Izvestiya of Saratov University.
ISSN 1816-9775 (Print)
ISSN 2541-8971 (Online)


Химия

Transformation of stable hydrogenate on catalytic systems Pt/CVM, Pr/CVM

Catalytic reforming is the most used method for upgrading straight-run gasolines. The trends to modernize catalytic systems so that the reforming process can be used in the industrial setting are focused on the production of catalysts with a specifi c set of characteristics allowing to obtain a liquid commercial product with the required operational and ecological features, in addition to increase its yield at lower temperatures. This article investigates the effi ciency of the catalytic systems Pt/CVM, Pr/CVM as transformation processes of raw hydrocarbons.

Eff ect of the MoO3/Al2O3 catalyst fl uorination on the propylene metathesis reaction

In the course of this work, fl uorinated catalysts MoO3 /Al2 O3 -F for the olefi ns metathesis have been synthesized. The materials have been characterized by various physicochemical methods and tested in the propylene metathesis reaction. It has been shown that the support fl uorination leads to partial replacement of surface hydroxyl groups by F, which is accompanied by an increase in the strength of both Lewis acid sites and residual bridging OH groups. Increasing the fl uorine content on γ-Al2O3 up to 3 wt.

Solid-phase sorbents based on synthetic nanofibers and glauconite for extracting magneson I from aqueous media

A comparative evaluation of the sorption capacity of synthetic and natural sorbents with respect to phenol and some of its derivatives has been carried out. Electrospun nanofi bers based on polyamide-6 (PA-6) were obtained under optimal conditions from a spinning solution of a polymer dissolved in a mixture of formic and acetic acids. The preparation of the clay mineral by the sieve method has been carried out, while the enriched fraction of glauconite (200–500 microns) has been isolated.

Determination of the content of iodine, iodides and iodates in food products

Currently iodine defi ciency diseases are one of the most important medical and social problems. In this regard, the purpose of the study is to determine the content of iodine, iodides, iodates in iodized salt, drinking and mineral water, seaweed, to determine the stability of the iodine content in salt. For the qualitative determination of iodides and iodates ions in salts and molecular iodine in seaweed, an iodine starch reaction has been carried out.

Determination of statins by reverse-phase HPLC in mobile phases with diff erent modifi cation options

The chromatographic behavior of atorvastatin, rosuvastatin and simvastatin in the presence of the main modifi ers of the mobile phase: elution strength and buff er solution, has been studied by means of the reverse-phase high-performance liquid chromatography (HPLC) method. Optimal modifi cation conditions have been found and their application for the determination of statins under study in the pharmaceutical preparations Atorvastatin-OBL, Liprimar and Tulip has been shown. The Sr value is 0.03. The relative determination error does not exceed 7%.

ИССЛЕДОВАНИЕ СВОЙСТВ ТВЕРДОГО ОСТАТКА ПИРОЛИЗА ОСАДКОВ СТОЧНЫХ ВОД

В статье показаны результаты исследования иловых осадков процесса очистки сточных вод. Проведен химический анализ иловых осадков отобраных из нескольких точек иловой площадки. Результат показывает, что значения рН колеблется в пределах 6,95-7,41, среда нейтральная, отсутствуют карбонат-ионы. По определению органического вещества в пробах из разных точек наблюдаются равномерные значения от 2,36% до 2,52%, что не характерны для других обнаруженных ионов: кальция, магния, калия, хлоридов и гидрокарбонатов.

ВЛИЯНИЕ ОРГАНИЧЕСКИХ И НЕОРГАНИЧЕСКИХ ВЕЩЕСТВ, СОДЕРЖАЩИХСЯ В ПИТЬЕВОЙ ВОДЕ, НА ЕЕ КАЧЕСТВО И ЗДОРОВЬЕ НАСЕЛЕНИЯ

Вода является одним из ключевых факторов здоровья человека. Качество питьевой воды – глобальная проблема современного человечества. Практически все ее источники подвергаются антропогенному и техногенному воздействию разной интенсивности. Проблема качества питьевой воды актуальна как в глобальном масштабе, так и в рамках отдельно взятого региона или населенного пункта.

Термогравиметрическое исследование содержания фракций воды в крови мышей в условиях острой гипоксии и гиперкапнии и под воздействием антигипрксантов

Гипоксия - широко распространенное явление, возникающее как в условиях дефицита кислорода во внешней среде, так и в результате различных патологий. При изменении внешних условий происходят изменения в соотношении структурных фракций воды и общего содержания воды. Структурное состояние воды зависит от стадии развития адаптационного синдрома. Степень гидратации биополимеров увеличивается на стадии резистентности организма и уменьшается на стадии истощения. Цель исследования - изучить фракции воды в крови под воздействием гипоксии и антигипоксантов.

Electrochemical SERS study of some endogenous components of human biofl uids

The work describes electrochemical (EC) protocol suitable for preparation of copper electrodes which can be used as substrates in surface-enhanced Raman spectroscopy (SERS). These SERS-active electrodes have been used for electrospectral studies based on the combination of electrochemical and SERS analysis (EC-SRS analysis). Several endogenous bodyfl uid components (urea, creatinine, uric acid, bilirubin) have been selected for the study because they can signifi cantly aff ect the SERS-based determination of other analytes in bodyfl uids (for example, drugs).

Phase tree, forecast of crystallizing phases and description of chemical interaction in the system KCl–CaCl2–BaCl2

The construction of a phases tree of a ternary system with three binary compounds KCaCl3 , K2 BaCl4 , CaBaCl4 is given. The phase tree includes four secondary phase triangles CaCl2 –KCaCl3 –СаBaCl4 , CaBaCl4 –KCaCl3 –BaCl2 , KCaCl3 –BaCl2 –K2 BaCl4 and KCaCl3 –CaBaCl4 –KCl. These triangles are connected by three stable secants KCaCl3 –СаBaCl4 , KCaCl3 –BaCl2 , KCaCl3 –K2 BaCl4 . Crystallizing phases in stable and secant elements correspond to the simplex tops.

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