Transformation Of Experimental Data Research Articles

CONSTANTS OF ELECTROLYTIC DISSOCIATION OF THE LITHIUM, SODIUM AND POTASSIUM SULFATES IN AQUEOUS ISOPROPANOL SOLUTIONS

At introduction of isopropyl alcohol in saturated aqueous solutions of sulfates of lithium, sodium and potassium at 25 °C physico-chemical properties of the studied systems Li2SO4-H2O-C3H7OH, Na2SO4-H2O-C3H7OH and K2SO4-H2O-C3H7OH are changed. This reduces the density of solutions and salt content in aqueous isopropanol solutions due to a decrease in solubility of salts. It is shown that the variation of the volume content of alcohol from 0% to 90% results in the decrease of Li2SO4 solubility 1280 times, Na2SO4 – 548 times, K2SO4 – in 278 times. Alcohol additives also affect the degree of electrolytic dissociation of salt in aqueous isopropanol solutions. To study the electrochemical properties of salts we used conductometric method based on the measurement of the molar conductivity of solutions depending on salt concentration. In aqueous solutions, alkali metal sulfates exhibit the properties of strong electrolytes and almost completely dissociate into ions. When the volume content of isopropanol in the solution is more than 30%, alkali metal sulfates begin to show the properties of weak electrolytes, as evidenced by the correlation of the molar conductivity of the diluted solution with the salt concentration under the equation describing the state of weak electrolytes. From the transformations of experimental data in the coordinates of this equation, the values of the electrolytic dissociation constants of the studied salts were determined, which vary (8.30 ± 0.01)·10-5 to (4,35 ± 0,01)·10-8 (mol/l)2 when varying the alcohol content from 30 to 90% volume. It is shown that isopropanol additives reduce the constant (and hence the degree) of electrolytic dissociation of alkali metal sulfates: the higher the alcohol concentration in the solution, the weaker the salt becomes as an electrolyte. The value of the electrolytic dissociation constant depends on the nature of the salt: with an increase in the size of the sulfate cation, the electrolytic dissociation constant decreases.

Effect of the preliminary transformation of experimental data on the accuracy of results of processing X-ray reflectograms

An effect of the preliminary transformation of experimental data of relative two-wave X-ray reflectometry on the accuracy of determining parameters of multilayer structures is described. The efficiency of applying the CUDA technology to the computer processing of results is investigated. An efficient implementation of calculations in modeling the relative two-wave X-ray reflectometry using CUDA is proposed.

Direct conversion of rheological compliance measurements into storage and loss moduli

We remove the need for Laplace/inverse-Laplace transformations of experimental data, by presenting a direct and straightforward mathematical procedure for obtaining frequency-dependent storage and loss moduli [G'(omega) and G''(omega), respectively], from time-dependent experimental measurements. The procedure is applicable to ordinary rheological creep (stress-step) measurements, as well as all microrheological techniques, whether they access a Brownian mean-square displacement, or a forced compliance. Data can be substituted directly into our simple formula, thus eliminating traditional fitting and smoothing procedures that disguise relevant experimental noise.

Functional transformation of experimental data and the chemical model of equilibrium for polynuclear systems-1. Family of auxiliary concentration functions curves with common cross-over point

The differential relationships between concentration variables and some of the auxiliary concentration functions for systems with complex formation reactions have been obtained. Systems which give a family of concentration functions with a common cross-over point are discussed in detail. The derived equations were shown to be useful in the determination of the chemical model of equilibrium as well as for evaluating the accuracy of available data. The proposed approach was applied for the determination of composition and stability of complexes in some real systems.

Application of Standard Differential Operators to Generation of Dynamic Systems Monitoring Algorithms Using Distributed Intellectual Tools

Abstract The techniques of Standard Differential Identification (Lototsky and others, 1986) are developed to solve several problems of dynamic systems inspection and monitoring. These techniques are based on special nonlinear differential transformations of experimental data and checking if the transformed input-output dependencies have a simple linear form. The example of wear detection algorithm is given. The concepts of hardware and software implementation of proposed algorithms are discussed.

Dose‐Response Relationships in Prenatal Toxicity*

Abstract Data and considerations on the significance of establishing dose‐response relationships in embryotoxicity (and especially teratogenicity) are presented here.The problems discussed include the following topics:‐ analysis and transformation of experimental data;‐ dose‐response curves for various embryotoxic effects;‐ reproducibility of studies on prenatal toxicity;‐ prenatal versus maternal toxicity;‐ quantitative risk assessment;‐ “threshold” for teratogenic effects;‐ analyses of combinations of teratogens;‐ relationship between molecular events and chemical teratogenicity.