Chemistry

Investigation of the Structure and Ways of Formation of Isomeric Tyenylsubstituted Triazolohexohydroquinazolines by Methods of NMR Spectroscopy and Chromato-mass-spectromectry

In the three-component condensation of thiophenecarbaldehyde, cyclohexanone and 3-amino-1,2,4-triazole triazolohexahydroquinazolines are formed, which are isomeric in the type of the ring junction and the double bond position in them, the structure of which is established by 1H NMR spectra. With the GC-EIMS-analysis of the composition of the reaction mass at various temperatures, it has been established that an intermediate in the formation of final products is azomethine (instead of a possible α,β-unsaturated ketone).

Synthesis and Structure Mixedligand Complexes of Fe, Co and Ni with Dimerkaptophenols and Heterocyclic Diamines

Physico-chemical methods investigated complexing Fe (II, III), Co (II) and Ni (II) with di mer kap tophenols (2,6-dimerkaptophenol, 2,6-dimercapto- 4-methylphenol, 2,6-dimercapto-4-ethy l phenol, 2,6-dimercapto-4-propylphenol and 2,6-dimercapto-4-tert-butylphenol), and hyd rophobic amines. The hydrophobic amine were used as heterocyclic diamine- 1,10-phenan thro line, 2,2’-bipyridyl and 4,7-diphenyl-1,10-phenanthroline (batofenantrolin). The optimal conditions for the formation and extraction mixedligand complexes and set the ratio of the components in the complexes.

Modelling of Drying Process of Natural Gas at a Pressure of 20–25 MPa through Aluminogel and NaA 4A Zeolite

Containment of water vapor in natural gas prevents its transportation and applying as an internal combustion fuel. The most demanded drying technology is adsorption at high pressure. The construction of a mathematical model for predicting the process is a significant task. Through a mathematical model of the process of water adsorption from natural gas at pressures of 20–25 MPa and temperatures of 5–40°C in the presence of NaA 4A zeolite and aluminogel, commonly used dehumidifier, optimal drying conditions were selected.

Phase Diagrams of the Ternary Systems Potassium Carbonate + Water + Hydrocarbon at 25°С

The phase diagrams of the ternary systems potassium carbo- nate+water+hydrocarbon (toluene, n.dodecane) at 25°С were first studied by means of the methods of sections and isothermal titration. The phase diagrams of both systems belong to those of ternary systems with salting-out of the binary heterogeneous system. Potassium carbon- ate sesquihydrate is the solid phase of monotectic equilibrium. Nine tie lines were drawn on the delamination field of the phase diagram of each ternary system.

The Experimental Study of Solubility of Helium in Propan-2-ol at Temperatures 360, 420 and 480 К

The experimental study of solubility of helium in propan-2-ol at high pressures and temperatures was performed. The following values of Henry’s law constants for the solution of helium in propan-2-ol were obtained: 168,7 ± 6,3 MPa at 480 К, 341,2 ± 13,6 MPa at 420 К and 602,0 ± 43,5 MPa at 360 К.

Structure of Hydroperoxide Anion from the Viewpoint of Quantum Chemistry

In living nature, of significance is lipid peroxidation caused by highly- reactive oxygen-containing species. Hydroperoxide anion –OOH represents a protolytic kind of hydrogen peroxide H2O2 – one of active forms of oxygen, – and a precursor of hydroperoxyradical •OOH – another one. The work is aimed at the investigation of spa- tial and electronic structure of hydroperoxide anion.

Preconcentration of Е110 and Е124 Food Azodyes on Magnetite Nanoparticles Modified by CTAB

Synthetic azodyes are widely used in paint, textile, plastic, and food, beverage, and leather, cosmetic, pharmaceutical and paper industries to make products more visually attractive to consumers. Therefore, they are also the components of waste waters and should be removed due to their potential risk to human health. Many techniques have been employed to eliminate dyes from waste water and do to preconcen- tration before analysis in food or beverage objects. One of the most popular and effective is magnetic solid-phase extraction (MSPE) with the use of magnetic nanoparticles (MNP).

Effect of Surface Plasmon Resonance in the Fluorometric Properties of Molecules and Complexes

The optical properties of noble metal nanoparticles feature the pres- ence of a pronounced resonance band in the visible light spectrum, called the surface plasmon resonance band. The influence of local surface plasmons on the dynamics of singlet–triplet energy transfer in the donor–acceptor pair is the subject of recent active studies by analysts in connection with the prospective using of nanoparticles in optosensorics and the opportunity of significant improvements of the metrological characteristics of analytical techniques.

Solid-state Potentiometric Sensors for the Determination of Cefuroxime Axetil in Aqueous Media and Oral Fluid

Cefuroxime axetil is a cephalosporin antibiotic of the second generation, it is used in the sequential therapy of patient with sinusitis, community-acquired pneumonia, and other infectious somatic pathologies. For the determination of cephalosporin antibiotics in different objects, spectroscopic, chromatographic, electrochemical methods, immunoassay, etc. are used, which demand for expen- sive devices and organic solvents. Potentiometric sensors let one expressively detect cefalosporin antibiotics in small samples without previous sample preparation.

Increase of Activity Industrial Catalys for Isomerisation Normal Hydrocarbons

Was done the studie of activity zeolite-containing catalyst Cr2О3 +Bi2О3 /ZSM-5 and technical catalyst SI-2, also they combained action in process of conversion of n-hexane at lay-by-layers download. In the process of conversion n-hexane on Cr2О3 +Bi2О3 /ZSM-5 catalyst prevails reaction of cracking and destroy of n-hexane to two symmetric molecule of propane (51,4%). Lay-by-layers download of Cr2О3 +Bi2О3 /ZSM-5 and SI-2 catalysts with high conversion nhexane to achieve a lot of contents iso-hydrocarbons in products of conversion with 200 oC.

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