Partial Molar Quantities and Excess Quantities

1. When female blowflies are fed unlimited quantities of ‘protein’ (marmite and milk) and sugar solutions, their corpora allata (c.a.) volumes increase before and decrease during yolk formation in normal females but hypertrophy in ovariectomized flies. If fed sugar solution alone, the ovaries of the flies do not mature and the c.a. in both normal and ovariectomized females remain small. The interpretation and control of these variations in volume were investigated. 2. When ovariectomized or normal females are fed ‘protein’, their c.a. volumes increase in proportion to the quantity consumed. When ‘protein’ is removed from the diet, the c.a. decrease in size. The c.a. respond similarly in both types of fly up to the stage at which yolk is normally deposited. If a further quantity of ‘protein’ is ingested at this stage, the c.a. of normal females increase slightly in volume and then decrease during yolk deposition. But the c.a. of ovariectomized females hypertrophy before decreasing in size. 3. The decrease in c.a. volume during yolk formation may be virtually eliminated by forcing the flies to ingest excess quantities of ‘protein’ during this phase. 4. The graded response of the c.a. to ‘protein’ consumption suggests that fluctuations of c.a. volume represent variations in activity induced (proportionately) by ‘protein’ metabolites in the blood (there is no accumulation of ‘protein’ in the gut). The decrease in size during yolk formation is due to the removal of ‘protein’ metabolites by the ovaries for the purpose of yolk formation. In ovariectomized flies, these yolk precursors accumulate in the blood causing the c.a. to become hyper-active as indicated by hypertrophy. 5. The responses of the c.a. to ‘protein’ consumption do not appear to be unduly affected by denervation, cutting of the nervi oesophagi or of the cardiac-recurrent nerve. 6. There is slight evidence that the corpus cardiacum is able to store c.a. hormone.

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New possibilities of applications of the Barker quasi-lattice theory. Prediction of gE and hE of binary systems whose one component is formed by n-alkanes

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19791698 ◽

1979 ◽

Vol 44 (6) ◽

pp. 1698-1714 ◽

Cited By ~ 7

Author(s):

Vladimír Dohnal ◽

Robert Holub ◽

Jiří Pick

Keyword(s):

Aromatic Hydrocarbons ◽

Lattice Theory ◽

Binary Systems ◽

Derived Relations ◽

Orientation Effects ◽

The Given ◽

Derivatives Of ◽

Arbitrary Component ◽

Excess Quantities ◽

Good Agreement

For binary systems of the type an arbitrary component + n-alkane we derived relations, on the basis of the Barker theory and on the basis of the group contribution concept, for predicting gE and hE from one system to another when the n-alkane length is changed. To carry out the prediction it is not necessary to evaluate any adjustable parameters. The developed method was tested using a large number of different systems covering alcohols, amines, ketones, esters, chlorinated derivatives of hydrocarbons, aromatic hydrocarbons and n-alkanes from n-pentane to n-hexadecane. The results of predictions are in very good agreement with experimental data in the cases, when the n-alkanes involved are not longer than n-decane. Systematic regular deviations in hE in the cases, when at least one of n-alkanes involved is longer, can be explained by the presence of orientation effects in the pure longer n-alkanes. The correction suggested by us for these effects improves considerably results obtained. The developed method appears to be suitable for the systematic prediction of excess quantities of systems of the given type and represents an effective test of the Barker theory.

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Thermodynamic excess quantities of ternary Au–Co–Pd melts by computer-aided Knudsen cell mass spectrometry

Thermochimica Acta ◽

10.1016/j.tca.2009.05.010 ◽

2009 ◽

Vol 495 (1-2) ◽

pp. 22-27

Author(s):

Josef Tomiska

Keyword(s):

Mass Spectrometry ◽

Cell Mass ◽

Knudsen Cell ◽

Computer Aided ◽

Cell Mass Spectrometry ◽

Knudsen Cell Mass Spectrometry ◽

Excess Quantities ◽

Thermodynamic Excess

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Prediction of multicomponent liquid adsorption using excess quantities

Journal of Colloid and Interface Science ◽

10.1016/j.jcis.2004.01.077 ◽

2004 ◽

Vol 275 (1) ◽

pp. 90-96 ◽

Cited By ~ 8

Author(s):

Grit Kalies ◽

Peter Bräuer ◽

Ulf Messow

Keyword(s):

Liquid Adsorption ◽

Excess Quantities

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Über die extrem hohe thermodynamische Stabilität von Pd-Th-Legierungen / On the Extremely High Thermodynamic Stability of Pd-Th Alloys

Zeitschrift für Naturforschung A ◽

10.1515/zna-1979-0409 ◽

1979 ◽

Vol 34 (4) ◽

pp. 464-468 ◽

Cited By ~ 1

Author(s):

H.-J. Schaller

Keyword(s):

Excess Free Energy ◽

Palladium Alloys ◽

Electronic Interactions ◽

Thorium Concentration ◽

Valence Electrons ◽

High Thermodynamic Stability ◽

Work Functions ◽

The Difference ◽

Excess Quantities ◽

Mixing Behaviour

The thermodynamic properties of Pd-Th solid solutions containing up to 16 at.% Th have been determined by the e.m.f. method between 700 and 800 °C with CaF2 solid electrolyte cells. The mixing behaviour of the alloys is characterized by extreme negative deviations from ideality, up to -410 kJ/mol for the partial molar excess free energy of Thorium. The extraordinary stability is attributed to electronic interactions brought about by the transfer of the Thorium valence electrons to the electron gas of the alloy. At vanishing Thorium concentration the resulting bonding contribution to the thermodynamic excess quantities is determined by the difference of the Fermi energies of the pure components, approximately equal to the difference of the work functions. Including the lattice distortion as a small additional effect, the mixing behaviour of these and other palladium alloys can be well described

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