scholarly journals The specific heats of air, steam, and carbon dioxide

1923 ◽  
Vol 103 (720) ◽  
pp. 183-184 ◽  
Keyword(s):  
Carbon Dioxide ◽  
Title I ◽  
Low Temperatures ◽  
Close Agreement ◽  
The Other ◽  
British Association ◽  
Specific Heats

In a recent number is a criticism under the above title by Sir R. T. Glazebrook, of some figures given by me in a paper with the same title. I am accused of not giving Holborn and Henning's own figures, because I State that part of my curve is filled in from the researches of Swann, and of Holborn and Henning. As Swann and Holborn and Henning are not in agreement, it seems evident that one set figures cannot be used without some adjustment to the other set. These discrepancies were dealt with by the British Association Committee (of which Sir R. T. Glazebrook later became a member) in their 1908 Report, and the figures I give are in fairly close agreement with theirs for the low temperatures. I State in my paper (p. 492) that I find Holborn and Henning about 7½ percent. too low at 800°C. for air and steam, and I assume that the same error applies to the carbon dioxide. (Prof. Callendar suggests their error may be as much as 10 per cent. at 1400°C.) I have, therefore, distributed this error over the range for which I have used Holborn and Henning's figures. On this account it may be anticipated "that the figures at the higher temperatures are higher than the corresponding figures due to Holborn." I believe it is usual, when quoting the results of other workers, to attach their names to the figures quoted; this I have not done.

The Specific Heat of Carbon Dioxide—Correction

1928 ◽  
Vol 24 (2) ◽  
pp. 290-290
Author(s):  
W. H. McCrea
Keyword(s):  
Carbon Dioxide ◽  
Specific Heat ◽  
Low Temperatures ◽  
Molecular Form ◽  
Specific Heats ◽  
Heat Curve

In a recent paper in these Proceedings the writer suggested the possibility of a transition from one molecular form to another in CO2. The suggestion is embodied in the equation (10) and the resulting specific heats for low temperatures given. He greatly regrets that it was not till after those results were published that he found they gave a high and altogether impossible maximum in the specific heat curve for higher temperatures before it returns to the neighbourhood of the unmodified curve Cv′.

The Turnover in Normal Dogs of Prothrombin and Its Fragments; Effect of Induced Intravascular Coagulation

1979 ◽  
Vol 42 (02) ◽  
pp. 548-555 ◽  
Author(s):  
Charles A Owen ◽  
Kenneth G Mann ◽  
Frederic C McDuffie
Keyword(s):  
Close Agreement ◽  
Blood Stream ◽  
The Other ◽  
Normal Adult ◽  
Capillary Barrier ◽  
Prothrombin Fragment ◽  
Intravascular Coagulation ◽  
Dog Brain

SummaryWhen 125I-labeled canine prothrombin was given to normal adult dogs intravenously, it was calculated that 240% of the plasma prothrombin crossed the capillary barrier per day, 410% of the interstitial prothrombin returned to the blood stream daily, and 79% of the plasmatic prothrombin was catabolized per day. These data are in close agreement with those observed for bovine prothrombin in calves by Takeda (1970).When derived from normal dog prothrombin, prethrombin-1 is a mixture of 2 polypeptides, one larger than the other, and both present in about equal amounts. The longer peptide, “prethrombin-1-long,” was catabolized twice as fast as prothrombin, and the shorter, “prethrombin-1-short,” 4 times faster. Prothrombin fragment-1 was catabolized by the normal dog still more rapidly.The catabolism of prothrombin was not accelerated in 3 dogs receiving continuous infusions of a thromboplastic emulsion of dog brain. Nor was the level of prothrombin in their plasma remarkably altered.

scholarly journals Catalytic Conversion of n-C7 Asphaltenes and Resins II into Hydrogen Using CeO2-Based Nanocatalysts

Nanomaterials ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1301
Author(s):  
Oscar E. Medina ◽  
Jaime Gallego ◽  
Sócrates Acevedo ◽  
Masoud Riazi ◽  
Raúl Ocampo-Pérez ◽  
...  
Keyword(s):  
Hydrogen Production ◽  
Low Temperatures ◽  
Gaseous Mixture ◽  
H2 Production ◽  
The Other ◽  
Hydrogen Release ◽  
Catalytic Gasification ◽  
Three Samples ◽  
Main Decomposition ◽  
Catalytic Capacity

This study focuses on evaluating the volumetric hydrogen content in the gaseous mixture released from the steam catalytic gasification of n-C7 asphaltenes and resins II at low temperatures (<230 °C). For this purpose, four nanocatalysts were selected: CeO2, CeO2 functionalized with Ni-Pd, Fe-Pd, and Co-Pd. The catalytic capacity was measured by non-isothermal (from 100 to 600 °C) and isothermal (220 °C) thermogravimetric analyses. The samples show the main decomposition peak between 200 and 230 °C for bi-elemental nanocatalysts and 300 °C for the CeO2 support, leading to reductions up to 50% in comparison with the samples in the absence of nanoparticles. At 220 °C, the conversion of both fractions increases in the order CeO2 < Fe-Pd < Co-Pd < Ni-Pd. Hydrogen release was quantified for the isothermal tests. The hydrogen production agrees with each material’s catalytic activity for decomposing both fractions at the evaluated conditions. CeNi1Pd1 showed the highest performance among the other three samples and led to the highest hydrogen production in the effluent gas with values of ~44 vol%. When the samples were heated at higher temperatures (i.e., 230 °C), H2 production increased up to 55 vol% during catalyzed n-C7 asphaltene and resin conversion, indicating an increase of up to 70% in comparison with the non-catalyzed systems at the same temperature conditions.

scholarly journals On the measurement of the ratio of the specific heats using small volumes of gas.—The ratios of the specific heat of air and of hydrogen at atmospheric pressure and a temperatures between 20°C. and —183°C

1925 ◽  
Vol 107 (743) ◽  
pp. 510-543 ◽  
Keyword(s):  
Systematic Error ◽  
Low Temperatures ◽  
Room Temperature ◽  
Expansion Chamber ◽  
Small Vessels ◽  
Specific Heats ◽  
Large Expansion ◽  
Before And After ◽  
The One ◽  
Chamber Capacity

Introduction .—In nearly all the previous determinations of the ratio of the specific heats of gases, from measurements of the pressures and temperature before and after an adiabatic expansion, large expansion chambers of fror 50 to 130 litres capacity have been used. Professor Callendar first suggests the use of smaller vessels, and in 1914, Mercer (‘Proc. Phys. Soc.,’ vol. 26 p. 155) made some measurements with several gases, but at room temperature only, using volumes of about 300 and 2000 c. c. respectively. He obtained values which indicated that small vessels could be used, and that, with proper corrections, a considerable degree of accuracy might be obtained. The one other experimenter who has used a small expansion chamber, capacity about 1 litre, is M. C. Shields (‘Phys. Rev.,’ 1917), who measured this ratio for air and for hydrogen at room temperature, about 18° C., and its value for hydroger at — 190° C. The chief advantage gained by the use of large expansion chambers is that no correction, or at the most, a very small one, has to be made for any systematic error due to the size of the containing vessels, but it is clear that, in the determinations of the ratio of the specific heats of gases at low temperatures, the use of small vessels becomes a practical necessity in order that uniform and steady temperature conditions may be obtained. Owing, however, to the presence of a systematic error depending upon the dimensions of the expansion chamber, the magnitude of which had not been definitely settled by experiment, the following work was undertaken with the object of investigating the method more fully, especially with regard to it? applicability to the determination of this ratio at low temperatures.

STUDIES ON THE BACTERIAL OXIDATION OF 2,3-BUTANEDIOL AND RELATED COMPOUNDS

1944 ◽  
Vol 22b (5) ◽  
pp. 140-153 ◽  
Author(s):  
R. Y. Stanier ◽  
Sybil B. Fratkin
Keyword(s):  
Carbon Dioxide ◽  
Aeromonas Hydrophila ◽  
The Other ◽  
Bacterial Oxidation ◽  
Aerobacter Aerogenes ◽  
Aerobic Conditions ◽  
Related Compounds

Aerobacter aerogenes, Aerobacillus polymyxa, and Aeromonas hydrophila, representatives of the three genera characterized by a butanediol fermentation, can all oxidize 2,3-butanediol under aerobic conditions. The configuration of the 2,3-butanediol has considerable bearing on its decomposability: Aerobacter aerogenes is inactive on the l-isomer, but attacks both meso- and d-isomers; Aeromonas hydrophila attacks the meso-isomer but not the l- and probably not the d-isomer; Aerobacillus polymyxa can oxidize both l- and meso-2,3-butanediol, but the rate with the former is many times greater than with the latter. Aerobacter aerogenes oxidizes both 2,3-butanediol and acetoin to carbon dioxide and water, a large part of the substrate being simultaneously assimilated. The other two organisms oxidize 2,3-butanediol to acetoin, but can further oxidize the acetoin thus formed only very slowly, if at all. Both Aerobacter aerogenes and Aerobacillus polymyxa are unable to attack 1,3-butanediol, 2-methyl-1,2-propanediol and 1,2-ethancdiol. However they can oxidize 1,2-propanediol to acetol.

Toxæmia in the Etiology of Mental Disease. a Discussion opened

1902 ◽  
Vol 48 (202) ◽  
pp. 434-450 ◽  
Author(s):  
T. S. Clouston
Keyword(s):  
Nerve Cell ◽  
General Trend ◽  
Mental Disease ◽  
The Other ◽  
British Association ◽  
Younger Men ◽  
Full Knowledge ◽  
The Subject ◽  
Definition Of ◽  
Do So

Dr. Clouston said that when he suggested toxæmia to the secretary as a suitable subject for a discussion at this meeting he had not intended to be the first speaker, because his object was to bring out more fully the views of the younger members who had recently committed themselves so strongly to the toxæmic and bacterial etiology of insanity, and so to get light thrown on some of the difficulties which he and others had felt in applying this theory to many of their cases in practice. It was not that he did not believe in the toxic theory as explaining the onset of many cases, or that he under-rated its importance, but that he could not see how it applied so universally or generally as some of the modern pathological school were now inclined to insist on. He knew that it was difficult for those of the older psychological and clinical school to approach the subject with that full knowledge of recent bacteriological and pathological doctrine which the younger men possessed, or to breathe that all-pervading pathological atmosphere which they seemed to inhale. He desired to conduct this discussion in an absolutely non-controversial and purely scientific spirit. To do so he thought it best to put his facts, objections, and difficulties in a series of propositions which could be answered and explained by the other side. He thought it important to define toxæmia, but should be willing to accept Dr. Ford Robertson's definition of toxines, viz., “Substances which are taken up by the (cortical nerve) cell and then disorder its metabolism.” He took the following extracts from his address at the Cheltenham meeting of the British Association (1) as representing Dr. Ford Robertson's views and the general trend of much investigation and hypothesis on the Continent.

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