scholarly journals Effects of degree of dissociation of acid used on hydrolytic durability of ceramic primer

2014 ◽  
Vol 33 (5) ◽  
pp. 614-620 ◽  
Author(s):  
Naoko AOKI ◽  
Suguru KIMOTO ◽  
Hideki TANIMURA ◽  
Norihiro NISHIYAMA ◽  
Masahiro AIDA
Keyword(s):  
Degree Of Dissociation ◽  
Hydrolytic Durability

Phase composition, structure, and hydrolytic durability of glasses in the Na2O-Al2O3-(Fe2O3)-P2O5 system at replacement of Al2O3 by Fe2O3

2015 ◽  
Vol 57 (4) ◽  
pp. 348-355 ◽  
Author(s):  
S. V. Stefanovsky ◽  
O. I. Stefanovskaya ◽  
S. E. Vinokurov ◽  
S. S. Danilov ◽  
B. F. Myasoedov
Keyword(s):  
Phase Composition ◽  
Composition Structure ◽  
P2o5 System ◽  
Hydrolytic Durability

DISSOCIATION IN ANOREXIA NERVOSA AND BULIMIA NERVOSA

1994 ◽  
Vol 22 (4) ◽  
pp. 385-392 ◽  
Author(s):  
John F. Schumaker ◽  
William G. Warren ◽  
Gwenda S. Schreiber ◽  
Craig C. Jackson
Keyword(s):  
Anorexia Nervosa ◽  
Bulimia Nervosa ◽  
Future Research ◽  
Control Group ◽  
Degree Of Dissociation ◽  
Eating Disordered ◽  
Control Subjects ◽  
Significant Difference

The present study employed the Riley Questionnaire of Experiences of Dissociation in order to assess degree of dissociation in females diagnosed with anorexia nervosa and bulimia. The subjects consisted of 26 anorexic and 18 bulimic females, and a non eating-disordered control group of 22 females. Results indicated that eating disordered subjects, considered together, had significantly higher dissociation scores than the non eating-disordered control group. Additionally, when considered separately, both the anorexic and bulimic groups had significantly higher dissociation scores than the control subjects. No significant difference was found in the level of dissociation between anorexic and bulimic groups. These findings are discussed in relation to previous investigations and implications for possible future research and treatment.

scholarly journals Conductivity Study of DTAB in Water and Ethanol-Water Mixture in the Presence and Absence of ZnSO4

2020 ◽  
Vol 17 (4) ◽  
pp. 1207
Author(s):  
Sangita Acharya ◽  
Tulasi Niraula ◽  
Ajaya Bhattarai
Keyword(s):  
Free Energy ◽  
Critical Micelle Concentration ◽  
Volume Fraction ◽  
Standard Free Energy ◽  
Water Mixture ◽  
Dodecyltrimethylammonium Bromide ◽  
Degree Of Dissociation ◽  
Ethanol Content ◽  
Presence And Absence ◽  
Free Energy Of Micellization

The physicochemical behaviour of dodecyltrimethylammonium bromide (DTAB) in water and ethanol-water mixture in the presence and absence of ZnSO4 were studied by measuring the conductivity at 298.15 K. The pre-micellar (S1) and post-micellar slopes (S2) were obtained and calculated the degree of dissociation (α) and the critical micelle concentration (cmc). With an increase in ethanol content, the cmc and α of DTAB increased whereas, in the presence of ZnSO4, the cmc and α decreased. By using cmc and α, thermodynamic properties as the standard free energy of micellization ( ) were evaluated. With an increase in ethanol content, the negative values of  are decreased indicating less spontaneous in the micellization which makes micellization less favourable. The correlation of the pre-micellar and post-micellar slopes with the volume fraction of ethanol were discussed. DTAB micellization was tested in contexts of specific solvent parameters and solvophobic parameter.

scholarly journals Predictive models for the phase behaviour and solution properties of weak electrolytes: nitric, sulphuric, and carbonic acids

2021 ◽  
Author(s):  
Maximilian Kohns ◽  
Georgia Lazarou ◽  
Spiros Kournopoulos ◽  
Esther Forte ◽  
Felipe A. Perdomo ◽  
...  
Keyword(s):  
Equilibrium Constants ◽  
Ion Pairing ◽  
Ionic Species ◽  
Phase Behaviour ◽  
Solution Properties ◽  
Science And Engineering ◽  
Degree Of Dissociation ◽  
Hydronium Ion ◽  
Weak Electrolytes ◽  
Carbonic Acids

The distribution of ionic species in electrolyte systems is important in many fields of science and engineering, ranging from the study of degradation mechanisms to the design of systems for electrochemical energy storage. Often, other phenomena closely related to ionic speciation, such as ion pairing, clustering and hydrogen bonding, which are difficult to investigate experimentally, are also of interest. Here, we develop an accurate molecular approach, accounting for reactions as well as association and ion pairing, to deliver a predictive framework that helps validate experiment and guides future modelling of speciation phenomena of weak electrolytes. We extend the SAFT-VRE Mie equation of state [D. K. Eriksen et al., Mol. Phys., 2016, 114, 2724–2749] to study aqueous solutions of nitric, sulphuric, and carbonic acids, considering complete and partially dissociated models. In order to incorporate the dissociation equilibria, correlations to experimental data for the relevant thermodynamic equilibrium constants of the dissociation reactions are taken from the literature and are imposed as a boundary condition in the calculations. The models for water, the hydronium ion, and carbon dioxide are treated as transferable and are taken from our previous work. We present new molecular models for nitric acid, and the nitrate, bisulfate, sulfate, and bicarbonate anions. The resulting framework is used to predict a range of phase behaviour and solution properties of the aqueous acids over wide ranges of concentration and temperature, including the degree of dissociation, as well as the activity coefficients of the ionic species, and the activity of water and osmotic coefficient, density, and vapour pressure of the solutions. The SAFT-VRE Mie models obtained in this manner provide a means of elucidating the mechanisms of association and ion pairing in the systems studied, complementing the experimental observations reported in the literature.

scholarly journals Сечения образования ионов He-=SUP=-+-=/SUP=- в различных электронных состояниях при столкновениях ионов He-=SUP=-2+-=/SUP=- с атомами водорода

2020 ◽  
Vol 90 (6) ◽  
pp. 895
Author(s):  
А.А. Басалаев ◽  
В.В. Кузьмичев ◽  
М.Н. Панов ◽  
О.В. Смирнов
Keyword(s):  
Kinetic Energy ◽  
Electron Capture ◽  
Cross Sections ◽  
Atomic Hydrogen ◽  
Precision Measurements ◽  
Capture Cross ◽  
Hydrogen Atoms ◽  
Hydrogen Target ◽  
Degree Of Dissociation ◽  
Capture Cross Sections

Using collision spectroscopy based on precision measurements of the kinetic energy of projectile ions that capture an electron, we measured the state selective electron capture cross sections of formation of He^+(n) ions at collision 3^He^{2 +} ions with an energy of E = 1.4-10 keV/a.m.u. with hydrogen atoms. The atomic hydrogen target with a degree of dissociation 78% at a temperature of tungsten dissociation cell 2180K has been made.

scholarly journals Impact of Solvation on the Structure and Reactivity of the Co3O4 (001)/H2O Interface: Insights From Molecular Dynamics Simulations

2020 ◽  
Vol 8 ◽  
Author(s):  
T. Kox ◽  
E. Spohr ◽  
S. Kenmoe
Keyword(s):  
Molecular Dynamics ◽  
Contact Layer ◽  
Ab Initio Molecular Dynamics ◽  
Water Dissociation ◽  
Degree Of Dissociation ◽  
Water Films ◽  
Dissociation Degree ◽  
In Operando ◽  
Dynamics Simulations ◽  
Potential Use

The spinel Co3O4 has many beneficial properties for potential use in catalysis. In operando, water is always present and alters the properties of the catalyst. We have used ab initio molecular dynamics to understand the effect of water and solvation on the structure and reactivity of the Co3O4 (001) A-type and B-type surface terminations. Water adsorbs on both terminations via a partial dissociative mode, and the A-termination is seen to be more reactive. On this surface, a higher degree of dissociation is observed in the topmost layers of the crystal in contact with water. Water dissociates more frequently on the Co2+ sites (about 75%) than on the adjacent Co3+ sites, where the degree of dissociation is about 50%. Increasing water coverage does not change the degree of water dissociation significantly. OH− adsorption on the Co2+ sites leads to a reduction of the amount of reconstruction and relaxation of the surface relative to the clean surface at room temperature. Proton transfer within the water films and between water molecules and surface has localized character. The B-terminated interface is less dynamic, and water forms epitactic layers on top of the Co3+ sites, with a dissociation degree of about 25% in the contact layer.

Über das Dissoziationsgleichgewicht realer Gase

1966 ◽  
Vol 21 (3) ◽  
pp. 252-255
Author(s):  
H. Koppe ◽  
G. Spies
Keyword(s):  
Cross Sections ◽  
Bound States ◽  
Exact Expression ◽  
Mass Action ◽  
Quantum Mechanical ◽  
Law Of Mass Action ◽  
Vibrational States ◽  
Degree Of Dissociation ◽  
Atom Scattering ◽  
Collision Approximation

The quantum mechanical cluster expansion, when applied to the partition function of a gas consisting of atoms whose bound states are the rotational and vibrational states of diatomic molecules, provides an exact expression for the degree of dissociation. The approximation containing only the second cluster integral is shown to be identical with the law of mass action involving the binary collision approximation for the activity coefficient of the dissociated constituent. This coefficient can be calculated from the phase shifts and thus from the cross sections of the elastic atom-atom-scattering.

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