Experimental and theoretical determination of vapor pressures of NaClKCl, NaBrKBr and NaClCaCl2 aqueous solutions at 298 to 343 K

1996 ◽  
Vol 124 (1-2) ◽  
pp. 235-249 ◽  
Author(s):  
I-Min Shiah ◽  
Hsieng-Cheng Tseng
Keyword(s):  
Aqueous Solutions ◽  
Vapor Pressures ◽  
Theoretical Determination

VAPOR PRESSURES OF AQUEOUS SOLUTIONS OF SILVER NITRATE, OF AMMONIUM NITRATE, AND OF LITHIUM NITRATE

1956 ◽  
Vol 34 (2) ◽  
pp. 151-159 ◽  
Author(s):  
A. N. Campbell ◽  
J. B. Fishman ◽  
G. Rutherford ◽  
T. P. Schaefer ◽  
L. Ross
Keyword(s):  
Aqueous Solutions ◽  
Silver Nitrate ◽  
Direct Determination ◽  
Lithium Ion ◽  
Silver Ions ◽  
Lithium Nitrate ◽  
Vapor Pressures ◽  
Heats Of Dilution ◽  
Water Of Hydration

This paper is devoted to the direct determination of the vapor pressures of solutions of the nitrates of silver, of ammonium, and of lithium, at temperatures varying from 30 °C. to 105 °C. and at concentrations varying from 10 to 85 weight % (for lithium nitrate, the limited solubility precluded measurements beyond 65%). From the vapor pressures, the enthalpies of evaporation of water (by a modification of the Clapeyron–Clausius equation), the differential heats of dilution, and the activities of water (as compared with the mole fractions of the solvent) have been calculated. From the results we conclude that the water of hydration of the ammonium and silver ions (if, indeed, these ions are hydrated at all) is very loosely attached, while that of the lithium ion is strongly bound.

Equilibrium Vapor Cell for Quantitative IR Absorbance Measurements

1996 ◽  
Vol 50 (10) ◽  
pp. 1307-1313 ◽  
Author(s):  
Paul E. Field ◽  
Roger J. Combs ◽  
Robert B. Knapp
Keyword(s):  
Aqueous Solutions ◽  
Gas Flow ◽  
Pure Component ◽  
Organic Solutes ◽  
Vapor Pressures ◽  
Water Solvent ◽  
Beer's Law ◽  
Solution Preparation ◽  
Beer’S Law

Infrared absorbance measurements through a gas flow cell are made with the closed-loop circulation of vapor/air mixtures equilibrated with the use of temperature-regulated aqueous solutions. Constant reproducible vapor pressures of organic solutes are established with the equilibrated aqueous solutions. The water solvent depresses the vapor pressure of the pure organic solutes of methanol, ethanol, isopropanol, acetone, and methyl ethyl ketone (MEK). Knowledge of the solution liquid mole fractions, the pure component vapor pressures, and the Wilson coefficients permits determination of the solute vapor pressures to within 2% accuracy. Reliable aqueous solution preparation requires only the correct weighings of pure constituent materials before mixing to achieve the targeted solute liquid mole fractions. Absorbances are measured for four of the five solutes over a range of seven concentrations and for MEK over four concentrations. These concentrations show the absorbance region of adherence to Beer's law with an experimental precision of approximately ±2% for the solutes studied. Absorptivities that are calculated from the Beer's law slope are compared to the available infrared absorbance data.

LUMINESCENT DETERMINATION OF SUGAR IN NATURAL HONEY

2020 ◽  
Vol 0 (4) ◽  
pp. 29-32
Author(s):  
B.M. GAREEV ◽  
◽  
A.M. ABDRAKHMANOV ◽  
G.L. SHARIPOV ◽  
◽  
...  
Keyword(s):  
Quantum Dots ◽  
Laboratory Test ◽  
Aqueous Solutions ◽  
Analytical Method ◽  
Sugar Content ◽  
Carbon Quantum Dots ◽  
Photoluminescence Intensity ◽  
Sucrose Content ◽  
Natural Honey

The photoluminescence of carbon quantum dots synthesized from natural honey and mixtures of honey and sugar has been studied. An increase in the sugar content leads to a decrease in the photoluminescence intensity without changing the shape of the luminescence spectrum of these quantum dots aqueous solutions, which is associated with a decrease in the yield of their synthesis in the sugar presence. The discovered effect can be used to detect sugar in honey. When examining five different market samples of flower honey using this method, two of them showed a significant decrease in the photoluminescence intensity. A laboratory test for compliance with GOST 19792-2017 Standard requirements established an excess of the sucrose content in these samples. Luminescent determination of sugar in honey does not require complicated equipment and can be used to develop a new analytical method for determining the sugar content in counterfeit natural honey.

Sorption of Lead by the Selective Ion Exchanger Ostsorb DETA

1992 ◽  
Vol 57 (7) ◽  
pp. 1393-1404 ◽  
Author(s):  
Ladislav Svoboda ◽  
Jan Uhlíř ◽  
Zdeněk Uhlíř
Keyword(s):  
Phosphoric Acid ◽  
Aqueous Solutions ◽  
Functional Groups ◽  
Ion Exchanger ◽  
Preconcentration Procedure ◽  
Bead Cellulose

The properties of Ostsorb DETA, a selective ion exchanger based on modified bead cellulose with chemically bonded diethylenetriamine functional groups, were studied, and its applicability to the preconcentration of trace amounts of lead from aqueous solutions was verified. The conditions of the preconcentration procedure in the column and batch modes were optimized for this purpose. The results obtained were applied to the determination of lead in phosphoric acid.

Vapor pressures of aqueous solutions of (silver, thallium, sodium) nitrate at 98.5.degree.C

1980 ◽  
Vol 25 (4) ◽  
pp. 331-332 ◽  
Author(s):  
Marie Christine Abraham ◽  
Maurice Abraham ◽  
James Sangster
Keyword(s):  
Aqueous Solutions ◽  
Sodium Nitrate ◽  
Vapor Pressures

Theoretical progress in the H2+ molecular ion: towards electron to proton mass ratio determinationThis paper was presented at the International Conference on Precision Physics of Simple Atomic Systems, held at École de Physique, les Houches, France, 30 May – 4 June, 2010.

2011 ◽  
Vol 89 (1) ◽  
pp. 103-107 ◽  
Author(s):  
J.-Ph. Karr ◽  
L. Hilico ◽  
V. I. Korobov
Keyword(s):  
High Resolution ◽  
Mass Ratio ◽  
Theoretical Determination ◽  
Atomic Systems ◽  
The Road ◽  
Theoretical Progress ◽  
Proton Mass ◽  
Accuracy Level ◽  
Ratio Determination

High resolution ro-vibrational spectroscopy of H 2+ or HD+ can lead to a significantly improved determination of the electron to proton mass ratio me/mp if the theoretical determination of transition frequencies becomes sufficiently accurate. We report on recent theoretical progress in the description of the hyperfine structure of H 2+ , as well as first steps in the evaluation of radiative corrections at order mα7. Completion of the latter calculation should allow us to reach the projected 10−10 accuracy level and open the road to mass ratio determination.

Combined Experimentaland Theoretical Determination of the Atomic Structure of the (310) Twin in NB

1991 ◽  
Vol 238 ◽  
Author(s):  
Geoffrey H. Campbells ◽  
Wayne E. King ◽  
Stephen M. Foiles ◽  
Peter Gumbsch ◽  
Manfred Rühle
Keyword(s):  
High Resolution ◽  
Theoretical Models ◽  
High Resolution Electron Microscopy ◽  
Interatomic Potentials ◽  
Image Simulation ◽  
Theoretical Determination ◽  
Atomic Structures ◽  
Resolution Electron ◽  
High Resolution Images

ABSTRACTA (310) twin boundary in Nb has been fabricated by diffusion bonding oriented single crystals and characterized using high resolution electron microscopy. Atomic structures for the boundary have been predicted using different interatomic potentials. Comparison of the theoretical models to the high resolution images has been performed through image simulation. On the basis of this comparison, one of the low energy structures predicted by theory can be ruled out.

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