Vol 4, No 19 (2016)
- Year: 2016
- Published: 14.12.2016
- Articles: 10
- URL: https://ogarev-online.ru/2311-2468/issue/view/23724
Full Issue
Determining of degree of substitution in hydroxyethyl methyl cellulose by solid-state 13C NMR spectroscopy
Abstract
The degree of substitution for methyl and hydroxyethyl substituents in hydroxyethyl methyl cellulose (GEMTS) was determined by solid-state 13C NMR spectroscopy. GEMTS six commercial samples of differing viscosity aqueous solutions were studied. The data on the degree of substitution were obtained by integrating various spectral ranges in 13C NMR spectrum considering the intensities of signals of different types of carbon atoms. The proposed method of measuring the degree of substitution is convenient and rapid. The experimental results agree well with the data on the degree of substitution stated by the manufacturer of the GEMTS samples studied.
Ogarev-online. 2016;4(19):2-9
2-9
Structural analysis of hydroxyethyl methyl cellulose by Fourier-transformed IR spectroscopy
Abstract
The chemical structure of mixed cellulose ethers containing methyl and hydroxyethyl groups was determined by FTIR spectroscopy. The content of various substituents was determined by the comparative analysis of the relative intensities of the absorption bands, symmetry index and crystallinity index for each hydroxyethyl methyl cellulose sample.
Ogarev-online. 2016;4(19):10-18
10-18
Effect of co-ions on iodide-selective electrode potential
Abstract
The effect of some inorganic and organic cations on the value of the potential and the electrochemical characteristics of the iodide selective electrode was investigated. The possible causes of distortion of the electrode function in the presence of Fe3+, Cu2+, papaverine, thiamine, drotaverine, diphenylhydramine are discussed.
Ogarev-online. 2016;4(19):19-25
19-25
Synthesis and sorption properties of nanosized magnesium phosphate in relation to copper (II) ions
Abstract
The nanosized sorbent based on magnesium phosphate was synthesized. The sorbent composition was studied by x-ray diffraction and IR-spectroscopic methods. The basic sorption characteristics of magnesium phosphate relative to copper (II) ions were defined.
Ogarev-online. 2016;4(19):26-31
26-31
Fluorimetric determination of silver (I) and zinc (II) as complexes with organic reagents
Abstract
Currently the derivatives of imidazole and acridine are widely studied because of their high selectivity and efficiency for the quantitative determination of elements in complexes. The study considers the application of new organic reagents for fluorimetric determination of silver and zink traces in various substances.
Ogarev-online. 2016;4(19):32-37
32-37
Synthesis of resveratrol analogue with trans-stilbazol skeleton
Abstract
The method for the synthesis of trans-stilbazol derivative - a synthetic analogue of natural phytoalexin resveratrol has been developed. The synthesized compound is a potential basis for the creation of new high efficient cytoprotectors with antioxidant action type.
Ogarev-online. 2016;4(19):38-42
38-42
Iron (II) clathrochelates as homogeneous electrocatalysts of hydrogen production at low pH
Abstract
Direct template macrobicyclization of three aliphatic, aromatic and dichlorinecontaining a-dioxime molecules with 4-pyridinylboronic acid on a Fe2+ ion as a matrix afforded the first macrobicyclic tris-dioximates with 4-pyridinyl apical substituents. Pyridinyl-functionilized iron (II) clathrochelates emerge as first homogeneous electrocatalysts of hydrogen evolution at low pH; varying their ribbed substituents allows designing electrocatalysts with better performance and stability in harsh near-industrial conditions.
Ogarev-online. 2016;4(19):43-46
43-46
Ionometric determination of cadmium (II) in the form of halide anion complexes
Abstract
The possibility of ionometric determination of Cd (II) in the form of halide anion complexes was shown. The main characteristics of the ion-selective electrode were studied. It is found that cations Al3 +, Ca2+, Cu2+, Zn2+ up to 50 fold excess do not prevent the determination. The relative standard deviation for the determination of cadmium (II) at 3,0 ∙ 10-4 mol / l in the presence of other ions is no more than 0,06.
Ogarev-online. 2016;4(19):47-52
47-52
53-58
Influence of concentration of magnesium salts on strength of cement stone filled with zeolite-containing rocks
Abstract
The paper presents a study of the interaction of magnesium salts and filled cement stone. The authors analyze the influence of the degree of filling with zeolite-containing rocks on the composite strength. The influence of magnesium salts concentration on the degree of destruction of filled cement samples has been determined.
Ogarev-online. 2016;4(19):59-66
59-66