theory. For Faraday, experimenting with electromagnetism reveals that the atom is a node or point on a network, and that all matter is really the arrangement of energetic lines of force. This atomic model offers Emerson a technology for envisioning a materialized subjectivity that both unravels personal identity and grants access to impersonal power. On the one hand, adopting Faraday's field theory resonates with many of the affirmative philosophical and ethical claims central to Emerson's early essays. On the other hand, however, distributing the properties of Faraday's atoms onto the properties of the person also entails moments in which materialized subjects encounter their own partiality, limitation, and suffering. I suggest that Emerson represents these aspects of experience in terms that are deliberately discrepant from his conception of universal power. He presumes that if every experience boils down to the same lines of force, then the particular can be trivialized with respect to the general. As a consequence, Emerson must insulate his philosophical assertions from contamination by our most poignant experiences of limitation. The essay concludes by distinguishing Emersonian "Necessity" from Friedrich Nietzsche's similar conception of amor fati, which routes the affirmation of fate directly through suffering.

Specific heats of polymer powders by differential scanning calorimetry

1982 ◽  
Vol 60 (14) ◽  
pp. 1853-1856 ◽  
Author(s):  
Eva I. Vargha-Butler ◽  
A. Wilhelm Neumann ◽  
Hassan A. Hamza
Keyword(s):  
Differential Scanning Calorimetry ◽  
Specific Heat ◽  
Scanning Calorimetry ◽  
Temperature Range ◽  
Specific Heats ◽  
Powdered Form ◽  
Polymer Powders

The specific heats of five polymers were determined by differential scanning calorimetry (DSC) in the temperature range of 300 to 360 K. The measurements were performed with polymers in the form of films, powders, and granules to clarify whether or not DSC specific heat values are dependent on the diminution of the sample. It was found that the specific heats for the bulk and powdered form of the polymer samples are indistinguishable within the error limits, justifying the determination of specific heats of powders by means of DSC.

3. Results of Experiments on the Specific Heat of Certain Rocks

1845 ◽  
Vol 1 ◽  
pp. 373-374
Author(s):  
M. Regnault
Keyword(s):  
Specific Heat ◽  
Royal Society ◽  
Specific Heats

Professor Forbes observed that, in his communication to the Royal Society on the Conductivity of Soils for Heat, on the 20th December last (see Proceedings, page 343*), he had referred to the separation of the conductivity and specific heat, which are involved in the results of the thermometric experiments on subterranean temperature. In order to eliminate the effect of specific heat, M. Regnault of Paris (well known by his experiments on this subject) undertook, at the request of M. Elie de Beaumont, to ascertain the specific heats of the soils in which the different sets of thermometers are sunk.

The specific heats of copper, silver, and gold below 300 K

1987 ◽  
Vol 65 (9) ◽  
pp. 1104-1110 ◽  
Author(s):  
Douglas L. Martin
Keyword(s):  
Specific Heat ◽  
Debye Temperature ◽  
Temperature Scale ◽  
Specific Heats ◽  
Practical Temperature ◽  
Practical Temperature Scale

Specific-heat measurements on silver and gold in the 15–320 K range are reported and compared with earlier measurements on these metals. The present results together with recent measurements on copper (D. L. Martin, Rev. Sci. Instrum. 58, 639 (1987)) are analyzed in terms of the Debye temperature. The results suggest a negative anharmonic contribution to specific heat for silver and gold. Structure in the results for all three metals below 60 K is consistent with known imperfections in the International Practical Temperature Scale of 1968.

Queer Structures of Religious Feeling: What Time Is Now?

2017 ◽  
Author(s):  
Ann Pellegrini
Keyword(s):  
The Body ◽  
The Other ◽  
Individual Subject ◽  
Psychoanalysis And Religion ◽  
Time Out ◽  
Religious Feeling ◽  
The Times ◽  
The One ◽  
The Individual ◽  
Queer Temporality

This essay asks what psychoanalysis and religion might have to say to each other in view of Freud’s secular aspirations and queer theory’s temporal turn. Both queer temporality and psychoanalysis offer resources for understanding the multiple ways time coats, codes, and disciplines the body in secular modernity. This is so even though psychoanalysis is one of these disciplines. Nevertheless, the times of psychoanalysis are multiple. On the one hand, psychoanalysis quite frequently lays down a teleology in which the individual subject matures along a set pathway. On the other hand, this developmental imperative is at profound odds with psychoanalysis’s capacity to make room for the co-existence of past and present in ways that confound secular time’s forward march. This latter recognition—co-temporality—may even lay down routes for the cultivation of “counter-codes” (Foucault’s term), ways of living and experiencing and telling time out of sync with the linear logics of what José Muñoz has called “straight time.”

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