Download or read book Laser Fabrication of High Temperature Thin Film Sensors for Gas Turbines written by Dongfang Yang and published by . This book was released on 2008 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Advances in Thin Film Sensor Technologies for Engine Applications written by Jih-Fen Lei and published by . This book was released on 1997 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: Presented at the International Gas Turbine & Aeroegine Congress & Exhibition, Orlando, FL, Jun 2-Jun 5, 1997.

Download or read book Thin film Temperature Sensors for Gas Turbines written by Shiva Prakash and published by . This book was released on 1987 with total page 302 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Synthesis Fabrication and Surface Modification of Nanocrystalline Nickel Oxide for Electronic Gas Sensors written by Amir Masoud Soleimanpour and published by . This book was released on 2013 with total page 143 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recently, metal oxide gas sensors have attracted much attention in connection with monitoring of combustible and toxic gases because of their higher sensitivity, fast response and recovery times, low power consumption, and low fabrication cost. Nickel oxide (NiO) is a wide band gap and p-type semiconductor with stable chemical and physical properties. NiO has been recognized as one of the most promising material for optical, electrical and gas sensor application owing to its electronic and catalytic properties. NiO is synthesized using different techniques, such as pulsed laser deposition, RF sputtering, electrochemical deposition and sol-gel. The focus of this research was to synthesize and characterize the gas sensing behavior of nickel oxide metal oxide gas sensors. Thin films of nickel oxide synthesized by a sol-gel method have fine nanostructured grains with a high surface to volume ratio, which is beneficial for gas sensor applications. The effect of thickness, fabricating technique, operating temperature, post laser irradiation and metallization on the gas sensing behavior of nickel oxide have been studied. The microstructure, optical and electrical properties of coated film were studied by XRD, SEM, TEM, EDAX, XPS, UV-Vis spectrometer. The gas sensing properties of NiO based sensors were studied for different explosive and hazardous gases as a function of gas concentration and operating temperature. The dependence of fabrication method, film thickness and operating temperature on the hydrogen gas sensing behavior of NiO thin films was investigated. It was observed that the samples with multi-step annealing possessed smaller grain size, higher porosity and higher gas sensing performance. The sample with lower thickness showed better gas sensing performance in all operating temperatures. Moreover, the operating temperature was an important parameter for nickel oxide thin film, and the maximum gas sensor response was recorded at 175oC for hydrogen gas. The effect of post laser irradiation on the gas sensing property of NiO was investigated using Nd:YVO4 laser with a wavelength of 532 nm in different power levels. After laser irradiation, the microstructure, crystallinity and conductivity of the thin films were changed. Results indicated that the irradiated sample with specific power showed better gas sensing performance for hydrogen. Also, the gas sensor response decreased using laser irradiation on the sample. As a result, laser irradiation is an additional tool for tuning the gas sensing behavior of nickel oxide gas sensor. Later, the nickel oxide film was tested for other reducing gases, such as CH4, NH3, and in a mixed gas environment at different operating temperatures. These measurements were conducted to study the selectivity of nickel oxide gas sensor. It was found that the NiO thin film showed a relatively high response to a low concentration of ammonia gas (25 ppm) at a relatively low operating temperature. Instead, the sample showed a relatively low response to methane gas compared to hydrogen and ammonia in the same concentration level. Besides, the gas response of the device at different operating temperature was studied for reducing gases. The film showed a maximum sensitivity for methane and hydrogen gases at 175oC, and the highest response was recorded at 150oC for ammonia gas. These findings are valuable to design selective gas sensors. Finally, Pt decorated sample was tested for various concentrations of hydrogen gas at different operating temperature. The gas sensing property of the film was improved significantly due to the catalyst effect of Pt particles on the surface of metal oxide. Pt decorated sample increased the hydrogen sensing property of nickel oxide by decreasing the energy needed for splitting H2 or O2 molecules on the surface of metal oxide. This study shows several important parameters for nickel oxide gas sensors and it is expected that these techniques can be used to improve the gas sensing performance of different metal oxide gas sensor devices in the future. Collected data at various operating temperatures and gas mixtures can be used to design more selective gas sensors. More detailed research is necessary to establish a general rule for other metal oxide thin films.

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 692 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Experimental Investigations of Nanosceond Pulsed Laser Micromachining of Metal Using Thin Film Microsensors written by Hong Seok Choi and published by . This book was released on 2007 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Enhancement of Nanocrystalline Zinc Oxide Based Electronic Gas Sensor by Surface Modification written by Yue Hou and published by . This book was released on 2014 with total page 173 pages. Available in PDF, EPUB and Kindle. Book excerpt: The increasing concerns of industrial safety, chemical control and environmental pollution are spurring demand for high performance gas sensors. Growing use of gas sensors is making gas sensors on demand. After decades of research and development activities, semiconductor based gas sensors are now used in a variety of applications. However, challenges still remain in the area of sensitivity, selectivity, response and recovery speeds and power consumption. Therefore, improvement of metal oxide gas sensors by the incorporation of different technology is important. In this research, modification of metal oxide semiconductor based gas sensor by impurity doping, laser irradiation, and plasma treatment was investigated. Zinc oxide (ZnO) is an n-type semiconductor with a wide direct band gap (~3.3 eV) and large binding energy (~60 meV). Due to its superior electrical properties and chemical stability, ZnO has been considered one of the most promising materials for gas sensor applications. ZnO thin films have been fabricated by different techniques, such as rf magnetron sputtering, pulsed laser deposition, molecular beam epitaxy, and sol-gel. Sol-gel is a powerful alternative for vacuum deposition. The purpose of this research was to enhance properties and gas sensor performance of nanocrystalline so-gel derived ZnO thin films via surface modification techniques. The effects of process conditions, impurity doping, laser irradiation, laser doping and plasma treatment on properties and gas sensor performance were investigated. The gas sensor performance of ZnO thin films was investigated at different operating temperatures for various reducing and oxidizing gases such as H2, NH3, CH4 and NOx. Al-doped ZnO thin films were prepared using the sol-gel process by changing the Al concentration from 0 to 5.0 at% using two different Zn precursors. It was found that 3.0 at% Al-doped ZnO films had optimum properties such as high electrical conductivity, crystallinity, high sensing response and short response time for ZnO films derived with both Zn precursors. Ga-doped ZnO thin films were also presented by changing the concentration of Ga from 0.1 to 1.0 at%. The gas sensing behavior was investigated at an operating temperature of 130oC. It was found that the 0.3 at% Ga-doped ZnO thin film sensor had more than a 40% higher sensing response and a shorter response time than the sensors made with as-deposited films. Laser irradiation was utilized as a novel heat treatment method in this dissertation. A pulsed laser system with a wavelength of 532 nm was used as the irradiation source. Laser irradiation produced two kinds of Al-doped ZnO films depending on the laser energy level. The impact of laser irradiation was also varied according to the film thickness. The Al-doped ZnO sensors exhibited enhanced sensor performance with optimum laser fluence compared with that of as-deposited sensors. The results suggested that the crystallinity of the Al-doped ZnO thin films was essential to achieve an optimum gas detection capability. A laser doping process using a pre-deposited Al precursor layer for ZnO thin films was also investigated. Plasma treatment was utilized in the research with the intention to adjust the number of intrinsic defects in ZnO films. Both O2 and H2 plasmas were carried out with the treatment time varying from 3 to 15 min. The gas sensor performance was investigated for NH3 and NOx at various concentrations. An improvement of more than 50% in sensing response was observed with the optimum treatment time for NH3 detection. The impact of H2 plasma treatment of ZnO sensors on its gas sensor performance was also studied. The selectivity was studied for a likelihood mixture of reducing gases. The results indicated that ZnO sensors had a low detection limit towards NH3. It was found that the selectivity of these reducing gases was in the order of NH3> H2> CH4. However, unless high concentration of NH3 exposure is a factor, ZnO sensors are selective respond to H2. Furthermore, the ZnO sensors are also capable of discriminating different gases such as NH3, H2, CH4 and NOx. This research involves different techniques, which have been employed on the ZnO thin film based gas sensors in order to enhance the gas sensing characteristics such as sensing response and response time. As expected, the ZnO sensors exhibited high response, short response time and decent selectivity toward target gases with optimum treatment conditions. The results also suggested that the ZnO sensors were capable of detecting ppm level gases at relatively low operating temperature range (100 ~ 200oC), which is beneficial in many applications. Therefore, these techniques can be utilized to manufacture gas sensors using metal oxide semiconductors.

Download or read book Nanostructured Gas Sensors written by Ankur Gupta and published by CRC Press. This book was released on 2023-01-06 with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanostructured materials exhibit distinct properties by virtue of their nanoscale morphological variations, which open up endless possibilities to investigate unexplored and interesting applications. This textbook broadly covers the fabrication and characterization of nanostructured films and exploration of their gas-sensing applications. It presents the fundamentals of gas-sensing technology and a comprehensive study on smart gas sensing technology. Readers will find basics, analytical techniques, nanotechnology-enabled experimental findings, and future directions of smart gas-sensing technology at one place. Through the inclusion of up-to-date experimental knowledge of synthesis, processing, and application development, the book is suitable for academics at all levels.

Download or read book NASA Technical Memorandum written by and published by . This book was released on 1994 with total page 492 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Energy Research Abstracts written by and published by . This book was released on 1993 with total page 906 pages. Available in PDF, EPUB and Kindle. Book excerpt: Semiannual, with semiannual and annual indexes. References to all scientific and technical literature coming from DOE, its laboratories, energy centers, and contractors. Includes all works deriving from DOE, other related government-sponsored information, and foreign nonnuclear information. Arranged under 39 categories, e.g., Biomedical sciences, basic studies; Biomedical sciences, applied studies; Health and safety; and Fusion energy. Entry gives bibliographical information and abstract. Corporate, author, subject, report number indexes.

Download or read book Semiconductor Nanocrystals and Metal Nanoparticles written by Tupei Chen and published by CRC Press. This book was released on 2016-10-14 with total page 526 pages. Available in PDF, EPUB and Kindle. Book excerpt: Semiconductor nanocrystals and metal nanoparticles are the building blocks of the next generation of electronic, optoelectronic, and photonic devices. Covering this rapidly developing and interdisciplinary field, the book examines in detail the physical properties and device applications of semiconductor nanocrystals and metal nanoparticles. It begins with a review of the synthesis and characterization of various semiconductor nanocrystals and metal nanoparticles and goes on to discuss in detail their optical, light emission, and electrical properties. It then illustrates some exciting applications of nanoelectronic devices (memristors and single-electron devices) and optoelectronic devices (UV detectors, quantum dot lasers, and solar cells), as well as other applications (gas sensors and metallic nanopastes for power electronics packaging). Focuses on a new class of materials that exhibit fascinating physical properties and have many exciting device applications. Presents an overview of synthesis strategies and characterization techniques for various semiconductor nanocrystal and metal nanoparticles. Examines in detail the optical/optoelectronic properties, light emission properties, and electrical properties of semiconductor nanocrystals and metal nanoparticles. Reviews applications in nanoelectronic devices, optoelectronic devices, and photonic devices.

Download or read book Printed Flexible Sensors written by Anindya Nag and published by Springer. This book was released on 2019-03-11 with total page 205 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents recent advances in the design, fabrication and implementation of flexible printed sensors. It explores a range of materials for developing the electrode and substrate parts of the sensors, on the basis of their electrical and mechanical characteristics. The sensors were processed using laser cutting and 3D printing techniques, and the sensors developed were employed in a number of healthcare, environmental and industrial applications, including: monitoring of physiological movements, respiration, salinity and nitrate measurement, and tactile sensing. The type of sensor selected for each application depended on its dimensions, robustness and sensitivity. The sensors fabricated were also embedded in an IoT-based system, allowing them to be integrated into real-time applications.

Download or read book Thin Film Coatings written by Fredrick Madaraka Mwema and published by CRC Press. This book was released on 2022-06-19 with total page 309 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thin Film Coatings: Properties, Deposition, and Applications discusses the holistic subject of conventional and emerging thin film technologies without bias to a specific technology based on the existing literature. It covers properties and delves into the various methods of thin film deposition, including the most recent techniques and a direction for future developments. It also discusses the cutting-edge applications of thin film coatings such as self-healing and smart coatings, biomedical, hybrid, and scalable thin films. Finally, the concept of Industry 4.0 in thin film coating technology is examined. This book: Explores a wide range and is not specific to material and method of deposition Demonstrates the application of thin film coatings in nearly all sectors, such as energy and anti-microbial applications Details the preparation and properties of hybrid and scalable (ultra) thin materials for advanced applications Provides detailed bibliometric analyses on applications of thin film coatings Discusses Industry 4.0 and 3D printing in thin film technology With its broad coverage, this comprehensive reference will appeal to a wide audience of materials scientists and engineers and others studying and developing advanced thin film technologies.

Download or read book International Aerospace Abstracts written by and published by . This book was released on 1998 with total page 980 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book MEMS written by Vikas Choudhary and published by CRC Press. This book was released on 2017-12-19 with total page 481 pages. Available in PDF, EPUB and Kindle. Book excerpt: The microelectromechanical systems (MEMS) industry has experienced explosive growth over the last decade. Applications range from accelerometers and gyroscopes used in automotive safety to high-precision on-chip integrated oscillators for reference generation and mobile phones. MEMS: Fundamental Technology and Applications brings together groundbreaking research in MEMS technology and explores an eclectic set of novel applications enabled by the technology. The book features contributions by top experts from industry and academia from around the world. The contributors explain the theoretical background and supply practical insights on applying the technology. From the historical evolution of nano micro systems to recent trends, they delve into topics including: Thin-film integrated passives as an alternative to discrete passives The possibility of piezoelectric MEMS Solutions for MEMS gyroscopes Advanced interconnect technologies Ambient energy harvesting Bulk acoustic wave resonators Ultrasonic receiver arrays using MEMS sensors Optical MEMS-based spectrometers The integration of MEMS resonators with conventional circuitry A wearable inertial and magnetic MEMS sensor assembly to estimate rigid body movement patterns Wireless microactuators to enable implantable MEMS devices for drug delivery MEMS technologies for tactile sensing and actuation in robotics MEMS-based micro hot-plate devices Inertial measurement units with integrated wireless circuitry to enable convenient, continuous monitoring Sensors using passive acousto-electric devices in wired and wireless systems Throughout, the contributors identify challenges and pose questions that need to be resolved, paving the way for new applications. Offering a wide view of the MEMS landscape, this is an invaluable resource for anyone working to develop and commercialize MEMS applications.

Download or read book ERDA Energy Research Abstracts written by United States. Energy Research and Development Administration and published by . This book was released on 1976 with total page 796 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book ERDA Energy Research Abstracts written by United States. Energy Research and Development Administration. Technical Information Center and published by . This book was released on 1976 with total page 788 pages. Available in PDF, EPUB and Kindle. Book excerpt: