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Volume 7, Nº 2 (2017)

Article

Chain reactions of gas combustion, explosion, and detonation: Chemical methods for process management

Azatyan V.

Resumo

It has been shown that gas-phase combustion processes, in contrast to the formed opinion, proceed via a branched-chain mechanism not only under extremely low pressure without temperature change but also at atmospheric pressure and increased pressures in any temperature mode. The features of ignition, flame propagation, explosion, and detonation of gases have been explained on the basis of the theory of nonisothermal chain reactions and experimentally confirmed for pressure and temperature regions important for technology. Chemical methods for the management of these combustion modes have been developed.

Reviews and Advances in Chemistry. 2017;7(2):125-146
pages 125-146 views

Determination of proteins in blood. Part 2: Determination of globulins

Buzanovskii V.

Resumo

The review presents the chronological development of procedures for determining the concentrations of total protein and albumin; total concentration of globulins; concentrations of subfractions, classes, and subclasses of globulins; and total concentrations of globulin subclasses in human blood. A brief overview of these procedures and the results of their comparative tests in medical examination of patients are given. The considered procedures are systematized; their advantages and disadvantages are discussed. It is noted that procedures for measuring the concentration of total protein, albumin, and globulin classes in plasma, serum, and whole blood are widely used in modern clinical diagnostic laboratories when performing routine assays. The concentrations of globulin subclasses and total concentrations of globulin subclasses in blood are mainly determined in biomedical research. Procedures for measuring the concentration of total globulins and globulin subfractions in plasma and serum are of historical importance and now are barely applied in clinical and diagnostic laboratories.

Reviews and Advances in Chemistry. 2017;7(2):147-221
pages 147-221 views

Electrostatic forces and geometry of organic molecules. Part II. Unsaturated acyclic molecules with one double bond: C=C, C=O, or C=N

Kirpichenok M., Titarenko Z., Vasilevich N., Ofitserov E., Zefirov N.

Resumo

In the extension of the electrostatic approach developed in the previous paper on the basis of the available experimental and ab initio calculations data, the geometric structure of acyclic organic molecules containing one isolated chemical bond C=C, C=O, or C=N was analyzed. In agreement with conventional σ/π-representation for this type of bonds, the electrostatic model was suggested, comprising two kinds of local electron densities (LEDs) differing in topology and polarizability, which are in the close spin–spin interaction and show some asymmetry in behavior under the action of external perturbing electrostatic forces (ESFs). Based on the previously introduced concepts of LEDs, point positive charges (PPCs), directions of their most effective interaction (MEI) and using the procedure of fixed molecule (FM), the capabilities of the model were demonstrated on the examples of typical alkenes, carbonyl compounds, azomethines and oximes.

Reviews and Advances in Chemistry. 2017;7(2):222-259
pages 222-259 views