Nikolay Samotaev

Metal-oxide gas sensor high-selective to ammonia

Metrological and performance characteristics of a metal-oxide sensor high-selective to ammonia in the presence of methane, carbon monoxide, and water vapors are presented. The specific feature of the design consists in using pulsed sensor heating as the main factor for improved selectivity to ammonia. The ammonia threshold achieved during the pulse-type temperature modulation is 5 × 10−4% vol.

IMS Development at NRNU MEPhI

The MEPhI’s Department of Nano- and Microelectronics was founded in 1965. In 1996, the Department of Nano- and Microelectronics created the first laboratory prototypes of IMS devices. ELNOS (electronic nose) research laboratory has been created since 1999 to develop ion-mobility spectrometry (IMS) technique for detection of ultrasmall amount of substances. During this time, considerable experience in the research and development of IMS was acquired. The four main focuses of application for developed IMS device were detection of explosives (TNT, PETN, RDX, TATP, NG, EGDN, and others), identification of narcotics (heroin, cocaine, amphetamine, methamphetamine, tetrahydrocannabinol, and others), carrying out rescue operations (searching of peoples under destroyed buildings by detection of lactic acid), and diagnostic of human illness (noninvasive detection of diabetes, lung cancer by breath test). For the development of devices for such versatile applications, we need to combine knowledge in the field of chemistry, physics, electronics, programming, and nonstandard microelectronics technology (thick film, ceramic, and MEMS technologies). The synthesis of this knowledge has allowed the ELNOS laboratory in the last 10 years to develop commercially successful samples of IMS devices.

Wireless digital platform for environmental gas monitoring

In this work, we demonstrated an open access Wi-Fi wireless digital platform for environmental gas monitoring based on different types of gas sensors with SPI digital output. The digital platform consist space for four sensors. Used for data exchange between drivers of gas sensors and wireless digital platform, the open data exchange protocol for digital intellectual sensors (DIS) gives possibility to work with any type of gas sensors (electrochemical, metal oxide, thermocatalytic, optical etc.). Developed system architecture of wireless digital platform has also an advantage “hot swap” (PnP) of gas sensors. Visualization of gas concentrations from the wireless digital platform is possible to be received on-line through any web application available on most mobile device (laptop, smart phone, etc.) using widely available free internet browsers (Opera, Google Chrome, etc.) without necessity of downloading any additional user or service software.

Portal Monitor for Human Body Alpha-Radioactive Contamination Control

Pedestrian portal monitor was designed for operational remote control of an alpha radioactive surface contamination of clothing, head and hands of the nuclear industry personnel. The method and device described in this report provides the reliable fast detection of alpha-particles at a distance from the radiation source significantly longer than the alpha-particle run in air by measuring the ions clusters, produced on the tracks of the heave charged particles in the ambient air. The alpha-radioactive pollutants are detected by gasdischarge detectors, opened to the air. It allows quickly controlling the alpha-radioactive contamination by artificial air flux, produced in closed portal, on the irregular surfaces of any indoor objects. This portal monitor may be used for safety inspection as the nuclear plants employers, so at radiation terroristic danger. The experiments shown that portal provides stable remote detecting of low alpha particles radioactivity contamination - about 50 Bq (decays per second) in 5 minutes time.

Software Architecture for Remote Monitoring Systems of Surface Contamination by Alpha Radioactive Isotopes

In this paper, we present alpha-radiation monitoring system software. Detector works in accounting mode that adds some extra features. Possible detector applications such as pedestrian radiation portal monitor or portable alpha contamination dosimeter are presented. Detector is based on air ion method. In view of detector works in accounting mode, it shows high selectivity to alpha particles registration. Alpha selection principle is also shown. Control system and software system are considered in detail.

Digital intellectual sensors for gas analysis system

In this paper, we present development of digital intellectual sensors (DIS) for gas sensor applications based on open digital data exchange protocol using National Standard of Russian Federation for intelligent gas sensor modules. For demonstration possibilities of intellectual sensors in paper described electronic digital driver for oxygen electrochemical gas sensor. In this work a lot of attention gave to questions of standardization and unification for creation a commercially available system for gas analytical instruments industry.

Method and instruments for research of weak microwave field influence on human performance and psychophysiological parameters

There are a lot of new experimental data confirming an essential effect of weak microwave field on human psychophysiological state. This influence may have negative consequences for human-operator fulfilling critical mission. The paper covers a new instrumental method for research of the individual human sensitivity to weak microwave exposure. The volunteers were irradiated by the remotely controlled low-intensity electromagnetic fields source under GSM safety specs. Throughout the investigations, volunteers were performing the psychological tests and their heart rate parameters were registered. The paper presents the architecture of the designed hardware-software system and main modules implementation. It also discusses the results of psychophysiological and humans cardiac reactions to microwave fields. The proposed research method and obtained data may be used for operators state monitoring in Environmental and Structural Monitoring Systems.

Ion Mobility Spectrometer for Rapid Simultaneous Detection of Positive and Negative Ions

Ion Mobility Spectrometry (IMS) is a common technology used for rapid detection of trace amounts of explosives (mostly forming negative ions) and drugs (forming positive ions). Emergency chemically hazardous substances widely used in modern industry. Some emergency chemically hazardous substances form positive ions, others form negative ions. Therefore, for the detection of different substances in real time is required to apply the structure of two IMS-detectors. The article describes a device for the simultaneous detection of ions of both polarities with the ionization source based on a pulsed corona discharge. Authors investigated the advantages and disadvantages of such construction compared to unipolar cell in terms of sensitivity. Experimental results have demonstrated.

Methods for the Self Calibration of Ion Mobility Spectrometer

In transport systems like airports, subway or railway stations widely used ion mobility spectrometers for hazardous toxic gases or explosives traces detection. At the present time ion mobility spectrometers use ionization sources based on the corona discharge. These sources of ionization require frequent calibration, especially if the device is used in the portable embodiment where rapid changes in ambient atmosphere are possible. Error false positives in such systems are critical – the evacuation of passengers transport terminal and emergency calls. To improve situation with false errors we develop system for the self calibration of ion mobility spectrometer based on combination of explosives vapors of and products released during the corona discharge combustion. Designed calibration system is based on corona discharge for ion mobility spectrometry. The control system is integrated into the overall spectrometer structure.

Automotive MEMS sensors based on additive technologies

The application of MEMS devices is one of the recent trends in sensor technology. However, traditional silicon MEMS have some intrinsic limitations, when applied to the monitoring of high temperature/high humidity processes. Thin ceramic films of alumina, zirconia or LTCC fixed on rigid frame made of the same ceramic material in combination with ink and aerosol jet printing of functional materials (heaters, temperature, pressure, gas sensitive elements) provides a cheap, flexible, and high-performance alternative for silicon MEMS devices used as gas sensors, gas flowmeters, lambda probes, bolometric matrices for automotive and general application.