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<article article-type="research-article" dtd-version="1.3" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xml:lang="ru"><front><journal-meta><journal-id journal-id-type="publisher-id">radioelectronics</journal-id><journal-title-group><journal-title xml:lang="ru">Известия высших учебных заведений России. Радиоэлектроника</journal-title><trans-title-group xml:lang="en"><trans-title>Journal of the Russian Universities. Radioelectronics</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">1993-8985</issn><issn pub-type="epub">2658-4794</issn><publisher><publisher-name>Saint Petersburg Electrotechnical University</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.32603/1993-8985-2019-22-5-93-106</article-id><article-id custom-type="elpub" pub-id-type="custom">radioelectronics-379</article-id><article-categories><subj-group subj-group-type="heading"><subject>Research Article</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="ru"><subject>КВАНТОВАЯ, ТВЕРДОТЕЛЬНАЯ, ПЛАЗМЕННАЯ И ВАКУУМНАЯ ЭЛЕКТРОНИКА</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>QUANTUM, SOLID-STATE, PLASMA AND VACUUM ELECTRONICS</subject></subj-group></article-categories><title-group><article-title>From Gas Sensors to Detection of Etanol Vapour to Sensor of Bacteria Detection</article-title><trans-title-group xml:lang="en"><trans-title>From Gas Sensors to Detection of Etanol Vapour to Sensor of Bacteria Detection</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-5451-1189</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Dimitrov</surname><given-names>Dimitre Tz.</given-names></name><name name-style="western" xml:lang="en"><surname>Dimitrov</surname><given-names>Dimitre Tz.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Dimitre Tz. Dimitrov, PhD (Eng.) (1998), Associate Professor of the Department of Inorganic Chemistry at the Sofia University St. Kliment Ohridski, Bulgaria and head of the Laboratory of Nanoparticle Science and Technology there. He is the author of 53 scientific publications. Area of expertise: photocatalysis; sensors and biosensors.</p><p>15 Tsar Osvoboditel Blvd., Sofia 1504, Bulgaria</p></bio><bio xml:lang="en"><p>Dimitre Tz. Dimitrov, PhD (Eng.) (1998), Associate Professor of the Department of Inorganic Chemistry at the Sofia University St. Kliment Ohridski, Bulgaria and head of the Laboratory of Nanoparticle Science and Technology there. He is the author of 53 scientific publications. Area of expertise: photocatalysis; sensors and biosensors.</p><p>15 Tsar Osvoboditel Blvd., Sofia 1504, Bulgaria</p></bio><email xlink:type="simple">dimitrov2001@yahoo.com</email><xref ref-type="aff" rid="aff-1"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>Sofia University St. Kliment Ohridski</institution><country>Болгария</country></aff><aff xml:lang="en"><institution>Sofia University St. Kliment Ohridski</institution><country>Bulgaria</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2019</year></pub-date><pub-date pub-type="epub"><day>04</day><month>12</month><year>2019</year></pub-date><volume>22</volume><issue>5</issue><fpage>93</fpage><lpage>106</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Dimitrov D.T., 2019</copyright-statement><copyright-year>2019</copyright-year><copyright-holder xml:lang="ru">Dimitrov D.T.</copyright-holder><copyright-holder xml:lang="en">Dimitrov D.T.</copyright-holder><license xml:lang="ru" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>Данная работа распространяется под лицензией Creative Commons Attribution 4.0.</license-p></license><license xml:lang="en" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>This work is licensed under a Creative Commons Attribution 4.0 License.</license-p></license></permissions><self-uri xlink:href="https://re.eltech.ru/jour/article/view/379">https://re.eltech.ru/jour/article/view/379</self-uri><abstract><sec><title>Introduction</title><p>Introduction. Metal oxide semiconductor sensors have many advantages. But their working temperature is still high and their sensitivities are frequently low. In the current work, I present the results from investigation of sensing ability of new kind of potentiometric solid state gas sensor.</p></sec><sec><title>Aim</title><p>Aim. The main goal of this work is investigation of the temperature dependence in the flow of air and in ethanol vapour mixture of the investigated junction structures. Also, we investigated at fixed temperature the dependence of the thermoelectric force from the ethanol vapour concentration at possible low operation temperature. For the structure, which shows the lowest operation temperature to ethanol vapour, we investigate the ability to detect Pseudomonas putida suspension.</p></sec><sec><title>Materials and methods</title><p>Materials and methods. In this work, the sensitivity to ethanol vapour and Pseudomonas putida suspension were investigated by measuring the thermoelectric force (the voltage) appearing of the structures by standart voltmeters.</p></sec><sec><title>Results</title><p>Results. Two experimental installations for sensors have been developed. The first one is for detection of ethanol vapour by ZnO/ZnO:Cu, ZnO/ZnO:CuO, ZnO/ZnO:Fe junction structures. The second installation was for Pseudomonas putida suspension detection in gas phase by ZnO/ZnO:Fe junction structure. We discovered that ZnO/ZnO:Fe structure, has the lowest operation temperature of 200 °C to ethanol vapour. For this structure, the potential difference has a negative value and decreases with increasing the amount of the pulverized bacteria.</p></sec><sec><title>Conclusion</title><p>Conclusion. We discovered that ZnO/ZnO:Fe structure, has the lowest operation temperature of 200 °C. This operation temperature is a bit higher than operation temperature of at which some very novel sensing structures shows the maximum sensitivity.</p></sec></abstract><trans-abstract xml:lang="en"><sec><title>Introduction</title><p>Introduction. Metal oxide semiconductor sensors have many advantages. But their working temperature is still high and their sensitivities are frequently low. In the current work, I present the results from investigation of sensing ability of new kind of potentiometric solid state gas sensor.</p></sec><sec><title>Aim</title><p>Aim. The main goal of this work is investigation of the temperature dependence in the flow of air and in ethanol vapour mixture of the investigated junction structures. Also, we investigated at fixed temperature the dependence of the thermoelectric force from the ethanol vapour concentration at possible low operation temperature. For the structure, which shows the lowest operation temperature to ethanol vapour, we investigate the ability to detect Pseudomonas putida suspension.</p></sec><sec><title>Materials and methods</title><p>Materials and methods. In this work, the sensitivity to ethanol vapour and Pseudomonas putida suspension were investigated by measuring the thermoelectric force (the voltage) appearing of the structures by standart voltmeters.</p></sec><sec><title>Results</title><p>Results. Two experimental installations for sensors have been developed. The first one is for detection of ethanol vapour by ZnO/ZnO:Cu, ZnO/ZnO:CuO, ZnO/ZnO:Fe junction structures. The second installation was for Pseudomonas putida suspension detection in gas phase by ZnO/ZnO:Fe junction structure. We discovered that ZnO/ZnO:Fe structure, has the lowest operation temperature of 200 °C to ethanol vapour. For this structure, the potential difference has a negative value and decreases with increasing the amount of the pulverized bacteria.</p></sec><sec><title>Conclusion</title><p>Conclusion. We discovered that ZnO/ZnO:Fe structure, has the lowest operation temperature of 200 °C. This operation temperature is a bit higher than operation temperature of at which some very novel sensing structures shows the maximum sensitivity.</p></sec></trans-abstract><kwd-group xml:lang="ru"><kwd>Nanostructured ZnO thin films</kwd><kwd>Ga and Cu doped ZnO thin films</kwd><kwd>CuO doped ZnO nanowires</kwd><kwd>Fe doped ZnO thin films</kwd><kwd>Ethanol gas sensor and Bacteria detection</kwd></kwd-group><kwd-group xml:lang="en"><kwd>Nanostructured ZnO thin films</kwd><kwd>Ga and Cu doped ZnO thin films</kwd><kwd>CuO doped ZnO nanowires</kwd><kwd>Fe doped ZnO thin films</kwd><kwd>Ethanol gas sensor and Bacteria detection</kwd></kwd-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">Wolkenstein F. F. Electronic Processes at the Surface of SemiconductorsDuring the Chemosorptions. 1st ed. Moscow, Nauka, 1987, 432 p. 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