Preparation of a chelating sorbent based on pyridylethylated polyethylenimine for recovering transition metal ions

A method was developed for preparing a chelating amino polymer, pyridylethylpolyethylenimine with maximal degree of substitution, by polymer-analogous transformations of branched polyethylenimine in reaction with 2-vinylpyridine. The ability of cross-linked pyridylethylpolyethylenimine with the degree of substitution of 0.32 to sorb Cu2+, Ni2+, Co2+, Zn2+, Cd2+, Mn2+, and Pb 2+ ions present simultaneously in solution was evaluated. In an ammonium acetate sorption system (pH 3.5-4.0), the sorbent selectively interacts with Cu(II) ions. © 2013 Pleiades Publishing, Ltd

ІЗОТЕРМІЧНИЙ ПЕРЕРІЗ ДІАГРАМИ СТАНУ СИСТЕМИ Al2O3−TiO2−Nd2O3 ПРИ 1400 °С

Isothermal section of the Al2O3–TiO2–Nd2O3 phase diagram at 1400 °C is constructed for the first time. It is the part of systematic investigations of Al2O3–TiO2–Ln2O3 (Ln=lanthanides,Y) systems. The 1400°C was taken as the temperature, at which no liquid is expected in the system. Samples were prepared by a chemical method. Samples were annealed in air at 1400°С for 80 hours and cooled in the furnace. Phases in the samples were determined by XRD analysis. New phases and appreciable homogeneity regions based on components and binary compounds were not found. Isothermal section consists of seven narrow twophase and eight three-phase regions. Triangulation of the system is determined by the phase Nd2Ti2O7, which is in equilibrium with compounds Al2TiO5, NdAlO3 and system components TiO2 and Al2O3. Formation of phases Nd4Ti9O24, Nd2Ti3O12 and Nd2TiO5 in binary boundary system TiO2–Nd2O3 causes the appearance of partially quasibinary sections Al2TiO5–Nd4Ti9O24, Al2TiO5–Nd2Ti3O12 and NdAlO3–Nd2TiO5. The obtained results make a significant contribution to the understanding of interactions between the components in the system studied. The system includes binary compounds with high electro-optical, ferroelectric, piezoelectric, photocatalytic properties, mikrowave dielectric ceramic. In addition, in the system we expects the existence of new three-phase and two-phase eutectics, which can be obtained in the form of high-temperature structural materials by the directional solidification. This fact opens up the possibility to fi nd and establish the coordinates of new three-phase and two-phase eutectics for directional solidifi cation and to obtain new high-temperature structural materials in the Al2O3–TiO2–Nd2O3 system

Адсорбция TX-100 и SDBS на поверхности нанопорошков Al2O3 и γ-Fe2O3 из водных растворов

Adsorption equilibriums in aqueous aluminum and iron oxides nanosuspensions stabilized by SDBS and TX-100 were investigated using UV spectrophotometry. It was established that the non-ionic surfactant TritonX-100 is not adsorbed from aqueous solution on a hydrophilic surface of both aluminum and iron oxide nanoparticles. At the same time adsorption of the anionic surfactant SDBS was observed in both oxides nanoparticles. In the investigated range of concentrations adsorption isotherms SDBS from aqueous solution on the surfaces of nanoparticles Al2O3 and γ-Fe2O3 not reach saturation. The share of the particles surface occupied by surfactant molecules were estimated based on the value of an area of molecules SDBS in the adsorption layer, which was derived from the isotherm of surface tension (0.10 nm2). The calculations showed that at the investigated concentrations SDBS Al2O3 employed approximately 30 % of surface of nanoparticles, and for γ-Fe2O3 – up to 10%.Методом УФ-спектрофотомерии были исследованы адсорбционные равновесия в водных наносуспензиях оксидов алюминия и железа, стабилизированных SDBS и TX-100. Установлено, что неионогенный ПАВ TritonX-100 не адсорбируется из водного раствора на гидрофильной поверхности наночастиц оксидов, как алюминия, так и железа. В то же время, для анионного ПАВ SDBS адсорбция наблюдалась на наночастицах обоих оксидов

SORPTION-SPECTROSCOPIC DETERMINATION OF CADMIUM (II) IONS

The range of pH values in which the sorption of cadmium ions on KB-4 cationite proceeds most fully both in the presence of 4-(2-pyridylazo)resorcinol and without it has been determined. The possibility of developing a test method for determining the content of cadmium in solutions has been assessed

Carbon Paper Modified with Functionalized Poly(diallyldimethylammonium chloride) Graphene and Gold Phytonanoparticles as a Promising Sensing Material: Characterization and Electroanalysis of Ponceau 4R in Food Samples

This paper presents a novel eco-friendly sensing material based on carbon paper (CP) volumetrically modified with a composite nanomodifier that includes functionalized poly(diallyldimethylammonium chloride) graphene (PDDA-G) and phytosynthesized gold nanoparticles (phyto-AuNPs). The functionalization of graphene was justified by Fourier-transform infrared spectroscopy. The phyto-AuNPs (d = 6 nm) were prepared by “green” synthesis with the use of strawberry leaf extract. The sensing material was characterized using scanning electron microscopy, electrochemical impedance spectroscopy, and voltammetry. The research results indicated a more than double increase in the electroactive surface area; a decrease in the resistance of electron transfer on nanocomposite-modified CP, compared to bare CP. The phyto-AuNPs/PDDA-G/CP was used for the electrosensing of the synthetic dye Ponceau 4R. The oxidation signal of colorant enhanced 4-fold on phyto-AuNPs/PDDA-G/CP in comparison to CP. The effect of the quantity of nanomodifier, solution pH, potential scan rate, accumulation parameters, and differential pulse parameters on the peak current of Ponceau 4R was studied. Under optimal conditions, excellent sensory characteristics were established: LOD 0.6 nM and LR 0.001–2 μM for Ponceau 4R. High selectivity and sensitivity enable the use of the sensor for analyzing the content of Ponceau 4R in food products (soft drinks, candies, and popsicles) without additional sample preparation. © 2022 by the authors

Experience in managing patients with Churg-Strauss syndrome.

Our goal was to analyze the possibilities of impro­ving the diagnostics of CSS and to improve the effectiveness of treatment according to the existing literature and our own experience of long-term care for patients with eosinophilic granulomatosis with polyangiitis or Churg-Strauss syndrome (CSS). The medical histories of three female patients aged 26 to 46-years and a 20-year-old male patient were considered. The duration of the disease before the established diagnosis was 5-17 years. Anamnesis and medical documents analysis showed a typical CSS debut in the form of allergic rhinitis, nasal polyps, which were recurrent after polypectomy, and respiratory disorders, which were regarded as bronchitis or bronchial asthma – corresponding to the first phase, also called the prodromal or allergic stage of CSS. The prodromal period lasts up to 10 years or more and is characterized by various allergic manifestations, more often –  pollinosis or bronchial asthma, that is difficult to control. But CSS can be suspected because of low effectiveness of the therapy with inhaled steroids, lack of effect of antibiotics and eosinophilia more than 10% that occurs periodically. Even in the third stage of CSS in systemic manifestations of vasculitis and severe secondary lesions of organs and tissues with functional impairment, constant intake of maintenance doses of corticosteroids and cytostatics allows to achieve stabilization of the process in patients with CSS

Diagnosis and treatment of diffuse toxic goiter and autoimmune thyroiditis combination

С целью определения выраженности тиреотоксикоза и назначения адекватной терапии целесообразно определение как уровня гормонов щитовидной железы, так и антител к рецепторам ТТГ и назначать иммуномодуляторы после исследования иммунологического статуса больного

Experience in the use of transcatheter sympathetic denervation of the renal arteries of treatment-resistant hypertension

Цель: Изучение эффективности и безопасности использования транскатетерной симпатической денервации почечных артерий (ТКСДПА) в лечении резистентной артериальной гипертензии (АГ). Методы исследования: измерение офисного АД, суточное мониторирование АД (СМАД), определение скорости клубочковой фильтрации (СКФ), ТКСДПА

Effects of Impurity Content on the Sintering Characteristics of Plasma-Sprayed Zirconia

Yttria-stabilized zirconia powders, containing different levels of SiO2 and Al2O3, have been plasma sprayed onto metallic substrates. The coatings were detached from their substrates and a dilatometer was used to monitor the dimensional changes they exhibited during prolonged heat treatments. It was found that specimens containing higher levels of silica and alumina exhibited higher rates of linear contraction, in both in-plane and through-thickness directions. The in-plane stiffness and the through-thickness thermal conductivity were also measured after different heat treatments and these were found to increase at a greater rate for specimens with higher impurity (silica and alumina) levels. Changes in the pore architecture during heat treatments were studied using Mercury Intrusion Porosimetry (MIP). Fine scale porosity (<_50 nm) was found to be sharply reduced even by relatively short heat treatments. This is correlated with improvements in inter-splat bonding and partial healing of intra-splat microcracks, which are responsible for the observed changes in stiffness and conductivity, as well as the dimensional changes