WorldWideScience

Sample records for technology rtt microwave

  1. Hybrid Microwave Technology

    International Nuclear Information System (INIS)

    Wicks, G.G.

    2001-01-01

    A team associated with a Federal Laboratory, academia, and industry has been actively developing new microwave technology for treatment and remediation of a variety of potentially hazardous materials for almost a decade. This collaboration has resulted in unique equipment and processes with potential applicability to many fields, including disposition of electronic circuitry and components, medical wastes, radioactive materials and recycling of used tires

  2. Microwave mixer technology and applications

    CERN Document Server

    Henderson, Bert

    2013-01-01

    Although microwave mixers play a critical role in wireless communication and other microwave applications employing frequency conversion circuits, engineers find that most books on this subject emphasize theoretical aspects, rather than practical applications. That's about to change with the forthcoming release of Microwave Mixer Technology and Applications. Based on a review of over one thousand patents on mixers and frequency conversion, authors Bert Henderson and Edmar Camargo have written a comprehensive book for mixer designers who want solid ideas for solving their own design challenges.

  3. An RTT-Aware Virtual Machine Placement Method

    Directory of Open Access Journals (Sweden)

    Li Quan

    2017-12-01

    Full Text Available Virtualization is a key technology for mobile cloud computing (MCC and the virtual machine (VM is a core component of virtualization. VM provides a relatively independent running environment for different applications. Therefore, the VM placement problem focuses on how to place VMs on optimal physical machines, which ensures efficient use of resources and the quality of service, etc. Most previous work focuses on energy consumption, network traffic between VMs and so on and rarely consider the delay for end users’ requests. In contrast, the latency between requests and VMs is considered in this paper for the scenario of optimal VM placement in MCC. In order to minimize average RTT for all requests, the round-trip time (RTT is first used as the metric for the latency of requests. Based on our proposed RTT metric, an RTT-Aware VM placement algorithm is then proposed to minimize the average RTT. Furthermore, the case in which one of the core switches does not work is considered. A VM rescheduling algorithm is proposed to keep the average RTT lower and reduce the fluctuation of the average RTT. Finally, in the simulation study, our algorithm shows its advantage over existing methods, including random placement, the traffic-aware VM placement algorithm and the remaining utilization-aware algorithm.

  4. Microwave waste processing technology overview

    Energy Technology Data Exchange (ETDEWEB)

    Petersen, R.D.

    1993-02-01

    Applications using microwave energy in the chemical processing industry have increased within the last ten years. Recently, interest in waste treatment applications process development, especially solidification, has grown. Microwave waste processing offers many advantages over conventional waste treatment technologies. These advantages include a high density, leach resistant, robust waste form, volume and toxicity reduction, favorable economics, in-container treatment, good public acceptance, isolated equipment, and instantaneous energy control. The results from the {open_quotes}cold{close_quotes} demonstration scale testing at the Rocky Flats nuclear weapons facility are described. Preliminary results for a transuranic (TRU) precipitation sludge indicate that volume reductions of over 80% are achievable over the current immobilization process. An economic evaluation performed demonstrated cost savings of $11.68 per pound compared to the immobilization process currently in use on wet sludge.

  5. Microwave waste processing technology overview

    International Nuclear Information System (INIS)

    Petersen, R.D.

    1993-02-01

    Applications using microwave energy in the chemical processing industry have increased within the last ten years. Recently, interest in waste treatment applications process development, especially solidification, has grown. Microwave waste processing offers many advantages over conventional waste treatment technologies. These advantages include a high density, leach resistant, robust waste form, volume and toxicity reduction, favorable economics, in-container treatment, good public acceptance, isolated equipment, and instantaneous energy control. The results from the open-quotes coldclose quotes demonstration scale testing at the Rocky Flats nuclear weapons facility are described. Preliminary results for a transuranic (TRU) precipitation sludge indicate that volume reductions of over 80% are achievable over the current immobilization process. An economic evaluation performed demonstrated cost savings of $11.68 per pound compared to the immobilization process currently in use on wet sludge

  6. MICROWAVE TECHNOLOGY CHEMICAL SYNTHESIS APPLICATIONS

    Science.gov (United States)

    Microwave-accelerated chemical syntheses in various solvents as well as under solvent-free conditions have witnessed an explosive growth. The technique has found widespread application predominantly exploiting the inexpensive unmodified household microwave (MW) ovens although th...

  7. Microwave Tissue Ablation: Biophysics, Technology and Applications

    Science.gov (United States)

    2010-01-01

    Microwave ablation is an emerging treatment option for many cancers, cardiac arrhythmias and other medical conditions. During treatment, microwaves are applied directly to tissues to produce rapid temperature elevations sufficient to produce immediate coagulative necrosis. The engineering design criteria for each application differ, with individual consideration for factors such as desired ablation zone size, treatment duration, and procedural invasiveness. Recent technological developments in applicator cooling, power control and system optimization for specific applications promise to increase the utilization of microwave ablation in the future. This article will review the basic biophysics of microwave tissue heating, provide an overview of the design and operation of current equipment, and outline areas for future research for microwave ablation. PMID:21175404

  8. Microwave plasma emerging technologies for chemical processes

    NARCIS (Netherlands)

    de la Fuente, Javier F.; Kiss, Anton A.; Radoiu, Marilena T.; Stefanidis, Georgios D.

    2017-01-01

    Microwave plasma (MWP) technology is currently being used in application fields such as semiconductor and material processing, diamond film deposition and waste remediation. Specific advantages of the technology include the enablement of a high energy density source and a highly reactive medium,

  9. Applications of microwave radiation environmental remediation technologies

    International Nuclear Information System (INIS)

    Krause, T.R.; Helt, J.E.

    1993-01-01

    A growing number of environmental remediation technologies (e.g., drying, melting, or sintering) utilize microwave radiation as an integral part of the process. An increasing number of novel applications, such as sustaining low-temperature plasmas or enhancing chemical reactivity, are also being developed. An overview of such technologies being developed by the Department of Energy is presented. A specific example being developed at Argonne National Laboratory, microwave-induced plasma reactors for the destruction of volatile organic compounds, is discussed in more detail

  10. [Application of microwave irradiation technology to the field of pharmaceutics].

    Science.gov (United States)

    Zhang, Xue-Bing; Shi, Nian-Qiu; Yang, Zhi-Qiang; Wang, Xing-Lin

    2014-03-01

    Microwaves can be directly transformed into heat inside materials because of their ability of penetrating into any substance. The degree that materials are heated depends on their dielectric properties. Materials with high dielectric loss are more easily to reach a resonant state by microwaves field, then microwaves can be absorbed efficiently. Microwave irradiation technique with the unique heating mechanisms could induce drug-polymer interaction and change the properties of dissolution. Many benefits such as improving product quality, increasing energy efficiency and reducing times can be obtained by microwaves. This paper summarized characteristics of the microwave irradiation technique, new preparation techniques and formulation process in pharmaceutical industry by microwave irradiation technology. The microwave technology provides a new clue for heating and drying in the field of pharmaceutics.

  11. Review of Microwave Photonics Technique to Generate the Microwave Signal by Using Photonics Technology

    Science.gov (United States)

    Raghuwanshi, Sanjeev Kumar; Srivastav, Akash

    2017-12-01

    Microwave photonics system provides high bandwidth capabilities of fiber optic systems and also contains the ability to provide interconnect transmission properties, which are virtually independent of length. The low-loss wide bandwidth capability of optoelectronic systems makes them attractive for the transmission and processing of microwave signals, while the development of high-capacity optical communication systems has required the use of microwave techniques in optical transmitters and receivers. These two strands have led to the development of the research area of microwave photonics. So, we can considered microwave photonics as the field that studies the interaction between microwave and optical waves for applications such as communications, radars, sensors and instrumentations. In this paper we have thoroughly reviewed the microwave generation techniques by using photonics technology.

  12. Microwaves integrated circuits: hybrids and monolithics - fabrication technology

    International Nuclear Information System (INIS)

    Cunha Pinto, J.K. da

    1983-01-01

    Several types of microwave integrated circuits are presented together with comments about technologies and fabrication processes; advantages and disadvantages in their utilization are analysed. Basic structures, propagation modes, materials used and major steps in the construction of hybrid thin film and monolithic microwave integrated circuits are described. Important technological applications are revised and main activities of the microelectronics lab. of the University of Sao Paulo (Brazil) in the field of hybrid and monolithic microwave integrated circuits are summarized. (C.L.B.) [pt

  13. A New TCP Congestion Control Supporting RTT-Fairness

    Science.gov (United States)

    Ogura, Kazumine; Nemoto, Yohei; Su, Zhou; Katto, Jiro

    This paper focuses on RTT-fairness of multiple TCP flows over the Internet, and proposes a new TCP congestion control named “HRF (Hybrid RTT-Fair)-TCP”. Today, it is a serious problem that the flows having smaller RTT utilize more bandwidth than others when multiple flows having different RTT values compete in the same network. This means that a user with longer RTT may not be able to obtain sufficient bandwidth by the current methods. This RTT fairness issue has been discussed in many TCP papers. An example is CR (Constant Rate) algorithm, which achieves RTT-fairness by multiplying the square of RTT value in its window increment phase against TCP-Reno. However, the method halves its windows size same as TCP-Reno when a packet loss is detected. This makes worse its efficiency in certain network cases. On the other hand, recent proposed TCP versions essentially require throughput efficiency and TCP-friendliness with TCP-Reno. Therefore, we try to keep these advantages in our TCP design in addition to RTT-fairness. In this paper, we make intuitive analytical models in which we separate resource utilization processes into two cases: utilization of bottleneck link capacity and that of buffer space at the bottleneck link router. These models take into account three characteristic algorithms (Reno, Constant Rate, Constant Increase) in window increment phase where a sender receives an acknowledgement successfully. Their validity is proved by both simulations and implementations. From these analyses, we propose HRF-TCP which switches two modes according to observed RTT values and achieves RTT fairness. Experiments are carried out to validate the proposed method. Finally, HRF-TCP outperforms conventional methods in RTT-fairness, efficiency and friendliness with TCP-Reno.

  14. NOAA JPSS Microwave Integrated Retrieval System (MIRS) Advanced Technology Microwave Sounder (ATMS) Sounding Products from NDE

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains temperature and humidity profiles from the NOAA Microwave Integrated Retrieval System (MIRS) using sensor data from the Advanced Technology...

  15. Lithographic technology for microwave integrated circuits

    OpenAIRE

    Shepherd, PR; Evans, PSA; Ramsey, BJ; Harrison, DJ

    1997-01-01

    Conductive lithographic films (CLFs) have been developed primarily as substitutes for resin/laminate boards, which share properties with the metallisation patterns used in planar microwave integrated circuits (MICs). The authors examine the microwave properties of the films and show that, although the losses are greater, they have potential as an alternative to the traditional manufacturing process of MICs.

  16. Photoinduced spin polarization and microwave technology

    International Nuclear Information System (INIS)

    Antipov, Sergey; Poluektov, Oleg; Schoessow, Paul; Kanareykin, Alexei; Jing, Chunguang

    2013-01-01

    We report here on studies of optically pumped active microwave media based on various fullerene derivatives, with an emphasis on the use of these materials in microwave electronics. We have investigated a class of optically excited paramagnetic materials that demonstrate activity in the X-band as candidate materials. We found that a particular fullerene derivative, Phenyl-C 61 -butyric acid methyl ester (PCBM), produced the largest electron paramagnetic resonance (EPR) emission signal compared to other organic compounds that have been suggested for use as microwave active materials. We also studied the effects of concentration, temperature, solvent etc. on the activity of the material. In these experiments, EPR studies using a commercial spectrometer were followed up by measurements of an RF signal reflected from a resonator loaded with the PCBM-based material. The activity was directly demonstrated through the change in the quality factor and RF coupling between the resonator and waveguide feed. At the inception of these experiments the primary interest was the development of a microwave PASER. The PASER (particle acceleration by stimulated emission of radiation [1]) is a novel acceleration concept that is based on the direct energy transfer from an active medium to a charged particle beam. While the previous work on the PASER has emphasized operations at infrared or visible wavelengths, operating in the microwave regime has significant advantages in terms of the less stringent quality requirements placed on the electron beam provided an appropriate microwave active medium can be found. This paper is focused on our investigation of the possibility of a PASER operating in the microwave frequency regime [2] using active paramagnetic materials. While a high level of gain for PCBM was demonstrated compared to other candidate materials, dielectric losses and quenching effects were found to negatively impact its performance for PASER applications. We present results on

  17. Development of glass fibre reinforced composites using microwave heating technology

    Science.gov (United States)

    Köhler, T.; Vonberg, K.; Gries, T.; Seide, G.

    2017-10-01

    Fibre reinforced composites are differentiated by the used matrix material (thermoplastic versus duroplastic matrix) and the level of impregnation. Thermoplastic matrix systems get more important due to their suitability for mass production, their good shapeability and their high impact resistance. A challenge in the processing of these materials is the reduction of the melt flow paths of the thermoplastic matrix. The viscosity of molten thermoplastic material is distinctly higher than the viscosity of duroplastic material. An approach to reduce the flow paths of the thermoplastic melt is given by a commingling process. Composites made from commingling hybrid yarns consist of thermoplastic and reinforcing fibres. Fabrics made from these hybrid yarns are heated and consolidated by the use of heat pressing to form so called organic sheets. An innovative heating system is given by microwaves. The advantage of microwave heating is the volumetric heating of the material, where the energy of the electromagnetic radiation is converted into thermal energy inside the material. In this research project microwave active hybrid yarns are produced and examined at the Institute for Textile Technology of RWTH Aachen University (ITA). The industrial research partner Fricke und Mallah Microwave Technology GmbH, Peine, Germany develops an innovative pressing systems based on a microwave heating system. By implementing the designed microwave heating technology into an existing heat pressing process, FRTCs are being manufactured from glass and nanomodified polypropylene fibre woven fabrics. In this paper the composites are investigated for their mechanical and optical properties.

  18. Microwave Technology--Applications in Chemical Synthesis

    Science.gov (United States)

    Microwave heating, being specific and instantaneous, is unique and has found a place for expeditious chemical syntheses. Specifically, the solvent-free reactions are convenient to perform and have advantages over the conventional heating protocols as summarized in the previous se...

  19. A novel symmetrical microwave power sensor based on GaAs monolithic microwave integrated circuit technology

    International Nuclear Information System (INIS)

    Wang, De-bo; Liao, Xiao-ping

    2009-01-01

    A novel symmetrical microwave power sensor based on GaAs monolithic microwave integrated circuit (MMIC) technology is presented in this paper. In this power sensor, the left section inputs the microwave power, while the right section inputs the dc power. Because of the symmetrical structure, this power sensor is created to provide more accurate microwave power measurement capability without mismatch uncertainty and restrain temperature drift. The loss model is built and the loss voltage is 0.8 mV at 20 GHz when the input power is 100 mW. This power sensor is designed and fabricated using GaAs MMIC technology. And it is measured in the frequency range up to 20 GHz with the input power in the −20 dBm to 19 dBm range. Over the 19 dBm dynamic range, the sensitivity can achieve about 0.2 mV mW −1 . The difference between the input powers in the two sections is below 0.1% for equal output voltages. For an amplitude modulation measurement, the carrier frequency is the main factor to influence the measurement results. In short, the key aspect of this power sensor is that the microwave power measurement can be replaced by a dc power measurement with precise wideband

  20. RF and microwave integrated circuit development technology, packaging and testing

    CERN Document Server

    Gamand, Patrice; Kelma, Christophe

    2018-01-01

    RF and Microwave Integrated Circuit Development bridges the gap between existing literature, which focus mainly on the 'front-end' part of a product development (system, architecture, design techniques), by providing the reader with an insight into the 'back-end' part of product development. In addition, the authors provide practical answers and solutions regarding the choice of technology, the packaging solutions and the effects on the performance on the circuit and to the industrial testing strategy. It will also discuss future trends and challenges and includes case studies to illustrate examples. * Offers an overview of the challenges in RF/microwave product design * Provides practical answers to packaging issues and evaluates its effect on the performance of the circuit * Includes industrial testing strategies * Examines relevant RF MIC technologies and the factors which affect the choice of technology for a particular application, e.g. technical performance and cost * Discusses future trends and challen...

  1. Monolithic microwave integrated circuit technology for advanced space communication

    Science.gov (United States)

    Ponchak, George E.; Romanofsky, Robert R.

    1988-01-01

    Future Space Communications subsystems will utilize GaAs Monolithic Microwave Integrated Circuits (MMIC's) to reduce volume, weight, and cost and to enhance system reliability. Recent advances in GaAs MMIC technology have led to high-performance devices which show promise for insertion into these next generation systems. The status and development of a number of these devices operating from Ku through Ka band will be discussed along with anticipated potential applications.

  2. Complementary HFET technology for wireless digital and microwave applications

    Energy Technology Data Exchange (ETDEWEB)

    Baca, A.G.; Zolper, J.C.; Dubbert, D.F. [and others

    1996-09-01

    Development of a complementary heterostructure field effect transistor (CHFET) technology for low-power, mixed-mode digital-microwave applications is presented. Digital CHFET technology with independently optimizable transistors has been shown to operate with 319 ps loaded gate delays at 8.9 fJ. Power consumption is dominated by leakage currents of the p-channel FET, while performance is determined by the characteristics of 0.7 {mu}m gate length devices. As a microwave technology, the nJFET forms the basis of low-power cirucitry without any modification to the digital process. Narrow band amplification with a 0.7x100 {mu}m nJFET has been demonstrated at 2.1-2.4 GHz with gains of 8-10 dB at 1 mW power. These amplifiers showed a minimum noise figure of 2.5 dB. Next generation CHFET transistors with sub 0.5 {mu}m gate lengths have also been developed. Cutoff frequencies of 49 and 11.5 GHz were achieved for n- and p-channel FETs with 0.3 and 0.4 {mu}m gates, respectively. These FETs will enable enhancements in both digital and microwave circuits.

  3. Advanced microwave/millimeter-wave imaging technology

    International Nuclear Information System (INIS)

    Shen, Zuowei; Yang, Lu; Luhmann, N.C. Jr.

    2007-01-01

    Millimeter wave technology advances have made possible active and passive millimeter wave imaging for a variety of applications including advanced plasma diagnostics, radio astronomy, atmospheric radiometry, concealed weapon detection, all-weather aircraft landing, contraband goods detection, harbor navigation/surveillance in fog, highway traffic monitoring in fog, helicopter and automotive collision avoidance in fog, and environmental remote sensing data associated with weather, pollution, soil moisture, oil spill detection, and monitoring of forest fires, to name but a few. The primary focus of this paper is on technology advances which have made possible advanced imaging and visualization of magnetohydrodynamic (MHD) fluctuations and microturbulence in fusion plasmas. Topics of particular emphasis include frequency selective surfaces, planar Schottky diode mixer arrays, electronically controlled beam shaping/steering arrays, and high power millimeter wave local oscillator and probe sources. (author)

  4. Electrically Tuned Microwave Devices Using Liquid Crystal Technology

    Directory of Open Access Journals (Sweden)

    Pouria Yaghmaee

    2013-01-01

    Full Text Available An overview of liquid crystal technology for microwave and millimeter-wave frequencies is presented. The potential of liquid crystals as reconfigurable materials arises from their ability for continuous tuning with low power consumption, transparency, and possible integration with printed and flexible circuit technologies. This paper describes physical theory and fundamental electrical properties arising from the anisotropy of liquid crystals and overviews selected realized liquid crystal devices, throughout four main categories: resonators and filters, phase shifters and delay lines, antennas, and, finally, frequency-selective surfaces and metamaterials.

  5. Monolithic Microwave Integrated Circuit (MMIC) technology for space communications applications

    Science.gov (United States)

    Connolly, Denis J.; Bhasin, Kul B.; Romanofsky, Robert R.

    1987-01-01

    Future communications satellites are likely to use gallium arsenide (GaAs) monolithic microwave integrated-circuit (MMIC) technology in most, if not all, communications payload subsystems. Multiple-scanning-beam antenna systems are expected to use GaAs MMIC's to increase functional capability, to reduce volume, weight, and cost, and to greatly improve system reliability. RF and IF matrix switch technology based on GaAs MMIC's is also being developed for these reasons. MMIC technology, including gigabit-rate GaAs digital integrated circuits, offers substantial advantages in power consumption and weight over silicon technologies for high-throughput, on-board baseband processor systems. For the more distant future pseudomorphic indium gallium arsenide (InGaAs) and other advanced III-V materials offer the possibility of MMIC subsystems well up into the millimeter wavelength region. All of these technology elements are in NASA's MMIC program. Their status is reviewed.

  6. Tunable Microwave Component Technologies for SatCom-Platforms

    Science.gov (United States)

    Maune, Holger; Jost, Matthias; Wiens, Alex; Weickhmann, Christian; Reese, Roland; Nikfalazar, Mohammad; Schuster, Christian; Franke, Tobias; Hu, Wenjuan; Nickel, Matthias; Kienemund, Daniel; Prasetiadi, Ananto Eka; Jakoby, Rolf

    2017-03-01

    Modern communication platforms require a huge amount of switched RF component banks especially made of different filters and antennas to cover all operating frequencies and bandwidth for the targeted services and application scenarios. In contrast, reconfigurable devices made of tunable components lead to a considerable reduction in complexity, size, weight, power consumption, and cost. This paper gives an overview of suitable technologies for tunable microwave components especially for SatCom applications. Special attention is given to tunable components based on functional materials such as barium strontium titanate (BST) and liquid crystal (LC).

  7. Optical technology for microwave applications IV; Proceedings of the Meeting, Orlando, FL, Mar. 28, 29, 1989

    Science.gov (United States)

    Yao, Shi-Kay

    Among the topics discussed at the meeting are high-speed laser and electrooptical technologies, detectors and detector arrays, microwave delay lines, and photon-microwave interactions. In addition, optical link applications are discussed, along with electronic warfare receivers and acoustooptical signal processing. Emphasis is placed on laser diode technology, direct modulation of laser diodes, external electrooptical laser modulation techniques, and microwave fiber-optic delay lines. Attention is given to such optical link applications as multigigahertz links as well as to signal processing for phased-array antennas and channelized microwave receiver technologies.

  8. Monolithic Microwave Integrated Circuits Based on GaAs Mesfet Technology

    Science.gov (United States)

    Bahl, Inder J.

    Advanced military microwave systems are demanding increased integration, reliability, radiation hardness, compact size and lower cost when produced in large volume, whereas the microwave commercial market, including wireless communications, mandates low cost circuits. Monolithic Microwave Integrated Circuit (MMIC) technology provides an economically viable approach to meeting these needs. In this paper the design considerations for several types of MMICs and their performance status are presented. Multifunction integrated circuits that advance the MMIC technology are described, including integrated microwave/digital functions and a highly integrated transceiver at C-band.

  9. Microwave technology for waste management applications including disposition of electronic circuitry

    International Nuclear Information System (INIS)

    Wicks, G.G.; Clark, D.E.; Schulz, R.L.; Folz, D.C.

    1995-01-01

    Microwave technology is being developed nationally and internationally for a variety of environmental remediation purposes. These efforts include treatment and destruction of a vast array of gaseous, liquid and solid hazardous wastes as well as subsequent immobilization of selected components. Microwave technology provides an important contribution to an arsenal of existing remediation methods that are designed to protect the public and environment from undesirable consequences of hazardous materials. Applications of microwave energy for environmental remediation will be discussed. Emphasized will be a newly developed microwave process designed to treat discarded electronic circuitry and reclaim the precious metals within for reuse

  10. Microwave processing for ceramic materials in microsystem technology

    International Nuclear Information System (INIS)

    Rhee, S.

    2002-11-01

    In this study, the applicability of microwaves for sintering of monolithic ceramics and ceramic microcomponents was investigated. Experiments with 2.45 GHz and 30 GHz microwaves were conducted and contrasted to conventional thermal processing. The advantages and disadvantages of microwave processing were then assessed. Nanoscale zirconia and sub-micron lead-zirconate-titanate electroceramics were selected for the evaluation. (orig.)

  11. Microwave photonics technologies supporting high capacity and flexible wireless communications systems

    DEFF Research Database (Denmark)

    Lu, Xiaofeng; Tatarczak, Anna; Rommel, Simon

    2015-01-01

    Emerging 5G wireless systems require technologies for increased capacity, guarantee robustness, low latency and flexibility. We review a number of approaches to provide the above based on microwave photonics and hybrid optical fiber-wireless communication techniques....

  12. Rtt107/Esc4 binds silent chromatin and DNA repair proteins using different BRCT motifs

    Directory of Open Access Journals (Sweden)

    Jockusch Rebecca A

    2006-11-01

    Full Text Available Abstract Background By screening a plasmid library for proteins that could cause silencing when targeted to the HMR locus in Saccharomyces cerevisiae, we previously reported the identification of Rtt107/Esc4 based on its ability to establish silent chromatin. In this study we aimed to determine the mechanism of Rtt107/Esc4 targeted silencing and also learn more about its biological functions. Results Targeted silencing by Rtt107/Esc4 was dependent on the SIR genes, which encode obligatory structural and enzymatic components of yeast silent chromatin. Based on its sequence, Rtt107/Esc4 was predicted to contain six BRCT motifs. This motif, originally identified in the human breast tumor suppressor gene BRCA1, is a protein interaction domain. The targeted silencing activity of Rtt107/Esc4 resided within the C-terminal two BRCT motifs, and this region of the protein bound to Sir3 in two-hybrid tests. Deletion of RTT107/ESC4 caused sensitivity to the DNA damaging agent MMS as well as to hydroxyurea. A two-hybrid screen showed that the N-terminal BRCT motifs of Rtt107/Esc4 bound to Slx4, a protein previously shown to be involved in DNA repair and required for viability in a strain lacking the DNA helicase Sgs1. Like SLX genes, RTT107ESC4 interacted genetically with SGS1; esc4Δ sgs1Δ mutants were viable, but exhibited a slow-growth phenotype and also a synergistic DNA repair defect. Conclusion Rtt107/Esc4 binds to the silencing protein Sir3 and the DNA repair protein Slx4 via different BRCT motifs, thus providing a bridge linking silent chromatin to DNA repair enzymes.

  13. Recent progress on microwave imaging technology and new physics results

    International Nuclear Information System (INIS)

    Tobias, Benjamin; Luhmann, Neville C. Jr.; Domier, Calvin W.

    2011-01-01

    Techniques for visualizing turbulent flow in nature and in the laboratory have evolved over half a millennium from Leonardo da Vinci's sketches of cascading waterfalls to the advanced imaging technologies which are now pervasive in our daily lives. Advancements in millimeter wave imaging have served to usher in a new era in plasma diagnostics, characterized by ever improving 2D, and even 3D, images of complex phenomena in tokamak and stellarator plasmas. Examples at the forefront of this revolution are electron cyclotron emission imaging (ECEI) and microwave imaging reflectometry (MIR). ECEI has proved to be a powerful tool as it has provided immediate physics results following successful diagnostic installations on TEXTOR, ASDEX-U, DIII-D, and KSTAR. Recent results from the MIR system on LHD are demonstrating that this technique has the potential for comparable impact in the diagnosis of electron density fluctuations. This has motivated a recent resurgence in MIR research and development, building on a prototype system demonstrated on TEXTOR, toward the realization of combined ECEI/MIR systems on DIII-D and KSTAR for simultaneous imaging of electron temperature and density fluctuations. The systems discussed raise the standard for fusion plasma diagnostics and present a powerful new capability for the validation of theoretical models and numerical simulations. (author)

  14. Microwave Technology for Waste Management Applications Including Disposition of Electronic Circuitry

    International Nuclear Information System (INIS)

    Wicks, G.G.; Clark, D.E.; Schulz, R.L.

    1998-01-01

    Advanced microwave technology is being developed nationally and internationally for a variety of waste management and environmental remediation purposes. These efforts include treatment and destruction of a vast array of gaseous, liquid and solid hazardous wastes as well as subsequent immobilization of hazardous components into leach resistant forms. Microwave technology provides an important contribution to an arsenal of existing remediation methods that are designed to protect the public and environment from the undesirable consequences of hazardous materials. One application of special interest is the treatment of discarded electronic circuitry using a new hybrid microwave treatment process and subsequent reclamation of the precious metals within

  15. Microfabricated Low-Loss Microwave Switch Integration Technology, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Nuvotronics has developed and optimized the PolyStrataTM process for the fabrication of intricate microwave and millimeter-wave devices. These devices have primarily...

  16. Microwave Irradiation

    Indian Academy of Sciences (India)

    Way to Eco-friendly, Green Chemistry. Rashmi ... The rapid heating of food in the kitchen using microwave ovens ... analysis; application to waste treatment; polymer technology; ... of microwave heating in organic synthesis since the first contri-.

  17. High-power microwave LDMOS transistors for wireless data transmission technologies (Review)

    International Nuclear Information System (INIS)

    Kuznetsov, E. V.; Shemyakin, A. V.

    2010-01-01

    The fields of the application, structure, fabrication, and packaging technology of high-power microwave LDMOS transistors and the main advantages of these devices were analyzed. Basic physical parameters and some technology factors were matched for optimum device operation. Solid-state microwave electronics has been actively developed for the last 10-15 years. Simultaneously with improvement of old devices, new devices and structures are actively being adopted and developed and new semiconductor materials are being commercialized. Microwave LDMOS technology is in demand in such fields as avionics, civil and military radars, repeaters, base stations of cellular communication systems, television and broadcasting transmitters, and transceivers for high-speed wireless computer networks (promising Wi-Fi and Wi-Max standards).

  18. Ultrasonic Spray Drying vs High Vacuum and Microwaves Technology for Blueberries

    Science.gov (United States)

    Candia-Muñoz, N.; Ramirez-Bunster, M.; Vargas-Hernández, Y.; Gaete-Garretón, L.

    Interest in high quality foods: good taste and a high content of nutrients with healthy beneficial effects are increasing. Fruits have good properties but, they are lost because the oxidation process, additionally, for different reasons a 40% of harvested fruit are lost. To conserve the fruit properties an ultrasonic assisted spray dryer was developed and tested, comparing its results with microwave-vacuum drying technology. Results did shown taste, color, smell, particle shape and size distribution better than the conventional one. The antioxidants conservation were quite good except in the anthocyanins, in which the microwave and vacuum technology shown best results.

  19. Microwave Technology for Brain Imaging and Monitoring: Physical Foundations, Potential and Limitations

    DEFF Research Database (Denmark)

    Scapaticci, Rosa; Bjelogrlic, Mina; Tobon Vasquez, Jorge

    2018-01-01

    This chapter provides an introduction to the physical principles underlying the adoption of microwave technology as a biomedical imaging modality for diagnosis and follow-up of neurological diseases and injuries (e.g., stroke, haematoma). In particular, a theoretical analysis, supported...... by numerical simulations and experiments, will be given to describe the physical constraints that arise in this kind of application and the relevant limitations. In addition, we discuss the main aspects to be faced when implementing microwave imaging technology in a clinical scenario, by exploiting a design...

  20. Virtual Screening of Phytochemicals to Novel Target (HAT) Rtt109 in Pneumocystis Jirovecii using Bioinformatics Tools.

    Science.gov (United States)

    Sugumar, Ramya; Adithavarman, Abhinand Ponneri; Dakshinamoorthi, Anusha; David, Darling Chellathai; Ragunath, Padmavathi Kannan

    2016-03-01

    Pneumocystis jirovecii is a fungus that causes Pneumocystis pneumonia in HIV and other immunosuppressed patients. Treatment of Pneumocystis pneumonia with the currently available antifungals is challenging and associated with considerable adverse effects. There is a need to develop drugs against novel targets with minimal human toxicities. Histone Acetyl Transferase (HAT) Rtt109 is a potential therapeutic target in Pneumocystis jirovecii species. HAT is linked to transcription and is required to acetylate conserved lysine residues on histone proteins by transferring an acetyl group from acetyl CoA to form e-N-acetyl lysine. Therefore, inhibitors of HAT can be useful therapeutic options in Pneumocystis pneumonia. To screen phytochemicals against (HAT) Rtt109 using bioinformatics tool. The tertiary structure of Pneumocystis jirovecii (HAT) Rtt109 was modeled by Homology Modeling. The ideal template for modeling was obtained by performing Psi BLAST of the protein sequence. Rtt109-AcCoA/Vps75 protein from Saccharomyces cerevisiae (PDB structure 3Q35) was chosen as the template. The target protein was modeled using Swiss Modeler and validated using Ramachandran plot and Errat 2. Comprehensive text mining was performed to identify phytochemical compounds with antipneumonia and fungicidal properties and these compounds were filtered based on Lipinski's Rule of 5. The chosen compounds were subjected to virtual screening against the target protein (HAT) Rtt109 using Molegro Virtual Docker 4.5. Osiris Property Explorer and Open Tox Server were used to predict ADME-T properties of the chosen phytochemicals. Tertiary structure model of HAT Rtt 109 had a ProSA score of -6.57 and Errat 2 score of 87.34. Structure validation analysis by Ramachandran plot for the model revealed 97% of amino acids were in the favoured region. Of all the phytochemicals subjected to virtual screening against the target protein (HAT) Rtt109, baicalin exhibited highest binding affinity towards the

  1. Wideband Monolithic Microwave Integrated Circuit Frequency Converters with GaAs mHEMT Technology

    DEFF Research Database (Denmark)

    Krozer, Viktor; Johansen, Tom Keinicke; Djurhuus, Torsten

    2005-01-01

    We present monolithic microwave integrated circuit (MMIC) frequency converter, which can be used for up and down conversion, due to the large RF and IF port bandwidth. The MMIC converters are based on commercially available GaAs mHEMT technology and are comprised of a Gilbert mixer cell core...

  2. Optical technology for microwave applications V; Proceedings of the Meeting, Orlando, FL, Apr. 3-5, 1991

    Science.gov (United States)

    Yao, Shi-Kay

    Consideration is given to light modulation technologies, wideband optical links, phased array antenna applications, radar and EW applications, and novel optoelectronic devices and technologies. Particular attention is given to wideband nonlinear optical organic external modulators, ultra-linear electrooptic modulators for microwave fiber-optic communications, coherent optical modulation for antenna remoting, a hybrid optical transmitter for microwave communication, a direct optical phase shifter for phased array systems, acoustooptic architectures for multidimensional phased-array antenna processing, generalized phased-array Bragg interaction in anisotropic crystals, analog optical processing of radio frequency signals, a wideband acoustooptic spectrometer, ring resonators for microwave optoelectronics, optical techniques for microwave monolithic circuit characterization, microwave control using a high-gain bias-free optoelectronic switch, and A/D conversion of microwave signals using a hybrid optical-electronic technique. (For individual items see A93-25727 to A93-25758)

  3. Role of advanced RF/microwave technology and high power switch technology for developing/upgrading compact/existing accelerators

    International Nuclear Information System (INIS)

    Shrivastava, Purushottam

    2001-01-01

    With the advances in high power microwave devices as well as in microwave technologies it has become possible to go on higher frequencies at higher powers as well as to go for newer devices which are more efficient and compact and hence reducing the power needs as well as space and weight requirement for accelerators. New devices are now available in higher frequency spectrum for example at C-Band, X-band and even higher. Also new devices like klystrodes/Higher Order Mode Inductive Output Tubes (HOM IOTs) are now becoming competitors for existing tubes which are in use at present accelerator complexes. The design/planning of the accelerators used for particle physics research, medical accelerators, industrial irradiation, or even upcoming Driver Accelerators for Sub Critical Reactors for nuclear power generation are being done taking into account the newer technologies. The accelerators which use magnetrons, klystrons and similar devices at S-Band can be modified/redesigned with devices at higher frequencies like X-Band. Pulsed accelerators need high power high voltage pulsed modulators whereas CW accelerators need high voltage power supplies for functioning of RF / Microwave tubes. There had been a remarkable growth in the development and availability of solid state switches both for switching the pulsed modulators for microwave tubes as well as for making high frequency switch mode power supplies. Present paper discusses some of the advanced devices/technologies in this field as well as their capability to make advanced/compact/reliable accelerators. Microwave systems developed/under development at Centre for Advanced Technology are also discussed briefly along with some of the efforts done to make them compact. An overview of state of art vacuum tube devices and solid state switch technologies is given. (author)

  4. Microwave power engineering applications

    CERN Document Server

    Okress, Ernest C

    2013-01-01

    Microwave Power Engineering, Volume 2: Applications introduces the electronics technology of microwave power and its applications. This technology emphasizes microwave electronics for direct power utilization and transmission purposes. This volume presents the accomplishments with respect to components, systems, and applications and their prevailing limitations in the light of knowledge of the microwave power technology. The applications discussed include the microwave heating and other processes of materials, which utilize the magnetron predominantly. Other applications include microwave ioni

  5. Planck intermediate results. XXVI. Optical identification and redshifts of Planck clusters with the RTT150 telescope

    DEFF Research Database (Denmark)

    Ade, P. A. R.; Aghanim, N.; Arnaud, M.

    2015-01-01

    We present the results of approximately three years of observations of Planck Sunyaev-Zeldovich (SZ) sources with the Russian-Turkish 1.5m telescope (RTT150), as a part of the optical follow-up programme undertaken by the Planck collaboration. During this time period approximately 20% of all dark...

  6. NOAA JPSS Advanced Technology Microwave Sounder (ATMS) Remapped to Cross-track Infrared Sounder (CrIS) Sensor Data Record (SDR) from IDPS

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Advanced Technology Microwave Sounder (ATMS) is a 22 channel microwave sounder on board the Suomi NPP satellite that provides continuous cross-track scanning in...

  7. Advances in microwaves 8

    CERN Document Server

    Young, Leo

    2013-01-01

    Advances in Microwaves, Volume 8 covers the developments in the study of microwaves. The book discusses the circuit forms for microwave integrated circuits; the analysis of microstrip transmission lines; and the use of lumped elements in microwave integrated circuits. The text also describes the microwave properties of ferrimagnetic materials, as well as their interaction with electromagnetic waves propagating in bounded waveguiding structures. The integration techniques useful at high frequencies; material technology for microwave integrated circuits; specific requirements on technology for d

  8. Microwave technology for waste management applications: Treatment of discarded electronic circuitry

    Energy Technology Data Exchange (ETDEWEB)

    Wicks, G.G. [Westinghouse Savannah River Technology Center, Aiken, SC (United States); Clark, D.E.; Schulz, R.L. [Univ. of Florida, Gainesville, FL (United States)

    1997-01-01

    Significant quantities of hazardous wastes are generated from a multitude of processes and products in today`s society. This waste inventory is not only very large and diverse, but is also growing at an alarming rate. In order to minimize the dangers presented by constituents in these wastes, microwave technologies are being investigated to render harmless the hazardous components and ultimately, to minimize their impact to individuals and the surrounding environment.

  9. Arbitrary waveform generation based on Microwave Photonics Technology for Ultrawideband applications

    OpenAIRE

    Moreno Galué, Vanessa Alejandra

    2017-01-01

    The herein presented Ph.D. dissertation finds its application niche in pulse generation for optical communication schemes, specifically for Ultrawideband (UWB) purposes. In this sense, as the requirements in terms of capacity and bandwidth per user in the field of broadband communication services continuously increase, different technological techniques such as hybrid wireless-optical approaches including UWB systems and close competitors like the Worldwide Interoperability for Microwave Acce...

  10. Advances in gallium arsenide monolithic microwave integrated-circuit technology for space communications systems

    Science.gov (United States)

    Bhasin, K. B.; Connolly, D. J.

    1986-01-01

    Future communications satellites are likely to use gallium arsenide (GaAs) monolithic microwave integrated-circuit (MMIC) technology in most, if not all, communications payload subsystems. Multiple-scanning-beam antenna systems are expected to use GaAs MMIC's to increase functional capability, to reduce volume, weight, and cost, and to greatly improve system reliability. RF and IF matrix switch technology based on GaAs MMIC's is also being developed for these reasons. MMIC technology, including gigabit-rate GaAs digital integrated circuits, offers substantial advantages in power consumption and weight over silicon technologies for high-throughput, on-board baseband processor systems. In this paper, current developments in GaAs MMIC technology are described, and the status and prospects of the technology are assessed.

  11. Microwave melt and offgas analysis results from a Ferro Corporation reg-sign glass frit

    International Nuclear Information System (INIS)

    Phillips, J.A.; Hoffman, C.R.; Knutson, P.T.

    1995-03-01

    In support of the Residue Treatment Technology (RTT) Microwave Solidification project, Waste Projects and Surface Water personnel conducted a series of experiments to determine the feasibility of encapsulating a surrogate sludge waste using the microwave melter. The surrogate waste was prepared by RTT and melted with five varying compositions of low melting glass frit supplied by the Ferro Corporation. Samples were melted using a 50% waste/50% glass frit and a 47.5% waste/47.5% glass frit/5% carbon powder. This was done to evaluate the effectiveness of carbon at reducing a sulfate-based surface scale which has been observed in previous experiments and in full-scale testing. These vitrified samples were subsequently submitted to Environmental Technology for toxicity characteristic leaching procedure (TCLP) testing. Two of the five frits tested in this experiment merit further evaluation as raw materials for the microwave melter. Ferro frit 3110 with and without carbon powder produced a crystalline product which passed TCLP testing. The quality of the melt product could be improved by increasing the melting temperature from 900 degrees C to approximately 1150-1200 degrees C. Ferro frit 3249 produced the optimal quality of glass based on visual observations, but failed TCLP testing for silver when melted without carbon powder. This frit requires a slightly higher melting temperature (≥ 1200 degrees C) compared to frit 3110 and produces a superior product. In conjunction with this work, Surface Water personnel conducted offgas analyses using a Thermal Desorption Mass Spectrometer (TDMS) on selected formulations. The offgas analyses identified and quantified water vapor (H 2 O), oxygen (O 2 ) and carbon oxides (CO and CO 2 ), sulfur (S) and sulfur oxides (SO and SO 2 ), and nitrogen (N 2 ) and nitrogen oxides (NO and NO 2 ) that volatilized during glass formation

  12. [Application of microwave technology in extraction process of Guizhi Fuling capsule].

    Science.gov (United States)

    Wang, Zheng-kuan; Zhou, Mao; Liu, Yuan; Bi, Yu-an; Wang, Zhen-zhong; Xiao, Wei

    2015-06-01

    In this paper, optimization of the conditions of microwave technique in extraction process of Guizhi Fuling capsule in the condition of a pilot scale was carried out. First of all, through the single factor experiment investigation of various factors, the overall impact tendency and range of each factor were determined. Secondly, L9 (3(4)) orthogonal test optimization was used, and the contents of gallic acid in liquid, paeoniflorin, benzoic acid, cinnamic acid, benzoyl paeoniflorin, amygdalin of the liquid medicine were detected. The extraction rate and comprehensive evaluation were calculated with the extraction effect, as the judgment basis. Theoptimum extraction process of Guizhi Fuling capsule by microwave technology was as follows: the ratio of liquid to solid was 6: 1 added to drinking water, the microwave power was 6 kW, extraction time was 20 min for 3 times. The process of the three batch of amplification through verification, the results are stable, and compared with conventional water extraction has the advantages of energy saving, time saving, high efficiency advantages. The above results show the optimum extracting technology of high efficiency, stable and feasible.

  13. Design of a power amplifier for wireless communications using microstrip technology and Microwave Office

    Directory of Open Access Journals (Sweden)

    Christian Tipantuña

    2015-12-01

    Full Text Available This paper provides a detailed description and all the procedures involved in designing a power amplifier using microstrip technology and the design software Microwave OfficeTM. Specifically, the design is oriented to build an amplifier with central frequency at 14 GHz, but the same fundamentals and principles could be applied in the whole range of radio frequency. For the design, a MESFET transistor and simultaneous input and output matching networks are considered. The values of the parameters and the simulation for every stage are computed and performed using AWR Microwave OfficeTM. At the end of the document, a fully functional circuit layout represented in 2D and 3D is shown with all their complementary elements

  14. NOAA JPSS Microwave Integrated Retrieval System (MIRS) Advanced Technology Microwave Sounder (ATMS) Precipitation and Surface Products from NDE

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains two-dimensional precipitation and surface products from the JPSS Microwave Integrated Retrieval System (MIRS) using sensor data from the...

  15. The Replisome-Coupled E3 Ubiquitin Ligase Rtt101Mms22 Counteracts Mrc1 Function to Tolerate Genotoxic Stress.

    Directory of Open Access Journals (Sweden)

    Raymond Buser

    2016-02-01

    Full Text Available Faithful DNA replication and repair requires the activity of cullin 4-based E3 ubiquitin ligases (CRL4, but the underlying mechanisms remain poorly understood. The budding yeast Cul4 homologue, Rtt101, in complex with the linker Mms1 and the putative substrate adaptor Mms22 promotes progression of replication forks through damaged DNA. Here we characterized the interactome of Mms22 and found that the Rtt101(Mms22 ligase associates with the replisome progression complex during S-phase via the amino-terminal WD40 domain of Ctf4. Moreover, genetic screening for suppressors of the genotoxic sensitivity of rtt101Δ cells identified a cluster of replication proteins, among them a component of the fork protection complex, Mrc1. In contrast to rtt101Δ and mms22Δ cells, mrc1Δ rtt101Δ and mrc1Δ mms22Δ double mutants complete DNA replication upon replication stress by facilitating the repair/restart of stalled replication forks using a Rad52-dependent mechanism. Our results suggest that the Rtt101(Mms22 E3 ligase does not induce Mrc1 degradation, but specifically counteracts Mrc1's replicative function, possibly by modulating its interaction with the CMG (Cdc45-MCM-GINS complex at stalled forks.

  16. Evolution of Monolithic Technology for Wireless Communications: GaN MMIC Power Amplifiers For Microwave Radios

    Directory of Open Access Journals (Sweden)

    Vittorio Camarchia

    2014-09-01

    Full Text Available This paper presents the progress of monolithic technology for microwaveapplication, focusing on gallium nitride technology advances in the realization of integratedpower amplifiers. Three design examples, developed for microwave backhaul radios, areshown. The first design is a 7 GHz Doherty developed with a research foundry, while thesecond and the third are a 7 GHz Doherty and a 7–15 GHz dual-band combined poweramplifiers, both based on a commercial foundry process. The employed architectures, themain design steps and the pros and cons of using gallium nitride technology are highlighted.The measured performance demonstrates the potentialities of the employed technology, andthe progress in the accuracy, reliability and performance of the process.

  17. Novel Direct Steelmaking by Combining Microwave, Electric Arc, and Exothermal Heating Technologies

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Xiaodi Huang; Dr. J. Y. Hwang

    2005-03-28

    Steel is a basic material broadly used by perhaps every industry and individual. It is critical to our nation's economy and national security. Unfortunately, the American steel industry is losing competitiveness in the world steel production field. There is an urgent need to develop the next generation of steelmaking technology for the American steel industry. Direct steelmaking through the combination of microwave, electric arc, and exothermal heating is a revolutionary change from current steelmaking technology. This technology can produce molten steel directly from a shippable agglomerate, consisting of iron oxide fines, powdered coal, and ground limestone. This technology is projected to eliminate many current intermediate steelmaking steps including coking, pellet sintering, blast furnace (BF) ironmaking, and basic oxygen furnace (BOF) steelmaking. This technology has the potential to (a) save up to 45% of the energy consumed by conventional steelmaking; (b) dramatically reduce the emission of CO{sub 2}, SO{sub 2}, NO{sub x}, VOCs, fine particulates, and air toxics; (c) substantially reduce waste and emission control costs; (d) greatly lower capital cost; and (e) considerably reduce steel production costs. This technology is based on the unique capability of microwaves to rapidly heat steelmaking raw materials to elevated temperature, then rapidly reduce iron oxides to metal by volumetric heating. Microwave heating, augmented with electric arc and exothermal reactions, is capable of producing molten steel. This technology has the components necessary to establish the ''future'' domestic steel industry as a technology leader with a strong economically competitive position in world markets. The project goals were to assess the utilization of a new steelmaking technology for its potential to achieve better overall energy efficiency, minimize pollutants and wastes, lower capital and operating costs, and increase the competitiveness of the

  18. A Brief Review on Metamaterial-Based Vacuum Electronics for Terahertz and Microwave Science and Technology

    Science.gov (United States)

    Matsui, Tatsunosuke

    2017-09-01

    Metamaterials, which enable us to realize novel physical effects that cannot be achieved using natural materials, have been extensively studied in recent years and significant progress has been made, especially in the field of optics. This game-changing concept has also initiated a rich variety of research activity in vacuum electronics. Here we review the recent development of metamaterial-based vacuum electronics for terahertz (THz) and microwave science and technology. The reversed Cherenkov radiation (RCR) in double-negative (DNG) metamaterials predicted by Veselago back in the 1960s has been experimentally verified in the microwave frequency range by utilizing specially designed DNG metamaterials. The interaction of an electron beam (e-beam) with DNG metamaterials may lead to the realization of novel applications such as microwave and THz radiation sources, accelerators, and even the visualization of invisibility cloaks. Smith-Purcell radiation (SPR) has recently received renewed interest owing to the development of metamaterials and the concept of spoof surface plasmon polaritons, as discussed in this review, and recent results on e-beam-induced directional and wide-band THz radiation with sharp multiple peaks from a graded grating, as well as directional and monochromatic special SPR and their possible application to THz orotron devices, are also reviewed.

  19. A 3D Model of the Thermoelectric Microwave Power Sensor by MEMS Technology

    Directory of Open Access Journals (Sweden)

    Zhenxiang Yi

    2016-06-01

    Full Text Available In this paper, a novel 3D model is proposed to describe the temperature distribution of the thermoelectric microwave power sensor. In this 3D model, the heat flux density decreases from the upper surface to the lower surface of the GaAs substrate while it was supposed to be a constant in the 2D model. The power sensor is fabricated by a GaAs monolithic microwave integrated circuit (MMIC process and micro-electro-mechanical system (MEMS technology. The microwave performance experiment shows that the S11 is less than −26 dB over the frequency band of 1–10 GHz. The power response experiment demonstrates that the output voltage increases from 0 mV to 27 mV, while the incident power varies from 1 mW to 100 mW. The measured sensitivity is about 0.27 mV/mW, and the calculated result from the 3D model is 0.28 mV/mW. The relative error has been reduced from 7.5% of the 2D model to 3.7% of the 3D model.

  20. An Assessment of Data from the Advanced Technology Microwave Sounder at the Met Office

    Directory of Open Access Journals (Sweden)

    Amy Doherty

    2015-01-01

    Full Text Available An appraisal of the Advanced Technology Microwave Sounder (ATMS for use in numerical weather prediction (NWP is presented, including an assessment of the data quality, the impact on Met Office global forecasts in preoperational trials, and a summary of performance over a period of 17 months operational use. After remapping, the noise performance (NEΔT of the tropospheric temperature sounding channels is evaluated to be approximately 0.1 K, comparing favourably with AMSU-A. However, the noise is not random, differences between observations and simulations based on short-range forecast fields show a spurious striping effect, due to 1/f noise in the receiver. The amplitude of this signal is several tenths of a Kelvin, potentially a concern for NWP applications. In preoperational tests, adding ATMS data to a full Met Office system already exploiting data from four microwave sounders improves southern hemisphere mean sea level pressure forecasts in the 2- to 5-day range by 1-2%. In operational use, where data from five other microwave sounders is assimilated, forecast impact is typically between −0.05 and −0.1 J/kg (3.4% of total mean impact per day over the period 1 April to 31 July 2013. This suggests benefits beyond redundancy, associated with reducing already small analysis errors.

  1. Optical technology for microwave applications VI and optoelectronic signal processing for phased-array antennas III; Proceedings of the Meeting, Orlando, FL, Apr. 20-23, 1992

    Science.gov (United States)

    Yao, Shi-Kay; Hendrickson, Brian M.

    The following topics related to optical technology for microwave applications are discussed: advanced acoustooptic devices, signal processing device technologies, optical signal processor technologies, microwave and optomicrowave devices, advanced lasers and sources, wideband electrooptic modulators, and wideband optical communications. The topics considered in the discussion of optoelectronic signal processing for phased-array antennas include devices, signal processing, and antenna systems.

  2. Novel Low Loss Wide-Band Multi-Port Integrated Circuit Technology for RF/Microwave Applications

    Science.gov (United States)

    Simons, Rainee N.; Goverdhanam, Kavita; Katehi, Linda P. B.; Burke, Thomas P. (Technical Monitor)

    2001-01-01

    In this paper, novel low loss, wide-band coplanar stripline technology for radio frequency (RF)/microwave integrated circuits is demonstrated on high resistivity silicon wafer. In particular, the fabrication process for the deposition of spin-on-glass (SOG) as a dielectric layer, the etching of microvias for the vertical interconnects, the design methodology for the multiport circuits and their measured/simulated characteristics are graphically illustrated. The study shows that circuits with very low loss, large bandwidth, and compact size are feasible using this technology. This multilayer planar technology has potential to significantly enhance RF/microwave IC performance when combined with semi-conductor devices and microelectromechanical systems (MEMS).

  3. New Structure for a Six-Port Reflectometer in Monolithic Microwave Integrated-Circuit Technology

    OpenAIRE

    Wiedmann , Frank; Huyart , Bernard; Bergeault , Eric; Jallet , Louis

    1997-01-01

    International audience; This paper presents a new structure for a six-port reflectometer which due to its simplicity can be implemented very easily in monolithic microwave integrated-circuit (MMIC) technology. It uses nonmatched diode detectors with a high input impedance which are placed around a phase shifter in conjunction with a power divider for the reference detector. The circuit has been fabricated using the F20 GaAs process of the GEC–Marconi foundry and operates between 1.3 GHz and 3...

  4. Wideband Monolithic Microwave Integrated Circuit Frequency Converters with GaAs mHEMT Technology

    OpenAIRE

    Krozer, Viktor; Johansen, Tom Keinicke; Djurhuus, Torsten; Vidkjær, Jens

    2005-01-01

    We present monolithic microwave integrated circuit (MMIC) frequency converter, which can be used for up and down conversion, due to the large RF and IF port bandwidth. The MMIC converters are based on commercially available GaAs mHEMT technology and are comprised of a Gilbert mixer cell core, baluns and combiners. Single ended and balanced configurations DC and AC coupled have been investigated. The instantaneous 3 dB bandwidth at both the RF and the IF port of the frequency converters is ∼ 2...

  5. Microwave heating for thermoplastic composites - Could the technology be used for welding applications?

    Science.gov (United States)

    Barasinski, Anaïs; Tertrais, Hermine; Bechtel, Stéphane; Chinesta, Francisco

    2018-05-01

    Welding primary structure thermoplastic composites parts is still an issue today, many technologies have been extensively studied: induction, ultrasonic, resistive welding, none is today entirely viable for this application due to various implementation reasons. On the other hand, microwave solutions are not very common in composites forming process, although being widespread in homes. Microwave (MW) technology relies on volumetric heating. Thermal energy is transferred from an electromagnetic field to materials that can absorb it at specific frequencies. Volumetric heating enables better process temperature control and less overall energy losses, which can results in shorter processing cycles and higher process efficiency. Nowadays, the main drawback of this technology is that the complex physics involved in the conversion of electromagnetic energy in thermal energy (heating) is not entirely understood and controlled for complex materials. In that work, the authors propose to look deeper in that way, first proposing a simulation tool, based on a coupling between a commercial code and a home made one, allowing the following of the electromagnetic field very precisely in the thickness of a laminate composite part, the last consisting of a stack of layers with different orientations, each layer made of a resin matrix and carbon fibers. Thermal fields are then computed and validated by experimental measurements. In a second part, the authors propose to look at a common welding case of a stringer, on a skin.

  6. RESEARCH OF MICROWAVE DRYING OF NATURAL ZEOLITE GRANULES AND ITS INFLUENCE ON THE TECHNOLOGICAL PROPERTIES

    Directory of Open Access Journals (Sweden)

    Rybachuk V.D.

    2016-06-01

    Full Text Available Introduction. The wet granulation technique is often used in the preparation of free-flowing granules in the manufacture of tablets and capsules. It is very important that granules obtained by this technology be dried before further processing. And also, it is important that the method of drying is entirely controlled and managed and the result is quite predictable. In recent years, microwave drying of granules make a considerable interest. Microwave drying is especially useful for moisture sensitive materials which are mostly pharmaceutical substances. Microwave drying technology is useful for dosage forms with high purity, since this method provides the possibility of drying in the same container production, which reduces the chance of cross contamination of matter and its direct contact with staff. The aim of this work was to study the effect of microwave radiation on the technological properties of natural zeolite peets compared to traditional convection method and to determine the optimal drying modes and specific humidity of the material. Material & methods. Granules were prepared by wet granulation technology by using a laboratory granulator NG-12. As the humidifier we used potato starch gel and PVP in an amount of 25% by weight of the dry product. The resulting granules were divided into two equal parts and subjected to drying in a microwave oven (Delfa D20MW of installed capacity (119 W, 280 W, 336 W, 462 W, ​​595 W and 700 W and shelf dryer to a residual moisture level of 0.01 g.w./g.d.m. or less. Determination of the specific humidity of granules was carried out by mass loss on drying. Fractional composition of granules was determined using a standard set of sieves with the diameter of the holes 2.0; 1.0; 0.5 and 0.25 mm. The friability of the granules was determined using friabilator Pharma Test PTF 10E / ER, Germany. To characterize the fluidity of granule Carr`s indicator (IC and coefficient Hausnera (HR. Results & discussion

  7. Long-distance power transmission technology. Microwave power transmission; Denryoku no chokyori yuso gijutsu. Micro ha musen soden

    Energy Technology Data Exchange (ETDEWEB)

    Kaya, N [Kobe University, Kobe (Japan). Faculty of Engineering

    1994-11-05

    This paper explains the principles of microwave power transmission as a long-distance power transmission technology, and the status of its development. Under an assumption of using a wave length of 12 cm (2.45 GHz) and a transmission distance of 1 km, an ideal wireless power transmission can realize transmitting the power at an efficiency of 95% or higher if transmitting and receiving antennas with a radius of 8.8 m are used. What remains as important requirements is raising the efficiency of conversion from power supply into microwaves, and the efficiency of rectification after the power has been received. By using microwave energy sent from a transmission antenna installed on the roof of an automobile, a model airplane with a receiving antenna installed at its rear flew successfully for 40 seconds under the microwave lifted airplane experiment (MILAX). In an experiment of transmitting microwave power in space, power was successfully transmitted to the child rocket as an event under the International Space Year - Microwave Energy Transmission in Space (ISY-METS). The microwave wireless power transmission on the ground would have a possibility of taking over the overhead line transmission into islands. An attempt is scheduled to send power of 5 kW by using transmission and receiving antennas with a diameter of 3 m to investigate effects on transmission efficiency, and communications and electromagnetic environments, and to collect basic data. 3 refs., 3 figs.

  8. Structural basis for recognition of H3K56-acetylated histone H3-H4 by the chaperone Rtt106

    Energy Technology Data Exchange (ETDEWEB)

    Su, Dan; Hu, Qi; Li, Qing; Thompson, James R; Cui, Gaofeng; Fazly, Ahmed; Davies, Brian A; Botuyan, Maria Victoria; Zhang, Zhiguo; Mer, Georges [Mayo

    2013-04-08

    Dynamic variations in the structure of chromatin influence virtually all DNA-related processes in eukaryotes and are controlled in part by post-translational modifications of histones. One such modification, the acetylation of lysine 56 (H3K56ac) in the amino-terminal α-helix (αN) of histone H3, has been implicated in the regulation of nucleosome assembly during DNA replication and repair, and nucleosome disassembly during gene transcription. In Saccharomyces cerevisiae, the histone chaperone Rtt106 contributes to the deposition of newly synthesized H3K56ac-carrying H3-H4 complex on replicating DNA, but it is unclear how Rtt106 binds H3-H4 and specifically recognizes H3K56ac as there is no apparent acetylated lysine reader domain in Rtt106. Here, we show that two domains of Rtt106 are involved in a combinatorial recognition of H3-H4. An N-terminal domain homodimerizes and interacts with H3-H4 independently of acetylation while a double pleckstrin-homology (PH) domain binds the K56-containing region of H3. Affinity is markedly enhanced upon acetylation of K56, an effect that is probably due to increased conformational entropy of the αN helix of H3. Our data support a mode of interaction where the N-terminal homodimeric domain of Rtt106 intercalates between the two H3-H4 components of the (H3-H4)2 tetramer while two double PH domains in the Rtt106 dimer interact with each of the two H3K56ac sites in (H3-H4)2. We show that the Rtt106-(H3-H4)2 interaction is important for gene silencing and the DNA damage response.

  9. Microwave photonics

    CERN Document Server

    Lee, Chi H

    2006-01-01

    Wireless, optical, and electronic networks continue to converge, prompting heavy research into the interface between microwave electronics, ultrafast optics, and photonic technologies. New developments arrive nearly as fast as the photons under investigation, and their commercial impact depends on the ability to stay abreast of new findings, techniques, and technologies. Presenting a broad yet in-depth survey, Microwave Photonics examines the major advances that are affecting new applications in this rapidly expanding field.This book reviews important achievements made in microwave photonics o

  10. Development of the Advanced Technology Microwave Sounder (ATMS) for NPOESS C1

    Science.gov (United States)

    Brann, C.; Kunkee, D.

    2008-12-01

    The National Polar-orbiting Operational Environmental Satellite System's Advanced Technology Microwave Sounder (ATMS) is planned for flight on the first NPOESS mission (C1) in 2013. The C1 ATMS will be the second instrument of the ATMS series and will provide along with the companion Cross-track Infrared Sounder (CrIS), atmospheric temperature and moisture profiles for NPOESS. The first flight of the ATMS is scheduled in 2010 on the NPOESS Preparatory Project (NPP) satellite, which is an early instrument risk reduction component of the NPOESS mission. This poster will focus on the development of the ATMS for C1 including aspects of the sensor calibration, antenna beam and RF characteristics and scanning. New design aspects of the C1 ATMS, required primarily by parts obsolescence, will also be addressed in this poster.

  11. Pyrolysis of corn stalk biomass briquettes in a scaled-up microwave technology.

    Science.gov (United States)

    Salema, Arshad Adam; Afzal, Muhammad T; Bennamoun, Lyes

    2017-06-01

    Pyrolysis of corn stalk biomass briquettes was carried out in a developed microwave (MW) reactor supplied with 2.45GHz frequency using 3kW power generator. MW power and biomass loading were the key parameters investigated in this study. Highest bio-oil, biochar, and gas yield of 19.6%, 41.1%, and 54.0% was achieved at different process condition. In terms of quality, biochar exhibited good heating value (32MJ/kg) than bio-oil (2.47MJ/kg). Bio-oil was also characterised chemically using FTIR and GC-MS method. This work may open new dimension towards development of large-scale MW pyrolysis technology. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Microwave Technologies as Part of an Integrated Weed Management Strategy: A Review

    Directory of Open Access Journals (Sweden)

    Graham Brodie

    2012-01-01

    Full Text Available Interest in controlling weed plants using radio frequency or microwave energy has been growing in recent years because of the growing concerns about herbicide resistance and chemical residues in the environment. This paper reviews the prospects of using microwave energy to manage weeds. Microwave energy effectively kills weed plants and their seeds; however, most studies have focused on applying the microwave energy over a sizable area, which requires about ten times the energy that is embodied in conventional chemical treatments to achieve effective weed control. A closer analysis of the microwave heating phenomenon suggests that thermal runaway can reduce microwave weed treatment time by at least one order of magnitude. If thermal runaway can be induced in weed plants, the energy costs associated with microwave weed management would be comparable with chemical weed control.

  13. Microwave energy transmission

    Energy Technology Data Exchange (ETDEWEB)

    Matsumoto, Hiroshi [Kyoto Univ. (Japan)

    1989-03-05

    Laying stress on the technological problems and effect on the environment of microwave energy transmission, recent scientific and engineering problems and related subjects are described. Because no fuel is required for the solar power generation, the power generation system can not be considered as an expensive one when the unit cost of energy is taken into consideration. Some of the important technological problems in the microwave energy transmission are accurate microwave beam control technology to receiving stations and improvement in the efficiency of transmission system. Microwave energy beam has effects on living bodies, communication, and plasma atmosphere of the earth. Microwave energy transmission using a space flyer unit is scheduled. Its objective is the development of microwave wireless transmission technology and the study of the correlation between high power microwave and ionosphere plasma. Experiments on such a small scale application as a microwave driven space ship to bring results seem also important. 12 refs., 13 figs.

  14. Multimodal sensing and imaging technology by integrated scanning electron, force, and nearfield microwave microscopy and its application to submicrometer studies

    OpenAIRE

    Hänßler, Olaf C.

    2018-01-01

    The work covers a multimodal microscope technology for the analysis, manipulation and transfer of materials and objects in the submicrometer range. An atomic force microscope (AFM) allows imaging of the surface topography and a Scanning Microwave Microscope (SMM) detects electromagnetic properties, both operating in a Scanning Electron Microscope (SEM). The described technology demonstrator allows to observe the region-of-interest live with the SEM, while at the same time a characterization w...

  15. RTT-D Guidance: Implementing Performance Metrics for Continuous Improvement That Support the Foundational Conditions for Personalized Learning

    Science.gov (United States)

    Johnson, Jessica; Kendziora, Kimberly; Osher, David

    2012-01-01

    The Race to the Top-District (RTT-D) competition asks districts to personalize education for all students in their schools, focusing on classrooms and the relationship between educators and students. To reach this bold goal, the competition calls for providing teachers with "the information, tools, and supports that enable them to meet the…

  16. A cell-free fluorometric high-throughput screen for inhibitors of Rtt109-catalyzed histone acetylation.

    Directory of Open Access Journals (Sweden)

    Jayme L Dahlin

    Full Text Available The lysine acetyltransferase (KAT Rtt109 forms a complex with Vps75 and catalyzes the acetylation of histone H3 lysine 56 (H3K56ac in the Asf1-H3-H4 complex. Rtt109 and H3K56ac are vital for replication-coupled nucleosome assembly and genotoxic resistance in yeast and pathogenic fungal species such as Candida albicans. Remarkably, sequence homologs of Rtt109 are absent in humans. Therefore, inhibitors of Rtt109 are hypothesized as potential and minimally toxic antifungal agents. Herein, we report the development and optimization of a cell-free fluorometric high-throughput screen (HTS for small-molecule inhibitors of Rtt109-catalyzed histone acetylation. The KAT component of the assay consists of the yeast Rtt109-Vps75 complex, while the histone substrate complex consists of full-length Drosophila histone H3-H4 bound to yeast Asf1. Duplicated assay runs of the LOPAC demonstrated day-to-day and plate-to-plate reproducibility. Approximately 225,000 compounds were assayed in a 384-well plate format with an average Z' factor of 0.71. Based on a 3σ cut-off criterion, 1,587 actives (0.7% were identified in the primary screen. The assay method is capable of identifying previously reported KAT inhibitors such as garcinol. We also observed several prominent active classes of pan-assay interference compounds such as Mannich bases, catechols and p-hydroxyarylsulfonamides. The majority of the primary active compounds showed assay signal interference, though most assay artifacts can be efficiently removed by a series of straightforward counter-screens and orthogonal assays. Post-HTS triage demonstrated a comparatively small number of confirmed actives with IC50 values in the low micromolar range. This assay, which utilizes five label-free proteins involved in H3K56 acetylation in vivo, can in principle identify compounds that inhibit Rtt109-catalyzed H3K56 acetylation via different mechanisms. Compounds discovered via this assay or adaptations thereof could

  17. Electro-Optics Millimeter/Microwave Technology in Japan. Report of DoD Technology Team.

    Science.gov (United States)

    1985-05-01

    sink packages covering frequencies up to 94 GHz is being produced. They are suitable for both con- tinuous wave (CW) and pulsed operations. Mean -time...Processing Tel ecommunications Semiconductor and Electronic Components The Technology Team visited the Fujitsu Laboratory, Kanagawa. Topics covered included...Japan, the representatives of the Government of Japan and the Government of the United States of America have held discussions on the ways and means to

  18. Microwave processing heats up

    Science.gov (United States)

    Microwaves are a common appliance in many households. In the United States microwave heating is the third most popular domestic heating method food foods. Microwave heating is also a commercial food processing technology that has been applied for cooking, drying, and tempering foods. It's use in ...

  19. Modeling and design of a capacitive microwave power sensor for X-band applications based on GaAs technology

    Science.gov (United States)

    Cui, Yan; Liao, Xiaoping

    2012-05-01

    In the work, modeling and design of a capacitive microwave power sensor employing the MEMS plate with clamped-clamped and free-free edges are presented. A novel analytical model of the sensor is established in detail. Through the function of mode shapes presented, the natural frequency can be solved by the Rayleigh-Ritz method. And based on the generalized coordinate introduced, the displacement of the plate with the irradiation of microwave power can be solved. Furthermore, the sensitivity for the power is also derived. Then the detailed consideration of the design and simulation of the microwave characteristic of the sensor are also presented. The linearly graded ground planar in the coplanar waveguide is employed to avoid step discontinuity. The fabrication process is compatible with GaAs MMIC technology completely, also described in detail. The measurement of the proposed sensor indicates a sensitivity of 7.2 fF W-1 and superior return and insertion losses (S11 and S21), less than -22.16 dB and -0.25 dB, respectively, up to 12 GHz, suggesting that it can be available for microwave power detecting in the X-band frequency range.

  20. Modeling and design of a capacitive microwave power sensor for X-band applications based on GaAs technology

    International Nuclear Information System (INIS)

    Cui, Yan; Liao, Xiaoping

    2012-01-01

    In the work, modeling and design of a capacitive microwave power sensor employing the MEMS plate with clamped–clamped and free–free edges are presented. A novel analytical model of the sensor is established in detail. Through the function of mode shapes presented, the natural frequency can be solved by the Rayleigh–Ritz method. And based on the generalized coordinate introduced, the displacement of the plate with the irradiation of microwave power can be solved. Furthermore, the sensitivity for the power is also derived. Then the detailed consideration of the design and simulation of the microwave characteristic of the sensor are also presented. The linearly graded ground planar in the coplanar waveguide is employed to avoid step discontinuity. The fabrication process is compatible with GaAs MMIC technology completely, also described in detail. The measurement of the proposed sensor indicates a sensitivity of 7.2 fF W −1 and superior return and insertion losses (S 11 and S 21 ), less than −22.16 dB and −0.25 dB, respectively, up to 12 GHz, suggesting that it can be available for microwave power detecting in the X-band frequency range. (paper)

  1. Impact of advanced technology microwave sounder data in the NCMRWF 4D-VAR data assimilation system

    Science.gov (United States)

    Rani, S. Indira; Srinivas, D.; Mallick, Swapan; George, John P.

    2016-05-01

    This study demonstrates the added benefits of assimilating the Advanced Technology Microwave Sounder (ATMS) radiances from the Suomi-NPP satellite in the NCMRWF Unified Model (NCUM). ATMS is a cross-track scanning microwave radiometer inherited the legacy of two very successful instrument namely, Advanced Microwave Sounding Unit-A (AMSU-A) and Microwave Humidity Sounder (MHS). ATMS has 22 channels: 11 temperature sounding channels around 50-60 GHz oxygen band and 6 moisture sounding channels around the 183GHz water vapour band in addition to 5 channels sensitive to the surface in clear conditions, or to water vapour, rain, and cloud when conditions are not clear (at 23, 31, 50, 51 and 89 GHz). Before operational assimilation of any new observation by NWP centres it is standard practice to assess data quality with respect to NWP model background (short-forecast) fields. Quality of all channels is estimated against the model background and the biases are computed and compared against that from the similar observations. The impact of the ATMS data on global analyses and forecasts is tested by adding the ATMS data in the NCUM Observation Processing system (OPS) and 4D-Var variational assimilation (VAR) system. This paper also discusses the pre-operational numerical experiments conducted to assess the impact of ATMS radiances in the NCUM assimilation system. It is noted that the performance of ATMS is stable and it contributes to the performance of the model, complimenting observations from other instruments.

  2. Unraveling the mysteries of microwave chemistry using silicon carbide reactor technology.

    Science.gov (United States)

    Kappe, C Oliver

    2013-07-16

    In the past few years, the use of microwave energy to heat chemical reactions has become an increasingly popular theme in the scientific community. This nonclassical heating technique has slowly progressed from a laboratory curiosity to an established method commonly used both in academia and in industry. Because of its efficiency, microwave heating dramatically reduces reaction times (from days and hours to minutes and seconds) and improves product purities or material properties among other advantages. Since the early days of microwave chemistry, researchers have observed rate-accelerations and, in some cases, altered product distributions as compared with reactions carried out using classical oil-bath heating. As a result, researchers have speculated that so-called specific or nonthermal microwave effects could be responsible for these differences. Much of the debate has centered on the question of whether the electromagnetic field can exert a direct influence on a chemical transformation outside of the simple macroscopic change in bulk reaction temperature. In 2009, our group developed a relatively simple "trick" that allows us to rapidly evaluate whether an observed effect seen in a microwave-assisted reaction results from a purely thermal phenomenon, or involves specific or nonthermal microwave effects. We use a microwave reaction vessel made from silicon carbide (SiC) ceramic. Because of its high microwave absorptivity, the vessel shields its contents from the electromagnetic field. As a result, we can easily mimic a conventionally heated autoclave experiment inside a microwave reactor under carefully controlled reaction conditions. The switch from an almost microwave transparent glass (Pyrex) to a strongly microwave absorbing SiC reaction vial under otherwise identical reaction conditions (temperature profiles, pressure, stirring speed) then allows us to carefully evaluate the influence of the electromagnetic field on the particular chemical transformation

  3. Wormhole Detection Based on Ordinal MDS Using RTT in Wireless Sensor Network

    Directory of Open Access Journals (Sweden)

    Saswati Mukherjee

    2016-01-01

    Full Text Available In wireless communication, wormhole attack is a crucial threat that deteriorates the normal functionality of the network. Invasion of wormholes destroys the network topology completely. However, most of the existing solutions require special hardware or synchronized clock or long processing time to defend against long path wormhole attacks. In this work, we propose a wormhole detection method using range-based topology comparison that exploits the local neighbourhood subgraph. The Round Trip Time (RTT for each node pair is gathered to generate neighbour information. Then, the network is reconstructed by ordinal Multidimensional Scaling (MDS followed by a suspicion phase that enlists the suspected wormholes based on the spatial reconstruction. Iterative computation of MDS helps to visualize the topology changes and can localize the potential wormholes. Finally, a verification phase is used to remove falsely accused nodes and identify real adversaries. The novelty of our algorithm is that it can detect both short path and long path wormhole links. Extensive simulations are executed to demonstrate the efficacy of our approach compared to existing ones.

  4. NOAA JPSS Advanced Technology Microwave Sounder (ATMS)-based Tropical Cyclone (TC) Products from NDE

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The JPSS Microwave Sounder-based Tropical Cyclone (TC) Products provide estimates of tropical cyclone maximum wind speed, minimum sea level pressure, radii of 34,...

  5. Electromagnetic modeling and characterization of an optically-controlled microwave phase shifterin GaAs integrated technology

    OpenAIRE

    Tripon-Canseliet, C.; Faci, S.; Deshours, F.; Algani, C.; Alquié, G.; Formont, S.; Chazelas, J.

    2005-01-01

    A state of the art of the modeling of microwave photoswitching devices is exposed. A new 3 D electromagnetic modeling allows the design of an optically-controlled microwave phase shifter microwave starting from the traditional circuit of a microwave photoswitch. Measurements of the parameters S of this optically-controlled microwave phase shifter attests the function of this circuit by optical way and highlights the interest of the integration of this new type of microwave phase shifters in ...

  6. Microwave frequency detector at X-band using GaAs MMIC technology

    International Nuclear Information System (INIS)

    Zhang Jun; Liao Xiaoping; Jiao Yongchang

    2009-01-01

    The design, fabrication, and experimental results of an MEMS microwave frequency detector are presented for the first time. The structure consists of a microwave power divider, two CPW transmission lines, a microwave power combiner, an MEMS capacitive power sensor and a thermopile. The detector has been designed and fabricated on GaAs substrate using the MMIC process at the X-band successfully. The MEMS capacitive power sensor is used for detecting the high power signal, while the thermopile is used for detecting the low power signal. Signals of 17 and 10 dBm are measured over the X-band. The sensitivity is 0.56 MHz/fF under 17 dBm by the capacitive power sensor, and 6.67 MHz/μV under 10 dBm by the thermopile, respectively. The validity of the presented design has been confirmed by the experiment.

  7. The research of technology and equipment for a microwave denitration process of the uranyl nitrate solution

    International Nuclear Information System (INIS)

    Bao Weimin; Wang Xuejun; Ma Xuquan; Shi Miaoyi; Zhang Zhicheng; Bao Zhu Tian.

    1991-01-01

    In order to improve the present process of converting the plutonium nitrate into oxide powder in the nuclear fuel cycle, a new conversion process for the direct denitration using microwave heating has been developed. Microwave denitration is based on intramolecular polarization of a material in electric field and has no need of a process of heat transfer during microwave heating, so that the whole material can be heated quickly and uniformly. The thermal decomposition reactions of Pu, U, Th and RE nitrate have been analyzed and compared. The uranyl nitrate solution was chosen as imitative plutonium nitrate solution. The performance parameters ε r tanδ of U, Th and RE nitrate and oxide in microwave field were measured. The data obtained show that all of them could absorb microwave energy well and cause heating decomposition reactions. The microwave denitration test unit was designed and made. Denitration tests for rare-earths nitrate and uranyl nitrate solutions were performed. It could be completed in one step that the uranyl nitrate solution was evaporated, dryed and denitrated in a vessel. The denitrated products are a porous lump and easy to scrape off from the denitration vessel. The main forms of the products UO 3 ·0.8H 2 O and U 3 O 8 which have excellent powder properties. The capacity of the denitration unit is 1.3 kg UO 3 /h. According to the experimental results the simplicity, feasibility and good repeatability of the process have been fully proved. The unit operates easily and is adaptable to conversion of nitrate in nuclear fuel cycle. (author)

  8. Towards a 3D modelling of the microwave photo-induced load in CPW technology

    Science.gov (United States)

    Gary, Rene; Arnould, Jean-Daniel; Vilcot, Anne

    2005-09-01

    The optical control study works on both the optical and the microwave behaviours of the plasma photo-induced in the semiconductor enlightened by a laser beam. The presented study is based on the necessity to be able to foresee the microwave response of CPW microwave devices versus different optical powers and different kinds of optical fibers, single-mode or multimode. The optical part has been achieved analytically by solving the diffusion equation of photo-induced carriers using the Hankel transform in 3-Dimensions. The added value of this technique is its precision and fastness. For the electromagnetic part we have chosen to use CST Microwave Studio software, which solves numerically Maxwell's equations with a Finite Integration Technique (FIT). For this aim we have had to model the photo-induced load using the locally changed conductivity directly depending of the excess carriers distribution. In the final paper, the first part will deal with the analytical computation of the photo-induced excess carrier in silicon substrate using the Hankel transform under permanent enlightening. Then the explanation of the model will be based on the need of a 3-Dimension model that may be described in an electromagnetic software. Finally simulation results of simple CPW devices as stub will be compared to measurements. In conclusion, we will show that the model is suitable for designing more complex devices and that it can be simplified in case of low precision needs.

  9. The Development of Si and SiGe Technologies for Microwave and Millimeter-Wave Integrated Circuits

    Science.gov (United States)

    Ponchak, George E.; Alterovitz, Samuel A.; Katehi, Linda P. B.; Bhattacharya, Pallab K.

    1997-01-01

    Historically, microwave technology was developed by military and space agencies from around the world to satisfy their unique radar, communication, and science applications. Throughout this development phase, the sole goal was to improve the performance of the microwave circuits and components comprising the systems. For example, power amplifiers with output powers of several watts over broad bandwidths, low noise amplifiers with noise figures as low as 3 dB at 94 GHz, stable oscillators with low noise characteristics and high output power, and electronically steerable antennas were required. In addition, the reliability of the systems had to be increased because of the high monetary and human cost if a failure occurred. To achieve these goals, industry, academia and the government agencies supporting them chose to develop technologies with the greatest possibility of surpassing the state of the art performance. Thus, Si, which was already widely used for digital circuits but had material characteristics that were perceived to limit its high frequency performance, was bypassed for a progression of devices starting with GaAs Metal Semiconductor Field Effect Transistors (MESFETs) and ending with InP Pseudomorphic High Electron Mobility Transistors (PHEMTs). For each new material or device structure, the electron mobility increased, and therefore, the high frequency characteristics of the device were improved. In addition, ultra small geometry lithographic processes were developed to reduce the gate length to 0.1 pm which further increases the cutoff frequency. The resulting devices had excellent performance through the millimeter-wave spectrum.

  10. Microwave and RF engineering

    CERN Document Server

    Sorrentino, Roberto

    2010-01-01

    An essential text for both students and professionals, combining detailed theory with clear practical guidance This outstanding book explores a large spectrum of topics within microwave and radio frequency (RF) engineering, encompassing electromagnetic theory, microwave circuits and components. It provides thorough descriptions of the most common microwave test instruments and advises on semiconductor device modelling. With examples taken from the authors' own experience, this book also covers:network and signal theory;electronic technology with guided electromagnetic pr

  11. Improved microwave shielding behavior of carbon nanotube-coated PET fabric using plasma technology

    Energy Technology Data Exchange (ETDEWEB)

    Haji, Aminoddin, E-mail: Ahaji@iaubir.ac.ir [Department of Textile Engineering, Birjand Branch, Islamic Azad University, Birjand (Iran, Islamic Republic of); Semnani Rahbar, Ruhollah [Department of Textile and Leather, Faculty of Chemistry and Petrochemical Engineering, Standard Research Institute, Karaj (Iran, Islamic Republic of); Mousavi Shoushtari, Ahmad [Textile Engineering Department, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of)

    2014-08-30

    Four different procedures were conducted to load amine functionalized multiwall carbon nanotube (NH{sub 2}-MWCNT) onto poly (ethylene terephthalate) (PET) fabric surface to obtain a microwave shielding sample. Plasma treated fabric which was subsequently coated with NH{sub 2}-MWCNT in the presence of acrylic acid was chosen as the best sample. Surface changes in the PET fabrics were investigated by X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). Wide-angle X-ray diffraction was used to study the crystalline structure of the PET fabric. The microwave shielding performance of the PET fabrics in term of reflection loss was determined using a network analyzer at X-band (8.2–12.4 GHz). The XPS results revealed that the carbon atomic percentage decreased while the oxygen atomic percentage increased when the fabric was plasma treated and coated with NH{sub 2}-MWCNT. The SEM images showed that the NH{sub 2}-MWCNTs were homogenously dispersed and individually separated in the surface of fabric. Moreover, the structural studies showed that the crystalline region of the fabrics was not affected by NH{sub 2}-MWCNT and plasma treatment. The best microwave absorbing properties were obtained from the plasma treated fabric which was then coated with 10% NH{sub 2}-MWCNT in the presence of acrylic acid. It showed a minimum reflection loss of ∼−18.2 dB about 11 GHz. Proper attachments of NH{sub 2}-MWCNT on the PET fabric surface was explained in the suggested mechanism in which hydrogen bonding and amide linkage are responsible for the achievement of microwave shielding properties with high durability.

  12. Technological advances in (U,Pu)O2 CRO recycling using microwave heating

    International Nuclear Information System (INIS)

    Das, D.K.; Singh, G.; Khot, P.M; Kumar, S.; Mishra, A.K.; Behere, P.G.; Afzal, Mohd; Kumar, Arun

    2014-01-01

    A batch type wet recycling process viz. microwave direct de-nitration and calcination technique (MWDDC) has been developed at Advanced Fuel Fabrication Facility (AFFF), BARC, Tarapur, India. The process was developed for complete and multiple recycling of PFBR clean rejected (U,Pu)O 2 MOX fuel pellets (CRO) up to 30(wt%) of PuO 2 . The complete recycling of CRO containing higher Pu content with conventional dry recycling was difficult to achieve and certain amount of virgin powder is always needed to obtain the required product characteristics. The conditioned co-de-nitrated powder via MWDDC process have more or less similar characteristics to that of virgin powder with respect to particle size, apparent and tap density, surface area. This paper presents an insight into MWDDC process details and recent advancements made for improvement of powder and product characteristics. Low temperature microwave calcination (LTMC) was incorporated to improve the quality of co-de-nitrated powder with regard to volatile impurities and nitrate content. MWDDC powder and pellets were subjected to extensive chemical and physical characterization as per PFBR specification document. MOX pellets were fabricated from virgin and MWDDC powder via powder oxide pelletizing route and characterized. The homogeneity in the MOX pellets fabricated from MWDDC powder was found as good as that of virgin. Industrial microwave heating systems are indigenously developed and have advanced applicator and wave transmission designs to achieve high throughput, precise control of microwave power hence the temperature during the course of the process. It was demonstrated that MWDDC is a novel technique for (U,Pu)O 2 MOX rejects recycling in view of complete and multiple recycling. Key words: (U,Pu)O 2 MOX, CRO, Recycling, MWDDC. (authors)

  13. Improved microwave shielding behavior of carbon nanotube-coated PET fabric using plasma technology

    International Nuclear Information System (INIS)

    Haji, Aminoddin; Semnani Rahbar, Ruhollah; Mousavi Shoushtari, Ahmad

    2014-01-01

    Four different procedures were conducted to load amine functionalized multiwall carbon nanotube (NH 2 -MWCNT) onto poly (ethylene terephthalate) (PET) fabric surface to obtain a microwave shielding sample. Plasma treated fabric which was subsequently coated with NH 2 -MWCNT in the presence of acrylic acid was chosen as the best sample. Surface changes in the PET fabrics were investigated by X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). Wide-angle X-ray diffraction was used to study the crystalline structure of the PET fabric. The microwave shielding performance of the PET fabrics in term of reflection loss was determined using a network analyzer at X-band (8.2–12.4 GHz). The XPS results revealed that the carbon atomic percentage decreased while the oxygen atomic percentage increased when the fabric was plasma treated and coated with NH 2 -MWCNT. The SEM images showed that the NH 2 -MWCNTs were homogenously dispersed and individually separated in the surface of fabric. Moreover, the structural studies showed that the crystalline region of the fabrics was not affected by NH 2 -MWCNT and plasma treatment. The best microwave absorbing properties were obtained from the plasma treated fabric which was then coated with 10% NH 2 -MWCNT in the presence of acrylic acid. It showed a minimum reflection loss of ∼−18.2 dB about 11 GHz. Proper attachments of NH 2 -MWCNT on the PET fabric surface was explained in the suggested mechanism in which hydrogen bonding and amide linkage are responsible for the achievement of microwave shielding properties with high durability

  14. Functionalization of biochar derived from lignocellulosic biomass using microwave technology for catalytic application in biodiesel production

    International Nuclear Information System (INIS)

    González, M.E.; Cea, M.; Reyes, D.; Romero-Hermoso, L.; Hidalgo, P.; Meier, S.; Benito, N.; Navia, R.

    2017-01-01

    Highlights: • Biochar-based catalyst synthesis was feasible using microwave assistance (MW). • MW transesterification and esterification of waste cooking oil (WCO) was feasible. • The methyl ester yield can reach 75% in 15 min using the functionalized biochar. • WCO conversion via MW in successive cycles is feasible when the catalyst is washed. - Abstract: A study to produce an efficient catalyst to be used for biodiesel production was carried out introducing sulfonic groups in biochar using a microwave reactor. The transesterification reaction of waste cooking oils using the catalyst was also evaluated in a microwave reactor. The results showed that an increase in the temperature up to 140 °C during biochar sulfonation enhanced the SO 3 H content on the catalyst surface. These results were confirmed through FT-IR and XPS analyses. A reduction in the surface area of the biochar was observed during the sulfonation. An increase of SO 3 H groups on the biochar surface was responsible for a higher FAME yield close to 90%. The catalyst could be re-used for up to six cycles by washing with hexane.

  15. Microwave. Instructor's Edition. Louisiana Vocational-Technical Education.

    Science.gov (United States)

    Blanton, William

    This publication contains related study assignments and job sheets for a course in microwave technology. The course is organized into 12 units covering the following topics: introduction to microwave, microwave systems, microwave oscillators, microwave modulators, microwave transmission lines, transmission lines, detectors and mixers, microwave…

  16. Integrated microwave photonics

    NARCIS (Netherlands)

    Marpaung, D.A.I.; Roeloffzen, C.G.H.; Heideman, Rene; Leinse, Arne; Sales, S.; Capmany, J.

    2013-01-01

    Microwave photonics (MWP) is an emerging field in which radio frequency (RF) signals are generated, distributed, processed and analyzed using the strength of photonic techniques. It is a technology that enables various functionalities which are not feasible to achieve only in the microwave domain. A

  17. The microwave market

    International Nuclear Information System (INIS)

    Bybokas, J.

    1989-01-01

    As superconductors move from the laboratory to the marketplace, it becomes more important for researchers and manufacturers to understand the markets for this technology. The large market for microwave systems represents a major opportunity for high-T c superconductors. Conductor losses are a primary design limitation in conventional microwave systems. The low losses of superconductors at microwave frequencies will allow component designers and system designers to improve their products in many ways. The most important market segments for microwave systems are outlined in this discussion

  18. Summary of Recent Results from NASA's Space Solar Power (SSP) Programs and the Current Capabilities of Microwave WPT Technology

    Science.gov (United States)

    McSpadden, James; Mankins, John C.; Howell, Joe T. (Technical Monitor)

    2002-01-01

    The concept of placing enormous solar power satellite (SPS) systems in space represents one of a handful of new technological options that might provide large-scale, environmentally clean base load power into terrestrial markets. In the US, the SPS concept was examined extensively during the late 1970s by the U.S. Department of Energy (DOE) and the National Aeronautics and Space Administration (NASA). More recently, the subject of space solar power (SSP) was reexamined by NASA from 1995-1997 in the "fresh look" study, and during 1998 in an SSP "concept definition study". As a result of these efforts, in 1999-2000, NASA undertook the SSP Exploratory Research and Technology (SERT) program which pursued preliminary strategic technology research and development to enable large, multi-megawatt SSP systems and wireless power transmission (WPT) for government missions and commercial markets (in-space and terrestrial). During 2001-2002, NASA has been pursuing an SSP Concept and Technology Maturation (SCTM) program follow-on to the SERT, with special emphasis on identifying new, high-leverage technologies that might advanced the feasibility of future SSP systems. In addition, in 2001, the U.S. National Research Council (NRC) released a major report providing the results of a peer review of NASA's SSP strategic research and technology (R&T) road maps. One of the key technologies needed to enable the future feasibility of SSP/SPS is that of wireless power transmission. Advances in phased array antennas and rectennas have provided the building blocks for a realizable WPT system. These key components include the dc-RF converters in the transmitter, the retrodirective beam control system, and the receiving rectenna. Each subject is briefly covered, and results from the SERT program that studied a 5.8 GHz SPS system are presented. This paper presents a summary results from NASA's SSP efforts, along with a summary of the status of microwave WPT technology development.

  19. Microwave Ovens

    Science.gov (United States)

    ... Products and Procedures Home, Business, and Entertainment Products Microwave Ovens Share Tweet Linkedin Pin it More sharing ... 1030.10 - Microwave Ovens Required Reports for the Microwave Oven Manufacturers or Industry Exemption from Certain Reporting ...

  20. Microwave engineering

    CERN Document Server

    Pozar, David M

    2012-01-01

    The 4th edition of this classic text provides a thorough coverage of RF and microwave engineering concepts, starting from fundamental principles of electrical engineering, with applications to microwave circuits and devices of practical importance.  Coverage includes microwave network analysis, impedance matching, directional couplers and hybrids, microwave filters, ferrite devices, noise, nonlinear effects, and the design of microwave oscillators, amplifiers, and mixers. Material on microwave and RF systems includes wireless communications, radar, radiometry, and radiation hazards. A large

  1. High power pulsed/microwave technologies for electron accelerators vis a vis 10MeV, 10kW electron LINAC for food irradiation at CAT

    International Nuclear Information System (INIS)

    Shrivastava, Purushottam; Mulchandani, J.; Mohania, P.; Baxy, D.; Wanmode, Y.; Hannurkar, P.R.

    2005-01-01

    Use of electron accelerators for irradiation of food items is gathering momentum in India. The various technologies for powering the electron LINAC were needed to be developed in the country due to embargo situations as well as reservations of the developers worldwide to share the information related to this development. Centre for Advanced Technology, CAT, Indore, is engaged in the development of particle accelerators for medical industrial and scientific applications. Amongst other electron accelerators developed in CAT, a 10MeV, 10kW LINAC for irradiation of food items has been commissioned and tested for full rated 10kW beam power. The high power pulsed microwave driver for the LINAC was designed, developed and commissioned with full indigenous efforts, and is right now operational at CAT. It consists of a 6MW, 25kW S-band pulsed klystron, 15MW peak power pulse modulator system for the klystron, microwave driver amplifier chain, stabilized generator, protection and control electronics, waveguide system to handle the high peak and average power, gun modulator electronics, grid electronics etc. The present paper highlights various technologies like the pulsed power systems and components, microwave circuits and systems etc. Also the performance results of the high power microwave driver for the 10MeV LINAC at CAT are discussed. Future strategies for developing the state of art technologies are highlighted. (author)

  2. Application of microwave sensor technology in cardiovascular disease for plaque detection

    Directory of Open Access Journals (Sweden)

    Wagner David

    2016-09-01

    Full Text Available Arteriosclerosis and associated cardiovascular disease remains the leading cause of mortality. Improved methods for vascular plaque detection allow early diagnose and better therapeutic options. Present diagnostic tools require intense technical expenditure and diminish value of modern screening methods. Our group developed an microwave sensor for on-site detection of plaque formation in arterial vessels. The sensor is an oscillator working around 27 GHz which is coupled to a microstrip stub line. The final flexible polyimid interposer has a length of 38 cm, a width of 1.2 mm and a thickness of 200 μm. Because of its minimal size the interposer completed a catheter with a diameter of 8F ready for further clinical use in cardiology and heart surgery.

  3. Integrated Microwave Photonics

    OpenAIRE

    Marpaung, David; Roeloffzen, Chris; Heideman, René; Leinse, Arne; Sales Maicas, Salvador; Capmany Francoy, José

    2013-01-01

    Microwave photonics (MWP) is an emerging field in which radio frequency (RF) signals are generated, distributed, processed and analyzed using the strength of photonic techniques. It is a technology that enables various functionalities which are not feasible to achieve only in the microwave domain. A particular aspect that recently gains significant interests is the use of photonic integrated circuit (PIC) technology in the MWP field for enhanced functionalities and robustness as well as the r...

  4. Rtt109-dependent histone H3 K56 acetylation and gene activity are essential for the biological control potential of Beauveria bassiana.

    Science.gov (United States)

    Cai, Qing; Wang, Juan-Juan; Shao, Wei; Ying, Sheng-Hua; Feng, Ming-Guang

    2018-04-27

    Rtt109 is a histone acetyltransferase that catalyzes histone H3K56 acetylation required for genomic stability, DNA damage repair and virulence-related gene activity in yeast-like human pathogens but remains functionally unknown in fungal insect pathogens. This study seeks to elucidate catalytic activity of Rtt109 orthologue and its possible role in sustaining biological control potential of Beauveria bassiana, a fungal entomopathogen. Deletion of rtt109 in B. bassiana abolished histone H3K56 acetylation and triggered histone H2A-S129 phosphorylation. Consequently, the deletion mutant showed increased sensitivities to the stresses of DNA damage, oxidation, cell wall perturbation, high osmolarity and heat shock during colony growth, severe conidiation defects under normal culture conditions, reduced conidial hydrophobicity, decreased conidial UV-B resistance, and attenuated virulence through normal cuticle infection. These phenotypic changes correlated well with reduced transcript levels of many genes, which encode the families of H2A-S129 dephosphorylation-related protein phosphotases, DNA damage-repairing factors, antioxidant enzymes, heat-shock proteins, key developmental activators, hydrophobins and cuticle-degrading Pr1 proteases respectively. Rtt109 can acetylate H3K56 and dephosphorylate H2A-S129 in direct and indirect manners respectively, and hence plays an essential role in sustaining genomic stability and global gene activity required for conidiation capacity, environmental fitness and pest-control potential in B. bassiana. This article is protected by copyright. All rights reserved.

  5. Microwave imaging

    CERN Document Server

    Pastorino, Matteo

    2010-01-01

    An introduction to the most relevant theoretical and algorithmic aspects of modern microwave imaging approaches Microwave imaging-a technique used in sensing a given scene by means of interrogating microwaves-has recently proven its usefulness in providing excellent diagnostic capabilities in several areas, including civil and industrial engineering, nondestructive testing and evaluation, geophysical prospecting, and biomedical engineering. Microwave Imaging offers comprehensive descriptions of the most important techniques so far proposed for short-range microwave imaging-in

  6. Precision Membrane Optical Shell (PMOS) Technology for RF/Microwave to Lightweight LIDAR Apertures, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Membrane Optical Shell Technology (MOST) is an innovative combination of 1) very low areal density (40 to 200g/m2) optically smooth (<20 nm rms), metallic coated...

  7. Influence of the microwave technology on solid dispersions of mefenamic acid and flufenamic acid.

    Directory of Open Access Journals (Sweden)

    Sultan Alshehri

    Full Text Available The present studies were undertaken to develop solvent-free solid dispersions (SDs for poorly soluble anti-inflammatory drugs mefenamic acid (MA and flufenamic acid (FFA in order to enhance their in vitro dissolution rate and in vivo anti-inflammatory effects. The SDs of MA and FFA were prepared using microwaves irradiation (MW technique. Different carriers such as Pluronic F127® (PL, Eudragit EPO® (EPO, polyethylene glycol 4000 (PEG 4000 and Gelucire 50/13 (GLU were used for the preparation of SDs. Prepared MW irradiated SDs were characterized physicochemically using differential scanning calorimetry (DSC, thermogravimetric analysis (TGA, Fourier transform infra-red (FT-IR spectroscopy, powder X-ray diffraction (PXRD and scanning electron microscopy (SEM. The physicochemical characteristics and drug release profile of SDs were compared with pure drugs. The results of DSC, TGA, FT-IR, PXRD and SEM showed that SDs were successfully prepared. In vitro dissolution rate of MA and FFA was remarkably enhanced by SDs in comparison with pure MA and FFA. The SDs of MA and FFA prepared using PEG 400 showed higher drug release profile in comparison with those prepared using PL, EPO or GLU. The dissolution efficiency for MA-PEG SD and FFA-PEG SD was obtained as 61.40 and 59.18%, respectively. Optimized SDs were also evaluated for in vivo anti-inflammatory effects in male Wistar rats. The results showed significant % inhibition by MA-PEG (87.74% after 4 h and FFA-PEG SDs (81.76% after 4 h in comparison with pure MA (68.09% after 4 h and pure FFA (55.27% after 4 h (P<0.05. These results suggested that MW irradiated SDs of MA and FFA could be successfully used for the enhancement of in vitro dissolution rate and in vivo therapeutic efficacy of both drugs.

  8. A pilot-scale microwave technology for sludge sanitization and drying

    NARCIS (Netherlands)

    Mawioo, P.M.; Garcia, Hector A.; Hooijmans, Christine M.; Velkushanova, Konstantina; Simonič, Marjana; Mijatović, Ivan; Brdanovic, Damir

    2017-01-01

    Large volumes of sludge are produced from onsite sanitation systems in densely populated areas (e.g. slums and emergency settlements) and wastewater treatment facilities that contain high amounts of pathogens. There is a need for technological options which can effectively treat the rapidly

  9. Results of the activities of the Scientific and Technical Coordination Council for Radiation Technique and Technology

    Energy Technology Data Exchange (ETDEWEB)

    Sille, A K [Gosudarstvennyj Komitet po Ispol' zovaniyu Atomnoj Ehnergii SSSR, Moscow

    1977-03-01

    It is reported on the activities of the Scientific and Technical Coordination Council for Radiation Technique and Technology (STCC-RTT) of the CMEA Permanent Commission for the Peaceful Uses of Atomic Energy according to the programme 1971 to 1975. The STCC-RTT is concerned with technical applications such as radiation sterilization, food irradiation, radiation-induced chemical processes etc. The main tasks which have to be solved within the period from 1976 to 1980 are outlined.

  10. Kub5-Hera, the human Rtt103 homolog, plays dual functional roles in transcription termination and DNA repair.

    Science.gov (United States)

    Morales, Julio C; Richard, Patricia; Rommel, Amy; Fattah, Farjana J; Motea, Edward A; Patidar, Praveen L; Xiao, Ling; Leskov, Konstantin; Wu, Shwu-Yuan; Hittelman, Walter N; Chiang, Cheng-Ming; Manley, James L; Boothman, David A

    2014-04-01

    Functions of Kub5-Hera (In Greek Mythology Hera controlled Artemis) (K-H), the human homolog of the yeast transcription termination factor Rtt103, remain undefined. Here, we show that K-H has functions in both transcription termination and DNA double-strand break (DSB) repair. K-H forms distinct protein complexes with factors that repair DSBs (e.g. Ku70, Ku86, Artemis) and terminate transcription (e.g. RNA polymerase II). K-H loss resulted in increased basal R-loop levels, DSBs, activated DNA-damage responses and enhanced genomic instability. Significantly lowered Artemis protein levels were detected in K-H knockdown cells, which were restored with specific K-H cDNA re-expression. K-H deficient cells were hypersensitive to cytotoxic agents that induce DSBs, unable to reseal complex DSB ends, and showed significantly delayed γ-H2AX and 53BP1 repair-related foci regression. Artemis re-expression in K-H-deficient cells restored DNA-repair function and resistance to DSB-inducing agents. However, R loops persisted consistent with dual roles of K-H in transcription termination and DSB repair.

  11. Dbf4-dependent kinase and the Rtt107 scaffold promote Mus81-Mms4 resolvase activation during mitosis.

    Science.gov (United States)

    Princz, Lissa N; Wild, Philipp; Bittmann, Julia; Aguado, F Javier; Blanco, Miguel G; Matos, Joao; Pfander, Boris

    2017-03-01

    DNA repair by homologous recombination is under stringent cell cycle control. This includes the last step of the reaction, disentanglement of DNA joint molecules (JMs). Previous work has established that JM resolving nucleases are activated specifically at the onset of mitosis. In case of budding yeast Mus81-Mms4, this cell cycle stage-specific activation is known to depend on phosphorylation by CDK and Cdc5 kinases. Here, we show that a third cell cycle kinase, Cdc7-Dbf4 (DDK), targets Mus81-Mms4 in conjunction with Cdc5-both kinases bind to as well as phosphorylate Mus81-Mms4 in an interdependent manner. Moreover, DDK-mediated phosphorylation of Mms4 is strictly required for Mus81 activation in mitosis, establishing DDK as a novel regulator of homologous recombination. The scaffold protein Rtt107, which binds the Mus81-Mms4 complex, interacts with Cdc7 and thereby targets DDK and Cdc5 to the complex enabling full Mus81 activation. Therefore, Mus81 activation in mitosis involves at least three cell cycle kinases, CDK, Cdc5 and DDK Furthermore, tethering of the kinases in a stable complex with Mus81 is critical for efficient JM resolution. © 2017 The Authors. Published under the terms of the CC BY NC ND 4.0 license.

  12. A capacitive membrane MEMS microwave power sensor in the X-band based on GaAs MMIC technology

    International Nuclear Information System (INIS)

    Su Shi; Liao Xiaoping

    2009-01-01

    This paper presents the modeling, fabrication, and measurement of a capacitive membrane MEMS microwave power sensor. The sensor measures microwave power coupled from coplanar waveguide (CPW) transmission lines by a MEMS membrane and then converts it into a DC voltage output by using thermopiles. Since the fabrication process is fully compatible with the GaAs monolithic microwave integrated circuit (MMIC) process, this sensor could be conveniently embedded into MMIC. From the measured DC voltage output and S-parameters, the average sensitivity in the X-band is 225.43 μV/mW, while the reflection loss is below -14 dB. The MEMS microwave power sensor has good linearity with a voltage standing wave ration of less than 1.513 in the whole X-band. In addition, the measurements using amplitude modulation signals prove that the modulation index directly influences the output DC voltage.

  13. Microwave undulator

    International Nuclear Information System (INIS)

    Batchelor, K.

    1986-03-01

    The theory of a microwave undulator utilizing a plane rectangular waveguide operating in the TE/sub 10n/ mode and other higher order modes is presented. Based on this, a possible undulator configuration is analyzed, leading to the conclusion that the microwave undulator represents a viable option for undulator wavelength down to about 1 cm where peak voltage and available microwave power considerations limit effectiveness. 4 refs., 4 figs

  14. Microwave Microscope

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: Makes ultra-high-resolution field measurements. The Microwave Microscope (MWM) has been used in support of several NRL experimental programs involving sea...

  15. Experimental Demonstration of Coexistence of Microwave Wireless Communication and Power Transfer Technologies for Battery-Free Sensor Network Systems

    Directory of Open Access Journals (Sweden)

    Satoshi Yoshida

    2013-01-01

    Full Text Available This paper describes experimental demonstrations of a wireless power transfer system equipped with a microwave band communication function. Battery charging using the system is described to evaluate the possibility of the coexistence of both wireless power transfer and communication functions in the C-band. A battery-free wireless sensor network system is demonstrated, and a high-power rectifier for the system is also designed and evaluated in the S-band. We have confirmed that microwave wireless power transfer can coexist with communication function.

  16. Recent Advancements in Microwave Imaging Plasma Diagnostics

    International Nuclear Information System (INIS)

    Park, H.; Chang, C.C.; Deng, B.H.; Domier, C.W.; Donni, A.J.H.; Kawahata, K.; Liang, C.; Liang, X.P.; Lu, H.J.; Luhmann, N.C. Jr.; Mase, A.; Matsuura, H.; Mazzucato, E.; Miura, A.; Mizuno, K.; Munsat, T.; Nagayama, K.; Nagayama, Y.; Pol, M.J. van de; Wang, J.; Xia, Z.G.; Zhang, W-K.

    2002-01-01

    Significant advances in microwave and millimeter wave technology over the past decade have enabled the development of a new generation of imaging diagnostics for current and envisioned magnetic fusion devices. Prominent among these are revolutionary microwave electron cyclotron emission imaging (ECEI), microwave phase imaging interferometers, imaging microwave scattering and microwave imaging reflectometer (MIR) systems for imaging electron temperature and electron density fluctuations (both turbulent and coherent) and profiles (including transport barriers) on toroidal devices such as tokamaks, spherical tori, and stellarators. The diagnostic technology is reviewed, and typical diagnostic systems are analyzed. Representative experimental results obtained with these novel diagnostic systems are also presented

  17. Microwave solidification development for Rocky Flats waste

    Energy Technology Data Exchange (ETDEWEB)

    Dixon, D.; Erle, R.; Eschen, V. [and others

    1994-04-01

    The Microwave Engineering Team at the Rocky Flats Plant has developed a production-scale system for the treatment of hazardous, radioactive, and mixed wastes using microwave energy. The system produces a vitreous final form which meets the acceptance criteria for shipment and disposal. The technology also has potential for application on various other waste streams from the public and private sectors. Technology transfer opportunities are being identified and pursued for commercialization of the microwave solidification technology.

  18. Microwave solidification development for Rocky Flats waste

    International Nuclear Information System (INIS)

    Dixon, D.; Erle, R.; Eschen, V.

    1994-04-01

    The Microwave Engineering Team at the Rocky Flats Plant has developed a production-scale system for the treatment of hazardous, radioactive, and mixed wastes using microwave energy. The system produces a vitreous final form which meets the acceptance criteria for shipment and disposal. The technology also has potential for application on various other waste streams from the public and private sectors. Technology transfer opportunities are being identified and pursued for commercialization of the microwave solidification technology

  19. Removal of Persistent Organic Pollutants from a Solid Matrix by Thermal Desorption Technology Using Conventional and Microwave Heating

    Czech Academy of Sciences Publication Activity Database

    Mašín, P.; Hendrych, J.; Kroužek, J.; Kubal, M.; Kochánková, L.; Sobek, Jiří

    2013-01-01

    Roč. 22, č. 7A (2013), s. 2017-2021 ISSN 1018-4619. [International Conference on Environmental Management , Engineering, Planning and Economics (CEMEPE 2011) & SECOTOX Conference /3./. Skiathos Island, 19.06.2011-24.06.2011] Grant - others:GA MŽP(CZ) SP/2f3/133/08 Institutional support: RVO:67985858 Keywords : thermal desorption * microwave heating * remediation * persistent pollutants * pilot scale Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 0.527, year: 2013

  20. Microwave Measurements

    CERN Document Server

    Skinner, A D

    2007-01-01

    The IET has organised training courses on microwave measurements since 1983, at which experts have lectured on modern developments. Their lecture notes were first published in book form in 1985 and then again in 1989, and they have proved popular for many years with a readership beyond those who attended the courses. The purpose of this third edition of the lecture notes is to bring the latest techniques in microwave measurements to this wider audience. The book begins with a survey of the theory of current microwave circuits and continues with a description of the techniques for the measureme

  1. Microwave Tokamak Experiment

    International Nuclear Information System (INIS)

    Anon.

    1988-01-01

    The Microwave Tokamak Experiment, now under construction at the Laboratory, will use microwave heating from a free-electron laser. The intense microwave pulses will be injected into the tokamak to realize several goals, including a demonstration of the effects of localized heat deposition within magnetically confined plasma, a better understanding of energy confinement in tokamaks, and use of the new free-electron laser technology for plasma heating. The experiment, soon to be operational, provides an opportunity to study dense plasmas heated by powers unprecedented in the electron-cyclotron frequency range required by the especially high magnetic fields used with the MTX and needed for reactors. 1 references, 5 figures, 3 tables

  2. Balanced microwave filters

    CERN Document Server

    Hong, Jiasheng; Medina, Francisco; Martiacuten, Ferran

    2018-01-01

    This book presents and discusses strategies for the design and implementation of common-mode suppressed balanced microwave filters, including, narrowband, wideband, and ultra-wideband filters This book examines differential-mode, or balanced, microwave filters by discussing several implementations of practical realizations of these passive components. Topics covered include selective mode suppression, designs based on distributed and semi-lumped approaches, multilayer technologies, defect ground structures, coupled resonators, metamaterials, interference techniques, and substrate integrated waveguides, among others. Divided into five parts, Balanced Microwave Filters begins with an introduction that presents the fundamentals of balanced lines, circuits, and networks. Part 2 covers balanced transmission lines with common-mode noise suppression, including several types of common-mode filters and the application of such filters to enhance common-mode suppression in balanced bandpass filters. Next, Part 3 exa...

  3. Performance of a novel microwave-based treatment technology for atrazine removal and destruction: Sorbent reusability and chemical stability, and effect of water matrices

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Erdan; Hu, Yuanan [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Cheng, Hefa, E-mail: hefac@umich.edu [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); MOE Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871 (China)

    2015-12-15

    Highlights: • Cu{sup 2+} and Fe{sup 3+} in zeolite pores enhance atrazine sorption and MW-induced degradation. • Exchanged zeolites perform well over multiple sorption–regeneration cycles. • Fe{sup 3+} species in the zeolite micropores have much greater stability than those of Cu{sup 2+}. • DOC in natural waters can compromise the sorption capacity of exchanged zeolites. • Iron-exchanged dealuminated Y zeolites hold great promise for practical applications. - Abstract: Transition metal-exchanged dealuminated Y zeolites were used to adsorb atrazine from aqueous solutions, followed by regeneration of the sorbents and destruction of the sorbed atrazine with microwave irradiation. Exchange of copper and iron into the zeolite's micropores significantly enhanced its sorption capacity and selectivity toward atrazine, and increased the microwave-induced degradation rate of the sorbed atrazine by 3–4-folds. Both the copper- and iron-exchanged zeolites could be regenerated and reused multiple times, while the catalytic activity of the latter was more robust due to the much greater chemical stability of Fe{sup 3+} species in the micropores. The presence of humic acid, and common cations and anions had little impact on the sorption of atrazine on the transition metal-exchanged zeolites. In the treatment of atrazine spiked in natural surface water and groundwater samples, sorptive removal of atrazine was found to be impacted by the level of dissolved organic carbon, probably through competition for the micropore spaces and pore blocking, while the water matrices exhibited no strong effect on the microwave-induced degradation of sorbed atrazine. Overall, iron-exchanged dealuminated Y zeolites show great potential for removal and destruction of atrazine from contaminated surface water and groundwater in practical implementation of the novel treatment technology.

  4. Performance of a novel microwave-based treatment technology for atrazine removal and destruction: Sorbent reusability and chemical stability, and effect of water matrices

    International Nuclear Information System (INIS)

    Hu, Erdan; Hu, Yuanan; Cheng, Hefa

    2015-01-01

    Highlights: • Cu"2"+ and Fe"3"+ in zeolite pores enhance atrazine sorption and MW-induced degradation. • Exchanged zeolites perform well over multiple sorption–regeneration cycles. • Fe"3"+ species in the zeolite micropores have much greater stability than those of Cu"2"+. • DOC in natural waters can compromise the sorption capacity of exchanged zeolites. • Iron-exchanged dealuminated Y zeolites hold great promise for practical applications. - Abstract: Transition metal-exchanged dealuminated Y zeolites were used to adsorb atrazine from aqueous solutions, followed by regeneration of the sorbents and destruction of the sorbed atrazine with microwave irradiation. Exchange of copper and iron into the zeolite's micropores significantly enhanced its sorption capacity and selectivity toward atrazine, and increased the microwave-induced degradation rate of the sorbed atrazine by 3–4-folds. Both the copper- and iron-exchanged zeolites could be regenerated and reused multiple times, while the catalytic activity of the latter was more robust due to the much greater chemical stability of Fe"3"+ species in the micropores. The presence of humic acid, and common cations and anions had little impact on the sorption of atrazine on the transition metal-exchanged zeolites. In the treatment of atrazine spiked in natural surface water and groundwater samples, sorptive removal of atrazine was found to be impacted by the level of dissolved organic carbon, probably through competition for the micropore spaces and pore blocking, while the water matrices exhibited no strong effect on the microwave-induced degradation of sorbed atrazine. Overall, iron-exchanged dealuminated Y zeolites show great potential for removal and destruction of atrazine from contaminated surface water and groundwater in practical implementation of the novel treatment technology.

  5. Passive Microwave Components and Antennas

    DEFF Research Database (Denmark)

    State-of-the-art microwave systems always require higher performance and lower cost microwave components. Constantly growing demands and performance requirements of industrial and scientific applications often make employing traditionally designed components impractical. For that reason, the design...... and development process remains a great challenge today. This problem motivated intensive research efforts in microwave design and technology, which is responsible for a great number of recently appeared alternative approaches to analysis and design of microwave components and antennas. This book highlights...... techniques. Modelling and computations in electromagnetics is a quite fast-growing research area. The recent interest in this field is caused by the increased demand for designing complex microwave components, modeling electromagnetic materials, and rapid increase in computational power for calculation...

  6. Loss of MeCP2 in cholinergic neurons causes part of RTT-like phenotypes via α7 receptor in hippocampus.

    Science.gov (United States)

    Zhang, Ying; Cao, Shu-Xia; Sun, Peng; He, Hai-Yang; Yang, Ci-Hang; Chen, Xiao-Juan; Shen, Chen-Jie; Wang, Xiao-Dong; Chen, Zhong; Berg, Darwin K; Duan, Shumin; Li, Xiao-Ming

    2016-06-01

    Mutations in the X-linked MECP2 gene cause Rett syndrome (RTT), an autism spectrum disorder characterized by impaired social interactions, motor abnormalities, cognitive defects and a high risk of epilepsy. Here, we showed that conditional deletion of Mecp2 in cholinergic neurons caused part of RTT-like phenotypes, which could be rescued by re-expressing Mecp2 in the basal forebrain (BF) cholinergic neurons rather than in the caudate putamen of conditional knockout (Chat-Mecp2(-/y)) mice. We found that choline acetyltransferase expression was decreased in the BF and that α7 nicotine acetylcholine receptor signaling was strongly impaired in the hippocampus of Chat-Mecp2(-/y) mice, which is sufficient to produce neuronal hyperexcitation and increase seizure susceptibility. Application of PNU282987 or nicotine in the hippocampus rescued these phenotypes in Chat-Mecp2(-/y) mice. Taken together, our findings suggest that MeCP2 is critical for normal function of cholinergic neurons and dysfunction of cholinergic neurons can contribute to numerous neuropsychiatric phenotypes.

  7. Microwave processing of ceramic oxide filaments

    Energy Technology Data Exchange (ETDEWEB)

    Vogt, G.J.; Katz, J.D. [Los Alamos National Laboratory, NM (United States)

    1995-05-01

    The objective of the microwave filament processing project is to develop microwave techniques at 2.45 GHZ to manufacture continuous ceramic oxide filaments. Microwave processing uses the volumetric absorption of microwave power in oxide filament tows to drive off process solvents, to burn out organic binders, and to sinter the dried fibers to produce flexible, high-strength ceramic filaments. The technical goal is to advance filament processing technology by microwave heating more rapidly with less energy and at a lower cost than conventional processing, but with the same quality as conventional processing. The manufacturing goal is to collaborate with the 3M Company, a US manufacturer of ceramic oxide filaments, to evaluate the technology using a prototype filament system and to transfer the microwave technology to the 3M Company.

  8. Commercial microwave space power

    International Nuclear Information System (INIS)

    Siambis, J.; Gregorwich, W.; Walmsley, S.; Shockey, K.; Chang, K.

    1991-01-01

    This paper reports on central commercial space power, generating power via large scale solar arrays, and distributing power to satellites via docking, tethering or beamed power such as microwave or laser beams, that is being investigated as a potentially advantageous alternative to present day technology where each satellite carries its own power generating capability. The cost, size and weight for electrical power service, together with overall mission requirements and flexibility are the principal selection criteria, with the case of standard solar array panels based on the satellite, as the reference point. This paper presents and investigates a current technology design point for beamed microwave commercial space power. The design point requires that 25 kW be delivered to the user load with 30% overall system efficiency. The key elements of the design point are: An efficient rectenna at the user end; a high gain, low beam width, efficient antenna at the central space power station end, a reliable and efficient cw microwave tube. Design trades to optimize the proposed near term design point and to explore characteristics of future systems were performed. Future development for making the beamed microwave space power approach more competitive against docking and tethering are discussed

  9. A Study of the Optical Components of the Hard X-Ray Sources IGR J17544-2619 and IGR J21343+4738 by Using RTT-150 Observations

    Science.gov (United States)

    Nikolaeva, E. A.; Bikmaev, I. F.; Shimansky, V. V.; Sakhibullin, N. A.

    2017-06-01

    We investigate parameters of two high-mass X-ray binary systems IGR J17544-2619 and IGR J21343+4738 discovered by INTEGRAL space observatory by using optical data of Russian Turkish Telescope (RTT-150). Long-term optical observations of X-ray binary systems IGR J17544-2619 and IGR J21343+4738 were carried out in 2007-2015. Based on the RTT-150 data we estimated orbital periods of these systems. We have modeled the profiles of line HeI 6678 Å in spectra of studied optical stars and obtain the parameters of the star's atmosphere.

  10. Real-time process monitoring in a semi-continuous fluid-bed dryer - microwave resonance technology versus near-infrared spectroscopy.

    Science.gov (United States)

    Peters, Johanna; Teske, Andreas; Taute, Wolfgang; Döscher, Claas; Höft, Michael; Knöchel, Reinhard; Breitkreutz, Jörg

    2018-02-15

    The trend towards continuous manufacturing in the pharmaceutical industry is associated with an increasing demand for advanced control strategies. It is a mandatory requirement to obtain reliable real-time information on critical quality attributes (CQA) during every process step as the decision on diversion of material needs to be performed fast and automatically. Where possible, production equipment should provide redundant systems for in-process control (IPC) measurements to ensure continuous process monitoring even if one of the systems is not available. In this paper, two methods for real-time monitoring of granule moisture in a semi-continuous fluid-bed drying unit are compared. While near-infrared (NIR) spectroscopy has already proven to be a suitable process analytical technology (PAT) tool for moisture measurements in fluid-bed applications, microwave resonance technology (MRT) showed difficulties to monitor moistures above 8% until recently. The results indicate, that the newly developed MRT sensor operating at four resonances is capable to compete with NIR spectroscopy. While NIR spectra were preprocessed by mean centering and first derivative before application of partial least squares (PLS) regression to build predictive models (RMSEP = 0.20%), microwave moisture values of two resonances sufficed to build a statistically close multiple linear regression (MLR) model (RMSEP = 0.07%) for moisture prediction. Thereby, it could be verified that moisture monitoring by MRT sensor systems could be a valuable alternative to NIR spectroscopy or could be used as a redundant system providing great ease of application. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Microwave power engineering generation, transmission, rectification

    CERN Document Server

    Okress, Ernest C

    1968-01-01

    Microwave Power Engineering, Volume 1: Generation, Transmission, Rectification considers the components, systems, and applications and the prevailing limitations of the microwave power technology. This book contains four chapters and begins with an introduction to the basic concept and developments of microwave power technology. The second chapter deals with the development of the main classes of high-power microwave and optical frequency power generators, such as magnetrons, crossed-field amplifiers, klystrons, beam plasma amplifiers, crossed-field noise sources, triodes, lasers. The third

  12. EDITORIAL: Microwave Moisture Measurements

    Science.gov (United States)

    Kaatze, Udo; Kupfer, Klaus; Hübner, Christof

    2007-04-01

    microwave applications. Dr Kraszewski was a pioneer in moisture content sensing and the founder of microwave aquametry. He organized the first conferences on electromagnetic wave interactions with water and moist substances and helped to maintain the progress of microwave aquametry research internationally. Andrzej Kraszewski is missed by the microwave moisture measurement community who appreciated both his unusual technical ability and his pleasant and endearing character. Andrzej W Kraszewski, 1933-2006 We hope you will enjoy reading these papers and will extend your scientific curiosity to this field. Finally, we would like to thank all the authors, referees and the staff of Measurement Science and Technology for their contributions and support which have made the publication of this special issue possible.

  13. Review on Microwave-Matter Interaction Fundamentals and Efficient Microwave-Associated Heating Strategies

    Science.gov (United States)

    Sun, Jing; Wang, Wenlong; Yue, Qinyan

    2016-01-01

    Microwave heating is rapidly emerging as an effective and efficient tool in various technological and scientific fields. A comprehensive understanding of the fundamentals of microwave–matter interactions is the precondition for better utilization of microwave technology. However, microwave heating is usually only known as dielectric heating, and the contribution of the magnetic field component of microwaves is often ignored, which, in fact, contributes greatly to microwave heating of some aqueous electrolyte solutions, magnetic dielectric materials and certain conductive powder materials, etc. This paper focuses on this point and presents a careful review of microwave heating mechanisms in a comprehensive manner. Moreover, in addition to the acknowledged conventional microwave heating mechanisms, the special interaction mechanisms between microwave and metal-based materials are attracting increasing interest for a variety of metallurgical, plasma and discharge applications, and therefore are reviewed particularly regarding the aspects of the reflection, heating and discharge effects. Finally, several distinct strategies to improve microwave energy utilization efficiencies are proposed and discussed with the aim of tackling the energy-efficiency-related issues arising from the application of microwave heating. This work can present a strategic guideline for the developed understanding and utilization of the microwave heating technology. PMID:28773355

  14. Microwave solidification project overview

    Energy Technology Data Exchange (ETDEWEB)

    Sprenger, G.

    1993-01-01

    The Rocky Flats Plant Microwave Solidification Project has application potential to the Mixed Waste Treatment Project and the The Mixed Waste Integrated Program. The technical areas being addressed include (1) waste destruction and stabilization; (2) final waste form; and (3) front-end waste handling and feed preparation. This document covers need for such a program; technology description; significance; regulatory requirements; and accomplishments to date. A list of significant reports published under this project is included.

  15. Microwave solidification project overview

    International Nuclear Information System (INIS)

    Sprenger, G.

    1993-01-01

    The Rocky Flats Plant Microwave Solidification Project has application potential to the Mixed Waste Treatment Project and the The Mixed Waste Integrated Program. The technical areas being addressed include (1) waste destruction and stabilization; (2) final waste form; and (3) front-end waste handling and feed preparation. This document covers need for such a program; technology description; significance; regulatory requirements; and accomplishments to date. A list of significant reports published under this project is included

  16. A Study of Chemical Composition of δ Scuti-Type Stars Based on the Observations with the BTA and RTT-150

    Science.gov (United States)

    Galeev, A. I.; Berdnikova, V. M.; Ivanova, D. V.; Kudryavtsev, D. O.; Shimanskaya, N. N.; Shimansky, V. V.; Balashova, M. O.

    2017-06-01

    The results of a study of a sample of δ Scuti-type stars obtained from the observations with the BTA and RTT-150 are presented. Based on photometric data, we measured and analyzed the fundamental parameters of all the studied stars. For eight stars (for two of them for the first time), the fundamental parameters of the atmospheres (Teff, log g, [Fe/H]) and the chemical composition for 29 elements in the LTE-approximation are received using spectroscopic observations. The chemical composition analysis demonstrates both the solar abundances of chemical elements and the anomalies of chemical composition typical of Am stars in the studied sample of δ Scuti-type stars.

  17. Microwave Tokamak Experiment: Overview and status

    International Nuclear Information System (INIS)

    1990-05-01

    The Microwave Tokamak Experiment, now under construction at the Laboratory, will use microwave heating from a free-electron laser. The intense microwave pulses will be injected into the tokamak to realize several goals, including a demonstration of the effects of localized heat deposition within magnetically confined plasma, a better understanding of energy confinement in tokamaks, and use of the new free-electron laser technology for plasma heating. 3 figs., 3 tabs

  18. Synthesis and characterization of Ni-Mo filler brazing alloy for Mo-W joining for microwave tube technology

    Directory of Open Access Journals (Sweden)

    Frank Ferrer Sene

    2013-04-01

    Full Text Available A brazing process based on Ni-Mo alloy was developed to join porous tungsten cathode bottom and dense molybdenum cathode body for microwave tubes manufacture. The Ni-Mo alloy was obtained by mixing and milling powders in the eutectic composition, and applied on the surface of the components. The brazing was made at 1400 °C by using induction heating in hydrogen for 5 minutes. Alumina surfaces were coated with the binder and analyzed by Energy Dispersive X-rays Fluorescence. The brazed samples were analyzed by Scanning Electron Microscopy coupled to Energy Dispersive Spectroscopy. Stress-strain tests were performed to determine the mechanical behavior of the joining. The quality of the brazing was evaluated by assuring the presence of a "meniscus" formed by the Ni-Mo alloy on the border of the tungsten and molybdenum joint, the absence of microstructural defects in the interface between the tungsten and molybdenum alloys, and the adhesion of the brazed components.

  19. Combining microwave resonance technology to multivariate data analysis as a novel PAT tool to improve process understanding in fluid bed granulation.

    Science.gov (United States)

    Lourenço, Vera; Herdling, Thorsten; Reich, Gabriele; Menezes, José C; Lochmann, Dirk

    2011-08-01

    A set of 192 fluid bed granulation batches at industrial scale were in-line monitored using microwave resonance technology (MRT) to determine moisture, temperature and density of the granules. Multivariate data analysis techniques such as multiway partial least squares (PLS), multiway principal component analysis (PCA) and multivariate batch control charts were applied onto collected batch data sets. The combination of all these techniques, along with off-line particle size measurements, led to significantly increased process understanding. A seasonality effect could be put into evidence that impacted further processing through its influence on the final granule size. Moreover, it was demonstrated by means of a PLS that a relation between the particle size and the MRT measurements can be quantitatively defined, highlighting a potential ability of the MRT sensor to predict information about the final granule size. This study has contributed to improve a fluid bed granulation process, and the process knowledge obtained shows that the product quality can be built in process design, following Quality by Design (QbD) and Process Analytical Technology (PAT) principles. Copyright © 2011. Published by Elsevier B.V.

  20. Cryogenic microwave channelized receiver

    International Nuclear Information System (INIS)

    Rauscher, C.; Pond, J.M.; Tait, G.B.

    1996-01-01

    The channelized receiver being presented demonstrates the use of high temperature superconductor technology in a microwave system setting where superconductor, microwave-monolithic-integrated-circuit, and hybrid-integrated-circuit components are united in one package and cooled to liquid-nitrogen temperatures. The receiver consists of a superconducting X-band four-channel demultiplexer with 100-MHz-wide channels, four commercial monolithically integrated mixers, and four custom-designed hybrid-circuit detectors containing heterostructure ramp diodes. The composite receiver unit has been integrated into the payload of the second-phase NRL high temperature superconductor space experiment (HTSSE-II). Prior to payload assembly, the response characteristics of the receiver were measured as functions of frequency, temperature, and drive levels. The article describes the circuitry, discusses the key issues related to design and implementation, and summarizes the experimental results

  1. Fast microwave assisted pyrolysis of biomass using microwave absorbent.

    Science.gov (United States)

    Borges, Fernanda Cabral; Du, Zhenyi; Xie, Qinglong; Trierweiler, Jorge Otávio; Cheng, Yanling; Wan, Yiqin; Liu, Yuhuan; Zhu, Rongbi; Lin, Xiangyang; Chen, Paul; Ruan, Roger

    2014-03-01

    A novel concept of fast microwave assisted pyrolysis (fMAP) in the presence of microwave absorbents was presented and examined. Wood sawdust and corn stover were pyrolyzed by means of microwave heating and silicon carbide (SiC) as microwave absorbent. The bio-oil was characterized, and the effects of temperature, feedstock loading, particle sizes, and vacuum degree were analyzed. For wood sawdust, a temperature of 480°C, 50 grit SiC, with 2g/min of biomass feeding, were the optimal conditions, with a maximum bio-oil yield of 65 wt.%. For corn stover, temperatures ranging from 490°C to 560°C, biomass particle sizes from 0.9mm to 1.9mm, and vacuum degree lower than 100mmHg obtained a maximum bio-oil yield of 64 wt.%. This study shows that the use of microwave absorbents for fMAP is feasible and a promising technology to improve the practical values and commercial application outlook of microwave based pyrolysis. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Microwave firing of MnZn-ferrites

    International Nuclear Information System (INIS)

    Tsakaloudi, V.; Papazoglou, E.; Zaspalis, V.T.

    2004-01-01

    Microwave firing is evaluated in comparison to conventional firing for MnZn-ferrites. For otherwise identical conditions, microwave firing results to higher densities and coarser microstructures. Initial magnetic permeability values (25 kHz, 25 deg. C, <0.1 mT) after conventional firing are approximately 5000, but the corresponding values after microwave firing are approximately 6000. Unlike the conventional firing process, the final density after microwave firing is increased by increasing the prefiring temperature. As appears from the results of this study, microwave firing could be in principle a promising MnZn-ferrite firing technology for materials to be used in high magnetic permeability applications. No advantages of microwave firing are evident for materials intended to be used in high field power applications

  3. Tunable Multiband Microwave Photonic Filters

    Directory of Open Access Journals (Sweden)

    Mable P. Fok

    2017-11-01

    Full Text Available The increasing demand for multifunctional devices, the use of cognitive wireless technology to solve the frequency resource shortage problem, as well as the capabilities and operational flexibility necessary to meet ever-changing environment result in an urgent need of multiband wireless communications. Spectral filter is an essential part of any communication systems, and in the case of multiband wireless communications, tunable multiband RF filters are required for channel selection, noise/interference removal, and RF signal processing. Unfortunately, it is difficult for RF electronics to achieve both tunable and multiband spectral filtering. Recent advancements of microwave photonics have proven itself to be a promising candidate to solve various challenges in RF electronics including spectral filtering, however, the development of multiband microwave photonic filtering still faces lots of difficulties, due to the limited scalability and tunability of existing microwave photonic schemes. In this review paper, we first discuss the challenges that were facing by multiband microwave photonic filter, then we review recent techniques that have been developed to tackle the challenge and lead to promising developments of tunable microwave photonic multiband filters. The successful design and implementation of tunable microwave photonic multiband filter facilitate the vision of dynamic multiband wireless communications and radio frequency signal processing for commercial, defense, and civilian applications.

  4. Nuclear-microwave-electric propulsion

    International Nuclear Information System (INIS)

    Nordley, G.D.; Brown, W.C.

    1986-01-01

    Electric propulsion can move more mass through space than chemical propulsion by virtue of the higher exhaust velocities achieved by electric propulsion devices. This performance is achieved at the expense of very heavy power sources or very long trip times, which in turn create technical and economic penalties of varying severity. These penalties include: higher operations costs, delayed availability of the payload, and increased exposure to Van Allen Belt radiation. It is proposed to reduce these penalties by physically separating the power source from the propulsion and use microwave energy beaming technology, recently explored and partially developed/tested for Solar Power Satellite concept studies, as an extension cord. This paper summarizes the state of the art of the technology needed for space based beam microwave power cost/performance trades involved with the use beamed microwave/electric propulsion for some typical orbit transfer missions and offers some suggestions for additional work

  5. Advanced Microwave Circuits and Systems

    DEFF Research Database (Denmark)

    This book is based on recent research work conducted by the authors dealing with the design and development of active and passive microwave components, integrated circuits and systems. It is divided into seven parts. In the first part comprising the first two chapters, alternative concepts...... amplifier architectures. In addition, distortion analysis and power combining techniques are considered. Another key element in most microwave systems is a signal generator. It forms the heart of all kinds of communication and radar systems. The fourth part of this book is dedicated to signal generators...... push currently available technologies to the limits. Some considerations to meet the growing requirements are provided in the fifth part of this book. The following part deals with circuits based on LTCC and MEMS technologies. The book concludes with chapters considering application of microwaves...

  6. Determination of chromium, iron and selenium in foodstuffs of animal origin by collision cell technology, inductively coupled plasma mass spectrometry (ICP-MS), after closed vessel microwave digestion

    International Nuclear Information System (INIS)

    Dufailly, Vincent; Noel, Laurent; Guerin, Thierry

    2006-01-01

    The determination of chromium ( 52 Cr), iron ( 56 Fe) and selenium ( 80 Se) isotopes in foodstuffs of animal origin has been performed by collision cell technology (CCT) mode using an inductively coupled plasma mass spectrometry (ICP-MS) as detector after closed vessel microwave digestion. To significantly decrease the argon-based interferences at mass to charge ratios (m/z): 52 ( 40 Ar 12 C), 56 ( 40 Ar 16 O) and 80 ( 40 Ar 40 Ar), the gas-flow rates of a helium and hydrogen mixture used in the hexapole collision cell were optimised to 1.5 ml min -1 H 2 and 0.5 ml min -1 He and the quadrupole bias was adjusted daily between -2 and -15 mV. Limits of quantification (LOQ) of 0.025, 0.086 and 0.041 mg kg -1 for Cr, Fe and Se, respectively, in 6% HNO 3 were estimated under optimized CCT conditions. These LOQ were improved by a factor of approximately 10 for each element compared to standard mode. Precision under repeatability, intermediate precision reproducibility and trueness have been tested on nine different certified reference materials in foodstuffs of animal origin and on an external proficiency testing scheme. The results obtained for chromium, iron and selenium were in all cases in good agreement with the certified values and trueness was improved, compared to those obtained in standard mode

  7. Prospects of microwave processing: An overview

    Indian Academy of Sciences (India)

    Administrator

    Microstructures of sintered titania samples: (a) microwave and (b) conventional. Figure 5. ..... contaminated soil vitrification, volatile organic compounds treatment and ... ficant advancements will take place in the science and technology of ...

  8. Microwave Inspection Nondestructive Imaging Array, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — To address the NASA need for advanced NDE sensor technologies for structural materials, Physical Optics Corporation (POC) proposes to develop a new Microwave...

  9. Practical microwave electron devices

    CERN Document Server

    Meurant, Gerard

    2013-01-01

    Practical Microwave Electron Devices provides an understanding of microwave electron devices and their applications. All areas of microwave electron devices are covered. These include microwave solid-state devices, including popular microwave transistors and both passive and active diodes; quantum electron devices; thermionic devices (including relativistic thermionic devices); and ferrimagnetic electron devices. The design of each of these devices is discussed as well as their applications, including oscillation, amplification, switching, modulation, demodulation, and parametric interactions.

  10. Determination of chromium, iron and selenium in foodstuffs of animal origin by collision cell technology, inductively coupled plasma mass spectrometry (ICP-MS), after closed vessel microwave digestion

    Energy Technology Data Exchange (ETDEWEB)

    Dufailly, Vincent [Agence Francaise de Securite Sanitaire des Aliments - Laboratoire d' Etudes et de Recherches sur la Qualite des Aliments et des procedees agroalimentaires - Unite des Contaminants Inorganiques et Mineraux de l' Environnement, 23, avenue du General de Gaulle, F-94706 Maisons-Alfort Cedex (France); Noel, Laurent [Agence Francaise de Securite Sanitaire des Aliments - Laboratoire d' Etudes et de Recherches sur la Qualite des Aliments et des procedees agroalimentaires - Unite des Contaminants Inorganiques et Mineraux de l' Environnement, 23, avenue du General de Gaulle, F-94706 Maisons-Alfort Cedex (France); Guerin, Thierry [Agence Francaise de Securite Sanitaire des Aliments - Laboratoire d' Etudes et de Recherches sur la Qualite des Aliments et des procedees agroalimentaires - Unite des Contaminants Inorganiques et Mineraux de l' Environnement, 23, avenue du General de Gaulle, F-94706 Maisons-Alfort Cedex (France)]. E-mail: t.guerin@afssa.fr

    2006-04-21

    The determination of chromium ({sup 52}Cr), iron ({sup 56}Fe) and selenium ({sup 80}Se) isotopes in foodstuffs of animal origin has been performed by collision cell technology (CCT) mode using an inductively coupled plasma mass spectrometry (ICP-MS) as detector after closed vessel microwave digestion. To significantly decrease the argon-based interferences at mass to charge ratios (m/z): 52 ({sup 40}Ar{sup 12}C), 56 ({sup 40}Ar{sup 16}O) and 80 ({sup 40}Ar{sup 40}Ar), the gas-flow rates of a helium and hydrogen mixture used in the hexapole collision cell were optimised to 1.5 ml min{sup -1} H{sub 2} and 0.5 ml min{sup -1} He and the quadrupole bias was adjusted daily between -2 and -15 mV. Limits of quantification (LOQ) of 0.025, 0.086 and 0.041 mg kg{sup -1} for Cr, Fe and Se, respectively, in 6% HNO{sub 3} were estimated under optimized CCT conditions. These LOQ were improved by a factor of approximately 10 for each element compared to standard mode. Precision under repeatability, intermediate precision reproducibility and trueness have been tested on nine different certified reference materials in foodstuffs of animal origin and on an external proficiency testing scheme. The results obtained for chromium, iron and selenium were in all cases in good agreement with the certified values and trueness was improved, compared to those obtained in standard mode.

  11. Quantum teleportation of propagating quantum microwaves

    Energy Technology Data Exchange (ETDEWEB)

    Di Candia, R.; Felicetti, S.; Sanz, M. [University of the Basque Country UPV/EHU, Department of Physical Chemistry, Bilbao (Spain); Fedorov, K.G.; Menzel, E.P. [Bayerische Akademie der Wissenschaften, Walther-Meissner-Institut, Garching (Germany); Technische Universitaet Muenchen, Physik-Department, Garching (Germany); Zhong, L.; Deppe, F.; Gross, R. [Bayerische Akademie der Wissenschaften, Walther-Meissner-Institut, Garching (Germany); Technische Universitaet Muenchen, Physik-Department, Garching (Germany); Nanosystems Initiative Munich (NIM), Muenchen (Germany); Marx, A. [Bayerische Akademie der Wissenschaften, Walther-Meissner-Institut, Garching (Germany); Solano, E. [University of the Basque Country UPV/EHU, Department of Physical Chemistry, Bilbao (Spain); Basque Foundation for Science, IKERBASQUE, Bilbao (Spain)

    2015-12-15

    Propagating quantum microwaves have been proposed and successfully implemented to generate entanglement, thereby establishing a promising platform for the realisation of a quantum communication channel. However, the implementation of quantum teleportation with photons in the microwave regime is still absent. At the same time, recent developments in the field show that this key protocol could be feasible with current technology, which would pave the way to boost the field of microwave quantum communication. Here, we discuss the feasibility of a possible implementation of microwave quantum teleportation in a realistic scenario with losses. Furthermore, we propose how to implement quantum repeaters in the microwave regime without using photodetection, a key prerequisite to achieve long distance entanglement distribution. (orig.)

  12. Quantum teleportation of propagating quantum microwaves

    International Nuclear Information System (INIS)

    Di Candia, R.; Felicetti, S.; Sanz, M.; Fedorov, K.G.; Menzel, E.P.; Zhong, L.; Deppe, F.; Gross, R.; Marx, A.; Solano, E.

    2015-01-01

    Propagating quantum microwaves have been proposed and successfully implemented to generate entanglement, thereby establishing a promising platform for the realisation of a quantum communication channel. However, the implementation of quantum teleportation with photons in the microwave regime is still absent. At the same time, recent developments in the field show that this key protocol could be feasible with current technology, which would pave the way to boost the field of microwave quantum communication. Here, we discuss the feasibility of a possible implementation of microwave quantum teleportation in a realistic scenario with losses. Furthermore, we propose how to implement quantum repeaters in the microwave regime without using photodetection, a key prerequisite to achieve long distance entanglement distribution. (orig.)

  13. Microwave sintering of ceramic materials

    Science.gov (United States)

    Karayannis, V. G.

    2016-11-01

    In the present study, the potential of microwave irradiation as an innovative energy- efficient alternative to conventional heating technologies in ceramic manufacturing is reviewed, addressing the advantages/disadvantages, while also commenting on future applications of possible commercial interest. Ceramic materials have been extensively studied and used due to several advantages they exhibit. Sintering ceramics using microwave radiation, a novel technology widely employed in various fields, can be an efficient, economic and environmentally-friendlier approach, to improve the consolidation efficiency and reduce the processing cycle-time, in order to attain substantial energy and cost savings. Microwave sintering provides efficient internal heating, as energy is supplied directly and penetrates the material. Since energy transfer occurs at a molecular level, heat is generated throughout the material, thus avoiding significant temperature gradients between the surface and the interior, which are frequently encountered at high heating rates upon conventional sintering. Thus, rapid, volumetric and uniform heating of various raw materials and secondary resources for ceramic production is possible, with limited grain coarsening, leading to accelerated densification, and uniform and fine-grained microstructures, with enhanced mechanical performance. This is particularly important for manufacturing large-size ceramic products of quality, and also for specialty ceramic materials such as bioceramics and electroceramics. Critical parameters for the process optimization, including the electromagnetic field distribution, microwave-material interaction, heat transfer mechanisms and material transformations, should be taken into consideration.

  14. Microwave heating type evaporator

    International Nuclear Information System (INIS)

    Taura, Masazumi; Nishi, Akio; Morimoto, Takashi; Izumi, Jun; Tamura, Kazuo; Morooka, Akihiko.

    1987-01-01

    Purpose: To prevent evaporization stills against corrosion due to radioactive liquid wastes. Constitution: Microwaves are supplied from a microwave generator by way of a wave guide tube and through a microwave permeation window to the inside of an evaporatization still. A matching device is attached to the wave guide tube for transmitting the microwaves in order to match the impedance. When the microwaves are supplied to the inside of the evaporization still, radioactive liquid wastes supplied from a liquid feed port by way of a spray tower to the inside of the evaporization still is heated and evaporated by the induction heating of the microwaves. (Seki, T.)

  15. Application of high power microwave vacuum electron devices

    International Nuclear Information System (INIS)

    Ding Yaogen; Liu Pukun; Zhang Zhaochuan; Wang Yong; Shen Bin

    2011-01-01

    High power microwave vacuum electron devices can work at high frequency, high peak and average power. They have been widely used in military and civil microwave electron systems, such as radar, communication,countermeasure, TV broadcast, particle accelerators, plasma heating devices of fusion, microwave sensing and microwave heating. In scientific research, high power microwave vacuum electron devices are used mainly on high energy particle accelerator and fusion research. The devices include high peak power klystron, CW and long pulse high power klystron, multi-beam klystron,and high power gyrotron. In national economy, high power microwave vacuum electron devices are used mainly on weather and navigation radar, medical and radiation accelerator, TV broadcast and communication system. The devices include high power pulse and CW klystron, extended interaction klystron, traveling wave tube (TWT), magnetron and induced output tube (IOT). The state of art, common technology problems and trends of high power microwave vacuum electron devices are introduced in this paper. (authors)

  16. Microwave hematoma detector

    Science.gov (United States)

    Haddad, Waleed S.; Trebes, James E.; Matthews, Dennis L.

    2001-01-01

    The Microwave Hematoma Detector is a non-invasive device designed to detect and localize blood pooling and clots near the outer surface of the body. While being geared towards finding sub-dural and epi-dural hematomas, the device can be used to detect blood pooling anywhere near the surface of the body. Modified versions of the device can also detect pneumothorax, organ hemorrhage, atherosclerotic plaque in the carotid arteries, evaluate perfusion (blood flow) at or near the body surface, body tissue damage at or near the surface (especially for burn assessment) and be used in a number of NDE applications. The device is based on low power pulsed microwave technology combined with a specialized antenna, signal processing/recognition algorithms and a disposable cap worn by the patient which will facilitate accurate mapping of the brain and proper function of the instrument. The invention may be used for rapid, non-invasive detection of sub-dural or epi-dural hematoma in human or animal patients, detection of hemorrhage within approximately 5 cm of the outer surface anywhere on a patient's body.

  17. Advances in microwaves 7

    CERN Document Server

    Young, Leo

    2013-01-01

    Advances in Microwaves, Volume 7 covers the developments in the study of microwaves. The book discusses the effect of surface roughness on the propagation of the TEM mode, as well as the voltage breakdown of microwave antennas. The text also describes the theory and design considerations of single slotted-waveguide linear arrays and the techniques and theories that led to the achievement of wide bandwidths and ultralow noise temperatures for communication applications. The book will prove invaluable to microwave engineers.

  18. Cosmic Microwave Background Timeline

    Science.gov (United States)

    Cosmic Microwave Background Timeline 1934 : Richard Tolman shows that blackbody radiation in an will have a blackbody cosmic microwave background with temperature about 5 K 1955: Tigran Shmaonov anisotropy in the cosmic microwave background, this strongly supports the big bang model with gravitational

  19. Diamond Windows for High Powered Microwave Transmission. Final Report

    International Nuclear Information System (INIS)

    Gat, R.

    2011-01-01

    This phase II SBIR developed technology for manufacturing diamond windows for use in high energy density photon transmission e.g. microwave or laser light photons. Microwave sources used in fusion research require microwave extraction windows with high thermal conductivity, low microwave absorption, and low resistance to thermal cracking. Newly developed, man made diamond windows have all three of these properties, but these windows are prohibitively expensive. This limits the natural progress of these important technologies to higher powers and slows the development of additional applications. This project developed a lower cost process for manufacturing diamond windows using microwave plasma. Diamond windows were deposited. A grinding process was used to provide optical smoothness for 2 cm diameter diamond windows that met the parallelism specifications for fusion beam windows. The microwave transmission performance (loss tangent) of one of the windows was measured at 95GHz to be less than 10-4, meeting specifications for utilization in the ITER tokamak.

  20. Proceedings of microwave processing of materials 3

    International Nuclear Information System (INIS)

    Beatty, R.L.

    1992-01-01

    This book contains proceedings of the third MRS Symposium on Microwave Processing of Materials. Topics covered include: Microwave Processing Overviews, Numerical Modeling Techniques, Microwave Processing System Design, Microwave/Plasma Processing, Microwave/Materials Interactions, Microwave Processing of Ceramics, Microwave Processing of Polymers, Microwave Processing of Hazardous Wastes, Microwave NDE Techniques and Dielectric Properties and Measurements

  1. Microwave ablation devices for interventional oncology.

    Science.gov (United States)

    Ward, Robert C; Healey, Terrance T; Dupuy, Damian E

    2013-03-01

    Microwave ablation is one of the several options in the ablation armamentarium for the treatment of malignancy, offering several potential benefits when compared with other ablation, radiation, surgical and medical treatment modalities. The basic microwave system consists of the generator, power distribution system and antennas. Often under image (computed tomography or ultrasound) guidance, a needle-like antenna is inserted percutaneously into the tumor, where local microwave electromagnetic radiation is emitted from the probe's active tip, producing frictional tissue heating, capable of causing cell death by coagulation necrosis. Half of the microwave ablation systems use a 915 MHz generator and the other half use a 2450 MHz generator. To date, there are no completed clinical trials comparing microwave devices head-to-head. Prospective comparisons of microwave technology with other treatment alternatives, as well as head-to-head comparison with each microwave device, is needed if this promising field will garner more widespread support and use in the oncology community.

  2. Microwave heating denitration device

    International Nuclear Information System (INIS)

    Sato, Hajime; Morisue, Tetsuo.

    1984-01-01

    Purpose: To suppress energy consumption due to a reflection of microwaves. Constitution: Microwaves are irradiated to the nitrate solution containing nuclear fuel materials, to cause denitrating reaction under heating and obtain oxides of the nuclear fuel materials. A microwave heating and evaporation can for reserving the nitrate solution is disposed slantwise relative to the horizontal plane and a microwave heating device is connected to the evaporation can, and inert gases for agitation are supplied to the solution within the can. Since the evaporation can is slanted, wasteful energy consumption due to the reflection of the microwaves can be suppressed. (Moriyama, K.)

  3. Microwave Thermal Propulsion

    Science.gov (United States)

    Parkin, Kevin L. G.; Lambot, Thomas

    2017-01-01

    We have conducted research in microwave thermal propulsion as part of the space exploration access technologies (SEAT) research program, a cooperative agreement (NNX09AF52A) between NASA and Carnegie Mellon University. The SEAT program commenced on the 19th of February 2009 and concluded on the 30th of September 2015. The DARPA/NASA Millimeter-wave Thermal Launch System (MTLS) project subsumed the SEAT program from May 2012 to March 2014 and one of us (Parkin) served as its principal investigator and chief engineer. The MTLS project had no final report of its own, so we have included the MTLS work in this report and incorporate its conclusions here. In the six years from 2009 until 2015 there has been significant progress in millimeter-wave thermal rocketry (a subset of microwave thermal rocketry), most of which has been made under the auspices of the SEAT and MTLS programs. This final report is intended for multiple audiences. For researchers, we present techniques that we have developed to simplify and quantify the performance of thermal rockets and their constituent technologies. For program managers, we detail the facilities that we have built and the outcomes of experiments that were conducted using them. We also include incomplete and unfruitful lines of research. For decision-makers, we introduce the millimeter-wave thermal rocket in historical context. Considering the economic significance of space launch, we present a brief but significant cost-benefit analysis, for the first time showing that there is a compelling economic case for replacing conventional rockets with millimeter-wave thermal rockets.

  4. The microwave effects on the properties of alumina at high frequencies of microwave sintering

    Energy Technology Data Exchange (ETDEWEB)

    Sudiana, I. Nyoman, E-mail: sudiana75@yahoo.com; Ngkoimani, La Ode; Usman, Ida [Department of Physics, Faculty of Mathematic and Natural Science, Halu Oleo University, Kampus Bumi Tridharma Anduonohu, Kendari 93232 (Indonesia); Mitsudo, Seitaro; Sako, Katsuhide; Inagaki, Shunsuke [Research Center for Development of Far-Infrared Region, University of Fukui, 3-9-1 Bunkyo, Fukui-shi 910-8507 (Japan); Aripin, H. [Center for Material Processing and Renewable Energy, Faculty of Learning Teacher and Education Science, Siliwangi University, Jl. Siliwangi 24 Tasikmalaya 46115, West Java (Indonesia)

    2016-03-11

    Microwave sintering of materials has attracted much research interest because of its significant advantages (e.g. reduced sintering temperatures and soaking times) over the conventional heating. Most researchers compared processes that occurred during the microwave and conventional heating at the same temperature and time. The enhancements found in the former method are indicated as a 'non-thermal effect' which is usually used for explaining the phenomena in microwave processing. Numerous recent studies have been focused on the effect to elucidate the microwave interaction mechanism with materials. Moreover, recent progress on microwave sources such as gyrotrons has opened the possibility for processing materials by using a higher microwave frequency. Therefore, the technology is expected to exhibit a stronger non-thermal effect. This paper presents results from a series of experiments to study the non-thermal effect on microwave sintered alumina. Sintering by using a wide rage of microwave frequencies up to 300 GHz as well as a conventional furnace was carried out. The linear shrinkages of samples for each sintering method were measured. Pores and grains taken from scanning electron microstructure (SEM) images of cut surfaces were also examined. The results of a comparative study of the shrinkages and microstructure evolutions of the sintered samples under annealing in microwave heating systems and in an electric furnace were analyzed. A notably different behavior of the shrinkages and microstructures of alumina after being annealed was found. The results suggested that microwave radiations provided an additional force for mass transports. The results also indicated that the sintering process depended on microwave frequencies.

  5. The microwave effects on the properties of alumina at high frequencies of microwave sintering

    International Nuclear Information System (INIS)

    Sudiana, I. Nyoman; Ngkoimani, La Ode; Usman, Ida; Mitsudo, Seitaro; Sako, Katsuhide; Inagaki, Shunsuke; Aripin, H.

    2016-01-01

    Microwave sintering of materials has attracted much research interest because of its significant advantages (e.g. reduced sintering temperatures and soaking times) over the conventional heating. Most researchers compared processes that occurred during the microwave and conventional heating at the same temperature and time. The enhancements found in the former method are indicated as a 'non-thermal effect' which is usually used for explaining the phenomena in microwave processing. Numerous recent studies have been focused on the effect to elucidate the microwave interaction mechanism with materials. Moreover, recent progress on microwave sources such as gyrotrons has opened the possibility for processing materials by using a higher microwave frequency. Therefore, the technology is expected to exhibit a stronger non-thermal effect. This paper presents results from a series of experiments to study the non-thermal effect on microwave sintered alumina. Sintering by using a wide rage of microwave frequencies up to 300 GHz as well as a conventional furnace was carried out. The linear shrinkages of samples for each sintering method were measured. Pores and grains taken from scanning electron microstructure (SEM) images of cut surfaces were also examined. The results of a comparative study of the shrinkages and microstructure evolutions of the sintered samples under annealing in microwave heating systems and in an electric furnace were analyzed. A notably different behavior of the shrinkages and microstructures of alumina after being annealed was found. The results suggested that microwave radiations provided an additional force for mass transports. The results also indicated that the sintering process depended on microwave frequencies.

  6. RTT et Santé : Petite chronique d’un égarement collectif Reduction in working time and health: Short article about a collective aberration RTT y salud : pequeña crónica de un extravío colectivo

    Directory of Open Access Journals (Sweden)

    Anne Flottes

    2006-05-01

    Full Text Available Consultante répondant à des demandes concernant les atteintes à la santé mentale des salariés, l’auteure s’interroge sur un paradoxe récurrent de ces situations : les salariés qui se disent globalement satisfaits de la réduction du temps de travail affirment aussi que « depuis les 35 heures, ça ne va plus ». Loin de toute tentative d’évaluation des effets de la RTT sur les conditions de travail, elle tente d’instruire cette énigme en articulant l’approche psychodynamique du travail, l’historique de la réglementation et des images médiatiques, et la clinique de ses interventions. Elle dessine progressivement un cercle vicieux défensif de paralysie de la pensée et de l’action et de perte d’estime de soi délétère. La RTT ne serait pas la cause de la dégradation de la santé mentale, elle représenterait l’instant emblématique de l’engagement involontaire mais pas inconscient des salariés, syndicats, politiques, dans le maintien du système qu’ils réprouvent : en acceptant de se ranger sans débat sous la bannière des stéréotypes de la fatalité économique, de la « guerre » commerciale et des critères gestionnaires d’évaluation du travail, ils ont fait l’économie de l’embarras des conflits d’intérêt, des confrontations éthiques et techniques sur les pratiques quotidiennes de travail, mais ils ont aussi perdu l’ancrage permettant de subvertir les prescriptions ; il leur faut porter solitairement le doute et la culpabilité. D’où une dérive de l’action collective et individuelle vers la reconnaissance des « souffrances », la condamnation des « harceleurs » et le soin psychologique des « victimes ». L’enjeu de santé est de revenir dans le registre de la conflictualité sociale et de restaurer la capacité collective à penser le « travailler ».As a consultant responding to requests about impacts on employees’ mental health, the author wonders about a

  7. A monolithic integrated photonic microwave filter

    Science.gov (United States)

    Fandiño, Javier S.; Muñoz, Pascual; Doménech, David; Capmany, José

    2017-02-01

    Meeting the increasing demand for capacity in wireless networks requires the harnessing of higher regions in the radiofrequency spectrum, reducing cell size, as well as more compact, agile and power-efficient base stations that are capable of smoothly interfacing the radio and fibre segments. Fully functional microwave photonic chips are promising candidates in attempts to meet these goals. In recent years, many integrated microwave photonic chips have been reported in different technologies. To the best of our knowledge, none has monolithically integrated all the main active and passive optoelectronic components. Here, we report the first demonstration of a tunable microwave photonics filter that is monolithically integrated into an indium phosphide chip. The reconfigurable radiofrequency photonic filter includes all the necessary elements (for example, lasers, modulators and photodetectors), and its response can be tuned by means of control electric currents. This is an important step in demonstrating the feasibility of integrated and programmable microwave photonic processors.

  8. On-Chip Microwave Quantum Hall Circulator

    Directory of Open Access Journals (Sweden)

    A. C. Mahoney

    2017-01-01

    Full Text Available Circulators are nonreciprocal circuit elements that are integral to technologies including radar systems, microwave communication transceivers, and the readout of quantum information devices. Their nonreciprocity arises from the interference of microwaves over the centimeter scale of the signal wavelength, in the presence of bulky magnetic media that breaks time-reversal symmetry. Here, we realize a completely passive on-chip microwave circulator with size 1/1000th the wavelength by exploiting the chiral, “slow-light” response of a two-dimensional electron gas in the quantum Hall regime. For an integrated GaAs device with 330  μm diameter and about 1-GHz center frequency, a nonreciprocity of 25 dB is observed over a 50-MHz bandwidth. Furthermore, the nonreciprocity can be dynamically tuned by varying the voltage at the port, an aspect that may enable reconfigurable passive routing of microwave signals on chip.

  9. RF and microwave microelectronics packaging II

    CERN Document Server

    Sturdivant, Rick

    2017-01-01

    Reviews RF, microwave, and microelectronics assembly process, quality control, and failure analysis Bridges the gap between low cost commercial and hi-res RF/Microwave packaging technologies Engages in an in-depth discussion of challenges in packaging and assembly of advanced high-power amplifiers This book presents the latest developments in packaging for high-frequency electronics. It is a companion volume to “RF and Microwave Microelectronics Packaging” (2010) and covers the latest developments in thermal management, electrical/RF/thermal-mechanical designs and simulations, packaging and processing methods, and other RF and microwave packaging topics. Chapters provide detailed coverage of phased arrays, T/R modules, 3D transitions, high thermal conductivity materials, carbon nanotubes and graphene advanced materials, and chip size packaging for RF MEMS. It appeals to practicing engineers in the electronic packaging and high-frequency electronics domain, and to academic researchers interested in underst...

  10. Microwave Regenerable Air Purification Device

    Science.gov (United States)

    Atwater, James E.; Holtsnider, John T.; Wheeler, Richard R., Jr.

    1996-01-01

    The feasibility of using microwave power to thermally regenerate sorbents loaded with water vapor, CO2, and organic contaminants has been rigorously demonstrated. Sorbents challenged with air containing 0.5% CO2, 300 ppm acetone, 50 ppm trichloroethylene, and saturated with water vapor have been regenerated, singly and in combination. Microwave transmission, reflection, and phase shift has also been determined for a variety of sorbents over the frequency range between 1.3-2.7 GHz. This innovative technology offers the potential for significant energy savings in comparison to current resistive heating methods because energy is absorbed directly by the material to be heated. Conductive, convective and radiative losses are minimized. Extremely rapid heating is also possible, i.e., 1400 C in less than 60 seconds. Microwave powered thermal desorption is directly applicable to the needs of Advance Life Support in general, and of EVA in particular. Additionally, the applicability of two specific commercial applications arising from this technology have been demonstrated: the recovery for re-use of acetone (and similar solvents) from industrial waste streams using a carbon based molecular sieve; and the separation and destruction of trichloroethylene using ZSM-5 synthetic zeolite catalyst, a predominant halocarbon environmental contaminant. Based upon these results, Phase II development is strongly recommended.

  11. A low-loss, continuously tunable microwave notch filter

    DEFF Research Database (Denmark)

    Acar, Öncel; Johansen, Tom Keinicke; Zhurbenko, Vitaliy

    2016-01-01

    The development in high-end microwave transceiver systems toward the software defined radio has brought about the need for tunable frontend filters. Although the problem is being tackled by the microwave community, there still appears to be an unmet demand for practical tunable filter technologies...

  12. Microwave regeneration of molecular sieves

    International Nuclear Information System (INIS)

    Singh, V.P.

    1984-05-01

    Molecular sieve driers have been included in the design of tritium handling systems for fusion reactors. In these systems there is a need to maintain extremely low exit dew points from the driers as well as a capability to rapidly reduce tritium concentrations following an accident. The required capacity of the driers is very high. The conventional method of regenerating these sieves after a water adsorption cycle is with hot air. However, because water is rapidly heated by microwave energy, this technology may be suitable for decreasing the bed regeneration time and hence may allow reduced capital and operating costs associated with a smaller bed. The present study was conducted to obtain preliminary information on the technical feasibility of regenerating molecular sieves with microwave energy. The study concentrated on Type 4A molecular sieve with a few tests on Type 13X sieve and also a silica gel adsorbent

  13. Rapid biodiesel production using wet microalgae via microwave irradiation

    International Nuclear Information System (INIS)

    Wahidin, Suzana; Idris, Ani; Shaleh, Sitti Raehanah Muhamad

    2014-01-01

    Highlights: • Lipid was directly extracted from wet microalgae using microwave irradiation. • The microwave irradiation and water bath-assisted solvent extraction are applied. • Cell walls are significantly disrupted under microwave irradiation. • Highly disrupted cell walls led to higher biodiesel yield in microwave irradiation. • Microwave irradiation is a promising direct technique with high biodiesel yields. - Abstract: The major challenges for industrial commercialized biodiesel production from microalgae are the high cost of downstream processing such as dewatering and drying, utilization of large volumes of solvent and laborious extraction processes. In order to address these issues the microwave irradiation method was used to produce biodiesel directly from wet microalgae biomass. This alternative method of biodiesel production from wet microalgae biomass is compared with the conventional water bath-assisted solvent extraction. The microwave irradiation extracted more lipids and high biodiesel conversion was obtained compared to the water bath-assisted extraction method due to the high cell disruption achieved and rapid transesterification. The total content of lipid extracted from microwave irradiation and water bath-assisted extraction were 38.31% and 23.01% respectively. The biodiesel produced using microwave irradiation was higher (86.41%) compared to the conventional method. Thus microwave irradiation is an attractive and promising technology to be used in the extraction and transesterification process for efficient biodiesel production

  14. Plasma relativistic microwave electronics

    International Nuclear Information System (INIS)

    Kuzelev, M.V.; Loza, O.T.; Rukhadze, A.A.; Strelkov, P.S.; Shkvarunets, A.G.

    2001-01-01

    One formulated the principles of plasma relativistic microwave electronics based on the induced Cherenkov radiation of electromagnetic waves at interaction of a relativistic electron beam with plasma. One developed the theory of plasma relativistic generators and accelerators of microwave radiation, designed and studied the prototypes of such devices. One studied theoretically the mechanisms of radiation, calculated the efficiencies and the frequency spectra of plasma relativistic microwave generators and accelerators. The theory findings are proved by the experiment: intensity of the designed sources of microwave radiation is equal to 500 μW, the frequency of microwave radiation is increased by 7 times (from 4 up to 28 GHz), the width of radiation frequency band may vary from several up to 100%. The designed sources of microwave radiation are no else compared in the electronics [ru

  15. A Review of Microwave-Assisted Reactions for Biodiesel Production

    Directory of Open Access Journals (Sweden)

    Saifuddin Nomanbhay

    2017-06-01

    Full Text Available The conversion of biomass into chemicals and biofuels is an active research area as trends move to replace fossil fuels with renewable resources due to society’s increased concern towards sustainability. In this context, microwave processing has emerged as a tool in organic synthesis and plays an important role in developing a more sustainable world. Integration of processing methods with microwave irradiation has resulted in a great reduction in the time required for many processes, while the reaction efficiencies have been increased markedly. Microwave processing produces a higher yield with a cleaner profile in comparison to other methods. The microwave processing is reported to be a better heating method than the conventional methods due to its unique thermal and non-thermal effects. This paper provides an insight into the theoretical aspects of microwave irradiation practices and highlights the importance of microwave processing. The potential of the microwave technology to accomplish superior outcomes over the conventional methods in biodiesel production is presented. A green process for biodiesel production using a non-catalytic method is still new and very costly because of the supercritical condition requirement. Hence, non-catalytic biodiesel conversion under ambient pressure using microwave technology must be developed, as the energy utilization for microwave-based biodiesel synthesis is reported to be lower and cost-effective.

  16. Microwave Resonators and Filters

    Science.gov (United States)

    2015-12-22

    1 Microwave Resonators and Filters Daniel E. Oates MIT Lincoln Laboratory 244 Wood St. Lexington, MA 02478 USA Email: oates@ll.mit.edu...explained in other chapters, the surface resistance of superconductors at microwave frequencies can be as much as three orders of magnitude lower than the...resonators and filters in the first edition of this handbook (Z.-Y. Shen 2003) discussed the then state of the art of microwave frequency applications

  17. [EVALUATION OF CHANGES OF GEOMETRICAL PARAMETERS OF ALGINATE DENTAL IMPRESSIONS DUE TO THE INFLUENCE OF CHEMICAL AND MICROWAVE DISINFECTION METHOD USING 3D TECHNOLOGIES].

    Science.gov (United States)

    Nespraydko, V P; Shevchuk, V A; Michaylov, A A; Lyseyko, N V

    2015-01-01

    This clinical and laboratory study evaluated the effect of two methods of disinfection in different modes at the volume changes of alginate dental impressions and plaster models poured from them, as compared to the same parameters of plastic master models (PMM), using three-dimensional non-contact laser scanner and software. Immersion chemical disinfection for 15 min, microwave disinfection at 354 W for 10 minutes and combined disinfection with the power of 319 W for 4 minutes did not significantly affect the volumetric dimensional accuracy of the alginate impressions (P > 0.05).

  18. Advanced microwave processing concepts

    Energy Technology Data Exchange (ETDEWEB)

    Lauf, R.J.; McMillan, A.D.; Paulauskas, F.L. [Oak Ridge National Laboratory, TN (United States)

    1995-05-01

    The purpose of this work is to explore the feasibility of several advanced microwave processing concepts to develop new energy-efficient materials and processes. The project includes two tasks: (1) commercialization of the variable-frequency microwave furnace; and (2) microwave curing of polymer composites. The variable frequency microwave furnace, whose initial conception and design was funded by the AIC Materials Program, will allow us, for the first time, to conduct microwave processing studies over a wide frequency range. This novel design uses a high-power traveling wave tube (TWT) originally developed for electronic warfare. By using this microwave source, one can not only select individual microwave frequencies for particular experiments, but also achieve uniform power densities over a large area by the superposition of many different frequencies. Microwave curing of thermoset resins will be studied because it hold the potential of in-situ curing of continuous-fiber composites for strong, lightweight components. Microwave heating can shorten curing times, provided issues of scaleup, uniformity, and thermal management can be adequately addressed.

  19. Advances in microwaves 3

    CERN Document Server

    Young, Leo

    2013-01-01

    Advances in Microwaves, Volume 3 covers the advances and applications of microwave signal transmission and Gunn devices. This volume contains six chapters and begins with descriptions of ground-station antennas for space communications. The succeeding chapters deal with beam waveguides, which offer interesting possibilities for transmitting microwave energy, as well as with parallel or tubular beams from antenna apertures. A chapter discusses the electron transfer mechanism and the velocity-field characteristics, with a particular emphasis on the microwave properties of Gunn oscillators. The l

  20. Applications of high power microwaves

    International Nuclear Information System (INIS)

    Benford, J.; Swegle, J.

    1993-01-01

    The authors address a number of applications for HPM technology. There is a strong symbiotic relationship between a developing technology and its emerging applications. New technologies can generate new applications. Conversely, applications can demand development of new technological capability. High-power microwave generating systems come with size and weight penalties and problems associated with the x-radiation and collection of the electron beam. Acceptance of these difficulties requires the identification of a set of applications for which high-power operation is either demanded or results in significant improvements in peRFormance. The authors identify the following applications, and discuss their requirements and operational issues: (1) High-energy RF acceleration; (2) Atmospheric modification (both to produce artificial ionospheric mirrors for radio waves and to save the ozone layer); (3) Radar; (4) Electronic warfare; and (5) Laser pumping. In addition, they discuss several applications requiring high average power than border on HPM, power beaming and plasma heating

  1. Rapid determination of eight bioactive alkaloids in Portulaca oleracea L. by the optimal microwave extraction combined with positive-negative conversion multiple reaction monitor (+/-MRM) technology.

    Science.gov (United States)

    Liang, Xiao; Tian, Jinlong; Li, Lingzhi; Gao, Jun; Zhang, Qingyi; Gao, Pinyi; Song, Shaojiang

    2014-03-01

    A rapid and reliable microwave extraction and the triple quadrupole-linear ion trap mass spectrometry method was developed and validated for the determination of eight alkaloids in Portulaca oleracea L. The optimal microwave extraction (MWE) condition was performed at 60 °C for 12 min with ethanol-water (70:30, v/v) as the extracting solvent, and the solvent to solid ratio was 30:1. The alkaloids were first detected simultaneously by electrospray ionization tandem mass spectrometry under positive-negative conversion multiple reaction monitor ((+/-)MRM) technique. With investigating three different columns, samples were separated in only 8 min on a Waters ACQUITY UPLC HSS T3 (50 × 2.1 mm(2), 1.8 μm) column using acetonitrile and formic acid-water solution as a mobile phase with a flow rate at 0.2 mL/min. All calibration curves showed good linearity (r>0.999) within the test ranges. The method developed was validated with acceptable sensitivity, intra- and inter-day precision, reproducibility, and extraction recoveries. It was successfully applied to the determination of eight alkaloids in Portulaca oleracea L. from different sources and different harvest periods. The method also provide a reference for extraction and determination of alkaloids in other complex systems. © 2013 Elsevier B.V. All rights reserved.

  2. A Review on Passive and Integrated Near-Field Microwave Biosensors

    Science.gov (United States)

    Guha, Subhajit; Jamal, Farabi Ibne

    2017-01-01

    In this paper we review the advancement of passive and integrated microwave biosensors. The interaction of microwave with biological material is discussed in this paper. Passive microwave biosensors are microwave structures, which are fabricated on a substrate and are used for sensing biological materials. On the other hand, integrated biosensors are microwave structures fabricated in standard semiconductor technology platform (CMOS or BiCMOS). The CMOS or BiCMOS sensor technology offers a more compact sensing approach which has the potential in the future for point of care testing systems. Various applications of the passive and the integrated sensors have been discussed in this review paper. PMID:28946617

  3. Microwave Enhanced Reactive Distillation

    NARCIS (Netherlands)

    Altman, E.

    2011-01-01

    The application of electromagnetic irradiation in form of microwaves (MW) has gathered the attention of the scientific community in recent years. MW used as an alternative energy source for chemical syntheses (microwave chemistry) can provide clear advantages over conventional heating methods in

  4. Microwave Breast Imaging Techniques

    DEFF Research Database (Denmark)

    Zhurbenko, Vitaliy; Rubæk, Tonny

    2010-01-01

    This paper outlines the applicability of microwave radiation for breast cancer detection. Microwave imaging systems are categorized based on their hardware architecture. The advantages and disadvantages of various imaging techniques are discussed. The fundamental tradeoffs are indicated between...... various requirements to be fulfilled in the design of an imaging system for breast cancer detection and some strategies to overcome these limitations....

  5. MICROWAVES IN ORGANIC SYNTHESIS

    Science.gov (United States)

    The effect of microwaves, a non-ionizing radiation, on organic reactions is described both in polar solvents and under solvent-free conditions. The special applications are highlighted in the context of solventless organic synthesis which involve microwave (MW) exposure of neat r...

  6. Variable frequency microwave heating apparatus

    Energy Technology Data Exchange (ETDEWEB)

    Bible, D.W.; Lauf, R.J.; Johnson, A.C.; Thigpen, L.T.

    1999-10-05

    A variable frequency microwave heating apparatus (10) designed to allow modulation of the frequency of the microwaves introduced into a multi-mode microwave cavity (34) for testing or other selected applications. The variable frequency microwave heating apparatus (10) includes a microwave signal generator (12) and a high-power microwave amplifier (20) or a high-power microwave oscillator (14). A power supply (22) is provided for operation of the high-power microwave oscillator (14) or microwave amplifier (20). A directional coupler (24) is provided for detecting the direction and amplitude of signals incident upon and reflected from the microwave cavity (34). A first power meter (30) is provided for measuring the power delivered to the microwave furnace (32). A second power meter (26) detects the magnitude of reflected power. Reflected power is dissipated in the reflected power load (28).

  7. Advancements of microwave diagnostics in magnetically confined plasmas

    NARCIS (Netherlands)

    Mase, A.; Kogi, Y.; Ito, N.; Yokota, Y.; Akaki, K.; Kawahata, K.; Nagayama, Y.; Tokuzawa, T.; Yamaguchi, S.; Hojo, H.; Oyama, N.; N C Luhmann Jr.,; Park, H. K.; Donne, A. J. H.

    2009-01-01

    Microwave to millimeter-wave diagnostic techniques such as interferometry, reflectometry, scattering and radiometry have been powerful tools for diagnosing magnetically confined plasmas. Recent advances in electronic devices and components together with computer technology have enabled the

  8. An experimental facility for microwave induced plasma processing of materials

    International Nuclear Information System (INIS)

    Patil, D.S.; Ramachandran, K.; Bhide, A.L.; Venkatramani, N.

    1997-01-01

    Microwave induced plasma processing offers many advantages over conventional processes. However this technology is in the development stage. This report gives a detailed information about a microwave plasma processing facility (2.45 GHz, 700 W) set up in the Laser and Plasma Technology Division. The equipment details and the results obtained on deposition of diamond like carbon (DLC) thin films and surface modification of polymer PET (polyethylene terephthalate) using this facility are given in this report. (author)

  9. Spectroscopic study of the optical counterpart to the fast X-ray transient IGR J17544-2619 based on observations at the 1.5-m RTT-150 telescope

    Science.gov (United States)

    Bikmaev, I. F.; Nikolaeva, E. A.; Shimansky, V. V.; Galeev, A. I.; Zhuchkov, R. Ya.; Irtuganov, E. N.; Melnikov, S. S.; Sakhibullin, N. A.; Grebenev, S. A.; Sharipova, L. M.

    2017-10-01

    We present the results of our long-term photometric and spectroscopic observations at the Russian-Turkish RTT-150 telescope for the optical counterpart to one of the best-known sources, representatives of the class of fast X-ray transients, IGR J17544-2619. Based on our optical data, we have determined for the first time the orbital and physical parameters of the binary system by the methods of Doppler spectroscopy.We have calculated theoretical spectra of the optical counterpart by applying non- LTE corrections for selected lines and obtained the parameters of the stellar atmosphere ( T eff = 33 000 K, log g = 3.85, R = 9.5 R ⊙, and M = 23 M ⊙). The latter suggest that the optical star is not a supergiant as has been thought previously.

  10. Nanoscale microwave microscopy using shielded cantilever probes

    KAUST Repository

    Lai, Keji; Kundhikanjana, Worasom; Kelly, Michael A.; Shen, Zhi-Xun

    2011-01-01

    Quantitative dielectric and conductivity mapping in the nanoscale is highly desirable for many research disciplines, but difficult to achieve through conventional transport or established microscopy techniques. Taking advantage of the micro-fabrication technology, we have developed cantilever-based near-field microwave probes with shielded structures. Sensitive microwave electronics and finite-element analysis modeling are also utilized for quantitative electrical imaging. The system is fully compatible with atomic force microscope platforms for convenient operation and easy integration of other modes and functions. The microscope is ideal for interdisciplinary research, with demonstrated examples in nano electronics, physics, material science, and biology.

  11. Microwave components for cellular portable radiotelephone

    Science.gov (United States)

    Muraguchi, Masahiro; Aikawa, Masayoshi

    1995-09-01

    Mobile and personal communication systems are expected to represent a huge market for microwave components in the coming years. A number of components in silicon bipolar, silicon Bi-CMOS, GaAs MESFET, HBT and HEMT are now becoming available for system application. There are tradeoffs among the competing technologies with regard to performance, cost, reliability and time-to-market. This paper describes process selection and requirements of cost and r.f. performances to microwave semiconductor components for digital cellular and cordless telephones. Furthermore, new circuit techniques which were developed by NTT are presented.

  12. Nanoscale microwave microscopy using shielded cantilever probes

    KAUST Repository

    Lai, Keji

    2011-04-21

    Quantitative dielectric and conductivity mapping in the nanoscale is highly desirable for many research disciplines, but difficult to achieve through conventional transport or established microscopy techniques. Taking advantage of the micro-fabrication technology, we have developed cantilever-based near-field microwave probes with shielded structures. Sensitive microwave electronics and finite-element analysis modeling are also utilized for quantitative electrical imaging. The system is fully compatible with atomic force microscope platforms for convenient operation and easy integration of other modes and functions. The microscope is ideal for interdisciplinary research, with demonstrated examples in nano electronics, physics, material science, and biology.

  13. Gold Nanoparticle Microwave Synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Krantz, Kelsie E. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Christian, Jonathan H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Coopersmith, Kaitlin [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Washington, II, Aaron L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Murph, Simona H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-07-27

    At the nanometer scale, numerous compounds display different properties than those found in bulk material that can prove useful in areas such as medicinal chemistry. Gold nanoparticles, for example, display promise in newly developed hyperthermia therapies for cancer treatment. Currently, gold nanoparticle synthesis is performed via the hot injection technique which has large variability in final particle size and a longer reaction time. One underdeveloped area by which these particles could be produced is through microwave synthesis. To initiate heating, microwaves agitate polar molecules creating a vibration that gives off the heat energy needed. Previous studies have used microwaves for gold nanoparticle synthesis; however, polar solvents were used that partially absorbed incident microwaves, leading to partial thermal heating of the sample rather than taking full advantage of the microwave to solely heat the gold nanoparticle precursors in a non-polar solution. Through this project, microwaves were utilized as the sole heat source, and non-polar solvents were used to explore the effects of microwave heating only as pertains to the precursor material. Our findings show that the use of non-polar solvents allows for more rapid heating as compared to polar solvents, and a reduction in reaction time from 10 minutes to 1 minute; this maximizes the efficiency of the reaction, and allows for reproducibility in the size/shape of the fabricated nanoparticles.

  14. Gold Nanoparticle Microwave Synthesis

    International Nuclear Information System (INIS)

    Krantz, Kelsie E.; Christian, Jonathan H.; Coopersmith, Kaitlin; Washington II, Aaron L.; Murph, Simona H.

    2016-01-01

    At the nanometer scale, numerous compounds display different properties than those found in bulk material that can prove useful in areas such as medicinal chemistry. Gold nanoparticles, for example, display promise in newly developed hyperthermia therapies for cancer treatment. Currently, gold nanoparticle synthesis is performed via the hot injection technique which has large variability in final particle size and a longer reaction time. One underdeveloped area by which these particles could be produced is through microwave synthesis. To initiate heating, microwaves agitate polar molecules creating a vibration that gives off the heat energy needed. Previous studies have used microwaves for gold nanoparticle synthesis; however, polar solvents were used that partially absorbed incident microwaves, leading to partial thermal heating of the sample rather than taking full advantage of the microwave to solely heat the gold nanoparticle precursors in a non-polar solution. Through this project, microwaves were utilized as the sole heat source, and non-polar solvents were used to explore the effects of microwave heating only as pertains to the precursor material. Our findings show that the use of non-polar solvents allows for more rapid heating as compared to polar solvents, and a reduction in reaction time from 10 minutes to 1 minute; this maximizes the efficiency of the reaction, and allows for reproducibility in the size/shape of the fabricated nanoparticles.

  15. Phase 2 microwave concrete decontamination results

    International Nuclear Information System (INIS)

    White, T.L.; Foster, D. Jr.; Wilson, C.T.; Schaich, C.R.

    1995-01-01

    The authors report on the results of the second phase of a four-phase program at Oak Ridge National Laboratory to develop a system to decontaminate concrete using microwave energy. The microwave energy is directed at the concrete surface through the use of an optimized wave guide antenna, or applicator, and this energy rapidly heats the free water present in the interstitial spaces of the concrete matrix. The resulting steam pressure causes the surface to burst in much the same way popcorn pops in a home microwave oven. Each steam explosion removes several square centimeters of concrete surface that are collected by a highly integrated wave guide and vacuum system. The authors call this process the microwave concrete decontamination, or MCD, process. In the first phase of the program the principle of microwaves concrete removal concrete surfaces was demonstrated. In these experiments, concrete slabs were placed on a translator and moved beneath a stationary microwave system. The second phase demonstrated the ability to mobilize the technology to remove the surfaces from concrete floors. Area and volume concrete removal rates of 10.4 cm 2 /s and 4.9 cm 3 /S, respectively, at 18 GHz were demonstrated. These rates are more than double those obtained in Phase 1 of the program. Deeper contamination can be removed by using a longer residence time under the applicator to create multiple explosions in the same area or by taking multiple passes over previously removed areas. Both techniques have been successfully demonstrated. Small test sections of painted and oil-soaked concrete have also been removed in a single pass. Concrete with embedded metal anchors on the surface has also been removed, although with some increased variability of removal depth. Microwave leakage should not pose any operational hazard to personnel, since the observed leakage was much less than the regulatory standard

  16. Advances in microwaves

    CERN Document Server

    Young, Leo

    1967-01-01

    Advances in Microwaves, Volume 2 focuses on the developments in microwave solid-state devices and circuits. This volume contains six chapters that also describe the design and applications of diplexers and multiplexers. The first chapter deals with the parameters of the tunnel diode, oscillators, amplifiers and frequency converter, followed by a simple physical description and the basic operating principles of the solid state devices currently capable of generating coherent microwave power, including transistors, harmonic generators, and tunnel, avalanche transit time, and diodes. The next ch

  17. Advances in microwaves 4

    CERN Document Server

    Young, Leo

    2013-01-01

    Advances in Microwaves, Volume 4 covers some innovations in the devices and applications of microwaves. This volume contains three chapters and begins with a discussion of the application of microwave phasers and time delay elements as beam steering elements in array radars. The next chapter provides first an overview of the technical aspects and different types of millimeter waveguides, followed by a survey of their application to railroads. The last chapter examines the general mode of conversion properties of nonuniform waveguides, such as waveguide tapers, using converted Maxwell's equatio

  18. High temperature superconducting YBCO microwave filters

    Science.gov (United States)

    Aghabagheri, S.; Rasti, M.; Mohammadizadeh, M. R.; Kameli, P.; Salamati, H.; Mohammadpour-Aghdam, K.; Faraji-Dana, R.

    2018-06-01

    Epitaxial thin films of YBCO high temperature superconductor are widely used in telecommunication technology such as microwave filter, antenna, coupler and etc., due to their lower surface resistance and lower microwave loss than their normal conductor counterparts. Thin films of YBCO were fabricated by PLD technique on LAO substrate. Transition temperature and width were 88 K and 3 K, respectively. A filter pattern was designed and implemented by wet photolithography method on the films. Characterization of the filter at 77 K has been compared with the simulation results and the results for a made gold filter. Both YBCO and gold filters show high microwave loss. For YBCO filter, the reason may be due to the improper contacts on the feedlines and for gold filter, low thickness of the gold film has caused the loss increased.

  19. Microwave multiplex readout for superconducting sensors

    Energy Technology Data Exchange (ETDEWEB)

    Ferri, E., E-mail: elena.ferri@mib.infn.it [Università Milano-Bicocca, Milan (Italy); INFN Sez. di Milano-Bicocca, Milan (Italy); Becker, D.; Bennett, D. [NIST, Boulder, CO (United States); Faverzani, M. [Università Milano-Bicocca, Milan (Italy); INFN Sez. di Milano-Bicocca, Milan (Italy); Fowler, J.; Gard, J. [NIST, Boulder, CO (United States); Giachero, A. [Università Milano-Bicocca, Milan (Italy); INFN Sez. di Milano-Bicocca, Milan (Italy); Hays-Wehle, J.; Hilton, G. [NIST, Boulder, CO (United States); Maino, M. [Università Milano-Bicocca, Milan (Italy); INFN Sez. di Milano-Bicocca, Milan (Italy); Mates, J. [NIST, Boulder, CO (United States); Puiu, A.; Nucciotti, A. [Università Milano-Bicocca, Milan (Italy); INFN Sez. di Milano-Bicocca, Milan (Italy); Reintsema, C.; Schmidt, D.; Swetz, D.; Ullom, J.; Vale, L. [NIST, Boulder, CO (United States)

    2016-07-11

    The absolute neutrino mass scale is still an outstanding challenge in both particle physics and cosmology. The calorimetric measurement of the energy released in a nuclear beta decay is a powerful tool to determine the effective electron-neutrino mass. In the last years, the progress on low temperature detector technologies has allowed to design large scale experiments aiming at pushing down the sensitivity on the neutrino mass below 1 eV. Even with outstanding performances in both energy (~ eV on keV) and time resolution (~ 1 μs) on the single channel, a large number of detectors working in parallel is required to reach a sub-eV sensitivity. Microwave frequency domain readout is the best available technique to readout large array of low temperature detectors, such as Transition Edge Sensors (TESs) or Microwave Kinetic Inductance Detectors (MKIDs). In this way a multiplex factor of the order of thousands can be reached, limited only by the bandwidth of the available commercial fast digitizers. This microwave multiplexing system will be used to readout the HOLMES detectors, an array of 1000 microcalorimeters based on TES sensors in which the {sup 163}Ho will be implanted. HOLMES is a new experiment for measuring the electron neutrino mass by means of the electron capture (EC) decay of {sup 163}Ho. We present here the microwave frequency multiplex which will be used in the HOLMES experiment and the microwave frequency multiplex used to readout the MKID detectors developed in Milan as well.

  20. Effects of Microwave Radiation on Oil Recovery

    Science.gov (United States)

    Esmaeili, Abdollah

    2011-12-01

    A variety of oil recovery methods have been developed and applied to mature and depleted reservoirs in order to improve the efficiency. Microwave radiation oil recovery method is a relatively new method and has been of great interest in the recent years. Crude oil is typically co-mingled with suspended solids and water. To increase oil recovery, it is necessary to remove these components. The separation of oil from water and solids using gravitational settling methods is typically incomplete. Oil-in-water and oil-water-solid emulsions can be demulsified and separated into their individual layers by microwave radiation. The data also show that microwave separation is faster than gravity separation and can be faster than conventional heating at many conditions. After separation of emulsion into water and oil layers, water can be discharged and oil is collected. High-frequency microwave recycling process can recover oil and gases from oil shale, residual oil, drill cuttings, tar sands oil, contaminated dredge/sediments, tires and plastics with significantly greater yields and lower costs than are available utilizing existing known technologies. This process is environmentally friendly, fuel-generating recycler to reduce waste, cut emissions, and save energy. This paper presents a critical review of Microwave radiation method for oil recovery.

  1. Handbook on dielectric and thermal properties of microwaveable materials

    CERN Document Server

    Komarov, Vyacheslav V

    2012-01-01

    The application of microwave energy for thermal processing of different materials and substances is a rapidly growing trend in modern science and engineering. In fact, optimal design work involving microwaves is impossible without solid knowledge of the properties of these materials. Here s a practical reference that collects essential data on the dielectric and thermal properties of microwaveable materials, saving you countless hours on projects in a wide range of areas, including microwave design and heating, applied electrodynamics, food science, and medical technology. This unique book provides hard-to-find information on complex dielectric permittivity of media at industrial, scientific, and medical frequencies (430 MHz, 915MHz, 2.45GHz, 5.8 GHz, and 24.125GHz). Written by a leading expert in the field, this authoritative book does an exceptional job at presenting critical data on various materials and explaining what their key characteristics are concerning microwaves.

  2. Microwave photonics shines

    Science.gov (United States)

    Won, Rachel

    2011-12-01

    The combination of microwave photonics and optics has advanced many applications in defence, wireless communications, imaging and network infrastructure. Rachel Won talks to Jianping Yao from the University of Ottawa in Canada about the importance of this growing field.

  3. Cosmic microwave background radiation

    International Nuclear Information System (INIS)

    Wilson, R.W.

    1979-01-01

    The 20-ft horn-reflector antenna at Bell Laboratories is discussed in detail with emphasis on the 7.35 cm radiometer. The circumstances leading to the detection of the cosmic microwave background radiation are explored

  4. Microwave system engineering principles

    CERN Document Server

    Raff, Samuel J

    1977-01-01

    Microwave System Engineering Principles focuses on the calculus, differential equations, and transforms of microwave systems. This book discusses the basic nature and principles that can be derived from thermal noise; statistical concepts and binomial distribution; incoherent signal processing; basic properties of antennas; and beam widths and useful approximations. The fundamentals of propagation; LaPlace's Equation and Transmission Line (TEM) waves; interfaces between homogeneous media; modulation, bandwidth, and noise; and communications satellites are also deliberated in this text. This bo

  5. A microwave powered sensor assembly for microwave ovens

    DEFF Research Database (Denmark)

    2016-01-01

    The present invention relates to a microwave powered sensor assembly for micro- wave ovens. The microwave powered sensor assembly comprises a microwave antenna for generating an RF antenna signal in response to microwave radiation at a predetermined excitation frequency. A dc power supply circuit...... of the microwave powered sensor assembly is operatively coupled to the RF antenna signal for extracting energy from the RF antenna signal and produce a power supply voltage. A sensor is connected to the power supply voltage and configured to measure a physical or chemical property of a food item under heating...... in a microwave oven chamber....

  6. Scaling up the microwave firing of ceramics

    International Nuclear Information System (INIS)

    Wroe, F.C.R.

    1993-01-01

    EA Technology, through a comprehensive R ampersand D program, is developing new microwave furnace technology focused on the ceramics processing industries. Using a combination of computer modelling, experimentation and feasibility studies, EA Technology has developed processes and procedures for firing large ceramic components. The aim of this work is to describe the investigation of the firing of ceramic products such as bricks, pottery, refractories, and industrial ceramics, using advanced processing techniques to produce and maintain uniformity of temperature throughout the components and kiln environment. This has achieved the goal of producing uniform microstructures and low thermal stress by careful control of the firing cycle. This paper illustrates the feasibility of microwave-assisted firing and shows it to be economically viable in terms of energy costs and process control. 6 refs., 1 fig

  7. Microwave-induced torrefaction of rice husk and sugarcane residues

    International Nuclear Information System (INIS)

    Wang, M.J.; Huang, Y.F.; Chiueh, P.T.; Kuan, W.H.; Lo, S.L.

    2012-01-01

    This study utilized microwave irradiation to induce torrefaction (mild pyrolysis) of rice husk and sugarcane residues by varying different parameters, including microwave power level, processing time, water content, and particle size of biomass. Proper microwave power levels are suggested to be set between 250 and 300 W for the torrefaction of these two agricultural residues. With proper processing time, the caloric value can increase 26% for rice husk and 57% for sugarcane residue. Compared to dry rice husk, both maximum reaction temperature and mass reduction ratio increased with higher water content (not over 10%). Moreover, the particle size of biomass needs not to be very small. The mass reduction ratios were 65 wt.%, 69 wt.%, and 72 wt.%, when the sizes were 50/100 mesh, 100/200 mesh, and >200 mesh, respectively. Microwave-induced torrefaction reduces more oxygen/carbon ratio of biomass in comparison with traditional torrefaction. Microwave-induced torrefaction is considered as an efficient and promising technology with great potential. -- Highlights: ► Microwave-induced torrefaction is promising compared to conventional methods. ► Neither high microwave power nor small particle size is needed. ► High energy yield can be met under mild microwave power. ► Caloric value can increase up to about 60%.

  8. Microwaves in organic chemistry and organic chemical

    Directory of Open Access Journals (Sweden)

    Mijin Dušan Ž.

    2005-01-01

    Full Text Available The usual way of applying heat to a chemical reaction is the use of a Bunsen burner, an oil or some other type of bath, or an electric heater. In inorganic chemistry, microwave technology has been used since the late 1970s while it has been implemented in organic chemistry since the mid-1980s. Microwave heating has been used in the food industry for almost fifty years. The shorter reaction times and expanded reaction range that is offered by microwave technology are suited to the increased demands in industry. For example, there is a requirement in the pharmaceutical industry for a higher number of a novel chemical entities to be produced, which requires chemists to employ a number of resources to reduce time for the production of compounds. Also, microwaves are used in the food industry, as well as in the pyrolysis of waste materials, sample preparation, the solvent extraction of natural products and the hydrolysis of proteins and peptides.

  9. Microwave imaging for plasma diagnostics and its applications

    International Nuclear Information System (INIS)

    Mase, A.; Kogi, Y.; Ito, N.

    2007-01-01

    Microwave to millimeter-wave diagnostic techniques such as interferometry, reflectometry, scattering, and radiometry have been powerful tools for diagnosing magnetically confined plasmas. Important plasma parameters were measured to clarify the physics issues such as stability, wave phenomena, and fluctuation-induced transport. Recent advances in microwave and millimeter-wave technology together with computer technology have enabled the development of advanced diagnostics for visualization of 2D and 3D structures of plasmas. Microwave/millimeter-wave imaging is expected to be one of the most promising diagnostic methods for this purpose. We report here on the representative microwave diagnostics and their industrial applications as well as application to magnetically-confined plasmas. (author)

  10. Design of a microwave calorimeter for the microwave tokamak experiment

    International Nuclear Information System (INIS)

    Marinak, M.

    1988-01-01

    The initial design of a microwave calorimeter for the Microwave Tokamak Experiment is presented. The design is optimized to measure the refraction and absorption of millimeter rf microwaves as they traverse the toroidal plasma of the Alcator C tokamak. Techniques utilized can be adapted for use in measuring high intensity pulsed output from a microwave device in an environment of ultra high vacuum, intense fields of ionizing and non-ionizing radiation and intense magnetic fields. 16 refs

  11. Hybrid Microwave Treatment of SRS TRU and Mixed Wastes

    International Nuclear Information System (INIS)

    Wicks, G.G.

    1999-01-01

    A new process, using hybrid microwave energy, has been developed as part of the Strategic Research and Development program and successfully applied to treatment of a wide variety of non-radioactive materials, representative of SRS transuranic (TRU) and mixed wastes. Over 35 simulated (non-radioactive) TRU and mixed waste materials were processed individually, as well as in mixed batches, using hybrid microwave energy, a new technology now being patented by Westinghouse Savannah River Company (WSRC)

  12. Carbon Fiber TOW Angle Determination Using Microwave Reflectometry

    Science.gov (United States)

    Wilson, William C.; Moore, Jason P.; Juarez, Peter D.

    2016-01-01

    NASA's Advanced Composites Project is investigating technologies that increase automated remote inspection of aircraft composite structures. Therefore, microwave Frequency Domain Reflectometry (FDR) is being investigated as a method of enabling rapid remote inspection of angular orientation of the tow using microwave radiation. This work will present preliminary data demonstrating that frequency shifts in the reflection spectrum of a carbon fiber tow sample are indicative of the angle of the tow with respect to an interrogating antenna's linear polarized output.

  13. Microwave engineering concepts and fundamentals

    CERN Document Server

    Khan, Ahmad Shahid

    2014-01-01

    Detailing the active and passive aspects of microwaves, Microwave Engineering: Concepts and Fundamentals covers everything from wave propagation to reflection and refraction, guided waves, and transmission lines, providing a comprehensive understanding of the underlying principles at the core of microwave engineering. This encyclopedic text not only encompasses nearly all facets of microwave engineering, but also gives all topics—including microwave generation, measurement, and processing—equal emphasis. Packed with illustrations to aid in comprehension, the book: •Describes the mathematical theory of waveguides and ferrite devices, devoting an entire chapter to the Smith chart and its applications •Discusses different types of microwave components, antennas, tubes, transistors, diodes, and parametric devices •Examines various attributes of cavity resonators, semiconductor and RF/microwave devices, and microwave integrated circuits •Addresses scattering parameters and their properties, as well a...

  14. High power microwave source development

    Science.gov (United States)

    Benford, James N.; Miller, Gabriel; Potter, Seth; Ashby, Steve; Smith, Richard R.

    1995-05-01

    The requirements of this project have been to: (1) improve and expand the sources available in the facility for testing purposes and (2) perform specific tasks under direction of the Defense Nuclear Agency about the applications of high power microwaves (HPM). In this project the HPM application was power beaming. The requirements of this program were met in the following way: (1) We demonstrated that a compact linear induction accelerator can drive HPM sources at repetition rates in excess of 100 HZ at peak microwave powers of a GW. This was done for the relativistic magnetron. Since the conclusion of this contract such specifications have also been demonstrated for the relativistic klystron under Ballistic Missile Defense Organization funding. (2) We demonstrated an L band relativistic magnetron. This device has been used both on our single pulse machines, CAMEL and CAMEL X, and the repetitive system CLIA. (3) We demonstrated that phase locking of sources together in large numbers is a feasible technology and showed the generation of multigigawatt S-band radiation in an array of relativistic magnetrons.

  15. Development of FR fuel cycle in Japan (3) - Current state on unified technology of De-nitration conversion and granulation for the simplified pellet fuel production based on microwave heating

    International Nuclear Information System (INIS)

    Suzuki, M.; Ishii, K.; Yamamoto, T.; Kato, Y.; Kurita, T.; Yoshimoto, K.; Kihara, Y.; Namekawa, T.; Fujii, K. I.

    2008-01-01

    The major experimental results and current state on unified and simplified de-nitration conversion processing are explained. This technology was enabled by the nitrate solutions mixing method which is our original idea proposed in FS phase II project and transferred to present FaCT project where the mass production is the supreme subject. The major results obtained up to present, which are based on the two originalities, are as follows; (1) The mixing rate of the plutonium nitrate solution (PNS) into the uranium nitrate solution (UNS) was satisfactorily adjusted by the feeding of 0.5 litter step, (2) Excellent size uniformity around 10 μm was obtained in the MOX powders including 30 wt% of PUO 2 products, (3) In the microwave heating, a mild and stable boiling occurred at whole space in the evaporation dish and the size of bubbles gradually became smaller closing to the finishing stage, (4) The Can coefficient of raw MOX powders containing 30 wt% of PUO 2 was ranged 20-40 just before granulation, being rather difficult to pack them in a die, but after the granulation, the packing rate reached 100 %. (authors)

  16. Parameter prediction for microwave garnets

    International Nuclear Information System (INIS)

    Ramer, R.

    1996-01-01

    Full text: Linearity of the microwave parameters (resonance linewidth ΔH and effective linewidth ΔH eff ) is demonstrated and their use in the Computer-aided design (CAD)/Computer-aided manufacturing (CAM) of new microwave garnets is proposed. Such an approach would combine a numerical database of microwave data and several computational programs. The model is an applied formulation of the analysis of a wide range of microwave garnets

  17. High power microwaves

    CERN Document Server

    Benford, James; Schamiloglu, Edl

    2016-01-01

    Following in the footsteps of its popular predecessors, High Power Microwaves, Third Edition continues to provide a wide-angle, integrated view of the field of high power microwaves (HPMs). This third edition includes significant updates in every chapter as well as a new chapter on beamless systems that covers nonlinear transmission lines. Written by an experimentalist, a theorist, and an applied theorist, respectively, the book offers complementary perspectives on different source types. The authors address: * How HPM relates historically and technically to the conventional microwave field * The possible applications for HPM and the key criteria that HPM devices have to meet in order to be applied * How high power sources work, including their performance capabilities and limitations * The broad fundamental issues to be addressed in the future for a wide variety of source types The book is accessible to several audiences. Researchers currently in the field can widen their understanding of HPM. Present or pot...

  18. Microwave-assisted Chemical Transformations

    Science.gov (United States)

    In recent years, there has been a considerable interest in developing sustainable chemistries utilizing green chemistry principles. Since the first published report in 1986 by Gedye and Giguere on microwave assisted synthesis in household microwave ovens, the use of microwaves as...

  19. Microwave integrated circuits for space applications

    Science.gov (United States)

    Leonard, Regis F.; Romanofsky, Robert R.

    1991-01-01

    Monolithic microwave integrated circuits (MMIC), which incorporate all the elements of a microwave circuit on a single semiconductor substrate, offer the potential for drastic reductions in circuit weight and volume and increased reliability, all of which make many new concepts in electronic circuitry for space applications feasible, including phased array antennas. NASA has undertaken an extensive program aimed at development of MMICs for space applications. The first such circuits targeted for development were an extension of work in hybrid (discrete component) technology in support of the Advanced Communication Technology Satellite (ACTS). It focused on power amplifiers, receivers, and switches at ACTS frequencies. More recent work, however, focused on frequencies appropriate for other NASA programs and emphasizes advanced materials in an effort to enhance efficiency, power handling capability, and frequency of operation or noise figure to meet the requirements of space systems.

  20. Microwave Assisted Drug Delivery

    DEFF Research Database (Denmark)

    Jónasson, Sævar Þór; Zhurbenko, Vitaliy; Johansen, Tom Keinicke

    2014-01-01

    In this work, the microwave radiation is adopted for remote activation of pharmaceutical drug capsules inside the human body in order to release drugs at a pre-determined time and location. An array of controllable transmitting sources is used to produce a constructive interference at a certain...... focus point inside the body, where the drugs are then released from the specially designed capsules. An experimental setup for microwave activation has been developed and tested on a body phantom that emulates the human torso. A design of sensitive receiving structures for integration with a drug...

  1. Compact microwave ion source

    International Nuclear Information System (INIS)

    Leung, K.N.; Walther, S.; Owren, H.W.

    1985-05-01

    A small microwave ion source has been fabricated from a quartz tube with one end enclosed by a two grid accelerator. The source is also enclosed by a cavity operated at a frequency of 2.45 GHz. Microwave power as high as 500 W can be coupled to the source plasma. The source has been operated with and without multicusp fields for different gases. In the case of hydrogen, ion current density of 200 mA/cm -2 with atomic ion species concentration as high as 80% has been extracted from the source

  2. Microwave circulator design

    CERN Document Server

    Linkhart, Douglas K

    2014-01-01

    Circulator design has advanced significantly since the first edition of this book was published 25 years ago. The objective of this second edition is to present theory, information, and design procedures that will enable microwave engineers and technicians to design and build circulators successfully. This resource contains a discussion of the various units used in the circulator design computations, as well as covers the theory of operation. This book presents numerous applications, giving microwave engineers new ideas about how to solve problems using circulators. Design examples are provided, which demonstrate how to apply the information to real-world design tasks.

  3. Environmental assessment for the Satellite Power System (SPS) Concept Development and Evaluation Program (CDEP). [Microwave and non-microwave health and ecological assessment

    Energy Technology Data Exchange (ETDEWEB)

    Valentino, A.R.

    1980-08-01

    In the satellite power system (SPS), satellites in geosynchronous earth orbit would collect solar energy in space, convert it to microwaves, and transmit the microwaves to receiving antennas (rectennas) on earth. At the rectennas, the microwave energy would be converted to electricity. This SPS environmental assessment considers the microwave and nonmicrowave effects on the terrestrial environment and human health, atmospheric effects, and effects on electromagnetic systems. No environmental problem has been identified that would preclude the continued study of SPS technology. To increase the certainty of the assessment, some research has been initiated and long-term research is being planned.

  4. Microwave Photonics: current challenges towards widespread application.

    Science.gov (United States)

    Capmany, José; Li, Guifang; Lim, Christina; Yao, Jianping

    2013-09-23

    Microwave Photonics, a symbiotic field of research that brings together the worlds of optics and radio frequency is currently facing several challenges in its transition from a niche to a truly widespread technology essential to support the ever-increasing values for speed, bandwidth, processing capability and dynamic range that will be required in next generation hybrid access networks. We outline these challenges, which are the subject of the contributions to this focus issue.

  5. Electromagnetic and thermal history during microwave heating

    International Nuclear Information System (INIS)

    Santos, T.; Valente, M.A.; Monteiro, J.; Sousa, J.; Costa, L.C.

    2011-01-01

    In microwave heating, the energy is directly introduced into the material resulting in a rapid and volumetric heating process with reduced thermal gradients, when the electromagnetic field is homogeneous. From those reasons, the microwave technology has been widely used in the industry to process dielectric materials. The capacity to heat with microwave radiation is related with the dielectric properties of the materials and the electromagnetic field distribution. The knowledge of the permittivity dependence with the temperature is essential to understand the thermal distribution and to minimize the non-homogeneity of the electromagnetic field. To analyse the history of the heating process, the evolution of the electromagnetic field, the temperature and the skin depth, were simulated dynamically in a ceramic sample. The evaluation of the thermal runaway has also been made. This is the most critical phenomenon observed in the sintering of ceramic materials because it causes deformations, or even melting on certain points in the material, originating the destruction of it. In our study we show that during the heating process the hot spot's have some dynamic, and at high temperatures most of the microwave energy is absorbed at the surface of the material. We also show the existence of a time-delay of the thermal response with the electromagnetic changes. - Highlights: → Electromagnetic field, the temperature and the skin depth were simulated dynamically. → The evaluation of the thermal runaway has been made. → A time-delay of the thermal response with the electromagnetic changes exists.

  6. Analysis of mixed mode microwave distribution manifolds

    International Nuclear Information System (INIS)

    White, T.L.

    1982-09-01

    The 28-GHz microwave distribution manifold used in the ELMO Bumpy Torus-Scale (EBT-S) experiments consists of a toroidal metallic cavity, whose dimensions are much greater than a wavelength, fed by a source of microwave power. Equalization of the mixed mode power distribution ot the 24 cavities of EBT-S is accomplished by empirically adjusting the coupling irises which are equally spaced around the manifold. The performance of the manifold to date has been very good, yet no analytical models exist for optimizing manifold transmission efficiency or for scaling this technology to the EBT-P manifold design. The present report develops a general model for mixed mode microwave distribution manifolds based on isotropic plane wave sources of varying amplitudes that are distributed toroidally around the manifold. The calculated manifold transmission efficiency for the most recent EBT-S coupling iris modification is 90%. This agrees with the average measured transmission efficiency. Also, the model predicts the coupling iris areas required to balance the distribution of microwave power while maximizing transmission efficiency, and losses in waveguide feeds connecting the irises to the cavities of EBT are calculated using an approach similar to the calculation of mainfold losses. The model will be used to evaluate EBT-P manifold designs

  7. Microwave wood strand drying: energy consumption, VOC emission and drying quality

    Energy Technology Data Exchange (ETDEWEB)

    Wang, S.; Du, G.; Zhang, Y. [Tennessee Univ., Knoxville, TN (United States). Dept. of Forestry, Wildlife and Fisheries

    2005-07-01

    The objective of this research was to develop microwave drying technology for wood strand drying for oriented strand board (OSB) manufacturing. The advantages of microwave drying included a reduction in the drying time of wood strands and a reduction in the release of volatile organic compounds (VOC) through a decrease in the thermal degradation of the wood material. Temperature and moisture content changes under different microwave drying conditions were investigated. The effects of microwave drying on VOC emissions were evaluated and analyzed using gas chromatography and mass spectrometry. Microwave power input and the mass of drying materials in the microwave oven were found to have a dominant effect on drying quality. Results indicated that an increase in microwave power input and a decrease in sample weights resulted in high drying temperatures, short drying times and a high drying rate. The effect of microwave drying on the strand surfaces was also investigated. Different strand geometries and initial moisture content resulted in varying warm-up curves, but did not influence final moisture content. VOC emissions were quantified by comparing alpha-pinene concentrations. The microwave drying resulted in lower VOC emissions compared with conventional drying methods. It was concluded that the microwave drying technique provided faster strand drying and reduced energy consumption by up to 50 per cent. In addition, the surface wettability of wood strands dried with microwaves was better than with an industrial rotary drum drier. 12 refs., 3 tabs., 5 figs.

  8. Heat transfer within a concrete slab applying the microwave decontamination process

    International Nuclear Information System (INIS)

    Li, W.; Ebadian, M.A.; White, T.L.; Grubb, R.G.

    1993-01-01

    Decontamination of a radioactive contaminated concrete surface is a new technology for the treatment of radioactive waste. In this paper, concrete decontamination using microwave technology is investigated theoretically. A plane wave assumption of microwave propagation has been employed to estimate the microwave field and power dissipation within the concrete. A one-dimensional, unsteady heat conduction model with microwave heat dissipation resulting from microwave-material interaction has been used to evaluate frequency, steel reinforcement within the concrete, and thermal boundary conditions are also considered in the present model. Four commonly used microwave frequencies of 0.896, 2.45, 10.6, and 18.0 GHz have been utilized in the analysis. The results revealed that as the microwave frequency increases to, or higher than 10.6 GHz, the microwave power dissipation shifts toward the front surface of the concrete. Furthermore, it was observed that use of a higher frequency microwave could reduce power intensity requirements needed to raise the temperature difference or thermal stress to the same value in the same period of time. It was found that the presence of reinforcing steel mesh causes part of the microwave energy to be blocked and reflected. Thus, the temperature or thermal stress of the concrete increases before the reinforcement, and decreases after the reinforcement. 16 refs., 6 figs., 3 tabs

  9. [Study on the emission spectrum of microwave plasma in liquid].

    Science.gov (United States)

    Wang, Bo; Sun, Bing; Zhu, Xiao-Mei; Yan, Zhi-Yu; Liu, Yong-Jun; Liu, Hui

    2014-05-01

    After the technology of microwave discharge in liquid is realized for the first time in China, the basic physical phenomena and characteristic of microwave discharge in liquid is studied in order to lay a theoretical foundation of research on microwave discharge in liquid. In the present paper, the active particles generated by microwave discharge in liquid were detected using the emission spectrometer, and the statistical method of spectrum data of microwave discharge in liquid was also studied. The emission spectrometer and numerically controlled camera were used to detect synchronously the process of the initial discharge and stable discharge of microwave discharge in liquid. The results show that: the emission intensity of microwave plasma in liquid has a large fluctuation, and the spectrum intensity can be calculated using the average of 10 spectrum data points. The intensity of discharge is reflected by the plasma area in a certain extent, however, the variation gradient of the intensity of discharge is different from that of the plasma area. This is mainly because that, in the process of discharging, the discharge intensity is not only reflected by the plasma area, but also reflected by the brightness of the plasma.

  10. Blueprint for a microwave trapped-ion quantum computer

    DEFF Research Database (Denmark)

    Lekitsch, B.; Weidt, S.; Fowler, A. G.

    2017-01-01

    , are constructed using silicon microfabrication techniques and they are within reach of current technology. To perform the required quantum computations, the modules make use of long-wavelength-radiation based quantum gate technology. To scale this microwave quantum computer architecture to an arbitrary size we...

  11. Microwave stability at transition

    International Nuclear Information System (INIS)

    Holt, J.A.; Colestock, P.L.

    1995-05-01

    The question of microwave stability at transition is revisited using a Vlasov approach retaining higher order terms in the particle dynamics near the transition energy. A dispersion relation is derived which can be solved numerically for the complex frequency in terms of the longitudinal impedance and other beam parameters. Stability near transition is examined and compared with simulation results

  12. Leakage of Microwave Ovens

    Science.gov (United States)

    Abdul-Razzaq, W.; Bushey, R.; Winn, G.

    2011-01-01

    Physics is essential for students who want to succeed in science and engineering. Excitement and interest in the content matter contribute to enhancing this success. We have developed a laboratory experiment that takes advantage of microwave ovens to demonstrate important physical concepts and increase interest in physics. This experiment…

  13. Open microwave cavities

    Czech Academy of Sciences Publication Activity Database

    Šeba, Petr; Rotter, I.; Mueller, M.; Persson, C.; Pichugin, Konstantin N.

    2001-01-01

    Roč. 9, - (2001), s. 484-487 ISSN 1386-9477 Institutional research plan: CEZ:A02/98:Z1-010-914 Keywords : microwave cavity * resonances Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.009, year: 2001

  14. New applications of microwave

    International Nuclear Information System (INIS)

    Ejiri, A.; Tanaka, K.; Kawahata, K.; Ito, Y.; Tokuzawa, T.

    2000-01-01

    Interferometry and reflectometry measure phase of the transparent or the reflected wave to derive the information on plasma density. Homodyne reflectometry for an interlock and transmissiometry for sheet plasma measurements could be another class of microwave diagnostics, which does not measure the phase. (author)

  15. Vitrification of radioactive contaminated soil by means of microwave energy

    Science.gov (United States)

    Yuan, Xun; Qing, Qi; Zhang, Shuai; Lu, Xirui

    2017-03-01

    Simulated radioactive contaminated soil was successfully vitrified by microwave sintering technology and the solidified body were systematically studied by Raman, XRD and SEM-EDX. The Raman results show that the solidified body transformed to amorphous structure better at higher temperature (1200 °C). The XRD results show that the metamictization has been significantly enhanced by the prolonged holding time at 1200 °C by microwave sintering, while by conventional sintering technology other crystal diffraction peaks, besides of silica at 2θ = 27.830°, still exist after being treated at 1200 °C for much longer time. The SEM-EDX discloses the micro-morphology of the sample and the uniform distribution of Nd element. All the results show that microwave technology performs vitrification better than the conventional sintering method in solidifying radioactive contaminated soil.

  16. RF microwave circuit design for wireless applications

    CERN Document Server

    Rohde, Ulrich L

    2012-01-01

    Provides researchers and engineers with a complete set of modeling, design, and implementation tools for tackling the newest IC technologies Revised and completely updated, RF/Microwave Circuit Design for Wireless Applications, Second Edition is a unique, state-of-the-art guide to wireless integrated circuit design that provides researchers and engineers with a complete set of modeling, design, and implementation tools for tackling even the newest IC technologies. It emphasizes practical design solutions for high-performance devices and circuitry, incorporating ample exa

  17. Highly efficient isocyanate-free microwave-assisted synthesis of [6]-oligourea

    KAUST Repository

    Qaroush, Abdussalam K.; Al-Hamayda, Asmaa S.; Khashman, Yasmeen K.; Vagin, Sergei I.; Troll, Carsten; Rieger, Bernhard

    2013-01-01

    data reported are reproducible (due to the homogeneous microwave technology used by CEM Discover S-Class of microwave reactors). To the best of our knowledge, this is the best eco-friendly synthetic approach for the preparation of the title oligomers

  18. Microwave heating processing as alternative of pretreatment in second-generation biorefinery: An overview

    International Nuclear Information System (INIS)

    Aguilar-Reynosa, Alejandra; Romaní, Aloia; Rodríguez-Jasso, Rosa Ma.; Aguilar, Cristóbal N.; Garrote, Gil; Ruiz, Héctor A.

    2017-01-01

    Highlights: • Microwave heating pretreatment for lignocellulosic material. • Fundament of lignocellulosic material fractionation using microwave irradiation. • Energy consumption in microwave pretreatments and microwave reactors description. • Microwave heating as pretreatment in a biorefinery concept. - Abstract: The development of a feasible biorefinery is in need of alternative technologies to improve lignocellulosic biomass conversion by the suitable use of energy. Microwave heating processing (MHP) is emerging as promising unconventional pretreatment of lignocellulosic materials (LCMs). MHP applied as pretreatment induces LCMs breakdown through the molecular collision caused by the dielectric polarization. Polar particles movement generates a quick heating consequently the temperatures and times of process are lower. In this way, MHP has positioned as green technology in comparison with other types of heating. Microwave technology represents an excellent option to obtain susceptible substrates to enzymatic saccharification and subsequently in the production of bioethanol and high-added compounds. However, it is still necessary to study the dielectric properties of materials, and conduct economic studies to achieve development in pilot and industrial scale. This work aims to provide an overview of recent progress and alternative configurations for combining the application of microwave technology on the pretreatment of LCMs in terms of biorefinery.

  19. RESEARCH OF MICROWAVE'S INFLUENCE ON QUALITY OF DELICIOUS PRODUCTS FROM BEEF

    Directory of Open Access Journals (Sweden)

    T. Kozlova

    2012-03-01

    Full Text Available Influence of time of microwave fluctuations on organoleptic indicators, chemical composition, exit and periods of storage of a meat product is investigated. It is established that the use of microwave technology in the beef delicacy reduces the salting by 3 times, and baking by 1,2 times. The yield of finished products increased by 2 times.

  20. Microwave plasmas generated in bubbles immersed in liquids for hydrocarbons reforming

    International Nuclear Information System (INIS)

    Levko, Dmitry; Sharma, Ashish; Raja, Laxminarayan L

    2016-01-01

    We present a computational modeling study of microwave plasma generated in cluster of atmospheric-pressure argon bubbles immersed in a liquid. We demonstrate that the use of microwaves allows the generation of a dense chemically active non-equilibrium plasma along the gas–liquid interface. Also, microwaves allow generation of overdense plasma in all the bubbles considered in the cluster which is possible because the collisional skin depth of the wave exceeds the bubble dimension. These features of microwave plasma generation in bubbles immersed in liquids are highly desirable for the large-scale liquid hydrocarbon reforming technologies. (letter)

  1. Microwave superheaters for fusion

    International Nuclear Information System (INIS)

    Campbell, R.B.; Hoffman, M.A.; Logan, B.G.

    1987-01-01

    The microwave superheater uses the synchrotron radiation from a thermonuclear plasma to heat gas seeded with an alkali metal to temperatures far above the temperature of material walls. It can improve the efficiency of the Compact Fusion Advanced Rankine (CFAR) cycle described elsewhere in these proceedings. For a proof-of-principle experiment using helium, calculations show that a gas superheat ΔT of 2000 0 K is possible when the wall temperature is maintained at 1000 0 K. The concept can be scaled to reactor grade systems. Because of the need for synchrotron radiation, the microwave superheater is best suited for use with plasmas burning an advanced fuel such as D- 3 He. 5 refs

  2. The Cosmic Microwave Background

    Directory of Open Access Journals (Sweden)

    Jones Aled

    1998-01-01

    Full Text Available We present a brief review of current theory and observations of the cosmic microwave background (CMB. New predictions for cosmological defect theories and an overview of the inflationary theory are discussed. Recent results from various observations of the anisotropies of the microwave background are described and a summary of the proposed experiments is presented. A new analysis technique based on Bayesian statistics that can be used to reconstruct the underlying sky fluctuations is summarised. Current CMB data is used to set some preliminary constraints on the values of fundamental cosmological parameters $Omega$ and $H_circ$ using the maximum likelihood technique. In addition, secondary anisotropies due to the Sunyaev-Zel'dovich effect are described.

  3. Thermoactivation of viruses by microwaves

    Energy Technology Data Exchange (ETDEWEB)

    Mahnel, H.; von Brodorotti, H.S.

    1981-01-01

    Eight different viruses, suspended in drinking water, were examined for their ability to be inactivated by microwaves from a microwave oven. Up to a virus content of 10/sup 5/ TCID/sub 50//ml inactivation was successful within a few minutes of microwave treatment and occurred in parallel to the heat stability of the viruses. Evidence for direct effects of microwaves on viruses could not be detected. 7 of the viruses studied were inactivated rapidly when temperatures of 50 to 65/sup 0/C under microwave treatment were reached in the flowing water, while a bovine parvovirus was only inactivated by temperatures above 90/sup 0/C. The advantages of a thermal virus-decontamination of fluids and material by microwaves are discussed.

  4. Microwave Power Beaming Infrastructure for Manned Lightcraft Operations: Part 2

    International Nuclear Information System (INIS)

    Myrabo, Leik N.

    2008-01-01

    In the past ∼7 years, microwave gyrotron technology has rapidly evolved to a critical threshold wherein ultra-energetic space launch missions based on beamed energy propulsion (BEP) now appear eminently feasible. Over the next 20 years, hundred megawatt-class microwave power-beaming stations could be prototyped on high deserts and 3- to 4 km mountain peaks before migrating into low Earth orbit, along with their passive microwave relay satellites. Described herein is a 20 GW rechargeable nuclear power satellite and microwave power-beaming infrastructure designed for manned space launch operations in the year 2025. The technological readiness of 2500 GJ superconducting magnetic energy storage 'batteries', 433-m ultralight space structures, 100 MW liquid droplet radiators, 1-6+ MW gyrotron sources, and mega-scale arrays (e.g., 3000 phase-locked units) is addressed. Microwave BEP is 'breakthrough' technology with the very real potential to radically reduce space access costs by factors of 100 to 1000 in the forseeable future

  5. Introduction to Microwave Linear [Accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Whittum, David H

    1999-01-04

    The elements of microwave linear accelerators are introduced starting with the principles of acceleration and accelerating structures. Considerations for microwave structure modeling and design are developed from an elementary point of view. Basic elements of microwave electronics are described for application to the accelerator circuit and instrumentation. Concepts of beam physics are explored together with examples of common beamline instruments. Charged particle optics and lattice diagnostics are introduced. Considerations for fixed-target and colliding-beam experimentation are summarized.

  6. Microwave-Assisted Drying for the Conservation of Honeybee Pollen

    Directory of Open Access Journals (Sweden)

    Angelo Canale

    2016-05-01

    Full Text Available Bee pollen is becoming an important product thanks to its nutritional properties, including a high content of bioactive compounds such as essential amino acids, antioxidants, and vitamins. Fresh bee pollen has a high water content (15%–30% wt %, thus it is a good substrate for microorganisms. Traditional conservation methods include drying in a hot air chamber and/or freezing. These techniques may significantly affect the pollen organoleptic properties and its content of bioactive compounds. Here, a new conservation method, microwave drying, is introduced and investigated. The method implies irradiating the fresh pollen with microwaves under vacuum, in order to reduce the water content without reaching temperatures capable of thermally deteriorating important bioactive compounds. The method was evaluated by taking into account the nutritional properties after the treatment. The analyzed parameters were phenols, flavonoids, with special reference to rutin content, and amino acids. Results showed that microwave drying offers important advantages for the conservation of bee pollen. Irrespective of microwave power and treatment time, phenol and flavonoid content did not vary over untreated fresh pollen. Similarly, rutin content was unaffected by the microwave drying, suggesting that the microwave-assisted drying could be a powerful technology to preserve bioprotective compounds in fresh pollen.

  7. The application of microwave photonic detection in quantum communication

    Science.gov (United States)

    Diao, Wenting; Zhuang, Yongyong; Song, Xuerui; Wang, Liujun; Duan, Chongdi

    2018-03-01

    Quantum communication has attracted much attention in recent years, provides an ultimate level of security, and uniquely it is one of the most likely practical quantum technologies at present. In order to realize global coverage of quantum communication networks, not only need the help of satellite to realize wide area quantum communication, need implementation of optical fiber system to realize city to city quantum communication, but also, it is necessary to implement end-to-end quantum communications intercity and wireless quantum communications that can be received by handheld devices. Because of the limitation of application of light in buildings, it needs quantum communication with microwave band to achieve quantum reception of wireless handheld devices. The single microwave photon energy is very low, it is difficult to directly detect, which become a difficulty in microwave quantum detection. This paper summarizes the mode of single microwave photon detection methods and the possibility of application in microwave quantum communication, and promotes the development of quantum communication in microwave band and quantum radar.

  8. Non-Ionizing Radiation Used in Microwave Ovens

    Science.gov (United States)

    ... Non-Ionizing Radiation Used in Microwave Ovens Non-Ionizing Radiation Used in Microwave Ovens Explore the interactive, virtual ... can do Where to learn more About Non-Ionizing Radiation Used in Microwave Ovens Microwave Oven. Microwave ovens ...

  9. A high-brightness thermionic microwave electron gun

    International Nuclear Information System (INIS)

    Borland, M.

    1991-02-01

    In a collaborative effort by SSRL, AET Associates, and Varian Associates, a high-brightness microwave electron gun using a thermionic cathode has been designed, built, tested, and installed for use with the SSRL 150 MeV linear accelerator. This thesis discusses the physics behind the design and operation of the gun and associated systems, presenting predictions and experimental tests of the gun's performance. The microwave gun concept is of increasing interest due to its promise of providing higher-current, lower-emittance electron beams than possible from conventional, DC gun technology. In a DC guns, accelerating gradients are less than 8 MV/m, while those in a microwave gun can exceed 100 MV/m, providing much more rapid initial acceleration, thereby reducing the deleterious effects of space-charge. Microwave guns produce higher momentum beams than DC guns, thus lessening space-charge effects during subsequent beam transport. Typical DC guns produce kinetic energies of 80--400 KeV, compared to 2--3 MeV for the SSRL microwave gun. ''State-of-the-art'' microwave gun designs employ laser-driven photocathodes, providing excellent performance but with greater complexity and monetary costs. A thermionic microwave gun with a magnetic bunching system is comparable in cost and complexity to a conventional system, but provides performance that is orders of magnitude better. Simulations of the SSRL microwave gun predict a normalized RMS emittance at the gun exist of e c · μm for a beam consisting of approximately 50% of the particles emitted from the gun, and having a momentum spread ±10%. These emittances are for up to 5 x 10 9 e - per bunch. Chromatic aberrations in the transport line between the gun and linear accelerator increase this to typically e · μm

  10. A high-brightness thermionic microwave electron gun

    Energy Technology Data Exchange (ETDEWEB)

    Borland, Michael [Stanford Univ., CA (United States)

    1991-02-01

    In a collaborative effort by SSRL, AET Associates, and Varian Associates, a high-brightness microwave electron gun using a thermionic cathode has been designed, built, tested, and installed for use with the SSRL 150 MeV linear accelerator. This thesis discusses the physics behind the design and operation of the gun and associated systems, presenting predictions and experimental tests of the gun`s performance. The microwave gun concept is of increasing interest due to its promise of providing higher-current, lower-emittance electron beams than possible from conventional, DC gun technology. In a DC guns, accelerating gradients are less than 8 MV/m, while those in a microwave gun can exceed 100 MV/m, providing much more rapid initial acceleration, thereby reducing the deleterious effects of space-charge. Microwave guns produce higher momentum beams than DC guns, thus lessening space-charge effects during subsequent beam transport. Typical DC guns produce kinetic energies of 80--400 KeV, compared to 2--3 MeV for the SSRL microwave gun. ``State-of-the-art`` microwave gun designs employ laser-driven photocathodes, providing excellent performance but with greater complexity and monetary costs. A thermionic microwave gun with a magnetic bunching system is comparable in cost and complexity to a conventional system, but provides performance that is orders of magnitude better. Simulations of the SSRL microwave gun predict a normalized RMS emittance at the gun exist of < 10 π • mec • μm for a beam consisting of approximately 50% of the particles emitted from the gun, and having a momentum spread ±10%. These emittances are for up to 5 x 109e- per bunch. Chromatic aberrations in the transport line between the gun and linear accelerator increase this to typically < 30 π • me • μm.

  11. A Microwave Photonic Interference Canceller: Architectures, Systems, and Integration

    Science.gov (United States)

    Chang, Matthew P.

    This thesis is a comprehensive portfolio of work on a Microwave Photonic Self-Interference Canceller (MPC), a specialized optical system designed to eliminate interference from radio-frequency (RF) receivers. The novelty and value of the microwave photonic system lies in its ability to operate over bandwidths and frequencies that are orders of magnitude larger than what is possible using existing RF technology. The work begins, in 2012, with a discrete fiber-optic microwave photonic canceller, which prior work had demonstrated as a proof-of-concept, and culminates, in 2017, with the first ever monolithically integrated microwave photonic canceller. With an eye towards practical implementation, the thesis establishes novelty through three major project thrusts. (Fig. 1): (1) Extensive RF and system analysis to develop a full understanding of how, and through what mechanisms, MPCs affect an RF receiver. The first investigations of how a microwave photonic canceller performs in an actual wireless environment and a digital radio are also presented. (2) New architectures to improve the performance and functionality of MPCs, based on the analysis performed in Thrust 1. A novel balanced microwave photonic canceller architecture is developed and experimentally demonstrated. The balanced architecture shows significant improvements in link gain, noise figure, and dynamic range. Its main advantage is its ability to suppress common-mode noise and reduce noise figure by increasing the optical power. (3) Monolithic integration of the microwave photonic canceller into a photonic integrated circuit. This thrust presents the progression of integrating individual discrete devices into their semiconductor equivalent, as well as a full functional and RF analysis of the first ever integrated microwave photonic canceller.

  12. The European Microwave Week 2008 and its Microwave Conferences

    NARCIS (Netherlands)

    Hoogeboom, P.; Van Vliet, F.

    2009-01-01

    Under the auspices of the European Microwave Association (EuMA) the 11th annual European Microwave Week was organized in the Amsterdam RAI Congress Centre, The Netherlands, 27-31 October 2008. This major event consisted this year of five conferences, an exhibition, and various side events. The 38th

  13. Production of biodiesel using the microwave technique

    Directory of Open Access Journals (Sweden)

    Shakinaz A. El Sherbiny

    2010-10-01

    Full Text Available Biodiesel production is worthy of continued study and optimization of production procedures because of its environmentally beneficial attributes and its renewable nature. Non-edible vegetable oils such as Jatropha oil, produced by seed-bearing shrubs, can provide an alternative and do not have competing food uses. However, these oils are characterized by their high free fatty acid contents. Using the conventional transesterification technique for the production of biodiesel is well established. In this study an alternative energy stimulant, “microwave irradiation”, was used for the production of the alternative energy source, biodiesel. The optimum parametric conditions obtained from the conventional technique were applied using microwave irradiation in order to compare the systems. The study showed that the application of radio frequency microwave energy offers a fast, easy route to this valuable biofuel with the advantages of enhancing the reaction rate (2 min instead of 150 min and of improving the separation process. The methodology allows for the use of high free fatty acid content feedstock, including Jatropha oil. However, this emerging technology needs to be further investigated for possible scale-up for industrial application.

  14. Microwave pulse generation by photoconductive switching

    Energy Technology Data Exchange (ETDEWEB)

    Pocha, M.D.; Druce, R.L.

    1989-03-14

    Laser activated photoconductive semiconductor switching shows significant potential for application in high power microwave generation. Primary advantages of this concept are: small size, light weight, ruggedness, precise timing and phasing by optical control, and the potential for high peak power in short pulses. Several concepts have been suggested for microwave generation using this technology. They generally fall into two categories (1) the frozen wave generator or (2) tuned cavity modulation, both of which require only fast closing switches. We have been exploring a third possibility requiring fast closing and opening switches, that is the direct modulation of the switch at microwave frequencies. Switches have been fabricated at LLNL using neutron irradiated Gallium Arsenide which exhibit response times as short as 50 ps at low voltages. We are in the process of performing high voltage tests. So far, we have been able to generate 2.4 kV pulses with approximately 340 ps response time (FWHM) using approximately a 200..mu..J optical pulse. Experiments are continuing to increase the voltage and improve the switching efficiency. 3 refs., 6 figs.

  15. Microwave pulse generation by photoconductive switching

    Science.gov (United States)

    Pocha, M. D.; Druce, R. L.

    1989-03-01

    Laser activated photoconductive semiconductor switching shows significant potential for application in high power microwave generation. Primary advantages of this concept are: small size, light weight, ruggedness, precise timing and phasing by optical control, and the potential for high peak power in short pulses. Several concepts have been suggested for microwave generation using this technology. They generally fall into two categories: (1) the frozen wave generator, or (2) tuned cavity modulation, both of which require only fast closing switches. We have been exploring a third possibility requiring fast closing and opening switches, that is the direct modulation of the switch at microwave frequencies. Switches have been fabricated at LLNL using neutron irradiated Gallium Arsenide which exhibit response times as short as 50 ps at low voltages. We are in the process of performing high voltage tests. So far, we have been able to generate 2.4 kV pulses with approximately 340 ps response time (FWHM) using approximately a 200 microJ optical pulse. Experiments are continuing to increase the voltage and improve the switching efficiency.

  16. PROGRAMMING THE MICROWAVE-OVEN

    NARCIS (Netherlands)

    KOK, LP; VISSER, PE; BOON, ME

    1994-01-01

    Microwaves can be used to stimulate chemical bonding, diffusion of reagents into and out of the specimen, and coagulation processes in preparatory techniques. Temperature plays an important role in these processes. There are several ways of controlling the temperature of microwave-exposed tissue,

  17. Microwave Radiometry in Remote Sensing

    DEFF Research Database (Denmark)

    Gudmandsen, Preben

    1982-01-01

    Microwave radiometry has shown its capabilities of observing and monitoring large-scale geophysical observables from space. Examples are sea surface temperature and surface wind over the ocean, sea ice extent, concentration and category and snow cover extent and water content. At low microwave fr...

  18. Advances on integrated microwave photonics

    DEFF Research Database (Denmark)

    Dong, Jianji; Liao, Shasha; Yan, Siqi

    2017-01-01

    Integrated microwave photonics has attracted a lot of attentions and makes significant improvement in last 10 years. We have proposed and demonstrated several schemes about microwave photonics including waveform generation, signal processing and energy-efficient micro-heaters. Our schemes are all...

  19. Computer-Generated Microwave Holograms.

    Science.gov (United States)

    Leming, Charles W.; Hastings, Orestes Patterson, III

    1980-01-01

    Described is the phasor method of superposition of waves. The intensity pattern from a system of microwave sources is calculated point by point on a plane corresponding to a film emulsion, and then printed and directly converted to a hologram for 3-cm microwaves. Calculations, construction, and viewing of holograms are included. (Author/DS)

  20. A reflexing electron microwave amplifier for rf particle accelerator applications

    International Nuclear Information System (INIS)

    Fazio, M.V.; Hoeberling, R.F.

    1988-01-01

    The evolution of rf-accelerator technology toward high-power, high-current, low-emittance beams produces an ever-increasing demand for efficient, very high power microwave power sources. The present klystron technology has performed very well but is not expected to produce reliable gigawatt peak-power units in the 1- to 10-GHz regime. Further major advancements must involve other types of sources. The reflexing-electron class of sources can produce microwave powers at the gigawatt level and has demonstrated operation from 800-MHz to 40-GHz. The pulse length appears to be limited by diode closure, and reflexing-electron devices have been operated in a repetitively pulsed mode. A design is presented for a reflexing electron microwave amplifier that is frequency and phase locked. In this design, the generated microwave power can be efficiently coupled to one or several accelerator loads. Frequency and phase-locking capability may permit parallel-source operation for higher power. The low-frequency (500-MHz to 10-GHz) operation at very high power required by present and proposed microwave particle accelerators makes an amplifier, based on reflexing electron phenomena, a candidate for the development of new accelerator power sources. (author)

  1. The cosmic microwave background

    International Nuclear Information System (INIS)

    Silk, J.

    1991-01-01

    Recent limits on spectral distortions and angular anisotropies in the cosmic microwave background are reviewed. The various backgrounds are described, and the theoretical implications are assessed. Constraints on inflationary cosmology dominated by cold dark matter (CDM) and on open cosmological models dominated by baryonic dark matter (BDM), with, respectively, primordial random phase scale-invariant curvature fluctuations or non-gaussian isocurvature fluctuations are described. More exotic theories are addressed, and I conclude with the 'bottom line': what theories expect experimentalists to be measuring within the next two to three years without having to abandon their most cherished theorists. (orig.)

  2. 2-mm microwave interferometer

    International Nuclear Information System (INIS)

    Futch, A.H.; Mortensen, W.K.

    1977-01-01

    A 2-mm microwave interferometer has been developed, and phase shift measurements have been made on the Baseball II experiment. The interferometer system employs a 140-GHz receiver for double down conversion of the plasma signal to a 60-MHz, IF frequency. The 140-GHz references signal is also down-converted and compared with the plasma signal to provide the desired phase change of the signal passing through the plasma. A feedback voltage from a 60-MHz discriminator to a voltage-controlled oscillator in the receiver provides frequency stability of the 60-MHz IF signals

  3. Microwave warning device

    International Nuclear Information System (INIS)

    Shriner, W.

    1981-01-01

    A device for warning a person carrying or wearing it of the presence of dangerous microwave radiation is fully powered by the radiations being detected. A very low-wattage gas-discharge lamp is energized by a broadly or a sharply tuned receiver circuit including dipole antennas or one antenna and a ''grounding'' casing element. The casing may be largely and uniformly transparent or have different areas gradedly light-transmissive to indicate varying radiation intensities. The casing can be made in the shape of a pocket watch, fountain pen, bracelet or finger ring, etc

  4. Resonant freak microwaves

    International Nuclear Information System (INIS)

    Aguiar, F.M. de

    2011-01-01

    The Helmholtz equation describing transverse magnetic modes in a closed flat microwave resonator with 60 randomly distributed discs is numerically solved. At lower frequencies, the calculated wave intensity spatially distributed obeys the universal Porter-Thomas form if localized modes are excluded. A superposition of resonant modes is shown to lead to rare events of extreme intensities (freak waves) at localized 'hot spots'. The temporally distributed intensity of such a superposition at the center of a hot spot also follows the Porter-Thomas form. Branched modes are found at higher frequencies. The results bear resemblance to recent experiments reported in an open cavity.

  5. DSN Microwave Antenna Holography

    Science.gov (United States)

    Rochblatt, D. J.; Seidel, B. L.

    1984-01-01

    The DSN microwave antenna holography project will obtain three-dimensional pictures of the large DSN antenna surfaces. These pictures must be of suffi icient resolution to allow adjustment of the reflector panels to an rms surface of 0.5 mm (0.25 mm, goal). The major parameters and equations needed to define a holographic measurement system are outlined and then the proof of concept demonstration measurement that was made at DSS-43 (Australia) that resulted in contour maps with spatial resolution of 7 m in the aperture plane and resolution orthogonal to the aperture plane of 0.7 mm was discussed.

  6. Evaluating superconductors for microwave applications

    International Nuclear Information System (INIS)

    Hammond, B.; Bybokas, J.

    1989-01-01

    It is becoming increasingly obvious that some of the earliest applications for high Tc superconductors will be in the microwave market. While this is a major opportunity for the superconductor community, it also represents a significant challenge. At DC or low frequencies a superconductor can be easily characterized by simple measurements of resistivity and magnetic susceptibility versus temperature. These parameters are fundamental to superconductor characterization and various methods exist for measuring them. The only valid way to determine the microwave characteristics of a superconductor is to measure it at microwave frequencies. It is for this reason that measuring microwave surface resistance has emerged as one of the most demanding and telling tests for materials intended for high frequency applications. In this article, the theory of microwave surface resistance is discussed. Methods for characterizing surface resistance theoretically and by practical implementation are described

  7. A multifunctional microwave plasma reaction apparatus and its applications

    International Nuclear Information System (INIS)

    Wang Xizhang; Wu Qiang; Hu Zheng; Xu Hua; Miao Shui; Chen Yi

    2000-01-01

    A multifunctional apparatus for microwave plasma reaction has been set up, which can be used in the fields such as chemical synthesis, surface modification, and heterogeneous catalysis. The apparatus has laid an experimental foundation for new methods, new technologies, and new train of thoughts to be explored

  8. Microwave-Assisted Hydantoins Synthesis on Solid Support

    Science.gov (United States)

    Coursindel, Thibault; Martinez, Jean; Parrot, Isabelle

    2010-01-01

    In this laboratory activity, students are introduced to a three-step synthesis of hydantoin (imidazolidine-2,4-dione), a moiety that is found in many biologically active compounds. Using a microwave oven and solid-support technology, this synthetic experiment is designed for masters-degree candidates working in organic chemistry or upper-level…

  9. Microwave systems design

    CERN Document Server

    Awang, Zaiki

    2014-01-01

    The aim of this book is to serve as a design reference for students and as an up-to-date reference for researchers. It also acts as an excellent introduction for newcomers to the field and offers established rf/microwave engineers a comprehensive refresher.  The content is roughly classified into two – the first two chapters provide the necessary fundamentals, while the last three chapters focus on design and applications. Chapter 2 covers detailed treatment of transmission lines. The Smith chart is utilized in this chapter as an important tool in the synthesis of matching networks for microwave amplifiers. Chapter 3 contains an exhaustive review of microstrip circuits, culled from various references. Chapter 4 offers practical design information on solid state amplifiers, while Chapter 5 contains topics on the design of modern planar filters, some of which were seldom published previously. A set of problems at the end of each chapter provides the readers with exercises which were compiled from actual uni...

  10. Microwave mediated synthesis of spiro-(indoline-isoxazolidines): mechanistic study and biological activity evaluation

    DEFF Research Database (Denmark)

    Raunak, R.; Kumar, Vineet; Mukherjee, Shubhasish

    2005-01-01

    Regioisomeric spiro-(indoline-isoxazolidines) have been synthesized in moderate yields by the cycloaddition reaction between ethyl (3-indolylidene)acetate and various substituted α,N-diphenylnitrones, using environmentally benign microwave technology. A novel concerted reaction mechanism is descr......Regioisomeric spiro-(indoline-isoxazolidines) have been synthesized in moderate yields by the cycloaddition reaction between ethyl (3-indolylidene)acetate and various substituted α,N-diphenylnitrones, using environmentally benign microwave technology. A novel concerted reaction mechanism...

  11. Advances on simultaneous desulfurization and denitrification using activated carbon irradiated by microwaves.

    Science.gov (United States)

    Ma, Shuang-Chen; Gao, Li; Ma, Jing-Xiang; Jin, Xin; Yao, Juan-Juan; Zhao, Yi

    2012-06-01

    This paper describes the research background and chemistry of desulfurization and denitrification technology using microwave irradiation. Microwave-induced catalysis combined with activated carbon adsorption and reduction can reduce nitric oxide to nitrogen and sulfur dioxide to sulfur from flue gas effectively. This paper also highlights the main drawbacks of this technology and discusses future development trends. It is reported that the removal of sulfur dioxide and nitric oxide using microwave irradiation has broad prospects for development in the field of air pollution control.

  12. Microwave Frequency Multiplier

    Science.gov (United States)

    Velazco, J. E.

    2017-02-01

    High-power microwave radiation is used in the Deep Space Network (DSN) and Goldstone Solar System Radar (GSSR) for uplink communications with spacecraft and for monitoring asteroids and space debris, respectively. Intense X-band (7.1 to 8.6 GHz) microwave signals are produced for these applications via klystron and traveling-wave microwave vacuum tubes. In order to achieve higher data rate communications with spacecraft, the DSN is planning to gradually furnish several of its deep space stations with uplink systems that employ Ka-band (34-GHz) radiation. Also, the next generation of planetary radar, such as Ka-Band Objects Observation and Monitoring (KaBOOM), is considering frequencies in the Ka-band range (34 to 36 GHz) in order to achieve higher target resolution. Current commercial Ka-band sources are limited to power levels that range from hundreds of watts up to a kilowatt and, at the high-power end, tend to suffer from poor reliability. In either case, there is a clear need for stable Ka-band sources that can produce kilowatts of power with high reliability. In this article, we present a new concept for high-power, high-frequency generation (including Ka-band) that we refer to as the microwave frequency multiplier (MFM). The MFM is a two-cavity vacuum tube concept where low-frequency (2 to 8 GHz) power is fed into the input cavity to modulate and accelerate an electron beam. In the second cavity, the modulated electron beam excites and amplifies high-power microwaves at a frequency that is a multiple integer of the input cavity's frequency. Frequency multiplication factors in the 4 to 10 range are being considered for the current application, although higher multiplication factors are feasible. This novel beam-wave interaction allows the MFM to produce high-power, high-frequency radiation with high efficiency. A key feature of the MFM is that it uses significantly larger cavities than its klystron counterparts, thus greatly reducing power density and arcing

  13. Utilization of microwave energy for decontamination of oil polluted soils.

    Science.gov (United States)

    Iordache, Daniela; Niculae, Dumitru; Francisc, Ioan Hathazi

    2010-01-01

    Soil oil (petroleum) product pollution represents a great environmental threat as it may contaminate the neighboring soils and surface and underground water. Liquid fuel contamination may occur anywhere during oil (petroleum) product transportation, storing, handling and utilization. The polluted soil recovery represents a complex process due to the wide range of physical, chemical and biological properties of soils which should be analyzed in connection with the study of the contaminated soil behavior under the microwave field action. The soil, like any other non-metallic material, can be heated through microwave energy absorption due to the dielectric losses, expressed by its dielectric complex constant. Oil polluted soil behaves differently in a microwave field depending on the nature, structure and amount of the polluting fuel. Decontamination is performed through volatilization and retrieval of organic contaminant volatile components. After decontamination only a soil fixed residue remains, which cannot penetrate the underground anymore. In carrying out the soil recovery process by means of this technology we should also consider the soil characteristics such as: the soil type, temperature, moisture.The first part of the paper presents the theoretical aspects relating to the behavior of the polluted soil samples in the microwave field, as well as their relating experimental data. The experimental data resulting from the analysis of soils with a different level of pollution point out that the degree of pollutant recovery is high, contributing to changing the initial classification of soils from the point of view of pollution. The paper graphically presents the levels of microwave generated and absorbed power in soil samples, soil temperature during experimentations, specific processing parameters in a microwave field. It also presents the constructive solution of the microwave equipment designed for the contaminated soil in situ treatment.

  14. Synthesis of cocarboxylase: process intensification via microwave irradiation

    OpenAIRE

    Пинчукова, Наталия Александровна; Волошко, Александр Юрьевич; Горобец, Николай Юрьевич; Беликов, Константин Николаевич; Гудзенко, Людмила Васильевна; Чебанов, Валентин Анатольевич

    2013-01-01

    Energy saving is the key point in the development of new chemical technologies and industrial scaling of the processes of obtaining chemical reagents, functional materials, pharmaceutical substances, etc. The use of the non-classical process activation methods, including microwave radiation, known as effective heating source, allowing significant process acceleration, is a promising direction in the field of new energy-saving technologies.The paper gives the results of modeling of the process...

  15. Microwave and pulsed power engineering

    International Nuclear Information System (INIS)

    Hofer, W.W.

    1984-01-01

    The Microwave and Pulsed Power Engineering Thrust Area is responsible for developing the short-term and long-term engineering resources required to support the growing microwave and pulsed power engineering requirements of several LLNL Programs. The responsibility of this Thrust Area is to initiate applicable research and development projects and to provide capabilities and facilities to permit engineers involved in these and other programs to make significant contributions. In this section, the principal projects are described: dielectric failure prediction using partial discharge analysis, coating dielectrics to increase surface flashover potential, and the microwave generator experiment

  16. Microwave Absorption Characteristics of Tire

    Science.gov (United States)

    Zhang, Yuzhe; Hwang, Jiann-Yang; Peng, Zhiwei; Andriese, Matthew; Li, Bowen; Huang, Xiaodi; Wang, Xinli

    The recycling of waste tires has been a big environmental problem. About 280 million waste tires are produced annually in the United States and more than 2 billion tires are stockpiled, which cause fire hazards and health issues. Tire rubbers are insoluble elastic high polymer materials. They are not biodegradable and may take hundreds of years to decompose in the natural environment. Microwave irradiation can be a thermal processing method for the decomposition of tire rubbers. In this study, the microwave absorption properties of waste tire at various temperatures are characterized to determine the conditions favorable for the microwave heating of waste tires.

  17. Microwave antenna holography

    Science.gov (United States)

    Rochblatt, David J.; Seidel, Boris L.

    1992-01-01

    This microwave holography technique utilizes the Fourier transform relation between the complex far field radiation pattern of an antenna and the complex aperture field distribution. Resulting aperture phase and amplitude distribution data can be used to precisely characterize various crucial performance parameters, including panel alignment, panel shaping, subreflector position, antenna aperture illumination, directivity at various frequencies, and gravity deformation effects. The methodology of data processing presented here was successfully applied to the Deep Space Network (DSN) 34-m beam waveguide antennas. The antenna performance was improved at all operating frequencies by reducing the main reflector mechanical surface rms error to 0.43 mm. At Ka-band (32 GHz), the estimated improvement is 4.1 dB, resulting in an aperture efficiency of 52 percent. The performance improvement was verified by efficiency measurements and additional holographic measurements.

  18. Direct Synthesis of Microwave Waveforms for Quantum Computing

    Science.gov (United States)

    Raftery, James; Vrajitoarea, Andrei; Zhang, Gengyan; Leng, Zhaoqi; Srinivasan, Srikanth; Houck, Andrew

    Current state of the art quantum computing experiments in the microwave regime use control pulses generated by modulating microwave tones with baseband signals generated by an arbitrary waveform generator (AWG). Recent advances in digital analog conversion technology have made it possible to directly synthesize arbitrary microwave pulses with sampling rates of 65 gigasamples per second (GSa/s) or higher. These new ultra-wide bandwidth AWG's could dramatically simplify the classical control chain for quantum computing experiments, presenting potential cost savings and reducing the number of components that need to be carefully calibrated. Here we use a Keysight M8195A AWG to study the viability of such a simplified scheme, demonstrating randomized benchmarking of a superconducting qubit with high fidelity.

  19. Measurement of spin pumping voltage separated from extrinsic microwave effects

    International Nuclear Information System (INIS)

    Iguchi, Ryo; Saitoh, Eiji

    2017-01-01

    Conversions between spin and charge currents are core technologies in recent spintronics. In this article, we provide methods for estimating inverse spin Hall effects (ISHEs) induced by using microwave-driven spin pumping (SP) as a spin-current generator. ISHE and SP induce an electromotive force at the ferromagnetic or spin-wave resonance, which offers a valuable electric method of studying spin physics in materials. At the resonance, a microwave for exciting the magnetization dynamics induces an additional electromotive force via rf-current rectification and thermoelectric effects. We discuss methods of separating the signals generated from such extrinsic microwave effects by controlling sample structures and configurations. These methods are helpful in performing accurate measurements on ISHE induced by SP, enabling quantitative studies on the conversion between spin and charge currents on various kinds of materials. (author)

  20. An introduction to microwave imaging for breast cancer detection

    CERN Document Server

    Conceição, Raquel Cruz; O'Halloran, Martin

    2016-01-01

    This book collates past and current research on one of the most promising emerging modalities for breast cancer detection. Readers will discover how, as a standalone technology or in conjunction with another modality, microwave imaging has the potential to provide reliable, safe and comfortable breast exams at low cost. Current breast imaging modalities include X- ray, Ultrasound, Magnetic Resonance Imaging, and Positron Emission Tomography. Each of these methods suffers from limitations, including poor sensitivity or specificity, high cost, patient discomfort, and exposure to potentially harmful ionising radiation. Microwave breast imaging is based on a contrast in the dielectric properties of breast tissue that exists at microwave frequencies. The book begins by considering the anatomy and dielectric properties of the breast, contrasting historical and recent studies. Next, radar-based breast imaging algorithms are discussed, encompassing both early-stage artefact removal, and data independent and adaptive ...

  1. Technology.

    Science.gov (United States)

    Online-Offline, 1998

    1998-01-01

    Focuses on technology, on advances in such areas as aeronautics, electronics, physics, the space sciences, as well as computers and the attendant progress in medicine, robotics, and artificial intelligence. Describes educational resources for elementary and middle school students, including Web sites, CD-ROMs and software, videotapes, books,…

  2. Microwave energy transmission test toward the SPS using the space station

    Energy Technology Data Exchange (ETDEWEB)

    Kaya, N.; Matsumoto, H.; Miyatake, S.; Kimura, I.; Nagatomo, M.

    1986-12-01

    An outline of a project METT (Microwave Energy Transmission Test) using the Space Station is described. The objectives of the METT are to develop and test the technology of microwave energy transmission for the future Solar Power Satellite (SPS), and to estimate the environmental effects of the high power microwaves on the ionosphere and the atmosphere. Energy generated with solar cells is transmitted from a transmitting antenna on the bus platform near the Space Station to a rectenna on the sub-satellite or the ground station in order to test the total efficiency and the functions of the developed system of the energy transmission. Plasma similar to that in the D and E layers in the ionosphere is produced in a large balloon opened on the sub-satellite in order to investigate possible interactions between the SPS microwave and the ionospheric plasma and to determine the maximum power density of the microwave beam which passes through the ionosphere.

  3. Tracking Code for Microwave Instability

    International Nuclear Information System (INIS)

    Heifets, S.; SLAC

    2006-01-01

    To study microwave instability the tracking code is developed. For bench marking, results are compared with Oide-Yokoya results [1] for broad-band Q = 1 impedance. Results hint to two possible mechanisms determining the threshold of instability

  4. Tapping mode microwave impedance microscopy

    KAUST Repository

    Lai, K.; Kundhikanjana, W.; Peng, H.; Cui, Y.; Kelly, M. A.; Shen, Z. X.

    2009-01-01

    We report tapping mode microwave impedance imaging based on atomic force microscope platforms. The shielded cantilever probe is critical to localize the tip-sample interaction near the tip apex. The modulated tip-sample impedance can be accurately

  5. Hurricane Satellite (HURSAT) Microwave (MW)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Hurricane Satellite (HURSAT) from Microwave (MW) observations of tropical cyclones worldwide data consist of raw satellite observations. The data derive from the...

  6. Microwave-assisted flow processing in heterogeneously copper nano-catalyzed reactions

    NARCIS (Netherlands)

    Benaskar, F.

    2012-01-01

    In the last decades, micro-processing and microwave technology have been established as mature technologies, however, mainly instigated by academia. Many advances in micro-process technology have led to novel routes and/or process windows to replace batch operations by more efficient continuous

  7. Cosmic microwave background, where next?

    CERN Multimedia

    CERN. Geneva

    2009-01-01

    Ground-based, balloon-borne and space-based experiments will observe the Cosmic Microwave Background in greater details to address open questions about the origin and the evolution of the Universe. In particular, detailed observations the polarization pattern of the Cosmic Microwave Background radiation have the potential to directly probe physics at the GUT scale and illuminate aspects of the physics of the very early Universe.

  8. Magnon transport through microwave pumping

    OpenAIRE

    Nakata Kouki; Simon Pascal; Loss Daniel

    2015-01-01

    We present a microscopic theory of magnon transport in ferromagnetic insulators (FIs). Using magnon injection through microwave pumping, we propose a way to generate magnon dc currents and show how to enhance their amplitudes in hybrid ferromagnetic insulating junctions. To this end focusing on a single FI, we first revisit microwave pumping at finite (room) temperature from the microscopic viewpoint of magnon injection. Next, we apply it to two kinds of hybrid ferromagnetic insulating juncti...

  9. Microwaves absorption in superconducting materials

    International Nuclear Information System (INIS)

    Biasi, R.S. de; Fernandes, A.A.R.; Pereira, R.F.R.

    1989-01-01

    Microwaves absorption measures in two superconductors ceramics systems, Y-Ba-Cu-O and Bi-Sr-Ca-Cu-O are compared with similars datas obtained in the same band of temperature by a conventional method, mutual inductance. The results suggest that the microwaves absorption can be used as single and non-destructive method for investigating the properties of ceramics superconductors. (C.G.C.) [pt

  10. Microwave effects in Drosophila melanogaster

    International Nuclear Information System (INIS)

    Dardalhon, M.; Averbeck, D.; Berteaud, A.J.

    1979-01-01

    Experiments were set up to investigate the effects of open space microwave irradiation of the millimeter (73 GHz) and the centimeter (17 GHz) range in Drosophila melanogaster. We used the wild type strain Paris and the strain delta carrying melanitic tumors in the 3rd larval stage, in the pupae and the adults. The power densities were up to 100mW.cm -2 for 73 GHz and about 60 mW.cm -2 for microwaves at 17 GHz. After 2h exposure to microwaves of 17 GHz or 73 GHz the hatching of the irradiated eggs and their development were normal. In a few cases there was a tendency towards a diminution of the survival of eggs treated at different stages, of larvae treated in the stages 1, 2 and 3 and of treated pupae. However, this was not always statistically significant. The microwave treatment did not induce teratological changes in the adults. A statistical analysis brought about slight diminutions in the incidence and multiplicity of tumors in adult flies. When wild type females were exposed to microwaves of 17 GHz for 16 or 21 h and crossed with untreated males we observed a marked increase in fertility as compared to untreated samples. The viability and tumor incidence in the offspring was not affected. Similar results were obtained when microwaves treated males were crossed with untreated females

  11. Study of federal microwave standards

    Energy Technology Data Exchange (ETDEWEB)

    David, L.

    1980-08-01

    Present and future federal regulatory processes which may impact the permissible levels of microwave radiation emitted by the SPS Microwave Power Transmission (MPTS) were studied. An historical development of US occupational and public microwave standards includes an overview of Western and East European philosophies of environmental protection and neurophysiology which have led to the current widely differing maximum permissible exposure limits to microwaves. The possible convergence of microwave standards is characterized by a lowering of Western exposure levels while Eastern countries consider standard relaxation. A trend toward stricter controls on activities perceived as harmful to public health is under way as is interest in improving the federal regulatory process. Particularly relevant to SPS is the initiation of long-term, low-level microwave exposure programs. Coupled with new developments in instrumentation and dosimetry, the results from chronic exposure program and population exposure studies could be expected within the next five to ten years. Also discussed is the increasing public concern that rf energy is yet another hazardous environmental agent.

  12. History and status of beamed power technology and applications at 2.45 Gigahertz

    Science.gov (United States)

    Brown, William C.

    1989-01-01

    Various applications of beamed power technology are discussed. An experimental microwave powered helicopter, rectenna technology, the use of the Solar Power Satellite to beam energy to Earth via microwaves, the use of cyclotron resonance devices, microwave powered airships, and electric propulsion are discussed.

  13. Microwave heating processes involving carbon materials

    Energy Technology Data Exchange (ETDEWEB)

    Menendez, J.A.; Arenillas, A.; Fidalgo, B.; Fernandez, Y.; Zubizarreta, L.; Calvo, E.G.; Bermudez, J.M. [Instituto Nacional del Carbon, CSIC, Apartado 73, 33080 Oviedo (Spain)

    2010-01-15

    Carbon materials are, in general, very good absorbents of microwaves, i.e., they are easily heated by microwave radiation. This characteristic allows them to be transformed by microwave heating, giving rise to new carbons with tailored properties, to be used as microwave receptors, in order to heat other materials indirectly, or to act as a catalyst and microwave receptor in different heterogeneous reactions. In recent years, the number of processes that combine the use of carbons and microwave heating instead of other methods based on conventional heating has increased. In this paper some of the microwave-assisted processes in which carbon materials are produced, transformed or used in thermal treatments (generally, as microwave absorbers and catalysts) are reviewed and the main achievements of this technique are compared with those obtained by means of conventional (non microwave-assisted) methods in similar conditions. (author)

  14. Controlled Microwave Heating Accelerates Rolling Circle Amplification.

    Science.gov (United States)

    Yoshimura, Takeo; Suzuki, Takamasa; Mineki, Shigeru; Ohuchi, Shokichi

    2015-01-01

    Rolling circle amplification (RCA) generates single-stranded DNAs or RNA, and the diverse applications of this isothermal technique range from the sensitive detection of nucleic acids to analysis of single nucleotide polymorphisms. Microwave chemistry is widely applied to increase reaction rate as well as product yield and purity. The objectives of the present research were to apply microwave heating to RCA and indicate factors that contribute to the microwave selective heating effect. The microwave reaction temperature was strictly controlled using a microwave applicator optimized for enzymatic-scale reactions. Here, we showed that microwave-assisted RCA reactions catalyzed by either of the four thermostable DNA polymerases were accelerated over 4-folds compared with conventional RCA. Furthermore, the temperatures of the individual buffer components were specifically influenced by microwave heating. We concluded that microwave heating accelerated isothermal RCA of DNA because of the differential heating mechanisms of microwaves on the temperatures of reaction components, although the overall reaction temperatures were the same.

  15. Microwave catalytic NOx and SO{sub 2} removal using FeCu/zeolite as catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Z.S. Wei; G.H. Zeng; Z.R. Xie; C.Y. Ma; X.H. Liu; J.L. Sun; L.H. Liu [Sun Yat-sen University, Guangzhou (China). School of Environmental Science and Engineering

    2011-04-15

    Non-thermal plasma technology is a promising process for flue gas treatment. Microwave catalytic NOx and SO{sub 2} removal simultaneously has been investigated using FeCu/zeolite as catalyst. The experimental results showed that a microwave reactor with FeCu/zeolite only could be used to microwave catalytic oxidative 91.7% NOx to nitrates and 79.6% SO{sub 2} to sulfate; the reaction efficiencies of microwave catalytic reduction of NOx and SO{sub 2} in a microwave reactor with FeCu/zeolite and ammonium bicarbonate (NH{sub 4}HCO{sub 3}) as a reducing agent could be up to 95.8% and 93.4% respectively. Microwave irradiation accentuates catalytic reduction of SO{sub 2} and NOx treatment, and microwave addition can increases SO{sub 2} removal efficiency from 14.5% to 18.7%, and NOx removal efficiency from 13.4% to 18.7%, separately. FeCu/zeolite catalyst was characterized by X-ray diffraction (XRD), X-ray photoelectron spectrum analysis (XPS), scanning electron microscopy (SEM) and the Brunauer Emmett Teller (BET) method. Microwave catalytic NOx and SO{sub 2} removal follows Langmuir-Hinshelwood (L-H) kinetics. 25 refs., 7 figs., 1 tab.

  16. Experimental and numerical modeling research of rubber material during microwave heating process

    Science.gov (United States)

    Chen, Hailong; Li, Tao; Li, Kunling; Li, Qingling

    2018-05-01

    This paper aims to investigate the heating behaviors of block rubber by experimental and simulated method. The COMSOL Multiphysics 5.0 software was utilized in numerical simulation work. The effects of microwave frequency, power and sample size on temperature distribution are examined. The effect of frequency on temperature distribution is obvious. The maximum and minimum temperatures of block rubber increase first and then decrease with frequency increasing. The microwave heating efficiency is maximum in the microwave frequency of 2450 MHz. However, more uniform temperature distribution is presented in other microwave frequencies. The influence of microwave power on temperature distribution is also remarkable. The smaller the power, the more uniform the temperature distribution on the block rubber. The effect of power on microwave heating efficiency is not obvious. The effect of sample size on temperature distribution is evidently found. The smaller the sample size, the more uniform the temperature distribution on the block rubber. However, the smaller the sample size, the lower the microwave heating efficiency. The results can serve as references for the research on heating rubber material by microwave technology.

  17. WiMAX technology and network evolution

    CERN Document Server

    Etemad, Kamran

    2010-01-01

    WiMAX, the Worldwide Interoperability for Microwave Access, represents a paradigm shift in telecommunications technology. It offers the promise of cheaper, smaller, and simpler technology compared to existing broadband options such as DSL, cable, fiber, and 3G wireless.

  18. Suitability of microwave drying for mealworms (Tenebrio molitor) as alternative to freeze drying: Impact on nutritional quality and colour.

    Science.gov (United States)

    Lenaerts, S; Van Der Borght, M; Callens, A; Van Campenhout, L

    2018-07-15

    Freeze drying represents the current practice to stabilize mealworms, even though it is an energy demanding technique. Therefore, it was examined in the present study whether microwave drying could be a proper alternative. To this end, the impact of both drying techniques on the proximate composition, vitamin B 12 content, fatty acid profile, oxidation status and colour parameters of mealworms was investigated. Furthermore, the influence of the application of vacuum during microwave drying was studied. The different drying technologies resulted in small differences in the proximate composition, while the vitamin B 12 content was only reduced by microwave drying. The fat fraction of freeze dried mealworms showed a higher oxidation status than the fat of microwave dried mealworms. Application of a vacuum during the microwave drying process did not appear to offer advantages. This research shows that for mealworms microwave drying can be a proper alternative to freeze drying. Copyright © 2018 Elsevier Ltd. All rights reserved.

  19. Technology

    Directory of Open Access Journals (Sweden)

    Xu Jing

    2016-01-01

    Full Text Available The traditional answer card reading method using OMR (Optical Mark Reader, most commonly, OMR special card special use, less versatile, high cost, aiming at the existing problems proposed a method based on pattern recognition of the answer card identification method. Using the method based on Line Segment Detector to detect the tilt of the image, the existence of tilt image rotation correction, and eventually achieve positioning and detection of answers to the answer sheet .Pattern recognition technology for automatic reading, high accuracy, detect faster

  20. Anisotropic Dielectric Properties of Carbon Fiber Reinforced Polymer Composites during Microwave Curing

    Science.gov (United States)

    Zhang, Linglin; Li, Yingguang; Zhou, Jing

    2018-01-01

    Microwave cuing technology is a promising alternative to conventional autoclave curing technology in high efficient and energy saving processing of polymer composites. Dielectric properties of composites are key parameters related to the energy conversion efficiency during the microwave curing process. However, existing methods of dielectric measurement cannot be applied to the microwave curing process. This paper presented an offline test method to solve this problem. Firstly, a kinetics model of the polymer composites under microwave curing was established based on differential scanning calorimetry to describe the whole curing process. Then several specially designed samples of different feature cure degrees were prepared and used to reflect the dielectric properties of the composite during microwave curing. It was demonstrated to be a feasible plan for both test accuracy and efficiency through extensive experimental research. Based on this method, the anisotropic complex permittivity of a carbon fiber/epoxy composite during microwave curing was accurately determined. Statistical results indicated that both the dielectric constant and dielectric loss of the composite increased at the initial curing stage, peaked at the maximum reaction rate point and decreased finally during the microwave curing process. Corresponding mechanism has also been systematically investigated in this work.

  1. GA microwave window development

    International Nuclear Information System (INIS)

    Moeller, C.P.; Kasugai, A.; Sakamoto, K.; Takahashi, K.

    1994-10-01

    The GA prototype distributed window was tested in a 32 mm diam. waveguide system at a power density suitable for a MW gyrotron, using the JAERI/Toshiba 110 GHz long pulse internal converter gyrotron in the JAERI test stand. The presence of the untilted distributed window had no adverse effect on the gyrotron operation. A pulse length of 10 times the calculated thermal equilibrium time (1/e time) of 30 msec was reached, and the window passed at least 750 pulses greater than 30 msec and 343 pulses greater than 60 msec. Beyond 100 msec, the window calorimetry reached steady state, allowing the window dissipation to be measured in a single pulse. The measured loss of 4.0% agrees both with the estimated loss, on which the stress calculations are based, and with the attenuation measured at low power in the HE 11 mode. After the end of the tests, the window was examined; no evidence of arcing air coating was found in the part of the window directly illuminated by the microwaves, although there was discoloration in a recess containing an optical diagnostic which outgassed, causing a local discharge to occur in that recess. Finally, there was no failure of the metal-sapphire joints during a total operating time of 50 seconds consisting of pulses longer than 30 msec

  2. Microwave solar limb brightening

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, I A; Kundu, M R [Maryland Univ., College Park (USA)

    1981-02-01

    Previous models of microwave limb brightening have omitted the alignment of spicules along supergranule boundaries, have neglected the high temperature sheath around spicules, and have assumed an interspicular medium which was averaged over chromospheric network and non-network regions. We present a model which includes these factors. By constraining the model to conform to results from earlier UV and optical studies we are effectively left with two free parameters: the temperature at the core of the spicules, Tsub(c)sub(o)sub(r)sub(e), and (at solar minimum), the interspicular chromospheric network density model of the lower transition zone. The absence of limb brightening at the short millimeter wavelengths implies Tsub(c)sub(o)sub(r)sub(e) approx. < 6000 k. Differences between the model and certain deconvolved observations near 9 mm are expected as a consequence of an extension of emission beyond the optical limb, predicted by the model, which affects the accuracy of the deconvolution technique. Unlike models which assume homogeous spicules in a random distribution, ours does not require an abnormally high spicule area.

  3. Linear, Low Noise Microwave Photonic Systems using Phase and Frequency Modulation

    Science.gov (United States)

    2012-05-11

    Lightwave Technology, Journal of, vol. 24, no. 12, pp. 4628 –4641, Dec 2006. [2] J. Capmany and D. Novak, “Microwave photonics combines two worlds...Journal of, vol. 32, no. 7, pp. 1141 –1149, Jul 1996. [13] J. Capmany and D. Novak, “Microwave photonics combines two worlds,” Nature Photonics, vol. 1, no... Capmany , “Analytical model and figures of merit for filtered Microwave photonic links,” Opt. Express, vol. 19, no. 20, pp. 19 758–19 774, Sep 2011

  4. Wideband 360 degrees microwave photonic phase shifter based on slow light in semiconductor optical amplifiers.

    Science.gov (United States)

    Xue, Weiqi; Sales, Salvador; Capmany, José; Mørk, Jesper

    2010-03-15

    In this work we demonstrate for the first time, to the best of our knowledge, a continuously tunable 360 degrees microwave phase shifter spanning a microwave bandwidth of several tens of GHz (up to 40 GHz). The proposed device exploits the phenomenon of coherent population oscillations, enhanced by optical filtering, in combination with a regeneration stage realized by four-wave mixing effects. This combination provides scalability: three hybrid stages are demonstrated but the technology allows an all-integrated device. The microwave operation frequency limitations of the suggested technique, dictated by the underlying physics, are also analyzed.

  5. On-line measurement of microwave power in ECR ion source

    International Nuclear Information System (INIS)

    Zhou Changgeng; Kang Wu; Hu Yonghong; Li Yan; Lou Benchao; Zu Xiulan; Xiong Riheng; Chen Junguang; Li Xiaoyun

    2005-01-01

    It is a new technology to apply an ECR ion source to the neutron generator. Because of the structure limitation, working state of the ECR ion source could not be judged by the color of gas discharging in discharge chamber. Therefore, it was hard to estimate if the ECR ion source was working properly in the neutron generator. The method to resolve the problem was described in this paper. The microwave power was measured on-line by a directional coupler and a small microwave power meter. The ion beam current could be educed from the measured incidence microwave power, and discharge state in discharge chamber could be determined. (authors)

  6. Application of microwave energy in the control of DPM, oxides of nitrogen and VOC emissions

    Science.gov (United States)

    Pallavkar, Sameer M.

    The emissions of DPM (diesel particulate matter), NOx (oxides of nitrogen), and toxic VOCs (volatile organic compounds) from diesel engine exhaust gases and other sources such as chemical process industry and manufacturing industry have been a great environmental and health concern. Most control technologies for these emissions require elevated temperatures. The use of microwave energy as a source of heat energy, however, has not been fully explored. In this study, the microwave energy was used as the energy source in three separate emission control processes, namely, the regeneration of diesel particulate filter (DPF) for DPM control, the NOx reduction using a platinum catalyst, and the VOC destruction involving a ceramic based material. The study has demonstrated that microwave heating is an effective method in providing heat for the studied processes. The control efficiencies associated with the microwave-assisted processes have been observed to be high and acceptable. Further research, however, is required for the commercial use of these technologies.

  7. Microwave demolition tool for mounting on a long range manipulator (EMIR)

    International Nuclear Information System (INIS)

    Wace, P.F.; Hamblin, C.; Shute, R.A.

    1993-01-01

    As part of the CEC's supported programme on the Development of Decommissioning Technologies, AEA Technology agreed to collaborate with KfK Karlsruhe who were developing the EMIR, a remote handling device, and testing it to deploy tools suitable for use in decommissioning applications. The AEA undertook to develop and supply a microwave tool for evaluation. The programme aims were: to produce a microwave tool that could be deployed by EMIR; to evaluate the manoeuvrability of such a device; to determine the manoeuvrability of EMIR when deploying the microwave tool; to measure the microwave leakage. The tool was successfully developed to time and budget and has been interfaced with EMIR at Karlsruhe. A short series of tests has been carried out, positioning the tool against a concrete test piece. Satisfactory results were obtained and these have established the practical working and design parameters for tools of this type and have shown that EMIR is capable of deploying a tool weighing 660 kg. (author)

  8. Microwave, Millimeter, Submillimeter, and Far Infrared Spectral Databases

    Science.gov (United States)

    Pearson, J. C.; Pickett, H. M.; Drouin, B. J.; Chen, P.; Cohen, E. A.

    2002-01-01

    The spectrum of most known astrophysical molecules is derived from transitions between a few hundred to a few hundred thousand energy levels populated at room temperature. In the microwave and millimeter wave regions. spectroscopy is almost always performed with traditional microwave techniques. In the submillimeter and far infrared microwave technique becomes progressively more technologically challenging and infrared techniques become more widely employed as the wavelength gets shorter. Infrared techniques are typically one to two orders of magnitude less precise but they do generate all the strong features in the spectrum. With microwave technique, it is generally impossible and rarely necessary to measure every single transition of a molecular species, so careful fitting of quantum mechanical Hamiltonians to the transitions measured are required to produce the complete spectral picture of the molecule required by astronomers. The fitting process produces the most precise data possible and is required in the interpret heterodyne observations. The drawback of traditional microwave technique is that precise knowledge of the band origins of low lying excited states is rarely gained. The fitting of data interpolates well for the range of quantum numbers where there is laboratory data, but extrapolation is almost never precise. The majority of high resolution spectroscopic data is millimeter or longer in wavelength and a very limited number of molecules have ever been studied with microwave techniques at wavelengths shorter than 0.3 millimeters. The situation with infrared technique is similarly dire in the submillimeter and far infrared because the black body sources used are competing with a very significant thermal background making the signal to noise poor. Regardless of the technique used the data must be archived in a way useful for the interpretation of observations.

  9. PET based nanocomposite films for microwave packaging applications

    International Nuclear Information System (INIS)

    Galdi, M. R.; Olivieri, R.; Liguori, L.; Albanese, D.; Di Matteo, M.; Di Maio, L.

    2015-01-01

    In recent years, changes in life standards have promoted the diffusion of Ready to Cook (RTC) and Ready to Eat (RTE) products for microwave ovens. However, the main limits in microwave (MW) ovens usage are often related to the proper choice of packaging materials suitable for such technology. In fact, packages for microwaveable RTC and RTE foods should ensure adequate preservation of the product before cooking/heating such as high barriers to gases and aromas and adequate control of water vapor transmission. In addition, microwaveable packaging material must be transparent to MW, thermally stable and resistant to the mechanical stress induced by the accumulation in the head space of volatile substances produced during the cooking. Polymeric materials are good candidates for microwaveable packaging thanks to their transparency to MW. In the last years a great interest is devoted to developing innovative solution based on the use of additives or systems that act as susceptors or heating enhancers for improving the characteristics of polymers in cooking/heating in MW ovens. The present work was focused on the production and characterization of nanocomposite copolyester based films suitable for microwaveable food packaging applications. The matrices selected consist in two PET copolymers modified with carbon black (ULTRA STD) and with titanium oxide (ULTRA NA). Nanocomposite co-extruded multilayer films were produced using different percentages (0%, 2% and 4%wt/wt) of Cloisite 20A (C20A). Films were analyzed for evaluating the effect of nanofiller on the morphology and barrier properties. Moreover, to verify the effectiveness of the designed systems in reducing the cooking times of meat products, MW heating tests were carried out on pork meat hamburgers in MW oven at varying supplied powers. The cooking tests have pointed out that the selected matrices are efficient in reducing cooking times and that even low concentration of C20A acts as heating enhancers of PET

  10. PET based nanocomposite films for microwave packaging applications

    Energy Technology Data Exchange (ETDEWEB)

    Galdi, M. R., E-mail: mrgaldi@unisa.it; Olivieri, R.; Liguori, L.; Albanese, D., E-mail: dalbanese@unisa.it; Di Matteo, M.; Di Maio, L., E-mail: ldimaio@unisa.it [Industrial Engineering Department, University of Salerno, Via Giovanni Paolo II 132, 84084 Fisciano (Italy)

    2015-12-17

    In recent years, changes in life standards have promoted the diffusion of Ready to Cook (RTC) and Ready to Eat (RTE) products for microwave ovens. However, the main limits in microwave (MW) ovens usage are often related to the proper choice of packaging materials suitable for such technology. In fact, packages for microwaveable RTC and RTE foods should ensure adequate preservation of the product before cooking/heating such as high barriers to gases and aromas and adequate control of water vapor transmission. In addition, microwaveable packaging material must be transparent to MW, thermally stable and resistant to the mechanical stress induced by the accumulation in the head space of volatile substances produced during the cooking. Polymeric materials are good candidates for microwaveable packaging thanks to their transparency to MW. In the last years a great interest is devoted to developing innovative solution based on the use of additives or systems that act as susceptors or heating enhancers for improving the characteristics of polymers in cooking/heating in MW ovens. The present work was focused on the production and characterization of nanocomposite copolyester based films suitable for microwaveable food packaging applications. The matrices selected consist in two PET copolymers modified with carbon black (ULTRA STD) and with titanium oxide (ULTRA NA). Nanocomposite co-extruded multilayer films were produced using different percentages (0%, 2% and 4%wt/wt) of Cloisite 20A (C20A). Films were analyzed for evaluating the effect of nanofiller on the morphology and barrier properties. Moreover, to verify the effectiveness of the designed systems in reducing the cooking times of meat products, MW heating tests were carried out on pork meat hamburgers in MW oven at varying supplied powers. The cooking tests have pointed out that the selected matrices are efficient in reducing cooking times and that even low concentration of C20A acts as heating enhancers of PET.

  11. PET based nanocomposite films for microwave packaging applications

    Science.gov (United States)

    Galdi, M. R.; Olivieri, R.; Liguori, L.; Albanese, D.; Di Matteo, M.; Di Maio, L.

    2015-12-01

    In recent years, changes in life standards have promoted the diffusion of Ready to Cook (RTC) and Ready to Eat (RTE) products for microwave ovens. However, the main limits in microwave (MW) ovens usage are often related to the proper choice of packaging materials suitable for such technology. In fact, packages for microwaveable RTC and RTE foods should ensure adequate preservation of the product before cooking/heating such as high barriers to gases and aromas and adequate control of water vapor transmission. In addition, microwaveable packaging material must be transparent to MW, thermally stable and resistant to the mechanical stress induced by the accumulation in the head space of volatile substances produced during the cooking. Polymeric materials are good candidates for microwaveable packaging thanks to their transparency to MW. In the last years a great interest is devoted to developing innovative solution based on the use of additives or systems that act as susceptors or heating enhancers for improving the characteristics of polymers in cooking/heating in MW ovens. The present work was focused on the production and characterization of nanocomposite copolyester based films suitable for microwaveable food packaging applications. The matrices selected consist in two PET copolymers modified with carbon black (ULTRA STD) and with titanium oxide (ULTRA NA). Nanocomposite co-extruded multilayer films were produced using different percentages (0%, 2% and 4%wt/wt) of Cloisite 20A (C20A). Films were analyzed for evaluating the effect of nanofiller on the morphology and barrier properties. Moreover, to verify the effectiveness of the designed systems in reducing the cooking times of meat products, MW heating tests were carried out on pork meat hamburgers in MW oven at varying supplied powers. The cooking tests have pointed out that the selected matrices are efficient in reducing cooking times and that even low concentration of C20A acts as heating enhancers of PET.

  12. The Nanophysics of Electron Emission and Breakdown for High Power Microwave Source

    Science.gov (United States)

    2009-12-21

    coaxial anode/collector. 3.1.2. Formation of  plasma  filaments during w‐band microwave breakdown  Regular, two-dimensional plasma ...Injection Gun ," IEEE Trans. Elec. Devices (May, 2005). 2. Booske, John H., “ Plasma physics and related challenges of millimeter-to-terahertz and...high power microwave (HPM) device technologies by establishing new physical understanding of electron emission/absorption and plasma breakdown

  13. Fracturing of hard rocks by microwave treatment and potential applications in mechanised tunnelling

    OpenAIRE

    YANLONG ZHENG

    2018-01-01

    Extremely hard and abrasive rocks have posed great challenges to mechanical excavators such as tunnel boring machines and roadheaders by increasing the cutter wear and decreasing the penetration rates. Microwave treatment prior to mechanical rock breakage has been recognised as a promising technology. This PhD project measures/derives the dielectric properties of commonly encountered rocks and minerals and investigates the effect of microwave treatment on the physical and mechanical propertie...

  14. DMSP SSM/I- Microwave Imager

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The SSM/I is a seven-channel, four frequency, linearly-polarized, passive microwave radiometric system which measures atmospheric, ocean and terrain microwave...

  15. Microwave Plasma System: PVA Tepla 300

    Data.gov (United States)

    Federal Laboratory Consortium — Description:CORAL Name: Microwave AsherA tool using microwave oxygen plasma to remove organics on the surfacesSpecifications / Capabilities:Frequency: 2.45 GHzPower:...

  16. Digital microwave communication engineering point-to-point microwave systems

    CERN Document Server

    Kizer, George

    2013-01-01

    The first book to cover all engineering aspects of microwave communication path design for the digital age Fixed point-to-point microwave systems provide moderate-capacity digital transmission between well-defined locations. Most popular in situations where fiber optics or satellite communication is impractical, it is commonly used for cellular or PCS site interconnectivity where digital connectivity is needed but not economically available from other sources, and in private networks where reliability is most important. Until now, no book has adequately treated all en

  17. S-band 300 W pulsed solid state microwave amplifier development for driving high power klystrons for electron accelerators

    International Nuclear Information System (INIS)

    Mohania, Praveen; Shrivastava, Purushottam; Hannurkar, P.R.

    2005-01-01

    S-Band Microwave electron accelerators like microtrons and linear accelerators need pulsed microwaves from few megawatts to tens of megawatts to accelerator the electrons to desired energy and intensity. Klystron tube based driver amplifiers were used to drive the high power klystrons, which need microwave power from few tens of watts to 1 kW depending on tube output power and gain. A endeavour was initiated at Centre for Advanced Technology to develop state of art solid state S-band microwave amplifiers indigenously to drive the klystron tubes. A modular design approach was used and individual modules up to 160 W power levels were developed and tested. Finally combining 160 W modules will give up to 300 W output power. Several more modules can be combined to achieve even high power levels. Present paper describes the developmental efforts of 300 W S-band solid-state amplifiers and related microwave technologies. (author)

  18. Superconductivity applications for infrared and microwave devices II; Proceedings of the Meeting, Orlando, FL, Apr. 4, 5, 1991

    Science.gov (United States)

    Heinen, Vernon O.; Bhasin, Kul B.

    Topics discussed include thin-film technology, microwave transmission lines and resonators, microwave devices and circuits, infrared detectors and bolometers, and superconducting junctions. Papers are presented on possible enhancement in bolometric response using free-standing film of YBa2Cu3O(x), aging and surface instability in high-Tc superconductors, epitaxial Tl2Ba2CaCu2O8 thin films on LaAlO3 and their microwave device properties, the performance of stripline resonators using sputtered YBCO films, and a coplanar waveguide microwave filter of YBa2Cu3O7. Attention is also given to the performance characteristics of Y-Ba-Cu-O microwave superconducting detectors, high-Tc bolometer developments for planetary missions, infrared detectors from YBaCuO thin films, high-temperature superconductor junction technology, and submillimeter receiver components using superconducting tunnel junctions. (For individual items see A93-27244 to A93-27248)

  19. [Study on the Emission Spectrum of Hydrogen Production with Microwave Discharge Plasma in Ethanol Solution].

    Science.gov (United States)

    Sun, Bing; Wang, Bo; Zhu, Xiao-mei; Yan, Zhi-yu; Liu, Yong-jun; Liu, Hui

    2016-03-01

    Hydrogen is regarded as a kind of clean energy with high caloricity and non-pollution, which has been studied by many experts and scholars home and abroad. Microwave discharge plasma shows light future in the area of hydrogen production from ethanol solution, providing a new way to produce hydrogen. In order to further improve the technology and analyze the mechanism of hydrogen production with microwave discharge in liquid, emission spectrum of hydrogen production by microwave discharge plasma in ethanol solution was being studied. In this paper, plasma was generated on the top of electrode by 2.45 GHz microwave, and the spectral characteristics of hydrogen production from ethanol by microwave discharge in liquid were being studied using emission spectrometer. The results showed that a large number of H, O, OH, CH, C2 and other active particles could be produced in the process of hydrogen production from ethanol by microwave discharge in liquid. The emission spectrum intensity of OH, H, O radicals generated from ethanol is far more than that generated from pure water. Bond of O-H split by more high-energy particles from water molecule was more difficult than that from ethanol molecule, so in the process of hydrogen production by microwave discharge plasma in ethanol solution; the main source of hydrogen was the dehydrogenation and restructuring of ethanol molecules instead of water decomposition. Under the definite external pressure and temperature, the emission spectrum intensity of OH, H, O radicals increased with the increase of microwave power markedly, but the emission spectrum intensity of CH, C2 active particles had the tendency to decrease with the increase of microwave power. It indicated that the number of high energy electrons and active particles high energy electron energy increased as the increase of microwave power, so more CH, C2 active particles were split more thoroughly.

  20. The role of the native oxide shell on the microwave sintering of copper metal powder compacts

    International Nuclear Information System (INIS)

    Mahmoud, Morsi M.; Link, Guido; Thumm, Manfred

    2015-01-01

    Highlights: • Thin oxide native layer had a critical role on microwave sintering of copper. • Explain why microwaves interact with copper powder differently than its bulk. • Abnormal expansion in copper is due to the plastic deformation and crack formation. • In-situ setup gives important insight about the microwave sintering of metals. • Microwave sintering is a promising candidate technology in powder metallurgy. - Abstract: Successful microwave sintering of several metal powders had been reported by many researchers with remarkable improvements in the materials properties and/or in the overall process. However, the concept behind microwave heating of metal powders has not been fully understood till now, as it is well known that bulk metals reflect microwaves. The progress of microwave sintering of copper metal powder compacts was investigated via combining both in-situ electrical resistivity and dilatometry measurements that give important information about microstructural changes with respect to the inter-particle electrical contacts during sintering. The sintering behavior of copper metal powders was depending on the type of the gas used, particle size, the initial green density, the soaking sintering time and the thin oxide layer on the particles surfaces. The thin copper oxide native layer (ceramics) that thermodynamically formed on the particles surfaces under normal handling and ambient environmental conditions had a very critical and important role in the microwave absorption and interaction, the sintering behavior and the microstructural changes. This finding could help to have a fundamental understanding of why MW’s interact with copper metal powder in a different way than its bulk at room temperature, i.e. why a given metal powder could be heated using microwaves while its bulk reflects it

  1. Final Technical Report Microwave Assisted Electrolyte Cell for Primary Aluminum Production

    Energy Technology Data Exchange (ETDEWEB)

    Xiaodi Huang; J.Y. Hwang

    2007-04-18

    This research addresses the high priority research need for developing inert anode and wetted cathode technology, as defined in the Aluminum Industry Technology Roadmap and Inert Anode Roadmap, with the performance targets: a) significantly reducing the energy intensity of aluminum production, b) ultimately eliminating anode-related CO2 emissions, and c) reducing aluminum production costs. This research intended to develop a new electrometallurgical extraction technology by introducing microwave irradiation into the current electrolytic cells for primary aluminum production. This technology aimed at accelerating the alumina electrolysis reduction rate and lowering the aluminum production temperature, coupled with the uses of nickel based superalloy inert anode, nickel based superalloy wetted cathode, and modified salt electrolyte. Michigan Technological University, collaborating with Cober Electronic and Century Aluminum, conducted bench-scale research for evaluation of this technology. This research included three sub-topics: a) fluoride microwave absorption; b) microwave assisted electrolytic cell design and fabrication; and c) aluminum electrowinning tests using the microwave assisted electrolytic cell. This research concludes that the typically used fluoride compound for aluminum electrowinning is not a good microwave absorbing material at room temperature. However, it becomes an excellent microwave absorbing material above 550°C. The electrowinning tests did not show benefit to introduce microwave irradiation into the electrolytic cell. The experiments revealed that the nickel-based superalloy is not suitable for use as a cathode material; although it wets with molten aluminum, it causes severe reaction with molten aluminum. In the anode experiments, the chosen superalloy did not meet corrosion resistance requirements. A nicked based alloy without iron content could be further investigated.

  2. Compact torus compression of microwaves

    International Nuclear Information System (INIS)

    Hewett, D.W.; Langdon, A.B.

    1985-01-01

    The possibility that a compact torus (CT) might be accelerated to large velocities has been suggested by Hartman and Hammer. If this is feasible one application of these moving CTs might be to compress microwaves. The proposed mechanism is that a coaxial vacuum region in front of a CT is prefilled with a number of normal electromagnetic modes on which the CT impinges. A crucial assumption of this proposal is that the CT excludes the microwaves and therefore compresses them. Should the microwaves penetrate the CT, compression efficiency is diminished and significant CT heating results. MFE applications in the same parameters regime have found electromagnetic radiation capable of penetrating, heating, and driving currents. We report here a cursory investigation of rf penetration using a 1-D version of a direct implicit PIC code

  3. Microwavable thermal energy storage material

    Science.gov (United States)

    Salyer, I.O.

    1998-09-08

    A microwavable thermal energy storage material is provided which includes a mixture of a phase change material and silica, and a carbon black additive in the form of a conformable dry powder of phase change material/silica/carbon black, or solid pellets, films, fibers, moldings or strands of phase change material/high density polyethylene/ethylene vinyl acetate/silica/carbon black which allows the phase change material to be rapidly heated in a microwave oven. The carbon black additive, which is preferably an electrically conductive carbon black, may be added in low concentrations of from 0.5 to 15% by weight, and may be used to tailor the heating times of the phase change material as desired. The microwavable thermal energy storage material can be used in food serving applications such as tableware items or pizza warmers, and in medical wraps and garments. 3 figs.

  4. Microwave Activation of Drug Release

    DEFF Research Database (Denmark)

    Jónasson, Sævar Þór

    Due to current limitations in control of pharmaceutical drug release in the body along with increasing medicine use, methods of externally-controlled drug release are of high interest. In this thesis, the use of microwaves is proposed as a technique with the purpose of externally activating...... setup, called the microwave activation system has been developed and tested on a body phantom that emulates the human torso. The system presented in this thesis, operates unobtrusively, i.e. without physically interfering with the target (patient). The torso phantom is a simple dual-layered cylindrical...... the phantom is of interest for disclosing essential information about the limitations of the concept, the phantom and the system. For these purposes, a twofold operation of the microwave activation system was performed, which are reciprocal of each other. In the first operation phase, named mapping...

  5. Compact Microwave Fourier Spectrum Analyzer

    Science.gov (United States)

    Savchenkov, Anatoliy; Matsko, Andrey; Strekalov, Dmitry

    2009-01-01

    A compact photonic microwave Fourier spectrum analyzer [a Fourier-transform microwave spectrometer, (FTMWS)] with no moving parts has been proposed for use in remote sensing of weak, natural microwave emissions from the surfaces and atmospheres of planets to enable remote analysis and determination of chemical composition and abundances of critical molecular constituents in space. The instrument is based on a Bessel beam (light modes with non-zero angular momenta) fiber-optic elements. It features low power consumption, low mass, and high resolution, without a need for any cryogenics, beyond what is achievable by the current state-of-the-art in space instruments. The instrument can also be used in a wide-band scatterometer mode in active radar systems.

  6. The microwave era is just beginning

    International Nuclear Information System (INIS)

    Grad, P.

    1989-01-01

    Microwave energy applicators in curing rubber products and in ceramic manufacture are enunciated by some of the participants at the First Australian Symposium on Microwave Power Applications held in February 1989 at Wollongong. The advantages and disadvantages of microwave heating over conventional methods are stated

  7. Modeling of microwave heating of metallic powders

    International Nuclear Information System (INIS)

    Buchelnikov, V.D.; Louzguine-Luzgin, D.V.; Anzulevich, A.P.; Bychkov, I.V.; Yoshikawa, N.; Sato, M.; Inoue, A.

    2008-01-01

    As it is known from the experiment that bulk metallic samples reflect microwaves while powdered samples can absorb such a radiation and be heated efficiently. In the present paper we investigate theoretically the mechanisms of penetration of a layer of metallic powder by microwave radiation and microwave heating of such a system

  8. Microwave assisted centrifuge and related methods

    Science.gov (United States)

    Meikrantz, David H [Idaho Falls, ID

    2010-08-17

    Centrifuge samples may be exposed to microwave energy to heat the samples during centrifugation and to promote separation of the different components or constituents of the samples using a centrifuge device configured for generating microwave energy and directing the microwave energy at a sample located in the centrifuge.

  9. 47 CFR 101.141 - Microwave modulation.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Microwave modulation. 101.141 Section 101.141... SERVICES Technical Standards § 101.141 Microwave modulation. (a) Microwave transmitters employing digital modulation techniques and operating below 25.25 GHz (except for MVDDS stations in the 12,200-12,700 MHz band...

  10. Prospects of microwave processing: An overview

    Indian Academy of Sciences (India)

    Administrator

    wave heating. In addition, microwave energy is being explored for the sintering of metal powders also. Ceramic and metal nanopowders have been sintered in microwave. Furthermore, initiatives have been taken to process the amorphous materials (e.g. glass) by microwave heating. Besides this, an attempt has been made ...

  11. Microwave-assisted organic and polymer chemistry

    NARCIS (Netherlands)

    Hoogenboom, R.; Schubert, U.S.

    2009-01-01

    The first ACS symposium on Microwave-Assisted Chemistry: Organic and Polymer Synthesis, held as part of the ACS National meeting in Philadelphia, in August 2008, aimed at various topics of the use of microwave irradiation. The symposium found that specific heating effects, such as higher microwave

  12. Microwave assisted chemical vapor infiltration

    International Nuclear Information System (INIS)

    Devlin, D.J.; Currier, R.P.; Barbero, R.S.; Espinoza, B.F.; Elliott, N.

    1991-01-01

    A microwave assisted process for production of continuous fiber reinforced ceramic matrix composites is described. A simple apparatus combining a chemical vapor infiltration reactor with a conventional 700 W multimode oven is described. Microwave induced inverted thermal gradients are exploited with the ultimate goal of reducing processing times on complex shapes. Thermal gradients in stacks of SiC (Nicalon) cloths have been measured using optical thermometry. Initial results on the ''inside out'' deposition of SiC via decomposition of methyltrichlorosilane in hydrogen are presented. Several key processing issues are identified and discussed. 5 refs

  13. Microwave materials for wireless applications

    CERN Document Server

    Cruickshank, David B

    2011-01-01

    This practical resource offers you an in-depth, up-to-date understanding of the use of microwave magnetic materials for cutting-edge wireless applications. The book discusses device applications used in wireless infrastructure base stations, point-to-point radio links, and a range of more specialized microwave systems. You find detailed discussions on the attributes of each family of magnetic materials with respect to specific wireless applications. Moreover, the book addresses two of the hottest topics in the field today - insertion loss and intermodulation. This comprehensive reference also

  14. Josephson tunnel junction microwave attenuator

    DEFF Research Database (Denmark)

    Koshelets, V. P.; Shitov, S. V.; Shchukin, A. V.

    1993-01-01

    A new element for superconducting electronic circuitry-a variable attenuator-has been proposed, designed, and successfully tested. The principle of operation is based on the change in the microwave impedance of a superconductor-insulator-superconductor (SIS) Josephson tunnel junction when dc biased...... at different points in the current-voltage characteristic. Both numerical calculations based on the Tien-Gordon theory and 70-GHz microwave experiments have confirmed the wide dynamic range (more than 15-dB attenuation for one stage) and the low insertion loss in the ''open'' state. The performance of a fully...

  15. Thermal measurement a requirement for monolithic microwave integrated circuit design

    OpenAIRE

    Hopper, Richard; Oxley, C. H.

    2008-01-01

    The thermal management of structures such as Monolithic Microwave Integrated Circuits (MMICs) is important, given increased circuit packing densities and RF output powers. The paper will describe the IR measurement technology necessary to obtain accurate temperature profiles on the surface of semiconductor devices. The measurement procedure will be explained, including the device mounting arrangement and emissivity correction technique. The paper will show how the measurement technique has be...

  16. The application of microwave techniques to temperature measurement in biotelemetry

    International Nuclear Information System (INIS)

    Glajchen, M.

    1984-01-01

    The use of a microwave dielectric resonator for temperature measurement in Biotelemetry offers the advantage that a passive temperature telemeter can be used. The telemeter is powered by a source remote from the host creature, thus permitting greater miniaturisation of the implant than is possible with conventional techniques. This is essential, especially for application to small animals where the telemeter size and weight become critical. The design of the telemeter which is based upon a novel microwave technique, and the associated practical considerations are discussed. Included in this work is a criticism of initially promising ideas which after an in-depth investigation had to be disregarded. Although the transponder could not be built in its final form due to the unavailability of certain key materials, the transponder operation was tested and found to be successful. A specification of the transponder and transmitter requirements for a working system are included. A theoretical and experimental appraisal of dielectric resonators as miniature microwave filters, also forms a large part of this work. Dielectric resonators offer a significant volume reduction compared to air-filled metallic cavities, and simple coupling to microstrip combined with ease of tuning permits incorporation into Microwave Integrated Circuits. A computer program which can form the basis for a dielectric resonator filter design is provided, and some unusual results of tests on dielectric resonators are presented. It is believed that this will help to popularise and increase understanding of the dielectric resonator - which is an exciting, yet still emerging technology

  17. Continuous vulcanization of extruded profile by microwave process

    International Nuclear Information System (INIS)

    Lim Hun Soo

    1994-01-01

    Continuous vulcanization is being increasingly used today in the manufacture of extrusion profiles. This is particularly so with the microwave/hot air continuous vulcanization process. Although this process is now quite widely used in Europe and to a lesser extent in USA, it is still not used in Malaysia. To improve the technological capability of the rubber-based industry in extrusion product, the RRIM has acquired a microwave/hot air tunnel continuous vulcanization equipment to enable development work in this area to be carried out with the aim of upgrading the rubber industry towards this more automated manufacturing process. This is particularly pertinent in view of the anticipated labour shortage, and, increasing labour and energy cost. This paper outlines the basic principles of operation of the microwave/hot air tunnel continuous vulcanization process and describes some aspects of compounding involving natural and synthetic rubbers for use in the process. As temperature increase is one of the major factors influencing the vulcanization of profile in this process, study was therefore concentrated on the heat generation aspect in the microwave tunnel

  18. Monolithic microwave integrated circuit water vapor radiometer

    Science.gov (United States)

    Sukamto, L. M.; Cooley, T. W.; Janssen, M. A.; Parks, G. S.

    1991-01-01

    A proof of concept Monolithic Microwave Integrated Circuit (MMIC) Water Vapor Radiometer (WVR) is under development at the Jet Propulsion Laboratory (JPL). WVR's are used to remotely sense water vapor and cloud liquid water in the atmosphere and are valuable for meteorological applications as well as for determination of signal path delays due to water vapor in the atmosphere. The high cost and large size of existing WVR instruments motivate the development of miniature MMIC WVR's, which have great potential for low cost mass production. The miniaturization of WVR components allows large scale deployment of WVR's for Earth environment and meteorological applications. Small WVR's can also result in improved thermal stability, resulting in improved calibration stability. Described here is the design and fabrication of a 31.4 GHz MMIC radiometer as one channel of a thermally stable WVR as a means of assessing MMIC technology feasibility.

  19. Microwave-Assisted Extraction for Microalgae: From Biofuels to Biorefinery

    Directory of Open Access Journals (Sweden)

    Rahul Vijay Kapoore

    2018-02-01

    Full Text Available The commercial reality of bioactive compounds and oil production from microalgal species is constrained by the high cost of production. Downstream processing, which includes harvesting and extraction, can account for 70–80% of the total cost of production. Consequently, from an economic perspective extraction technologies need to be improved. Microalgal cells are difficult to disrupt due to polymers within their cell wall such as algaenan and sporopollenin. Consequently, solvents and disruption devices are required to obtain products of interest from within the cells. Conventional techniques used for cell disruption and extraction are expensive and are often hindered by low efficiencies. Microwave-assisted extraction offers a possibility for extraction of biochemical components including lipids, pigments, carbohydrates, vitamins and proteins, individually and as part of a biorefinery. Microwave technology has advanced since its use in the 1970s. It can cut down working times and result in higher yields and purity of products. In this review, the ability and challenges in using microwave technology are discussed for the extraction of bioactive products individually and as part of a biorefinery approach.

  20. Microstructural examination by TEM of WC/Co composites prepared by conventional and Microwave processes

    International Nuclear Information System (INIS)

    Agrawal, D.; Cheng, J.; Papworth, A.J.; Jain, H.; Williams, D.B.

    2001-01-01

    Recently, significant developments and advances have taken place in the field of microwave processing of ceramics, composites and metals. Microwave sintering technology of WC/Co based hard metal parts has been now developed for commercial products. Microwave processed WC/Co parts reportedly have exhibited superior performance over standard parts. Additionally, the microwave process requires only one tenth of the total cycle time employed in a conventional process. Laboratory corrosion and impact resistance tests have proved that microwave processed WC/Co parts are several times more resistant than the conventional parts of the same composition. The scanning transmission electron microscopic (STEM) examination conducted an conventionally and microwave sintered WC/Co samples exhibited remarkable difference in the chemistry of cobalt binder phase. It is understood that the superior mechanical properties of microwave sintered part are due to the pure cobalt phase present at the grain boundary of WC grains, while the conventionally sintered part showed there was substantial inter-alloying of Co with tungsten. (author)

  1. Microwave-induced electrostatic etching: generation of highly reactive magnesium for application in Grignard reagent formation.

    Science.gov (United States)

    van de Kruijs, Bastiaan H P; Dressen, Mark H C L; Meuldijk, Jan; Vekemans, Jef A J M; Hulshof, Lumbertus A

    2010-04-07

    A detailed study regarding the influence of microwave irradiation on the formation of a series of Grignard reagents in terms of rates and selectivities has revealed that these heterogeneous reactions may display a beneficial microwave effect. The interaction between microwaves and magnesium turnings generates violent electrostatic discharges. These discharges on magnesium lead to melting of the magnesium surface, thus generating highly active magnesium particles. As compared to conventional operation the microwave-induced discharges on the magnesium surface lead to considerably shorter initiation times for the insertion of magnesium in selected substrates (i.e. halothiophenes, halopyridines, octyl halides, and halobenzenes). Thermographic imaging and surface characterization by scanning electron microscopy showed that neither selective heating nor a "specific" microwave effect was causing the reduction in initiation times. This novel and straightforward initiation method eliminates the use of toxic and environmentally adverse initiators. Thus, this initiation method limits the formation of by-products. We clearly demonstrated that microwave irradiation enables fast Grignard reagent formation. Therefore, microwave technology is promising for process intensification of Grignard based coupling reactions.

  2. On the existence of and mechanism for microwave-specific reaction rate enhancement.

    Science.gov (United States)

    Dudley, Gregory B; Richert, Ranko; Stiegman, A E

    2015-04-01

    The use of microwave radiation to drive chemical reactions has become ubiquitous in almost all fields of chemistry. In all of these areas it is principally due to rapid and convenient heating resulting in significantly higher rates of reaction, with other advantages including enhanced product selectivity and control of materials properties. Although microwave heating continues to grow as an enabling technology, fundamental research into the nature of microwave heating has not grown at the same rate. In the case of chemical reactions run in homogeneous solution, particularly synthetic organic reactions, there is considerable controversy over the origins of rate enhancement, with a fundamental question being whether there exist microwave-specific effects, distinct from what can be attained under conventional convective heating, that can accelerate a reaction rate. In this Perspective, we discuss unique aspects of microwave heating of molecules in solution and discuss the origin and nature of microwave-specific effects arising from the process of "selective heating" of reactants in solution. Integral to this discussion is work from the field of dielectric relaxation spectroscopy, which provides a model for selective heating by Debye relaxation processes. The Perspective also includes a critical discussion of hypotheses of non-thermal effects (alternatively classified here as resonant processes) and an outline of specific reaction parameters for chemical systems in which microwave-specific Debye relaxation processes can result in observable reaction rate enhancement.

  3. Waste minimization through high-pressure microwave digestion of soils for gross α/β analyses

    International Nuclear Information System (INIS)

    Yaeger, J.S.; Smith, L.L.

    1995-04-01

    As a result of the U.S. Department of Energy's (DOE) environmental restoration and waste management activities, laboratories receive numerous analytical requests for gross α/β analyses. Traditional sample preparation methods for gross α/β analysis of environmental and mixed waste samples require repetitive leaching, which is time consuming and generates large volumes of secondary wastes. An alternative to leaching is microwave digestion. In the past. microwave technology has had limited application in the radiochemical laboratory because of restrictions on sample size resulting from vessel pressure limitations. However, new microwave vessel designs allow for pressures on the order of 11 MPa (1500 psi). A procedure is described in which microwave digestion is used to prepare environmental soil samples for gross α/β analysis. Results indicate that the described procedure meets performance requirements for several soil types and is equivalent to traditional digestion techniques. No statistical differences at the 95% confidence interval exist between the measurement on samples prepared from the hot plate and microwave digestion procedures for those soils tested. Moreover, microwave digestion allows samples to be prepared in a fraction of the time with significantly less acid and with lower potential of cross-contamination. In comparison to the traditional hot plate method, the waste volumes required for the microwave procedure are a factor of 10 lower, while the analyst time for sample processing is at least a factor of three lower

  4. Microwave-assisted acid pretreatment of alkali lignin: Effect on characteristics and pyrolysis behavior.

    Science.gov (United States)

    Duan, Dengle; Ruan, Roger; Wang, Yunpu; Liu, Yuhuan; Dai, Leilei; Zhao, Yunfeng; Zhou, Yue; Wu, Qiuhao

    2018-03-01

    This study performed microwave-assisted acid pretreatment on pure lignin. The effects of microwave temperature, microwave time, and hydrochloric acid concentration on characteristics and pyrolysis behavior of lignin were examined. Results of ultimate analysis revealed better properties of all pretreated samples than those of raw lignin. Fourier transform infrared spectroscopy analysis showed breakage of βO4 bond and aliphatic side chain, decrease in OH groups, and formation of CO groups in pretreatment. Microwave temperature exerted more significant influence on lignin structure. Thermal stability of treated lignin was improved and insensitive to short microwave time and acid concentration under mild conditions. Resulting from improved alkyl-phenols and decreased alkoxy-phenols, microwave-assisted acid pretreatment of lignin yielded bio-oil with excellent quality. Total yield of phenols in pyrolysis vapors (200 °C) improved to 14.15%, whereas that of guaiacols decreased to 22.36%. This study shows that microwave-assisted acid pretreatment is a promising technology for lignin conversion. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Effects of microwave pulse-width damage on a bipolar transistor

    International Nuclear Information System (INIS)

    Ma Zhen-Yang; Chai Chang-Chun; Ren Xing-Rong; Yang Yin-Tang; Chen Bin; Zhao Ying-Bo

    2012-01-01

    This paper presents a theoretical study of the pulse-width effects on the damage process of a typical bipolar transistor caused by high power microwaves (HPMs) through the injection approach. The dependences of the microwave damage power, P, and the absorbed energy, E, required to cause the device failure on the pulse width τ are obtained in the nanosecond region by utilizing the curve fitting method. A comparison of the microwave pulse damage data and the existing dc pulse damage data for the same transistor is carried out. By means of a two-dimensional simulator, ISE-TCAD, the internal damage processes of the device caused by microwave voltage signals and dc pulse voltage signals are analyzed comparatively. The simulation results suggest that the temperature-rising positions of the device induced by the microwaves in the negative and positive half periods are different, while only one hot spot exists under the injection of dc pulses. The results demonstrate that the microwave damage power threshold and the absorbed energy must exceed the dc pulse power threshold and the absorbed energy, respectively. The dc pulse damage data may be useful as a lower bound for microwave pulse damage data. (interdisciplinary physics and related areas of science and technology)

  6. Microwave-assisted degradation of acid orange using a conjugated polymer, polyaniline, as catalyst

    Directory of Open Access Journals (Sweden)

    Ufana Riaz

    2014-01-01

    Full Text Available Microwave-assisted photocatalytic degradation of dyes is one of the emerging technologies for waste water remediation. Microwave effectively accelerates photocatalytic degradation, when microwave electrodeless lamp (MEL substitutes traditional UV lamp as light source. This setup can be extremely simplified if MEL and photocatalyst can be replaced by a catalyst which can work under microwave irradiation in the absence of any light source. The present work reports for the first time degradation of acid orange 7 (AO under microwave irradiation using polyaniline (PANI as catalyst in the absence of any UV lamp as light source. The degradation/decolourization was carried out in neutral acidic and basic media and was monitored spectrophotometrically to evaluate the ability of microwave irradiation to degrade AO. Microwave irradiation showed excellent performance as it completely decolourizes AO dye solution in 10 min. With the advantages of low cost and rapid processing, this novel catalyst is expected to gain promising application in the treatment of various dyestuff wastewaters on a large scale.

  7. Modeling microwave/electron-cloud interaction

    International Nuclear Information System (INIS)

    Mattes, M; Sorolla, E; Zimmermann, F

    2013-01-01

    Starting from the separate codes BI-RME and ECLOUD or PyECLOUD, we are developing a novel joint simulation tool, which models the combined effect of a charged particle beam and of microwaves on an electron cloud. Possible applications include the degradation of microwave transmission in telecommunication satellites by electron clouds; the microwave-transmission techniques being used in particle accelerators for the purpose of electroncloud diagnostics; the microwave emission by the electron cloud itself in the presence of a magnetic field; and the possible suppression of electron-cloud formation in an accelerator by injecting microwaves of suitable amplitude and frequency. A few early simulation results are presented. (author)

  8. Adhesive bonding using variable frequency microwave energy

    Science.gov (United States)

    Lauf, Robert J.; McMillan, April D.; Paulauskas, Felix L.; Fathi, Zakaryae; Wei, Jianghua

    1998-01-01

    Methods of facilitating the adhesive bonding of various components with variable frequency microwave energy are disclosed. The time required to cure a polymeric adhesive is decreased by placing components to be bonded via the adhesive in a microwave heating apparatus having a multimode cavity and irradiated with microwaves of varying frequencies. Methods of uniformly heating various articles having conductive fibers disposed therein are provided. Microwave energy may be selectively oriented to enter an edge portion of an article having conductive fibers therein. An edge portion of an article having conductive fibers therein may be selectively shielded from microwave energy.

  9. Microwave processing of radioactive materials-I

    International Nuclear Information System (INIS)

    White, T.L.; Berry, J.B.

    1989-01-01

    This paper is the first of two papers that reviews the major past and present applications of microwave energy for processing radioactive materials, with particular emphasis on processing radioactive wastes. Microwave heating occurs through the internal friction produced inside a dielectric material when its molecules vibrate in response to an oscillating microwave field. For this presentation, we shall focus on the two FCC-approved microwave frequencies for industrial, scientific, and medical use, 915 and 2450 MHz. Also, because of space limitations, we shall postpone addressing plasma processing of hazardous wastes using microwave energy until a later date. 13 refs., 4 figs

  10. Microwave plasmatrons for giant integrated circuit processing

    Energy Technology Data Exchange (ETDEWEB)

    Petrin, A.B.

    2000-02-01

    A method for calculating the interaction of a powerful microwave with a plane layer of magnetoactive low-pressure plasma under conditions of electron cyclotron resonance is presented. In this paper, the plasma layer is situated between a plane dielectric layer and a plane metal screen. The calculation model contains the microwave energy balance, particle balance, and electron energy balance. The equation that expressed microwave properties of nonuniform magnetoactive plasma is found. The numerical calculations of the microwave-plasma interaction for a one-dimensional model of the problem are considered. Applications of the results for microwave plasmatrons designed for processing giant integrated circuits are suggested.

  11. Ceramic matrix composites by microwave assisted CVI

    International Nuclear Information System (INIS)

    Currier, R.P.; Devlin, D.J.

    1993-01-01

    Chemical vapor infiltration (CVI) processes for producing continuously reinforced ceramic composites are reviewed. Potential advantages of microwave assisted CVI are noted and numerical studies of microwave assisted CVI are reviewed. The models predict inverted thermal gradients in fibrous ceramic preforms subjected to microwave radiation and suggest processing strategies for achieving uniformly dense composites. Comparisons are made to experimental results on silicon-based composite systems. The role played by the relative ability of fiber and matrix to dissipate microwave energy is noted. Results suggest that microwave induced inverted gradients can be exploited to promote inside-out densification. 10 refs., 2 figs

  12. Radiofrequency/Microwave Radiation Biological Effects and Safety Standards: A Review

    Science.gov (United States)

    1994-06-01

    reported that a 50 year old woman had developed cataracts after intermittent exposure to a 2.45 GHz microwave oven. The incident power density levels were...include: Survelance, Communications, Command and Control, Intelligence, Signal Processing, Computer Sience and Technology, Electrom Technology, Photoracs and laiity Saences. S* I l I

  13. The Physics of Superconducting Microwave Resonators

    Science.gov (United States)

    Gao, Jiansong

    Over the past decade, low temperature detectors have brought astronomers revolutionary new observational capabilities and led to many great discoveries. Although a single low temperature detector has very impressive sensitivity, a large detector array would be much more powerful and are highly demanded for the study of more difficult and fundamental problems in astronomy. However, current detector technologies, such as transition edge sensors and superconducting tunnel junction detectors, are difficult to integrate into a large array. The microwave kinetic inductance detector (MKID) is a promising new detector technology invented at Caltech and JPL which provides both high sensitivity and an easy solution to the detector integration. It senses the change in the surface impedance of a superconductor as incoming photons break Cooper pairs, by using high-Q superconducting microwave resonators capacitively coupled to a common feedline. This architecture allows thousands of detectors to be easily integrated through passive frequency domain multiplexing. In this thesis, we explore the rich and interesting physics behind these superconducting microwave resonators. The first part of the thesis discusses the surface impedance of a superconductor, the kinetic inductance of a superconducting coplanar waveguide, and the circuit response of a resonator. These topics are related with the responsivity of MKIDs. The second part presents the study of the excess frequency noise that is universally observed in these resonators. The properties of the excess noise, including power, temperature, material, and geometry dependence, have been quantified. The noise source has been identified to be the two-level systems in the dielectric material on the surface of the resonator. A semi-empirical noise model has been developed to explain the power and geometry dependence of the noise, which is useful to predict the noise for a specified resonator geometry. The detailed physical noise

  14. Microwaves and chemical synthesis

    International Nuclear Information System (INIS)

    Parodi, F.

    1999-01-01

    The article summarizes, through some key references, the most important aspects of the theme, focusing, in particular, on the achievable advantages by the application of this clean and efficient technology (whose big potentialities open wide future developments) to the fields of polymerization processes and organic syntheses [it

  15. Microwave Atmospheric-Pressure Sensor

    Science.gov (United States)

    Flower, D. A.; Peckham, G. E.; Bradford, W. J.

    1986-01-01

    Report describes tests of microwave pressure sounder (MPS) for use in satellite measurements of atmospheric pressure. MPS is multifrequency radar operating between 25 and 80 GHz. Determines signal absorption over vertical path through atmosphere by measuring strength of echoes from ocean surface. MPS operates with cloud cover, and suitable for use on current meteorological satellites.

  16. ULTRARAPID VACUUM-MICROWAVE HISTOPROCESSING

    NARCIS (Netherlands)

    KOK, LP; BOON, ME

    A novel histoprocessing method for paraffin sections is presented in which the combination of vacuum and microwave exposure is the key element. By exploiting the decrease in boiling temperature under vacuum, the liquid molecules in the tissues have been successfully extracted and exchanged at

  17. Microwave Oven Repair. Teacher Edition.

    Science.gov (United States)

    Smreker, Eugene

    This competency-based curriculum guide for teachers addresses the skills a technician will need to service microwave ovens and to provide customer relations to help retain the customer's confidence in the product and trust in the service company that performs the repair. The guide begins with a task analysis, listing 20 cognitive tasks and 5…

  18. The Cosmic Microwave Background Anisotropy

    Science.gov (United States)

    Bennett, C. L.

    1994-12-01

    The properties of the cosmic microwave background radiation provide unique constraints on the history and evolution of the universe. The first detection of anisotropy of the microwave radiation was reported by the COBE Team in 1992, based on the first year of flight data. The latest analyses of the first two years of COBE data are reviewed in this talk, including the amplitude of the microwave anisotropy as a function of angular scale and the statistical nature of the fluctuations. The two-year results are generally consistent with the earlier first year results, but the additional data allow for a better determination of the key cosmological parameters. In this talk the COBE results are compared with other observational anisotropy results and directions for future cosmic microwave anisotropy observations will be discussed. The National Aeronautics and Space Administration/Goddard Space Flight Center (NASA/GSFC) is responsible for the design, development, and operation of the Cosmic Background Explorer (COBE). Scientific guidance is provided by the COBE Science Working Group.

  19. Microwave Sensors for Breast Cancer Detection.

    Science.gov (United States)

    Wang, Lulu

    2018-02-23

    Breast cancer is the leading cause of death among females, early diagnostic methods with suitable treatments improve the 5-year survival rates significantly. Microwave breast imaging has been reported as the most potential to become the alternative or additional tool to the current gold standard X-ray mammography for detecting breast cancer. The microwave breast image quality is affected by the microwave sensor, sensor array, the number of sensors in the array and the size of the sensor. In fact, microwave sensor array and sensor play an important role in the microwave breast imaging system. Numerous microwave biosensors have been developed for biomedical applications, with particular focus on breast tumor detection. Compared to the conventional medical imaging and biosensor techniques, these microwave sensors not only enable better cancer detection and improve the image resolution, but also provide attractive features such as label-free detection. This paper aims to provide an overview of recent important achievements in microwave sensors for biomedical imaging applications, with particular focus on breast cancer detection. The electric properties of biological tissues at microwave spectrum, microwave imaging approaches, microwave biosensors, current challenges and future works are also discussed in the manuscript.

  20. Engineering aspect of the microwave ionosphere nonlinear interaction experiment (MINIX) with a sounding rocket

    Science.gov (United States)

    Nagatomo, Makoto; Kaya, Nobuyuki; Matsumoto, Hiroshi

    The Microwave Ionosphere Nonlinear Interaction Experiment (MINIX) is a sounding rocket experiment to study possible effects of strong microwave fields in case it is used for energy transmission from the Solar Power Satellite (SPS) upon the Earth's atmosphere. Its secondary objective is to develop high power microwave technology for space use. Two rocket-borne magnetrons were used to emit 2.45 GHz microwave in order to make a simulated condition of power transmission from an SPS to a ground station. Sounding of the environment radiated by microwave was conducted by the diagnostic package onboard the daughter unit which was separated slowly from the mother unit. The main design drivers of this experiment were to build such high power equipments in a standard type of sounding rocket, to keep the cost within the budget and to perform a series of experiments without complete loss of the mission. The key technology for this experiment is a rocket-borne magnetron and high voltage converter. Location of position of the daughter unit relative to the mother unit was a difficult requirement for a spin-stabilized rocket. These problems were solved by application of such a low cost commercial products as a magnetron for microwave oven and a video tape recorder and camera.

  1. Entanglement concentration and purification of two-mode squeezed microwave photons in circuit QED

    Science.gov (United States)

    Zhang, Hao; Alsaedi, Ahmed; Hayat, Tasawar; Deng, Fu-Guo

    2018-04-01

    We present a theoretical proposal for a physical implementation of entanglement concentration and purification protocols for two-mode squeezed microwave photons in circuit quantum electrodynamics (QED). First, we give the description of the cross-Kerr effect induced between two resonators in circuit QED. Then we use the cross-Kerr media to design the effective quantum nondemolition (QND) measurement on microwave-photon number. By using the QND measurement, the parties in quantum communication can accomplish the entanglement concentration and purification of nonlocal two-mode squeezed microwave photons. We discuss the feasibility of our schemes by giving the detailed parameters which can be realized with current experimental technology. Our work can improve some practical applications in continuous-variable microwave-based quantum information processing.

  2. High-power microwave generation from a frequency-stabilized virtual cathode source

    International Nuclear Information System (INIS)

    Fazio, M.V.; Hoeberling, R.F.; Kinross-Wright, J.

    1988-01-01

    The evolution of virtual cathode based high-power microwave-source technology has been directed primarily toward achieving higher peak-power levels. As peak powers in excess of 10 GW have been reported, attention has begun to focus on techniques for producing a more frequency- and phase-stable virtual cathode source. Free-running virtual cathode microwave sources characteristically exhibit bandwidths in a single pulse of tens of percent, which makes them unsuitable for many applications such as power sources for phased array antennas and microwave linear accelerators. Presented here are results of an experimental approach utilizing a high-Q, resonant cavity surrounding the oscillating virtual cathode to achieve frequency stabilization and repeatable narrow-band operation. A cylindrical cavity resonator is used with the microwave power being extracted radially through circumferential slot apertures into L-band waveguide

  3. Comparison of microwave and conduction-convection heating autohydrolysis pretreatment for bioethanol production.

    Science.gov (United States)

    Aguilar-Reynosa, Alejandra; Romaní, Aloia; Rodríguez-Jasso, Rosa M; Aguilar, Cristóbal N; Garrote, Gil; Ruiz, Héctor A

    2017-11-01

    This work describes the application of two forms of heating for autohydrolysis pretreatment on isothermal regimen: conduction-convection heating and microwave heating processing using corn stover as raw material for bioethanol production. Pretreatments were performed using different operational conditions: residence time (10-50 min) and temperature (160-200°C) for both pretreatments. Subsequently, the susceptibility of pretreated solids was studied using low enzyme loads, and high substrate loads. The highest conversion was 95.1% for microwave pretreated solids. Also solids pretreated by microwave heating processing showed better ethanol conversion in simultaneous saccharification and fermentation process (92% corresponding to 33.8g/L). Therefore, microwave heating processing is a promising technology in the pretreatment of lignocellulosic materials. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Possibilities of utilizing used moulding and core sands by microwave treatment

    Directory of Open Access Journals (Sweden)

    K. Granat

    2011-01-01

    Full Text Available The paper presents a semi-industrial reactor designed for microwave utilization of waste moulds and cores made of moulding sandsprepared in furane resin technology. It was found that a possibility exists of effective incinerating this way prepared residues of coresseparated from moulding sands or waste moulds left after casting. The preliminary tests evidenced that microwave heating is an effectiveway of disposing waste moulding sands and the applied apparatus permits effective control of the microwave heating process. The special structure permitting rotations of charge material and proper selection of the generators working cycles guarantee significant speeding-up the process and its full stabilisation. Application of microwave heating for utilization of waste moulds and cores containing synthetic resins as binders ensures significant and measurable economical benefits resulting from shorter process time.

  5. Impact of Microwave Treatment on Chemical Constituents in Fresh Rhizoma Gastrodiae (Tianma by UPLC-MS Analysis

    Directory of Open Access Journals (Sweden)

    Qimeng Fan

    2014-01-01

    Full Text Available Fresh Rhizoma Gastrodiae (Tianma was processed in a microwave oven at 2450 MHz in order to study the effect on the main chemical component changes taking place during microwave treatment. It was found that microwave affected the chemical composition of Tianma. Seven compounds, including gastrodin, gastrodigenin (p-hydroxybenzylalcohol, p-hydroxybenzaldehyde, vanillyl alcohol, vanillin, adenine, and 5-hydroxymethylfurfural, were identified in this study. As major active compounds, the contents of gastrodin and gastrodigenin in MWT Tianma were both twice as much as those in raw Tianma. Besides, the MS data show that there are still some unidentified compositions in Tianma, and there are also many converted compounds in MWT Tianma, which is worthy of further work. The results have indicated that microwave treated fresh Tianma might be helpful in designing the processing of traditional Chinese medicine and the application of microwave technology in traditional Chinese medicine needs to be researched further in the future.

  6. Delivering Microwave Spectroscopy to the Masses: a Design of a Low-Cost Microwave Spectrometer Operating in the 18-26 GHZ Frequency Range

    Science.gov (United States)

    Steber, Amanda; Pate, Brooks

    2014-06-01

    Advances in chip-level microwave technology in the communications field have led to the possibilities of low cost alternatives for current Fourier transform microwave (FTMW) spectrometers. Many of the large, expensive microwave components in a traditional design can now be replaced by robust, mass market monolithic microwave integrated circuits (MMICs). "Spectrometer on a board" designs are now feasible that offer dramatic cost reduction for microwave spectroscopy. These chip-level components can be paired with miniature computers to produce compact instruments that are operable through USB. A FTMW spectrometer design using the key MMIC components that drive cost reduction will be presented. Two dual channel synthesizers (Valon Technology Model 5008), a digital pattern generator (Byte Paradigm Wav Gen Xpress), and a high-speed digitizer/arbitrary waveform generator combination unit (Tie Pie HS-5 530 XM) form the key components of the spectrometer for operation in the 18-26.5 GHz range. The design performance is illustrated using a spectrometer that is being incorporated into a museum display for astrochemistry. For this instrument a user interface, developed in Python, has been developed and will be shown.

  7. Microwave SQUID multiplexer demonstration for cosmic microwave background imagers

    Science.gov (United States)

    Dober, B.; Becker, D. T.; Bennett, D. A.; Bryan, S. A.; Duff, S. M.; Gard, J. D.; Hays-Wehle, J. P.; Hilton, G. C.; Hubmayr, J.; Mates, J. A. B.; Reintsema, C. D.; Vale, L. R.; Ullom, J. N.

    2017-12-01

    Key performance characteristics are demonstrated for the microwave superconducting quantum interference device (SQUID) multiplexer (μmux) coupled to transition edge sensor (TES) bolometers that have been optimized for cosmic microwave background (CMB) observations. In a 64-channel demonstration, we show that the μmux produces a white, input referred current noise level of 29 pA/ √{H z } at a microwave probe tone power of -77 dB, which is well below the expected fundamental detector and photon noise sources for a ground-based CMB-optimized bolometer. Operated with negligible photon loading, we measure 98 pA/ √{H z } in the TES-coupled channels biased at 65% of the sensor normal resistance. This noise level is consistent with that predicted from bolometer thermal fluctuation (i.e., phonon) noise. Furthermore, the power spectral density is white over a range of frequencies down to ˜100 mHz, which enables CMB mapping on large angular scales that constrain the physics of inflation. Additionally, we report cross-talk measurements that indicate a level below 0.3%, which is less than the level of cross-talk from multiplexed readout systems in deployed CMB imagers. These measurements demonstrate the μmux as a viable readout technique for future CMB imaging instruments.

  8. Microwave SQUID Multiplexer Demonstration for Cosmic Microwave Background Imagers.

    Science.gov (United States)

    Dober, B; Becker, D T; Bennett, D A; Bryan, S A; Duff, S M; Gard, J D; Hays-Wehle, J P; Hilton, G C; Hubmayr, J; Mates, J A B; Reintsema, C D; Vale, L R; Ullom, J N

    2017-12-01

    Key performance characteristics are demonstrated for the microwave SQUID multiplexer (µmux) coupled to transition edge sensor (TES) bolometers that have been optimized for cosmic microwave background (CMB) observations. In a 64-channel demonstration, we show that the µmux produces a white, input referred current noise level of [Formula: see text] at -77 dB microwave probe tone power, which is well below expected fundamental detector and photon noise sources for a ground-based CMB-optimized bolometer. Operated with negligible photon loading, we measure [Formula: see text] in the TES-coupled channels biased at 65% of the sensor normal resistance. This noise level is consistent with that predicted from bolometer thermal fluctuation (i.e. phonon) noise. Furthermore, the power spectral density is white over a range of frequencies down to ~ 100 mHz, which enables CMB mapping on large angular scales that constrain the physics of inflation. Additionally, we report cross-talk measurements that indicate a level below 0.3%, which is less than the level of cross-talk from multiplexed readout systems in deployed CMB imagers. These measurements demonstrate the µmux as a viable readout technique for future CMB imaging instruments.

  9. Optimization of the imaging response of scanning microwave microscopy measurements

    Energy Technology Data Exchange (ETDEWEB)

    Sardi, G. M.; Lucibello, A.; Proietti, E.; Marcelli, R., E-mail: romolo.marcelli@imm.cnr.it [National Research Council, Institute for Microelectronics and Microsystems, Via del Fosso del Cavaliere 100, 00133 Rome (Italy); Kasper, M.; Gramse, G. [Biophysics Institute, Johannes Kepler University, Gruberstrasse 40, 4020 Linz (Austria); Kienberger, F. [Keysight Technologies Austria GmbH, Gruberstrasse 40, 4020 Linz (Austria)

    2015-07-20

    In this work, we present the analytical modeling and preliminary experimental results for the choice of the optimal frequencies when performing amplitude and phase measurements with a scanning microwave microscope. In particular, the analysis is related to the reflection mode operation of the instrument, i.e., the acquisition of the complex reflection coefficient data, usually referred as S{sub 11}. The studied configuration is composed of an atomic force microscope with a microwave matched nanometric cantilever probe tip, connected by a λ/2 coaxial cable resonator to a vector network analyzer. The set-up is provided by Keysight Technologies. As a peculiar result, the optimal frequencies, where the maximum sensitivity is achieved, are different for the amplitude and for the phase signals. The analysis is focused on measurements of dielectric samples, like semiconductor devices, textile pieces, and biological specimens.

  10. Microwave dielectric absorption spectroscopy aiming at novel dosimetry using DNAs

    Energy Technology Data Exchange (ETDEWEB)

    Izumi, Yoshinobu; Hirayama, Makoto; Matuo, Youichirou [Research Institute of Nuclear Engineering, University of Fukui, Fukui (Japan); Sunagawa, Takeyoshi [Fukui University of Technology, Fukui (Japan)

    2017-03-15

    We are developing L-band and S-band microwave dielectric absorption systems aiming novel dosimetry using DNAs, such as plasmid DNA and genomic DNA, and microwave technology. Each system is composed of a cavity resonator, analog signal generator, circulator, power meter, and oscilloscope. Since the cavity resonator is sensitive to temperature change, we have made great efforts to prevent the fluctuation of temperature. We have developed software for controlling and measurement. By using this system, we can measure the resonance frequency, f, and ΔQ (Q is a dimensionless parameter that describes how under-damped an oscillator or resonator is, and characterizes a resonator’s bandwidth relative to its center frequency) within about 3 minutes with high accuracy. This system will be expected to be applicable to DNAs evaluations and to novel dosimetric system.

  11. Monodisperse Silver Nanoparticles Synthesized by a Microwave-Assisted Method

    International Nuclear Information System (INIS)

    Shao-Peng, Zhu; Shao-Chun, Tang; Xiang-Kang, Meng

    2009-01-01

    Silver nanoparticles with an average size of about 20 nm are synthesized in a colloidal solution with the aid of microwave irradiation. Neither additional reductant nor stabilizer is required in this microwave-assisted method. The color of the colloidal solution is found to be dark green, different from the characteristic yellow of silver colloidal solutions. The silver nanoparticles in the colloidal solution have a narrow size distribution and large yield quantity. UV-visible absorption spectroscopy analysis reveals that the as-synthesized monodisperse silver nanoparticles have exceptional optical properties. Raman spectroscopy measurements demonstrate that these silver nanoparticles exhibit a notable surface-enhanced Raman scattering ability. (cross-disciplinary physics and related areas of science and technology)

  12. A heat mathematical model of polymer composite cylinder during microwave treatment

    Directory of Open Access Journals (Sweden)

    S. V. Reznik

    2014-01-01

    Full Text Available Traditional technologies of producing epoxy based polymer composite materials (PCM require a long-term and energy consuming thermal processing. Microwave heating could be used as an alternative technology for heating work pieces made of PCM; this would allow to reduce treatment time and energy consumption significantly. A mathematical model of temperature distribution inside a cylindrical composite system during microwave treatment was investigated in this paper. The model includes a hollow PCM cylinder made of an epoxy binder and carbon fibers and a solid cylindrical mandrel. Theoretical and experimental results on the temperature state of the system were analyzed and discussed.

  13. Cosmic microwave background polarization results from QUIET

    International Nuclear Information System (INIS)

    Buder, I.

    2014-01-01

    Despite the success of precision cosmology, cosmologists cannot fully explain the initial conditions of the Universe. Inflation, an exponential expansion in the first ∼ 10 -36 s, is a promising potential explanation. A generic prediction of inflation is odd-parity (B-mode) polarization in the cosmic microwave background (CMB). Q/U Imaging Experiment (QUIET) aimed at limiting or detecting this polarization. We built a pseudo-correlation microwave polarimeter as an array of mass-produced modules in the focal plane of a 1.4 m telescope. We used rotation around the absorbing ground screen, a new time-stream double-demodulation technique, and optimized optics in the design to reduce instrumental polarization. We observed with this instrument at the Atacama Plateau in Chile between October 2008 and December 2010. This paper describes the analysis and results of these observations from one of 2 parallel pipelines. We developed noise modeling, filtering and data selection following a blind-analysis strategy. Central to this strategy was a suite of null test, each motivated by a possible instrumental problem or systematic effect. We evaluated the systematic errors in the blind stage of the analysis before the result was known. We calculated the CMB power spectra using a pseudo-C l cross-correlation technique that suppressed contamination and made the result insensitive to noise bias. We measured the first 3 peaks of the E-mode spectrum at high significance and limited B-mode polarization. We measured the CMB polarization power at 25 ≤ l ≤ 975. We found no statistically significant deviation from ΛCDM model, and our results are consistent with zero BB and EB power. Systematic errors were well below our B-mode polarization limits. This systematic-error reduction was a strong demonstration of technology for application in more sensitive, next generation CMB experiments. (author)

  14. The cosmic microwave background radiation

    International Nuclear Information System (INIS)

    Wilson, R.W.

    1980-01-01

    The history is described of the discovery of microwave radiation of the cosmic background using the 20-foot horn antenna at the Bell Laboratories back in 1965. Ruby masers with travelling wave were used, featuring the lowest noise in the world. The measurement proceeded on 7 cm. In measuring microwave radiation from the regions outside the Milky Way continuous noise was discovered whose temperature exceeded the calculated contributions of the individual detection system elements by 3 K. A comparison with the theory showed that relict radiation from the Big Bang period was the source of the noise. The discovery was verified by measurements on the 20.1 cm wavelength and by other authors' measurements on 0.5 mm to 74 cm, and by optical measurements of the interstellar molecule spectrum. (Ha)

  15. Tapping mode microwave impedance microscopy

    KAUST Repository

    Lai, K.

    2009-01-01

    We report tapping mode microwave impedance imaging based on atomic force microscope platforms. The shielded cantilever probe is critical to localize the tip-sample interaction near the tip apex. The modulated tip-sample impedance can be accurately simulated by the finite-element analysis and the result agrees quantitatively to the experimental data on a series of thin-film dielectric samples. The tapping mode microwave imaging is also superior to the contact mode in that the thermal drift in a long time scale is totally eliminated and an absolute measurement on the dielectric properties is possible. We demonstrated tapping images on working nanodevices, and the data are consistent with the transport results. © 2009 American Institute of Physics.

  16. Interstitial microwave hyperthermia treatment investigations

    International Nuclear Information System (INIS)

    Siauve, N; Lormel, C

    2012-01-01

    Microwave ablation also called interstitial hyperthermia is a medical procedure used in the treatment of many cancers, cardiac arrhythmias and other medical conditions. With this medical therapy, an electromagnetic source (antenna) is directly positioned in the target tissue and a sufficient power is injected to necrosis the tissue. The aim of this study is to propose a design procedure and develop the associated tools, for determining the optimal shape, dimensions, type and operating frequency of antenna according to the target volume. In this context, a 3D numerical predictive model of temperature elevation induced by the electric fields and two benches for thermal and electrical tissues properties characterization have been developed. To validate the procedure and the different tools, an experimental bench test which includes interstitial antenna, external microwave generator, phantom that represents the target tissue and measurement system of temperature and electric field has been elaborated.

  17. Multikilowatt variable frequency microwave furnace

    International Nuclear Information System (INIS)

    Bible, D.W.; Lauf, R.J.; Everleigh, C.A.

    1992-01-01

    In this paper, the authors describe a new type of microwave processing furnace in which the frequency can be varied continuously from 4 to 8 GHz and the power level varied from zero up to 2.5 kW. The extraordinary bandwidth of this furnace is achieved by using a traveling wave tube (TWT) amplifier originally developed for electronic warfare applications. The TWT is a linear beam device characterized by a traveling electromagnetic wave that continuously extracts energy longitudinally along the path of an electron beam. The TWT, unlike other microwave tubes such as the magnetron, klystron, gyrotron, and others, does not depend upon resonant RF fields and is therefore capable of wide bandwidth operation.operation

  18. HERMA-Heartbeat Microwave Authentication

    Science.gov (United States)

    Lux, James Paul (Inventor); Chow, Edward (Inventor); McKee, Michael Ray (Inventor); Haque, Salman-ul Mohammed (Inventor); Tkacenko, Andre (Inventor)

    2018-01-01

    Systems and methods for identifying and/or authenticating individuals utilizing microwave sensing modules are disclosed. A HEaRtbeat Microwave Authentication (HERMA) system can enable the active identification and/or authentication of a user by analyzing reflected RF signals that contain a person's unique characteristics related to their heartbeats. An illumination signal is transmitted towards a person where a reflected signal captures the motion of the skin and tissue (i.e. displacement) due to the person's heartbeats. The HERMA system can utilize existing transmitters in a mobile device (e.g. Wi-Fi, Bluetooth, Cellphone signals) as the illumination source with at least one external receive antenna. The received reflected signals can be pre-processed and analyzed to identify and/or authenticate a user.

  19. Interactions of microwave with plasmas

    International Nuclear Information System (INIS)

    Zhang Haifeng; Shao Fuqiu; Wang Long

    2003-01-01

    When plasma size scale is comparable with the wavelength of electromagnetic waves, W.K.B. solution isn't applicable. In this paper a new numerical solution technique to investigate interactions of microwave with plasmas is presented by using Runge-Kutta method. The results of numerical solution coincide with that of analytical solution while the model is linear electron density profile in calculated accuracy

  20. Comparative microstructure study of oil palm fruit bunch fibre, mesocarp and kernels after microwave pre-treatment

    Science.gov (United States)

    Chang, Jessie S. L.; Chan, Y. S.; Law, M. C.; Leo, C. P.

    2017-07-01

    The implementation of microwave technology in palm oil processing offers numerous advantages; besides elimination of polluted palm oil mill effluent, it also reduces energy consumption, processing time and space. However, microwave exposure could damage a material’s microstructure which affected the quality of fruit that can be related to its physical structure including the texture and appearance. In this work, empty fruit bunches, mesocarp and kernel was microwave dried and their respective microstructures were examined. The microwave pretreatments were conducted at 100W and 200W and the microstructure investigation of both treated and untreated samples were evaluated using scanning electron microscope. The micrographs demonstrated that microwave does not significantly influence kernel and mesocarp but noticeable change was found on the empty fruit bunches where the sizes of the granular starch were reduced and a small portion of the silica bodies were disrupted. From the experimental data, the microwave irradiation was shown to be efficiently applied on empty fruit bunches followed by mesocarp and kernel as significant weight loss and size reduction was observed after the microwave treatments. The current work showed that microwave treatment did not change the physical surfaces of samples but sample shrinkage is observed.

  1. Microwave heating for male contraception

    International Nuclear Information System (INIS)

    Jiang, H.B.

    1985-01-01

    A study at Sichuan University investigated microwave irradiation as a reversible male contraception. In the first phase of the study, the testes of rabbits were exposed to 2450 MHz microwaves with intensity of 15-35 mW/cm/sup 2/ for 15-20 minutes. The animals' sperm count was reduced from 5.86 x 10/sup 8/ +- 1.67 x 10/sup 8//ml (S.D.), to 0.273 x 10/sup 8/ +- 0.385 x 10/sup -8//ml 35 days after exposure. The impregnation ability was lost for about two months, even though the animals retained a normal sexual desire and physical condition. In the second phase, a group of 200 human volunteers received 2450 MHz microwave exposure with an intensity of 80-100 mW/cm/sup 2/ at the surface of the scrotum for 40-60 minutes. The volunteers' sperm counts were reduced from 7511 x 10/sup 4/ +- 2758 x 10/sup 4//ml to 366 x 10/sup 4/ +- 352 x 10/sup 4//ml at 39 +- 5.4 days after exposure; reduction amounting to approximately 95 percent. The viability and motility of the sperm were also reduced. Two months after the last exposure, the sperm counts of the volunteers recovered to 4625 x 10/sup 4/ +- 1897 x 10/sup 4//ml. No obvious changes were found either in medical examinations or in the daily lifestyles of the volunteers

  2. Microwave photonics systems based on whispering-gallery-mode resonators.

    Science.gov (United States)

    Coillet, Aurélien; Henriet, Rémi; Phan Huy, Kien; Jacquot, Maxime; Furfaro, Luca; Balakireva, Irina; Larger, Laurent; Chembo, Yanne K

    2013-08-05

    Microwave photonics systems rely fundamentally on the interaction between microwave and optical signals. These systems are extremely promising for various areas of technology and applied science, such as aerospace and communication engineering, sensing, metrology, nonlinear photonics, and quantum optics. In this article, we present the principal techniques used in our lab to build microwave photonics systems based on ultra-high Q whispering gallery mode resonators. First detailed in this article is the protocol for resonator polishing, which is based on a grind-and-polish technique close to the ones used to polish optical components such as lenses or telescope mirrors. Then, a white light interferometric profilometer measures surface roughness, which is a key parameter to characterize the quality of the polishing. In order to launch light in the resonator, a tapered silica fiber with diameter in the micrometer range is used. To reach such small diameters, we adopt the "flame-brushing" technique, using simultaneously computer-controlled motors to pull the fiber apart, and a blowtorch to heat the fiber area to be tapered. The resonator and the tapered fiber are later approached to one another to visualize the resonance signal of the whispering gallery modes using a wavelength-scanning laser. By increasing the optical power in the resonator, nonlinear phenomena are triggered until the formation of a Kerr optical frequency comb is observed with a spectrum made of equidistant spectral lines. These Kerr comb spectra have exceptional characteristics that are suitable for several applications in science and technology. We consider the application related to ultra-stable microwave frequency synthesis and demonstrate the generation of a Kerr comb with GHz intermodal frequency.

  3. Development of a Microwave Regenerative Sorbent-Based Hydrogen Purifier

    Science.gov (United States)

    Wheeler, Richard R., Jr.; Dewberry, Ross H.; McCurry, Bryan D.; Abney, Morgan B.; Greenwood, Zachary W.

    2016-01-01

    This paper describes the design and fabrication of a Microwave Regenerative Sorbent-based Hydrogen Purifier (MRSHP). This unique microwave powered technology was developed for the purification of a hydrogen stream produced by the Plasma Pyrolysis Assembly (PPA). The PPA is a hydrogen recovery (from methane) post processor for NASA's Sabatier-based carbon dioxide reduction process. Embodied in the Carbon dioxide Reduction Assembly (CRA), currently aboard the International Space Station (ISS), the Sabatier reaction employs hydrogen to catalytically recover oxygen, in the form of water, from respiratory carbon dioxide produced by the crew. This same approach is base-lined for future service in the Air Revitalization system on extended missions into deep space where resupply is not practical. Accordingly, manned exploration to Mars may only become feasible with further closure of the air loop as afforded by the greater hydrogen recovery permitted by the PPA with subsequent hydrogen purification. By utilizing the well-known high sorbate loading capacity of molecular sieve 13x, coupled with microwave dielectric heating phenomenon, MRSHP technology is employed as a regenerative filter for a contaminated hydrogen gas stream. By design, freshly regenerated molecular sieve 13x contained in the MRSHP will remove contaminants from the effluent of a 1-CM scale PPA for several hours prior to breakthrough. By reversing flow and pulling a relative vacuum the MRSHP prototype then uses 2.45 GHz microwave power, applied through a novel coaxial antenna array, to rapidly heat the sorbent bed and drive off the contaminants in a short duration vacuum/thermal contaminant desorption step. Finally, following rapid cooling via room temperature cold plates, the MRSHP is again ready to serve as a hydrogen filter.

  4. Microwave studies of gas discharge plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Brown, S C [Department of Physics and the Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, MA (United States)

    1958-07-01

    The plasma diagnostics in absence and in presence of magnetic field is discussed. It is concluded that it is not possible, even for low electron densities, to obtain a general theory in a form suitable for experimental verification and use in the microwave diagnostics of magnetized plasma, and valid for all possible configurations of the microwave field. Consequently, only a few special configurations of the microwave field are analysed.

  5. Microwave processing in MOX fuel cycle

    International Nuclear Information System (INIS)

    Mallik, G.K.; Malav, R.K.; Panakkal, J.P.; Kamath, H.S.

    2005-01-01

    The prominent aspect of the microwave heating technique applications in nuclear material processing is its eco-friendly status. It is envisaged that no active liquid waste will be generated from microwave processing. AFFF has fabricated the (U, Pu) 2 O mixed oxide fuels for PHWRs, BWRs and PFBR. AFFF is also working for the AHWR fuel cycle. The present paper summarises about the process experiments, instrumental development, results, and future applications of microwave heating technique. (author)

  6. Harmonic distortion in microwave photonic filters.

    Science.gov (United States)

    Rius, Manuel; Mora, José; Bolea, Mario; Capmany, José

    2012-04-09

    We present a theoretical and experimental analysis of nonlinear microwave photonic filters. Far from the conventional condition of low modulation index commonly used to neglect high-order terms, we have analyzed the harmonic distortion involved in microwave photonic structures with periodic and non-periodic frequency responses. We show that it is possible to design microwave photonic filters with reduced harmonic distortion and high linearity even under large signal operation.

  7. Techniques for ceramic sintering using microwave energy

    International Nuclear Information System (INIS)

    Kimrey, H.D.; Janney, M.A.; Becher, P.F.

    1987-01-01

    The use of microwave energy for ceramic sintering offers exciting new possibilities for materials processing. Based on experience gathered in microwave processing associated with the heating of fusion plasmas, we have developed hardware and methods for uniformly heating ceramic parts of large volume and irregular shape to temperatures in excess of 1600 0 C, in vacuum or pressurized atmosphere. Microwave processing at 28 GHz yields enhanced densification rates with a corresponding reduction in sintering temperatures. 6 refs

  8. Microwave generation and complex microwave responsivity measurements on small Dayem bridges

    DEFF Research Database (Denmark)

    Pedersen, Niels Falsig; Sørensen, O; Mygind, Jesper

    1977-01-01

    Measurements of the active properties of a Dayem micro-bridge at X-band frequencies is described. The bridge was mounted in a microwave cavity designed to match the bridge properly and the microwave output from the cavity was detected using a sensitive X-band spectrometer. Microwave power...

  9. Flexible composite via rapid titania coating by microwave-assisted ...

    Indian Academy of Sciences (India)

    2017-06-09

    Jun 9, 2017 ... carbon fibre via microwave-assisted hydrothermal synthesis (MHS) ... Nanoparticles; titanium dioxide; microwave-assisted hydrothermal synthesis; carbon fibre. ..... study, the carbon fibre absorbs microwave radiation and con-.

  10. TRMM MICROWAVE IMAGER (TMI) WENTZ OCEAN PRODUCTS V3

    Data.gov (United States)

    National Aeronautics and Space Administration — The TRMM Microwave Imager (TMI) is a 5-channel, dual-polarized, passive microwave radiometer. Microwave radiation is emitted by the Earth's surface and by water...

  11. Freeze dehydration of milk using microwave energy

    International Nuclear Information System (INIS)

    Souda, K.B.; Akyel, C.; Bilgen, E.

    1989-01-01

    This paper presents the results of experimental studies on heat and mass transfer during a microwave freeze dehydration process. An experimental system and procedure was developed to freeze dry milk. A 2500-W microwave system with an appropriate wave guide was set up and instrumented, and a procedure was experimentally developed to obtain milk powder first by freezing milk and then dehydrating it at low pressure using microwave energy. An unsteady-state analysis was used to derive a one-dimensional mathematical model of the freeze dehydration process in a microwave electromagnetic field

  12. Continuous microwave flow synthesis of mesoporous hydroxyapatite

    Energy Technology Data Exchange (ETDEWEB)

    Akram, Muhammad; Alshemary, Ammar Z.; Goh, Yi-Fan; Wan Ibrahim, Wan Aini [Department of Chemistry, Universiti Teknologi Malaysia, 81310 UTM Johor Bahru, Johor (Malaysia); Lintang, Hendrik O. [Centre for Sustainable Nanomaterials (CSNano), Ibnu Sina Institute for Scientific and Industrial Research, Universiti Teknologi Malaysia, 81310 UTM Johor Bahru, Johor (Malaysia); Hussain, Rafaqat, E-mail: rafaqat@kimia.fs.utm.my [Centre for Sustainable Nanomaterials (CSNano), Ibnu Sina Institute for Scientific and Industrial Research, Universiti Teknologi Malaysia, 81310 UTM Johor Bahru, Johor (Malaysia)

    2015-11-01

    We have successfully used continuous microwave flow synthesis (CMFS) technique for the template free synthesis of mesoporous hydroxyapatite. The continuous microwave flow reactor consisted of a modified 2.45 GHz household microwave, peristaltic pumps and a Teflon coil. This cost effective and efficient system was exploited to produce semi-crystalline phase pure nano-sized hydroxyapatite. Effect of microwave power, retention time and the concentration of reactants on the phase purity, degree of crystallinity and surface area of the final product was studied in detail. X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) were used to study the phase purity and composition of the product, while transmission electron microscopy (TEM) was used to study the effect of process parameters on the morphology of hydroxyapatite. The TEM analysis confirmed the formation of spherical particles at low microwave power; however the morphology of the particles changed to mesoporous needle and rod-like structure upon exposing the reaction mixture to higher microwave power and longer retention time inside the microwave. The in-vitro ion dissolution behavior of the as synthesized hydroxyapatite was studied by determining the amount of Ca{sup 2+} ion released in SBF solution. - Highlights: • Continuous microwave flow synthesis method was used to prepare hydroxyapatite. • Increase in microwave power enhanced the degree of crystallinity. • TEM images confirmed the presence of mesopores on the surface of HA.

  13. Continuous microwave flow synthesis of mesoporous hydroxyapatite

    International Nuclear Information System (INIS)

    Akram, Muhammad; Alshemary, Ammar Z.; Goh, Yi-Fan; Wan Ibrahim, Wan Aini; Lintang, Hendrik O.; Hussain, Rafaqat

    2015-01-01

    We have successfully used continuous microwave flow synthesis (CMFS) technique for the template free synthesis of mesoporous hydroxyapatite. The continuous microwave flow reactor consisted of a modified 2.45 GHz household microwave, peristaltic pumps and a Teflon coil. This cost effective and efficient system was exploited to produce semi-crystalline phase pure nano-sized hydroxyapatite. Effect of microwave power, retention time and the concentration of reactants on the phase purity, degree of crystallinity and surface area of the final product was studied in detail. X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) were used to study the phase purity and composition of the product, while transmission electron microscopy (TEM) was used to study the effect of process parameters on the morphology of hydroxyapatite. The TEM analysis confirmed the formation of spherical particles at low microwave power; however the morphology of the particles changed to mesoporous needle and rod-like structure upon exposing the reaction mixture to higher microwave power and longer retention time inside the microwave. The in-vitro ion dissolution behavior of the as synthesized hydroxyapatite was studied by determining the amount of Ca 2+ ion released in SBF solution. - Highlights: • Continuous microwave flow synthesis method was used to prepare hydroxyapatite. • Increase in microwave power enhanced the degree of crystallinity. • TEM images confirmed the presence of mesopores on the surface of HA

  14. Microwave Photonic Imaging Radiometer, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Passive Microwave Remote Sensing is currently utilized by NASA, NOAA, and USGIS to conduct Earth Science missions, including weather forecasting, early warning...

  15. Controlled Microwave Heating Accelerates Rolling Circle Amplification.

    Directory of Open Access Journals (Sweden)

    Takeo Yoshimura

    Full Text Available Rolling circle amplification (RCA generates single-stranded DNAs or RNA, and the diverse applications of this isothermal technique range from the sensitive detection of nucleic acids to analysis of single nucleotide polymorphisms. Microwave chemistry is widely applied to increase reaction rate as well as product yield and purity. The objectives of the present research were to apply microwave heating to RCA and indicate factors that contribute to the microwave selective heating effect. The microwave reaction temperature was strictly controlled using a microwave applicator optimized for enzymatic-scale reactions. Here, we showed that microwave-assisted RCA reactions catalyzed by either of the four thermostable DNA polymerases were accelerated over 4-folds compared with conventional RCA. Furthermore, the temperatures of the individual buffer components were specifically influenced by microwave heating. We concluded that microwave heating accelerated isothermal RCA of DNA because of the differential heating mechanisms of microwaves on the temperatures of reaction components, although the overall reaction temperatures were the same.

  16. Refraction and absorption of microwaves in wood

    International Nuclear Information System (INIS)

    Ziherl, Saša; Bajc, Jurij; Čepič, Mojca

    2013-01-01

    A demonstration experiment for physics students showing the dependence of the refractive index and absorption coefficient of wood on the direction of microwaves is presented. Wood and microwaves enable study of anisotropic properties, which are typically found in crystals. Wood is used as the persuasive representative of uniaxial anisotropic materials due to its visible structure and its consequent anisotropic properties. Wood can be cut in a general direction and wooden plates a few centimetres thick with well-defined fibre orientation are easily prepared. Microwaves are used because wood is transparent for microwaves and their centimetre-scale wavelength is comparable to the wood structure. (paper)

  17. Microwave oscillator with 'whispering gallery' resonator

    International Nuclear Information System (INIS)

    Kirichenko, A.Ya.; Prokopenko, Yu.V.; Filippov, Yu.F.; Lonin, Yu.F.; Papkovich, V.G.; Ponomarev, A.G.; Prokopenko, Yu.V.; Uvarov, V.T.

    2010-01-01

    It was presented researches of a generation of microwave radiation into system with azimuthally periodical relativistic electron beam current that excites a high-Q quasi-optical dielectric resonator. The Eigen parameters of cylindrical Teflon resonator were determined by numerical computation. Registration of the microwave radiation realizes by a crystal set of 8-mm wavelength range. Research projects of microwave oscillators with high-Q resonators, in which 'whispering gallery' oscillations are excited by an electron flow, are presented. Multiresonator oscillators ideology is based on principles of microwave generation in klystrons with both subcritical and supercritical electron beams currents.

  18. Influence of voltage rise time on microwave generation in relativistic backward wave oscillator

    International Nuclear Information System (INIS)

    Wu, Ping; Deng, Yuqun; Sun, Jun; Teng, Yan; Shi, Yanchao; Chen, Changhua

    2015-01-01

    In relativistic backward wave oscillators (RBWOs), although the slow wave structure (SWS) and electron beam determine the main characteristics of beam-wave interaction, many other factors can also significantly affect the microwave generation process. This paper investigates the influence of voltage rise time on beam-wave interaction in RBWOs. Preliminary analysis and PIC simulations demonstrate if the voltage rise time is moderately long, the microwave frequency will gradually increase during the startup process until the voltage reaches its amplitude, which can be explained by the dispersion relation. However, if the voltage rise time is long enough, the longitudinal resonance of the finitely-long SWS will force the RBWO to work with unwanted longitudinal modes for a while and then gradually hop to the wanted longitudinal mode, and this will lead to an impure microwave frequency spectrum. Besides, a longer voltage rise time will delay the startup process and thus lead to a longer microwave saturation time. And if unwanted longitudinal modes are excited due to long voltage rise time, the microwave saturation time will be further lengthened. Therefore, the voltage rise time of accelerators adopted in high power microwave technology should not be too long in case unwanted longitudinal modes are excited

  19. A comparative study of infrared and microwave heating for microbial decontamination of paprika powder

    Directory of Open Access Journals (Sweden)

    Lovisa eEliasson

    2015-09-01

    Full Text Available There is currently a need in developing new decontamination technologies for spices due to limitations of existing technologies, mainly regarding their effects on spices’ sensory quality. In the search of new decontamination solutions, it is of interest to compare different technologies, to provide the industry with knowledge for taking decisions concerning appropriate decontamination technologies for spices. The present study compares infrared and microwave decontamination of naturally contaminated paprika powder after adjustment of water activity to 0.88. Infrared respectively microwave heating was applied to quickly heat up paprika powder to 98°C, after which the paprika sample was transferred to a conventional oven set at 98°C to keep the temperature constant during a holding time up to 20 min. In the present experimental set-up microwave treatment at 98°C for 20 min resulted in a reduction of 4.8 log units of the total number of mesophilic bacteria, while the infrared treatment showed a 1 log unit lower reduction for the corresponding temperature and treatment time. Microwave and infrared heating created different temperature profiles and moisture distribution within the paprika sample during the heating up part of the process, which is likely to have influenced the decontamination efficiency. The results of this study are used to discuss the difficulties in comparing two thermal technologies on equal conditions due to differences in their heating mechanisms.

  20. AMSR-E/Aqua Monthly Global Microwave Land Surface Emissivity

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set is a global land emissivity product using passive microwave observations from the Advanced Microwave Scanning Radiometer - Earth Observing System...

  1. An efficient chemical analysis of phenolic acids and flavonoids in raw propolis by microwave-assisted extraction combined with high-performance liquid chromatography using the fused-core technology.

    Science.gov (United States)

    Pellati, Federica; Prencipe, Francesco Pio; Bertelli, Davide; Benvenuti, Stefania

    2013-01-01

    A closed-vessel microwave-assisted extraction (MAE) technique was optimized for the first time for the extraction of polyphenols from raw propolis. The results obtained by means of response surface experimental design methodology showed that the best global response was reached when the extraction temperature was set at 106 °C, the solvent composition close to EtOH-H2O 80:20 (v/v), with an extraction time of 15 min. In comparison with other techniques, such as maceration, heat reflux extraction (HRE) and ultrasound-assisted extraction (UAE), the extraction with MAE was improved by shorter extraction time and lower volume of solvent needed. The HPLC analyses of propolis extracts were carried out on a fused-core Ascentis Express C18 column (150 mm × 3.0 mm I.D., 2.7 μm), with a gradient mobile phase composed by 0.1% formic acid in water and acetonitrile. Detection was performed by DAD and MS. The method validation indicated that the correlation coefficients were >0.999; the limit of detection was in the range 0.5-0.8 μg/ml for phenolic acids and 1.2-3.0 μg/ml for flavonoids; the recovery range was 95.3-98.1% for phenolic acids and 94.1-101.3% for flavonoids; the intra- and inter-day %RSD values for retention times and peak areas were ≤ 0.3 and 2.2%, respectively. The quali- and quantitative analysis of polyphenols in Italian samples of raw propolis was performed with the validated method. Total phenolic acids ranged from 5.0 to 120.8 mg/g and total flavonoids from 2.5 to 168.0mg/g. The proposed MAE procedure and HPLC method can be considered reliable and useful tools for the comprehensive multi-component analysis of polyphenols in propolis extracts to be used in apitherapy. Copyright © 2013 Elsevier B.V. All rights reserved.

  2. Microwave pyrolysis for conversion of materials to energy : A review

    International Nuclear Information System (INIS)

    Mokhtar, M.; Omar, R.; MOhammad Salleh, M.A.; Idris, A.

    2009-01-01

    Full text: The disposal of wastes in Malaysia is becoming a serious problem in many industrialized and public sectors. This is due to the high production of waste such as municipal solid waste, sludge from waste water treatment plants, agricultural waste and other used non-biodegradable products such as plastics and tyres. These wastes although are reused as compost, fuel, recycled and so on, there are still abundant left. These leftovers pose problems such as heavy metal leaching, leachates, green house gas emissions and mosquito breeding grounds. The disposal cost of these wastes sometimes can be costly at up to RM 2,200/ ton such as petroleum sludge by Kualiti Alam. Several methods have been used to convert these residues to energy via thermal treatment such as combustion, incineration and gasification. However, pyrolysis becomes one of the popular methods as the alternative to the wastes disposal recently. Not only energy (as gas) is produced, by-products such as chemical feedstock and solid absorbent can be produced. The use of microwave for pyrolysis, although relatively new for waste treatment, has several advantages compared to conventional heating. This includes easy control of the heating process, time saving, higher heating efficiency, etc. Tyre microwave pyrolysis plant in UK is known as the earliest plant using microwave technology to breakdown polymer in used tyres. Since 1990s, there are many patents for microwave pyrolysis. The processes are based on microwave pyrolysis of waste include coffee hulls, wood, coal, sewage sludge, hospital waste, plastic wastes, corn cobs and rice straw. The most important factors influencing the yield of product during the pyrolysis is temperature in range from 500 to 1000 degree Celsius according to product preference. High temperature favors gas products; whereas lower temperature favors liquid products. Comparatively, microwave pyrolysis produced gas with higher hydrogen and carbon monoxide (syngas) content compared

  3. Microwave Atmospheric Sounder on CubeSat

    Science.gov (United States)

    Padmanabhan, S.; Brown, S. E.; Kangaslahti, P.; Cofield, R.; Russell, D.; Stachnik, R. A.; Su, H.; Wu, L.; Tanelli, S.; Niamsuwan, N.

    2014-12-01

    To accurately predict how the distribution of extreme events may change in the future we need to understand the mechanisms that influence such events in our current climate. Our current observing system is not well-suited for observing extreme events globally due to the sparse sampling and in-homogeneity of ground-based in-situ observations and the infrequent revisit time of satellite observations. Observations of weather extremes, such as extreme precipitation events, temperature extremes, tropical and extra-tropical cyclones among others, with temporal resolution on the order of minutes and spatial resolution on the order of few kms (cost passive microwave sounding and imaging sensors on CubeSats that would work in concert with traditional flagship observational systems, such as those manifested on large environmental satellites (i.e. JPSS,WSF,GCOM-W), to monitor weather extremes. A 118/183 GHz sensor would enable observations of temperature and precipitation extremes over land and ocean as well as tropical and extra-tropical cyclones. This proposed project would enable low cost, compact radiometer instrumentation at 118 and 183 GHz that would fit in a 6U Cubesat with the objective of mass-producing this design to enable a suite of small satellites to image the key geophysical parameters needed to improve prediction of extreme weather events. We take advantage of past and current technology developments at JPL viz. HAMSR (High Altitude Microwave Scanning Radiometer), Advanced Component Technology (ACT'08) to enable low-mass, low-power high frequency airborne radiometers. In this paper, we will describe the design and implementation of the 118 GHz temperature sounder and 183 GHz humidity sounder on the 6U CubeSat. In addition, a summary of radiometer calibration and retrieval techniques of temperature and humidity will be discussed. The successful demonstration of this instrument on the 6U CubeSat would pave the way for the development of a constellation which

  4. Investigation of microwave melting and vitrification of nuclear wastes

    International Nuclear Information System (INIS)

    Silve, J.M.

    1996-10-01

    This work deals with the treatment process of long-lived alpha-emitting wastes, developed by the CEA, and consisting of incinerating these wastes and of vitrifying the obtained ashes by micro-waves. In this study is at first presented the materials to characterize (incineration ashes, glasses) followed by measurements of their electric permittivity. A description of the melting furnace DEMW (Densification by Micro-Waves) is given as well as its electromagnetic characterization. The inductive heating of the molten glass by micro-waves has been revealed in this part. The modeling of the power transfer to the molten glass is then presented. It is based on a sectoring of the furnace in terms of the natural weakening of each of the three areas. With this model can be obtained a general formula of the power dissipated in the molten glass in terms of the attenuation and of the position of the short-circuit piston. The fourth part relates the melt tests of different glasses and is based on the technological improvements carried out in the furnace and coming from modeling. A correlation between the modeling and the tests results is proposed. A brief characterization of the obtained material allows to verify that its qualities are acceptable particularly for leaching. (O.M.)

  5. On-chip microwave circulators using quantum Hall plasmonics

    Science.gov (United States)

    Mahoney, Alice; Colless, James; Pauka, Sebastian; Hornibrook, John; Doherty, Andrew; Reilly, David; Peeters, Lucas; Fox, Eli; Goldhaber-Gordon, David; Kou, Xuefeng; Pan, Lei; Wang, Kang; Watson, John; Gardner, Geoffrey; Manfra, Michael

    Circulators are directional circuit elements integral to technologies including radar systems, microwave communication transceivers and the readout of quantum information devices. Their non-reciprocity commonly arises from the interference of microwaves over the centimetre-scale of the signal wavelength in the presence of bulky magnetic media that breaks time-reversal symmetry. We present a completely passive on-chip microwave circulator with size 1/1000th the wavelength by exploiting the chiral, `slow-light' response of a GaAs/AlGaAs 2-dimensional electron gas in the quantum Hall regime. Further, by implementing this circulator design on a thin film of a magnetic topological insulator (Cr0.12(Bi0.26Sb0.62)2Te3), we show that similar non-reciprocity can be achieved at zero magnetic field. This additional mode of operation serves as a non-invasive probe of edge states in the quantum anomalous Hall effect, while also extending the possibility for integration with superconducting devices.

  6. Biologic effects of electromagnetic radiation and microwave

    International Nuclear Information System (INIS)

    Deng Hua

    2002-01-01

    Electromagnetic radiation and microwave exist mankind's environment widely. People realize they disserve authors' health when authors make use of them. Electromagnetic radiation is one of the major physic factors which injure people's health. A review of the biologic mechanism about electromagnetic radiation and microwave, their harmful effects to human body, problems in authors' research and the prospect

  7. Pyrolysis of methane by microwaves. Pt. 1

    International Nuclear Information System (INIS)

    Avni, R.; Winefordner, J.D.; Nickel, H.

    1975-04-01

    The pyrolysis of methane and mixtures of argon-methane by microwaves (2,450 MHz) was investigated. The microwave plasma diagnostic study was performed using electrical probes, namely, the double floating probe technique. Parameters such as electric field strength and current densities were measured and from their relationship the electron temperature, electric conductivity, electron and ion densities were evaluated as function of gas pressure, microwave power input and distance of the probe from the microwave cavity. Various spectroscopic techniques were used for the measurement of temperatures in the microwave plasma; the 'reversal temperature' by measuring the intensities of the electronic vibrational bands of CN and OH molecules and 'rotational temperature' from the measured intensities of rotational OH lines. The 'rotational' as well as the 'reversal temperature' were found to be identical and this temperature was assumed to be the temperature of the gas in the microwave plasma. Energy balance calculation, based upon the electrical energy input and thermal losses, were performed in order to determine if steady state conditions existed in the microwave plasma. Emission and absorption spectroscopy were used for determining the active species formed in the pyrolysis of methane and also of mixtures of CH 4 -Ar, by the microwave plasma. (orig.) [de

  8. A microwave-augmented plasma torch module

    International Nuclear Information System (INIS)

    Kuo, S P; Bivolaru, Daniel; Williams, Skip; Carter, Campbell D

    2006-01-01

    A new plasma torch device which combines arc and microwave discharges to enhance the size and enthalpy of the plasma torch is described. A cylindrical-shaped plasma torch module is integrated into a tapered rectangular cavity to form a microwave adaptor at one end, which couples the microwave power injected into the cavity from the other end to the arc plasma generated by the torch module. A theoretical study of the microwave coupling from the cavity to the plasma torch, as the load, is presented. The numerical results indicate that the microwave power coupling efficiency exceeds 80%. Operational tests of the device indicate that the microwave power is coupled to the plasma torch and that the arc discharge power is increased. The addition of microwave energy enhances the height, volume and enthalpy of the plasma torch when the torch operates at a low airflow rate, and even when the flow speed is supersonic, a noticeable microwave effect on the plasma torch is observed. In addition, the present design allows the torch to be operated as both a fuel injector and igniter. Ignition of ethylene fuel injected through the centre of a tungsten carbide tube acting as the central electrode is demonstrated

  9. Vanishing microwave effects : influence of heterogeneity

    NARCIS (Netherlands)

    Dressen, M.H.C.L.; Kruijs, van de B.H.P.; Meuldijk, J.; Vekemans, J.A.J.M.; Hulshof, L.A.

    2007-01-01

    A consistent setup of experiments has been conducted to demonstrate an enhanced reaction rate under microwave irradiation as compared to conventional heating, i.e. a real microwave effect. It was found that addition of a cosolvent, diminishing the heterogeneous character of the reaction mixture,

  10. A Synthesizable Multicore Platform for Microwave Imaging

    DEFF Research Database (Denmark)

    Schleuniger, Pascal; Karlsson, Sven

    2014-01-01

    Active microwave imaging techniques such as radar and tomography are used in a wide range of medical, industrial, scientific, and military applications. Microwave imaging devices emit radio waves and process their reflections to reconstruct an image. However, data processing remains a challenge...

  11. Anisotropy of Wood in the Microwave Region

    Science.gov (United States)

    Ziherl, Sasa; Bajc, Jurij; Urankar, Bernarda; Cepic, Mojca

    2010-01-01

    Wood is transparent for microwaves and due to its anisotropic structure has anisotropic dielectric properties. A laboratory experiment that allows for the qualitative demonstration and quantitative measurements of linear dichroism and birefringence in the microwave region is presented. As the proposed experiments are based on the anisotropy (of…

  12. Microwave Radiometer Systems, Design and Analysis

    DEFF Research Database (Denmark)

    Skou, Niels; Vine, David Le

    Two important microwave remote sensors are the radar and the radiometer. There have been a number of books written on various aspects of radar, but there have been only a few written on microwave radiometers, especially on subjects of how to design and build radiometer systems. This book, which...

  13. Tunable Water-based Microwave Metasurface

    DEFF Research Database (Denmark)

    Kapitanova, Polina; Odit, Mikhail; Dobrykh, Dmitry

    2017-01-01

    A water-based dynamically tunable microwave metasurface is developed and experimentally investigated. A simple approach to tune the metasurface properties by changing the shape of water-based unit cells by gravitation force is proposed. The transmission spectra of the metasurface for linear...... angle. The proposed approach can be used to design cheap metasurfaces for electromagnetic wave control in the microwave frequency range....

  14. Microwave bale moisture sensing: Field trial

    Science.gov (United States)

    A microwave moisture measurement technique was developed for moisture sensing of cotton bales after the bale press. The technique measures the propagation delay of a microwave signal that is transmitted through the cotton bale. This research conducted a field trial to test the sensor in a commercial...

  15. Microwave bale moisture sensing: Field trial continued

    Science.gov (United States)

    A microwave moisture measurement technique was developed at the USDA, ARS Cotton Production and Processing Research Unit for moisture sensing of cotton bales after the bale press. The technique measures the propagation delay of a microwave signal that is transmitted through the cotton bale. This res...

  16. A new integrated microwave SQUID circuit design

    International Nuclear Information System (INIS)

    Erne, S.N.; Finnegan, T.F.

    1980-01-01

    In this paper we consider the design and operation of a planar thin-film rf-SQUID circuit which can be realized via microwave-integrated-circuit (MIC) techniques and which differs substantially from pervious microwave SQUID configurations involving either mechanical point-contact or cylindrical thin-film micro-bridge geometries. (orig.)

  17. Microwave dielectric properties of nanostructured nickel ferrite

    Indian Academy of Sciences (India)

    Wintec

    Abstract. Nickel ferrite is one of the important ferrites used in microwave devices. In the present work, we have synthesized nanoparticles of nickel ferrite using chemical precipitation technique. The crystal structure and grain size of the particles are studied using XRD. The microwave dielectric properties of nanostructured.

  18. Organic Synthesis Using Microwaves and Supported Reagents

    Science.gov (United States)

    In the electromagnetic radiation region, microwaves (0.3GHz-300GHz) lie between radiowave (Rf) and infrared (IR) frequencies with relatively large wavelengths (1 mm-1 m). Microwaves, non-ionizing radiation incapable of breaking bonds, are a form of energy that manifest as heat t...

  19. Electromagnetic and microwave absorbing properties of hollow ...

    Indian Academy of Sciences (India)

    bandwidth below −10 dB and minimum RL decrease with increasing thickness of HCNSs/paraffin composites. Keywords. Nanomaterials; nanospheres; CVD; electric; magnetic; microwave absorption properties. 1. Introduction. In recent years, microwave absorbing materials have attracted considerable attention because it ...

  20. System design development for microwave and millimeter-wave materials processing

    Science.gov (United States)

    Feher, Lambert; Thumm, Manfred

    2002-06-01

    The most notable effect in processing dielectrics with micro- and millimeter-waves is volumetric heating of these materials, offering the opportunity of very high heating rates for the samples. In comparison to conventional heating where the heat transfer is diffusive and depends on the thermal conductivity of the material, the microwave field penetrates the sample and acts as an instantaneous heat source at each point of the sample. By this unique property, microwave heating at 2.45 GHz and 915 MHz ISM (Industrial, Medical, Scientific) frequencies is established as an important industrial technology since more than 50 years ago. Successful application of microwaves in industries has been reported e.g. by food processing systems, domestic ovens, rubber industry, vacuum drying etc. The present paper shows some outlines of microwave system development at Forschungszentrum Karlsruhe, IHM by transferring properties from the higher frequency regime (millimeter-waves) to lower frequency applications. Anyway, the need for using higher frequencies like 24 GHz (ISM frequency) for industrial applications has to be carefully verified with respect to special physical/engineering advantages or to limits the standard microwave technology meets for the specific problem.

  1. Wide gap semiconductor microwave devices

    International Nuclear Information System (INIS)

    Buniatyan, V V; Aroutiounian, V M

    2007-01-01

    A review of properties of wide gap semiconductor materials such as diamond, diamond-like carbon films, SiC, GaP, GaN and AlGaN/GaN that are relevant to electronic, optoelectronic and microwave applications is presented. We discuss the latest situation and perspectives based on experimental and theoretical results obtained for wide gap semiconductor devices. Parameters are taken from the literature and from some of our theoretical works. The correspondence between theoretical results and parameters of devices is critically analysed. (review article)

  2. Multiband rectenna for microwave applications

    Science.gov (United States)

    Okba, Abderrahim; Takacs, Alexandru; Aubert, Hervé; Charlot, Samuel; Calmon, Pierre-François

    2017-02-01

    This paper reports a multiband rectenna (rectifier + antenna) suitable for the electromagnetic energy harvesting of the spill-over loss of microwave antennas placed on board of geostationary satellites. Such rectenna is used for powering autonomous wireless sensors for satellite health monitoring. The topology of the rectenna is presented. The experimental results demonstrate that the proposed compact rectenna can harvest efficiently the incident electromagnetic energy at three different frequencies that are close to the resonant frequencies of the cross-dipoles implemented in the antenna array. xml:lang="fr"

  3. The Microwave Temperature Profiler (PERF)

    Science.gov (United States)

    Lim, Boon; Mahoney, Michael; Haggerty, Julie; Denning, Richard

    2013-01-01

    The JPL developed Microwave Temperature Profiler (MTP) has recently participated in GloPac, HIPPO (I to V) and TORERO, and the ongoing ATTREX campaigns. The MTP is now capable of supporting the NASA Global Hawk and a new canister version supports the NCAR G-V. The primary product from the MTP is remote measurements of the atmospheric temperature at, above and below the flight path, providing for the vertical state of the atmosphere. The NCAR-MTP has demonstrated unprecedented instrument performance and calibration with plus or minus 0.2 degrees Kelvin flight level temperature error. Derived products include curtain plots, isentropes, lapse rate, cold point height and tropopause height.

  4. Design of microwave active devices

    CERN Document Server

    Gautier , Jean-Luc

    2014-01-01

    This book presents methods for the design of the main microwave active devices. The first chapter focuses on amplifiers working in the linear mode. The authors present the problems surrounding narrowband and wideband impedance matching, stability, polarization and the noise factor, as well as specific topologies such as the distributed amplifier and the differential amplifier. Chapter 2 concerns the power amplifier operation. Specific aspects on efficiency, impedance matching and class of operation are presented, as well as the main methods of linearization and efficiency improvement. Freq

  5. Digital readouts for large microwave low-temperature detector arrays

    International Nuclear Information System (INIS)

    Mazin, Benjamin A.; Day, Peter K.; Irwin, Kent D.; Reintsema, Carl D.; Zmuidzinas, Jonas

    2006-01-01

    Over the last several years many different types of low-temperature detectors (LTDs) have been developed that use a microwave resonant circuit as part of their readout. These devices include microwave kinetic inductance detectors (MKID), microwave SQUID readouts for transition edge sensors (TES), and NIS bolometers. Current readout techniques for these devices use analog frequency synthesizers and IQ mixers. While these components are available as microwave integrated circuits, one set is required for each resonator. We are exploring a new readout technique for this class of detectors based on a commercial-off-the-shelf technology called software defined radio (SDR). In this method a fast digital to analog (D/A) converter creates as many tones as desired in the available bandwidth. Our prototype system employs a 100MS/s 16-bit D/A to generate an arbitrary number of tones in 50MHz of bandwidth. This signal is then mixed up to the desired detector resonant frequency (∼10GHz), sent through the detector, then mixed back down to baseband. The baseband signal is then digitized with a series of fast analog to digital converters (80MS/s, 14-bit). Next, a numerical mixer in a dedicated integrated circuit or FPGA mixes the resonant frequency of a specified detector to 0Hz, and sends the complex detector output over a computer bus for processing and storage. In this paper we will report on our results in using a prototype system to readout a MKID array, including system noise performance, X-ray pulse response, and cross-talk measurements. We will also discuss how this technique can be scaled to read out many thousands of detectors

  6. Understanding the microwave annealing of silicon

    Directory of Open Access Journals (Sweden)

    Chaochao Fu

    2017-03-01

    Full Text Available Though microwave annealing appears to be very appealing due to its unique features, lacking an in-depth understanding and accurate model hinder its application in semiconductor processing. In this paper, the physics-based model and accurate calculation for the microwave annealing of silicon are presented. Both thermal effects, including ohmic conduction loss and dielectric polarization loss, and non-thermal effects are thoroughly analyzed. We designed unique experiments to verify the mechanism and extract relevant parameters. We also explicitly illustrate the dynamic interaction processes of the microwave annealing of silicon. This work provides an in-depth understanding that can expedite the application of microwave annealing in semiconductor processing and open the door to implementing microwave annealing for future research and applications.

  7. Influence of microwaves on olive oil stability

    International Nuclear Information System (INIS)

    Farag, R.S.; El-Baroty, G.; Abd El-Aziz, N.; Basuny, A.M.

    1997-01-01

    The fruits of Picual and Shemlalli olive cultivars were exposed to microwaves generated from an oven at low and moderate power settings for 3, 6, 9 and 12 min. The physicochemical constants and fatty acid composition of the olive oil samples extracted from nonmicrowaved and microwaved fruits were determined. The data demonstrated that microwaves did not alter the values of the above mentioned parameters compared with the oil extracted from nonmicrowaved fruits. Quality assurance tests (acid, peroxide and TBA values) elucidated that microwaves generally increased the olive oil stability of Picual and Shemlalli cultivars during storage. In addition, microwaves generated from oven ot moderate power setting for 12 min. exhibited an antioxidant power on olive oil equivalent to that possessed by BHT at 200 ppm [es

  8. Polymer coated fiber Bragg grating thermometry for microwave hyperthermia.

    Science.gov (United States)

    Saxena, Indu Fiesler; Hui, Kaleo; Astrahan, Melvin

    2010-09-01

    Measuring tissue temperature distribution during electromagnetically induced hyperthermia (HT) is challenging. High resistance thermistors with nonmetallic leads have been used successfully in commercial HT systems for about three decades. The single 1 mm thick temperature sensing element is mechanically moved to measure tissue temperature distributions. By employing a single thermometry probe containing a fixed linear sensor array temperature, distributions during therapy can be measured with greater ease. While the first attempts to use fiber Bragg grating (FBG) technology to obtain multiple temperature points along a single fiber have been reported, improvement in the detection system's stability were needed for clinical applications. The FBG temperature sensing system described here has a very high temporal stability detection system and an order of magnitude faster readout than commercial systems. It is shown to be suitable for multiple point fiber thermometry during microwave hyperthermia when compared to conventional mechanically scanning probe HT thermometry. A polymer coated fiber Bragg grating (PFBG) technology is described that provides a number of FBG thermometry locations along the length of a single optical fiber. The PFBG probe developed is tested under simulated microwave hyperthermia treatment to a tissue equivalent phantom. Two temperature probes, the multiple PFBG sensor and the Bowman probe, placed symmetrically with respect to a microwave antenna in a tissue phantom are subjected to microwave hyperthermia. Measurements are made at start of HT and 85 min later, when a 6 degrees C increase in temperature is registered by both probes, as is typical in clinical HT therapy. The optical fiber multipoint thermometry probe performs highly stable, real-time thermometry updating each multipoint thermometry scan over a 5 cm length every 2 s. Bowman probe measurements are acquired simultaneously for comparison. In addition, the PFBG sensor's detection

  9. Microwave-driven plasma gasification for biomass waste treatment at miniature scale

    NARCIS (Netherlands)

    Sturm, G.S.J.; Navarrete Muñoz, A.; Purushothaman Vellayani, A.; Stefanidis, G.

    2016-01-01

    Gasification technology may combine waste treatment with energy generation. Conventional gasification processes are bulky and inflexible. By using an external energy source, in the form of microwave-generated plasma, equipment size may be reduced and flexibility as regards to the feed composition

  10. Pd(OAc)2/DPPF-catalysed microwave-assisted cyanides-free ...

    Indian Academy of Sciences (India)

    Pd(OAc)2/DPPF-catalysed microwave-assisted cyanides-free synthesis of aryl nitriles. DINESH N. SAWANT and BHALCHANDRA M. BHANAGE*. Department of Chemistry, Institute of Chemical Technology, N. Parekh Marg, Matunga,. Mumbai 400019 India. e-mail bm.bhanage@ictmumbai.edu.in. INDEX ...

  11. Microwave and plasma-assisted modification of composite fiber surface topography

    Science.gov (United States)

    Paulauskas, Felix L [Knoxville, TN; White, Terry L [Knoxville, TN; Bigelow, Timothy S [Knoxville, TN

    2003-02-04

    The present invention introduces a novel method for producing an undulated surface on composite fibers using plasma technology and microwave radiation. The undulated surface improves the mechanical interlocking of the fibers to composite resins and enhances the mechanical strength and interfacial sheer strength of the composites in which they are introduced.

  12. Micromachined Microwave Cavity Resonator Filters for 5G: a Feasibility Study

    NARCIS (Netherlands)

    Kemenade, van R.; Smolders, A.B.; Hon, de B.P.

    2015-01-01

    Micromachined microwave cavity filters offer a light-weight, high-Q and highly integrated alternative in the frequency range of 20 GHz–100 GHz as compared to conventional filter types. The filter technology shows potential for use in 5G portable devices and as such, the design of a duplexer

  13. Laboratory microwave measurement of the moisture content in seed cotton and ginned cotton fiber

    Science.gov (United States)

    The timely and accurate measurement of cotton fiber moisture content is important, but the measurement is often performed by laborious, time-consuming laboratory oven drying methods. Microwave technology for measuring fiber moisture content directly (not for drying only) offers potential advantages...

  14. Applications of high power microwaves to atmospheric modification and measurement

    International Nuclear Information System (INIS)

    Benford, J.

    1993-01-01

    The current state of proposals to use high power microwaves in the atmosphere is reviewed. HPM has been proposed to aid in the conservation of stratospheric ozone by partial breakdown, facilitating chemistry to eliminate chlorine. Another proposal is over-the-horizon radar using a partial breakdown area in the ionosphere. A key to any such effort is rapid diagnosis of the state of the atmosphere before, during and after intervention. Technology requirements of these modification and measurement proposals are reviewed. The elements of an atmospheric modification program are identified and political, economic and ideological factors are discussed

  15. Design of a Microwave Duplexer without Ferrite and without Magnet

    Directory of Open Access Journals (Sweden)

    F. Mejri

    2018-06-01

    Full Text Available In this paper we present the design, realization and characterization of a microwave duplexer, compact, easy to realize and integrate into systems such as ground penetrating radars. It is made without the use of ferrite or magnet. This device is designed in the S band and made in micro-ribbon technology. It consists of a power divider and two RF amplifiers, low gain, using a BFR91 bipolar transistor. The latter is frequently available and inexpensive. Measurements made on a vector network analyzer have shown a low insertion loss with insulation considered satisfactory – for low power applications - between the transmitter (Tx and the receiver (Rx circuits.

  16. [Cosmic Microwave Background (CMB) Anisotropies

    Science.gov (United States)

    Silk, Joseph

    1998-01-01

    One of the main areas of research is the theory of cosmic microwave background (CMB) anisotropies and analysis of CMB data. Using the four year COBE data we were able to improve existing constraints on global shear and vorticity. We found that, in the flat case (which allows for greatest anisotropy), (omega/H)0 less than 10(exp -7), where omega is the vorticity and H is the Hubble constant. This is two orders of magnitude lower than the tightest, previous constraint. We have defined a new set of statistics which quantify the amount of non-Gaussianity in small field cosmic microwave background maps. By looking at the distribution of power around rings in Fourier space, and at the correlations between adjacent rings, one can identify non-Gaussian features which are masked by large scale Gaussian fluctuations. This may be particularly useful for identifying unresolved localized sources and line-like discontinuities. Levin and collaborators devised a method to determine the global geometry of the universe through observations of patterns in the hot and cold spots of the CMB. We have derived properties of the peaks (maxima) of the CMB anisotropies expected in flat and open CDM models. We represent results for angular resolutions ranging from 5 arcmin to 20 arcmin (antenna FWHM), scales that are relevant for the MAP and COBRA/SAMBA space missions and the ground-based interferometer. Results related to galaxy formation and evolution are also discussed.

  17. Probing Inflation via Cosmic Microwave Background Polarimetry

    Science.gov (United States)

    Chuss, David T.

    2008-01-01

    The Cosmic Microwave Background (CMB) has been a rich source of information about the early Universe. Detailed measurements of its spectrum and spatial distribution have helped solidify the Standard Model of Cosmology. However, many questions still remain. Standard Cosmology does not explain why the early Universe is geometrically flat, expanding, homogenous across the horizon, and riddled with a small anisotropy that provides the seed for structure formation. Inflation has been proposed as a mechanism that naturally solves these problems. In addition to solving these problems, inflation is expected to produce a spectrum of gravitational waves that will create a particular polarization pattern on the CMB. Detection of this polarized signal is a key test of inflation and will give a direct measurement of the energy scale at which inflation takes place. This polarized signature of inflation is expected to be -9 orders of magnitude below the 2.7 K monopole level of the CMB. This measurement will require good control of systematic errors, an array of many detectors having the requisite sensitivity, and a reliable method for removing polarized foregrounds, and nearly complete sky coverage. Ultimately, this measurement is likely to require a space mission. To this effect, technology and mission concept development are currently underway.

  18. Microwave radiation (2.45 GHz)-induced oxidative stress: Whole-body exposure effect on histopathology of Wistar rats.

    Science.gov (United States)

    Chauhan, Parul; Verma, H N; Sisodia, Rashmi; Kesari, Kavindra Kumar

    2017-01-01

    Man-made microwave and radiofrequency (RF) radiation technologies have been steadily increasing with the growing demand of electronic appliances such as microwave oven and cell phones. These appliances affect biological systems by increasing free radicals, thus leading to oxidative damage. The aim of this study was to explore the effect of 2.45 GHz microwave radiation on histology and the level of lipid peroxide (LPO) in Wistar rats. Sixty-day-old male Wistar rats with 180 ± 10 g body weight were used for this study. Animals were divided into two groups: sham exposed (control) and microwave exposed. These animals were exposed for 2 h a day for 35 d to 2.45 GHz microwave radiation (power density, 0.2 mW/cm 2 ). The whole-body specific absorption rate (SAR) was estimated to be 0.14 W/kg. After completion of the exposure period, rats were sacrificed, and brain, liver, kidney, testis and spleen were stored/preserved for determination of LPO and histological parameters. Significantly high level of LPO was observed in the liver (p body microwave exposure, compared to the control group. Based on the results obtained in this study, we conclude that exposure to microwave radiation 2 h a day for 35 d can potentially cause histopathology and oxidative changes in Wistar rats. These results indicate possible implications of such exposure on human health.

  19. Two-step fast microwave-assisted pyrolysis of biomass for bio-oil production using microwave absorbent and HZSM-5 catalyst.

    Science.gov (United States)

    Zhang, Bo; Zhong, Zhaoping; Xie, Qinglong; Liu, Shiyu; Ruan, Roger

    2016-07-01

    A novel technology of two-step fast microwave-assisted pyrolysis (fMAP) of corn stover for bio-oil production was investigated in the presence of microwave absorbent (SiC) and HZSM-5 catalyst. Effects of fMAP temperature and catalyst-to-biomass ratio on bio-oil yield and chemical components were examined. The results showed that this technology, employing microwave, microwave absorbent and HZSM-5 catalyst, was effective and promising for biomass fast pyrolysis. The fMAP temperature of 500°C was considered the optimum condition for maximum yield and best quality of bio-oil. Besides, the bio-oil yield decreased linearly and the chemical components in bio-oil were improved sequentially with the increase of catalyst-to-biomass ratio from 1:100 to 1:20. The elemental compositions of bio-char were also determined. Additionally, compared to one-step fMAP process, two-step fMAP could promote the bio-oil quality with a smaller catalyst-to-biomass ratio. Copyright © 2016. Published by Elsevier B.V.

  20. Using microwave Doppler radar in automated manufacturing applications

    Science.gov (United States)

    Smith, Gregory C.

    Since the beginning of the Industrial Revolution, manufacturers worldwide have used automation to improve productivity, gain market share, and meet growing or changing consumer demand for manufactured products. To stimulate further industrial productivity, manufacturers need more advanced automation technologies: "smart" part handling systems, automated assembly machines, CNC machine tools, and industrial robots that use new sensor technologies, advanced control systems, and intelligent decision-making algorithms to "see," "hear," "feel," and "think" at the levels needed to handle complex manufacturing tasks without human intervention. The investigator's dissertation offers three methods that could help make "smart" CNC machine tools and industrial robots possible: (1) A method for detecting acoustic emission using a microwave Doppler radar detector, (2) A method for detecting tool wear on a CNC lathe using a Doppler radar detector, and (3) An online non-contact method for detecting industrial robot position errors using a microwave Doppler radar motion detector. The dissertation studies indicate that microwave Doppler radar could be quite useful in automated manufacturing applications. In particular, the methods developed may help solve two difficult problems that hinder further progress in automating manufacturing processes: (1) Automating metal-cutting operations on CNC machine tools by providing a reliable non-contact method for detecting tool wear, and (2) Fully automating robotic manufacturing tasks by providing a reliable low-cost non-contact method for detecting on-line position errors. In addition, the studies offer a general non-contact method for detecting acoustic emission that may be useful in many other manufacturing and non-manufacturing areas, as well (e.g., monitoring and nondestructively testing structures, materials, manufacturing processes, and devices). By advancing the state of the art in manufacturing automation, the studies may help

  1. Enhanced Harnessing of the Graviola Bioactive Components Using a Neoteric Sonication Cum Microwave Coadjuvant Extraction Protocol

    Directory of Open Access Journals (Sweden)

    Se Chul Chun

    2018-02-01

    Full Text Available Graviola is one of the most accomplished natural anticancer therapists gaining popularity in recent times. Harnessing the full benefit from tapping all of its rich bioactive reservoirs is absolutely worthy and mandatory. It is in this regard that a well optimized extraction methodology gains paramount importance. In case of Graviola, no sophistication in terms of extraction methods is reported. A neoteric sonication cum microwave combined extraction technology was introduced that maximized the extraction process and minimized (7 min the extraction time. The extraction efficiency was validated based on the significant enrichment of bioactive ingredients in Graviola extracts following the sonication cum microwave combined protocol.

  2. Application of microwave ablation in treatment of solid space-occupying lesions in the liver

    Directory of Open Access Journals (Sweden)

    DU Lei

    2017-10-01

    Full Text Available With the development of science and technology, many therapies for hepatic space-occupying lesions have emerged, such as surgical operation, chemotherapy, intervention, and biological therapy. In recent years, microwave technique for the treatment of hepatic space-occupying lesions has attracted more and more attention because of its small trauma, low expense, marked clinical effect, and few complications. This article reviews the advances in the application of microwave in the treatment of liver cancer, hepatic hemangioma, hepatic alveolar echinococcosis, and other benign hepatic space-occupying lesions.

  3. Phase noise in RF and microwave amplifiers.

    Science.gov (United States)

    Boudot, Rodolphe; Rubiola, Enrico

    2012-12-01

    Understanding amplifier phase noise is a critical issue in many fields of engineering and physics, such as oscillators, frequency synthesis, telecommunication, radar, and spectroscopy; in the emerging domain of microwave photonics; and in exotic fields, such as radio astronomy, particle accelerators, etc. Focusing on the two main types of base noise in amplifiers, white and flicker, the power spectral density of the random phase φ(t) is Sφ(f) = b(0) + b(-1)/f. White phase noise results from adding white noise to the RF spectrum in the carrier region. For a given RF noise level, b(0) is proportional to the reciprocal of the carrier power P(0). By contrast, flicker results from a near-dc 1/f noise-present in all electronic devices-which modulates the carrier through some parametric effect in the semiconductor. Thus, b(-1) is a parameter of the amplifier, constant in a wide range of P(0). The consequences are the following: Connecting m equal amplifiers in parallel, b(-1) is 1/m times that of one device. Cascading m equal amplifiers, b(-1) is m times that of one amplifier. Recirculating the signal in an amplifier so that the gain increases by a power of m (a factor of m in decibels) as a result of positive feedback (regeneration), we find that b(-1) is m(2) times that of the amplifier alone. The feedforward amplifier exhibits extremely low b(-1) because the carrier is ideally nulled at the input of its internal error amplifier. Starting with an extensive review of the literature, this article introduces a system-oriented model which describes the phase flickering. Several amplifier architectures (cascaded, parallel, etc.) are analyzed systematically, deriving the phase noise from the general model. There follow numerous measurements of amplifiers using different technologies, including some old samples, and in a wide frequency range (HF to microwaves), which validate the theory. In turn, theory and results provide design guidelines and give suggestions for CAD and

  4. Continuous microwave flow synthesis of mesoporous hydroxyapatite.

    Science.gov (United States)

    Akram, Muhammad; Alshemary, Ammar Z; Goh, Yi-Fan; Wan Ibrahim, Wan Aini; Lintang, Hendrik O; Hussain, Rafaqat

    2015-11-01

    We have successfully used continuous microwave flow synthesis (CMFS) technique for the template free synthesis of mesoporous hydroxyapatite. The continuous microwave flow reactor consisted of a modified 2.45GHz household microwave, peristaltic pumps and a Teflon coil. This cost effective and efficient system was exploited to produce semi-crystalline phase pure nano-sized hydroxyapatite. Effect of microwave power, retention time and the concentration of reactants on the phase purity, degree of crystallinity and surface area of the final product was studied in detail. X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) were used to study the phase purity and composition of the product, while transmission electron microscopy (TEM) was used to study the effect of process parameters on the morphology of hydroxyapatite. The TEM analysis confirmed the formation of spherical particles at low microwave power; however the morphology of the particles changed to mesoporous needle and rod-like structure upon exposing the reaction mixture to higher microwave power and longer retention time inside the microwave. The in-vitro ion dissolution behavior of the as synthesized hydroxyapatite was studied by determining the amount of Ca(2+) ion released in SBF solution. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Microfabricated Microwave-Integrated Surface Ion Trap

    Science.gov (United States)

    Revelle, Melissa C.; Blain, Matthew G.; Haltli, Raymond A.; Hollowell, Andrew E.; Nordquist, Christopher D.; Maunz, Peter

    2017-04-01

    Quantum information processing holds the key to solving computational problems that are intractable with classical computers. Trapped ions are a physical realization of a quantum information system in which qubits are encoded in hyperfine energy states. Coupling the qubit states to ion motion, as needed for two-qubit gates, is typically accomplished using Raman laser beams. Alternatively, this coupling can be achieved with strong microwave gradient fields. While microwave radiation is easier to control than a laser, it is challenging to precisely engineer the radiated microwave field. Taking advantage of Sandia's microfabrication techniques, we created a surface ion trap with integrated microwave electrodes with sub-wavelength dimensions. This multi-layered device permits co-location of the microwave antennae and the ion trap electrodes to create localized microwave gradient fields and necessary trapping fields. Here, we characterize the trap design and present simulated microwave performance with progress towards experimental results. This research was funded, in part, by the Office of the Director of National Intelligence (ODNI), Intelligence Advanced Research Projects Activity (IARPA).

  6. Microwave based method of monitoring crack formation

    International Nuclear Information System (INIS)

    Aman, Sergej; Aman, Alexander; Majcherek, Soeren; Hirsch, Soeren; Schmidt, Bertram

    2014-01-01

    The formation of cracks in glass particles was monitored by application of linearly polarized microwaves. The breakage behavior of glass spheres coated with a thin gold layer of about 50 nm, i.e. a thickness that is lower than the microwave penetration depth, was tested. In this way the investigation of fracture behavior of electronic circuits was simulated. A shielding current was induced in the gold layer by the application of microwaves. During the crack formation the distribution of this current changed abruptly and a scattered microwave signal appeared at the frequency of the incident microwaves. The time behavior of the scattered signal reflects the microscopic processes occurring during the fracture of the specimen. The duration of the increasing signal corresponds to the crack formation time in the tested specimen. This time was estimated as particle size divided by crack development speed in glass. An intense emission of electrons occurs during the formation of cracks. Due to this, coherent Thomson scattering of microwaves by emitted electrons becomes significant with a delay of a few microseconds after the initial phase of crack formation. In this time the intensity of the microwave signal increases. (paper)

  7. Microwave combustion and sintering without isostatic pressure

    International Nuclear Information System (INIS)

    Ebadian, M.A.

    1998-01-01

    In recent years interest has grown rapidly in the application of microwave energy to the processing of ceramics, composites, polymers, and other materials. Advances in the understanding of microwave/materials interactions will facilitate the production of new ceramic materials with superior mechanical properties. One application of particular interest is the use of microwave energy for the mobilization of uranium for subsequent redeposition. Phase III (FY98) will focus on the microwave assisted chemical vapor infiltration tests for mobilization and redeposition of radioactive species in the mixed sludge waste. Uranium hexachloride and uranium (IV) borohydride are volatile compounds for which the chemical vapor infiltration procedure might be developed for the separation of uranium. Microwave heating characterized by an inverse temperature profile within a preformed ceramic matrix will be utilized for CVI using a carrier gas. Matrix deposition is expected to commence from the inside of the sample where the highest temperature is present. The preform matrix materials, which include aluminosilicate based ceramics and silicon carbide based ceramics, are all amenable to extreme volume reduction, densification, and vitrification. Important parameters of microwave sintering such as frequency, power requirement, soaking temperature, and holding time will be investigated to optimize process conditions for the volatilization of uranyl species using a reactive carrier gas in a microwave chamber

  8. Medical preparation container comprising microwave powered sensor assembly

    DEFF Research Database (Denmark)

    2016-01-01

    The present invention relates to a medical preparation container which comprises a microwave powered sensor assembly. The microwave powered sensor assembly comprises a sensor configured to measure a physical property or chemical property of a medical preparation during its heating in a microwave ...... oven. The microwave powered sensor assembly is configured for harvesting energy from microwave radiation emitted by the microwave oven and energize the sensor by the harvested microwave energy.......The present invention relates to a medical preparation container which comprises a microwave powered sensor assembly. The microwave powered sensor assembly comprises a sensor configured to measure a physical property or chemical property of a medical preparation during its heating in a microwave...

  9. Measuring tropospheric wind with microwave sounders

    Science.gov (United States)

    Lambrigtsen, B.; Su, H.; Turk, J.; Hristova-Veleva, S. M.; Dang, V. T.

    2017-12-01

    In its 2007 "Decadal Survey" of earth science missions for NASA the U.S. National Research Council recommended that a Doppler wind lidar be developed for a three-dimensional tropospheric winds mission ("3D-Winds"). The technology required for such a mission has not yet been developed, and it is expected that the next Decadal Survey, planned to be released by the end of 2017, will put additional emphasis on the still pressing need for wind measurements from space. The first Decadal Survey also called for a geostationary microwave sounder (GMS) on a Precipitation and All-weather Temperature and Humidity (PATH) mission, which could be used to measure wind from space. Such a sounder, the Geostationary Synthetic Thinned Aperture Radiometer (GeoSTAR), has been developed at the Jet Propulsion Laboratory (JPL). The PATH mission has not yet been funded by NASA, but a low-cost subset of PATH, GeoStorm has been proposed as a hosted payload on a commercial communications satellite. Both PATH and GeoStorm would obtain frequent (every 15 minutes of better) measurements of tropospheric water vapor profiles, and they can be used to derive atmospheric motion vector (AMV) wind profiles, even in the presence of clouds. Measurement of wind is particularly important in the tropics, where the atmosphere is largely not in thermal balance and wind estimates cannot generally be derived from temperature and pressure fields. We report on simulation studies of AMV wind vectors derived from a GMS and from a cluster of low-earth-orbiting (LEO) small satellites (e.g., CubeSats). The results of two separate simulation studies are very encouraging and show that a ±2 m/s wind speed precision is attainable, which would satisfy WMO requirements. A GMS observing system in particular, which can be implemented now, would enable significant progress in the study of atmospheric dynamics. Copyright 2017 California Institute of Technology. Government sponsorship acknowledged

  10. Bone-like hydroxyapatite precipitated from 10×SBF-like solution by microwave irradiation

    International Nuclear Information System (INIS)

    Tolga Demirtaş, T.; Kaynak, Gökçe; Gümüşderelioğlu, Menemşe

    2015-01-01

    Microwave-assisted methods have been frequently used in many processes owing to their numerous advantages such as performing fast, efficient and homogenous processes and reducing side reactions. In view of these benefits, in this study it was purposed to produce bone-like hydroxyapatite (HA) by inducing biomimetic process with microwave-irradiation. This is why, concentrated body fluid (SBF) i.e. 10×SBF-like solution was used and it was precipitated in different microwave powers i.e. 90 W, 360 W, 600 W, and 1200 W and in different exposure times. For comparison, precipitation process was also carried out at room temperature for 6 h and at 80 °C for 1 h. The obtained HA structures were characterized by appropriate instrumental techniques. As a result, microwave-induced precipitation at 600 W for 9 times 30 s was determined as the optimum condition for the production of HA which has similar properties to the cortical bone. At this condition, B-type HA with 9.22% (wt.) carbonate content, 1.61 Ca/P molar ratio and amorphous structure was obtained easily, rapidly and efficiently. So, this is the first time microwave technology has been used to precipitate HA from SBF solution. - Highlights: • Simple, rapid and efficient method was developed to produce bone-like HA. • Microwave radiation and biomimetic approach via 10×SBF-like solution were combined. • Microwave irradiation at 600 W for 9 × 30 s was determined as the optimum condition. • B-type HA (carbonate content: 9.22%; 1.61 Ca/P:1.61; amorph) was produced. • This method may be employed for the effective HA coating of 3D bone scaffolds

  11. Bone-like hydroxyapatite precipitated from 10×SBF-like solution by microwave irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Tolga Demirtaş, T.; Kaynak, Gökçe [Bioengineering Engineering Department, Hacettepe University, 06800 Beytepe, Ankara (Turkey); Gümüşderelioğlu, Menemşe, E-mail: menemse@hacettepe.edu.tr [Bioengineering Engineering Department, Hacettepe University, 06800 Beytepe, Ankara (Turkey); Chemical Engineering Department, Hacettepe University, 06800 Beytepe, Ankara (Turkey)

    2015-04-01

    Microwave-assisted methods have been frequently used in many processes owing to their numerous advantages such as performing fast, efficient and homogenous processes and reducing side reactions. In view of these benefits, in this study it was purposed to produce bone-like hydroxyapatite (HA) by inducing biomimetic process with microwave-irradiation. This is why, concentrated body fluid (SBF) i.e. 10×SBF-like solution was used and it was precipitated in different microwave powers i.e. 90 W, 360 W, 600 W, and 1200 W and in different exposure times. For comparison, precipitation process was also carried out at room temperature for 6 h and at 80 °C for 1 h. The obtained HA structures were characterized by appropriate instrumental techniques. As a result, microwave-induced precipitation at 600 W for 9 times 30 s was determined as the optimum condition for the production of HA which has similar properties to the cortical bone. At this condition, B-type HA with 9.22% (wt.) carbonate content, 1.61 Ca/P molar ratio and amorphous structure was obtained easily, rapidly and efficiently. So, this is the first time microwave technology has been used to precipitate HA from SBF solution. - Highlights: • Simple, rapid and efficient method was developed to produce bone-like HA. • Microwave radiation and biomimetic approach via 10×SBF-like solution were combined. • Microwave irradiation at 600 W for 9 × 30 s was determined as the optimum condition. • B-type HA (carbonate content: 9.22%; 1.61 Ca/P:1.61; amorph) was produced. • This method may be employed for the effective HA coating of 3D bone scaffolds.

  12. Microwave line of sight link engineering

    CERN Document Server

    Angueira, Pablo

    2012-01-01

    A comprehensive guide to the design, implementation, and operation of line of sight microwave link systems The microwave Line of Sight (LOS) transport network of any cellular operator requires at least as much planning effort as the cellular infrastructure itself. The knowledge behind this design has been kept private by most companies and has not been easy to find. Microwave Line of Sight Link Engineering solves this dilemma. It provides the latest revisions to ITU reports and recommendations, which are not only key to successful design but have changed dramatically in

  13. Microwave Enhanced Cotunneling in SET Transistors

    DEFF Research Database (Denmark)

    Manscher, Martin; Savolainen, M.; Mygind, Jesper

    2003-01-01

    Cotunneling in single electron tunneling (SET) devices is an error process which may severely limit their electronic and metrologic applications. Here is presented an experimental investigation of the theory for adiabatic enhancement of cotunneling by coherent microwaves. Cotunneling in SET...... transistors has been measured as function of temperature, gate voltage, frequency, and applied microwave power. At low temperatures and applied power levels, including also sequential tunneling, the results can be made consistent with theory using the unknown damping in the microwave line as the only free...

  14. Aspects of microwave-heating uniformity

    International Nuclear Information System (INIS)

    Ginsberg, T.; Makowitz, H.

    1983-01-01

    Interest has been shown in the field of nuclear reactor safety in the use of microwave heating to simulate the nuclear heat source. The objective of the investigation reported here was to evaluate the usefulness of microwave dielectric heating as a simulator of the nuclear heat source in experiments which simulate the process of boiling of molten mixtures of nuclear fuel and steel. This paper summarizes the results of studies of several aspects of energy deposition in dielectric liquid samples which are exposed to microwave radiation

  15. RF and microwave coupled-line circuits

    CERN Document Server

    Mongia, R K; Bhartia, P; Hong, J; Gupta, K C

    2007-01-01

    This extensively revised edition of the 1999 Artech House classic, RF and Microwave Coupled-Line Circuits, offers you a thoroughly up-to-date understanding of coupled line fundamentals, explaining their applications in designing microwave and millimeter-wave components used in today's communications, microwave, and radar systems. The Second Edition includes a wealth of new material, particularly relating to applications. You find brand new discussions on a novel simple design technique for multilayer coupled circuits, high pass filters using coupled lines, software packages used for filter des

  16. Optimization of microwave heating in an existing cubicle cavity by incorporating additional wave guide and control components

    International Nuclear Information System (INIS)

    Erle, R.R.; Eschen, V.G.; Sprenger, G.S.

    1995-04-01

    The use of microwave energy to thermally treat Low Level (LLW), Transuranic (TRU), and mixed waste has been under development at the Rocky Flats Environmental Technology Site (Site) since 1986. During that time, the technology has progressed from bench-scale tests, through pilot-scale tests, and finally to a full-scale demonstration unit. Experimental operations have been conducted on a variety of non-radioactive surrogates and actual radioactive waste forms. Through these studies and development efforts, the Microwave Vitrification Engineering Team (MVET) at Rocky Flats has successfully proven the application of microwave energy for waste treatment operations. In the microwave solidification process, microwave energy is used to heat a mixture of waste and glass frit to produce a vitrified product that meets all the current acceptance criteria at the final disposal sites. All of the development to date has utilized a multi-mode microwave system to provide the energy to treat the materials. Currently, evaluations are underway on modifications to the full-scale demonstration system that provide a single-mode operation as a possible method to optimize the system. This poster presentation describes the modifications made to allow the single-mode operation

  17. Microwave Excitation In ECRIS plasmas

    International Nuclear Information System (INIS)

    Ciavola, G.; Celona, L.; Consoli, F.; Gammino, S.; Maimone, F.; Barbarino, S.; Catalano, R. S.; Mascali, D.; Tumino, L.

    2007-01-01

    A number of phenomena related to the electron cyclotron resonance ion sources (ECRIS) has been better understood recently by means of the improvement of comprehension of the coupling mechanism between microwave generators and ECR plasma. In particular, the two frequency heating and the frequency tuning effect, that permit a remarkable increase of the current for the highest charge states ions, can be explained in terms of modes excitation in the cylindrical cavity of the plasma chamber. Calculations based on this theoretical approach have been performed, and the major results will be presented. It will be shown that the electric field pattern completely changes for a few MHz frequency variations and the changes in ECRIS performances can be correlated to the efficiency of the power transfer between electromagnetic field and plasma

  18. Polarization of Cosmic Microwave Background

    International Nuclear Information System (INIS)

    Buzzelli, A; Cabella, P; De Gasperis, G; Vittorio, N

    2016-01-01

    In this work we present an extension of the ROMA map-making code for data analysis of Cosmic Microwave Background polarization, with particular attention given to the inflationary polarization B-modes. The new algorithm takes into account a possible cross- correlated noise component among the different detectors of a CMB experiment. We tested the code on the observational data of the BOOMERanG (2003) experiment and we show that we are provided with a better estimate of the power spectra, in particular the error bars of the BB spectrum are smaller up to 20% for low multipoles. We point out the general validity of the new method. A possible future application is the LSPE balloon experiment, devoted to the observation of polarization at large angular scales. (paper)

  19. Microwave Imaging Reflectometer for TEXTOR

    International Nuclear Information System (INIS)

    T. Munsat; E. Mazzucato; H. Park; B.H. Deng; C.W. Domier; N.C. Luhmann, Jr.; J. Wang; Z.G. Xia; A.J.H. Donne; and M. van de Pol

    2002-01-01

    Understanding the behavior of fluctuations in magnetically confined plasmas is essential to the advancement of turbulence-based transport physics. Though microwave reflectometry has proven to be an extremely useful and sensitive tool for measuring small density fluctuations in some circumstances, this technique has been shown to have limited viability for large amplitude, high kq fluctuations and/or core measurements. To this end, a new instrument based on 2-D imaging reflectometry has been developed to measure density fluctuations over an extended plasma region in the TEXTOR tokamak. This technique is made possible by collecting an extended spectrum of reflected waves with large-aperture imaging optics. Details of the imaging reflectometry concept, as well as technical details of the TEXTOR instrument will be presented. Data from roof-of-principle experiments on TEXTOR using a prototype system is presented, as well as results from a systematic off-line study of the advantages and limitations of the imaging reflectometer

  20. Microwave Impedance Measurement for Nanoelectronics

    Directory of Open Access Journals (Sweden)

    M. Randus

    2011-04-01

    Full Text Available The rapid progress in nanoelectronics showed an urgent need for microwave measurement of impedances extremely different from the 50Ω reference impedance of measurement instruments. In commonly used methods input impedance or admittance of a device under test (DUT is derived from measured value of its reflection coefficient causing serious accuracy problems for very high and very low impedances due to insufficient sensitivity of the reflection coefficient to impedance of the DUT. This paper brings theoretical description and experimental verification of a method developed especially for measurement of extreme impedances. The method can significantly improve measurement sensitivity and reduce errors caused by the VNA. It is based on subtraction (or addition of a reference reflection coefficient and the reflection coefficient of the DUT by a passive network, amplifying the resulting signal by an amplifier and measuring the amplified signal as a transmission coefficient by a common vector network analyzer (VNA. A suitable calibration technique is also presented.

  1. Microwave discharges in capillary tubes

    International Nuclear Information System (INIS)

    Dervisevic, Emil

    1984-01-01

    This research thesis aims at being a contribution to the study of microwave discharge by a surface wave, and more precisely focusses on the discharge in capillary tubes filled with argon. The author first present theoretical models which describe, on the one hand, the propagation of the surface wave along the plasma column, and, on the other hand, longitudinal and radial profiles of the main discharge characteristics. The second part addresses the study of the influence of parameters (gas pressure and tube radius) on discharge operation and characteristics. Laws of similitude as well as empirical relationships between argon I and argon II emission line intensities, electron density, and electric field in the plasma have been established [fr

  2. Reflection measurements of microwave absorbers

    Science.gov (United States)

    Baker, Dirk E.; van der Neut, Cornelis A.

    1988-12-01

    A swept-frequency interferometer is described for making rapid, real-time assessments of localized inhomogeneities in planar microwave absorber panels. An aperture-matched exponential horn is used to reduce residual reflections in the system to about -37 dB. This residual reflection is adequate for making comparative measurements on planar absorber panels whose reflectivities usually fall in the -15 to -25 dB range. Reflectivity measurements on a variety of planar absorber panels show that multilayer Jaumann absorbers have the greatest inhomogeneity, while honeycomb absorbers generally have excellent homogeneity within a sheet and from sheet to sheet. The test setup is also used to measure the center frequencies of resonant absorbers. With directional couplers and aperture-matched exponential horns, the technique can be easily applied in the standard 2 to 40 GHz waveguide bands.

  3. A low-cost, modular, microwave-linked, color TV inspection system

    International Nuclear Information System (INIS)

    Panda, N.C.

    1991-01-01

    This paper reports that many custom-built radiation-shielded CCTV inspection systems for nuclear facilities are available in the market. This author, however, could find no reference to units using low-cost nodular technology for wireless transmission and control of color CCTV signals in radiation environments. The system that was developed is a process control observation tool geared toward identifying locations ad volumes of accumulated in-cell solids. It also performs remote integrity assessments of tanks and pipe routings that are required by regulatory agencies. System highlights are: microwave transmission of video and control signals, low cost, low maintenance, and modular design. Use of standard components enables easy exchange of modules. Microwave transmission resolved the complications of a wired system while increasing reliability and safety. The video image is created by the remote in-cell color TV camera and transmitted by microwave out of the cell to TV monitors at consoles in non-radiation zones

  4. Heat transfer enhanced microwave process for stabilization of liquid radioactive waste slurry. Final report

    International Nuclear Information System (INIS)

    White, T.L.

    1995-01-01

    The objectve of this CRADA is to combine a polymer process for encapsulation of liquid radioactive waste slurry developed by Monolith Technology, Inc. (MTI), with an in-drum microwave process for drying radioactive wastes developed by Oak Ridge National Laboratory (ORNL), for the purpose of achieving a fast, cost-effectve commercial process for solidification of liquid radioactive waste slurry. Tests performed so far show a four-fold increase in process throughput due to the direct microwave heating of the polymer/slurry mixture, compared to conventional edge-heating of the mixer. We measured a steady-state throughput of 33 ml/min for 1.4 kW of absorbed microwave power. The final waste form is a solid monolith with no free liquids and no free particulates

  5. Control of plasma profile in microwave discharges via inverse-problem approach

    Directory of Open Access Journals (Sweden)

    Yasuyoshi Yasaka

    2013-12-01

    Full Text Available In the manufacturing process of semiconductors, plasma processing is an essential technology, and the plasma used in the process is required to be of high density, low temperature, large diameter, and high uniformity. This research focuses on the microwave-excited plasma that meets these needs, and the research target is a spatial profile control. Two novel techniques are introduced to control the uniformity; one is a segmented slot antenna that can change radial distribution of the radiated field during operation, and the other is a hyper simulator that can predict microwave power distribution necessary for a desired radial density profile. The control system including these techniques provides a method of controlling radial profiles of the microwave plasma via inverse-problem approach, and is investigated numerically and experimentally.

  6. Broadband microwave frequency doubler based on left-handed nonlinear transmission lines

    International Nuclear Information System (INIS)

    Huang Jie; Gu Wenwen; Zhao Qian

    2017-01-01

    A bandwidth microwave second harmonic generator is successfully designed using composite right/left-handed nonlinear transmission lines (CRLH NLTLs) in a GaAs monolithic microwave integrated circuit (MMIC) technology. The structure parameters of CRLH NLTLs, e.g. host transmission line, rectangular spiral inductor, and nonlinear capacitor, have a great impact on the second harmonic performance enhancement in terms of second harmonic frequency, output power, and conversion efficiency. It has been experimentally demonstrated that the second harmonic frequency is determined by the anomalous dispersion of CRLH NLTLs and can be significantly improved by effectively adjusting these structure parameters. A good agreement between the measured and simulated second harmonic performances of Ka-band CRLH NLTLs frequency multipliers is successfully achieved, which further validates the design approach of frequency multipliers on CRLH NLTLs and indicates the potentials of CRLH NLTLs in terms of the generation of microwave and millimeter-wave signal source. (paper)

  7. Impact of aerosol particles on the structure of an atmospheric pressure microwave plasma afterglow

    Energy Technology Data Exchange (ETDEWEB)

    Chen Chunku [Ceramic and Composite Materials Centre, 209 Farris Engineering Centre, University of New Mexico, Albuquerque, NM (United States); Phillips, Jonathan [Los Alamos National Laboratory, MS C930, Los Alamos, NM (United States)

    2002-05-21

    Several novel ceramic processing technologies (e.g. oxide ceramic melting and spheroidization) using an atmospheric pressure microwave plasma torch were recently developed in our lab. Understanding the processes and optimization requires complete characterization of the plasma as a function of operating condition. As a first step, a non-intrusive spectroscopic method was employed to map rotational (gas), electron and excitation temperatures and electron densities of the afterglow region of microwave generated atmospheric plasmas with and without alumina particle aerosol. Two-dimensional spatially resolved mapping of rotational (gas), excitation and electron temperatures and electron densities as a function of operating conditions during material processing were developed. It was shown that the passage of an aerosol dramatically changes the structure of the afterglow. Also the non-equilibrium nature of microwave generated atmospheric argon plasma was confirmed, suggesting that only multi-temperature models are capable of modelling this region of the plasma. (author)

  8. On-line measurement of the microwave power in ECR ion source

    International Nuclear Information System (INIS)

    Zhou Changgeng; Kang Wu; Hu Yonghong; Li Yan; Lou Benchao; Zu Xiulan; Xiong Riheng; Chen Junguang

    2005-01-01

    It is a new technology that ECR ion source is applied in the neutron generator. Because of effect of the structure, working state of ECR ion source could not be judged by the color of gas discharging in discharging chamber as doing in high frequency ion source. Therefore, state adjusting of ECR ion source was difficult in running of the neutron generator. The method to resolve the question is described in this paper. The micro-wave power was measured in case of running by using the method of directional coupler adding small microwave power meter. Because both were in the direct proportion, the ion beam current could be educed from microwave incidence power measured, and discharge state in discharge chamber could be judged. Finally, the neutron generator might be operated in best running state. (authors)

  9. Rheological, Chemical and Physical Characteristics of Golden Berry (Physalis peruviana L.) after Convective and Microwave Drying.

    Science.gov (United States)

    Nawirska-Olszańska, Agnieszka; Stępień, Bogdan; Biesiada, Anita; Kolniak-Ostek, Joanna; Oziembłowski, Maciej

    2017-07-29

    Studies on methods for fixing foods (with a slight loss of bioactive compounds) and obtaining attractive products are important with respect to current technology. The drying process allows for a product with highly bioactive properties. Drying of Physalis fruit was carried out in a conventional manner, and in a microwave under reduced pressure at 120 W and 480 W. After drying, the fruits were subjected to strength and rheological tests. Water activity, content of carotenoids and polyphenols and antioxidant activity as well as colour were also examined. The study showed that Physalis is a difficult material for drying. The best results were obtained using microwave drying at a power of 480 W. Physalis fruit microwave-dried by this method is characterized by higher resistance to compression than the fruit dried by convection. Dried fruit obtained in this way was characterized by higher contents of bioactive compounds, better antioxidant properties, and at the same time the lowest water activity.

  10. Rheological, Chemical and Physical Characteristics of Golden Berry (Physalis peruviana L. after Convective and Microwave Drying

    Directory of Open Access Journals (Sweden)

    Agnieszka Nawirska-Olszańska

    2017-07-01

    Full Text Available Studies on methods for fixing foods (with a slight loss of bioactive compounds and obtaining attractive products are important with respect to current technology. The drying process allows for a product with highly bioactive properties. Drying of Physalis fruit was carried out in a conventional manner, and in a microwave under reduced pressure at 120 W and 480 W. After drying, the fruits were subjected to strength and rheological tests. Water activity, content of carotenoids and polyphenols and antioxidant activity as well as colour were also examined. The study showed that Physalis is a difficult material for drying. The best results were obtained using microwave drying at a power of 480 W. Physalis fruit microwave-dried by this method is characterized by higher resistance to compression than the fruit dried by convection. Dried fruit obtained in this way was characterized by higher contents of bioactive compounds, better antioxidant properties, and at the same time the lowest water activity.

  11. AMISS - Active and passive MIcrowaves for Security and Subsurface imaging

    Science.gov (United States)

    Soldovieri, Francesco; Slob, Evert; Turk, Ahmet Serdar; Crocco, Lorenzo; Catapano, Ilaria; Di Matteo, Francesca

    2013-04-01

    The FP7-IRSES project AMISS - Active and passive MIcrowaves for Security and Subsurface imaging is based on a well-combined network among research institutions of EU, Associate and Third Countries (National Research Council of Italy - Italy, Technische Universiteit Delft - The Netherlands, Yildiz Technical University - Turkey, Bauman Moscow State Technical University - Russia, Usikov Institute for Radio-physics and Electronics and State Research Centre of Superconductive Radioelectronics "Iceberg" - Ukraine and University of Sao Paulo - Brazil) with the aims of achieving scientific advances in the framework of microwave and millimeter imaging systems and techniques for security and safety social issues. In particular, the involved partners are leaders in the scientific areas of passive and active imaging and are sharing their complementary knowledge to address two main research lines. The first one regards the design, characterization and performance evaluation of new passive and active microwave devices, sensors and measurement set-ups able to mitigate clutter and increase information content. The second line faces the requirements to make State-of-the-Art processing tools compliant with the instrumentations developed in the first line, suitable to work in electromagnetically complex scenarios and able to exploit the unexplored possibilities offered by new instrumentations. The main goals of the project are: 1) Development/improvement and characterization of new sensors and systems for active and passive microwave imaging; 2) Set up, analysis and validation of state of art/novel data processing approach for GPR in critical infrastructure and subsurface imaging; 3) Integration of state of art and novel imaging hardware and characterization approaches to tackle realistic situations in security, safety and subsurface prospecting applications; 4) Development and feasibility study of bio-radar technology (system and data processing) for vital signs detection and

  12. Effects of lignocellulosic composition and microwave power level on the gaseous product of microwave pyrolysis

    International Nuclear Information System (INIS)

    Huang, Yu-Fong; Chiueh, Pei-Te; Kuan, Wen-Hui; Lo, Shang-Lien

    2015-01-01

    Agricultural residues are abundant resources to produce renewable energy and valuable chemicals. This study focused on the effects of lignocellulosic composition and microwave power level on the gaseous product of microwave pyrolysis of agricultural residues. When agricultural residues were under microwave radiation within 10 min, the maximum temperatures of approximately 320, 420, and 530 °C were achieved at the microwave power levels of 300, 400, and 500 W, respectively. Gas yield increased with increasing microwave power level, whereas solid and liquid yields decreased. Besides, gaseous products with higher H 2 content and higher calorific values can be obtained at higher microwave power levels. In addition to microwave power level, lignocellulosic composition was also an important factor. H 2 and CO 2 yields increased with increasing hemicellulose content, whereas CH 4 and CO yields increased with increasing cellulose content. Four empirical equations were derived to present the contributions of lignocellulosic materials to the yields of gaseous components. - Highlights: • About 530 °C was reached within 10 min at a microwave power level of 500 W. • Gas yield increased with increasing microwave power level. • A high correlation between hemicellulose content and either H 2 or CO 2 yield. • A high correlation between cellulose content and either CH 4 or CO yield. • Empirical equations depict contribution of lignocellulosic content to gas yield

  13. Combined effect of microwave and activated carbon on the remediation of polychlorinated biphenyl-contaminated soil.

    Science.gov (United States)

    Liu, Xitao; Yu, Gang

    2006-04-01

    The application of microwave and activated carbon for the treatment of polychlorinated biphenyl (PCB) contaminated soil was explored in this study with a model compound of 2,4,5-trichlorobiphenyl (PCB29). PCB-contaminated soil was treated in a quartz reactor by microwave irradiation at 2450MHz with the addition of granular activated carbon (GAC). In this procedure, GAC acted as microwave absorbent for reaching high temperature and reductant for dechlorination. A sheltered type-K thermocouple was applied to record the temperature rising courses. It was shown that the addition of GAC could effectively promote the temperature rising courses. The determination of PCB residues in soil by gas chromatography (GC) revealed that rates of PCB removal were highly dependent on microwave power, soil moisture content, and the amount of GAC added. GC with mass spectrum (MS) detector and ion chromatography were employed for the analysis of degradation intermediates and chlorine ions, respectively. It was suggested that microwave irradiation with the assistance of activated carbon might be a potential technology for the remediation of PCB-contaminated soil.

  14. Remediation of soils contaminated with polychlorinated biphenyls by microwave-irradiated manganese dioxide

    International Nuclear Information System (INIS)

    Huang Guanyi; Zhao Ling; Dong Yuanhua; Zhang Qin

    2011-01-01

    The removal of polychlorinated biphenyls (PCBs) using microwave-irradiated manganese dioxide (MnO 2 ) in PCB-contaminated soils under different conditions is investigated. The removal of PCB77 in two actual soil samples exhibits strong pH-dependent behavior, and the removal efficiency is higher in acidic soil (Ali-Perudic Ferrosols) than that in neutral soil (Udic Argosols). The removal kinetics of PCB77 using microwave-irradiated MnO 2 under different experimental conditions fits a pseudo-first-order kinetic model well. Both the removal efficiency and the kinetic constant (k) values of PCB77 in Ali-Perudic Ferrosols considerably increase, although in a nonlinear fashion, as the initial amount of MnO 2 is increased, as the treated soil mass is increased, and as the microwave power is increased. The reactivity of three PCBs (PCB28, PCB77, and PCB118) did not present as a function of the degree of chlorination in the reaction with microwave-irradiated MnO 2 . The pronounced removal of three PCBs in contaminated soil (all above 95%) indicates that MnO 2 in combination with microwave irradiation is promising for technological applications that seek to remediate sites critically polluted with PCBs.

  15. Highly efficient isocyanate-free microwave-assisted synthesis of [6]-oligourea

    KAUST Repository

    Qaroush, Abdussalam K.

    2013-01-01

    A new eco-friendly, isocyanate-free, energy-saving method for the production of [6]-oligourea, utilizing a green carbonylating agent, viz. propylene carbonate, is reported. It comprises an organocatalyzed, microwave-assisted, solvent-free synthesis. Two modes of microwave-assisted synthesis, viz. dynamic and fixed energy modes, were applied. Upon optimization, the dynamic mode gave 79% yields of [6]-oligourea. On the other hand, almost quantitative yields were obtained using the fixed mode, within 20 min, at 10 W and with the same catalyst loading. Combination of both organocatalysis and microwave energy input appears to be a key issue for the efficiency of the reaction, with the fixed energy mode being best suited. It should be noted that all data reported are reproducible (due to the homogeneous microwave technology used by CEM Discover S-Class of microwave reactors). To the best of our knowledge, this is the best eco-friendly synthetic approach for the preparation of the title oligomers. It paves the way for using more of the biorenewable and sustainable chemicals as a feedstock for the production of polyureas. The oligomer produced was analyzed by EA, ATR-FTIR, XRD, 1H and 13CNMR. Furthermore, thermal properties of the resulting [6]-oligourea were analyzed using TGA and DSC. © The Royal Society of Chemistry 2013.

  16. Microwave Tokamak Experiment: An overview of the construction and checkout phase

    International Nuclear Information System (INIS)

    Lang, L.L.; Bell, H.H.

    1989-01-01

    At Lawrence Livermore National Laboratory (LLNL) we constructed and presently operate the Microwave Tokamak Experiment (MTX) to demonstrate the feasibility of using microwave pulses produced from a free electron laser (FEL) to provide electron cyclotron heating (ECH) for use in tokamaks, particularly high-field machines. The MTX consists primarily of the ALCATOR C tokamak and power supplies that were documented and disassembled at the Massachusetts Institute of Technology (MIT) and shipped to LLNL in April 1987. We made many additions, including a new primary power system from the magnetic Fusion Test Facility (MFTF) substation, a new commutation system, substantially upgraded seismic support system for earthquake loading, a fast controls system for use with the FEL, a new data-acquisition system, and a new vault facility. We checked out these systems and put them into operation in October 1988; we achieved the first plasma in November 1988. We have also constructed and installed the microwave transmission system and the local microwave system to be used with the FEL. These systems transmit the microwaves to MTX quasi-optically through an evacuated tube. The ongoing plasma operations, both with and without FEL heating, are described in a companion paper. 12 refs., 2 figs., 2 tabs

  17. Microwave calcination for plutonium immobilization and residue stabilization

    Energy Technology Data Exchange (ETDEWEB)

    Harris, M.J.; Rising, T.L.; Roushey, W.J.; Sprenger, G.S. [Kaiser-Hill Co., Golden, CO (United States)

    1995-12-01

    In the late 1980`s development was begun on a process using microwave energy to vitrify low level mixed waste sludge and transuranic mixed waste sludge generated in Building 374 at Rocky Flats. This process was shown to produce a dense, highly durable waste form. With the cessation of weapons production at Rocky Flats, the emphasis has changed from treatment of low level and TRU wastes to stabilizaiton of plutonium oxide and residues. This equipment is versatile and can be used as a heat source to calcine, react or vitrify many types of residues and oxides. It has natural economies in that it heats only the material to be treated, significantly reducing cycle times over conventional furnaces. It is inexpensive to operate in that most of the working components remain outside of any necessary contamination enclosure and therefore can easily be maintained. Limited testing has been successfully performed on cerium oxide (as a surrogate for plutonium oxide), surrogate electrorefining salts, surrogate residue sludge and residue ash. Future plans also include tests on ion exchange resins. In an attempt to further the usefullness of this technology, a mobile, self-contained microwave melting system is currently under development and expected to be operational at Rocky Flats Enviromental Technology Site by the 4th quarter of FY96.

  18. Microwave calcination for plutonium immobilization and residue stabilization

    International Nuclear Information System (INIS)

    Harris, M.J.; Rising, T.L.; Roushey, W.J.; Sprenger, G.S.

    1995-01-01

    In the late 1980's development was begun on a process using microwave energy to vitrify low level mixed waste sludge and transuranic mixed waste sludge generated in Building 374 at Rocky Flats. This process was shown to produce a dense, highly durable waste form. With the cessation of weapons production at Rocky Flats, the emphasis has changed from treatment of low level and TRU wastes to stabilizaiton of plutonium oxide and residues. This equipment is versatile and can be used as a heat source to calcine, react or vitrify many types of residues and oxides. It has natural economies in that it heats only the material to be treated, significantly reducing cycle times over conventional furnaces. It is inexpensive to operate in that most of the working components remain outside of any necessary contamination enclosure and therefore can easily be maintained. Limited testing has been successfully performed on cerium oxide (as a surrogate for plutonium oxide), surrogate electrorefining salts, surrogate residue sludge and residue ash. Future plans also include tests on ion exchange resins. In an attempt to further the usefullness of this technology, a mobile, self-contained microwave melting system is currently under development and expected to be operational at Rocky Flats Enviromental Technology Site by the 4th quarter of FY96

  19. Fast assembly of ordered block copolymer nanostructures through microwave annealing.

    Science.gov (United States)

    Zhang, Xiaojiang; Harris, Kenneth D; Wu, Nathanael L Y; Murphy, Jeffrey N; Buriak, Jillian M

    2010-11-23

    Block copolymer self-assembly is an innovative technology capable of patterning technologically relevant substrates with nanoscale precision for a range of applications from integrated circuit fabrication to tissue interfacing, for example. In this article, we demonstrate a microwave-based method of rapidly inducing order in block copolymer structures. The technique involves the usage of a commercial microwave reactor to anneal block copolymer films in the presence of appropriate solvents, and we explore the effect of various parameters over the polymer assembly speed and defect density. The approach is applied to the commonly used poly(styrene)-b-poly(methyl methacrylate) (PS-b-PMMA) and poly(styrene)-b-poly(2-vinylpyridine) (PS-b-P2VP) families of block copolymers, and it is found that the substrate resistivity, solvent environment, and anneal temperature all critically influence the self-assembly process. For selected systems, highly ordered patterns were achieved in less than 3 min. In addition, we establish the compatibility of the technique with directed assembly by graphoepitaxy.

  20. Global Warming and the Microwave Background

    Directory of Open Access Journals (Sweden)

    Robitaille P.-M.

    2009-04-01

    Full Text Available In the work, the importance of assigning the microwave background to the Earth is ad- dressed while emphasizing the consequences for global climate change. Climate mod- els can only produce meaningful forecasts when they consider the real magnitude of all radiative processes. The oceans and continents both contribute to terrestrial emis- sions. However, the extent of oceanic radiation, particularly in the microwave region, raises concerns. This is not only since the globe is covered with water, but because the oceans themselves are likely to be weaker emitters than currently believed. Should the microwave background truly be generated by the oceans of the Earth, our planet would be a much less efficient emitter of radiation in this region of the electromagnetic spectrum. Furthermore, the oceans would appear unable to increase their emissions in the microwave in response to temperature elevation, as predicted by Stefan’s law. The results are significant relative to the modeling of global warming.

  1. Microwave-assisted grinding of metallurgical coke

    International Nuclear Information System (INIS)

    Ruisanchez, E.; Juarez-Perez, E. J.; Arenillas, A.; Bermudez, J. M.; Menendez, J. A.

    2014-01-01

    Metallurgical cokes are composed of graphitic carbon (s2p2) and different inorganic compounds with very different capacities to absorb microwave radiation. Moreover, due to the electric conductivity shown by the metallurgical cokes, microwave radiation produces electric arcs or microplasmas, which gives rise to hot spots. Therefore, when these cokes are irradiated with microwaves some parts of the particle experiment a rapid heating, while some others do not heat at all. As a result of the different expansion and stress caused by thermal the shock, small cracks and micro-fissures are produced in the particle. The weakening of the coke particles, and therefore an improvement of its grind ability, is produced. This paper studies the microwave-assisted grinding of metallurgical coke and evaluates the grinding improvement and energy saving. (Author)

  2. Enhanced infrared transmission characteristics of microwave ...

    Indian Academy of Sciences (India)

    2017-09-22

    Sep 22, 2017 ... ods result in grain growth, which adversely influences the transmission .... dispersing the powder in methanol and allowing a drop of this to become dry on a ... out in a resistive–microwave hybrid furnace with silicon car-.

  3. Modulated microwave microscopy and probes used therewith

    Science.gov (United States)

    Lai, Keji; Kelly, Michael; Shen, Zhi-Xun

    2012-09-11

    A microwave microscope including a probe tip electrode vertically positionable over a sample and projecting downwardly from the end of a cantilever. A transmission line connecting the tip electrode to the electronic control system extends along the cantilever and is separated from a ground plane at the bottom of the cantilever by a dielectric layer. The probe tip may be vertically tapped near or at the sample surface at a low frequency and the microwave signal reflected from the tip/sample interaction is demodulated at the low frequency. Alternatively, a low-frequency electrical signal is also a non-linear electrical element associated with the probe tip to non-linearly interact with the applied microwave signal and the reflected non-linear microwave signal is detected at the low frequency. The non-linear element may be semiconductor junction formed near the apex of the probe tip or be an FET formed at the base of a semiconducting tip.

  4. Microwave integrated circuit for Josephson voltage standards

    Science.gov (United States)

    Holdeman, L. B.; Toots, J.; Chang, C. C. (Inventor)

    1980-01-01

    A microwave integrated circuit comprised of one or more Josephson junctions and short sections of microstrip or stripline transmission line is fabricated from thin layers of superconducting metal on a dielectric substrate. The short sections of transmission are combined to form the elements of the circuit and particularly, two microwave resonators. The Josephson junctions are located between the resonators and the impedance of the Josephson junctions forms part of the circuitry that couples the two resonators. The microwave integrated circuit has an application in Josephson voltage standards. In this application, the device is asymmetrically driven at a selected frequency (approximately equal to the resonance frequency of the resonators), and a d.c. bias is applied to the junction. By observing the current voltage characteristic of the junction, a precise voltage, proportional to the frequency of the microwave drive signal, is obtained.

  5. Mechanical characterization of microwave sintered zinc oxide

    Indian Academy of Sciences (India)

    Unknown

    ultrasonic time of flight measurement using a 15 MHz transducer. .... Figure 1. Microwave heating system (a. thermocouple, b. porous refractory box, c. sample, d. fibrous insulation material, e. power control, f. timer and g. display panel). a b c d.

  6. Microwave Radiometry and Radiometers for Ocean Applications

    DEFF Research Database (Denmark)

    Skou, Niels

    2008-01-01

    aperture radiometer technique, both yielding imaging capability without scanning. Typical applications of microwave radiometry concerning oceans are: sea salinity, sea surface temperature, wind speed and direction, sea ice detection and classification. However, in an attempt to measure properties...

  7. Direct reading fast microwave interferometer for EBT

    International Nuclear Information System (INIS)

    Uckan, T.

    1984-10-01

    A simple and inexpensive 4-mm direct reading fast (rise time approx. 100 μs) microwave interferometer is described. The system is particularly useful for density measurements on the ELMO Bumpy Torus (EBT) during pulsed operation

  8. Microwave Imaging for Breast Cancer Detection

    DEFF Research Database (Denmark)

    Rubæk, Tonny; Fhager, Andreas; Jensen, Peter Damsgaard

    2011-01-01

    Still more research groups are promoting microwave imaging as a viable supplement or substitution to more conventional imaging modalities. A widespread approach for microwave imaging of the breast is tomographic imaging in which one seeks to reconstruct the distributions of permittivity and condu......Still more research groups are promoting microwave imaging as a viable supplement or substitution to more conventional imaging modalities. A widespread approach for microwave imaging of the breast is tomographic imaging in which one seeks to reconstruct the distributions of permittivity...... and conductivity in the breast. In this paper two nonlinear tomographic algorithms are compared – one is a single-frequency algorithm and the other is a time-domain algorithm....

  9. Theory and design of microwave filters

    CERN Document Server

    Hunter, Ian

    2000-01-01

    This is a thorough, graduate-level text which provides a single source for filter design including basic circuit theory, network synthesis and the design of a variety of microwave filter structures. The aim is to present design theories followed by specific examples with numerical simulations of the designs, with pictures of real devices wherever possible. The book is aimed at designers, engineers and researchers working in microwave electronics who need to design or specify filters.

  10. Progress towards microwave spectroscopy of trapped antihydrogen

    CERN Document Server

    Ashkezari, M D; Baquero-Ruiz, M; Bertsche, W; Bowe, P D; Butler, E; Cesar, C L; Chapman, S; Charlton, M; Deller, A; Eriksson, S; Fajans, J; Friesen, T; Fujiwara, M C; Gill, D R; Gutierrez, A; Hangst, J S; Hardy, W N; Hayano, R S; Hayden, M E; Humphries, A J; Hydomako, R; Jonsell, S; Kurchaninov, L; Madsen, N; Menary, S; Nolan, P; Olchanski, K; Olin, A; Povilus, A; Pusa, P; Robicheaux, F; Sarid, E; Silveira, D M; So, C; Storey, J W; Thompson, R I; van der Werf, D P; Wurtele, J S; Yamazaki,Y

    2012-01-01

    Precision comparisons of hyperfine intervals in atomic hydrogen and antihydrogen are expected to yield experimental tests of the CPT theorem. The CERN-based ALPHA collaboration has initiated a program of study focused on microwave spectroscopy of trapped ground-state antihydrogen atoms. This paper outlines some of the proposed experiments, and summarizes measurements that characterize microwave fields that have been injected into the ALPHA apparatus.

  11. Progress towards microwave spectroscopy of trapped antihydrogen

    Energy Technology Data Exchange (ETDEWEB)

    Ashkezari, Mohammad D., E-mail: mdehghan@cern.ch [Simon Fraser University, Department of Physics (Canada); Andresen, Gorm B. [Aarhus University, Department of Physics and Astronomy (Denmark); Baquero-Ruiz, Marcelo [University of California, Department of Physics (United States); Bertsche, Wil [Swansea University, Department of Physics (United Kingdom); Bowe, Paul D. [Aarhus University, Department of Physics and Astronomy (Denmark); Butler, Eoin [CERN, Physics Department (Switzerland); Cesar, Claudio L. [Universidade Federal do Rio de Janeiro, Instituto de Fisica (Brazil); Chapman, Steve [University of California, Department of Physics (United States); Charlton, Michael; Deller, Adam; Eriksson, Stefan [Swansea University, Department of Physics (United Kingdom); Fajans, Joel [University of California, Department of Physics (United States); Friesen, Tim; Fujiwara, Makoto C. [University of Calgary, Department of Physics and Astronomy (Canada); Gill, Dave R. [TRIUMF (Canada); Gutierrez, Andrea [University of British Columbia, Department of Physics and Astronomy (Canada); Hangst, Jeffrey S. [Aarhus University, Department of Physics and Astronomy (Denmark); Hardy, Walter N. [University of British Columbia, Department of Physics and Astronomy (Canada); Hayano, Ryugo S. [University of Tokyo, Department of Physics (Japan); Hayden, Michael E. [Simon Fraser University, Department of Physics (Canada); Collaboration: ALPHA Collaboration; and others

    2012-12-15

    Precision comparisons of hyperfine intervals in atomic hydrogen and antihydrogen are expected to yield experimental tests of the CPT theorem. The CERN-based ALPHA collaboration has initiated a program of study focused on microwave spectroscopy of trapped ground-state antihydrogen atoms. This paper outlines some of the proposed experiments, and summarizes measurements that characterize microwave fields that have been injected into the ALPHA apparatus.

  12. Microwaves photonic links components and circuits

    CERN Document Server

    Rumelhard, Christian; Billabert, Anne-Laure

    2013-01-01

    This book presents the electrical models for the different elements of a photonic microwave link like lasers, external modulators, optical fibers, photodiodes and phototransistors. The future trends of these components are also introduced: lasers to VCSEL, external modulators to electro-absorption modulators, glass optical fibers to plastic optical fibers, photodiodes to UTC photodiodes or phototransistors. It also describes an original methodology to evaluate the performance of a microwave photonic link, based on the developed elcetrical models, that can be easily incorporated in

  13. Microwave detection of air showers with MIDAS

    Energy Technology Data Exchange (ETDEWEB)

    Facal San Luis, P., E-mail: facal@kicp.uchicago.edu [University of Chicago, Enrico Fermi Institue and Kavli Institute for Cosmological Physics, 5640 South Ellis Avenue, Chicago, IL 60637 (United States); Alekotte, I. [Centro Atomico Bariloche and Instituto Balseiro (CNEA-UNCuyo-CONICET), 8400 San Carlos de Bariloche, Rio Negro (Argentina); Alvarez, J. [Universidad de Santiago de Compostela, Departamento de Fisica de Particulas, Campus Sur, E-15782 Santiago de Compostela (Spain); Berlin, A. [University of Chicago, Enrico Fermi Institue and Kavli Institute for Cosmological Physics, 5640 South Ellis Avenue, Chicago, IL 60637 (United States); Bertou, X. [Centro Atomico Bariloche and Instituto Balseiro (CNEA-UNCuyo-CONICET), 8400 San Carlos de Bariloche, Rio Negro (Argentina); Bogdan, M.; Bohacova, M. [University of Chicago, Enrico Fermi Institue and Kavli Institute for Cosmological Physics, 5640 South Ellis Avenue, Chicago, IL 60637 (United States); Bonifazi, C. [Univ. Federal do Rio de Janeiro (UFRJ), Instituto de Fisica, Cidade Universitaria, Caixa Postal 68528, 21945-970 Rio de Janeiro, RJ (Brazil); Carvalho, W.R. [Universidad de Santiago de Compostela, Departamento de Fisica de Particulas, Campus Sur, E-15782 Santiago de Compostela (Spain); Mello Neto, J.R.T. de [Univ. Federal do Rio de Janeiro (UFRJ), Instituto de Fisica, Cidade Universitaria, Caixa Postal 68528, 21945-970 Rio de Janeiro, RJ (Brazil); Genat, J.F.; Mills, E.; Monasor, M.; Privitera, P.; Reyes, I.C.; Rouille d& #x27; Orfeuil, B. [University of Chicago, Enrico Fermi Institue and Kavli Institute for Cosmological Physics, 5640 South Ellis Avenue, Chicago, IL 60637 (United States); and others

    2012-01-11

    MIDAS (MIcrowave Detector of Air Showers) is a prototype of a microwave telescope to detect extensive air showers: it images a 20{sup Degree-Sign } Multiplication-Sign 10{sup Degree-Sign} region of the sky with a 4.5 m parabolic reflector and 53 feeds in the focal plane. It has been commissioned in March 2010 and is currently taking data. We present the design, performance and first results of MIDAS.

  14. Microwave detection of air showers with MIDAS

    International Nuclear Information System (INIS)

    Facal San Luis, P.; Alekotte, I.; Alvarez, J.; Berlin, A.; Bertou, X.; Bogdan, M.; Bohacova, M.; Bonifazi, C.; Carvalho, W.R.; Mello Neto, J.R.T. de; Genat, J.F.; Mills, E.; Monasor, M.; Privitera, P.; Reyes, I.C.; Rouille d’Orfeuil, B.

    2012-01-01

    MIDAS (MIcrowave Detector of Air Showers) is a prototype of a microwave telescope to detect extensive air showers: it images a 20 ° ×10 ° region of the sky with a 4.5 m parabolic reflector and 53 feeds in the focal plane. It has been commissioned in March 2010 and is currently taking data. We present the design, performance and first results of MIDAS.

  15. Isotherms clustering in cosmic microwave background

    International Nuclear Information System (INIS)

    Bershadskii, A.

    2006-01-01

    Isotherms clustering in cosmic microwave background (CMB) has been studied using the 3-year WMAP data on cosmic microwave background radiation. It is shown that the isotherms clustering could be produced by the baryon-photon fluid turbulence in the last scattering surface. The Taylor-microscale Reynolds number of the turbulence is estimated directly from the CMB data as Re λ ∼10 2

  16. Continuous microwave regeneration apparatus for absorption media

    Science.gov (United States)

    Smith, Douglas D.

    1999-01-01

    A method and apparatus for continuously drying and regenerating ceramic beads for use in process gas moisture drying operations such as glove boxes. A microwave energy source is coupled to a process chamber to internally heat the ceramic beads and vaporize moisture contained therein. In a preferred embodiment, the moisture laden ceramic beads are conveyed toward the microwave source by a screw mechanism. The regenerated beads flow down outside of the screw mechanism and are available to absorb additional moisture.

  17. Microwave sintering of hydroxyapatite-based composites

    International Nuclear Information System (INIS)

    Fang, Y.; Roy, D.M.; Cheng, J.; Roy, R.; Agrawal, D.K.

    1993-01-01

    Composites of hydroxyapatite/partially stabilized zirconia (HAp/PSZ) and hydroxyapatite/silicon carbide whiskers (HAp/SiC) were sintered at 1100-1200 degrees C by microwave at 2.45 GHz. Characterization of the sintered composites was carried out by density, microstructure, phase composition, and fracture toughness measurements. The results show that although not yet fully densified, a much higher sintered density in the HAp/PSZ composite was achieved by microwave sintering than by conventional sintering at the same temperature. A relative density of 93% was achieved by 20 min. microwave processing at 1200 degrees C. Comparatively, 2 h conventional sintering of the same material at 1200 degrees C led to only 75.5% relative density. K IC of this microwave sintered HAp/PSZ of 93% density was found to be 3.88 MPa√m, which is 250% of the value for pure HAp of the same density. A further increase in K IC could be expected if full or nearly full densification was achieved. Sintering of PSZ particles in the HAp/PSZ composite was also observed in the microwave processed sample. Microwave sintering of HAp/SiC was not successful in the current study due to the oxidation of SiC in air at high temperature. 8 refs., 4 figs., 1 tab

  18. Combination microwave ovens: an innovative design strategy.

    Science.gov (United States)

    Tinga, Wayne R; Eke, Ken

    2012-01-01

    Reducing the sensitivity of microwave oven heating and cooking performance to load volume, load placement and load properties has been a long-standing challenge for microwave and microwave-convection oven designers. Conventional design problem and solution methods are reviewed to provide greater insight into the challenge and optimum operation of a microwave oven after which a new strategy is introduced. In this methodology, a special load isolating and energy modulating device called a transducer-exciter is used containing an iris, a launch box, a phase, amplitude and frequency modulator and a coupling plate designed to provide spatially distributed coupling to the oven. This system, when applied to a combined microwave-convection oven, gives astounding performance improvements to all kinds of baked and roasted foods including sensitive items such as cakes and pastries, with the only compromise being a reasonable reduction in the maximum available microwave power. Large and small metal utensils can be used in the oven with minimal or no performance penalty on energy uniformity and cooking results. Cooking times are greatly reduced from those in conventional ovens while maintaining excellent cooking performance.

  19. Microwave Triggered Laser Ionization of Air

    Science.gov (United States)

    Vadiee, Ehsan; Prasad, Sarita; Jerald Buchenauer, C.; Schamiloglu, Edl

    2012-10-01

    The goal of this work is to study the evolution and dynamics of plasma expansion when a high power microwave (HPM) pulse is overlapped in time and space on a very small, localized region of plasma formed by a high energy laser pulse. The pulsed Nd:YAG laser (8 ns, 600mJ, repetition rate 10 Hz) is focused to generate plasma filaments in air with electron density of 10^17/cm^3. When irradiated with a high power microwave pulse these electrons would gain enough kinetic energy and further escalate avalanche ionization of air due to elastic electron-neutral collisions thereby causing an increased volumetric discharge region. An X-band relativistic backward wave oscillator(RBWO) at the Pulsed Power,Beams and Microwaves laboratory at UNM is constructed as the microwave source. The RBWO produces a microwave pulse of maximum power 400 MW, frequency of 10.1 GHz, and energy of 6.8 Joules. Special care is being given to synchronize the RBWO and the pulsed laser system in order to achieve a high degree of spatial and temporal overlap. A photodiode and a microwave waveguide detector will be used to ensure the overlap. Also, a new shadowgraph technique with a nanosecond time resolution will be used to detect changes in the shock wave fronts when the HPM signal overlaps the laser pulse in time and space.

  20. Characterization of a microwave generated plasma

    International Nuclear Information System (INIS)

    Root, D.J.; Mahoney, L.; Asmussen, J.

    1986-01-01

    Recent experiments have demonstrated a microwave ion beam source without and with static magnetic fields in inert gases and in oxygen gases. This plasma generation configuration also has uses in the areas of plasma processing such as plasma etching, plasma assisted thin flim deposition and plasma assisted oxide growth. These ion beam and plasma processing applications have provided motivation to investigate microwave discharge properties, such as electron density, electron temperature, gas temperature, degree of ionization, etc., of the microwave generated plasma over a wide range of experimental operating conditions. This paper presents the results of experimental measurements which attempt to characterize the experimental microwave discharge in the absence of a static magnetic field. Measurements from a double probe, which is located in the plasma in a zero microwave field region, are presented in argon, xenon and oxygen gases. Variations of plasma density and electron temperature versus absorbed microwave power, gas pressure (0.2 m Torr to 200 m Torr) and discharge diffusion length are presented and compared to dc positive column discharge theory