Properties of KSCN-rich Molten NaSCN-KSCN Mixtures

1991 ◽  
Vol 46 (6) ◽  
pp. 540-544
Author(s):  
Yasuhiko Iwadata ◽  
Junichi Mochinaga ◽  
Kazuo Igarashi ◽  
Koji Tajiri ◽  
Tadashi Asahina ◽  
...  
Keyword(s):  
Electrical Conductivity ◽  
Surface Tension ◽  
Heat Capacity ◽  
Refractive Index ◽  
Molar Volume ◽  
Molten State

AbstractFor molten (Na, K)SCN mixtures with more than 50 mol% KSCN the molar volume Vm,electrical conductivity, χ, refractive index n, surface tension γ and heat capacity CP were measured in dependence of composition and temperature, γ exhibited the minimum at ca. 70 mol% KSCN and Cp was 148 JK-1 mol-1 in the range of 413 to 471 K. The electronic polarizabilities of the ions in the molten state were estimated by the semiclassical Clausius-Mossotti equation

scholarly journals Comparative Analysis of the Physicochemical Parameters of Breast Milk, Starter Infant Formulas and Commercial Cow Milks in Serbia

2016 ◽  
Vol 33 (2) ◽  
pp. 101-108 ◽  
Author(s):  
Slavica Sunarić ◽  
Tatjana Jovanović ◽  
Ana Spasić ◽  
Marko Denić ◽  
Gordana Kocić
Keyword(s):  
Electrical Conductivity ◽  
Surface Tension ◽  
Refractive Index ◽  
Breast Milk ◽  
Human Milk ◽  
Physicochemical Parameters ◽  
Titratable Acidity ◽  
Cow Milk ◽  
Physical Parameters ◽  
Infant Formulas

Summary Data on the physical properties of cow milk and infant formulas are important since they indicate the differences in physicochemical and rheological characteristics and compatibility with natural breast milk. This fact is important not only for quality control but also for the use of these commercial products as infant diet supplements or as complete breast milk substitutes. This study was undertaken to determine refractive index, surface tension, pH, electrical conductivity, viscosity and titratable acidity of the UHT cow milk, starter infant formulas and breast milk of Serbian mothers in order to compare commercial milk formulations with natural human milk. The paper also presents the measured data of some physical parameters of human milk about which there is little information in the literature. It has been also demonstrated how these parameters were changed by freezing and prolonged storage of breast milk. In this study, 8 commercial cow milks, 6 starter infant formulas and 15 different samples of colostrum, transition and mature breast milk were included. The titratable acidity, pH, electrical conductivity, refractive index, viscosity and surface tension were measured by using standardized techniques. It has been found that infant formulas available on the Serbian market differ in physicochemical parameters compared to breast milk. Regarding these parameters, none of the analyzed formulas fully corresponded to breast milk. It has been also shown that measurement of physical parameters is simple and inexpensive way to monitor the milk shelf-life which is important for human milk banks.

Physical and Rheological Properties of Poly-floral Honey from the Iraqi Kurdistan Region and the Effect of Temperature on its Viscosity

2020 ◽  
Vol 16 ◽  
Author(s):  
Auday Khudaier Azawy ◽  
Kocher Jamal Ibrahim ◽  
Omed Gh. Abdullah ◽  
Beshroo Abdulkareem Othman ◽  
Jasim M. S. Al-Saadi
Keyword(s):  
Electrical Conductivity ◽  
Surface Tension ◽  
Heat Capacity ◽  
Moisture Content ◽  
Rheological Properties ◽  
Ash Content ◽  
Soluble Solids ◽  
Effect Of Temperature ◽  
Free Acidity ◽  
Kurdistan Region

Aims: In this study, the physical and rheological properties of three poly-floral honey samples collected from different places in the Kurdistan region were determined. Methods: The honey samples were analyzed for pH, free acidity, total ash content, moisture content, refractive index, soluble solids (Brix), electrical conductivity, volume expansion, density, specific heat capacity, surface tension, and rheological properties. The pH and free acidity of the honey samples varied from 4.10 to 4.81 to 30 to 62 mEq/kg, respectively. The total ash content ranged from 0.166 to 0.408 %. The moisture content, soluble solids, and refractive index ranged from 15.60 to 16.60 g/100 g, 83.40 to 84.40, and 1.4998 to 1.5023, respectively. The electrical conductivity ranged from 40.896 to 44.471 mS/cm. The linear relationship between the electrical conductivity and the ash content was also calculated in this investigation. The volumetric expansion coefficient of the honey samples varied from 6.0098x10-4 to 6.69942x10-4 mm3 /K. The density ranged from 1.42125995 to 1.45501137 g/cm3 . The specific heat capacity of the varied from 2448.078 to 2575.004 J/kg.K. The surface tension varied from 0.2178 to 0.2282 N/m. The apparent viscosity was measured by Brookfield Viscometer, and the dynamic viscosity was measured by HAAKE Falling Ball Viscometer, after changing the temperature from 293 to 323 K. Results and Discussion: The honey samples of lower moisture content showed a greater increase in their apparent and dynamic viscosities. Arrhenius model was used to describe the effect of temperature on the honey viscosity. This model was used to determine the activation energy. Other rheological properties as kinematic viscosity and fluidity, were also determined. Conclusion: All the honey samples behaved as Newtonian fluids in the whole temperature range.

Model for calculating physicochemical properties of aluminosilicate melt

2013 ◽  
Vol 32 (2) ◽  
pp. 139-147
Author(s):  
Guo-Hua Zhang ◽  
Kuo-Chih Chou
Keyword(s):  
Electrical Conductivity ◽  
Surface Tension ◽  
High Temperature ◽  
Physicochemical Properties ◽  
Molar Volume ◽  
Experimental Measurement ◽  
Slag System ◽  
Difficult Issue ◽  
Do So

AbstractIt is an important issue to calculate the physicochemical properties of aluminosilicate melt based on some known data. However, it is also a difficult issue to do so, especially for a multicomponent slag system since the available data are very limited due to the difficulty of experimental measurement at high temperature. In this paper, a method is suggested to resolve this problem, which is particularly significant. This model can be well used to estimate the electrical conductivity, viscosity, molar volume and surface tension of aluminosilicate melt.

scholarly journals Influence of Small Quantities of Water on the Physical Properties of Alkylammonium Nitrate Ionic Liquids

2021 ◽  
Vol 22 (14) ◽  
pp. 7334
Author(s):  
David Ausín ◽  
Juan J. Parajó ◽  
José L. Trenzado ◽  
Luis M. Varela ◽  
Oscar Cabeza ◽  
...  
Keyword(s):  
Electrical Conductivity ◽  
Surface Tension ◽  
Refractive Index ◽  
Ionic Liquids ◽  
Physical Properties ◽  
Transport Processes ◽  
Average Percentage ◽  
Wide Range ◽  
Ethylammonium Nitrate ◽  
Potential Applications

This paper presents a comprehensive study of two alkylammonium nitrate ionic liquids. As part of this family of materials, mainly ethylammonium nitrate (EAN) and also propylammonium nitrate (PAN) have attracted a great deal of attention during the last decades due to their potential applications in many fields. Although there have been numerous publications focused on the measurement of their physical properties, a great dispersion can be observed in the results obtained for the same magnitude. One of the critical points to be taken into account in their physical characterization is their water content. Thus, the main objective of this work was to determine the degree of influence of the presence of small quantities of water in EAN and PAN on the measurement of density, viscosity, electrical conductivity, refractive index and surface tension. For this purpose, the first three properties were determined in samples of EAN and PAN with water contents below 30,000 ppm in a wide range of temperatures, between 5 and 95 °C, while the last two were obtained at 25 °C. As a result of this study, it has been concluded that the presence of water is critical in those physical properties that involve mass or charge transport processes, resulting in the finding that the absolute value of the average percentage change in both viscosity and electrical conductivity is above 40%. Meanwhile, refractive index (≤0.3%), density (≤0.5%) and surface tension (≤2%) present much less significant changes.

scholarly journals Behavior and properties of water in silicate melts under deep mantle conditions

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Bijaya B. Karki ◽  
Dipta B. Ghosh ◽  
Shun-ichiro Karato
Keyword(s):  
Electrical Conductivity ◽  
Molar Volume ◽  
Water Solution ◽  
Pure Water ◽  
Electrical Conductance ◽  
Water Structure ◽  
Bulk Water ◽  
Silicate Melts ◽  
Pressure Regime ◽  
Low Pressures

AbstractWater (H2O) as one of the most abundant fluids present in Earth plays crucial role in the generation and transport of magmas in the interior. Though hydrous silicate melts have been studied extensively, the experimental data are confined to relatively low pressures and the computational results are still rare. Moreover, these studies imply large differences in the way water influences the physical properties of silicate magmas, such as density and electrical conductivity. Here, we investigate the equation of state, speciation, and transport properties of water dissolved in Mg1−xFexSiO3 and Mg2(1−x)Fe2xSiO4 melts (for x = 0 and 0.25) as well as in its bulk (pure) fluid state over the entire mantle pressure regime at 2000–4000 K using first-principles molecular dynamics. The simulation results allow us to constrain the partial molar volume of the water component in melts along with the molar volume of pure water. The predicted volume of silicate melt + water solution is negative at low pressures and becomes almost zero above 15 GPa. Consequently, the hydrous component tends to lower the melt density to similar extent over much of the mantle pressure regime irrespective of composition. Our results also show that hydrogen diffuses fast in silicate melts and enhances the melt electrical conductivity in a way that differs from electrical conduction in the bulk water. The speciation of the water component varies considerably from the bulk water structure as well. Water is dissolved in melts mostly as hydroxyls at low pressure and as –O–H–O–, –O–H–O–H– and other extended species with increasing pressure. On the other hand, the pure water behaves as a molecular fluid below 15 GPa, gradually becoming a dissociated fluid with further compression. On the basis of modeled density and conductivity results, we suggest that partial melts containing a few percent of water may be gravitationally trapped both above and below the upper mantle-transition region. Moreover, such hydrous melts can give rise to detectable electrical conductance by means of electromagnetic sounding observations.

scholarly journals Quality Assessment of Raw Honey Issued from Eastern Romania

Agriculture ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 247
Author(s):  
Aida Albu ◽  
Cristina-Gabriela Radu-Rusu ◽  
Ioan Mircea Pop ◽  
Gabriela Frunza ◽  
Gherasim Nacu
Keyword(s):  
Electrical Conductivity ◽  
Refractive Index ◽  
Storage Conditions ◽  
Quality Parameters ◽  
Climatic Conditions ◽  
Ash Content ◽  
Botanical Origin ◽  
Free Acidity ◽  
Qualitative Level ◽  
Raw Honey

Romania is known among the main European honey producers, due to the variety of landforms as well as the diversity of the flora. Thirty-four honey samples of the acacia, linden and multifloral types, produced in eastern Romania and collected during 2013–2018, were physico-chemically analyzed using methods provided by the national and EU standards. The results of water-insoluble solids, color and refractive index were found to be 0.023–0.131%, 0.3–76.4 mm Pfund and 1.485–1.499, respectively. The moisture content ranged between 15.20% and 20.77%, solid substances content ranged between 79.23% and 84.80% and total soluble substances content ranged between 77.83 °Brix and 83.26 °Brix. The obtained values of specific gravity were from 1.414 to 1.450 g/cm3, pH ranged from 3.673 to 5.503 and free acidity ranged between 2.4 meq and 50 meq kg−1. The ash content and the electrical conductivity varied between 0.030 and 0.543% and 130 and 679 µS cm−1, respectively. Pearsonʹs correlation analysis showed an intense association of the ash content with electrical conductivity (r = 0.81). Our findings reveal the qualitative level of Romanian honey and the variation in quality parameters due to factors such as geographical region, climatic conditions, botanical origin and handling or storage conditions.

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