The paper presents the study of adhesive ability of metallic coating applied to the polymer substrate used in the multifunctional coatings of the intelligent architectural films. The studies of the polymer surface treated in argon and oxygen plasma showed that intermetallic layer is formed at the interface, which enhance metal film adhesion to the polymer surface. Technological modes of ion-plasma treatment of a polyimide film have been developed that increase the adhesive ability of the polymer surface, which will improve the performance characteristics of polymer materials and intelligent devices used in integrated systems for providing a comfortable environment.

Sensors used for detecting combustible gases consume significant amounts of power. Energy management for these sensors can become an important issue when they are used as part of a wireless sensor network. This is because of the fact that wireless sensors are usually powered by batteries. Batteries have a finite lifetime and their replacement can take a considerable amount of time in a gas monitoring application where thousands of sensor nodes are deployed to measure the concentration of flammable gases. Moreover, the battery replacement procedure can turn into a more complicated task if the gas monitoring network is located in a harsh environment. Energy harvesting is a method which can increase the operation time of wireless gas sensor networks. In this article, we present a multisource harvesting circuit for a wireless gas sensor node. As for ambient sources, we have chosen solar and wind energy. Energy from ambient sources is stored in supercapacitors which have a capacity of 400 F. We prove that a catalytic gas sensor can operate for 2 days without batteries by using the developed scheme.

Monitoring of hazardous and combustible gases at industrial premises and in the living apartments has been a topic of top priority for a number of decades. Within the last decade a great many of solutions have been proposed including the one relying on the Wireless Sensor Network (WSN) paradigm. Being an autonomous monitoring system, it is essential to guarantee a long lifetime of gas WSN. In this work, we are investigating and implementing a number of heating profiles for catalytic and semiconductor sensors used on board of the wireless sensor nodes to reduce their power consumption. After analyzing the pros and cons of these profiles, we propose the heating profile based on the Pulse Width Modulation (PWM) and the multi stage heating profile. Experimental results demonstrate that the average current consumption of the gas sensor node can be reduced up to 0.76 mA and its power consumption up to 2.54 mW thereby ensuring the autonomous operation of the sensing device for more than one year. (C) 2016 Elsevier B.V. All rights reserved.

A new generation of the light-emitting diodes (LEDs) and photodiodes (PDs) was used recently to develop an open path non-dispersive infrared (NDIR) methane analyzer. The first open path detector prototype was constructed using LEDs for measurement and reference channels, accordingly, and first measurements for methane gas have been performed using optical paths of the order of several meters [3]. The natural gas consists of several first alkanes, mainly methane, and it is important to have a possibility of measuring all of them. In the present work we report the results of NDIR measurements for propane-butane mixture and new measurements of methane using LEDs for measurement and reference channels at 2300 and 1700 nm wavelengths, accordingly. The necessity of the double beam scheme is demonstrated and obtained results for methane and propane-butane mixture are compared.

The use of new infrared LED arrays for NDIR multicomponent gas analysis is considered. Model spectra for bi component gas mixtures are simulated and the concentration reconstruction method is discussed.

Fundamental solutions were developed and energy-saving parameters of a catalytic sensor operation were chosen for using a catalytic sensor in non-volatile wireless sensor networks.Energy-saving mode is based on cyclic method, where every cycle includes short current pulse and the pause between pulses does not exceed regulated by normative documents "response time" for sensors working in continuous mode.To reduce current pulse duration, heating and measuring processes are combined. Two-staged pulse shape was chosen for this, the first stage accelerates heating, the second one is measuring, where we reduce sensor supply voltage and heating temperature, form transient cooling of the sensing element, then measure cooling rate, which is proportional to measured concentration of flammable gas in the air. (C) 2015 The Authors. Published by Elsevier Ltd.

In this work we present the results of design of smart dust sensor platform for combustible gas leakage monitoring. During the design process we took into account a lot of combustible gas sensor specific problems such as their huge power consumption, the necessity to work in explosive environment and sensor parameters degradation. To decrease power consumption we designed specific energy efficient algorithms for measurements. The resulting average power consumption of the node is low enough for one year autonomous lifetime. The methods and algorithms which was designed are very promissing for catalytic combustible gas sensors.

We present results on research and development of catalytic sensors fabricated by planar technology on anodic alumina membranes. A method to detect methane was developed which prevents humidity from affecting the sensor performance and, at the same time, reduces energy consumption. The method, based on step heating the sensor during measurements, enables the power consumption of the sensor to decrease from 35 mW typical of the conventional measurement method to 1.2 mW. As a result, a wireless sensor node equipped with a planar sensor and powered by three AA batteries could operate for about one year. (C) 2013 Elsevier B.V. All rights reserved.

Wireless sensor networks (WSN) have been adopted in various monitoring applications. However, due to the high power consumption of catalytic gas sensors, which enable reliable gas detection, there is a lack of real WSN deployments aimed at the monitoring of combustible gases. This work reports on the evaluation of a WSN deployed in a real operational boiler facility. The WSN consists of nine battery-powered wireless sensor nodes (with an onboard catalytic sensor) controlled by a network coordinator. In this safety critical environment our objective is twofold: (i) guarantee precise and fast sensor response, and (ii) deliver the sensed data from the sensor nodes to the network coordinator safely in case of methane leakage. We first describe the deployment of the WSN and then evaluate the catalytic sensor response under various conditions. Besides, we evaluate the wireless links using the received signal strength indicator (RSSI) and link quality indicator (LQI) metrics. Finally, the experimental results demonstrate that during 5 months of deployment the sensor nodes have been discharged for 22–27%.

In this work we share our experience in the deployment of a Wireless Gas Sensor Network (WGSN) in an operational boiler facility. Our setup is based on a state-of-the-art WGSN platform which ensures reliable gas detection and long–term operation of the network. We first describe the deployment of the network and then evaluate its wireless links using Received Signal Strenght Indicator (RSSI) and Link Quality Indicator (LQI) metrics.

a-C films were deposited by rf-PACVD. Their growth rate, thickness, density and roughness were derived during deposition from time dependent X-ray reflectivity (XRR) at a wavelength of 1.54 Å and at a fixed incidence angle of 1°. It is shown that the film density and surface roughness are not constant at the initial stages of growth. The density increases with increasing film thickness, while the surface roughness depends on the substrate roughness. The evolution of these parameters was measured also while etching the film in oxygen plasma and revealed the smoothing effect brought about by etching to the carbon surface.

Theoretical discussion of surface influence on the properties of nanostructured and nanolayered films is provided. Correlations between mechanical, thermal, chemical and electrical contributions to the nanocomposite properties are shown. Results of investigations of quantum-dimensional multilayer carbon structures are presented. Perspectives of applications of multilayer carbon structures are discussed.

Carbon possesses the unique property to get hybridized in two different forms: the sp(2) and the sp(3). Moreover, carbon easily bonds with hydrogen and other chemical elements to form carbon-based materials with different properties. Here, Er3+-doped amorphous hydrogenated carbon (a-C:H) films deposited via a mixed CVD magnetron sputtering process are studied. The deposition parameters are related to the physical and optical properties of the Er-doped carbon films. (C) 2004 Elsevier B.V. All rights reserved.

physica status solidi (b)Volume 234, Issue 2 p. R1-R3 Rapid Research Note Erbium Photoluminescence in Hydrogenated Amorphous Carbon A.M. Baranov, A.M. Baranov Research Institute of Vacuum Technique, Nagorny Proezd 7, 113105 Moscow, RussiaSearch for more papers by this authorV.V. Sleptsov, V.V. Sleptsov Research Institute of Vacuum Technique, Nagorny Proezd 7, 113105 Moscow, RussiaSearch for more papers by this authorA.A. Nefedov, A.A. Nefedov RRC Kurchatov Institute, Kurchatov Sq. 1, 123182 Moscow, RussiaSearch for more papers by this authorA.E. Varfolomeev, A.E. Varfolomeev RRC Kurchatov Institute, Kurchatov Sq. 1, 123182 Moscow, RussiaSearch for more papers by this authorS.S. Fanchenko, S.S. Fanchenko RRC Kurchatov Institute, Kurchatov Sq. 1, 123182 Moscow, RussiaSearch for more papers by this authorL. Calliari, L. Calliari calliari@itc.it ITC-irst, 38050 Povo (Trento), ItalySearch for more papers by this authorG. Speranza, G. Speranza ITC-irst, 38050 Povo (Trento), ItalySearch for more papers by this authorM. Ferrari, M. Ferrari CNR-IFN, CSMFO Group, 38050 Povo (Trento), ItalySearch for more papers by this authorA. Chiasera, A. Chiasera INFM, Dip. Fisica Universita di Trento, CSMFO Group, 38050 Povo (Trento), ItalySearch for more papers by this author A.M. Baranov, A.M. Baranov Research Institute of Vacuum Technique, Nagorny Proezd 7, 113105 Moscow, RussiaSearch for more papers by this authorV.V. Sleptsov, V.V. Sleptsov Research Institute of Vacuum Technique, Nagorny Proezd 7, 113105 Moscow, RussiaSearch for more papers by this authorA.A. Nefedov, A.A. Nefedov RRC Kurchatov Institute, Kurchatov Sq. 1, 123182 Moscow, RussiaSearch for more papers by this authorA.E. Varfolomeev, A.E. Varfolomeev RRC Kurchatov Institute, Kurchatov Sq. 1, 123182 Moscow, RussiaSearch for more papers by this authorS.S. Fanchenko, S.S. Fanchenko RRC Kurchatov Institute, Kurchatov Sq. 1, 123182 Moscow, RussiaSearch for more papers by this authorL. Calliari, L. Calliari calliari@itc.it ITC-irst, 38050 Povo (Trento), ItalySearch for more papers by this authorG. Speranza, G. Speranza ITC-irst, 38050 Povo (Trento), ItalySearch for more papers by this authorM. Ferrari, M. Ferrari CNR-IFN, CSMFO Group, 38050 Povo (Trento), ItalySearch for more papers by this authorA. Chiasera, A. Chiasera INFM, Dip. Fisica Universita di Trento, CSMFO Group, 38050 Povo (Trento), ItalySearch for more papers by this author First published: 06 November 2002 https://doi.org/10.1002/1521-3951(200211)234:23.0.CO;2-6Citations: 6AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article.Citing Literature Volume234, Issue2November 2002Pages R1-R3 RelatedInformation

The photoelectrochemical behavior of amorphous hydrogenated carbon (a-C:H) thin-film electrodes on tungsten substrates is studied in 0.5 M H2SO4 solution. The a-C:H films, 50-250-nm thick, are grown by the ion-source deposition and magnetron sputtering. Cathodic and anodic photocurrent are observed under cathodic and anodic polarization, respectively, which is characteristic of insulating electrodes or intrinsic semiconductors. The optical band gap width for a-C:H is determined from the photocurrent spectra; it somewhat varies, depending on the conditions of film growth. A tungsten oxide interlayer forms between an a-C:H film and tungsten substrate under strong anodic polarization, which results in the carbon film detachment.

In this paper we describe the system developed on the basis of plasma beam discharge producing high density plasma (10(10)-10(13) cm(-3)). The system allows the formation of charged-particle flows (10-100 mA cm(-2)) at an energy of 60-200 eV onto a treated surface.We have presented results obtained for the diamond-like carbon films produced by this system. It was shown that the him resistivity increased from 10(8) to 10(12) Omega cm, and the optical band gap from 2.4 to 3.2 eV, depending on the type of charged particles (ions or electrons) incident on the grown layer surface. The addition of oxygen (up to 20%) to the original working gas permits the deposition of hard transparent diamond-like carbon films with a band gap of 3.5 eV.

Amorphous carbon (a-C:H) films of different thicknesses were grown on tungsten substrates by ion-plasma decomposition or magnetron sputtering. The behaviour of different specimens, corresponding to distinct growth conditions, was investigated in 0.5 M H2SO4 solution by photoelectrochemical techniques. Depending on the electrode potential, both anodic and cathodic photocurrents were detected owing to an intrinsic semiconductor-like or insulating behaviour of the samples. Different optical gap values were measured for samples grown in different conditions. The influence of the amorphous nature of the films on their behaviour is also briefly discussed. Evidence was also obtained for the growth, under anodic polarization, of an anodic tungsten oxide underlying the a-C:H film which results in the detachment of the amorphous carbon film from the metallic substrate at high potentials.