The article presents the experience of the Institute of Archeology of the Russian Academy of Scie... more The article presents the experience of the Institute of Archeology of the Russian Academy of Science’s Markul Expedition, which utilized digital technologies for the study, preservation, and popularization of cultural heritage. The objective of the Markul Expedition was to obtain a complete picture of the historical and cultural landscape of Northwestern Colchis in antiquity by applying two key digital technologies: geographic information systems (GIS) and photogrammetry. The results obtained from the latter were used both independently and were integrated into GIS as separate layers (orthophotomaps, digital terrain models) or as hyperlinks to objects (3D models, videos, plans, sections, etc.). The objects investigated by the expedition are very diverse both in size and in terms of shooting conditions. Accordingly, each category of archaeological site required an individual approach, and a separate methodology and equipment. The final visualization angles differ to a fair extent fro...
The present study examined the references in the works of ancient authors to the ancient city and... more The present study examined the references in the works of ancient authors to the ancient city and the Roman fortress Pitiunt, the geological aspects of the formation of the coastline in the Pitsunda Cape area in the first centuries AD and the results of archaeological research of the monument performed from 1952 to 1974. The creation of the 3D reconstruction of the exterior of the Pitiunt fortress during its prosperity in the IV century AD, along with the churches which were the first monuments of religious architecture in northwestern Colchis (northwestern Colchis comprises parts of the territory of modern Russia, Georgia and Abkhazia) was carried out based on the excavation plans and the principles of fortification and temple architecture that were accepted in the late Roman times, paying special attention to the geological paleoreconstructions.
The study was devoted to the creation of transparent electrodes based on highly conductive mesh s... more The study was devoted to the creation of transparent electrodes based on highly conductive mesh structures. The analysis and reasonable choice of technological approaches to the production of such materials with a high Q factor (the ratio of transparency and electrical conductivity) were carried out. The developed manufacturing technology consists of the formation of grooves in a transparent substrate by photolithography methods, followed by reactive ion plasma etching and their metallization by chemical deposition using the silver mirror reaction. Experimental samples of a transparent electrode fabricated using this technology have a sheet resistance of about 0.1 Ω/sq with a light transmittance in the visible wavelength range of more than 60%.
Electron paramagnetic resonance ͑EPR͒ in iron-oxide nanoparticles ͑ϳ2.5 nm͒ embedded in a polyeth... more Electron paramagnetic resonance ͑EPR͒ in iron-oxide nanoparticles ͑ϳ2.5 nm͒ embedded in a polyethylene matrix reveals the sharp line broadening and the resonance field shift on sample cooling below T F Ϸ40 K. At the same temperature a distinct anomaly in the field-cooled magnetization is detected. The temperature dependences of EPR parameters below T F are definitely different than those found for various nanoparticles in the superparamagnetic regime. In contrast to canonical bulk spin glasses, a linear fall-off of the EPR linewidth is observed. Such behavior can be explained in terms of the random-field model of exchange anisotropy.
Our experimental results show that the technology created can be considered rather promising for ... more Our experimental results show that the technology created can be considered rather promising for the fabrication of advanced materials for magnetic and optical storage. In our opinion, available samples demonstrate the main properties required for these applications. At the same time, a study to create a commercial prototype of the magnetic storage media should be strongly correlated with activity in creating advanced read/write systems. It should be especially stressed that, as far as we know, the proposed technology is really the first available one that permits the fabrication of kilogramscale volumes of magnetic materials containing nanoparticles.
A method is proposed for the preparation of iron(III) oxide nanoparticles via thermal decompositi... more A method is proposed for the preparation of iron(III) oxide nanoparticles via thermal decomposition of iron(III) acetate in a high-temperature solution of polyethylene. The nanoparticles were characterized by EXAFS, EPR, and Mössbauer spectroscopy. The nearest neighbor environment of Fe in the nanoparticles was shown to be similar to that in the structure of γ-Fe 2 O 3 . According to the Mössbauer results, the material contains iron(III) oxide in superparamagnetic and ferromagnetic states similar to γ-Fe 2 O 3 . The particle size determined by high-resolution transmission electron microscopy is consistent with x-ray diffraction data. Experimental data are presented on the field-dependent magnetization of the material.
A method is described for preparing isolated Fe nanoparticles on the surface of poly(tetrafluoroe... more A method is described for preparing isolated Fe nanoparticles on the surface of poly(tetrafluoroethylene) (PTFE) nanogranules. The composition and atomic structure of the nanoparticles are investigated by transmission electron microscopy and EXAFS, x-ray emission, and Mössbauer spectroscopic techniques. The nanoparticles have a complex composition and structure and contain α -Fe (15%). The majority phase in the nanoparticles is iron carbide (48%). On the surface of the PTFE nanogranules, the nanoparticles react with fluorine, forming Fe-F bonds (12% FeF 2 ). The free surface of the nanoparticles, noninteracting with fluorine, is oxidized by oxygen to form Fe 2 O 3 (25%). A model for the structure of the nanoparticles is described.
This review considers advances in the fabrication of metallic, oxide, sulfide, carbon, BN, and ot... more This review considers advances in the fabrication of metallic, oxide, sulfide, carbon, BN, and other microgranules-the building blocks of porous materials for various applications. It is shown that attaching nanoparticles to the surface of microgranules alters some of the most important properties of the matrix and offers the possibility of creating composite materials with unique physical properties and reactivity. * O 2 , H 2 O 2 , or KMnO 4 . ** Different ratios.
We describe the first chlorine-free synthesis of nanozirconooligocarbosilanes through thermal coc... more We describe the first chlorine-free synthesis of nanozirconooligocarbosilanes through thermal cocondensation of low-molecular oligocarbosilanes and zirconium tetrakis(diethylamide). The starting reagents, reaction intermediates, and final products have been characterized by 1 H, 13 C, and 29 Si nuclear magnetic resonance, UV and IR spectroscopy, gel-permeation chromatography, thermogravimetry, transmission electron microscopy (TEM), and elemental analysis. The synthesized nanozirconooligocarbosilanes have been used to fabricate ceramic fibers and matrices through thermal and chemical processing. TEM results demonstrate that the particles of zirconium and products of its reactions with silicon, carbon, and nitrogen range in size from 10 to 20 nm in the oligomers and from 20 to 30 nm in the ceramics.
Bismuth nanoparticles have been produced in pores of opal matrices by reducing bismuth salts and ... more Bismuth nanoparticles have been produced in pores of opal matrices by reducing bismuth salts and oxide compounds with supercritical isopropanol. According to transmission electron microscopy data, the diameter of the SiO 2 spheres in the opal matrices is about 260 nm, and that of the bismuth nanoparticles does not exceed 80 nm.
We have prepared nanomaterials consisting of SiO 2 microgranules and Fe-containing nanoparticles ... more We have prepared nanomaterials consisting of SiO 2 microgranules and Fe-containing nanoparticles on their surface and determined the size and composition of the nanoparticles. The nanoparticles are shown to have a core-shell structure (α-Fe core and γ-Fe 2 O 3 shell). The α-Fe core and Fe 2 O 3 shell are responsible, respectively, for the broad and narrow lines in the EMR spectrum of the nanoparticles. The magnetic properties of larger nanoparticles are dominated by the core, while those of smaller nanoparticles are dominated by the oxide shell.
Polymer-matrix composites consisting of Fe 3 O 4 -Fe 2 O 3 and FeCoB nanoparticles in SKTN and SI... more Polymer-matrix composites consisting of Fe 3 O 4 -Fe 2 O 3 and FeCoB nanoparticles in SKTN and SIEL siloxane rubber matrices are synthesized. The introduction of nanoparticles into siloxane oligomers leads to their polymerization, resulting in polymer-matrix nanomaterials. Transmission electron microscopy and small-angle x-ray scattering are used to determine the size of the Fe-containing nanoparticles. The magnetic properties of the nanocomposites are studied by electron magnetic resonance.
Cobalt-containing nanoparticles have been prepared via thermal decomposition of cobalt acetate on... more Cobalt-containing nanoparticles have been prepared via thermal decomposition of cobalt acetate on the surface of poly(tetrafluoroethylene) (PTFE) microgranules forming a fluidized bed over the surface of hot mineral oil. Using transmission electron microscopy, the average size of the cobalt-containing nanoparticles has been determined to be 3.6 nm. The composition and structure of the nanoparticles have been determined by x-ray diffraction, extended x-ray absorption fine structure spectroscopy, and electron paramagnetic resonance, and the magnetic properties of the synthesized nanomaterial have been studied. The results indicate that the nanoparticles have a core-shell structure, with a metallic cobalt core (Ӎ 10 vol %) and a shell consisting of three phases: ëÓ 3 é 4 (Ӎ 80%) and small amounts of CoO and CoF 2 (Ӎ 10%). The fluoride phase results from the interaction of the nanoparticles with surface fluorine atoms of the PTFE microgranules.
Nanocomposites of cadmium sulfide and high-pressure polyethylene have been synthesized. The mecha... more Nanocomposites of cadmium sulfide and high-pressure polyethylene have been synthesized. The mechanism of the thermal decomposition of thiourea complexes during the synthesis of cadmium sulfide nanoparticles has been investigated. The nanoparticle size, composition, and structure of the nanocomposites have been determined by x-ray diffraction, transmission electron microscopy, IR spectroscopy, and EXAFS spectroscopy, and the thermal decomposition of the nanomaterials has been studied.
We have prepared nanocomposites consisting of narrowly sized metal-containing nanoparticles embed... more We have prepared nanocomposites consisting of narrowly sized metal-containing nanoparticles embedded in a polyethylene matrix and have established conditions for the fabrication of thick films and bulk materials from the synthesized polymer powders. Dielectric permittivity and resistivity measurements demonstrate that the electrical properties of the nanocomposites depend significantly on the nanoparticle size and content. The microwave absorption and permittivity of the materials are shown to vary little in a broad frequency range. The magnetization (including the remanent one) of the cobalt-containing nanomaterials is higher than that of the iron-containing samples.
The synthesis of CdS nanoparticles stabilized in the bulk of a polyethylene matrix is described. ... more The synthesis of CdS nanoparticles stabilized in the bulk of a polyethylene matrix is described. The size of synthesized nanoparticles is determined by means of transmission electron microscopy. The composition of nanoparticles is defined by X-ray phase analysis. It is shown that the variation of the process-dependent parameters during synthesis of nanoparticles in a polymer + oil solution melt results in the formation of CdS nanoparticles with average sizes of 4.9, 5.4, and 6.2 nm with a reasonably narrow size distribution and wellformed structure. The optical properties of synthesized nanomaterials are investigated. The investigation of Raman scattering reveals softening of the LO-phonon mode with decreasing CdS nanoparticle size. A broad high-energy band of photoluminescence connected with the exciton annihilation in conditions of size quantization is detected.
The composition and molecular structure of preceramic nanozirconooligocarbosilanes have been dete... more The composition and molecular structure of preceramic nanozirconooligocarbosilanes have been determined using a variety of physicochemical characterization techniques: nuclear magnetic resonance (1 H, 29 Si, 13 C), IR spectroscopy, transmission electron microscopy, gel permeation chromatography, scanning electron microscopy, thermogravimetry, X ray photoelectron spectroscopy, and elemental analysis.
Nanosized copper-containing particles stabilized on the surface of polymer nanograins were obtain... more Nanosized copper-containing particles stabilized on the surface of polymer nanograins were obtained by thermal decomposition of copper-containing precursors in a fluidized bed of ultradispersed polytetrafluoroethylene. Transmission electron microscopy showed that the average size of nanoparticles is 10 − 12 nm. The structure of the particles was determined by EXAFS, EPR, and X-ray powder diffraction. The copper nanoparticles consist of a core and a shell and are well structured. The core is copper metal, whereas the surface layer, which constitutes no more than 2% of the nanoparticle weight, is copper oxide.
The article presents the experience of the Institute of Archeology of the Russian Academy of Scie... more The article presents the experience of the Institute of Archeology of the Russian Academy of Science’s Markul Expedition, which utilized digital technologies for the study, preservation, and popularization of cultural heritage. The objective of the Markul Expedition was to obtain a complete picture of the historical and cultural landscape of Northwestern Colchis in antiquity by applying two key digital technologies: geographic information systems (GIS) and photogrammetry. The results obtained from the latter were used both independently and were integrated into GIS as separate layers (orthophotomaps, digital terrain models) or as hyperlinks to objects (3D models, videos, plans, sections, etc.). The objects investigated by the expedition are very diverse both in size and in terms of shooting conditions. Accordingly, each category of archaeological site required an individual approach, and a separate methodology and equipment. The final visualization angles differ to a fair extent fro...
The present study examined the references in the works of ancient authors to the ancient city and... more The present study examined the references in the works of ancient authors to the ancient city and the Roman fortress Pitiunt, the geological aspects of the formation of the coastline in the Pitsunda Cape area in the first centuries AD and the results of archaeological research of the monument performed from 1952 to 1974. The creation of the 3D reconstruction of the exterior of the Pitiunt fortress during its prosperity in the IV century AD, along with the churches which were the first monuments of religious architecture in northwestern Colchis (northwestern Colchis comprises parts of the territory of modern Russia, Georgia and Abkhazia) was carried out based on the excavation plans and the principles of fortification and temple architecture that were accepted in the late Roman times, paying special attention to the geological paleoreconstructions.
The study was devoted to the creation of transparent electrodes based on highly conductive mesh s... more The study was devoted to the creation of transparent electrodes based on highly conductive mesh structures. The analysis and reasonable choice of technological approaches to the production of such materials with a high Q factor (the ratio of transparency and electrical conductivity) were carried out. The developed manufacturing technology consists of the formation of grooves in a transparent substrate by photolithography methods, followed by reactive ion plasma etching and their metallization by chemical deposition using the silver mirror reaction. Experimental samples of a transparent electrode fabricated using this technology have a sheet resistance of about 0.1 Ω/sq with a light transmittance in the visible wavelength range of more than 60%.
Electron paramagnetic resonance ͑EPR͒ in iron-oxide nanoparticles ͑ϳ2.5 nm͒ embedded in a polyeth... more Electron paramagnetic resonance ͑EPR͒ in iron-oxide nanoparticles ͑ϳ2.5 nm͒ embedded in a polyethylene matrix reveals the sharp line broadening and the resonance field shift on sample cooling below T F Ϸ40 K. At the same temperature a distinct anomaly in the field-cooled magnetization is detected. The temperature dependences of EPR parameters below T F are definitely different than those found for various nanoparticles in the superparamagnetic regime. In contrast to canonical bulk spin glasses, a linear fall-off of the EPR linewidth is observed. Such behavior can be explained in terms of the random-field model of exchange anisotropy.
Our experimental results show that the technology created can be considered rather promising for ... more Our experimental results show that the technology created can be considered rather promising for the fabrication of advanced materials for magnetic and optical storage. In our opinion, available samples demonstrate the main properties required for these applications. At the same time, a study to create a commercial prototype of the magnetic storage media should be strongly correlated with activity in creating advanced read/write systems. It should be especially stressed that, as far as we know, the proposed technology is really the first available one that permits the fabrication of kilogramscale volumes of magnetic materials containing nanoparticles.
A method is proposed for the preparation of iron(III) oxide nanoparticles via thermal decompositi... more A method is proposed for the preparation of iron(III) oxide nanoparticles via thermal decomposition of iron(III) acetate in a high-temperature solution of polyethylene. The nanoparticles were characterized by EXAFS, EPR, and Mössbauer spectroscopy. The nearest neighbor environment of Fe in the nanoparticles was shown to be similar to that in the structure of γ-Fe 2 O 3 . According to the Mössbauer results, the material contains iron(III) oxide in superparamagnetic and ferromagnetic states similar to γ-Fe 2 O 3 . The particle size determined by high-resolution transmission electron microscopy is consistent with x-ray diffraction data. Experimental data are presented on the field-dependent magnetization of the material.
A method is described for preparing isolated Fe nanoparticles on the surface of poly(tetrafluoroe... more A method is described for preparing isolated Fe nanoparticles on the surface of poly(tetrafluoroethylene) (PTFE) nanogranules. The composition and atomic structure of the nanoparticles are investigated by transmission electron microscopy and EXAFS, x-ray emission, and Mössbauer spectroscopic techniques. The nanoparticles have a complex composition and structure and contain α -Fe (15%). The majority phase in the nanoparticles is iron carbide (48%). On the surface of the PTFE nanogranules, the nanoparticles react with fluorine, forming Fe-F bonds (12% FeF 2 ). The free surface of the nanoparticles, noninteracting with fluorine, is oxidized by oxygen to form Fe 2 O 3 (25%). A model for the structure of the nanoparticles is described.
This review considers advances in the fabrication of metallic, oxide, sulfide, carbon, BN, and ot... more This review considers advances in the fabrication of metallic, oxide, sulfide, carbon, BN, and other microgranules-the building blocks of porous materials for various applications. It is shown that attaching nanoparticles to the surface of microgranules alters some of the most important properties of the matrix and offers the possibility of creating composite materials with unique physical properties and reactivity. * O 2 , H 2 O 2 , or KMnO 4 . ** Different ratios.
We describe the first chlorine-free synthesis of nanozirconooligocarbosilanes through thermal coc... more We describe the first chlorine-free synthesis of nanozirconooligocarbosilanes through thermal cocondensation of low-molecular oligocarbosilanes and zirconium tetrakis(diethylamide). The starting reagents, reaction intermediates, and final products have been characterized by 1 H, 13 C, and 29 Si nuclear magnetic resonance, UV and IR spectroscopy, gel-permeation chromatography, thermogravimetry, transmission electron microscopy (TEM), and elemental analysis. The synthesized nanozirconooligocarbosilanes have been used to fabricate ceramic fibers and matrices through thermal and chemical processing. TEM results demonstrate that the particles of zirconium and products of its reactions with silicon, carbon, and nitrogen range in size from 10 to 20 nm in the oligomers and from 20 to 30 nm in the ceramics.
Bismuth nanoparticles have been produced in pores of opal matrices by reducing bismuth salts and ... more Bismuth nanoparticles have been produced in pores of opal matrices by reducing bismuth salts and oxide compounds with supercritical isopropanol. According to transmission electron microscopy data, the diameter of the SiO 2 spheres in the opal matrices is about 260 nm, and that of the bismuth nanoparticles does not exceed 80 nm.
We have prepared nanomaterials consisting of SiO 2 microgranules and Fe-containing nanoparticles ... more We have prepared nanomaterials consisting of SiO 2 microgranules and Fe-containing nanoparticles on their surface and determined the size and composition of the nanoparticles. The nanoparticles are shown to have a core-shell structure (α-Fe core and γ-Fe 2 O 3 shell). The α-Fe core and Fe 2 O 3 shell are responsible, respectively, for the broad and narrow lines in the EMR spectrum of the nanoparticles. The magnetic properties of larger nanoparticles are dominated by the core, while those of smaller nanoparticles are dominated by the oxide shell.
Polymer-matrix composites consisting of Fe 3 O 4 -Fe 2 O 3 and FeCoB nanoparticles in SKTN and SI... more Polymer-matrix composites consisting of Fe 3 O 4 -Fe 2 O 3 and FeCoB nanoparticles in SKTN and SIEL siloxane rubber matrices are synthesized. The introduction of nanoparticles into siloxane oligomers leads to their polymerization, resulting in polymer-matrix nanomaterials. Transmission electron microscopy and small-angle x-ray scattering are used to determine the size of the Fe-containing nanoparticles. The magnetic properties of the nanocomposites are studied by electron magnetic resonance.
Cobalt-containing nanoparticles have been prepared via thermal decomposition of cobalt acetate on... more Cobalt-containing nanoparticles have been prepared via thermal decomposition of cobalt acetate on the surface of poly(tetrafluoroethylene) (PTFE) microgranules forming a fluidized bed over the surface of hot mineral oil. Using transmission electron microscopy, the average size of the cobalt-containing nanoparticles has been determined to be 3.6 nm. The composition and structure of the nanoparticles have been determined by x-ray diffraction, extended x-ray absorption fine structure spectroscopy, and electron paramagnetic resonance, and the magnetic properties of the synthesized nanomaterial have been studied. The results indicate that the nanoparticles have a core-shell structure, with a metallic cobalt core (Ӎ 10 vol %) and a shell consisting of three phases: ëÓ 3 é 4 (Ӎ 80%) and small amounts of CoO and CoF 2 (Ӎ 10%). The fluoride phase results from the interaction of the nanoparticles with surface fluorine atoms of the PTFE microgranules.
Nanocomposites of cadmium sulfide and high-pressure polyethylene have been synthesized. The mecha... more Nanocomposites of cadmium sulfide and high-pressure polyethylene have been synthesized. The mechanism of the thermal decomposition of thiourea complexes during the synthesis of cadmium sulfide nanoparticles has been investigated. The nanoparticle size, composition, and structure of the nanocomposites have been determined by x-ray diffraction, transmission electron microscopy, IR spectroscopy, and EXAFS spectroscopy, and the thermal decomposition of the nanomaterials has been studied.
We have prepared nanocomposites consisting of narrowly sized metal-containing nanoparticles embed... more We have prepared nanocomposites consisting of narrowly sized metal-containing nanoparticles embedded in a polyethylene matrix and have established conditions for the fabrication of thick films and bulk materials from the synthesized polymer powders. Dielectric permittivity and resistivity measurements demonstrate that the electrical properties of the nanocomposites depend significantly on the nanoparticle size and content. The microwave absorption and permittivity of the materials are shown to vary little in a broad frequency range. The magnetization (including the remanent one) of the cobalt-containing nanomaterials is higher than that of the iron-containing samples.
The synthesis of CdS nanoparticles stabilized in the bulk of a polyethylene matrix is described. ... more The synthesis of CdS nanoparticles stabilized in the bulk of a polyethylene matrix is described. The size of synthesized nanoparticles is determined by means of transmission electron microscopy. The composition of nanoparticles is defined by X-ray phase analysis. It is shown that the variation of the process-dependent parameters during synthesis of nanoparticles in a polymer + oil solution melt results in the formation of CdS nanoparticles with average sizes of 4.9, 5.4, and 6.2 nm with a reasonably narrow size distribution and wellformed structure. The optical properties of synthesized nanomaterials are investigated. The investigation of Raman scattering reveals softening of the LO-phonon mode with decreasing CdS nanoparticle size. A broad high-energy band of photoluminescence connected with the exciton annihilation in conditions of size quantization is detected.
The composition and molecular structure of preceramic nanozirconooligocarbosilanes have been dete... more The composition and molecular structure of preceramic nanozirconooligocarbosilanes have been determined using a variety of physicochemical characterization techniques: nuclear magnetic resonance (1 H, 29 Si, 13 C), IR spectroscopy, transmission electron microscopy, gel permeation chromatography, scanning electron microscopy, thermogravimetry, X ray photoelectron spectroscopy, and elemental analysis.
Nanosized copper-containing particles stabilized on the surface of polymer nanograins were obtain... more Nanosized copper-containing particles stabilized on the surface of polymer nanograins were obtained by thermal decomposition of copper-containing precursors in a fluidized bed of ultradispersed polytetrafluoroethylene. Transmission electron microscopy showed that the average size of nanoparticles is 10 − 12 nm. The structure of the particles was determined by EXAFS, EPR, and X-ray powder diffraction. The copper nanoparticles consist of a core and a shell and are well structured. The core is copper metal, whereas the surface layer, which constitutes no more than 2% of the nanoparticle weight, is copper oxide.
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