scholarly journals X.—On the Economy of Heat in Expansive Machines, forming the Fifth Section of a Paper On the Mechanical Action of Heat

1853 ◽  
Vol 20 (2) ◽  
pp. 205-210 ◽  
Author(s):  
William John Macquorn Rankine
Keyword(s):  
Constant Temperature ◽  
Mechanical Action ◽  
The Body ◽  
Original Volume ◽  
Higher Temperature ◽  
The Difference ◽  
Lower Temperature ◽  
Quantity Of Heat

(39.) A machine working by expansive power consists essentially of a portion of some substance to which heat is communicated, so as to expand it, at a higher temperature, being abstracted from it, so as to condense it to its original volume, at a lower temperature. The quantity of heat given out by the substance is less than the quantity received; the difference disappearing as heat to appear in the form of expansive power.The heat originally received by the working body may act in two ways: to raise its temperature, and to expand it. The heat given out may also act in two ways: to lower the temperature, and to contract the body. Now, as the conversion of heat into expansive power arises from changes of volume only, and not from changes of temperature, it is obvious, that the proportion of the heat received which is converted into expansive power will be the greatest possible, when the reception of heat, and its emission, each take place at a constant temperature.

EFFECTS OF THYROIDECTOMY ON THE CHEQUERED WATER-SNAKE, NATRIX PISCATOR

1974 ◽  
Vol 60 (3) ◽  
pp. 517-NP ◽  
Author(s):  
J. P. THAPLIYAL ◽  
S. C. GUPTA ◽  
R. K. GARG
Keyword(s):  
Fatty Acids ◽  
Body Weight ◽  
Adipose Tissue ◽  
The Body ◽  
Thyroid Activity ◽  
Carbohydrate And Lipid Metabolism ◽  
Water Snake ◽  
Higher Temperature ◽  
The Difference ◽  
Lower Temperature

SUMMARY Thyroidectomy decreased the body weight and the height of the cells lining the sex-segment of the kidney of the Chequered Water-snake, Natrix piscator maintained at 30 °C; at 40 °C the liver, kidney and gonad were also affected. At the higher temperature, thyroidectomy influenced significantly protein, carbohydrate and lipid metabolism. At 30 °C, only a decrease in the rate of esterification of the free fatty acids in the liver and of their release from the adipose tissue was observed. The difference in the effect of thyroidectomy at 30 and 40 °C is explained by suggesting that thyroid activity was low in animals maintained at the lower temperature and high in those kept at the higher temperature.

INFLUENCE OF VARIATION IN ENVIRONMENTAL TEMPERATURE ON THE ACUTE TOXICITY OF RESERPINE AND CHLORPROMAZINE IN MICE

1960 ◽  
Vol 38 (1) ◽  
pp. 591-596 ◽  
Author(s):  
P. C. Dandiya ◽  
Gordon Johnson ◽  
E. A. Sellers
Keyword(s):  
Oxygen Consumption ◽  
Acute Toxicity ◽  
Environmental Temperature ◽  
Mechanisms Of Action ◽  
The Body ◽  
Time Of Death ◽  
Rapid Loss ◽  
Higher Temperature ◽  
The Difference ◽  
Maintain Body Temperature

The acute toxicity of chlorpromazine in mice is 18 times higher in an environment of 4 °C than in a thermoneutral environment of 30 °C. Under similar conditions the acute toxicity of reserpine increases about 1200 times. These findings confirm the earlier suggestion that these drugs cause hypothermia by different mechanisms of action. Increased acute toxicity of these drugs was also noticed at a higher temperature (36 °C).At 4 °C, after chlorpromazine, death occurred earlier than after reserpine. Reserpine produced a transient increase in oxygen consumption (in rats) which helped maintain body temperature but resulted in a more rapid loss of heat from the body. This would explain the difference in time of death and might explain the difference in ultimate mortality between the animals treated with these two drugs.

Mineralogical data on a multiple intrusion in the Rustenburg Layered Suite of the Bushveld Complex

1984 ◽  
Vol 48 (349) ◽  
pp. 469-480 ◽  
Author(s):  
G. Davies ◽  
R. G. Cawtnorn
Keyword(s):  
Bushveld Complex ◽  
The Body ◽  
Coarse Grained ◽  
Chemical Data ◽  
Ambient Temperatures ◽  
The North ◽  
Trace Element Chemistry ◽  
Higher Temperature ◽  
The Difference ◽  
North Western

AbstractMineralogical and chemical data are presented on an intrusion of a hypersthene gabbro body into coarse-grained noritic cumulates of the critical zone, which occurs at the margin of the Rustenburg Layered Suite of the Bushveld Complex. Two types of contact relations are found between the above two rock suites: (1) a clearly cross-cutting contact is observed on the southern margin of the hypersthene gabbro body close to the interface between the layered suite and the floor rocks; (2) a diffuse heterogeneous contact is found on the north-western limb of the body which is further into the complex. Field observations and chemical data suggest that, at the time of the hypersthene gabbro injection, the surrounding cumulates were above ambient temperatures. The difference in the contacts described above is probably related to the prevailing temperature gradient at the time of emplacement. The cumulate rocks further into the complex were at a higher temperature than those closer to the margin.Trace element chemistry and phase relations in the basalt tetrahedron indicate that the hypersthene gabbro is genetically unrelated to the cumulate rocks which it intrudes. The body probably represents an offshoot of the magma from which the upper zone of the Rustenburg Layered Suite crystallized.

INVESTIGATION OF THE CONTRIBUTION FOR THE NONCOLLINEAR CHANNEL OF THE F(2P3/2,2P1/2) + H2/D2 REACTIONS ON FOUR DIABATIC POTENTIAL ENERGY SURFACES

2012 ◽  
Vol 11 (03) ◽  
pp. 561-571 ◽  
Author(s):  
TING-XIAN XIE
Keyword(s):  
Potential Energy ◽  
Barrier Height ◽  
Cross Sections ◽  
Rate Constants ◽  
Potential Energy Surfaces ◽  
Collision Energy ◽  
Higher Temperature ◽  
The Difference ◽  
Lower Temperature ◽  
Energy Surfaces

We performed the nonadiabatic time-dependent wave packet calculation on the four diabatic potential energy surfaces, which have the different barrier height, to investigate the contribution of the noncollinear channel for the F (2P) + H2/D2 (v = j = 0) reactions. The reaction probabilities, integral cross-sections, and rate constants are presented. The results indicate that the probabilities as the function of the collision energy have an obvious translation. The reactive activity of the reactions comes from the noncollinear reactive channel. The bent barrier height would decrease the reactive activity. The integral cross-sections are in the order of AWS < LWA-5 < LWA-78 ≈ MASW, which is opposite to that of the bent barrier height. At the lower temperature, the difference of the rate constants is unambiguous. As the temperature increases, the difference reduces. At the higher temperature, the rate constants computed on the four potential energy surfaces are close.

scholarly journals The Floating of a Body on the Surface of a Liquid: A Synthesis

2021 ◽  
Vol 13 (1) ◽  
pp. 33
Author(s):  
Giancarlo Cavazzini
Keyword(s):  
Physical Interpretation ◽  
Mechanical Action ◽  
The Body ◽  
Correct Interpretation ◽  
Sign Changes ◽  
Material Volume ◽  
The Difference

The current physical interpretation of the phenomenon of floating of a body on the surface of a liquid - the so-called &rsquo;Archimedes&rsquo; Principle&rsquo; - is not correct. It is based on a assumption which is false, because it leads to contradict observed facts. A different physical interpretation is the correct interpretation, which is equivalent to the current one from the quantitative viewpoint, but significantly different from the physical viewpoint. When a volume of matter &ndash; a body - is immersed in a fluid, it &#39;loses&#39; its own weight, i.e., it is no longer home to the downward-directed mechanical action of which the volume is home when it is immersed in a vacuum. Therefore, a material volume immersed in a fluid does not host two mechanical actions - the &#39;weight&#39; of the volume itself, directed downwards, and the &#39;Archimedes&#39; force&#39;, directed upwards &ndash; but a single mechanical action. The intensity of this action is proportional to the volume of the body and to the difference in density between the matter which constitutes the body and the matter which constitutes the fluid. The direction of this action is related to the sign of the difference between the two values of density, reversing as the sign changes from positive to negative and vice-versa. Since the intensity of this mechanical action is proportional to the difference in density between the matter which constitutes the body and the matter which constitutes the fluid, there is no mechanical action &ndash; i.e., the mechanical action ceases &ndash; if there is equilibrium in density between the matter of the body and the matter of the fluid. This indicates that the main cause of this mechanical action is a physical disequilibrium between the matter which constitutes the body and the matter which constitutes the fluid, i.e., a physical disequilibrium/relationship between matter which is in contact.

INFLUENCE OF VARIATION IN ENVIRONMENTAL TEMPERATURE ON THE ACUTE TOXICITY OF RESERPINE AND CHLORPROMAZINE IN MICE

1960 ◽  
Vol 38 (6) ◽  
pp. 591-596 ◽  
Author(s):  
P. C. Dandiya ◽  
Gordon Johnson ◽  
E. A. Sellers
Keyword(s):  
Oxygen Consumption ◽  
Acute Toxicity ◽  
Environmental Temperature ◽  
Mechanisms Of Action ◽  
The Body ◽  
Time Of Death ◽  
Rapid Loss ◽  
Higher Temperature ◽  
The Difference ◽  
Maintain Body Temperature

The acute toxicity of chlorpromazine in mice is 18 times higher in an environment of 4 °C than in a thermoneutral environment of 30 °C. Under similar conditions the acute toxicity of reserpine increases about 1200 times. These findings confirm the earlier suggestion that these drugs cause hypothermia by different mechanisms of action. Increased acute toxicity of these drugs was also noticed at a higher temperature (36 °C).At 4 °C, after chlorpromazine, death occurred earlier than after reserpine. Reserpine produced a transient increase in oxygen consumption (in rats) which helped maintain body temperature but resulted in a more rapid loss of heat from the body. This would explain the difference in time of death and might explain the difference in ultimate mortality between the animals treated with these two drugs.

Study of averaged collision strength of non-Maxwellian distribution in plasma

2017 ◽  
Vol 31 (23) ◽  
pp. 1750213
Author(s):  
Jian He ◽  
Qingguo Zhang
Keyword(s):  
Temperature Region ◽  
Electronic Energy ◽  
Atmospheric Plasma ◽  
Maxwellian Distribution ◽  
Kappa Distribution ◽  
Collision Strength ◽  
Higher Temperature ◽  
The Difference ◽  
Lower Temperature ◽  
Lower Temperature Region

In this paper, kappa distribution of electronic energy is discussed for non-Maxwellian distribution. Taking silicon III 189.2 nm line in solar atmospheric plasma as an example, we discuss the kappa distribution and the Maxwellian distribution when temperature varies from [Formula: see text] K to [Formula: see text] K, and we calculate the averaged collision strengths of the kappa distribution and the Maxwellian distribution. Results indicate that the kappa distribution is close to the Maxwellian distribution with the increase of parameter [Formula: see text], and the difference of the averaged collision strength between the kappa distribution and the Maxwellian distribution is not very large in the higher temperature region from [Formula: see text] K to [Formula: see text] K, while that is large in the lower temperature region from [Formula: see text] K to [Formula: see text] K. This discussion will be significant in study of plasma quantitatively.

The dielectric temperature characteristic of additives modified barium titanate having core-shell structured ceramics

1995 ◽  
Vol 10 (11) ◽  
pp. 2770-2776 ◽  
Author(s):  
Yung Park ◽  
Yoonho Kim
Keyword(s):  
Temperature Characteristic ◽  
Chemical Inhomogeneity ◽  
Temperature Characteristics ◽  
Ferroelectric Transition ◽  
Curve Versus ◽  
Higher Temperature ◽  
The Difference ◽  
Lower Temperature ◽  
Grain Core ◽  
Ferroelectric Transition Temperature

The dielectric temperature characteristics and microstructures of BaTiO3-based ceramics sintered with additives such as Sm2O3, CeO2, and Bi2O3:Nb2O5 were investigated using TEM, XRD, and EDS. For a Sm2O3-modified BaTiO3 ceramic whose additives were uniformly distributed in grains, the ferroelectric transition temperature (Tc) was shifted to a lower temperature, while the transition temperatures (T1 and T2) were shifted to a higher temperature. The additions of CeO2 and Bi2O3: PbO to BaTiO3 formed the chemical inhomogeneity which was composed of grain core, grain shell, and concentration gradient region. The dielectric curve versus temperature of CeO2-modified BaTiO3 has the shape of one strong peak, whereas BaTiO3 ceramics sintered with Bi2O3:Nb2O5 exhibit the broad dielectric constant at the low temperature region and 130 °C ferroelectric transition peak. The dielectric temperature characteristics of additives modified BaTiO3 were determined in terms of the chemical inhomogeneity and stress induced by the difference of the unit cell volume between grain core and grain shell.

scholarly journals What Is the Real Clausius Statement of the Second Law of Thermodynamics?

Entropy ◽  
2019 ◽  
Vol 21 (10) ◽  
pp. 926 ◽  
Author(s):  
Ti-Wei Xue ◽  
Zeng-Yuan Guo
Keyword(s):  
Second Law Of Thermodynamics ◽  
Fundamental Principle ◽  
Quantitative Relation ◽  
Second Law ◽  
The Real ◽  
Average Temperature ◽  
Temperature Method ◽  
Higher Temperature ◽  
The Difference ◽  
Lower Temperature

In this paper, we first analyze the difference between the second law of thermodynamics and the laws in other disciplines. There are some phenomena in other disciplines similar to the Clausius Statement of the second law, but none of them has been accepted as the statement of a certain law. Clausius’ mechanical theory of heat, published in the nineteenth century, is then introduced and discussed in detail, from which it is found that Clausius himself regarded “Theorem of the equivalence of the transformation of heat to work, and the transformation of heat at a higher temperature to a lower temperature”, rather than “Heat can never pass from a colder to a warmer body without some other change”, as the statement of the second law of thermodynamics. The latter is only laid down as the fundamental principle for deriving the theorem of the equivalence of transformations. Finally, based on the theorem of the equivalence of transformations and the average temperature method, a general quantitative relation among the heat, the work, and the temperatures is obtained for arbitrary cycles, which is thus recommended as an alternative mathematic expression of the second law. Hence, the theorem of the equivalence of transformations is the real Clausius Statement of the second law of thermodynamics.

Using Growth Kinetics for Nanoengineering of Si-Ge Surfaces

1998 ◽  
Vol 533 ◽  
Author(s):  
I. Goldfarb ◽  
G. A. D. Briggs
Keyword(s):  
Three Dimensional ◽  
Self Assembling ◽  
Deposition Parameters ◽  
Temperature Ranges ◽  
Nucleation And Growth Mechanisms ◽  
Temperature Deposition ◽  
Higher Temperature ◽  
The Difference ◽  
Lower Temperature ◽  
Post Deposition

AbstractIn this work we explore how various growth characteristics of Ge on Si(001) can be used to fabricate structures for potential nanodevices. In the first example, the self-assembling tendency of germanium for three-dimensional islanding on Si(001) is considered, e.g. for application in devices based on quantum dots and wires. We aimed at achieving a detailed understanding of dot nucleation and growth mechanisms from germane. By controlling the deposition parameters, such as the germane pressure and substrate temperature, arrays of dots and antidots can be created on the grown surface, and further modified by post-deposition anneals. While lower temperature deposition leads to randomly distributed dots (i.e. small and coherent three-dimensional clusters with pyramidal shapes), a higher temperature deposition results in formation of antidots (i.e. pyramidal pits), which, in turn, are gradually replaced by the clusters, if the deposition is allowed to continue. The difference is caused by the different hydrogen behaviour at the respective temperature ranges. The germanium tendency to incorporate preferentially at the step and island edges is another beneficial property, which can be used to align the dots along step edges, creating wires rather than dots, or to fabricate ultrasmall Si-Ge heterojunctions, of a less than 10 nanometer size.

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