Specific Heat, Entropy and Free Energy of Gaseous Nitric Oxide Computed from the Spectroscopic Data

1934 ◽  
Vol 56 (11) ◽  
pp. 2229-2233 ◽  
Author(s):  
Enos E. Witmer
2020 ◽  
Vol 15 (12) ◽  
pp. 1934578X2098522
Author(s):  
Xian Zhang ◽  
Fa-Lei Zhang ◽  
Xing Wu ◽  
Ke Ye ◽  
Xiao Lv ◽  
...  

A previously undescribed polyketide (1) and 3 known analogs (2-4) were obtained from cultures of the potato endophytic fungus Aspergillus carneus. The structures were elucidated on the basis of extensive nuclear magnetic resonance spectroscopic data. The absolute configuration of 1 was further determined by electronic circular dichroism and optical rotation calculations. Compounds 1-4 showed moderate antifungal activity against plant pathogens. Compounds 1, 2, and 4 inhibited nitric oxide production in lipopolysaccharide-stimulated RAW264.7 cells, with half-maximal inhibitory concentration values of 13.36, 30.16, and 51.47 µM, respectively. Compound 4 showed effective antioxidant activity.


2000 ◽  
Vol 14 (11) ◽  
pp. 1179-1185
Author(s):  
B. I. SADOVNIKOV ◽  
N. G. INOZEMTSEVA ◽  
V. I. INOZEMTSEV

The thermodynamics of an inhomogeneous 1D Heisenberg chain with alternating classical and quantum spins is studied. The explicit expressions for the free energy, specific heat, thermal spin correlations and linear susceptibility are found.


1964 ◽  
Vol 17 (3) ◽  
pp. 269 ◽  
Author(s):  
P Lloyd

The anharmonic contribution to the free energy of a lattice is evaluated by means of a Bethe approximation. The approximation is accurate to within 3% for the model valuated by Maradudin, Flinn, and Coldwell� Horsfall. The anharmonic contribution to the specific heat at constant volume of a model of sodium is evaluated.The specific heat is found to increase as the temperature rises but the rate of increase is lower than the observed value


1995 ◽  
Vol 73 (7-8) ◽  
pp. 497-504 ◽  
Author(s):  
Ranjan Chaudhury

Several schemes based on the fermionic many-body approach and the boson-exchange approach are developed to calculate the free energy and specific heat for a marginal Fermi liquid in the normal and superconducting phase. The merits and demerits of these schemes are analyzed and compared. The origin of the failure of the simple Bardeen–Stephen formula is also highlighted. The analysis is carried out in light of some experiments.


2003 ◽  
Vol 806 ◽  
Author(s):  
Masahiro Kuno ◽  
Ludi A. Shadowspeaker ◽  
Jan Schroers ◽  
Ralf Busch

ABSTRACTThe thermodynamics of the bulk metallic glass forming Pd43Ni10Cu27P20 alloy were investigated with differential scanning calorimetry (DSC). The specific heat capacity of the undercooled liquid with respect to the crystalline mixture was measured in the DSC simultaneously with the enthalpy of crystallization over the entire supercooled liquid region. The enthalpy, entropy, and Gibbs free energy change between the liquid and the crystalline mixture was determined from the specific heat capacity data. The calculated enthalpy function closely matched the enthalpies of crystallization that were measured in the DSC, which verifies the validity of the thermodynamic model used. A small Gibbs free energy difference between undercooled liquid and crystalline mixture was found for decreasing temperature in Pd43Ni10Cu27P20 when compared to other glass forming alloys. This reflects a small driving force for crystallization when undercooling this alloy and is the main contributing factor for its high glass forming ability.


1965 ◽  
Vol 20 (12) ◽  
pp. 1553-1556
Author(s):  
F. Wagner ◽  
H. Koppe

Applying the variational principle of BOGOLIUBOV to calculate the free energy of a quantum system one does not get, automatically, physical meaningful results for entropy and specific heat. By using the temperature in the ansatz for the statistical operator as a variational parameter it is proved, that at any rate, the approximation expression for free energy has the properties of a thermodynamic function, that means, it leads to positive values for specific heat and entropy, and to a GIBBS—HELMHOLTZ equation for entropy and free energy.


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