The Effect of Solvent Change on the Standard Chemical Potential of Electrolytes. Comparison of Vapor Pressure and E.M.F. Data for HC1, NaOH and Kwin the System Dioxane-Water1

1958 ◽  
Vol 80 (15) ◽  
pp. 3844-3846 ◽  
Author(s):  
George Baughman ◽  
Ernest Grunwald
Keyword(s):  
Vapor Pressure ◽  
Chemical Potential ◽  
Effect Of Solvent ◽  
Standard Chemical Potential

scholarly journals Kovats retention index-boiling point relationship of 2-phenyl-2-alkyl-acetonitriles on stationary phases of different polarity

2005 ◽  
Vol 11 (2) ◽  
pp. 55-58 ◽  
Author(s):  
Dusan Mijin ◽  
Dusan Antonovic
Keyword(s):  
Stationary Phase ◽  
Retention Index ◽  
Boiling Point ◽  
Chemical Potential ◽  
Stationary Phases ◽  
Kovats Retention Index ◽  
Standard Chemical Potential ◽  
Relationship Of ◽  
Kováts Retention Index ◽  
Methylene Group

Linear and reciprocial Kovats retention index-boiling point relationships known from the literature were used to study the Kovats retention index-boiling point dependence of 2-phenyl-2-alkylacetonitriles on stationary phases of different polarity (OV-17, OV-210 and OV-225). The standard chemical potential of the partitioning of one methylene group of an n-alkane for the stationary phase was calculated and compared with available literature data.

Partially miscible liquid systems: The density, change of volume on mixing, vapor pressure, surface tension, and viscosity in the system: aniline–hexane

1968 ◽  
Vol 46 (14) ◽  
pp. 2399-2407 ◽  
Author(s):  
A. N. Campbell ◽  
E. M. Kartzmark ◽  
S. C. Anand ◽  
Y. Cheng ◽  
H. P. Dzikowski ◽  
...  
Keyword(s):  
Surface Tension ◽  
Vapor Pressure ◽  
Chemical Potential ◽  
Density Change ◽  
Solution Temperature ◽  
Critical Solution Temperature ◽  
Pressure Surface ◽  
Anomalous Viscosity ◽  
Tension Properties ◽  
Liquid Systems

The following properties have been investigated experimentally: density, change of volume on mixing, vapor pressure, surface tension, and viscosity, at temperatures above and below the critical solution temperature. The question at issue is: How does the chemical potential, or any property dependent on chemical potential, change, at constant temperature, over a range of composition, just above the critical solution temperature? In the present case, the vapor pressure and surface tension, properties directly dependent on chemical potential, are constant within the range of experimental accuracy (which, however, may not be sufficient) over a range of concentration. The viscosity is complicated by the occurrence of anomalous viscosity. The change of volume on mixing is negative, and this is usually associated with compound formation. In all other systems investigated by us, except the system triethylamine–water, ΔV is positive. We have shown elsewhere, however, that a very stable chemical compound is formed between water and triethylamine.

Chemico-Physical Causes of Radiation-Induced “Long Cell” Action Corrosion in Water Cooled Reactors

2010 ◽  
Author(s):  
Genn Saji
Keyword(s):  
Chemical Potential ◽  
Cooling System ◽  
Radiation Chemistry ◽  
Potential Difference ◽  
Equilibrium Potential ◽  
Corrosion Mechanism ◽  
Hydrated Electrons ◽  
Standard Chemical Potential ◽  
Radiation Induced ◽  
Reactor Types

In the previous overview papers [1, 2], the author has identified that ‘long cell action’ corrosion plays a pivotal role in practically all unresolved corrosion issues, irrespective of reactor types and operation. In trying to confirm the existence of radiation-induced ‘long-cell’ action (macro) corrosion cell in the primary cooling system of LWRs, the author attempted to theoretically reproduce the electrochemical potential difference demonstrated during experiments at the INCA Loop in Sweden and the NRI-Rez Loop in the Czech Republic [3, 4]. By performing a radiation chemistry kinetics study combined with electrochemistry calculations, the hydrated electrons, e−aq, reacting mainly with stable molecules, are found to be responsible for inducing a large portion of the potential difference both in the PWR and BWR water chemistry environment. Considering large uncertainties, the author used the standard equilibrium potential as a fitting parameter in the previous studies [3, 4]. The standard chemical potential of the hydrated electron estimated from the fitting parameter is far less than the generally accepted value of 2.86 V. In order to resolve the large discrepancy between the generally accepted values and the estimation from the fitting parameter, the author has developed a ‘mixed’ radiation-electrochemistry formalism, which enables theoretical reconstruction of the observed potential differences more clearly. The previous verifications are updated by using this approach. Through these studies, the author has confirmed the existence of the ‘long cell’ action corrosion mechanism existing in the water-cooled reactors.

Delayed Inoculative Freezing of Insects

1963 ◽  
Vol 95 (11) ◽  
pp. 1190-1202 ◽  
Author(s):  
R. W. Salt
Keyword(s):  
Fine Structure ◽  
Vapor Pressure ◽  
Body Fluid ◽  
Rate Increase ◽  
Chemical Potential ◽  
Structural Characteristics ◽  
Detergent Solution ◽  
Vapor Pressure Difference ◽  
Ice Surface ◽  
Inoculative Freezing

AbstractInoculative freezing of insects is distinguished from nucleative freezing and is treated from the standpoint of the delays observed in freezing. On the assumption that the fine structure of the cuticle regulates the penetration or growth of external ice into the insect's body, the cuticle was experimentally altered by soaking, boiling, and immersion in strong detergent solution. Soaking was of doubtful effectiveness, whereas boiling and detergent hastened inoculation, Detergent also caused many insects to freeze when the contact water froze, with no delay. Rate of inoculation of untreated larvae was directly proportional to the area in contact with ice, and inversely proportional to temperature down to −10 °C. No further rate increase took place down to −15 °C, possibly because the vapor pressure difference between ice and supercooled body fluid does not change appreciably in this temperature range. Larvae froze more rapidly when they had already been frozen and thawed once or twice. No relation between inoculation rate and rate of water loss in a dry atmosphere could be established.The freezing of water in extremely small spaces is discussed and related to the process of inoculative freezing. Probable pathways of ice growth through the cuticle are considered in relation to known structural characteristics and the results of the present experiments. Two hypotheses are proposed to account for the observed delays in freezing, but neither is wholly satisfactory. The first postulates that the outer extremities of the pathways, through the epicuticle, are hydrophobic and contain air which temporarily separates contact moisture from pore liquids. After freezing of the contact moisture a vapor pressure differential results in a net flow of vapor outwards, the vapor freezing on the ice and building inwards until the ice front touches liquid in a space large enough to allow freezing. This hypothesis assumes the existence of at least one pathway large enough to support ice penetration without hindrance caused by restricted size. The second hypothesis assumes that no such unrestricted pathways are present, all being inadequate in size. Differences in chemical potential between ice and liquid cause pore liquids to move outwards to the contacting ice surface and accrete on its

On thermodynamic equilibrium of carbon deposition from gaseous C-H-O mixtures: updating for nanotubes

2017 ◽  
Vol 33 (3) ◽  
Author(s):  
Zdzisław Jaworski ◽  
Barbara Zakrzewska ◽  
Paulina Pianko-Oprych
Keyword(s):  
Carbon Deposition ◽  
Chemical Potential ◽  
Quantitative Description ◽  
Extensive Literature ◽  
Ternary Diagrams ◽  
Filamentous Carbon ◽  
Standard Chemical Potential ◽  
Multi Walled Carbon Nanotubes ◽  
Temperature Levels ◽  
Walled Carbon Nanotubes

AbstractExtensive literature information on experimental thermodynamic data and theoretical analysis for depositing carbon in various crystallographic forms is examined, and a new three-phase diagram for carbon is proposed. The published methods of quantitative description of gas-solid carbon equilibrium conditions are critically evaluated for filamentous carbon. The standard chemical potential values are accepted only for purified single-walled and multi-walled carbon nanotubes (CNT). Series of C-H-O ternary diagrams are constructed with plots of boundary lines for carbon deposition either as graphite or nanotubes. The lines are computed for nine temperature levels from 200°C to 1000°C and for the total pressure of 1 bar and 10 bar. The diagram for graphite and 1 bar fully conforms to that in (Sasaki K, Teraoka Y. Equilibria in fuel cell gases II. The C-H-O ternary diagrams. J Electrochem Soc 2003b, 150: A885–A888). Allowing for CNTs in carbon deposition leads to significant lowering of the critical carbon content in the reformates in temperatures from 500°C upward with maximum shifting up the deposition boundary O/C values by about 17% and 28%, respectively, at 1 and 10 bar.

scholarly journals Relations between absorption, emission, and excited state chemical potentials from nanocrystal 2D spectra

2021 ◽  
Vol 7 (22) ◽  
pp. eabf4741
Author(s):  
Jisu Ryu ◽  
Samuel D. Park ◽  
Dmitry Baranov ◽  
Iva Rreza ◽  
Jonathan S. Owen ◽  
...  
Keyword(s):  
Excited State ◽  
Single Molecule ◽  
Chemical Potential ◽  
Emission Spectra ◽  
Optical Methods ◽  
Chemical Potential Difference ◽  
Absorption And Emission ◽  
Absorption And Emission Spectra ◽  
Standard Chemical Potential ◽  
Size Dispersion

For quantum-confined nanomaterials, size dispersion causes a static broadening of spectra that has been difficult to measure and invalidates all-optical methods for determining the maximum photovoltage that an excited state can generate. Using femtosecond two-dimensional (2D) spectroscopy to separate size dispersion broadening of absorption and emission spectra allows a test of single-molecule generalized Einstein relations between such spectra for colloidal PbS quantum dots. We show that 2D spectra and these relations determine the thermodynamic standard chemical potential difference between the lowest excited and ground electronic states, which gives the maximum photovoltage. Further, we find that the static line broadening from many slightly different quantum dot structures allows single-molecule generalized Einstein relations to determine the average single-molecule linewidth from Stokes’ frequency shift between ensemble absorption and emission spectra.

QUESTIONS AND PROBLEMS OF MATHEMATICAL MODELING QUA NONEQUILIBRIUM OF COMBUSTION PROCESSES

2020 ◽  
Vol 8 (4) ◽  
pp. 31-38
Author(s):  
E.V. Radkevich ◽  
◽  
N.N. Yakovlev ◽  
O.A. Vasil’eva ◽  
◽  
...  
Keyword(s):  
Phase Space ◽  
Chemical Potential ◽  
Blow Up ◽  
Local Equilibrium ◽  
Combustion Process ◽  
Passive Component ◽  
Component Mixture ◽  
Total Differential ◽  
Standard Chemical Potential ◽  
Component Velocity

On the basis of thermodynamic analysis, new mathematical models of the combus- tion process (thermal theory) and vibrational combustion are constructed. A global inhomo- geneity of the system can be described as an inhomogeneous distribution of the enthalpy over a two-component mixture. In this case, for the combustion process in the phase space of the variables (%, P, T, n, S, E), an increase in the enthalpy is not a total differential. An increase in the enthalpy is a total differential on the local equilibrium manifold (a laminar combustion process). These two assertions, which allow one to single out in the phase space the corre- sponding adiabatic of the combustion process (the Hugoniot adiabatic) and the equation for the entropy, close the classical mathematical model of the combustion process. The above numerical experiments show that two regimes of the combustion process (deflagration and detonation) depend on the structure of the standard chemical potential Moreover, a control of the passive component velocity at the inlet results in (depending on the structure of the standard chemical potential) high-frequency oscillations, which are responsible for a blow-up.

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