7 results on '"Drozdov, Anatoliy L."'
Search Results
2. Silica-Containing Biomimetic Composites Based on Sea Urchin Skeleton and Polycalcium Organyl Silsesquioxane.
- Author
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Shapkin, Nikolay P., Khalchenko, Irina G., Drozdov, Anatoliy L., Fedorets, Aleksander N., Buravlev, Igor Yu, Andrasyuk, Anna A., Maslova, Natalya V., Pervakov, Kirill A., and Papynov, Evgeniy K.
- Subjects
CALCIUM silicates ,RAW materials ,COMPOSITE materials ,ARTIFICIAL neural networks ,CONVOLUTIONAL neural networks - Abstract
The paper presents an original approach to the synthesis of polycalciumorganyl silsesquioxanes through the reaction of polyorganyl silsesquioxanes [RSiO
1.5 ]n (where R is an ethyl and phenyl radical) with sea urchin skeleton under the conditions of mechanochemical activation. The novelty and practical significance of the present study lies in the use of an available natural raw source as a source of calcium ions to initiate the reaction of calcium silicate formation and create a matrix for the formation of a porous inorganic composite framework. The thermal stability of the introduced silicates, i.e., the ability to maintain a porous structure at high temperatures, is key to the production of an ordered porous material. The reaction scheme was proposed to be based on the interaction of calcium carbonate with the siloxane bond. FTIR, XRD, GPC, and TGA were used to study the composition and structure of the obtained materials. The cross-sectional area of the polymer chain and the volumes of the coherent scattering regions of the polymers obtained were calculated from the XRD data. To prepare the composites, the sea urchin skeleton was further modified with polycalciumorganyl silsesquioxanes in a toluene solution. To remove the sea urchin skeleton, the obtained biomimetic composites were treated with hydrochloric acid. The results of the morphological and surface composition studies are reported. The method proposed in the paper could be of fundamental importance for the possibility of obtaining structured porous composite materials for a wide range of practical applications, including for the purpose of creating a composite that may be a promising carrier for targeted delivery of chemotherapy agents. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
3. Synthesis of Porous Biomimetic Composites: A Sea Urchin Skeleton Used as a Template.
- Author
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Shapkin, Nikolay P., Papynov, Evgeniy K., Panasenko, Alexandr E., Khalchenko, Irina G., Mayorov, Vitaly Yu., Drozdov, Anatoliy L., Maslova, Natalya V., and Buravlev, Igor Yu.
- Subjects
SEA urchins ,BIOMIMETIC synthesis ,SILICON nitride ,SUSTAINABLE architecture ,SKELETON ,SCANNING electron microscopy ,PORE size distribution ,BIOMIMETIC materials - Abstract
The paper presents an original method for the template synthesis of biomimetic porous composites using polyferrophenylsiloxane (PFPS) and the skeleton of the sea urchin Strongylocentrotus intermedius as a structuring template. The study aimed to form an organosilicon base of a composite with an inverted structure relative to the original structure of the sea urchin shell with a period of structure movement of about 20 µm and ceramic composites fabrication with the silicate base with an average pore size distribution of about 10 μm obtained by the reaction of PFPS with the inorganic base of the sea urchin test under conditions of calcination at 1000 °C followed by acid etching. The composition and morphology of the obtained composites were investigated by IR, XRD, XPS, EDX, and SEM techniques and by mercury porosimetry; the parameters of the porous structures depend on the selected methods of their synthesis. The proposed method is of fundamental importance for developing methods for the chemical synthesis of new biomimetics with a unique porosity architecture based on environmentally friendly natural raw materials for a vast practical application. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
4. Silicon Compounds in Sponges.
- Author
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Drozdov, Anatoliy L., Zemnukhova, Lyudmila A., Panasenko, Alexandr E., Polyakova, Nataliya V., Slobodyuk, Arseniy B., Ustinov, Alexandr Yu., Didenko, Nina A., and Tyurin, Sergey A.
- Subjects
DEMOSPONGIAE ,SPONGES (Invertebrates) ,CALCIUM compounds ,ABSORPTION spectra ,FLUORESCENCE spectroscopy ,TRACE elements ,SILICON compounds - Abstract
A comparative study of the microscopic morphology and chemical characteristics of spicules of Hexactinellids (Hexactinellida) with different structural features of the skeletons, as well as the freshwater Baikal sponge belonging to the class of common sponges (Demospongia), was carried out. The trace element composition of sponge spicules was determined by X-ray fluorescence spectrometry. The spicules of siliceous sponges contain many elements, arranged in decreasing order of concentration: Si, Ca, Fe, Cl, K, Zn, and others. It was shown that the surface layer of sea sponges contains mainly carbon (C), oxygen (O), and to a lesser extent nitrogen (N), silicon (Si), and sodium (Na). The spicules of the studied siliceous sponges can be divided into two groups according to the phase composition, namely one containing crystalline calcium compounds and one without them. Analysis of infrared absorption spectra allows us to conclude that the sponges Euplectella aspergillum, E. suberia and Dactylocalyx sp. contain silica partially bound to the organic matrix, while the silica skeleton of the sponges of the other group (Schulzeviella gigas, Sericolophus sp., Asconema setubalense, Sarostegia oculata, Farrea sp. and Lubomirskia baicalensis sp.) practically does not differ from the precipitated SiO
2 . This comparative study of the chemical composition of the skeletons of marine Hexactinellids and common freshwater sponge allows us to conclude that there are no fundamental differences in the chemical composition of spicules, and all of them can be used as a starting material for creating new composite silicon–organic functional materials. [ABSTRACT FROM AUTHOR]- Published
- 2021
- Full Text
- View/download PDF
5. Principle of Conservatism of Cellular Structures as the Basis for Construction of the Multikingdom System of the Organic Word
- Author
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Drozdov, Anatoliy L.
- Subjects
Medical / Genetics - Abstract
This chapter describes the history of megasystematics (taxonomy of higher taxons) from Karl Linnaeus till the present day. Nowadays, the Whittaker’s five-kingdom system of cellular organisms is the best known. This system has made monophyletic the kingdoms of plants, fungi, and animals but increased the heterogeneity of the kingdom Protoctista. There is one of the qualitative peculiarities of the subcellular level of the organization of living systems, which has been named “the principle of conservatism.” We offer the multikingdom system of cellular organisms, based on this principle. In many ways, it can be done based on intuition. We promote the concept of three branches of cellular organisms that is accepted in megasystematics. It is proposed to give these branches of organic word the rank of domains Archaea, Bacteria, and Eucarya. The Empire Cellulata is divided into three domains, which, in turn, are divided into several kingdoms. Our system contains 26 kingdoms.
- Published
- 2017
6. On the reproduction of two deep-sea Arctic holothurians, Elpidia heckeri and Kolga hyalina (Holothuroidea:Elpidiidae).
- Author
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Kremenetskaia, Antonina, Ezhova, Olga, Drozdov, Anatoliy L., Rybakova, Elena, and Gebruk, Andrey
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SEA cucumbers ,REPRODUCTION ,GONADS ,ECHINODERMATA ,ICE - Abstract
Internal gonad morphology was examined in two species of elpidiid holothurians, Elpidia heckeri and Kolga hyalina, commonly occurring in the Central Arctic Ocean. The holothurians were sampled in August – September 2012 and in August 2018, at several locations in the Nansen and Amundsen Basins, in areas under the constant ice cover and in areas free of ice. Both species were observed at different reproductive stages and both are presumed to reproduce periodically. In 2012, spawning occurred at the beginning of September in Elpidia heckeri and from late August to early September in Kolga hyalina. There are reasons to believe that gametogenesis in K. hyalina depends on the availability of freshly deposited phytodetritus. The maximum oocyte size in Kolga hyalina (240 μm) was smaller than in Elpidia heckeri (390 μm). [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
7. Structural Arrangement and Properties of Spicules in Glass Sponges.
- Author
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Drozdov, Anatoliy L. and Karpenko, Alexander A.
- Subjects
- *
SPICULE (Anatomy) , *INVERTEBRATE anatomy , *GLASS , *AMORPHOUS substances , *SPONGES (Invertebrates) - Abstract
The morphology, chemical composition, and optical properties of long monoaxonic spicules were studied in several species of marine deep-sea hexactinellid sponges of different orders and families: Asconema setubalense (Hexasterophora, Lyssacinosida) and Monorhaphis chuni Schulze (Monorhaphiidae). Their macrostructural organization is a system of thin layers laid around the central cylinder containing a square canal filled with organic matter. A significant role in spicule organization is played by the organic matrix. The macrostructural of organization of the spicule in Monorhaphis chuni is a system of the "cylinder-within-a-cylinder" type. However the spicule surface is covered with ridges. They penetrate a few layers into the spicule. Analysis of the elemental composition of the basalia spicule of Monorhaphis chuni demonstrates a heterogeneous allocation of C, O, Si on the spicule surface, subsurface layers, and on ridges. All studied spicules have the properties of anisotropic crystals and they demonstrate a capability to the birefrigence. On the other hand we discovered unique property of spicules--their capacity for triboluminescence. The discovery of triboluminescence in composite organosilicon materials of which the spicules of hexactinellid sponges are built may contribute to the creation of biomimetic materials capable of generating light emission. [ABSTRACT FROM AUTHOR]
- Published
- 2011
- Full Text
- View/download PDF
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