Effect of oxygen impurity in low concentrations on the heat capacity of solidified gases

1980 ◽  
Vol 38 (4) ◽  
pp. 349-351
Author(s):  
V. G. Manzhelii ◽  
Yu. A. Freiman ◽  
G. P. Chausov ◽  
V. V. Sumarokov
Author(s):  
Hwan Soo Dow ◽  
Moonkyong Na ◽  
Yeon Wook Jung ◽  
Seung Geun Jo ◽  
Jung Woo Lee

1985 ◽  
Vol 63 (7) ◽  
pp. 1568-1571 ◽  
Author(s):  
Hubert Daoust ◽  
Hoa Le Thanh ◽  
Pierre Ferland ◽  
Daniel St-Cyr

Heat capacities of polyelectrolytes in aqueous solutions have been measured at 25 °C using a Picker-type dynamic micro-calorimeter. The precision of the apparatus is such that it is possible to calculate the apparent molar heat capacity [Formula: see text] of the solute, even at high dilution. The polymers that were studied include polymethacrylic acid (PMAH) and polyacrylic acid (PAH), as well as its sodium salt and the sodium salt of the polystyrènesulfonate. For the salts, the results show that the value of [Formula: see text] decreases rapidly with dilution to low concentrations; this result is in perfect concordance with a relation derived from the theory of Lifson and Katchalsky. A study of the variation of [Formula: see text] at a constant concentration, with the extent of the neutralization of the acids PMAH and PAH has also been conducted. As has been shown previously, the chain of the PMAH undergoes a conformational transformation when the level of neutralization gets close to 25%. This transformation implies an increase of the value of [Formula: see text] [Journal translation]


2015 ◽  
Vol 69 (39) ◽  
pp. 1-9
Author(s):  
Y. Shiba ◽  
A. Teramoto ◽  
T. Suwa ◽  
K. Watanabe ◽  
S. Nishimura ◽  
...  

1987 ◽  
Vol 97 ◽  
Author(s):  
Cheryl M. Vaughan ◽  
William B. White

ABSTRACTOxygen uptake by the rare earth chalcogenides takes place through a series of ordered compounds. At high oxygen concentrations the distinct and nearly stoichiometric oxychalcogenides, Ln202X (X = S, Se, Te) appear. For the chalcogenides of the larger rare earths there appears an ordered oxygen-containing beta structure, Ln10X14OxX1-x (X = S, Se). The vibrational spectrum of the trigonal oxysulfide structure contains four infrared and four Raman bands (2 A2u + 2 Eu + 2 Alg + 2 Eg). Band wavenumbers across the La to Lu series vary linearly with unit cell volume. The Raman bands are sharp indicating a high degree of order in the intermediate compounds. The Raman bands of the beta structure are remarkably sharp indicating that this compound also has a highly ordered structure. Known data plus synthesis data are combined to form not-impossible phase diagrams for the larger rare earth sulfide systems. The effect of oxygen in both series of compounds is to produce small wavenumber shifts rather than high wavenumber oxygen impurity bands.


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