Creating a composite material ZnO-Bi2O3 with a core-shell structure for varistor ceramics

This paper discusses use of the plasma dynamic synthesis to obtain ZnO-Bi₂O₃composite powder. This method allows to get the main ZnO material with the formation of coreshell particles. Sintering of ceramics from this material was carried out using spark plasmasintering facility. Use of this sintering method provides obtaining a fine-grained structure of ZnO(average grain size of 1.3 μm). Comparison of the current-voltage characteristics of ceramicsfrom commercial and plasma dynamic materials showed promise of using a ZnO- Bi₂O₃composite with a core-shell structure

Influence study of the plasma dynamic method energy parameters on the phase composition of the Al-Mg-O system products

This article shows the possibility of obtaining aluminum-magnesium-oxygen system materials by plasma dynamic synthesis. The results of the influence study of the coaxial magnetoplasma accelerator input energy on the phase composition of the plasma dynamic synthesis product are presented. X-ray structural analysis showed the possibility of obtaining nanostructured material with the content of the phases of gamma aluminum oxide and some spinels of different stoichiometry. It was found that with increasing the value of the accelerator input energy, the total percentage of the spinel phases decreases from 12 to 7%. The results of transmission electron microscopy confirmed the absence of the spinel phase MgAl2O4 in the product of plasma dynamic synthesis obtained at a higher value of the input energy

Phase composition reproportioning of the plasma dynamic synthesis product of the zinc-bismuth-oxygen system

This article shows the possibility of obtaining nanosized materials based on zinc oxide and bismuth oxide by plasma dynamic synthesis. The main research in the article is the results on the influence of the precursors mass on the products phase composition of the Zn-Bi-O system. X-ray phase analysis allowed to establish the possibility of zinc oxide and bismuth oxide synthesis in one short cycle of the coaxial magnetoplasma accelerator. Changing the metal bismuth batch weight allows to adjust the bismuth oxide content in the final product. Transmission electron microscopy confirms the presence of zinc oxide phases in the bismuth oxide shell in the obtained material. Evaluation of the bismuth oxide shell thickness by determining the average size of the coherent scattering region showed that it is 30 nm

The last reconnection of the Marmara Sea (Turkey) to the World Ocean : A paleoceanographic and paleoclimatic perspective

Author Posting. © Elsevier B.V., 2008. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Marine Geology 255 (2008): 64-82, doi:10.1016/j.margeo.2008.07.005.During the late glacial, marine isotope Stage 2, the Marmara Sea transformed into a brackish lake as global sea level fell below the sill in the Dardanelles Strait. A record of the basin’s reconnection to the global ocean is preserved in its sediments permitting the extraction of the paleoceanographic and paleoclimatic history of the region. The goal of this study is to develop a high-resolution record of the lacustrine to marine transition of Marmara Sea in order to reconstruct regional and global climatic events at 24 a millennial scale. For this purpose, we mapped the paleoshorelines of Marmara Sea along the northern, eastern, and southern shelves at Çekmece, Prince Islands, and Imrali, using data from multibeam bathymetry, high-resolution subbottom profiling (chirp) and ten sediment cores. Detailed sedimentologic, biostratigraphic (foraminifers, mollusk, diatoms), X-ray fluorescence geochemical scanning, and oxygen and carbon stable isotope analyses correlated to a calibrated radiocarbon chronology provided evidence for cold and dry conditions prior to 15 ka BP, warm conditions of the Bolling-Allerod from ~15 to 13 ka BP, a rapid marine incursion at 12 ka BP, still stand of Marmara Sea and sediment reworking of the paleoshorelines during the Younger Dryas at ~11.5 to 10.5 ka BP, and development of strong stratification and influx of nutrients as Black Sea waters spilled into Marmara Sea at 9.2 ka BP. Stable environmental conditions developed in Marmara Sea after 6.0 ka BP as sea-level reached its present shoreline and the basin floors filled with sediments achieving their present configuration.Support for the analyses was from NSF-OCE-0222139; OCE-9807266 and PSC-CUNY 69138-00 38

Sound Effect "Glitch Machine"

This thesis addresses software music effects and their implementation. It shows design and implementation of the Glitch Machine, which belongs to the music multieffect programs and demonstrates the simultaneous use of various music effects to process audio signals. The result is a program for Windows OS, which utilizes cooperation of various effects, namely a filter, reverb, distortion, extractor, reverz, stutter, shifter, pitch resample and gain. It allows extensive and detailed editing of an audio track and a higher extent of manipulation with sounds, than with single music effects. Other components of the program include visualisations of the waveform and frequency spectrum of audio signals and an option for loading and saving effect presets. The program was tested in tests of the performance and memory usage and also with user testing of quality and graphical interface

Dostopriměčatel'nyja putešestvīja i otkrytīja XVIII věka

izd. G. CimmermanIn kyrill. Schr