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Sample records for technology microwave sounder

  1. 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...

  2. The Advanced Technology Microwave Sounder (ATMS): The First 10 Months On-Orbit

    Science.gov (United States)

    Kim, Edward; Lyu, C-H Joseph; Blackwell, Willaim; Leslie, R. Vince; Baker, Neal; Mo, Tsan; Sun, Ninghai; Bi, Li; Anderson, Kent; Landrum, Mike; hide

    2012-01-01

    The Advanced Technology Microwave Sounder (ATMS) is a new satellite microwave sounding sensor designed to provide operational weather agencies with atmospheric temperature and moisture profile information for global weather forecasting and climate applications. A TMS will continue the microwave sounding capabilities first provided by its predecessors, the Microwave Sounding Unit (MSU) and Advanced Microwave Sounding Unit (AMSU). The first ATMS was launched October 28, 2011 on board the NPOESS Preparatory Project (NPP) satellite. Microwave soundings by themselves are the highest-impact input data used by Numerical Weather Prediction (NWP) models, especially under cloudy sky conditions. ATMS has 22 channels spanning 23-183 GHz, closely following the channel set of the MSU, AMSU-A1/2, AMSU-B, Microwave Humidity Sounder (MHS), and Humidity Sounder for Brazil (HSB). All this is accomplished with approximately 1/4 the volume, 1/2 the mass, and 1/2 the power of the three AMSUs. A description of ATMS cal/val activities will be presented followed by examples of its performance after its first 10 months on orbit.

  3. 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.

  4. The Advanced Technology Microwave Sounder (ATMS): First Year On-Orbit

    Science.gov (United States)

    Kim, Edward J.

    2012-01-01

    The Advanced Technology Microwave Sounder (ATMS) is a new satellite microwave sounding sensor designed to provide operational weather agencies with atmospheric temperature and moisture profile information for global weather forecasting and climate applications. A TMS will continue the microwave sounding capabilities first provided by its predecessors, the Microwave Sounding Unit (MSU) and Advanced Microwave Sounding Unit (AMSU). The first flight unit was launched a year ago in October, 2011 aboard the Suomi-National Polar-Orbiting Partnership (S-NPP) satellite, part of the new Joint Polar-Orbiting Satellite System (JPSS). Microwave soundings by themselves are the highest-impact input data used by Numerical Weather Prediction models; and A TMS, when combined with the Cross-track Infrared Sounder (CrIS), forms the Cross-track Infrared and Microwave Sounding Suite (CrIMSS). The microwave soundings help meet sounding requirements under cloudy sky conditions and provide key profile information near the surface. ATMS was designed & built by Aerojet Corporation in Azusa, California, (now Northrop Grumman Electronic Systems). It has 22 channels spanning 23-183 GHz, closely following the channel set of the MSU, AMSU-AI/2, AMSU-B, Microwave Humidity Sounder (MHS), and Humidity Sounder for Brazil (HSB). It continues their cross-track scanning geometry, but for the first time, provides Nyquist sample spacing. All this is accomplished with approximately V. the volume, Y, the mass, and Y, the power of the three AMSUs. A description will be given of its performance from its first year of operation as determined by post-launch calibration activities. These activities include radiometric calibration using the on-board warm targets and cold space views, and geolocation determination. Example imagery and zooms of specific weather events will be shown. The second ATMS flight model is currently under construction and planned for launch on the "Jl" satellite of the JPSS program in

  5. 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.

  6. 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,...

  7. 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...

  8. The Advanced Technology Microwave Sounder (ATMS): A New Operational Sensor Series

    Science.gov (United States)

    Kim, Edward; Lyu, Cheng-H Joseph; Leslie, R. Vince; Baker, Neal; Mo, Tsan; Sun, Ninghai; Bi, Li; Anderson, Mike; Landrum, Mike; DeAmici, Giovanni; hide

    2012-01-01

    ATMS is a new satellite microwave sounding sensor designed to provide operational weather agencies with atmospheric temperature and moisture profile information for global weather forecasting and climate applications. ATMS will continue the microwave sounding capabilities first provided by its predecessors, the Microwave Sounding Unit (MSU) and Advanced Microwave Sounding Unit (AMSU). The first ATMS was launched October 28, 2011 on board the Suomi National Polar-orbiting Partnership (S-NPP) satellite. Microwave soundings by themselves are the highest-impact input data used by Numerical Weather Prediction (NWP) models; and ATMS, when combined with the Cross-track Infrared Sounder (CrIS), forms the Cross-track Infrared and Microwave Sounding Suite (CrIMSS). The microwave soundings help meet NWP sounding requirements under cloudy sky conditions and provide key profile information near the surface

  9. Pre-Launch Radiometric Performance Characterization of the Advanced Technology Microwave Sounder on the Joint Polar Satellite System-1 Satellite

    Science.gov (United States)

    Smith, Craig K.; Kim, Edward; Leslie, R. Vincent; Lyu, Joseph; McCormick, Lisa M.; Anderson, Kent

    2017-01-01

    The Advanced Technology Microwave Sounder (ATMS) is a space-based, cross-track radiometer for operational atmospheric temperature and humidity sounding, utilizing 22 channels over a frequency range from 23 to 183 gigahertz. The ATMS for the Joint Polar Satellite System-1 has undergone two rounds of re-work in 2014-2015 and 2016, following performance issues discovered during and following thermal vacuum chamber (TVAC) testing at the instrument and observatory level. Final shelf-level testing, including measurement of pass band characteristics and spectral response functions, was completed in December 2016. Final instrument-level TVAC testing and calibration occurred during February 2017. Here we will describe the instrument-level TVAC calibration process, and illustrate with results from the final TVAC calibration effort.

  10. 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...

  11. UARS Microwave Limb Sounder (MLS) Level 3AL V001

    Data.gov (United States)

    National Aeronautics and Space Administration — The Microwave Limb Sounder (MLS) Level 3AL data product consists of daily, 4 degree increment latitude-ordered vertical profiles of temperature, geopotential height,...

  12. UARS Microwave Limb Sounder (MLS) Level 3AT V001

    Data.gov (United States)

    National Aeronautics and Space Administration — The Microwave Limb Sounder (MLS) Level 3AT data product consists of daily, 65.536 second interval time-ordered vertical profiles of temperature, geopotential height,...

  13. Special Sensor Microwave Imager/Sounder (SSMIS) Temperature Data Record (TDR) in netCDF

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Special Sensor Microwave Imager/Sounder (SSMIS) is a series of passive microwave conically scanning imagers and sounders onboard the DMSP satellites beginning...

  14. Special Sensor Microwave Imager/Sounder (SSMIS) Sensor Data Record (SDR) in netCDF

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Special Sensor Microwave Imager/Sounder (SSMIS) is a series of passive microwave conically scanning imagers and sounders onboard the DMSP satellites beginning...

  15. GEOSTAR - a microwave sounder for GOES-R

    Science.gov (United States)

    Lambrigtsen, Bjorn; Wilson, William; Tanner, Alan

    2005-01-01

    The National Oceanic and Atmospheric Administration (NOAA) has for many years operated two weather satellite systems, the Polar-orbiting Operational Environmental Satellite system (POES), using low-earth orbiting (LEO) satellites, and the Geostationary Operational Environmental Satellite system (GOES), using geostationary earth orbiting (GEO) satellites. Similar systems are also operated by other nations. The POES satellites have been equipped with both infrared (IR) and microwave (MW) atmospheric sounders, which together make it possible to determine the vertical distribution of temperature and humidity in the troposphere even under cloudy conditions.

  16. Noise performance of microwave humidity sounders over their lifetime

    Science.gov (United States)

    Hans, Imke; Burgdorf, Martin; John, Viju O.; Mittaz, Jonathan; Buehler, Stefan A.

    2017-12-01

    The microwave humidity sounders Special Sensor Microwave Water Vapor Profiler (SSMT-2), Advanced Microwave Sounding Unit-B (AMSU-B) and Microwave Humidity Sounder (MHS) to date have been providing data records for 25 years. So far, the data records lack uncertainty information essential for constructing consistent long time data series. In this study, we assess the quality of the recorded data with respect to the uncertainty caused by noise. We calculate the noise on the raw calibration counts from the deep space views (DSVs) of the instrument and the noise equivalent differential temperature (NEΔT) as a measure for the radiometer sensitivity. For this purpose, we use the Allan deviation that is not biased from an underlying varying mean of the data and that has been suggested only recently for application in atmospheric remote sensing. Moreover, we use the bias function related to the Allan deviation to infer the underlying spectrum of the noise. As examples, we investigate the noise spectrum in flight for some instruments. For the assessment of the noise evolution in time, we provide a descriptive and graphical overview of the calculated NEΔT over the life span of each instrument and channel. This overview can serve as an easily accessible information for users interested in the noise performance of a specific instrument, channel and time. Within the time evolution of the noise, we identify periods of instrumental degradation, which manifest themselves in an increasing NEΔT, and periods of erratic behaviour, which show sudden increases of NEΔT interrupting the overall smooth evolution of the noise. From this assessment and subsequent exclusion of the aforementioned periods, we present a chart showing available data records with NEΔT Fidelity and Uncertainty in Climate data records from Earth Observation (FIDUCEO).

  17. Noise performance of microwave humidity sounders over their lifetime

    Directory of Open Access Journals (Sweden)

    I. Hans

    2017-12-01

    Full Text Available The microwave humidity sounders Special Sensor Microwave Water Vapor Profiler (SSMT-2, Advanced Microwave Sounding Unit-B (AMSU-B and Microwave Humidity Sounder (MHS to date have been providing data records for 25 years. So far, the data records lack uncertainty information essential for constructing consistent long time data series. In this study, we assess the quality of the recorded data with respect to the uncertainty caused by noise. We calculate the noise on the raw calibration counts from the deep space views (DSVs of the instrument and the noise equivalent differential temperature (NEΔT as a measure for the radiometer sensitivity. For this purpose, we use the Allan deviation that is not biased from an underlying varying mean of the data and that has been suggested only recently for application in atmospheric remote sensing. Moreover, we use the bias function related to the Allan deviation to infer the underlying spectrum of the noise. As examples, we investigate the noise spectrum in flight for some instruments. For the assessment of the noise evolution in time, we provide a descriptive and graphical overview of the calculated NEΔT over the life span of each instrument and channel. This overview can serve as an easily accessible information for users interested in the noise performance of a specific instrument, channel and time. Within the time evolution of the noise, we identify periods of instrumental degradation, which manifest themselves in an increasing NEΔT, and periods of erratic behaviour, which show sudden increases of NEΔT interrupting the overall smooth evolution of the noise. From this assessment and subsequent exclusion of the aforementioned periods, we present a chart showing available data records with NEΔT  <  1 K. Due to overlapping life spans of the instruments, these reduced data records still cover without gaps the time since 1994 and may therefore serve as a first step for constructing long time

  18. GPM GROUND VALIDATION SPECIAL SENSOR MICROWAVE IMAGER/SOUNDER (SSMI/S) LPVEX V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The GPM Ground Validation Special Sensor Microwave Imager/Sounder (SSMI/S) LPVEx dataset contains brightness temperature data processed from the NOAA CLASS QC...

  19. Progress in developing GeoSTAR - Microwave Sounder for GOES-R

    Science.gov (United States)

    Lambrigtsen, Bjorn H.; Brown, S. T.; Dinardo, S. J.; Kangaslahti, P. P.; Tanner, A. B.; Wilson, W. J.

    2005-01-01

    The Geostationary Synthetic Thinned Aperture Radiometer (GeoSTAR)is a new concept for a microwave sounder, intended to be deployed at the Jet Propulsion Laboratory under NASA Instrument Incubator Program sponsorship, and is currently undergoing tests and performance characterization.

  20. UARS Microwave Limb Sounder (MLS) Level 3AL V005 (UARML3AL) at GES DISC

    Data.gov (United States)

    National Aeronautics and Space Administration — The Microwave Limb Sounder (MLS) Level 3AL data product consists of daily, 4 degree increment latitude-ordered vertical profiles of temperature, geopotential height,...

  1. UARS Microwave Limb Sounder (MLS) Level 3AT V005 (UARML3AT) at GES DISC

    Data.gov (United States)

    National Aeronautics and Space Administration — The Microwave Limb Sounder (MLS) Level 3AT data product consists of daily, 4 degree increment latitude-ordered vertical profiles of temperature, geopotential height,...

  2. Assimilation of Feng-Yun-3B satellite microwave humidity sounder data over land

    Science.gov (United States)

    Chen, Keyi; Bormann, Niels; English, Stephen; Zhu, Jiang

    2018-03-01

    The ECMWF has been assimilating Feng-Yun-3B (FY-3B) satellite microwave humidity sounder (MWHS) data over ocean in an operational forecasting system since 24 September 2014. It is more difficult, however, to assimilate microwave observations over land and sea ice than over the open ocean due to higher uncertainties in land surface temperature, surface emissivity and less effective cloud screening. We compare approaches in which the emissivity is retrieved dynamically from MWHS channel 1 [150 GHz (vertical polarization)] with the use of an evolving emissivity atlas from 89 GHz observations from the MWHS onboard NOAA and EUMETSAT satellites. The assimilation of the additional data over land improves the fit of short-range forecasts to other observations, notably ATMS (Advanced Technology Microwave Sounder) humidity channels, and the forecast impacts are mainly neutral to slightly positive over the first five days. The forecast impacts are better in boreal summer and the Southern Hemisphere. These results suggest that the techniques tested allow for effective assimilation of MWHS/FY-3B data over land.

  3. Nonlinear bias analysis and correction of microwave temperature sounder observations for FY-3C meteorological satellite

    Science.gov (United States)

    Hu, Taiyang; Lv, Rongchuan; Jin, Xu; Li, Hao; Chen, Wenxin

    2018-01-01

    The nonlinear bias analysis and correction of receiving channels in Chinese FY-3C meteorological satellite Microwave Temperature Sounder (MWTS) is a key technology of data assimilation for satellite radiance data. The thermal-vacuum chamber calibration data acquired from the MWTS can be analyzed to evaluate the instrument performance, including radiometric temperature sensitivity, channel nonlinearity and calibration accuracy. Especially, the nonlinearity parameters due to imperfect square-law detectors will be calculated from calibration data and further used to correct the nonlinear bias contributions of microwave receiving channels. Based upon the operational principles and thermalvacuum chamber calibration procedures of MWTS, this paper mainly focuses on the nonlinear bias analysis and correction methods for improving the calibration accuracy of the important instrument onboard FY-3C meteorological satellite, from the perspective of theoretical and experimental studies. Furthermore, a series of original results are presented to demonstrate the feasibility and significance of the methods.

  4. Scanning Mechanism of the FY-3 Microwave Humidity Sounder

    Science.gov (United States)

    Schmid, Manfred; Jing, Li; Hehr, Christian

    2010-01-01

    Astrium GmbH Germany, developed the scanning equipment for the instrument package of the MicroWave Humidity Sounder (MWHS) flying on the FY-3 meteorological satellite (FY means Feng Yun, Wind and Cloud) in a sun-synchronized orbit of 850-km altitude and at an inclination of 98.8 . The scanning mechanism rotates at variable velocity comprising several acceleration / deceleration phases during each revolution. The Scanning Mechanism contains two output shafts, each rotating a parabolic offset Antenna Reflector. The mechanism is operated in closed loop by means of redundant control electronics. MWHS is a sounding radiometer for measurement of global atmospheric water vapour profiles. An Engineering Qualification Model was developed and qualified and a first Flight Model was launched early 2008. The system is now working for more than two years successful in orbit. A second Flight Model of the Antenna Scanning Mechanism and of its associated control electronics was built and delivered to the customer for application on the follow-on spacecraft that will be launched by the end of 2010.

  5. Validation of Aura Microwave Limb Sounder HCl Measurements

    Science.gov (United States)

    Froidevaux, L.; Jiang, Y. B.; Lambert, A.; Livesey, N. J.; Read, W. G.; Waters, J. W.; Fuller, R. A.; Marcy, T. P.; Popp, P. J.; Gao, R. S.; hide

    2008-01-01

    The Earth Observing System (EOS) Microwave Limb Sounder (MLS) aboard the Aura satellite has provided daily global HCl profiles since August 2004. We provide a characterization of the resolution, random and systematic uncertainties, and known issues for the version 2.2 MLS HCl data. The MLS sampling allows for comparisons with many (1500 to more than 3000) closely matched profiles from the Halogen Occultation Experiment (HALOE) and Atmospheric Chemistry Experiment Fourier Transform Spectrometer (ACE-FTS). These data sets provide HCl latitudinal distributions that are, overall, very similar to those from (coincident) MLS profiles, although there are some discrepancies in the upper stratosphere between the MLS and HALOE gradients. As found in previous work, MLS and ACE HCl profiles agree very well (within approximately 5%, on average), but the MLS HCl abundances are generally larger (by 10-20%) than HALOE HCl. The bias versus HALOE is unlikely to arise mostly from MLS, as a similar systematic bias (of order 15%) is not observed between average MLS and balloon-borne measurements of HCl, obtained over Fort Sumner, New Mexico, in 2004 and 2005. At the largest pressure (147 hPa) for MLS HCl, a high bias (approximately 0.2 ppbv) is apparent in analyses of low to midlatitude data versus in situ aircraft chemical ionization mass spectrometry (CIMS) HCl measurements from the Aura Validation Experiment (AVE) campaigns in 2004, 2005, and 2006; this bias is also observed in comparisons of MLS and aircraftHCl/O3 correlations. Good agreement between MLS and CIMS HCl is obtained at 100 to 68 hPa. The recommended pressure range for MLS HCl is from 100 to 0.15 hPa.

  6. Tropical Cyclone Intensity and Position Analysis Using Passive Microwave Imager and Sounder Data

    Science.gov (United States)

    2015-03-26

    estimates derived from Polar-orbiting Opera- tional Environmental Satellite ( POES ) Advanced Microwave Sounding Unit (AMSU- A) brightness temperatures. This...upwelling microwave radiation. Microwave temperature sounder data from SSMI/S, ATMS and the Polar-orbiting Operational Environmental Satellite ( POES ...archive that pro- vides access to satellite data from NOAA POES , NPP, and DMSP (CLASS accessed 2014). A search interface provides options for spatial

  7. Evidence of Convective Redistribution of Carbon Monoxide in Aura Tropospheric Emission Sounder (TES) and Microwave Limb Sounder (MLS) Observations

    Science.gov (United States)

    Manyin, Michael; Douglass, Anne; Schoeberl, Mark

    2010-01-01

    Vertical convective transport is a key element of the tropospheric circulation. Convection lofts air from the boundary layer into the free troposphere, allowing surface emissions to travel much further, and altering the rate of chemical processes such as ozone production. This study uses satellite observations to focus on the convective transport of CO from the boundary layer to the mid and upper troposphere. Our hypothesis is that strong convection associated with high rain rate regions leads to a correlation between mid level and upper level CO amounts. We first test this hypothesis using the Global Modeling Initiative (GMI) chemistry and transport model. We find the correlation is robust and increases as the precipitation rate (the strength of convection) increases. We next examine three years of CO profiles from the Tropospheric Emission Sounder (TES) and Microwave Limb Sounder (MLS) instruments aboard EOS Aura. Rain rates are taken from the Tropical Rainfall Measuring Mission (TRMM) 3B-42 multi-satellite product. Again we find a correlation between mid-level and upper tropospheric CO, which increases with rain rate. Our result shows the critical importance of tropical convection in coupling vertical levels of the troposphere in the transport of trace gases. The effect is seen most clearly in strong convective regions such as the Inter-tropical Convergence Zone.

  8. Hyperspectral Microwave Atmospheric Sounder (HyMAS) architecture and design accommodations

    Science.gov (United States)

    Hilliard, L.; Racette, P.; Blackwell, W.; Galbraith, C.; Thompson, E.

    The Hyperspectral Microwave Atmospheric Sounder (HyMAS) is being developed at Lincoln Laboratories and accommodated by the Goddard Space Flight Center for a flight opportunity on a NASA research aircraft. The term “ hyperspectral microwave” is used to indicate an all-weather sounding that performs equivalent to hyperspectral infrared sounders in clear air with vertical resolution of approximately 1 km. Deploying the HyMAS equipped scanhead with the existing Conical Scanning Microwave Imaging Radiometer (CoSMIR) shortens the path to a flight demonstration. Hyperspectral microwave is achieved through the use of independent RF antennas that sample the volume of the Earth's atmosphere through various levels of frequencies, thereby producing a set of dense, spaced vertical weighting functions. The simulations proposed for HyMAS 118/183-GHz system should yield surface precipitation rate and water path retrievals for small hail, soft hail, or snow pellets, snow, rainwater, etc. with accuracies comparable to those of the Advanced Technology Microwave Sounder. Further improvements in retrieval methodology (for example, polarization exploitation) are expected. The CoSMIR instrument is a packaging concept re-used on HyMAS to ease the integration features of the scanhead. The HyMAS scanhead will include an ultra-compact Intermediate Frequency Processor (IFP) module that is mounted inside the door to improve thermal management. The IFP is fabricated with materials made of Low-Temperature Co-fired Ceramic (LTCC) technology integrated with detectors, amplifiers, A/D conversion and data aggregation. The IFP will put out 52 channels of 16 bit data comprised of 4 - 9 channel data streams for temperature profiles and 2-8 channel streams for water vapor. With the limited volume of the existing CoSMIR scanhead and new HyMAS front end components, the HyMAS team at Goddard began preliminary layout work inside the new drum. Importing and re-using models of the shell, the s- an head

  9. Design and Implementation of a Mechanical Control System for the Scanning Microwave Limb Sounder

    Science.gov (United States)

    Bowden, William

    2011-01-01

    The Scanning Microwave Limb Sounder (SMLS) will use technological improvements in low noise mixers to provide precise data on the Earth's atmospheric composition with high spatial resolution. This project focuses on the design and implementation of a real time control system needed for airborne engineering tests of the SMLS. The system must coordinate the actuation of optical components using four motors with encoder readback, while collecting synchronized telemetric data from a GPS receiver and 3-axis gyrometric system. A graphical user interface for testing the control system was also designed using Python. Although the system could have been implemented with a FPGA-based setup, we chose to use a low cost processor development kit manufactured by XMOS. The XMOS architecture allows parallel execution of multiple tasks on separate threads-making it ideal for this application and is easily programmed using XC (a subset of C). The necessary communication interfaces were implemented in software, including Ethernet, with significant cost and time reduction compared to an FPGA-based approach. For these reasons, the XMOS technology is an attractive, cost effective, alternative to FPGA-based technologies for this design and similar rapid prototyping projects.

  10. Polarization signature from the FengYun-3 Microwave Humidity Sounder

    Science.gov (United States)

    Zou, Xiaolei; Chen, Xu; Weng, Fuzhong

    2014-12-01

    Microwave Humidity Sounders (MHS) onboard NOAA-15, -16, -17, -18, -19, and EUMETSAT MetOp-A/B satellites provide radiance measurements at a single polarization state at any of five observed frequencies. The Microwave Humidity Sounder (MWHS) onboard the FengYun-3 (FY-3) satellite has a unique instrument design that provides dual polarization measurements at 150 GHz. In this study, the MWHS polarization signal was investigated using observed and modeled data. It is shown that the quasi-polarization brightness temperatures at 150 GHz display a scan angle dependent bias. Under calm ocean conditions, the polarization difference at 150 GHz becomes non-negligible when the scan angle varies from 10° to 45° and reaches a maximum when the scan angle is about 30°. Also, the polarization state is sensitive to surface parameters such as surface wind speed. Under clear-sky conditions, the differences between horizontal and vertical polarization states at 150 GHz increase with decreasing surface wind speed. Therefore, the polarization signals from the cross-track scanning microwave measurements at window channels contain useful information about surface parameters. In addition, the availability of dual polarization measurements allows a one-to-one conversion from antenna brightness temperature to sensor brightness temperature if a cross-polarization spill-over exists.

  11. Real-time Monitoring of Hurricanes with the HAMSR Microwave Sounder

    Science.gov (United States)

    Lambrigtsen, B.; Brown, S. T.; Lim, B.; Hristova-Veleva, S. M.; Li, P.; Knosp, B.; Turk, F. J.; Niamsuwan, N.

    2016-12-01

    The High Altitude MMIC Sounding Radiometer (HAMSR) is a 25-channel microwave sounder developed at the Jet Propulsion Laboratory to observe the atmosphere and in particular hurricanes from aircraft. Vertical profiles of temperature, water vapor and reflectivity, and cloud liquid water are derived from the measurements. It was initially flown on the NASA high-altitude piloted ER-2 aircraft, and the data were recorded during flight and downloaded and analyzed after landing, resulting in a latency of typically 8-24 hours. Later it was adapted for the NASA DC-8, where operators on the plane were able to monitor the data in real time through an on-board network, but limited communications with the ground prevented dissemination of data until after landing. A large change took place in 2010, when HAMSR was modified to fly on an unpiloted Global Hawk that NASA had recently acquired. This plane, which operates autonomously under supervision of pilots on the ground, has several communications systems that can be used to transmit data to the ground in real time. The most capable of those is a Ku-band link to geostationary communications satellites, which permits all HAMSR data to be transmitted in real time. A less capable system uses Iridium and only permits a subset of data to be transmitted. Since 2010 HAMSR has flown in a number of NASA and NOAA field campaigns on board the Global Hawk. The data is processed as it arrives at a ground server and almost immediately disseminated to a number of destinations. Primary among those is a web server developed at JPL, which displays the HAMSR data in conjunction with the most recent satellite data and forecast data and allows real-time analysis of model performance and identification of model errors. The data are also shared with the National Hurricane Center, where it can be used to help pinpoint the location of the center of a hurricane, which is particularly useful when the convection is poorly organized and the center ill

  12. Observation of the exhaust plume from the space shuttle main engines using the microwave limb sounder

    Directory of Open Access Journals (Sweden)

    H. C. Pumphrey

    2011-01-01

    Full Text Available A space shuttle launch deposits 700 tonnes of water in the atmosphere. Some of this water is released into the upper mesosphere and lower thermosphere where it may be directly detected by a limb sounding satellite instrument. We report measurements of water vapour plumes from shuttle launches made by the Microwave Limb Sounder (MLS on the Aura satellite. Approximately 50%–65% of shuttle launches are detected by MLS. The signal appears at a similar level across the upper 10 km of the MLS limb scan, suggesting that the bulk of the observed water is above the top of the scan. Only a small fraction at best of smaller launches (Ariane 5, Proton are detected. We conclude that the sensitivity of MLS is only just great enough to detect a shuttle sized launch, but that a suitably designed instrument of the same general type could detect the exhausts from a large proportion of heavy-lift launches.

  13. The Impact of Upper Tropospheric Humidity from Microwave Limb Sounder on the Midlatitude Greenhouse Effect

    Science.gov (United States)

    Hu, Hua; Liu, W. Timothy

    1998-01-01

    This paper presents an analysis of upper tropospheric humidity, as measured by the Microwave Limb Sounder, and the impact of the humidity on the greenhouse effect in the midlatitudes. Enhanced upper tropospheric humidity and an enhanced greenhouse effect occur over the storm tracks in the North Pacific and North Atlantic. In these areas, strong baroclinic activity and the large number of deep convective clouds transport more water vapor to the upper troposphere, and hence increase greenhouse trapping. The greenhouse effect increases with upper tropospheric humidity in areas with a moist upper troposphere (such as areas over storm tracks), but it is not sensitive to changes in upper tropospheric humidity in regions with a dry upper troposphere, clearly demonstrating that there are different mechanisms controlling the geographical distribution of the greenhouse effect in the midlatitudes.

  14. Atmospheric Sounder Spectrometer for Infrared Spectral Technology (ASSIST) Instrument Handbook

    Energy Technology Data Exchange (ETDEWEB)

    Flynn, Connor J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States). Atmospheric Radiation Measurement (ARM) Program

    2016-03-01

    The Atmospheric Sounder Spectrometer for Infrared Spectral Technology (ASSIST) measures the absolute infrared (IR) spectral radiance (watts per square meter per steradian per wavenumber) of the sky directly above the instrument. More information about the instrument can be found through the manufacturer’s website. The spectral measurement range of the instrument is 3300 to 520 wavenumbers (cm-1) or 3-19.2 microns for the normal-range instruments and 3300 to 400 cm-1 or 3-25 microns, for the extended-range polar instruments. Spectral resolution is 1.0 cm-1. Instrument field-of-view is 1.3 degrees. Calibrated sky radiance spectra are produced on cycle of about 141 seconds with a group of 6 radiance spectra zenith having dwell times of about 14 seconds each interspersed with 55 seconds of calibration and mirror motion. The ASSIST data is comparable to the Atmospheric Emitted Radiance Interferometer (AERI) data and can be used for 1) evaluating line-by-line radiative transport codes, 2) detecting/quantifying cloud effects on ground-based measurements of infrared spectral radiance (and hence is valuable for cloud property retrievals), and 3) calculating vertical atmospheric profiles of temperature and water vapor and the detection of trace gases.

  15. Assessments of F16 Special Sensor Microwave Imager and Sounder Antenna Temperatures at Lower Atmospheric Sounding Channels

    OpenAIRE

    Banghua Yan; Fuzhong Weng

    2009-01-01

    The main reflector of the Special Sensor Microwave Imager/Sounder (SSMIS) aboard the Defense Meteorological Satellite Program (DMSP) F-16 satellite emits variable radiation, and the SSMIS warm calibration load is intruded by direct and indirect solar radiation. These contamination sources produce antenna brightness temperature anomalies of around 2 K at SSMIS sounding channels which are obviously inappropriate for assimilation into numerical weather prediction models and remote sensing retrie...

  16. Validation of Aura Microwave Limb Sounder stratospheric water vapor measurements by the NOAA frost point hygrometer.

    Science.gov (United States)

    Hurst, Dale F; Lambert, Alyn; Read, William G; Davis, Sean M; Rosenlof, Karen H; Hall, Emrys G; Jordan, Allen F; Oltmans, Samuel J

    2014-02-16

    Differences between stratospheric water vapor measurements by NOAA frost point hygrometers (FPHs) and the Aura Microwave Limb Sounder (MLS) are evaluated for the period August 2004 through December 2012 at Boulder, Colorado, Hilo, Hawaii, and Lauder, New Zealand. Two groups of MLS profiles coincident with the FPH soundings at each site are identified using unique sets of spatiotemporal criteria. Before evaluating the differences between coincident FPH and MLS profiles, each FPH profile is convolved with the MLS averaging kernels for eight pressure levels from 100 to 26 hPa (~16 to 25 km) to reduce its vertical resolution to that of the MLS water vapor retrievals. The mean FPH - MLS differences at every pressure level (100 to 26 hPa) are well within the combined measurement uncertainties of the two instruments. However, the mean differences at 100 and 83 hPa are statistically significant and negative, ranging from -0.46 ± 0.22 ppmv (-10.3 ± 4.8%) to -0.10 ± 0.05 ppmv (-2.2 ± 1.2%). Mean differences at the six pressure levels from 68 to 26 hPa are on average 0.8% (0.04 ppmv), and only a few are statistically significant. The FPH - MLS differences at each site are examined for temporal trends using weighted linear regression analyses. The vast majority of trends determined here are not statistically significant, and most are smaller than the minimum trends detectable in this analysis. Except at 100 and 83 hPa, the average agreement between MLS retrievals and FPH measurements of stratospheric water vapor is better than 1%.

  17. Evolution of Satellite Imagers and Sounders for Low Earth Orbit and Technology Directions at NASA

    Science.gov (United States)

    Pagano, Thomas S.; McClain, Charles R.

    2010-01-01

    Imagers and Sounders for Low Earth Orbit (LEO) provide fundamental global daily observations of the Earth System for scientists, researchers, and operational weather agencies. The imager provides the nominal 1-2 km spatial resolution images with global coverage in multiple spectral bands for a wide range of uses including ocean color, vegetation indices, aerosol, snow and cloud properties, and sea surface temperature. The sounder provides vertical profiles of atmospheric temperature, water vapor cloud properties, and trace gases including ozone, carbon monoxide, methane and carbon dioxide. Performance capabilities of these systems has evolved with the optical and sensing technologies of the decade. Individual detectors were incorporated on some of the first imagers and sounders that evolved to linear array technology in the '80's. Signal-to-noise constraints limited these systems to either broad spectral resolution as in the case of the imager, or low spatial resolution as in the case of the sounder. Today's area 2-dimensional large format array technology enables high spatial and high spectral resolution to be incorporated into a single instrument. This places new constraints on the design of these systems and enables new capabilities for scientists to examine the complex processes governing the Earth System.

  18. CubeSat infrared atmospheric sounder (CIRAS) NASA InVEST technology demonstration

    Science.gov (United States)

    Pagano, Thomas S.

    2017-02-01

    Infrared sounders measure the upwelling radiation of the Earth in the Midwave Infrared (MWIR) and Longwave Infrared (LWIR) region of the spectrum with global daily coverage from space. The observed radiances are assimilated into weather forecast models and used to retrieve lower tropospheric temperature and water vapor for climate studies. There are several operational sounders today including the Atmospheric Infrared Sounder (AIRS) on Aqua, the Crosstrack Infrared Sounder (CrIS) on Suomi NPP and JPSS, and the Infrared Atmospheric Sounding Interferometer (IASI) on the MetOp spacecraft. The CubeSat Infrared Atmospheric Sounder (CIRAS) is a NASA In-flight Validation of Earth Science Technologies (InVEST) program to demonstrate three new instrument technologies in an imaging sounder configuration. The first is a 2D array of High Operating Temperature Barrier Infrared Detector (HOT-BIRD) material, selected for its high uniformity, low cost, low noise and higher operating temperatures than traditional materials. The detectors are hybridized to a commercial ROIC and commercial camera electronics. The second technology is a MWIR Grating Spectrometer (MGS) designed to provide imaging spectroscopy for atmospheric sounding in a CubeSat volume. The MGS employs an immersion grating or grism, has no moving parts, and is based on heritage spectrometers including the OCO- 2. The third technology is a Black Silicon infrared blackbody calibration target. The Black Silicon offers very low reflectance over a broad spectral range on a flat surface and is more robust than carbon nanotubes. JPL will also develop the mechanical, electronic and thermal subsystems for the CIRAS payload. The spacecraft will be a commercially available CubeSat. The integrated system will be a complete 6U CubeSat capable of measuring temperature and water vapor profiles with good lower tropospheric sensitivity. The low cost of CIRAS enables multiple units to be flown to improve temporal coverage or measure 3D

  19. A new 147-56 hPa water vapor product from the UARS Microwave Limb Sounder

    Science.gov (United States)

    Read, W. G.; Wu, D. L.; Waters, J. W.; Pumphrey, H. C.

    2004-03-01

    Measurements of H2O in the tropopause region have been obtained by production of a new data set from the Microwave Limb Sounder (MLS) on the Upper Atmosphere Research Satellite (UARS). A modified version of the retrieval scheme used to produce upper tropospheric humidity (UTH) from the MLS 203 GHz radiometer was applied to the MLS 183 GHz radiometer measurements to produce useful H2O data at 147, 121, 100, 83, 68, and 56 hPa. These new data, for the first 18 months of the UARS mission when the MLS 183 GHz radiometer was operational, fill an important "gap" around 100 hPa where previous MLS H2O data were generally not useful. Characteristics of the new data set are discussed and compared with National Oceanic and Atmospheric Administration (NOAA), Climate Monitoring and Diagnostics Laboratory (CMDL) frost-point hygrometer, and UARS Halogen Occultation Experiment (HALOE) measurements.

  20. 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.

  1. Direct assimilation of Chinese FY-3C Microwave Temperature Sounder-2 radiances in the global GRAPES system

    Science.gov (United States)

    Li, Juan; Liu, Guiqing

    2016-07-01

    FengYun-3C (FY-3C) is an operational polar-orbiting satellite carrying the new-generation microwave sounding instruments in China. This paper describes the assimilation of the FY-3C Microwave Temperature Sounder-2 (MWTS-2) radiances in the Global and Regional Assimilation and PrEdiction System (GRAPES) of China Meteorological Administration. A quality control (QC) procedure for the assimilation of MWTS-2 radiance is proposed. Extensive monitoring before assimilation shows that MWTS-2 observations exhibit a clear striping pattern. A technique combining principal component analysis (PCA) and ensemble empirical mode decomposition (EEMD) is applied to the observations to remove the striping noise. Cloudy field-of-views (FOVs) are identified by applying the Visible and InfrarRed Radiometer (VIRR) cloud fraction threshold of 76 %. Other QC steps are conducted in the follow order: (i) coastal FOVs are removed, (ii) eight outmost FOVs are not used, (iii) channel 5 data over sea ice and land are not used, (iv) channel 6 observations are not used if the terrain altitudes are higher than 500 m, and (v) outliers with large differences between observations and model simulations are removed. Approximately 83, 75, 40, and 40 % of the observations are removed by the proposed QC for channels 5-8, respectively. After QC, the global biases and standard deviations are reduced significantly. The assimilation of the MWTS-2 radiances shows a positive impact when the control experiment assimilates only conventional observations. The experiments also show that the analysis and forecast errors are slightly reduced when the striping noise is removed from the observations. The quality control scheme of extracting the striping noise may contribute to the analysis and forecast accuracy. The impact of MWTS-2 is neutral when the conventional data and other satellite data are all assimilated.

  2. Aura Microwave Limb Sounder Observations of Dynamics and Transport During the Record-Breaking 2009 Arctic Stratospheric Major Warming

    Science.gov (United States)

    Manney, Gloria L.; Schwartz, Michael J.; Krueger, Kirstin; Santee, Michelle L.; Pawson, Steven; Lee, Jae N.; Daffer, William H.; Fuller, Ryan A.; Livesey, Nathaniel J.

    2009-01-01

    A major stratospheric sudden warming (SSW) in January 2009 was the strongest and most prolonged on record. Aura Microwave Limb Sounder (MLS) observations are used to provide an overview of dynamics and transport during the 2009 SSW, and to compare with the intense, long-lasting SSW in January 2006. The Arctic polar vortex split during the 2009 SSW, whereas the 2006 SSW was a vortex displacement event. Winds reversed to easterly more rapidly and reverted to westerly more slowly in 2009 than in 2006. More mixing of trace gases out of the vortex during the decay of the vortex fragments, and less before the fulfillment of major SSW criteria, was seen in 2009 than in 2006; persistent well-defined fragments of vortex and anticyclone air were more prevalent in 2009. The 2009 SSW had a more profound impact on the lower stratosphere than any previously observed SSW, with no significant recovery of the vortex in that region. The stratopause breakdown and subsequent reformation at very high altitude, accompanied by enhanced descent into a rapidly strengthening upper stratospheric vortex, were similar in 2009 and 2006. Many differences between 2006 and 2009 appear to be related to the different character of the SSWs in the two years.

  3. Assessments of F16 Special Sensor Microwave Imager and Sounder Antenna Temperatures at Lower Atmospheric Sounding Channels

    Directory of Open Access Journals (Sweden)

    Banghua Yan

    2009-01-01

    Full Text Available The main reflector of the Special Sensor Microwave Imager/Sounder (SSMIS aboard the Defense Meteorological Satellite Program (DMSP F-16 satellite emits variable radiation, and the SSMIS warm calibration load is intruded by direct and indirect solar radiation. These contamination sources produce antenna brightness temperature anomalies of around 2 K at SSMIS sounding channels which are obviously inappropriate for assimilation into numerical weather prediction models and remote sensing retrievals of atmospheric and surface parameters. In this study, antenna brightness temperature anomalies at several lower atmospheric sounding (LAS channels are assessed, and the algorithm is developed for corrections of these antenna temperature anomalies. When compared against radiative transfer model simulations and simultaneous observations from AMSU-A aboard NOAA-16, the SSMIS antenna temperatures at 52.8, 53.6, 54.4, 55.5, 57.3, and 59.4 GHz after the anomaly correction exhibit small residual errors (<0.5 K. After such SSMIS antenna temperatures are applied to the National Center for Environmental Prediction Numerical Weather Prediction (NWP model, more satellite data is used and the analysis field of the geopotential height is significantly improved throughout troposphere and lower stratosphere. Therefore, the SSMIS antenna temperatures after the anomaly correction have demonstrated their potentials in NWP models.

  4. A Network of Direct Broadcast Antenna Systems to Provide Real-Time Infrared and Microwave Sounder Data for Numerical Weather Prediction

    Science.gov (United States)

    Gumley, L.

    2013-12-01

    The Space Science and Engineering Center at the University of Wisconsin-Madison is creating a network of direct broadcast satellite data reception stations to acquire and process infrared and microwave sounder data in real-time from polar orbiting meteorological satellites and deliver the resulting products to NOAA with low latency for assimilation in NCEP numerical weather prediction models. The network will include 4 antenna sites that will be operated directly by SSEC, including Madison WI, Honolulu HI, Miami FL, and Mayaguez PR. The network will also include partner antenna sites not directly controlled by SSEC, including Corvallis OR, Monterey CA, Suitland MD, Fairbanks AK, and Guam. All of the antenna sites will have a combined X/L-band reception system capable of receiving data via direct broadcast from polar orbiting satellites including Suomi NPP and JPSS-1, Metop-A/B, POES,Terra, and Aqua. Each site will collect raw data from these satellites locally, process it to Level 1 (SDR) and Level 2 (EDR) products, and transmit the products back to SSEC for delivery to NOAA/NCEP. The primary purpose of the antenna systems is to provide real-time infrared and microwave sounder data from Metop and Suomi-NPP to NOAA to support data assimilation for NOAA/NCEP operational numerical weather prediction models. At present, NOAA/NCEP use of advanced infrared (CrIS, IASI, AIRS) and microwave (ATMS, AMSU) sounder data over North America in NWP data assimilation is limited because of the latency of the products in relation to the cutoff times for assimilation runs. This network will deliver infrared and microwave sounder data to NCEP with the lowest latency possible, via the reception and processing of data received via direct broadcast. CIMSS/SSEC is managing the procurement and installation of the antenna systems at the two new sites, and will operate the stations remotely. NOAA will establish the reception priorities (Metop and SNPP will be at the highest priority) and

  5. An extended Kalman-Bucy filter for atmospheric temperature profile retrieval with a passive microwave sounder

    Science.gov (United States)

    Ledsham, W. H.; Staelin, D. H.

    1978-01-01

    An extended Kalman-Bucy filter has been implemented for atmospheric temperature profile retrievals from observations made using the Scanned Microwave Spectrometer (SCAMS) instrument carried on the Nimbus 6 satellite. This filter has the advantage that it requires neither stationary statistics in the underlying processes nor linear production of the observed variables from the variables to be estimated. This extended Kalman-Bucy filter has yielded significant performance improvement relative to multiple regression retrieval methods. A multi-spot extended Kalman-Bucy filter has also been developed in which the temperature profiles at a number of scan angles in a scanning instrument are retrieved simultaneously. These multi-spot retrievals are shown to outperform the single-spot Kalman retrievals.

  6. 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.

  7. An improved fast radiative transfer model for special sensor microwave imager/sounder upper atmosphere sounding channels

    Science.gov (United States)

    Han, Yong; van Delst, Paul; Weng, Fuzhong

    2010-08-01

    Special sensor microwave imager/sounder (SSMIS) on board the U. S. Defense Meteorology Satellite Program satellites includes six upper atmosphere sounding (UAS) channels for probing air temperature in the upper stratosphere and mesosphere. Three of the UAS channels 19-21 are sensitive to the Doppler frequency shift due to Earth's rotation. The sensitivity to the frequency shift in large degree depends on the O2 Zeeman splitting effect, which is a function of the Earth's magnetic field strength and the angle between the Earth's magnetic field and propagation direction of the electromagnetic wave. Since the brightness temperatures can change up to 2 K as a result of the Doppler shift, the fast radiative transfer model developed earlier for the SSMIS UAS channels has recently been improved to take the Doppler shift into account. In the fast model, an averaged transmittance within the channel frequency passbands is parameterized and trained with a line-by-line radiative transfer model that accurately computes the monochromatic transmittances at fine frequency steps within each passband. The model is evaluated by comparing it with the line-by-line model in an independent experiment. The root mean square differences between the two models are 0.21, 0.39, 0.34, and 0.19 K for channels 19-22, respectively. Using the model, the sensitivities of the radiances to the Doppler shift are analyzed through simulations. A theoretical explanation is given for the dependence of the sensitivities on the Zeeman splitting effect. Results from the analysis are then compared to the observations and a good agreement is achieved.

  8. The CubeSat Infrared Atmospheric Sounder (CIRAS): Demonstrating key technologies for a future constellation to improve temporal sampling

    Science.gov (United States)

    Pagano, T. S.

    2016-12-01

    Hyperspectral infrared sounding of the atmosphere has become a vital element in the observational system for weather forecast prediction at National Weather Prediction (NWP) centers worldwide. The NASA Atmospheric Infrared Sounder (AIRS) instrument was the pathfinder for the hyperspectral infrared observations and was designed to provide accurate atmospheric temperature and water vapor profile information in support of weather prediction. AIRS was launched in 2002 and continues to operate well. The Cross-track Infrared Sounder (CrIS) on the Suomi NPP satellite was launched in 2011 to continue the AIRS measurement record. CrIS also continues to operate well and additional sensors are planned for launch promising to continue the hyperspectral infrared measurements in support of NWP into the late 2030's. The high cost of IR sounders makes it costly to launch them into multiple orbits to improve temporal sampling, or into GEO, although EUMETSAT is planning a GEO IR Sounder to launch in the early 2020's. JPL NASA is offering an alternate hyperspectral IR sounder architecture for the future involving CubeSats. The latest technology in large format focal plane assemblies, wide field optics and active cryocoolers enables a reduction in size, mass and cost of the legacy sounders and offer new configurations. Lessons learned from AIRS and CrIS indicate that temperature and water vapor sounding in the lower troposphere can be achieved with only the MWIR portion of the spectrum. The CubeSat Infrared Atmospheric Sounder (CIRAS) employs only an MWIR spectrometer to achieve lower tropospheric temperature and water vapor profiles, but with comparable spatial, spectral and radiometric sensitivity in this band as AIRS and CrIS. CIRAS operates from 4.08-5.13 µm with 625 channels and spectral resolution of 1.2-2.0 cm-1. CIRAS employs an immersion grating spectrometer making the optics incredibly compact, and HOT-BIRD detectors enabling good uniformity and operability over the large

  9. 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,

  10. Assimilation of Chinese Fengyun-3B Microwave Temperature Sounder radiances into the Global GRAPES system with an improved cloud detection threshold

    Science.gov (United States)

    Li, Juan; Liu, Guiqing

    2016-03-01

    Fengyun-3B (FY-3B) is the second polar-orbiting satellite in the new Fengyun-three series. This paper describes the assimilation of the FY-3B Microwave Temperature Sounder (MWTS) radiances in the Chinese Numerical Weather prediction system — the Global and Regional Assimilation and PrEdiction System (GRAPES). A quality control procedure for the assimilation of the FY-3B MWTS radiance was proposed. Extensive monitoring before assimilation shows that the observations of channel 4 are notably contaminated. Channels 2 and 3 are used in this research. A cloud detection algorithm with an improved cloud-detection threshold is determined and incorporated into the impact experiments. The clear field-of-view (FOV) percentage increased from 42% to 57% with the new threshold. In addition, the newly added FOVs are located in the clear region, as demonstrated by the cloud liquid water path data from NOAA-18. The impact of the MWTS radiances on the prediction of GRAPES was researched. The observation biases of FY-3B MWTS O-B (differences between satellite observations and model simulations) significantly decreased after an empirical bias correction procedure. After assimilation, the residual biases are small. The assimilation of the FY-3B MWTS radiances shows a positive impact in the Northern Hemisphere and a neutral impact in the Southern Hemisphere.

  11. Constraining the chlorine monoxide (ClO)/chlorine peroxide (ClOOCl) equilibrium constant from Aura Microwave Limb Sounder measurements of nighttime ClO.

    Science.gov (United States)

    Santee, Michelle L; Sander, Stanley P; Livesey, Nathaniel J; Froidevaux, Lucien

    2010-04-13

    The primary ozone loss process in the cold polar lower stratosphere hinges on chlorine monoxide (ClO) and one of its dimers, chlorine peroxide (ClOOCl). Recently, analyses of atmospheric observations have suggested that the equilibrium constant, K(eq), governing the balance between ClOOCl formation and thermal decomposition in darkness is lower than that in the current evaluation of kinetics data. Measurements of ClO at night, when ClOOCl is unaffected by photolysis, provide a useful means of testing quantitative understanding of the ClO/ClOOCl relationship. Here we analyze nighttime ClO measurements from the National Aeronautics and Space Administration Aura Microwave Limb Sounder (MLS) to infer an expression for K(eq). Although the observed temperature dependence of the nighttime ClO is in line with the theoretical ClO/ClOOCl equilibrium relationship, none of the previously published expressions for K(eq) consistently produces ClO abundances that match the MLS observations well under all conditions. Employing a standard expression for K(eq), A x exp(B/T), we constrain the parameter A to currently recommended values and estimate B using a nonlinear weighted least squares analysis of nighttime MLS ClO data. ClO measurements at multiple pressure levels throughout the periods of peak chlorine activation in three Arctic and four Antarctic winters are used to estimate B. Our derived B leads to values of K(eq) that are approximately 1.4 times smaller at stratospherically relevant temperatures than currently recommended, consistent with earlier studies. Our results are in better agreement with the newly updated (2009) kinetics evaluation than with the previous (2006) recommendation.

  12. F-band, High-Efficiency GaN Power Amplifier for the Scanning Microwave Limb Sounder and SOFIA Project

    Data.gov (United States)

    National Aeronautics and Space Administration — QuinStar Technology proposes to develop a 4-watt Solid-State Power Amplifier (SSPA) operating at F-band (106-114 GHz) with a power-added efficiency (PAE) of greater...

  13. F-band, High-Efficiency GaN Power Amplifier for the Scanning Microwave Limb Sounder and SOFIA Project

    Data.gov (United States)

    National Aeronautics and Space Administration — QuinStar Technology proposes to develop a high-efficiency, 4-W SSPA operating at F-band frequencies (106-114 GHz). This will be achieved by employing two major...

  14. Technology Development for Cosmic Microwave Background Cosmology

    Science.gov (United States)

    Munson, Charles D.

    2017-05-01

    The Cosmic Microwave Background (CMB) offers a unique window into the early universe by probing thermal radiation remaining from the big bang. Due to its low temperature and bright foregrounds, its thorough characterization requires technological advancement beyond the current state-of-the-art. In this thesis, I present the development and fabrication of novel metamaterial silicon optics to improve the sensitivity of current and future CMB telescopes. By machining subwavelength features into the silicon surfaces, traditional antireflection coatings can be replaced by all-silicon metamaterials that significantly reduce reflections over previous approaches. I discuss the design of these structured surfaces and the design and construction of a sophisticated fabrication facility necessary to implement this technology on large diameter (30+ cm) lenses for the Atacama Cosmology Telescope Polarization project (ACTPol). I then apply this metamaterial technology to the development of improved free-space filters for millimeter and sub-millimeter wavelength imaging (focusing specifically on blocking infrared radiation, necessary for current cryogenic detector systems). This produces a highly effective infrared-blocking filter, blocking over 99% of the incident power from a 300 K blackbody while maintaining transmission of better than 99% in a target CMB observing band (between 70 and 170 GHz). I conclude with a discussion of the development of a real-space simulation framework to assist in better understanding current CMB results and forecasting for future experiments. By taking a CMB realization and adding to it accurate real-space modeling of the Sunyaev-Zel'dovich effect and weak lensing distortions (introduced by galaxy clusters), a better understanding of the impacts of large scale structure on the CMB can be obtained.

  15. NOAA/NESDIS Operational Sounding Processing Systems using the hyperspectral and microwaves sounders data from CrIS/ATMS, IASI/AMSU, and ATOVS

    Science.gov (United States)

    Sharma, A. K.

    2016-12-01

    The current operational polar sounding systems running at the National Oceanic and Atmospheric Administration (NOAA) National Environmental Satellite Data and Information Service (NESDIS) for processing the sounders data from the Cross-track Infrared (CrIS) onboard the Suomi National Polar-orbiting Partnership (SNPP) under the Joint Polar Satellite System (JPSS) program; the Infrared Atmospheric Sounding Interferometer (IASI) onboard Metop-1 and Metop-2 satellites under the program managed by the European Organization for the Exploitation of Meteorological (EUMETSAT); and the Advanced TIROS (Television and Infrared Observation Satellite) Operational Vertical Sounding (ATOVS) onboard NOAA-19 in the NOAA series of Polar Orbiting Environmental Satellites (POES), Metop-1 and Metop-2. In a series of advanced operational sounders CrIS and IASI provide more accurate, detailed temperature and humidity profiles; trace gases such as ozone, nitrous oxide, carbon dioxide, and methane; outgoing longwave radiation; and the cloud cleared radiances (CCR) on a global scale and these products are available to the operational user community. This presentation will highlight the tools developed for the NOAA Unique Combined Atmospheric Processing System (NUCAPS), which will discuss the Environmental Satellites Processing Center (ESPC) system architecture involving sounding data processing and distribution for CrIS, IASI, and ATOVS sounding products. Discussion will also include the improvements made for data quality measurements, granule processing and distribution, and user timeliness requirements envisioned from the next generation of JPSS and GOES-R satellites. There have been significant changes in the operational system due to system upgrades, algorithm updates, and value added data products and services. Innovative tools to better monitor performance and quality assurance of the operational sounder and imager products from the CrIS/ATMS, IASI and ATOVS have been developed and

  16. 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.

  17. Microwave de-/anti-icing using the midas-technology.

    Science.gov (United States)

    Feher, L; Seitz, T; Nuss, V

    2009-01-01

    For aviation, a suitable alternative for currently used in-flight anti-/de-icing technologies for today's aircrafts with metal structures and future aircrafts with replaced composite structures is necessary. Intense investigations performed at FZK have been together in collaboration with aircraft manufacturers to design and develop a new avionic microwave technology for monolithic composite structures.The full system integration has been evaluated for several airplanes considering the structural and efficiency demands. The concept of this MIDAS (MIcrowave De-icing Anti-icing System) technology as well their recent results will be presented. A full system integration has been tested and is visualized in the paper.

  18. New Microwave Technology for Ocean Wind Measurements

    Science.gov (United States)

    Wilson, W. J.; Yueh, S. H.

    1996-01-01

    Global mapping of near surface ocean winds is crucial for many meteorological, oceanographic and atmospheric studies. The microwave emission from the ocean surface is elliptically polarized and the degree of polarizationand angle is a function of the surface wind speed and direction...A summary of all the ocean polarimetric data vs. wind speed and incidence angle from three flights in 1994 and eight flights in 1995 is presented.

  19. 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...

  20. GPM Microwave Imager Key Technologies, Performance and Calibration Results

    OpenAIRE

    Newell, David; Figgins, Don; Draper, David; Berdanier, Barry; Kubitschek, Michael; Holshouser, David; Sexton, Adam; Krimchansky, Sergey; Wentz, Frank; Meissner, Thomas

    2014-01-01

    The Global Precipitation Measurement (GPM) Microwave Imager (GMI) Instrument was built and tested by Ball Aerospace and Technologies Corporation (Ball) under a contract with the GPM program at the National Aeronautics and Space Administration (NASA) Goddard Space Flight Center. The GMI instrument was delivered to Goddard in February 2012 and launched onboard the GPM spacecraft in late February 2014. This paper presents an overview of the GMI instrument, examines pre-flight radiometric accurac...

  1. 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.

  2. Microwave Sensor Technologies for Food Evaluation and Analysis – Methods, Challenges and Solutions

    OpenAIRE

    Meng, Zhaozong; Wu, Zhipeng; Gray, John

    2017-01-01

    Microwave sensor technology is widely accepted as a non-destructive and hygienic means for food evaluation and analysis. However, its applications concentrate on in-lab investigations, which are not widely applied for on-line measurement in food industry. Motivated by the rapid progress of microwave technologies and the lack of on-line measurement systems in industry, this paper aims to provide a comprehensive overview of microwave sensors for food measurement, define the technological gap, a...

  3. Microwave as an emerging technology for the treatment of biohazardous waste: A mini-review.

    Science.gov (United States)

    Zimmermann, Klaus

    2017-05-01

    Microwave is an emerging technology to treat biohazardous waste, including material from healthcare facilities. A screen of the peer-reviewed literature shows that only limited information may be found in this area of work and, furthermore, analysis of the references reveals that sometimes not all necessary aspects for the appropriate use of the technology are considered. Very often conventional microwave technology is applied for the inactivation of pathogens, which might make sense for certain applications but, on the other hand, may lead to the misbelief that microwave systems cannot be used for the inactivation of a solid "dry" waste. However, conventional microwave units have no means to control the inactivation process, and especially moisture content. But there are a few sophisticated microwave technologies with appropriate measurements allowing a validated inactivation of biohazardous materials. These technologies are an effective tool for inactivation and some of them are commercially available. It must also be considered that the waste should be preferably inactivated either directly at the place where it is generated or biohazardous waste should be transported only in closed systems. Moreover, microwave technology presents a possibility to save energy costs in comparison to the more widely used autoclaves. This mini-review will discuss important aspects for the use of microwave technology for the treatment of biohazardous waste.

  4. 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.......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....

  5. microwave satellite water vapour column retrieval for polar winter conditions

    Energy Technology Data Exchange (ETDEWEB)

    Perro, Christopher; Lesins, Glen; Duck, Thomas J.; Cadeddu, Maria

    2016-01-01

    A new microwave satellite water vapour retrieval for the polar winter atmosphere is presented. The retrieval builds on the work of Miao et al. (2001) and Melsheimer and Heygster (2008), employing auxiliary information for atmospheric conditions and numerical optimization. It was tested using simulated and actual measurements from the Microwave Humidity Sounder (MHS) satellite instruments. Ground truth was provided by the G-band vapour radiometer (GVR) at Barrow, Alaska. For water vapour columns less than 6 kg m-2, comparisons between the retrieval and GVR result in a root mean square (RMS) deviation of 0.39 kg m-2 and a systematic bias of 0.08 kg m-2. These results are compared with RMS deviations and biases at Barrow for the retrieval of Melsheimer and Heygster (2008), the AIRS and MIRS satellite data products, and the ERA-Interim, NCEP, JRA-55, and ASR reanalyses. When applied to MHS measurements, the new retrieval produces a smaller RMS deviation and bias than for the earlier retrieval and satellite data products. The RMS deviations for the new retrieval were comparable to those for the ERA-Interim, JRA-55, and ASR reanalyses; however, the MHS retrievals have much finer horizontal resolution (15 km at nadir) and reveal more structure. The new retrieval can be used to obtain pan-Arctic maps of water vapour columns of unprecedented quality. It may also be applied to measurements from the Special Sensor Microwave/Temperature 2 (SSM/T2), Advanced Microwave Sounding Unit B (AMSU-B), Special Sensor Microwave Imager/Sounder (SSMIS), Advanced Technology Microwave Sounder (ATMS), and Chinese MicroWave Humidity Sounder (MWHS) instruments.

  6. Microfabricated Low-Loss Microwave Switch Integration Technology Project

    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...

  7. Microwave Remote Sensing: Needs and Requirements Concerning Technology

    DEFF Research Database (Denmark)

    Skou, Niels

    2003-01-01

    Spaceborne microwave remote sensing instruments, like the imaging radiometer and the synthetic aperture radar, are over timed faced with two partly conflicting requirements: performance expectations (resolutions, sensitivity, coverage) steadily increase with resource allocations (weight, power...

  8. Snowfall Rate Retrieval using NPP ATMS Passive Microwave Measurements

    Science.gov (United States)

    Meng, Huan; Ferraro, Ralph; Kongoli, Cezar; Wang, Nai-Yu; Dong, Jun; Zavodsky, Bradley; Yan, Banghua; Zhao, Limin

    2014-01-01

    Passive microwave measurements at certain high frequencies are sensitive to the scattering effect of snow particles and can be utilized to retrieve snowfall properties. Some of the microwave sensors with snowfall sensitive channels are Advanced Microwave Sounding Unit (AMSU), Microwave Humidity Sounder (MHS) and Advance Technology Microwave Sounder (ATMS). ATMS is the follow-on sensor to AMSU and MHS. Currently, an AMSU and MHS based land snowfall rate (SFR) product is running operationally at NOAA/NESDIS. Based on the AMSU/MHS SFR, an ATMS SFR algorithm has been developed recently. The algorithm performs retrieval in three steps: snowfall detection, retrieval of cloud properties, and estimation of snow particle terminal velocity and snowfall rate. The snowfall detection component utilizes principal component analysis and a logistic regression model. The model employs a combination of temperature and water vapor sounding channels to detect the scattering signal from falling snow and derive the probability of snowfall (Kongoli et al., 2014). In addition, a set of NWP model based filters is also employed to improve the accuracy of snowfall detection. Cloud properties are retrieved using an inversion method with an iteration algorithm and a two-stream radiative transfer model (Yan et al., 2008). A method developed by Heymsfield and Westbrook (2010) is adopted to calculate snow particle terminal velocity. Finally, snowfall rate is computed by numerically solving a complex integral. The ATMS SFR product is validated against radar and gauge snowfall data and shows that the ATMS algorithm outperforms the AMSU/MHS SFR.

  9. Fiber Sensor Systems Based on Fiber Laser and Microwave Photonic Technologies

    Directory of Open Access Journals (Sweden)

    Zhiping Cai

    2012-04-01

    Full Text Available Fiber-optic sensors, especially fiber Bragg grating (FBG sensors are very attractive due to their numerous advantages over traditional sensors, such as light weight, high sensitivity, cost-effectiveness, immunity to electromagnetic interference, ease of multiplexing and so on. Therefore, fiber-optic sensors have been intensively studied during the last several decades. Nowadays, with the development of novel fiber technology, more and more newly invented fiber technologies bring better and superior performance to fiber-optic sensing networks. In this paper, the applications of some advanced photonic technologies including fiber lasers and microwave photonic technologies for fiber sensing applications are reviewed. FBG interrogations based on several kinds of fiber lasers, especially the novel Fourier domain mode locking fiber laser, have been introduced; for the application of microwave photonic technology, examples of microwave photonic filtering utilized as a FBG sensing interrogator and microwave signal generation acting as a transversal loading sensor have been given. Both theoretical analysis and experimental demonstrations have been carried out. The comparison of these advanced photonic technologies for the applications of fiber sensing is carried out and important issues related to the applications have been addressed and the suitable and potential application examples have also been discussed in this paper.

  10. 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.

  11. NASA Activities as they Relate to Microwave Technology for Aerospace Communications Systems

    Science.gov (United States)

    Miranda, Felix A.

    2011-01-01

    This presentation discusses current NASA activities and plans as they relate to microwave technology for aerospace communications. The presentations discusses some examples of the aforementioned technology within the context of the existing and future communications architectures and technology development roadmaps. Examples of the evolution of key technology from idea to deployment are provided as well as the challenges that lay ahead regarding advancing microwave technology to ensure that future NASA missions are not constrained by lack of communication or navigation capabilities. The presentation closes with some examples of emerging ongoing opportunities for establishing collaborative efforts between NASA, Industry, and Academia to encourage the development, demonstration and insertion of communications technology in pertinent aerospace systems.

  12. Next generation global Earth atmospheric composition sounders for the decadal survey requirements and roadmaps Project

    Data.gov (United States)

    National Aeronautics and Space Administration — There are two overall objectives: 1. Define the spatial resolutions and sensitivities required for the instruments; 2. Mature the technology for the limb sounder and...

  13. Color and volatile analysis of peanuts roasted using oven and microwave technologies.

    Science.gov (United States)

    Smith, Alicia L; Barringer, Sheryl A

    2014-10-01

    Roasted peanut color and volatiles were evaluated for different time and temperature combinations of roasting. Raw peanuts were oven roasted at 135 to 204 °C, microwave roasted for 1 to 3 min, or combination roasted by microwave and oven roasting for various times and temperatures. Volatiles were measured using selected ion flow tube mass spectrometry. L* values were used to categorize peanuts as under-roasted, ideally roasted, and over-roasted. The total roasting time in order to achieve ideal color was not shortened by most of the combination treatments compared to their oven roasted equivalents. Oven before microwave roasting compared to the reverse was found to significantly increase the L* value. Peanuts with the same color had different volatile levels. Hexanal concentrations decreased then increased with roasting. Pyrazine levels increased as roasting time increased, although oven at 177 °C treatments had the highest and microwave treatments had the lowest levels. Volatile levels generally increased as roasting time or temperature increased. Oven 177 °C for 15 min generally had the highest level of volatiles among the roasting treatments tested. Soft independent modeling of class analogies based on volatile levels showed that raw peanuts were the most different, commercial samples were the most similar to each other, and oven, microwave, and combination roasting were all similar in volatile profile. Peanuts can be roasted to equivalent colors and have similar volatile levels by different roasting methods. Oven and microwave roasting technologies produced the same roasted peanut color and had similar volatile trends as roasting time increased. Combination roasting also produced ideal color and similar volatile levels indicating that microwave technology could be further explored as a peanut roasting technique. © 2014 Institute of Food Technologists®

  14. 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...

  15. Development of microwave radiometer sensor technology for geostationary earth science platforms

    Science.gov (United States)

    Campbell, T. G.; Lawrence, R. W.; Schroeder, L. C.; Kendall, B. M.; Harrington, R. F.

    1991-01-01

    A new research and technology program has been initiated at the Langley Research Center of the National Aeronautics and Space Administration (NASA) for developing advanced, high resolution microwave radiometer (HI-RES) sensors suitable for Mission to Planet Earth (MPE) remote sensing applications. The objective of this program is to provide the technology needed to enable and enhance the long-term observations, documentation, and understanding of the earth as a system.

  16. 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.

  17. 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

  18. 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.

  19. 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

  20. 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.

  1. 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.

  2. 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

  3. Microwave Irradiation

    Indian Academy of Sciences (India)

    The rapid heating of food in the kitchen using microwave ovens ... analysis; application to waste treatment; polymer technology; .... Microwave heating for carrying out reactions on solids has also attracted considerable attention in recent years. For such 'dry media' reactions, solid supports such as alumina, silica and.

  4. DEVELOPMENT OF ADVANCED DRILL COMPONENTS FOR BHA USING MICROWAVE TECHNOLOGY INCORPORATING CARBIDE, DIAMOND COMPOSITES AND FUNCTIONALLY GRADED MATERIALS

    Energy Technology Data Exchange (ETDEWEB)

    Dinesh Agrawal; Rustum Roy

    2000-11-01

    The main objective of this program was to develop an efficient and economically viable microwave processing technique to process cobalt cemented tungsten carbide with improved properties for drill-bits for advanced drilling operations for oil, gas, geothermal and excavation industries. The program was completed in three years and successfully accomplished all the states goals in the original proposal. In three years of the program, we designed and built several laboratory scale microwave sintering systems for conducting experiments on Tungsten carbide (WC) based composites in controlled atmosphere. The processing conditions were optimized and various properties were measured. The design of the system was then modified to enable it to process large commercial parts of WC/Co and in large quantities. Two high power (3-6 kW) microwave systems of 2.45 GHz were built for multi samples runs in a batch process. Once the process was optimized for best results, the technology was successfully transferred to our industrial partner, Dennis Tool Co. We helped them to built couple of prototype microwave sintering systems for carbide tool manufacturing. It was found that the microwave processed WC/Co tools are not only cost effective but also exhibited much better overall performance than the standard tools. The results of the field tests performed by Dennis Tool Co. showed remarkable advantage and improvement in their overall performance. For example: wear test shows an increase of 20-30%, corrosion test showed much higher resistance to the acid attack, erosion test exhibited about 15% better resistance than standard sinter-HIP parts. This proves the success of microwave technology for WC/Co based drilling tools. While we have successfully transferred the technology to our industrial partner Dennis Tool Co., they have signed an agreement with Valenite, a world leading WC producer of cutting and drilling tools and wear parts, to push aggressively the new microwave technology in

  5. Microwave plasma assisted process for cleaning and deposition in future semiconductor technology

    Science.gov (United States)

    Altmannshofer, S.; Boudaden, J.; Wieland, R.; Eisele, I.; Kutter, C.

    2017-06-01

    The epitaxial growth of silicon layers is an important step in the fabrication of semiconductor devices. For conventional silicon epitaxy, high temperatures, up to 900 °C are necessary. However, in future, semiconductor technology epitaxy processes at lower temperatures are required to increase the integration density. The goal of this study was to investigate microwave plasma assisted processes for the selective removing of thin silicon oxide, the cleaning of silicon surfaces and the depositing of high quality silicon films. The main focus was to apply these processes for low temperature epitaxy. All processes, such as oxide removal, cleaning and deposition, were done in one chamber and with microwave plasma assistance. In order to remove silicon dioxide, the etching behavior of hydrogen, fluorine, and hydrogen/fluorine plasma was studied. It was shown, that with hydrogen/fluorine plasma, the best selectivity of oxide to silicon was reached. The deposition process of silicon was studied by growing μc-Si films. The process was characterized and optimized by spectral ellipsometry. After a successful characterization of all process steps, silicon epitaxy layers have been grown with in-situ removal of native oxide and in-situ surface cleaning. The temperature for all process steps was reduced below 450 °C.

  6. Microwave photonics

    CERN Document Server

    Lee, Chi H

    2013-01-01

    Microwave photonics continues to see rapid growth. The integration of optical fiber and wireless networks has become a commercial reality and is becoming increasingly pervasive. Such hybrid technology will lead to many innovative applications, including backhaul solutions for mobile networks and ultrabroadband wireless networks that can provide users with very high bandwidth services. Microwave Photonics, Second Edition systematically introduces important technologies and applications in this emerging field. It also reviews recent advances in micro- and millimeter-wavelength and terahertz-freq

  7. 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

  8. Progress in GaAs Metamorphic HEMT Technology for Microwave Applications. High Efficiency Ka-Band MHEMT Power MMICs

    Science.gov (United States)

    Smith, P. M.; Dugas, D.; Chu, K.; Nichols, K.; Duh, K. H.; Fisher, J.; MtPleasant, L.; Xu, D.; Gunter, L.; Vera, A.

    2003-01-01

    This paper reviews recent progress in the development of GaAs metamorphic HEMT (MHEMT) technology for microwave applications. Commercialization has begun, while efforts to further improve performance, manufacturability and reliability continue. We also report the first multi-watt MHEMT MMIC power amplifiers, demonstrating up to 3.2W output power and record power-added efficiency (PAE) at Ka-band.

  9. Nanowires and sidewall Bragg gratings in silicon as enabling technologies for microwave photonic filters.

    Science.gov (United States)

    Chen, Lawrence R; Li, Jia; Spasojevic, Mina; Adams, Rhys

    2013-08-26

    We describe the use of various silicon photonic device technologies to implement microwave photonic filters (MPFs). We demonstrate four-wave mixing in a silicon nanowire waveguide (SNW) to increase the number of taps for MPFs based on finite impulse response filter designs. Using a 12 mm long SNW reduces the footprint by five orders of magnitude compared to silica highly nonlinear fiber while only requiring approximately two times more input power. We also demonstrate optical delays based on serial sidewall Bragg grating arrays and step-chirped sidewall Bragg gratings in silicon waveguides. We obtain up to 63 ps delay in discrete steps from 15 ps to 32 ps over a wide bandwidth range from 33 nm to at least 62 nm. These components can be integrated with other silicon-based components such as integrated spectral shapers and modulators to realize a fully integrated MPF.

  10. 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.

  11. 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.

  12. A comparative study of in-gel digestions using microwave and pressure-accelerated technologies.

    Science.gov (United States)

    Alvarado, Rudy; Tran, Diana; Ching, Bonnie; Phinney, Brett S

    2010-09-01

    One of the most popular methods to prepare tryptic peptides for bottom-up proteomic analysis is in-gel digestion. To date, there have been few studies comparing various digestion methods. In this study, we compare the efficiency of several popular in-gel digestion methods, along with new technologies that may improve digestion efficiency, using a human epidermoid carcinoma cell lysate protein standard. The efficiency of each protocol was based on the average number of proteins identified and their respective sequence coverage and relative quantitation using spectral counting. The importance of this study lies in its comparison of pre-existing in-gel digestion methods with those that use newly developed technologies that may introduce the potential for a more cost-effective digestion, higher protein yield, and an overall reduction in processing time. The following four protocols were compared: an overnight in-gel digestion protocol; an overnight in-gel digestion protocol, in which we remove the vacuum centrifugation steps; in-gel digestion in a barometric pressure cycler; and in-gel digestion in a scientific microwave. Several variables were tested for increased digestion efficiency and decreased keratin contamination. Statistical analysis was performed on replicate samples to determine significant differences between protocols.

  13. The Mars express MARSIS sounder instrument

    Science.gov (United States)

    Jordan, R.; Picardi, G.; Plaut, J.; Wheeler, K.; Kirchner, D.; Safaeinili, A.; Johnson, W.; Seu, R.; Calabrese, D.; Zampolini, E.; Cicchetti, A.; Huff, R.; Gurnett, D.; Ivanov, A.; Kofman, W.; Orosei, R.; Thompson, T.; Edenhofer, P.; Bombaci, O.

    2009-12-01

    The Mars advanced radar for subsurface and ionospheric sounding (MARSIS) on Mars Express is the first high-frequency sounding radar operating from orbital altitudes since the Apollo 17 Lunar Sounder flown in 1972. The radar operates from a highly elliptical orbit but acquires data only from altitudes lower than 1200 km. The periapsis altitude is 250 km. This radar has been succesfully operating since August 2005. The radar is a dual channel low-frequency sounder, operates between 1.3 and 5.5 MHz (MegaHertz) with wavelengths between 230 and 55 m in free space for subsurface sounding and between 0.1 and 5.5 MHz (wavelengths between 3000 and 55 m) for ionospheric sounding. The subsurface sounder can operate at one or two-frequency bands out of four available bands at either like or cross polarization. The subsurface sounding radar transmits radio frequency (RF) pulses of 250 μs duration through a 40 m dipole antenna. The return echoes are then converted to digital form and temporarily stored on board for some digital processing. A second antenna, a monopole, provides reception for the cross-polarized return and its data are processed by a second channel. This processing reduces the data rate produced by the instrument to rates allowed by the spacecraft communications channel. These processed returns are then sent to Earth by the telecommunications system on the spacecraft. The advances in digital data acquisition and processing, since 1972, have enabled this technique to be used in a compact spacecraft science instrument.. This sounder has obtained returns from several kilometers below the surface of the Mars. The ionospheric sounder operates at altitudes greater than 800 km in a mode that sweeps the entire 0.1-5.5 MHz range. During ionospheric sounding, the transmitter sends a 91 μs tone at 127 pulses per second rate. The frequency sweep takes 7.3 s to complete the 0.1-5.5 MHz range. Operational aspects of the instrument are described, including the selection of

  14. Characterizations of microwave plasma CVD grown polycrystalline diamond coatings for advanced technological applications

    Directory of Open Access Journals (Sweden)

    Awadesh Kumar Mallik

    2014-06-01

    Full Text Available Polycrystalline diamond (PCD coatings ranging from few microns to several hundred microns thickness have been grown by 915 MHz microwave plasma reactor with 9000 W power. The coatings were deposited on 100 mm diameter silicon (Si substrate from few hours to several days of continuous runs. PCD coatings were made freestanding by wet chemical etching technique. The deposited PCDs were evaluated by X-ray diffraction (XRD, scanning electron microscopy (SEM, Raman spectroscopy, X-ray photoelectron spectroscopy (XPS for physical characterization and compared with authors’ earlier work. Refractive index of 2.41 was obtained at 633 nm wavelength and a maximum of 6.6 W·cm-1K-1 value for thermal conductivity could be achieved with the grown coatings. The values are well above the existing non-diamond heat spreading substrates, which makes the grown PCDs as candidates for heat spreaders in different technological applications. High refractive index along with translucent nature of the white freestanding PCDs, make them potential candidate for optical windows.

  15. Errors from Rayleigh-Jeans approximation in satellite microwave radiometer calibration systems.

    Science.gov (United States)

    Weng, Fuzhong; Zou, Xiaolei

    2013-01-20

    The advanced technology microwave sounder (ATMS) onboard the Suomi National Polar-orbiting Partnership (SNPP) satellite is a total power radiometer and scans across the track within a range of ±52.77° from nadir. It has 22 channels and measures the microwave radiation at either quasi-vertical or quasi-horizontal polarization from the Earth's atmosphere. The ATMS sensor data record algorithm employed a commonly used two-point calibration equation that derives the earth-view brightness temperature directly from the counts and temperatures of warm target and cold space, and the earth-scene count. This equation is only valid under Rayleigh-Jeans (RJ) approximation. Impacts of RJ approximation on ATMS calibration biases are evaluated in this study. It is shown that the RJ approximation used in ATMS radiometric calibration results in errors on the order of 1-2 K. The error is also scene count dependent and increases with frequency.

  16. Effect and mechanism of microwave-activated ultraviolet-advanced oxidation technology for adsorbent regeneration.

    Science.gov (United States)

    Sun, Yanlong; Zheng, Tong; Zhang, Guangshan; Zheng, Yunli; Wang, Peng

    2017-10-15

    To decrease the secondary pollution of volatile organic compounds (VOCs) during adsorbent regeneration by microwave, electrodeless lamp was added in the microwave field to oxidize VOCs in the gas phase. Ultraviolet has a significant improvement on mineralization of VOCs generated from adsorbate during adsorbent regeneration. However, the mechanism and main influence factors on the degradation of VOCs are not clear. The effect of microwave power, regeneration time, airflow rate, and humidity content on the mineralization of adsorbed tetracycline during adsorbent regeneration was studied. Ozone concentration and ultraviolet irradiation intensity were also measured to analyze the mechanism of the microwave-ultraviolet adsorbent regeneration method. Although the electrodeless lamp adsorbed microwave and competed with the regenerated adsorbent, the mineralization percentage of tetracycline increased about 10% with the presence of electrodeless lamp at the same microwave power supply. Besides, humidity content also takes an important role on enhancing the mineralization of tetracycline. The mineralization of tetracycline in the microwave-ultraviolet field consists of three major parts: pyrolysis, ozone oxidation, and free radical oxidation. More than 50% adsorbed tetracycline can be oxidized into H2O and CO2 during regeneration in 5 min. These results support the potential use of electrodeless lamp to treat VOCs in the gas phase to decrease the risk of secondary pollution during adsorbent regeneration.

  17. 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 ...

  18. Technological, chemical, sensory, and microbiological examination of frozen chicken as affected by microwave thawing

    OpenAIRE

    Kenawi M.A.

    2005-01-01

    The effect of microwave heating as a thawing method on physical, chemical sensory, and microbiological properties of frozen chicken was investigated in comparison with other thawing methods (at ambient temperature, in refrigerator, and in running tap water). Microwave thawed chicken had the highest taste panel scores and the lowest drip percentage loss compared with the other thawing methods. Thiobarbituric acid value (TBA) remarkably increased the samples thawed at ambient temperature or und...

  19. Medical applications of microwaves

    Science.gov (United States)

    Vrba, Jan; Lapes, M.

    2004-04-01

    Medical applications of microwaves (i.e. a possibility to use microwave energy and/or microwave technique and technology for therapeutical purposes) are a quite new and a very rapidly developing field. Microwave thermotherapy is being used in medicine for the cancer treatment and treatment of some other diseases since early eighties. In this contribution we would like to offer general overview of present activities in the Czech Republic, i.e. clinical applications and results, technical aspects of thermo therapeutic equipment and last but not least, prospective diagnostics based on microwave principals ant technology and instrumentation.

  20. An FPGA-Based Adaptable 200 MHz Bandwidth Channel Sounder for Wireless Communication Channel Characterisation

    Directory of Open Access Journals (Sweden)

    David L. Ndzi

    2011-01-01

    Full Text Available This paper describes the development of a fast adaptable FPGA-based wideband channel sounder with signal bandwidths of up to 200 MHz and channel sampling rates up to 5.4 kHz. The application of FPGA allows the user to vary the number of real-time channel response averages, channel sampling interval, and duration of measurement. The waveform, bandwidth, and frequency resolution of the sounder can be adapted for any channel under investigation. The design approach and technology used has led to a reduction in size and weight by more than 60%. This makes the sounder ideal for mobile time-variant wireless communication channels studies. Averaging allows processing gains of up to 30 dB to be achieved for measurement in weak signal conditions. The technique applied also improves reliability, reduces power consumption, and has shifted sounder design complexity from hardware to software. Test results show that the sounder can detect very small-scale variations in channels.

  1. Millimeter-Wave Atmospheric Sounder (MAS)

    Science.gov (United States)

    Hartmann, G. K.

    1988-01-01

    MAS is a remote sensing instrument for passive sounding (limb sounding) of the earth's atmosphere from the Space Shuttle. The main objective of the MAS is to study the composition and dynamic structure of the stratosphere, mesosphere, and lower thermosphere in the height range 20 to 100 km, the region known as the middle atmosphere. The MAS will be flown on the Atmospheric Laboratory for Applications and Science (ATLAS 1) NASA mission scheduled for late 1990. The Millimeter-Wave Atmospheric Sounder will provide, for the first time, information obtained simultaneously on the temperature and on ozone concentrations in the 20 to 90 km altitude region. The information will cover a large area of the globe, will have high accuracy and high vertical resolution, and will cover both day and night times. Additionally, data on the two important molecules, H2O and ClO, will also be provided.

  2. 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.

  3. Microwaving human faecal sludge as a viable sanitation technology option for treatment and value recovery - A critical review.

    Science.gov (United States)

    Afolabi, Oluwasola O D; Sohail, M

    2017-02-01

    The prolonged challenges and terrible consequences of poor sanitation, especially in developing economies, call for the exploration of new sustainable sanitation technologies. Such technologies must be: capable of effectively treating human faecal wastes without any health or environmental impacts; scalable to address rapid increases in population and urbanization; capable of meeting environmental regulations and standards for faecal management; and competitive with existing strategies. Further and importantly, despite its noxiousness and pathogenic load, the chemical composition of human faecal sludge indicates that it could be considered a potentially valuable, nutrient-rich renewable resource, rather than a problematic waste product. New approaches to faecal sludge management must consequently seek to incorporate a 'valuable resource recovery' approach, compatible with stringent treatment requirements. This review intends to advance the understanding of human faecal sludge as a sustainable organic-rich resource that is typically high in moisture (up to 97 per cent), making it a suitable candidate for dielectric heating, i.e. microwave irradiation, to promote faecal treatment, while also recovering value-added products such as ammonia liquor concentrate (suitable for fertilizers) and chars (suitable for fuel) - which can provide an economic base to sustain the technology. Additionally, microwaving human faecal sludge represents a thermally effective approach that can destroy pathogens, eradicate the foul odour associated human faecal sludge, while also preventing hazardous product formations and/or emissions, aside from other benefits such as improved dewaterability and heavy metals recovery. Key technological parameters crucial for scaling the technology as a complementary solution to the challenges of onsite sanitation are also discussed. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. [New technology for linear colliders

    Energy Technology Data Exchange (ETDEWEB)

    McIntyre, P.M.

    1992-08-12

    This report discusses the following topics on research of microwave amplifiers for linear colliders: Context in current microwave technology development; gated field emission for microwave cathodes; cathode fabrication and tests; microwave cathode design using field emitters; and microwave localization.

  5. GRIPS - The Geostationary Remote Infrared Pollution Sounder

    Science.gov (United States)

    Spackman, Ryan; Dickerson, Russell; Schoeberl, Mark; Bloom, Hal; Gordley, Larry; McHugh, Martin; Thompson, Anne; Burrows, John; Zeng, Ning; Marshall, Tom; Fish, Chad; Kim, Jhoon; Park, Rokjin; Warner, Juying; Bhartia, Pawan; Kollonige, Debra

    2013-04-01

    Climate change and air quality are the most pressing environmental issues of the 21st century for America and for the world as a whole. Despite decades of research, the sources and sinks of key greenhouse gases and other pollutants remain highly uncertain making atmospheric composition predictions difficult. The Geostationary Remote Infrared Pollution Sounder (GRIPS) will measure carbon dioxide (CO2), carbon monoxide (CO), and methane (CH4). By using measurements of nitrous oxide (N2O) and the O2 A-band to help correct for clouds and aerosols, GRIPS will achieve unprecedented precision. Together these gases account for about 85% of all climate forcing and they impact atmospheric ozone (O3). GRIPS, employing gas-filter correlation radiometry, uses the target gases themselves in place of dispersive elements to achieve outstanding throughput, sensitivity, and specificity. Because it uses a combination of reflected and thermal IR, GRIPS will detect trace gas concentrations right down to the Earth's surface. When flown in parallel to a UV/VIS sensor such as GEMS on GEO-KOMPSAT-2B over East Asia or the Sentinel 4 on MTG over Europe/Africa, the combination offers powerful finger-printing capabilities to distinguish and quantify diverse pollution sources such as electricity generation, biomass burning, and motor vehicles. From geostationary orbit, GRIPS will be able to focus on important targets to quantify sources, net flux, diurnal cycles, and long-range transport of these key components in the Earth's radiative balance and air quality.

  6. 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.

  7. MTG infrared sounder detection chain: first radiometric test results

    Science.gov (United States)

    Dumestier, D.; Pistone, F.; Dartois, T.; Blazquez, E.

    2017-11-01

    Europe's next fleet of geostationary meteorological satellites, MeteoSat Third Generation, will introduce new functions in addition to continuity of high-resolution meteorological data. The atmosphere Infrared Sounder (IRS), as high -end instrument, is part of this challenging program. IRS principle is a Fourier Transform Interferometer, which allows recomposing atmospheric spectrum after infrared photons detection. Transmission spectrums will be used to support numerical weather prediction. IRS instrument is able to offer full disk coverage in one hour, an on-ground resolution of 4 by 4 km, in two spectral bands (MWIR: 1600 to 2175cm-1 and LWIR: 700 to 1210cm-1) with a spectral resolution of 0.6cm-1. Among critical technologies and processes, IRS detection chain shall offer outstanding characteristics in terms of radiometric performance like Signal to Noise Ratio (SNR), dynamic range and linearity. Selected detectors are HgCdTe two-dimensions arrays, cooled at 55 Kelvins, hybridized on snapshot silicon read-out circuit at 160x160 format. Video electronics present 16 bits resolution, and the whole detection chain (Detectors and electronics) permits to reach SNR between 2 000 and 10 000 as requested by the application. Radiometric onground test results performed on design representative detection chains are presented and are confirming the challenging phase A design choices.

  8. 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

  9. 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

  10. On-orbit radiometric validation and field-of-view calibration of spaceborne microwave sounding instruments

    Science.gov (United States)

    Blackwell, William J.; Bickmeier, Laura J.; Jairam, Laura G.; Leslie, R. Vincent

    2008-12-01

    Two calibration/validation efforts planned for current and future spaceborne microwave sounding instruments will be presented. First, the NPOESS Aircraft Sounder Testbed-Microwave (NAST-M) airborne sensor is used to directly validate the microwave radiometers (AMSU and MHS) on several operational satellites. Comparison results for underflights of the Aqua, NOAA, and MetOp-A satellites will be shown. Second, a potential approach will be presented for on-orbit field-of-view (FOV) calibration of the Advanced Technology Microwave Sounder (ATMS). A variety of proposed spacecraft maneuvers that could facilitate the characterization of the radiometric boresight of all 22 ATMS channels will be discussed. Radiance observations from the NAST-M airborne sensor can be used to directly validate the radiometric performance of spaceborne sensors. NAST-M includes a total of four spectrometers, with three operating near the oxygen lines at 50-57, 118.75, and 424.76 GHz, and a fourth spectrometer centered on the water vapor absorption line at 183.31 GHz. All four feedhorns are co-located, have 3-dB (full-width at half-maximum) beamwidths of 7.5° (translating to 2.5-km nominal pixel diameter at nadir incidence), and are directed at a single mirror that scans cross-track beneath the aircraft with a nominal swath width of 100 km. We will present results for two recent validation efforts: 1) the Pacific THORpex (THe Observing-system Research and predictability experiment) Observing System Test (PTOST 2003, Honolulu, HI) and 2) the Joint Airborne IASI Validation Experiment (JAIVEx 2007, Houston, TX). Radiance differences between the NAST-M sensor and the Advanced Microwave Sounding Unit (AMSU) and the Microwave Humidity Sensor (MHS) were found to be less than 1K for most channels. Comparison results for ocean underflights of the Aqua, NOAA, and MetOp-A satellites are shown. We also present an approach for on-orbit FOV calibration of the ATMS satellite instrument using vicarious

  11. 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.

  12. 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

  13. Probing Mars’ atmosphere with ExoMars Mars Climate Sounder

    OpenAIRE

    Irwin, Patrick G. J.; Calcutt, S. B.; Read, P. L.; Bowles, N. E.; Lewis, S.

    2011-01-01

    The 2016 Mars Trace Gas Mission will carry with it the ExoMars Mars Climate Sounder instrument, a development of the very successful Mars Climate Sounder instrument already in orbit about Mars on NASA's Mars Reconnaissance Orbiter spacecraft. EMCS will continue the monitoring of Mars global temperature/pressure/aerosol field, and will also be able to measure the vertical profile of water vapour across the planet from 0 – 50 km. Key components of EMCS will be provided by Oxford, Reading and Ca...

  14. Precision Membrane Optical Shell (PMOS) Technology for RF/Microwave to Lightweight LIDAR Apertures Project

    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...

  15. Design and testing of hardware improvements of an acoustic sounder

    Science.gov (United States)

    Richards, W. L.

    1985-06-01

    The application of lasers in military communications and weapons systems accentuate the need for instruments capable of measuring the fine dynamic structure of the atmosphere. One of the most useful tools available for the probing of the atmosphere is the acoustic sounder. Commercial grade acoustic sounders, such as the Aeroviroment model number 300 cannot collect atmospheric data with the quality needed for laser propagation research. The usable range of the Aerovironment model 300 acoustic sounder is less than 500 meters. Many laser systems need atmospheric information at altitudes of 1 to 2 kilometers and higher. The objective of this thesis was to upgrade an existing acoustic sounder to increase the range and improve the quality of the receiver-processor. A serious deficiency of the Aerovironment model number 300 is the poor coupling of the acoustic transducer to the feedhorn. This thesis involved a complete redesign and experimental test of the transducer feedhorn using two different horn styles as well as making the horn removable and easily changeable.

  16. Mean grain size mapping with single-beam echo sounders

    NARCIS (Netherlands)

    Walree, P.A. van; Ainslie, M.A.; Simons, D.G.

    2006-01-01

    Echo energies of single-beam echo sounders are inverted for the sediment mean grain size via a combination of theoretical and empirical relationships. In situ measurements of the seafloor mass density have revealed the presence of a thin transition layer between the water and the sediment. Within

  17. The JPSS CrIS Instrument and the Evolution of Space-Based Infrared Sounders

    Science.gov (United States)

    Glumb, Ronald; Suwinski, Lawrence; Wells, Steven; Glumb, Anna; Malloy, Rebecca; Colton, Marie

    2018-01-01

    This paper will summarize the development of infrared sounders since the 1970s, describe the technological hurdles that were overcome to provide ever-increasing performance capabilities, and highlight the radiometric performance of the CrIS instrument on JPSS-1 (CrIS-JPSS1). This includes details of the CrIS-JPSS1 measured noise-equivalent spectral radiance (NEdN) performance, radiometric uncertainty performance utilizing a new and improved internal calibration target, short-term and long-term repeatability, spectral uncertainty, and spectral stability. In addition, the full-resolution operating modes for CrIS-JPSS1 will be reviewed, including a discussion of how these modes will be used during on-orbit characterization tests. We will provide a brief update of CrIS-SNPP on-obit performance and the production status of the CrIS instruments for JPSS-2 through JPSS-4. Current technological challenges will also be reviewed, including how ongoing research and development is enabling improvements to future sounders. The expanding usage of infrared sounding data will also be discussed, including demonstration of value via data assimilation, the roles of the public/private sector in communicating the importance of sounding data for long-term observations, and the long road to success from research to operational data products.

  18. Acoustical surveys of Methane plumes using the quantitative echo sounder in Japan Sea 2008

    Science.gov (United States)

    Aoyama, C.; Matsumoto, R.

    2008-12-01

    The research and training vessel Umitaka-maru (Tokyo Univ. of Marine Science and Technology) and the research vessel Natsushima (JAMSTEC) sailed to the methane seep area on a small ridge in the Naoetsu Basin, in the eastern margin of the Sea of Japan in 2004 to 2008 to survey the ocean floor methane hydrates and related acoustic signatures of methane plumes by using a quantitative echo sounder. We mapped minute details of active methane plumes by using a quantitative echo sounder with positioning data from GPS. We also measured average of echo intensity from the methane plumes and sea bottom features both over every 1m range and every 4 seconds employing the echo integrator. We took a still picture and filmed the methane seep area. We obtained the following results from the present echo sounder survey and the experiment in situ. 1) The floating up speed of the methane hydrate bubbles was 600m an hour without depending on the amount of methane hydrates. 2) The backscattering strength of methane hydrate bubbles, whose volume is known, was calculated, and calibration was conducted. 3) We clarified that the methane hydrate bubbles were floating up intermittently. Based on the results, this acoustical method is an effective approach to record the behaviors of the methane hydrate in the water column and to monitor the course of methane hydrate bubbles floating up to the surface. As a following up project, we are planning to make a trial calculation of the amount of floating methane bubbles and methane hydrates using the result of acoustic calibration.

  19. 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

  20. A Comparative Study of In-Gel Digestions Using Microwave and Pressure-Accelerated Technologies

    OpenAIRE

    Alvarado, Rudy; Tran, Diana; Ching, Bonnie; Phinney, Brett S.

    2010-01-01

    One of the most popular methods to prepare tryptic peptides for bottom-up proteomic analysis is in-gel digestion. To date, there have been few studies comparing various digestion methods. In this study, we compare the efficiency of several popular in-gel digestion methods, along with new technologies that may improve digestion efficiency, using a human epidermoid carcinoma cell lysate protein standard. The efficiency of each protocol was based on the average number of proteins identified and ...

  1. Snowfall Rate Retrieval Using Passive Microwave Measurements and Its Applications in Weather Forecast and Hydrology

    Science.gov (United States)

    Meng, Huan; Ferraro, Ralph; Kongoli, Cezar; Yan, Banghua; Zavodsky, Bradley; Zhao, Limin; Dong, Jun; Wang, Nai-Yu

    2015-01-01

    (AMSU), Microwave Humidity Sounder (MHS) and Advance Technology Microwave Sounder (ATMS). ATMS is the follow-on sensor to AMSU and MHS. Currently, an AMSU and MHS based land snowfall rate (SFR) product is running operationally at NOAA/NESDIS. Based on the AMSU/MHS SFR, an ATMS SFR algorithm has also been developed. The algorithm performs retrieval in three steps: snowfall detection, retrieval of cloud properties, and estimation of snow particle terminal velocity and snowfall rate. The snowfall detection component utilizes principal component analysis and a logistic regression model. It employs a combination of temperature and water vapor sounding channels to detect the scattering signal from falling snow and derives the probability of snowfall. Cloud properties are retrieved using an inversion method with an iteration algorithm and a two-stream radiative transfer model. A method adopted to calculate snow particle terminal velocity. Finally, snowfall rate is computed by numerically solving a complex integral. The SFR products are being used mainly in two communities: hydrology and weather forecast. Global blended precipitation products traditionally do not include snowfall derived from satellites because such products were not available operationally in the past. The ATMS and AMSU/MHS SFR now provide the winter precipitation information for these blended precipitation products. Weather forecasters mainly rely on radar and station observations for snowfall forecast. The SFR products can fill in gaps where no conventional snowfall data are available to forecasters. The products can also be used to confirm radar and gauge snowfall data and increase forecasters' confidence in their prediction.

  2. Development of Breakthrough Technology for Spaceflight Microwave Radiometers? RFI Noise Detection and Mitigation Based on the HHT2 Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Microwave active/passive radiometer is the premier instrument for remote sensing of Earth. However, it carries the price of non-linear response by its horn-receiver...

  3. Applications and Lessons Learned using Data from the Atmospheric Infrared Sounder

    Science.gov (United States)

    Ray, S. E.; Fetzer, E. J.; Olsen, E. T.; Lambrigtsen, B.; Pagano, T. S.; Teixeira, J.; Licata, S. J.; Hall, J. R.

    2016-12-01

    Applications and Lessons Learned using Data from the Atmospheric Infrared SounderSharon Ray, Jet Propulsion Laboratory, California Institute of Technology The Atmospheric Infrared Sounder (AIRS) on NASA's Aqua spacecraft has been returning daily global observations of Earth's atmospheric constituents and properties since 2002. With a 12-year data record and daily, global observations in near real-time, AIRS can play a role in applications that fall under many of the NASA Applied Sciences focus areas. AIRS' involvement in applications is two years in, so what have we learned and what are the pitfalls? AIRS has made gains in drought applications with products under consideration for inclusion in the U.S. Drought Monitor national map, as also with volcano rapid response with an internal alert system and automated products to help characterize plume extent. Efforts are underway with cold air aloft for aviation, influenza outbreak prediction, and vector borne disease. But challenges have occurred both in validation and in crossing the "valley of death" between products and decision makers. AIRS now has improved maps of standard products to be distributed in near real-time via NASA LANCE and by the Goddard DAAC as part of the Obama's administration Big Earth Data Initiative. In addition internal tools have been developed to support development and distribution of our application products. This talk will communicate the status of the AIRS applications effort along with lessons learned, and provide examples of new product imagery designed to best communicate AIRS data.

  4. Interpreting Observations of Large-Scale Traveling Ionospheric Disturbances by Ionospheric Sounders

    Science.gov (United States)

    Pederick, L. H.; Cervera, M. A.; Harris, T. J.

    2017-12-01

    From July to October 2015, the Australian Defence Science and Technology Group conducted an experiment during which a vertical incidence sounder (VIS) was set up at Alice Springs Airport. During September 2015 this VIS observed the passage of many large-scale traveling ionospheric disturbances (TIDs). By plotting the measured virtual heights across multiple frequencies as a function of time, the passage of the TID can be clearly displayed. Using this plotting method, we show that all the TIDs observed during the campaign by the VIS at Alice Springs show an apparent downward phase progression of the crests and troughs. The passage of the TID can be more clearly interpreted by plotting the true height of iso-ionic contours across multiple plasma frequencies; the true heights can be obtained by inverting each ionogram to obtain an electron density profile. These plots can be used to measure the vertical phase speed of a TID and also reveal a time lag between events seen in true height compared to virtual height. To the best of our knowledge, this style of analysis has not previously been applied to other swept-frequency sounder observations. We develop a simple model to investigate the effect of the passage of a large-scale TID on a VIS. The model confirms that for a TID with a downward vertical phase progression, the crests and troughs will appear earlier in virtual height than in true height and will have a smaller apparent speed in true height than in virtual height.

  5. Hurricane Alex as Observed by NASA's Spaceborne Atmospheric Infrared Sounder (AIRS)

    Science.gov (United States)

    2004-01-01

    6 mph. [figure removed for brevity, see original site] August 1, 2004, 1:30am ET Daylight snapshot from AIRS visible/near-infrared. At the time AIRS made this observation, Alex was still a tropical depression and just getting organized. Movies Slice down the atmosphere with the AIRS infrared sensor. [figure removed for brevity, see original site] August 3, 2004, 1:30am ET Alex becomes the first hurricane of the 2004 North Atlantic season with sustained winds at 75 mph. [figure removed for brevity, see original site] August 2, 2004, 1:30pm ET Alex is located about 120 miles southeast of Charleston, South Carolina. Alex has now begun to move to the northeast and a general northeastward track is expected the next couple of days with a gradual acceleration in forward speed as it begins to interact with stronger upper level winds. [figure removed for brevity, see original site] August 2, 2004, 1:30am ET Alex now has sustained winds of 35 knots. [figure removed for brevity, see original site] August 1, 2004, 1:30pm ET Alex is tropical depression and beginning to get organized. The Atmospheric Infrared Sounder Experiment, with its visible, infrared, and microwave detectors, provides a three-dimensional look at Earth's weather. Working in tandem, the three instruments can make simultaneous observations all the way down to the Earth's surface, even in the presence of heavy clouds. With more than 2,000 channels sensing different regions of the atmosphere, the system creates a global, 3-D map of atmospheric temperature and humidity and provides information on clouds, greenhouse gases, and many other atmospheric phenomena. The AIRS Infrared Sounder Experiment flies onboard NASA's Aqua spacecraft and is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., under contract to NASA. JPL is a division of the California Institute of Technology in Pasadena.

  6. Community Radiative Transfer Model Applications - A Study of the Retrieval of Trace Gases in the Atmosphere from Cross-track Infrared Sounder (CrIS) Data of a Full-spectral Resolution

    Science.gov (United States)

    Liu, Q.; Nalli, N. R.; Tan, C.; Zhang, K.; Iturbide, F.; Wilson, M.; Zhou, L.

    2015-12-01

    The Community Radiative Transfer Model (CRTM) [3] operationally supports satellite radiance assimilation for weather forecasting, sensor data verification, and the retrievals of satellite products. The CRTM has been applied to UV and visible sensors, infrared and microwave sensors. The paper will demonstrate the applications of the CRTM, in particular radiative transfer in the retrieva algorithm. The NOAA Unique CrIS/ATMS Processing System (NUCAPS) operationally generates vertical profiles of atmospheric temperature (AVTP) and moisture (AVMP) from Suomi NPP Cross-track Infrared Sounder (CrIS) and Advanced Technology Microwave Sounder (ATMS) measurements. Current operational CrIS data have reduced spectral resolution: 1.25 cm-1 for a middle wave band and 2.5 cm-1 for a short-wave wave band [1]. The reduced spectral data largely degraded the retrieval accuracy of trace gases. CrIS full spectral data are also available now which have single spectral resolution of 0.625 cm-1 for all of the three bands: long-wave band, middle wave band, and short-wave band. The CrIS full-spectral resolution data is critical to the retrieval of trace gases such as O3, CO [2], CO2, and CH4. In this paper, we use the Community Radiative Transfer Model (CRTM) to study the impact of the CrIS spectral resolution on the retrieval accuracy of trace gases. The newly released CRTM version 2.2.1 can simulates Hamming-apodized CrIS radiance of a full-spectral resolution. We developed a small utility that can convert the CRTM simulated radiance to un-apodized radiance. The latter has better spectral information which can be helpful to the retrievals of the trace gases. The retrievals will be validated using both NWP model data as well as the data collected during AEROSE expeditions [4]. We will also discuss the sensitivity on trace gases between apodized and un-apodized radiances. References[1] Gambacorta, A., et al.(2013), IEEE Lett., 11(9), doi:10.1109/LGRS.2014.230364, 1639-1643. [2] Han, Y., et

  7. Satellite Sounder Data Assimilation for Improving Alaska Region Weather Forecast

    Science.gov (United States)

    Zhu, Jiang; Stevens, E.; Zhang, X.; Zavodsky, B. T.; Heinrichs, T.; Broderson, D.

    2014-01-01

    A case study and monthly statistical analysis using sounder data assimilation to improve the Alaska regional weather forecast model are presented. Weather forecast in Alaska faces challenges as well as opportunities. Alaska has a large land with multiple types of topography and coastal area. Weather forecast models must be finely tuned in order to accurately predict weather in Alaska. Being in the high-latitudes provides Alaska greater coverage of polar orbiting satellites for integration into forecasting models than the lower 48. Forecasting marine low stratus clouds is critical to the Alaska aviation and oil industry and is the current focus of the case study. NASA AIRS/CrIS sounder profiles data are used to do data assimilation for the Alaska regional weather forecast model to improve Arctic marine stratus clouds forecast. Choosing physical options for the WRF model is discussed. Preprocess of AIRS/CrIS sounder data for data assimilation is described. Local observation data, satellite data, and global data assimilation data are used to verify and/or evaluate the forecast results by the MET tools Model Evaluation Tools (MET).

  8. Microwave-Assisted Olefin Metathesis

    Science.gov (United States)

    Nicks, François; Borguet, Yannick; Sauvage, Xavier; Bicchielli, Dario; Delfosse, Sébastien; Delaude, Lionel; Demonceau, Albert

    Since the first reports on the use of microwave irradiation to accelerate organic chemical transformations, a plethora of papers have been published in this field. In most examples, microwave heating has been shown to dramatically reduce reaction times, increase product yields, and enhance product purity by reducing unwanted side reactions compared to conventional heating methods. The present contribution aims at illustrating the advantages of this technology in olefin metathesis and, when data are available, at comparing microwave-heated and conventionally heated experiments

  9. Rapid hydrolysis of proteins and peptides by means of microwave technology and its application to amino acid analysis.

    Science.gov (United States)

    Chen, S T; Chiou, S H; Chu, Y H; Wang, K T

    1987-10-01

    A rapid heating method of hydrolysis by the use of microwave oven has been applied to amino acid analysis of proteins and peptides. This convenient method has been compared with the conventional 6 N HCl hydrolysis at 110 degrees for 24 h. The advantages of this new method are its expedition and the accurate and comparable results as compared to the tedious conventional technique. The method provides a rapid processing of multiple samples within minutes instead of days and inexpensive access to the important data of amino acid compositions of proteins by the commonly used microwave oven. The necessary change in the design of hydrolysis vials and the safety precautions accompanying this novel use of microwave acid-digestion method are also described.

  10. Project META (Microwave Energy Transmission for Aircraft)

    Science.gov (United States)

    2009-09-01

    viability of using microwave energy transmission technology to power air vehicles remotely was investigated. On-board antennas ( rectennas ) harvest... rectenna to receive microwave energy and convert it to usable DC power. A prototype was designed and experimentally tested under controlled...beamed energy, beaming energy, remotely powered aircraft, rectenna , microwave propulsion 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF

  11. Recent Advancements in Microwave Imaging Plasma Diagnostics

    Energy Technology Data Exchange (ETDEWEB)

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

    2002-03-26

    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.

  12. 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...

  13. Advanced Microwave Electrothermal Thruster (AMET) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Orbital Technologies Corporation (ORBITEC) and the University of Alabama at Huntsville (UAH) propose to develop the Advanced Microwave Electrothermal Thruster...

  14. 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

  15. Investigating the value of passive microwave observations for monitoring volcanic eruption source parameters

    Science.gov (United States)

    Montopoli, Mario; Cimini, Domenico; Marzano, Frank

    2016-04-01

    the dispersal fine-ash cloud, but tend to saturate near the source due to the strong optical extinction of ash cloud top layers. Conversely, observations at microwave (MW) channels from LEO satellites have demonstrated to carry additional information near the volcano source due to the relative lower opacity. This feature makes satellite MW complementary to IR radiometry for estimating source parameters close to the volcano emission, at the cost of coarser spatial resolution. The presentation shows the value of passive MW observations for the detection and quantitative retrieval of volcanic emission source parameters through the investigation of notable case studies, such as the eruptions of Grímsvötn (Iceland, May 2011) and Calbuco (Cile, April 2015), observed by the Special Sensor Microwave Imager/Sounder and the Advanced Technology Microwave Sounder.

  16. [New technology for linear colliders]. Annual progress report and renewal proposal

    Energy Technology Data Exchange (ETDEWEB)

    McIntyre, P.M.

    1992-08-12

    This report discusses the following topics on research of microwave amplifiers for linear colliders: Context in current microwave technology development; gated field emission for microwave cathodes; cathode fabrication and tests; microwave cathode design using field emitters; and microwave localization.

  17. GPM GROUND VALIDATION SPECIAL SENSOR MICROWAVE IMAGER/SOUNDER (SSMI/S) LPVEX V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The SSMI/S LPVEX dataset contains brightness temperature data processed from the NOAA CLASS QC temperature data records for the Light Precipitation Validation...

  18. Software safety analysis activities during software development phases of the Microwave Limb Sounder (MLS)

    Science.gov (United States)

    Shaw, Hui-Yin; Sherif, Joseph S.

    2004-01-01

    This paper describes the MLS software safety analysis activities and documents the SSA results. The scope of this software safety effort is consistent with the MLS system safety definition and is concentrated on the software faults and hazards that may have impact on the personnel safety and the environment safety.

  19. The 2003 edition of geisa: a spectroscopic database system for the second generation vertical sounders radiance simulation

    Science.gov (United States)

    Jacquinet-Husson, N.; Lmd Team

    The GEISA (Gestion et Etude des Informations Spectroscopiques Atmosphériques: Management and Study of Atmospheric Spectroscopic Information) computer accessible database system, in its former 1997 and 2001 versions, has been updated in 2003 (GEISA-03). It is developed by the ARA (Atmospheric Radiation Analysis) group at LMD (Laboratoire de Météorologie Dynamique, France) since 1974. This early effort implemented the so-called `` line-by-line and layer-by-layer '' approach for forward radiative transfer modelling action. The GEISA 2003 system comprises three databases with their associated management softwares: a database of spectroscopic parameters required to describe adequately the individual spectral lines belonging to 42 molecules (96 isotopic species) and located in a spectral range from the microwave to the limit of the visible. The featured molecules are of interest in studies of the terrestrial as well as the other planetary atmospheres, especially those of the Giant Planets. a database of absorption cross-sections of molecules such as chlorofluorocarbons which exhibit unresolvable spectra. a database of refractive indices of basic atmospheric aerosol components. Illustrations will be given of GEISA-03, data archiving method, contents, management softwares and Web access facilities at: http://ara.lmd.polytechnique.fr The performance of instruments like AIRS (Atmospheric Infrared Sounder; http://www-airs.jpl.nasa.gov) in the USA, and IASI (Infrared Atmospheric Sounding Interferometer; http://smsc.cnes.fr/IASI/index.htm) in Europe, which have a better vertical resolution and accuracy, compared to the presently existing satellite infrared vertical sounders, is directly related to the quality of the spectroscopic parameters of the optically active gases, since these are essential input in the forward models used to simulate recorded radiance spectra. For these upcoming atmospheric sounders, the so-called GEISA/IASI sub-database system has been elaborated

  20. The Impact of Atmospheric InfraRed Sounder (AIRS) Profiles on Short-term Weather Forecasts

    Science.gov (United States)

    Chou, Shih-Hung; Zavodsky, Brad; Jedlovec, Gary J.; Lapenta, William

    2007-01-01

    The Atmospheric Infrared Sounder (AIRS), together with the Advanced Microwave Sounding Unit (AMSU), represents one of the most advanced spacebased atmospheric sounding systems. The combined AlRS/AMSU system provides radiance measurements used to retrieve temperature profiles with an accuracy of 1 K over 1 km layers under both clear and partly cloudy conditions, while the accuracy of the derived humidity profiles is 15% in 2 km layers. Critical to the successful use of AIRS profiles for weather and climate studies is the use of profile quality indicators and error estimates provided with each profile Aside form monitoring changes in Earth's climate, one of the objectives of AIRS is to provide sounding information of sufficient accuracy such that the assimilation of the new observations, especially in data sparse region, will lead to an improvement in weather forecasts. The purpose of this paper is to describe a procedure to optimally assimilate highresolution AIRS profile data in a regional analysis/forecast model. The paper will focus on the impact of AIRS profiles on a rapidly developing east coast storm and will also discuss preliminary results for a 30-day forecast period, simulating a quasi-operation environment. Temperature and moisture profiles were obtained from the prototype version 5.0 EOS science team retrieval algorithm which includes explicit error information for each profile. The error profile information was used to select the highest quality temperature and moisture data for every profile location and pressure level for assimilation into the ARPS Data Analysis System (ADAS). The AIRS-enhanced analyses were used as initial fields for the Weather Research and Forecast (WRF) system used by the SPORT project for regional weather forecast studies. The ADASWRF system will be run on CONUS domain with an emphasis on the east coast. The preliminary assessment of the impact of the AIRS profiles will focus on quality control issues associated with AIRS

  1. Impact of Atmospheric Infrared Sounder (AIRS) Thermodynamic Profiles on Regional Weather Forecasting

    Science.gov (United States)

    Chou, Shih-Hung; Zavodsky, Bradley T.; Jedlovee, Gary J.

    2010-01-01

    In data sparse regions, remotely-sensed observations can be used to improve analyses and lead to better forecasts. One such source comes from the Atmospheric Infrared Sounder (AIRS), which together with the Advanced Microwave Sounding Unit (AMSU), provides temperature and moisture profiles with accuracy comparable to that of radiosondes. The purpose of this paper is to describe a procedure to assimilate AIRS thermodynamic profile data into a regional configuration of the Advanced Research Weather Research and Forecasting (WRF-ARW) model using its three-dimension variational (3DVAR) analysis component (WRF-Var). Quality indicators are used to select only the highest quality temperature and moisture profiles for assimilation in both clear and partly cloudy regions. Separate error characteristics for land and water profiles are also used in the assimilation process. Assimilation results indicate that AIRS profiles produce an analysis closer to in situ observations than the background field. Forecasts from a 37-day case study period in the winter of 2007 show that AIRS profile data can lead to improvements in 6-h cumulative precipitation forecasts due to instability added in the forecast soundings by the AIRS profiles. Additionally, in a convective heavy rainfall event from February 2007, assimilation of AIRS profiles produces a more unstable boundary layer resulting in enhanced updrafts in the model. These updrafts produce a squall line and precipitation totals that more closely reflect ground-based observations than a no AIRS control forecast. The location of available high-quality AIRS profiles ahead of approaching storm systems is found to be of paramount importance to the amount of impact the observations will have on the resulting forecasts.

  2. Impact of Atmospheric Infrared Sounder (AIRS) Thermodynamic Profiles on Regional Precipitation Forecasting

    Science.gov (United States)

    Chou, S.-H.; Zavodsky, B. T.; Jedloved, G. J.

    2010-01-01

    In data sparse regions, remotely-sensed observations can be used to improve analyses and lead to better forecasts. One such source comes from the Atmospheric Infrared Sounder (AIRS), which together with the Advanced Microwave Sounding Unit (AMSU), provides temperature and moisture profiles in clear and cloudy regions with accuracy which approaches that of radiosondes. The purpose of this paper is to describe an approach to assimilate AIRS thermodynamic profile data into a regional configuration of the Advanced Research WRF (ARW) model using WRF-Var. Quality indicators are used to select only the highest quality temperature and moisture profiles for assimilation in clear and partly cloudy regions, and uncontaminated portions of retrievals above clouds in overcast regions. Separate error characteristics for land and water profiles are also used in the assimilation process. Assimilation results indicate that AIRS profiles produce an analysis closer to in situ observations than the background field. Forecasts from a 37-day case study period in the winter of 2007 show that AIRS profile data can lead to improvements in 6-h cumulative precipitation forecasts resulting from improved thermodynamic fields. Additionally, in a convective heavy rainfall event from February 2007, assimilation of AIRS profiles produces a more unstable boundary layer resulting in enhanced updrafts in the model. These updrafts produce a squall line and precipitation totals that more closely reflect ground-based observations than a no AIRS control forecast. The location of available high-quality AIRS profiles ahead of approaching storm systems is found to be of paramount importance to the amount of impact the observations will have on the resulting forecasts.

  3. 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

  4. Satellite Sounder Data Assimilation for Improving Alaska Region Weather Forecast

    Science.gov (United States)

    Zhu, Jiang; Stevens, E.; Zavodsky, B. T.; Zhang, X.; Heinrichs, T.; Broderson, D.

    2014-01-01

    Data assimilation has been demonstrated very useful in improving both global and regional numerical weather prediction. Alaska has very coarser surface observation sites. On the other hand, it gets much more satellite overpass than lower 48 states. How to utilize satellite data to improve numerical prediction is one of hot topics among weather forecast community in Alaska. The Geographic Information Network of Alaska (GINA) at University of Alaska is conducting study on satellite data assimilation for WRF model. AIRS/CRIS sounder profile data are used to assimilate the initial condition for the customized regional WRF model (GINA-WRF model). Normalized standard deviation, RMSE, and correlation statistic analysis methods are applied to analyze one case of 48 hours forecasts and one month of 24-hour forecasts in order to evaluate the improvement of regional numerical model from Data assimilation. The final goal of the research is to provide improved real-time short-time forecast for Alaska regions.

  5. 3D Reconfigurable NoC Multiprocessor Portable Sounder for Plasmaspheric Studies

    Science.gov (United States)

    Dekoulis, George

    2016-07-01

    The paper describes the development of a prototype imaging sounder for studying the irregularities of the ionospheric plasma. Cutting edge three-dimensional reconfigurable logic has been implemented allowing highly-intensive scientific calculations to be performed in hardware. The new parallel processing algorithms implemented offer a significant amount of performance improvement in the range of 80% compared to existing digital sounder implementations. The current system configuration is taking into consideration the modern scientific needs for portability during scientific campaigns. The prototype acts as a digital signal processing experimentation platform for future larger-scale digital sounder instrumentations for measuring complex planetary plasmaspheric environments.

  6. NIMBUS-5 sounder data processing system. Part 2: Results

    Science.gov (United States)

    Smith, W. L.; Woolf, H. M.; Hayden, C. M.; Shen, W. C.

    1975-01-01

    The Nimbus-5 spacecraft carries infrared and microwave radiometers for sensing the temperature distribution of the atmosphere. Methods developed for obtaining temperature profiles from the combined set of infrared and microwave radiation measurements are described. Algorithms used to determine (a) vertical temperature and water vapor profiles, (b) cloud height, fractional coverage, and liquid water content, (c) surface temperature, and (d) total outgoing longwave radiation flux are described. Various meteorological results obtained from the application of the Nimbus-5 sounding data processing system during 1973 and 1974 are presented.

  7. 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

  8. Microwave applications of soft ferrites

    CERN Document Server

    Pardavi-Horvath, M P

    2000-01-01

    Signal processing requires broadband, low-loss, low-cost microwave devices (circulators, isolators, phase shifters, absorbers). Soft ferrites (garnets, spinels, hexaferrites), applied in planar microwave devices, are reviewed from the point of view of device requirements. Magnetic properties, specific to operation in high-frequency electromagnetic fields, are discussed. Recent developments in thick film ferrite technology and device design are reviewed. Magnetic losses related to planar shape and inhomogeneous internal fields are analyzed.

  9. UARS Improved Stratospheric and Mesospheric Sounder (ISAMS) Level 3AT V001

    Data.gov (United States)

    National Aeronautics and Space Administration — The Improved Stratospheric and Mesospheric Sounder (ISAMS) Level 3AT data product consists of daily, 65.536 second interval time-ordered vertical profiles of...

  10. UARS Improved Stratospheric and Mesospheric Sounder (ISAMS) Level 3AL V001

    Data.gov (United States)

    National Aeronautics and Space Administration — The Improved Stratospheric and Mesospheric Sounder (ISAMS) Level 3AL data product consists of daily, 4 degree increment latitude-ordered vertical profiles of...

  11. Optimal Use of Space-Borne Advanced Infrared and Microwave Soundings for Regional Numerical Weather Prediction

    Directory of Open Access Journals (Sweden)

    Chian-Yi Liu

    2016-09-01

    Full Text Available Satellite observations can either be assimilated as radiances or as retrieved physical parameters to reduce error in the initial conditions used by the Numerical Weather Prediction (NWP model. Assimilation of radiances requires a radiative transfer model to convert atmospheric state in model space to that in radiance space, thus requiring a lot of computational resources especially for hyperspectral instruments with thousands of channels. On the other hand, assimilating the retrieved physical parameters is computationally more efficient as they are already in thermodynamic states, which can be compared with NWP model outputs through the objective analysis scheme. A microwave (MW sounder and an infrared (IR sounder have their respective observational limitation due to the characteristics of adopted spectra. The MW sounder observes at much larger field-of-view (FOV compared to an IR sounder. On the other hand, MW has the capability to reveal the atmospheric sounding when the clouds are presented, but IR observations are highly sensitive to clouds, The advanced IR sounder is able to reduce uncertainties in the retrieved atmospheric temperature and moisture profiles due to its higher spectral-resolution than the MW sounder which has much broader spectra bands. This study tries to quantify the optimal use of soundings retrieved from the microwave sounder AMSU and infrared sounder AIRS onboard the AQUA satellite in the regional Weather and Research Forecasting (WRF model through three-dimensional variational (3D-var data assimilation scheme. Four experiments are conducted by assimilating soundings from: (1 clear AIRS single field-of-view (SFOV; (2 retrieved from using clear AMSU and AIRS observations at AMSU field-of-view (SUP; (3 all SFOV soundings within AMSU FOVs must be clear; and (4 SUP soundings which must have all clear SFOV soundings within the AMSU FOV. A baseline experiment assimilating only conventional data is generated for comparison

  12. 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.

  13. Simulation study for the Stratospheric Inferred Wind (SIW) sub-millimeter limb sounder

    Science.gov (United States)

    Baron, Philippe; Murtagh, Donal; Eriksson, Patrick; Ochiai, Satoshi

    2017-04-01

    -and-aac-microtec-to-develop-the-innosat-platform-and-implement-its-first-mission-named-mats.html [2] Wu D., et al.: Mesospheric Doppler wind measurements from Aura Microwave Limb Sounder (MLS), Advanced in Space Research, 42, 1246-1252, 2008 [3] Baron P., et al.: Observation of horizontal winds in the middle-atmosphere between 30S and 55N during the northern winter 2009-2010, Atmospheric Chemistry and Physics 13(13), 6049-6064, 2013, doi:10.5194/acp-13-6049-2013 [4] Baron P., et al.: Definition of an uncooled submillimeter/terahertz limb sounder for measuring middle atmospheric winds, Proceedings of ESA Living Planet Symposium, Edinburgh, UK, 9-13 September 2013, (ESA SP-722, December 2013)

  14. Sensitivity Analysis for Atmospheric Infrared Sounder (AIRS) CO2 Retrieval

    Science.gov (United States)

    Gat, Ilana

    2012-01-01

    The Atmospheric Infrared Sounder (AIRS) is a thermal infrared sensor able to retrieve the daily atmospheric state globally for clear as well as partially cloudy field-of-views. The AIRS spectrometer has 2378 channels sensing from 15.4 micrometers to 3.7 micrometers, of which a small subset in the 15 micrometers region has been selected, to date, for CO2 retrieval. To improve upon the current retrieval method, we extended the retrieval calculations to include a prior estimate component and developed a channel ranking system to optimize the channels and number of channels used. The channel ranking system uses a mathematical formalism to rapidly process and assess the retrieval potential of large numbers of channels. Implementing this system, we identifed a larger optimized subset of AIRS channels that can decrease retrieval errors and minimize the overall sensitivity to other iridescent contributors, such as water vapor, ozone, and atmospheric temperature. This methodology selects channels globally by accounting for the latitudinal, longitudinal, and seasonal dependencies of the subset. The new methodology increases accuracy in AIRS CO2 as well as other retrievals and enables the extension of retrieved CO2 vertical profiles to altitudes ranging from the lower troposphere to upper stratosphere. The extended retrieval method for CO2 vertical profile estimation using a maximum-likelihood estimation method. We use model data to demonstrate the beneficial impact of the extended retrieval method using the new channel ranking system on CO2 retrieval.

  15. Global and regional seasonal variability of mid-tropospheric CO2 as measured by the Atmospheric Infrared Sounder (AIRS)

    Science.gov (United States)

    Pagano, Thomas S.; Olsen, Edward T.; Nguyen, Hai

    2012-09-01

    The Atmospheric Infrared Sounder (AIRS) is a hyperspectral infrared instrument on the Earth Observing System (EOS) Aqua Spacecraft, launched on May 4, 2002 into a near polar sun-synchronous orbit. AIRS has 2378 infrared channels ranging from 3.7 μm to 15.4 μm and a 13.5 km footprint at nadir. AIRS, in conjunction with the Advanced Microwave Sounding Unit (AMSU), produces temperature profiles with 1K/km accuracy on a global scale, as well as water vapor profiles and trace gas amounts for CO2, CO, SO2, O3 and CH4. AIRS CO2 climatologies have been shown to be useful for identifying anomalies associated with geophysical events such as El Niño-Southern Oscillation or Madden-Julian oscillation. In this study, monthly representations of mid-tropospheric CO2 are constructed from 10 years of AIRS Version 5 monthly Level 3 data. We compare the AIRS mid-tropospheric CO2 representations to ground-based measurements from the Scripps and National Oceanic and Atmospheric Administration Climate Modeling and Diagnostics Laboratory (NOAA CMDL) ground networks to better understand the phase lag of the CO2 seasonal cycle between the surface and middle troposphere. Results show only a small phase lag in the tropics that grows to approximately two months in the northern latitudes.

  16. Microwave dielectric properties of nanostructured nickel ferrite

    Indian Academy of Sciences (India)

    Wintec

    ... microwave dielectric; co-precipitation. 1. Introduction. Ferrites find wide technological applications in making cores of audio frequency and high frequency transformers, coils (inductors), chokes, permanent magnets, magneto- optical displays, microwave absorbers, wave guides in the. GHz region and chlorine gas sensors ...

  17. Compact superconducting coplanar microwave beam splitters

    Energy Technology Data Exchange (ETDEWEB)

    Baust, Alexander; Haeberlein, Max; Goetz, Jan; Hoffmann, Elisabeth; Menzel, Edwin P.; Schwarz, Manuel J.; Wulschner, Friedrich; Zhong, Ling; Deppe, Frank; Marx, Achim; Gross, Rudolf [Walther-Meissner-Institut, Bayerische Akademie der Wissenschaften, Garching (Germany); Physik-Department, TUM, Garching (Germany); Kalb, Norbert; Losinger, Thomas [Physik-Department, TUM, Garching (Germany)

    2012-07-01

    The recent evolution of circuit quantum electrodynamics systems making use of standing-wave microwave modes towards setups for propagating quantum microwaves has triggered the need for low-loss superconducting microwave beam splitters. Such a device should have ports compatible with the coplanar geometry relevant for circuit QED and, at the same time, be compact allowing for scalability. This combination presents fundamental and technological challenges. In this work, we present the fabrication and characterization of various compact superconducting coplanar microwave beam splitters. In addition, we discuss efforts towards a tunable beam splitter.

  18. Simple microwave preionization source for ohmic plasmas

    Science.gov (United States)

    Choe, W.; Kwon, Gi-Chung; Kim, Junghee; Kim, Jayhyun; Jeon, Sang-Jean; Huh, Songwhe

    2000-07-01

    A simple economical 2.45 GHz microwave system has been developed and utilized for preionization on the Korea Advanced Institute of Science and Technology (KAIST)-TOKAMAK. The magnetron microwave source was obtained from a widely used, household microwave oven. Since ac operation of the magnetron is not suitable for tokamak application, the magnetron cathode bias circuit was modified to obtain continuous and stable operation of the magnetron for several hundred milliseconds. Application of the developed microwave system to KAIST-TOKAMAK resulted in a reduction of ohmic flux consumption.

  19. 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.

  20. Geometry-based channel modelling of MIMO channels in comparison with channel sounder measurements

    Directory of Open Access Journals (Sweden)

    G. Del Galdo

    2004-01-01

    Full Text Available In this paper we propose a flexible geometrybased propagation model for wireless communications developed at Ilmenau University of Technology. The IlmProp comprises a geometrical representation of the environment surrounding the experiment and a precise representation of the transmitting and receiving antennas. The IlmProp is capable of simulating Multi-User MIMO scenarios and includes a complete collection of tools to analyze the synthetic channels. In order to assess the potentials as well as the limits of our channel simulator we reconstruct the scenario encountered in a recent measurement campaign at Ilmenau University of Technology leading to synthetic data sets similar to the ones actually measured. The measurements have been collected with the RUSK MIMO multi-dimensional channel sounder. From the comparisons of the two channel matrices it is possible to derive useful information to improve the model itself and to better understand the physical origins of small-scale fading. In particular the effects of the different parameters on the synthetic channel have been studied in order to assess the sensibility of the model. This analysis shows that the correct positioning of a small number of scatterers is enough to achieve frequency selectiveness as well as specific traits of the channel statistics. The size of the scattering clusters, the number of scatterers per cluster, and the Rician K-factor can be modified in order to tune the channel statistics at will. To obtain higher levels of time variance, moving scatterers or time dependent reflection coefficients must be introduced.

  1. The Magnetic INduction Ocean Sounder (MINOS) Concept Mission: Exploring Small Ocean Worlds With Nanosatellites

    Science.gov (United States)

    Steuer, C. J.

    2016-12-01

    Nanosatellite capabilities continue to steadily increase, showcasing ongoing advancement in key systems including GNC, communications, and power utilization. With focused high impact payloads, these small spacecraft can produce extraordinarily valuable planetary science datasets previously only retrievable by large, expensive, flagship science missions. The new capabilities provided by these nano-class spacecraft, in conjunction with, or even in lieu of, more traditional large monolithic spacecraft, can clear the way for a paradigm shift in the logistics and architecture of planetary science missions. Key near term targets for this technology are the icy moons of the outer solar system where advances in propulsion technology coupled with the low mass of nanosatellites and the shallow gravity wells of the moons allow for orbital capture. As part of a JPL funded study, the authors investigated the feasibility of placing a nanosatellite with magnetometer payload in Europa orbit to enhance and compliment the upcoming flagship mission to Europa through multi-frequency magnetic induction sounding. The study concluded that the enhanced dataset provided by coordinated observation between flagship, in Jovian orbit, and nanosatellite, in Europa orbit, using a fluxgate magnetometer of Rosetta heritage, would enable a more complete understanding of Europa's induction response by providing synchronous datasets between the Jovian plasma torus and the induced magnetosphere of Europa. We propose that these Magnetic INduction Ocean Sounders or MINOS spacecraft can play a similar role for all of the icy moons of the Jovian and Saturnian systems, providing close proximity multi-period magnetic induction sounding to compliment plasma suites and ice penetrating radar while setting the stage for alternative payloads and enhanced exploration of these potentially habitable worlds.

  2. Seasonal and diel patterns in sedimentary flux of krill fecal pellets recorded by an echo sounder

    KAUST Repository

    Røstad, Anders

    2013-11-01

    We used a moored upward-facing 200 kHz echo sounder to address sedimentation of fecal pellets (FPs) from dielly migrating Meganyctiphanes norvegica. The echo sounder was located on the bottom at 150 m depth in the Oslofjord, Norway, and was cabled to shore for continuous measurements during winter and spring. Records of sinking pellets were for the first time observed with an echo sounder. Seasonal patterns of sedimentation of krill FPs were strongly correlated with data from continuous measurement of fluorescence, which illustrate the development of the spring bloom. Sedimenting particles were first observed as fluorescence values started to increase at the end of February and continued to increase until the bloom suddenly culminated at the end of March. This collapse of the bloom was detected on the echo sounder as a pulse of slowly sinking acoustic targets over a 2 d period. Prior to this event, there was a strong diel pattern in sedimentation, which correlated, with some time lag, with the diel migration of krill foraging at night near the surface. Pellet average sinking speeds ranged between 423 m d−1 and 804 m d−1, with a strong relation to pellet target strength, which is an acoustic proxy for size. This novel approach shows that echo sounders may be a valuable tool in studies of vertical pellet flux and, thereby, carbon flux, providing temporal resolution and direct observation of the sedimentation process, which are not obtained from standard methods.

  3. Microwave Filters

    OpenAIRE

    Zhou, Jiafeng

    2010-01-01

    The general theory of microwave filter design based on lumped-element circuit is described in this chapter. The lowpass prototype filters with Butterworth, Chebyshev and quasielliptic characteristics are synthesized, and the prototype filters are then transformed to bandpass filters by lowpass to bandpass frequency mapping. By using immitance inverters ( J - or K -inverters), the bandpass filters can be realized by the same type of resonators. One design example is given to verify the theory ...

  4. Microwave remote sensing from space

    Science.gov (United States)

    Carver, K. R.; Elachi, C.; Ulaby, F. T.

    1985-01-01

    Spaceborne microwave remote sensors provide perspectives of the earth surface and atmosphere which are of unique value in scientific studies of geomorphology, oceanic waves and topography, atmospheric water vapor and temperatures, vegetation classification and stress, ice types and dynamics, and hydrological characteristics. Microwave radars and radiometers offer enhanced sensitivities to the geometrical characteristics of the earth's surface and its cover, to water in all its forms - soil and vegetation moisture, ice, wetlands, oceans, and atmospheric water vapor, and can provide high-resolution imagery of the earth's surface independent of cloud cover or sun angle. A brief review of the historical development and principles of active and passive microwave remote sensing is presented, with emphasis on the unique characteristics of the information obtainable in the microwave spectrum and the value of this information to global geoscientific studies. Various spaceborne microwave remote sensors are described, with applications to geology, planetology, oceanography, glaciology, land biology, meteorology, and hydrology. A discussion of future microwave remote sensor technological developments and challenges is presented, along with a summary of future missions being planned by several countries.

  5. 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.

  6. Microwave Drying of Moist Coals

    Science.gov (United States)

    Salomatov, Vl. V.; Karelin, V. A.; Sladkov, S. O.; Salomatov, Vas. V.

    2017-03-01

    Physical principles and examples of practical implementation of drying large bodies of coal by microwave radiation are considered. It is shown that energy consumption in microwave drying of brown coals decreases to 1.5-1.8 (kW·h)/ kg as compared with traditional types of drying, for which the expenditures of energy amount to 3.0 (kW·h)/kg. In using microwave drying, the technological time of drying decreases to 4 h, whereas the time of convective drying, with other things being equal, comes to 8-20 h. Parallel with microwave radiation drying, grinding of a fuel takes place, as well as entrainment of such toxic and ecologically harmful elements as mercury, chlorine, phosphorus, sulfur, and nitrogen. An analysis of the prospects of using a microwave energy for drying coal fuel has shown that microwave radiation makes it possible to considerably economize in energy, increase explosional safety, improve the ecological situation, and reduce the metal content and overall dimensions of the equipment.

  7. Thermal Band Atmospheric Correction Using Atmospheric Profiles Derived from Global Positioning System Radio Occultation and the Atmospheric Infrared Sounder

    Science.gov (United States)

    Pagnutti, Mary; Holekamp, Kara; Stewart, Randy; Vaughan, Ronald D.

    2006-01-01

    This Rapid Prototyping Capability study explores the potential to use atmospheric profiles derived from GPS (Global Positioning System) radio occultation measurements and by AIRS (Atmospheric Infrared Sounder) onboard the Aqua satellite to improve surface temperature retrieval from remotely sensed thermal imagery. This study demonstrates an example of a cross-cutting decision support technology whereby NASA data or models are shown to improve a wide number of observation systems or models. The ability to use one data source to improve others will be critical to the GEOSS (Global Earth Observation System of Systems) where a large number of potentially useful systems will require auxiliary datasets as input for decision support. Atmospheric correction of thermal imagery decouples TOA radiance and separates surface emission from atmospheric emission and absorption. Surface temperature can then be estimated from the surface emission with knowledge of its emissivity. Traditionally, radiosonde sounders or atmospheric models based on radiosonde sounders, such as the NOAA (National Oceanic & Atmospheric Administration) ARL (Air Resources Laboratory) READY (Real-time Environmental Application and Display sYstem), provide the atmospheric profiles required to perform atmospheric correction. Unfortunately, these types of data are too spatially sparse and too infrequently taken. The advent of high accuracy, global coverage, atmospheric data using GPS radio occultation and AIRS may provide a new avenue for filling data input gaps. In this study, AIRS and GPS radio occultation derived atmospheric profiles from the German Aerospace Center CHAMP (CHAllenging Minisatellite Payload), the Argentinean Commission on Space Activities SAC-C (Satellite de Aplicaciones Cientificas-C), and the pair of NASA GRACE (Gravity Recovery and Climate Experiment) satellites are used as input data in atmospheric radiative transport modeling based on the MODTRAN (MODerate resolution atmospheric

  8. Ultra-Wideband Channel Sounder – Design, Construction and Selected Applications

    Directory of Open Access Journals (Sweden)

    R. Zetik

    2013-06-01

    Full Text Available The paper describes construction, design, and application of a real-time ultra-wideband channel sounder. Its specific architecture allows measurements of time-variant radio propagation channels in different frequency bands. The sounder’s stimulation signal is the maximum length binary sequence. Synchronous multi-channel operation is supported by its excellent timing stability and by its low power consumption of miniature sized low temperature co-fired ceramics modules that comprise custom integrated SiGe circuits. This is a prerequisite to build a multiple-input-multiple-output sounder which is suitable for sounding even in distributed scenarios such as sensor networks. Selected application examples demonstrated the performance and possibilities of the sounder.

  9. Silicon nitride microwave photonic circuits

    NARCIS (Netherlands)

    Roeloffzen, C.G.H.; Zhuang, L.; Taddei, Caterina; Taddei, Caterina; Leinse, Arne; Heideman, Rene; van Dijk, Paulus W.L.; Oldenbeuving, Ruud; Marpaung, D.A.I.; Burla, M.; Buria, Maurizio; Boller, Klaus J.

    2013-01-01

    We present an overview of several microwave photonic processing functionalities based on combinations of Mach-Zehnder and ring resonator filters using the high index contrast silicon nitride (TriPleXTM) waveguide technology. All functionalities are built using the same basic building blocks, namely

  10. Suomi NPP ATMS Level 1B Brightness Temperature V1 (SNPPATMSL1B) at GES DISC

    Data.gov (United States)

    National Aeronautics and Space Administration — The Advanced Technology Microwave Sounder (ATMS) Level 1B data files contain brightness temperature measurements along with ancillary spacecraft, instrument, and...

  11. Microwave and Pulsed Power

    Energy Technology Data Exchange (ETDEWEB)

    Freytag, E.K.

    1993-03-01

    The goals of the Microwave and Pulsed Power thrust area are to identify realizable research and development efforts and to conduct high-quality research in those pulse power and microwave technologies that support existing and emerging programmatic requirements at Lawrence Livermore National Laboratory (LLNL). Our main objective is to work on nationally important problems while enhancing our basic understanding of enabling technologies such as component design and testing, compact systems packaging, exploratory physics experiments, and advanced systems integration and performance. During FY-92, we concentrated our research efforts on the six project areas described in this report. (1) We are investigating the superior electronic and thermal properties of diamond that may make it an ideal material for a high-power, solid-state switch. (2) We are studying the feasibility of using advanced Ground Penetrating Imaging Radar technology for reliable non-destructive evaluation of bridges and other high-value concrete structures. These studies include conceptual designs, modeling, experimental verifications, and image reconstruction of simulated radar data. (3) We are exploring the efficiency of pulsed plasma processing techniques used for the removal of NO{sub x} from various effluent sources. (4) We have finished the investigation of the properties of a magnetically delayed low-pressure gas switch, which was designed here at LLNL. (5) We are applying statistical electromagnetic theory techniques to help assess microwave effects on electronic subsystems, by using a mode stirred chamber as our measurement tool. (6) We are investigating the generation of perfluoroisobutylene (PFIB) in proposed CFC replacement fluids when they are subjected to high electrical stresses and breakdown environments.

  12. VHF SoOp (Signal of Opportunity) Technology Demonstration for Soil Moisture Measurement Using Microwave Hydraulic Boom Truck Platform

    Science.gov (United States)

    Joseph, A. T.; Deshpande, M.; O'Neill, P. E.; Miles, L.

    2017-01-01

    A goal of this research is to test deployable VHF antennas for 6U Cubesat platforms to enable validation of root zone soil moisture (RZSM) estimation algorithms for signal of opportunity (SoOp) remote sensing over the 240-270 MHz frequency band. The proposed work provides a strong foundation for establishing a technology development path for maturing a global direct surface soil moisture (SM) and RZSM measurement system over a variety of land covers. Knowledge of RZSM up to a depth of 1 meter and surface SM up to a depth of 0.05 meter on a global scale, at a spatial resolution of 1-10 km through moderate-to-heavy vegetation, is critical to understanding global water resources and the vertical moisture gradient in the Earths surface layer which controls moisture interactions between the soil, vegetation, and atmosphere. Current observations of surface SM from space by L-band radiometers (1.4 GHz) and radars (1.26 GHz) are limited to measurements of surface SM up to a depth of 0.05 meter through moderate amounts of vegetation. This limitation is mainly due to the inability of L-band signals to penetrate through dense vegetation and deep into the soil column. Satellite observations of the surface moisture conditions are coupled to sophisticated models which extrapolate the surface SM into the root zone, thus providing an indirect estimate rather than a direct measurement of RZSM. To overcome this limitation, low-frequency airborne radars operating at 435 MHz and 118 MHz have been investigated, since these lower frequencies should penetrate denser vegetation and respond to conditions deeper in the soil.

  13. VHF SoOp (Signal of Opportunity) Technology Demonstration for Soil Moisture Measurement Using Microwave Hydraulic Boom Truck Platform

    Science.gov (United States)

    Joseph, Alicia; Deshpande, Manohar; O'Neill, Peggy; Miles, Lynn

    2017-04-01

    A goal of this research is to test deployable VHF antennas for 6U Cubesat platforms to enable validation of root zone soil moisture (RZSM) estimation algorithms for signal of opportunity (SoOp) remote sensing over the 240-270 MHz frequency band. The proposed work provides a strong foundation for establishing a technology development path for maturing a global direct surface soil moisture (SM) and RZSM measurement system over a variety of land covers. Knowledge of RZSM up to a depth of 1 meter and surface SM up to a depth of 0.05 meter on a global scale, at a spatial resolution of 1-10 km through moderate-to-heavy vegetation, is critical to understanding global water resources and the vertical moisture gradient in the Earth's surface layer which controls moisture interactions between the soil, vegetation, and atmosphere. Current observations of surface SM from space by L-band radiometers (1.4 GHz) and radars (1.26 GHz) are limited to measurements of surface SM up to a depth of 0.05 meter through moderate amounts of vegetation. This limitation is mainly due to the inability of L-band signals to penetrate through dense vegetation and deep into the soil column. Satellite observations of the surface moisture conditions are coupled to sophisticated models which extrapolate the surface SM into the root zone, thus providing an indirect estimate rather than a direct measurement of RZSM. To overcome this limitation, low-frequency airborne radars operating at 435 MHz and 118 MHz have been investigated, since these lower frequencies should penetrate denser vegetation and respond to conditions deeper in the soil. This presentation describes a new and less expensive technique for SM as well as RZSM direct measurement using Signal of Opportunity transmitters. Being less expensive and needing only passive simple RF receiver, the SoOp concept has the potential for being used for space borne applications, thus providing global SM and RZSM measurements. This study will describe

  14. An introduction to high power microwaves

    Science.gov (United States)

    Benford, James; Swegle, John

    1992-02-01

    The area of high power microwaves has emerged in recent years as a new technology allowing new applications and offering innovative approaches to existing applications. The great leap in microwave power levels has been driven by a mix of sources that either push conventional microwave device physics in new directions or employ altogether new interaction mechanisms. Running counter to the trend in conventional microwave electronics toward miniaturization with solid-state devices intrinsically limited in their peak power capability, high power microwave generation taps the immense power and energy reservoirs of modern intense relativistic electron beam technology. The term high power microwaves (HPM) is used to denote devices that exceed 100 MW in peak power and span the cm- and mm-wave range of frequencies between 1 and 300 GHz. This definition is arbitrary, but does cleanly divide the conventional microwave devices, which do not exceed 100 MW, from a collection of microwave-generating devices that have now reached powers as high as 15 GW.

  15. Microwave Sterilization and Depyrogenation System

    Science.gov (United States)

    Akse, James R.; Dahl, Roger W.; Wheeler, Richard R., Jr.

    2009-01-01

    at a given flow rate. These technologies can be employed in small-scale systems for efficient production of MGW in the laboratory or in a range of larger systems that meet various industrial requirements. The microwave antennas can also be adapted to selectively sterilize vulnerable connections to ultra-pure water production facilities or biologically vulnerable systems where microorganisms may intrude.

  16. Total column ozone retrieval using INSAT-3D sounder in the tropics ...

    Indian Academy of Sciences (India)

    The present study examines the potential of infrared sounder observations from Indian geostationary satellite INSAT-3D for the estimation of total column integrated ozone over the tropical Indian region. A dataset with diverse profiles was used to create training and testing datasets using forward simulations from a radiative ...

  17. Whisper, a resonance sounder and wave analyser: Performances and perspectives for the Cluster mission

    DEFF Research Database (Denmark)

    Decreau, P.M.E.; Fergeau, P.; KrannoselsKikh, V.

    1997-01-01

    The WHISPER sounder on the Cluster spacecraft is primarily designed to provide an absolute measurement of the total plasma density within the range 0.2-80 cm(-3). This is achieved by means of a resonance sounding technique which has already proved successful in the regions to be explored. The wav...

  18. P-sounder: an airborne P-band ice sounding radar

    DEFF Research Database (Denmark)

    Dall, Jørgen; Skou, Niels; Kusk, Anders

    2007-01-01

    This paper presents the top-level design of an airborne, P-band ice sounding radar under development at the Technical University of Denmark. The ice sounder is intended to provide more information on the electromagnetic properties of the Antarctic ice sheet at P-band. A secondary objective...

  19. Deep convective cloud characterizations from both broadband imager and hyperspectral infrared sounder measurements

    Science.gov (United States)

    Ai, Yufei; Li, Jun; Shi, Wenjing; Schmit, Timothy J.; Cao, Changyong; Li, Wanbiao

    2017-02-01

    Deep convective storms have contributed to airplane accidents, making them a threat to aviation safety. The most common method to identify deep convective clouds (DCCs) is using the brightness temperature difference (BTD) between the atmospheric infrared (IR) window band and the water vapor (WV) absorption band. The effectiveness of the BTD method for DCC detection is highly related to the spectral resolution and signal-to-noise ratio (SNR) of the WV band. In order to understand the sensitivity of BTD to spectral resolution and SNR for DCC detection, a BTD to noise ratio method using the difference between the WV and IR window radiances is developed to assess the uncertainty of DCC identification for different instruments. We examined the case of AirAsia Flight QZ8501. The brightness temperatures (Tbs) over DCCs from this case are simulated for BTD sensitivity studies by a fast forward radiative transfer model with an opaque cloud assumption for both broadband imager (e.g., Multifunction Transport Satellite imager, MTSAT-2 imager) and hyperspectral IR sounder (e.g., Atmospheric Infrared Sounder) instruments; we also examined the relationship between the simulated Tb and the cloud top height. Results show that despite the coarser spatial resolution, BTDs measured by a hyperspectral IR sounder are much more sensitive to high cloud tops than broadband BTDs. As demonstrated in this study, a hyperspectral IR sounder can identify DCCs with better accuracy.

  20. Development and characterization of the superconducting integrated receiver channel of the TELIS atmospheric sounder

    NARCIS (Netherlands)

    De Lange, Gert; Birk, Manfred; Boersma, Dick; Dercksen, Johannes; Dmitriev, Pavel; Ermakov, Andrey B.; Filippenko, Lyudmila V.; Golstein, Hans; Hoogeveen, Ruud W. M.; de Jong, Leo; Khudchenko, Andrey V.; Kinev, Nickolay V.; Kiselev, Oleg S.; van Kuik, Bart; de Lange, Arno; van Rantwijk, Joris; Selig, Avri M.; Sobolev, Alexander S.; Torgashin, Mikhail Yu; de Vries, Ed; Wagner, Georg; Yagoubov, Pavel A.; Koshelets, Valery P.

    The balloon-borne instrument TELIS (TErahertz and submillimetre LImb Sounder) is a three-channel superconducting heterodyne spectrometer for atmospheric research use. It detects spectral emission lines of stratospheric trace gases that have their rotational transitions at THz frequencies. One of the

  1. 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.

  2. 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.)

  3. Microwave Treatment for Cardiac Arrhythmias

    Science.gov (United States)

    Hernandez-Moya, Sonia

    2009-01-01

    NASA seeks to transfer the NASA developed microwave ablation technology, designed for the treatment of ventricular tachycardia (irregular heart beat), to industry. After a heart attack, many cells surrounding the resulting scar continue to live but are abnormal electrically; they may conduct impulses unusually slowly or fire when they would typically be silent. These diseased areas might disturb smooth signaling by forming a reentrant circuit in the muscle. The objective of microwave ablation is to heat and kill these diseased cells to restore appropriate electrical activity in the heart. This technology is a method and apparatus that provides for propagating microwave energy into heart tissues to produce a desired temperature profile therein at tissue depths sufficient for thermally ablating arrhythmogenic cardiac tissue while preventing excessive heating of surrounding tissues, organs, and blood. A wide bandwidth double-disk antenna is effective for this purpose over a bandwidth of about six gigahertz. A computer simulation provides initial screening capabilities for an antenna such as antenna, frequency, power level, and power application duration. The simulation also allows optimization of techniques for specific patients or conditions. In comparison with other methods that involve direct-current pulses or radio frequencies below 1 GHz, this method may prove more effective in treating ventricular tachycardia. This is because the present method provides for greater control of the location, cross-sectional area, and depth of a lesion via selection of the location and design of the antenna and the choice of microwave power and frequency.

  4. UARS Improved Stratospheric and Mesospheric Sounder (ISAMS) Level 3AL V010 (UARIS3AL) at GES DISC

    Data.gov (United States)

    National Aeronautics and Space Administration — The Improved Stratospheric and Mesospheric Sounder (ISAMS) Level 3AL data product consists of daily, 4 degree increment latitude-ordered vertical profiles of...

  5. UARS Improved Stratospheric and Mesospheric Sounder (ISAMS) Level 3AT V010 (UARIS3AT) at GES DISC

    Data.gov (United States)

    National Aeronautics and Space Administration — The Improved Stratospheric and Mesospheric Sounder (ISAMS) Level 3AT data product consists of daily, 65.536 second interval time-ordered vertical profiles of...

  6. Hurricane and Severe Storm Sentinel (HS3) Scanning High-Resolution Interferometer Sounder (S-HIS) V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The Hurricane and Severe Storm Sentinel (HS3) Scanning High-Resolution Interferometer Sounder (S-HIS) measures emitted thermal radiances that are used to obtain...

  7. 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...

  8. Implementing earth observation and advanced satellite based atmospheric sounders for water resource and climate modelling

    DEFF Research Database (Denmark)

    Boegh, E.; Dellwik, Ebba; Hahmann, Andrea N.

    for effective land surface representation in water resource modeling” (2009- 2012). The purpose of the new research project is to develop remote sensing based model tools capable of quantifying the relative effects of site-specific land use change and climate variability at different spatial scales......This paper discusses preliminary remote sensing (MODIS) based hydrological modelling results for the Danish island Sjælland (7330 km2) in relation to project objectives and methodologies of a new research project “Implementing Earth observation and advanced satellite based atmospheric sounders....... For this purpose, a) internal catchment processes will be studied using a Distributed Temperature Sensing (DTS) system, b) Earth observations will be used to upscale from field to regional scales, and c) at the largest scale, satellite based atmospheric sounders and meso-scale climate modelling will be used...

  9. Spectral Interpretation of Radio Sounder-Stimulated Magnetospheric Plasma Resonances in Terms of Kappa Distributions

    Science.gov (United States)

    Benson, Robert F.; Vinas, Adolfo, F.; Fainberg, Joseph; Osherovich, Vladimir A.; Purser, Carola M.; Galkin, Ivan A.; Reinisch, Bodo W.

    2011-01-01

    Magnetosphere sounders stimulate plasma resonances between the harmonics of the electron cyclotron frequency and above the upper-hybrid frequency. More than three decades ago they were recognized as equivalent to ionospheric topside-sounder-stimulated resonances, designated as Qn resonances a decade earlier, with one important difference: the magnetospheric Qn frequencies often indicated that the background electron-velocity distribution was non-Maxwellian. Interpretations based on bi-Maxwellian and kappa distributions have been proposed. Here we expand on the latter, which requires fewer free parameters, by comparing kappa-derived Qn frequencies with observations from the Radio Plasma Imager on the Imager for Magnetopause-to-Aurora Global Exploration (IMAGE) satellite.

  10. 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.

  11. A review of results of the international ionospheric Doppler sounder network

    Science.gov (United States)

    Laštovička, Jan; Chum, Jaroslav

    2017-10-01

    This paper summarizes main recent results reached by the Czech-lead international network of ionospheric Doppler shift sounders. The network consists of Doppler sounders in the western half of Czechia (5 measuring paths, 3 frequencies with central receivers in Prague), northern Taiwan (3 transmitters, two separated receivers, 1 frequency), and two similar systems (3 measuring paths with 1 receiver and 1 frequency) in Tucuman (north-western Argentina) and Hermanus (the southernmost South Africa). Main areas of research have been: (1) propagation of gravity waves; (2) ionospheric effects of earthquakes; (3) low latitude/equatorial phenomena; (4) ionospheric response to strong meteorological phenomena; (5) effects of solar flares, geomagnetic activity and geomagnetic micropulsations. Main results: (1) Theoretically expected dominance of gravity wave propagation against wind has been confirmed. (2) Impact of a train of seismic waves (P, S, SS, Rayleigh) generated by the Tohoku 2011 M9.0 earthquake was registered in the ionosphere over the Czech Republic as long-period infrasound at the distance of about 9000 km from epicenter. (3) Analysis of ionospheric infrasound excited by the Nepal 2015 M7.8 earthquake observed by the Czech and Taiwan Doppler sounders showed that the intensity of ionospheric signal is significantly height and latitude dependent. Air/plasma compression has to be considered to compute air particle velocities from the observed Doppler shift. (4) Nonlinear effects result in formation of N-shaped pulse disturbance in the upper atmosphere/ionosphere above strong earthquakes as was documented by the example of the M8.3 Illapel 2016 earthquake. (5) Spread F structures observed by Doppler sounders in Tucuman and Taiwan (both under the crest of equatorial ionization anomaly) provide results consistent with S4 scintillation data and with previous optical, GPS and satellite measurements. (6) Short period gravity waves and rarely infrasound are observed in the

  12. Nonlinearities in Microwave Superconductivity

    OpenAIRE

    Ledenyov, Dimitri O.; Ledenyov, Viktor O.

    2012-01-01

    The research is focused on the modeling of nonlinear properties of High Temperature Superconducting (HTS) thin films, using Bardeen, Cooper, Schrieffer and Lumped Element Circuit theories, with purpose to enhance microwave power handling capabilities of microwave filters and optimize design of microwave circuits in micro- and nano- electronics.

  13. On the remote sensing of cloud properties from satellite infrared sounder data

    Science.gov (United States)

    Yeh, H. Y. M.

    1984-01-01

    A method for remote sensing of cloud parameters by using infrared sounder data has been developed on the basis of the parameterized infrared transfer equation applicable to cloudy atmospheres. The method is utilized for the retrieval of the cloud height, amount, and emissivity in 11 micro m region. Numerical analyses and retrieval experiments have been carried out by utilizing the synthetic sounder data for the theoretical study. The sensitivity of the numerical procedures to the measurement and instrument errors are also examined. The retrieved results are physically discussed and numerically compared with the model atmospheres. Comparisons reveal that the recovered cloud parameters agree reasonably well with the pre-assumed values. However, for cases when relatively thin clouds and/or small cloud fractional cover within a field of view are present, the recovered cloud parameters show considerable fluctuations. Experiments on the proposed algorithm are carried out utilizing High Resolution Infrared Sounder (HIRS/2) data of NOAA 6 and TIROS-N. Results of experiments show reasonably good comparisons with the surface reports and GOES satellite images.

  14. Inter-Comparison of GOES-8 Imager and Sounder Skin Temperature Retrievals

    Science.gov (United States)

    Haines, Stephanie L.; Suggs, Ronnie J.; Jedlovec, Gary J.; Arnold, James E. (Technical Monitor)

    2001-01-01

    Skin temperature (ST) retrievals derived from geostationary satellite observations have both high temporal and spatial resolutions and are therefore useful for applications such as assimilation into mesoscale forecast models, nowcasting, and diagnostic studies. Our retrieval method uses a Physical Split Window technique requiring at least two channels within the longwave infrared window. On current GOES satellites, including GOES-11, there are two Imager channels within the required spectral interval. However, beginning with the GOES-M satellite the 12-um channel will be removed, leaving only one longwave channel. The Sounder instrument will continue to have three channels within the longwave window, and therefore ST retrievals will be derived from Sounder measurements. This research compares retrievals from the two instruments and evaluates the effects of the spatial resolution and sensor calibration differences on the retrievals. Both Imager and Sounder retrievals are compared to ground-truth data to evaluate the overall accuracy of the technique. An analysis of GOES-8 and GOES-11 intercomparisons is also presented.

  15. Atmospheric inertia-gravity waves retrieved from level-2 data of the satellite microwave limb sounder Aura/MLS

    Directory of Open Access Journals (Sweden)

    K. Hocke

    2016-09-01

    Full Text Available The temperature profiles of the satellite experiment Aura/MLS are horizontally spaced by 1.5° or 165 km along the satellite orbit. These level-2 data contain valuable information about horizontal fluctuations in temperature, which are mainly induced by inertia-gravity waves. Wave periods of 2–12 h, horizontal wavelengths of 200–1500 km, and vertical wavelengths of 6–30 km efficiently contribute to the standard deviation of the horizontal temperature fluctuations. The study retrieves and discusses the global distributions of inertia-gravity waves in the stratosphere and mesosphere during July 2015 and January 2016. We find many patterns that were previously present in data of TIMED/SABER, Aura/HIRDLS, and ECMWF analysis. However, it seems that Aura/MLS achieves a higher vertical resolution in the gravity wave maps since the maps are derived from the analysis of horizontal fluctuations along the orbit of the sounding volume. The zonal mean of the inertia-gravity wave distribution shows vertical modulations with scales of 10–20 km. Enhanced wave amplitudes occur in regions of increased zonal wind or in the vicinity of strong wind gradients. Further, we find a banana-like shape of enhanced inertia-gravity waves above the Andes in the winter mesosphere. We find areas of enhanced inertia-gravity wave activity above tropical deep convection zones at 100 hPa (z ∼ 13 km. Finally, we study the temporal evolution of inertia-gravity wave activity at 100 hPa in the African longitude sector from December 2015 to February 2016.

  16. 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.

  17. High brightness microwave lamp

    Science.gov (United States)

    Kirkpatrick, Douglas A.; Dolan, James T.; MacLennan, Donald A.; Turner, Brian P.; Simpson, James E.

    2003-09-09

    An electrodeless microwave discharge lamp includes a source of microwave energy, a microwave cavity, a structure configured to transmit the microwave energy from the source to the microwave cavity, a bulb disposed within the microwave cavity, the bulb including a discharge forming fill which emits light when excited by the microwave energy, and a reflector disposed within the microwave cavity, wherein the reflector defines a reflective cavity which encompasses the bulb within its volume and has an inside surface area which is sufficiently less than an inside surface area of the microwave cavity. A portion of the reflector may define a light emitting aperture which extends from a position closely spaced to the bulb to a light transmissive end of the microwave cavity. Preferably, at least a portion of the reflector is spaced from a wall of the microwave cavity. The lamp may be substantially sealed from environmental contamination. The cavity may include a dielectric material is a sufficient amount to require a reduction in the size of the cavity to support the desired resonant mode.

  18. 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.

  19. 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...

  20. Magnetoelectrical control of nonreciprocal microwave response in a multiferroic helimagnet

    Science.gov (United States)

    Iguchi, Y.; Nii, Y.; Onose, Y.

    2017-05-01

    The control of physical properties by external fields is essential in many contemporary technologies. For example, conductance can be controlled by a gate electric field in a field effect transistor, which is a main component of integrated circuits. Optical phenomena induced by an electric field such as electroluminescence and electrochromism are useful for display and other technologies. Control of microwave propagation is also important for future wireless communication technology. Microwave properties in solids are dominated mostly by magnetic excitations, which cannot be easily controlled by an electric field. One solution to this problem is to use magnetically induced ferroelectrics (multiferroics). Here we show that microwave nonreciprocity, that is, different refractive indices for microwaves propagating in opposite directions, could be reversed by an external electric field in a multiferroic helimagnet Ba2Mg2Fe12O22. This approach offers an avenue for the electrical control of microwave properties.

  1. 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...

  2. Experiences With an Optimal Estimation Algorithm for Surface and Atmospheric Parameter Retrieval From Passive Microwave Data in the Arctic

    DEFF Research Database (Denmark)

    Scarlat, Raul Cristian; Heygster, Georg; Pedersen, Leif Toudal

    2017-01-01

    the brightness temperatures observed by a passive microwave radiometer. The retrieval method inverts the forward model and produces ensembles of the seven parameters, wind speed, integrated water vapor, liquid water path, sea and ice temperature, sea ice concentration and multiyear ice fraction. The method......We present experiences in using an integrated retrieval method for atmospheric and surface parameters in the Arctic using passive microwave data from the AMSR-E radiometer. The core of the method is a forward model which can ingest bulk data for seven geophysical parameters to reproduce...... compared with the Arctic Systems Reanalysis model data as well as columnar water vapor retrieved from satellite microwave sounders and the Remote Sensing Systems AMSR-E ocean retrieval product in order to determine the feasibility of using the same setup over pure surface with 100% and 0% sea ice cover...

  3. 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.

  4. Using your microwave oven. Lesson 6, Microwave oven management

    OpenAIRE

    Woodard, Janice Emelie, 1929-

    1984-01-01

    Discusses cooking and reheating foods in microwave ovens, and adapting conventional recipes for the microwave. Revised Includes the publication: Adapting conventional recipes to microwave cooking : fact sheet 84 by Janice Woodard, Rebecca Lovingood, R.H. Trice.

  5. Assimilating synthetic hyperspectral sounder temperature and humidity retrievals to improve severe weather forecasts

    Science.gov (United States)

    Jones, Thomas A.; Koch, Steven; Li, Zhenglong

    2017-04-01

    Assimilation of hyperspectral sounder data into numerical weather prediction (NWP) models has proven vital to generating accurate model analyses of tropospheric temperature and humidity where few conventional observations exist. Applications to storm-scale models are limited since the low temporal resolution provided by polar orbiting sensors cannot adequately sample rapidly changing environments associated with high impact weather events. To address this limitation, hyperspectral sounders have been proposed for geostationary orbiting satellites, but these have yet to be built and launched in part due to much higher engineering costs and a lack of a definite requirement for the data. This study uses an Observation System Simulation Experiment (OSSE) approach to simulate temperature and humidity profiles from a hypothetical geostationary-based sounder from a nature run of a high impact weather event on 20 May 2013. The simulated observations are then assimilated using an ensemble adjustment Kalman filter approach, testing both hourly and 15 minute cycling to determine their relative effectiveness at improving the near storm environment. Results indicate that assimilating both temperature and humidity profiles reduced mid-tropospheric both mean and standard deviation of analysis and forecast errors compared to assimilating conventional observations alone. The 15 minute cycling generally produced the lowest errors while also generating the best 2-4 hour updraft helicity forecasts of ongoing convection. This study indicates the potential for significant improvement in short-term forecasting of severe storms from the assimilation of hyperspectral geostationary satellite data. However, more studies are required using improved OSSE designs encompassing multiple storm environments and additional observation types such as radar reflectivity to fully define the effectiveness of assimilating geostationary hyperspectral observations for high impact weather forecasting

  6. Preliminary validation of the refractivity from the new radio occultation sounder GNOS/FY-3C

    Science.gov (United States)

    Liao, Mi; Zhang, Peng; Yang, Guang-Lin; Bi, Yan-Meng; Liu, Yan; Bai, Wei-Hua; Meng, Xiang-Guang; Du, Qi-Fei; Sun, Yue-Qiang

    2016-03-01

    As a new member of the space-based radio occultation sounders, the GNOS (Global Navigation Satellite System Occultation Sounder) mounted on Fengyun-3C (FY-3C) has been carrying out atmospheric sounding since 23 September 2013. GNOS takes approximately 800 daily measurements using GPS (Global Positioning System) and Chinese BDS (BeiDou navigation satellite) signals. In this work, the atmospheric refractivity profiles from GNOS were compared with the ones obtained from the co-located ECMWF (European Centre for Medium-Range Weather Forecasts) reanalysis. The mean bias of the refractivity obtained through GNOS GPS (BDS) was found to be approximately -0.09 % (-0.04 %) from the near surface to up to 46 km. While the average standard deviation was approximately 1.81 % (1.26 %), it was as low as 0.75 % (0.53 %) in the range of 5-25 km, where best sounding results are usually achieved. Further, COSMIC (Constellation Observing System for Meteorology, Ionosphere and Climate) and MetOp/ GRAS (GNSS Receiver for Atmospheric Sounding) radio occultation data were compared with the ECMWF reanalysis; the results thus obtained could be used as reference data for GNOS. Our results showed that GNOS/FY-3C meets the design requirements in terms of accuracy and precision of the sounder. It possesses a sounding capability similar to COSMIC and MetOp/GRAS in the vertical range of 0-30 km, though it needs further improvement above 30 km. Overall, it provides a new data source for the global numerical weather prediction (NWP) community.

  7. 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

  8. Intracity Quantum Communication via Thermal Microwave Networks

    Science.gov (United States)

    Xiang, Ze-Liang; Zhang, Mengzhen; Jiang, Liang; Rabl, Peter

    2017-01-01

    Communication over proven-secure quantum channels is potentially one of the most wide-ranging applications of currently developed quantum technologies. It is generally envisioned that in future quantum networks, separated nodes containing stationary solid-state or atomic qubits are connected via the exchange of optical photons over large distances. In this work, we explore an intriguing alternative for quantum communication via all-microwave networks. To make this possible, we describe a general protocol for sending quantum states through thermal channels, even when the number of thermal photons in the channel is much larger than 1. The protocol can be implemented with state-of-the-art superconducting circuits and enables the transfer of quantum states over distances of about 100 m via microwave transmission lines cooled to only T =4 K . This opens up new possibilities for quantum communication within and across buildings and, consequently, for the implementation of intracity quantum networks based on microwave technology only.

  9. Direction-of-Arrival Analysis of Airborne Ice Depth Sounder Data

    DEFF Research Database (Denmark)

    Nielsen, Ulrik; Yan, Jie-Bang; Gogineni, Sivaprasad

    2017-01-01

    In this paper, we analyze the direction-of arrival(DOA) of the ice-sheet data collected over Jakobshavn Glacier with the airborne Multichannel Radar Depth Sounder (MCRDS) during the 2006 field season. We extracted weak ice–bed echoes buried in signals scattered by the rough surface of the fast......-flowing Jakobshavn Glacier by analyzing the DOA of signals received with a five-element receive-antenna array. This allowed us to obtain ice thickness information, which is a key parameter when generating bed topography of glaciers. We also estimated ice–bed roughness and bed slope from the combined analysis...

  10. Phase Change Material for Temperature Control of Imager or Sounder on GOES Type Satellites in GEO

    Science.gov (United States)

    Choi, Michael K.

    2014-01-01

    This paper uses phase change material (PCM) in the scan cavity of an imager or sounder on satellites in geostationary orbit (GEO) to maintain the telescope temperature stable. When sunlight enters the scan aperture, solar heating causes the PCM to melt. When sunlight stops entering the scan aperture, the PCM releases the thermal energy stored to keep the components in the telescope warm. It has no moving parts or bimetallic springs. It reduces heater power required to make up the heat lost by radiation to space through the aperture. It is an attractive thermal control option to a radiator with a louver and a sunshade.

  11. Laser Sounder for Global Measurement of CO2 Concentrations in the Troposphere from Space: Progress

    Science.gov (United States)

    Abshire, J. B.; Krainak, M.; Riris, H. J.; Sun, X.; Riris, H.; Andrews, A. E.; Collatz, J.

    2004-01-01

    We describe progress toward developing a laser-based technique for the remote measurement of the tropospheric CO2 concentrations from orbit. Our goal is to demonstrate a lidar technique and instrument technology that will permit measurements of the CO2 column abundance in the lower troposphere from aircraft at the few ppm level, with a capability of scaling to permit global CO2 measurements from orbit. Accurate measurements of the tropospheric CO2 mixing ratio from space are challenging due to the many potential error sources. These include possible interference from other trace gas species, the effects of temperature, clouds, aerosols & turbulence in the path, changes in surface reflectivity, and variability in dry air density caused by changes in atmospheric pressure, water vapor and topographic height. Some potential instrumental errors include frequency drifts in the transmitter, small transmission and sensitivity drifts in the instrument. High signal-to-noise ratios and measurement stability are needed for mixing ratio estimates at the few ppm level. We have been developing a laser sounder approach as a candidate for a future space mission. It utilizes multiple different laser transmitters to permit simultaneous measurement of CO2 and O2 extinction, and aerosol backscatter in the same measurement path. It directs the narrow co-aligned laser beams from the instrument's fiber lasers toward nadir, and measures the energy of the strong laser echoes reflected from the Earth's land and water surfaces. During the measurement its narrow linewidth lasers are rapidly tuned on- and off- selected CO2 line near 1572 nm and an O2 absorption line near 770 nm. The receiver measures the energies of the laser echoes from the surface and any clouds and aerosols in the path with photon counting detectors. Ratioing the on- to off-line echo pulse energies for each gas permits the column extinction and column densities of CO2 and O2 to be estimated simultaneously via the

  12. Advanced microwave processing concepts

    Energy Technology Data Exchange (ETDEWEB)

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

    1997-04-01

    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 polymeric materials. The variable frequency microwave furnace, whose initial conception and design was funded by the AIM Materials Program, allows the authors, 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 various thermoset resins will be studied because it holds the potential of in-situ curing of continuous-fiber composites for strong, lightweight components or in-situ curing of adhesives, including metal-to-metal. Microwave heating can shorten curing times, provided issues of scaleup, uniformity, and thermal management can be adequately addressed.

  13. 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

  14. Microwave Enhanced Freeze Drying of Solid Waste Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Development of technology for Microwave Enhanced Freeze Drying of Solid Waste (MEFDSW) is proposed. The present state of the art for solid waste stabilization using...

  15. Radar Sounder

    Science.gov (United States)

    1988-09-01

    free" measurements on the same or previous orbits. The Scatterometer is an integral part of the radar. The proposed system which is currently called...Right Arrays SATELLITE ( I ATOMOS PHERE/ SWATHWI DTH Figure 3.1.1 Metrad Coverage 18 4 05. 4 1-4 " -u a . .4 c4 641 C Ov31 N -4 a ~ U . - I.44m 41 44...application is not a study objective, but could be considered as part of an experimental program utilizing scatterometer, radiometer and high resolution

  16. Global Observations of Mid-Tropospheric Carbon Dioxide Using the AIRS Sounder on EOS-AQUA

    Science.gov (United States)

    Strow, L. L.; Hannon, S.

    2005-12-01

    The Atmospheric Infrared Sounder (AIRS) has been operating continuously for more than 3 years, providing a large record of hyperspectral radiances throughout the mid-infrared. We have generated a subset of all AIRS radiances for clear, ocean fields-of-view for the purposes of validation of both the sensor and the radiative transfer algorithm used for temperature and humidity retrievals. Radiance bias comparisons between observed radiances, and those computed from both (1) radiosondes launched coincident with AIRS, and (2) ECMWF analysis/forecast fields exhibit variations with both latitude and time due to variable carbon dioxide. We present here zonally-averaged (ocean only) retrievals of mid-tropospheric carbon dioxide derived from the biases between AIRS observations and radiances computed from ECMWF. The time and latitude dependence of monthly averages of the retrieved zonal carbon dioxide amounts exhibit behavior close to the NOAA/CMDL global carbon dioxide climatologies. Long-term satellite observations of global carbon dioxide with operational hyperspectral sounders should be feasible and provide an important contribution to our understanding of carbon dioxide emissions.

  17. Acoustic systems (split beam echo sounder to determine abundance of fish in marine fisheries

    Directory of Open Access Journals (Sweden)

    Muhammad Zainuddin Lubis

    2017-03-01

    Full Text Available Acoustic waves are transmitted into the subsurface ocean will experience scattering (scattering caused by marine organisms, material distributed in the ocean, the structure is not homogeneous in seawater, as well as reflections from the surface and the seabed. Estimation of fish stocks in the waters wide as in Indonesia have a lot of them are using the acoustic method. The acoustic method has high speed in predicting the size of fish stocks so as to allow acquiring data in real time, accurate and high speed so as to contribute fairly high for the provision of data and information of fishery resources.  Split beam echo sounder comprises two aspects, and a transducer. The first aspect is the high-resolution color display for displaying echogram at some observations and also serves as a controller in the operation of the echo sounder. The second aspect is transceiver consisting of transmitter and receiver. The Echosounder divided beam first inserted into the ES 3800 by SIMRAD beginning of the 1980s and in 1985 was introduced to fishermen in Japan as a tool for catching up. Split beam transducer is divided into four quadrants.  Factors that contribute affect the value of Target Strength (TS fish Strength target can generally be influenced by three factors: a target factor itself, environmental factors, and factors acoustic instrument. Factors include the size of the target, the anatomy of fish, swim bladder, the behavior of orientation.

  18. Counter electrojet features in the Brazilian sector: simultaneous observation by radar, digital sounder and magnetometers

    Directory of Open Access Journals (Sweden)

    C. M. Denardini

    2009-04-01

    Full Text Available In the present work we show new results regarding equatorial counter electrojet (CEJ events in the Brazilian sector, based on the RESCO radar, two set of fluxgate magnetometer systems and a digital sounder. RESCO radar is a 50 MHz backscatter coherent radar installed in 1998 at São Luís (SLZ, 2.33° S, 44.60° W, an equatorial site. The Digital sounder routinely monitors the electron density profile at the radar site. The magnetometer systems are fluxgate-type installed at SLZ and Eusébio (EUS, 03.89° S, 38.44° W. From the difference between the horizontal component of magnetic field at SLZ station and the same component at EUS (EEJ ground strength several cases of westward morning electrojet and its normal inversion to the eastward equatorial electrojet (EEJ have been observed. Also, the EEJ ground strength has shown some cases of CEJ events, which been detected with the RESCO radar too. Detection of these events were investigated with respect to their time and height of occurrence, correlation with sporadic E (Es layers at the same time, and their spectral characteristics as well as the radar echo power intensity.

  19. Preliminary validation of refractivity from a new radio occultation sounder GNOS/FY-3C

    Science.gov (United States)

    Liao, M.; Zhang, P.; Yang, G. L.; Bi, Y. M.; Liu, Y.; Bai, W. H.; Meng, X. G.; Du, Q. F.; Sun, Y. Q.

    2015-09-01

    As a new member of space-based radio occultation sounder, the GNOS (Global Navigation Satellite System Occultation Sounder) mounted on FY-3C has been carrying out the atmospheric sounding since 23 September 2013. GNOS takes a daily measurement up to 800 times with GPS (Global Position System) and Chinese BDS (BeiDou navigation satellite) signals. The refractivity profiles from GNOS are compared with the co-located ECMWF (European Centre for Medium-Range Weather Forecasts) analyses in this paper. Bias and standard deviation have being calculated as the function of altitude. The mean bias is about 0.2 % from the near surface to 35 km. The average standard deviation is within 2 % while it is down to about 1 % in the range 5-30 km where best soundings are usually made. To evaluate the performance of GNOS, COSMIC (Constellation Observing System for Meteorology, Ionosphere and Climate) and GRAS/METOP-A (GNSS Receiver for Atmospheric Sounding) data are also compared to ECMWF analyses as the reference. The results show that GNOS/FY-3C meets the requirements of the design well. It possesses a sounding capability similar to COSMIC and GRAS in the vertical range of 0-30 km, though it needs improvement in higher altitude. Generally, it provides a new data source for global NWP (numerical weather prediction) community.

  20. Microwave hydrology: A trilogy

    Science.gov (United States)

    Stacey, J. M.; Johnston, E. J.; Girard, M. A.; Regusters, H. A.

    1985-01-01

    Microwave hydrology, as the term in construed in this trilogy, deals with the investigation of important hydrological features on the Earth's surface as they are remotely, and passively, sensed by orbiting microwave receivers. Microwave wavelengths penetrate clouds, foliage, ground cover, and soil, in varying degrees, and reveal the occurrence of standing liquid water on and beneath the surface. The manifestation of liquid water appearing on or near the surface is reported by a microwave receiver as a signal with a low flux level, or, equivalently, a cold temperature. Actually, the surface of the liquid water reflects the low flux level from the cosmic background into the input terminals of the receiver. This trilogy describes and shows by microwave flux images: the hydrological features that sustain Lake Baykal as an extraordinary freshwater resource; manifestations of subsurface water in Iran; and the major water features of the Congo Basin, a rain forest.

  1. 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.

  2. Practical investigations on monolithic integrated microwave filters

    OpenAIRE

    Stephan, R; Möhring, J.

    1996-01-01

    Filters at microwave frequencies today normally are built in hybrid technology. In this paper principles for the monolit­hic integration of frequency selective structures without any external component are investigated. Monolithic Filters at frequencies about 10 GHz based on lumped LC-structures and about 30 GHz in coplanar waveguide technology are presented. Both filter concepts need active components to compensate the insertion loss of the filters. All components are interconnected by copla...

  3. The High Altitude MMIC Sounding Radiometer on the GLOBAL HAWK: From Technology Development to Science Discovery

    Science.gov (United States)

    Brown, Shannon; Denning, Richard; Lambrigtsen, Bjorn; Lim, Boon; Tanabe, Jordan; Tanner, Alan

    2013-01-01

    This paper presents results from the High Altitude MMIC Sounding Radiometer (HAMSR) during three recent field campaigns on the Global Hawk Unmanned Ariel Vehicles (UAV), focusing on the enabling technology that led to unprecedented observations of significant weather phenomenon, such as thermodynamic evolution of the tropical cyclone core during rapid intensification and the high resolution three dimensional mapping of several atmospheric river events. HAMSR is a 25 channel cross-track scanning microwave sounder with channels near the 60 and 118 GHz oxygen lines and the 183 GHz water vapor line. HAMSR was originally designed and built at the Jet Propulsion Laboratory as a technology demonstrator in 1998. Subsequent to this, HAMSR participated in three NASA hurricane field campaigns, CAMEX-4, TCSP and NAMMA. Beginning in 2008, HAMSR was extensively upgraded to deploy on the NASA Global Hawk (GH) platform and serve as an asset to the NASA sub-orbital program. HAMSR has participated on the Global Hawk during the 2010 Genesis and Rapid Intensification (GRIP) campaign, the 2011 Winter Storms and Atmospheric Rivers (WISPAR) campaign and is currently participating in the NASA Ventures Hurricane and Severe Storm Sentinel (HS3) campaign (2011-2015).

  4. 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.

  5. Microwave plasma torch for processing hydrocarbon gases

    Directory of Open Access Journals (Sweden)

    Alex G. Zherlitsyn

    2016-03-01

    Full Text Available We designed and developed an ultrahigh-frequency (microwave plasma torch with a combined (nitrogen, methane plasma-forming environment, and microwave output of up to 2 kW, continuously. We demonstrate the possibility of using it in order to process natural and associated petroleum (APG gas into valuable products (hydrogen and carbon nanomaterial CNM with up to 70% efficiency. Based on the developed microwave plasma torch, we developed an apparatus capable of converting hydrocarbon feedstock at a capacity of 50 g/h yielding CNM and hydrogen of up to 70 vol. %. In its mobile small-tonnage version, this technology can be used on gas-condensate fields.

  6. 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

  7. Microwave coupler and method

    Science.gov (United States)

    Holcombe, C. E.

    1984-11-01

    The present invention is directed to a microwave coupler for enhancing the heating or metallurgical treatment of materials within a cold-wall, rapidly heated cavity as provided by a microwave furnace. The coupling material of the present invention is an alpha-rhombohedral-boron-derivative-structure material such as boron carbide or boron silicide which can be appropriately positioned as a susceptor within the furnace to heat other material or be in powder particulate form so that composites and structures of boron carbide such as cutting tools, grinding wheels and the like can be rapidly and efficiently formed within microwave furnaces.

  8. 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

  9. 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.

  10. Unlocking Potentials of Microwaves for Food Safety and Quality

    Science.gov (United States)

    Tang, Juming

    2015-01-01

    Microwave is an effective means to deliver energy to food through polymeric package materials, offering potential for developing short-time in-package sterilization and pasteurization processes. The complex physics related to microwave propagation and microwave heating require special attention to the design of process systems and development of thermal processes in compliance with regulatory requirements for food safety. This article describes the basic microwave properties relevant to heating uniformity and system design, and provides a historical overview on the development of microwave-assisted thermal sterilization (MATS) and pasteurization systems in research laboratories and used in food plants. It presents recent activities on the development of 915 MHz single-mode MATS technology, the procedures leading to regulatory acceptance, and sensory results of the processed products. The article discusses needs for further efforts to bridge remaining knowledge gaps and facilitate transfer of academic research to industrial implementation. PMID:26242920

  11. Single Microwave Photon Detection with a Trapped Electron

    Directory of Open Access Journals (Sweden)

    April Cridland

    2016-11-01

    Full Text Available We investigate theoretically the use of an electron in a Penning trap as a detector of single microwave photons. At the University of Sussex we are developing a chip Penning trap technology, designed to be integrated within quantum circuits. Microwave photons are guided into the trap and interact with the electron’s quantum cyclotron motion. This is an electric dipole transition, where the near field of the microwave radiation induces quantum jumps of the cyclotron harmonic oscillator. The quantum jumps can be monitored using the continuous Stern-Gerlach effect, providing the quantum non demolition signal of the microwave quanta. We calculate the quantum efficiency of photon detection and discuss the main features and technical challenges for the trapped electron as a quantum microwave sensor.

  12. ESA'S POLarimetric Airborne Radar Ice Sounder (POLARIS): design and first results

    DEFF Research Database (Denmark)

    Dall, Jørgen; Kristensen, Steen Savstrup; Krozer, Viktor

    2010-01-01

    The Technical University of Denmark has developed and tested a P-band ice sounding radar for European Space Agency (ESA). With the recent by the International Telecommunication Union (ITU) allocation of a radar band at 435 MHz, increased interest in space-based sounding of the Earth s ice caps has...... been encountered. ESA s POLarimetric Airborne Radar Ice Sounder (POLARIS) is intended to provide a better understanding of P-band scattering and propagation through ice sheets and to verify novel surface clutter suppression techniques in preparation for a potential space-based ice sounding mission......-of-concept campaign was conducted in Greenland. This study outlines the design and implementation of the system, and based on first results it is concluded that in the central dry snow zone of Greenland, POLARIS can resolve shallow and deep internal ice layers, penetrate the thickest ice encountered and detect...

  13. Laser Atmospheric Wind Sounder (LAWS) phase 1. Volume 3: Project cost estimates

    Science.gov (United States)

    1990-01-01

    The laser atmospheric wind sounder (LAWS) cost modeling activities were initiated in phase 1 to establish the ground rules and cost model that would apply to both phase 1 and phase 2 cost analyses. The primary emphasis in phase 1 was development of a cost model for a LAWS instrument for the Japanese Polar Orbiting Platform (JPOP). However, the Space Station application was also addressed in this model, and elements were included, where necessary, to account for Space Station unique items. The cost model presented in the following sections defines the framework for all LAWS cost modeling. The model is consistent with currently available detail, and can be extended to account for greater detail as the project definition progresses.

  14. The Laser Atmospheric Wind Sounder (LAWS) phase 2 preliminary laser design

    Science.gov (United States)

    Lawrence, T. Rhidian; Pindroh, Albert L.; Bowers, Mark S.; Dehart, Terence E.; McDonald, Kenneth F.; Cousins, Ananda; Moody, Stephen E.

    1992-07-01

    The requirements for the Laser Atmospheric Wind Sounder (LAWS) were determined from system considerations and are summarized in tabular form. The laser subsystem provides for the generation and frequency control of two beams, the transmit high power and local oscillator beams, which are delivered to the optical and receiver subsystems, respectively. In our baseline approach, the excitation of the gain section is achieved by a self-sustaining uv-(corona) preionized discharge. Gas is recirculated within the laser loop using a transverse flow fan. An intra-flow-loop heat exchanger, catalyst monolith, and acoustic attenuators condition the gas to ensure uniform energy output and high beam quality during high pulse repetition rate operation. The baseline LAWS laser pulse temporal profile as calculated by in-house laser codes is given in graphical form.

  15. Navigation Signal Disturbances by Multipath Propagation - Scaled Measurements with a Universal Channel Sounder Architecture

    Science.gov (United States)

    Geise, Robert; Neubauer, Bjoern; Zimmer, Georg

    2015-11-01

    The performance of navigation systems is always reduced by unwanted multipath propagation. This is especially of practical importance for airborne navigation systems like the instrument landing system (ILS) or the VHF omni directional radio range (VOR). Nevertheless, the quantitative analysis of corresponding, potentially harmful multipath propagation disturbances is very difficult due to the large parameter space. Experimentally difficulties arise due to very expensive, real scale measurement campaigns and numerical simulation techniques still have shortcomings which are briefly discussed. In this contribution a new universal approach is introduced on how to measure very flexibly multipath propagation effects for arbitrary navigation systems using a channel sounder architecture in a scaled measurement environment. Two relevant scenarios of multipath propagation and the impact on navigation signals are presented. The first describes disturbances of the ILS due to large taxiing aircraft. The other example shows the influence of rotating wind turbines on the VOR.

  16. Analysis of high altitude clouds in the martian atmosphere based on Mars Climate Sounder observations

    Science.gov (United States)

    Puspitarini, L.; Määttänen, A.; Fouchet, T.; Kleinboehl, A.; Kass, D. M.; Schofield, J. T.

    2016-11-01

    High altitude clouds have been observed in the Martian atmosphere. However, their properties still remain to be characterized. Mars Climate Sounder (MCS) aboard Mars Reconnaissance Orbiter (MRO) is an instrument that measures radiances in the thermal infrared, both in limb and nadir views. It allows us to retrieve vertical profiles of radiance, temperature and aerosols. Using the MCS data and radiative transfer model coupled with an automated inversion routine, we can investigate the chemical composition of the high altitude clouds. We will present the first results on the properties of the clouds. CO2 ice is the best candidate to be the main component of some high altitude clouds due to the most similar spectral variation compared to water ice or dust, in agreement with previous studies. Using cloud composition of contaminated CO2 ice (dust core surrounded by CO2 ice) might improve the fitting result, but further study is needed.

  17. NOVEL SNOW DEPTH RETRIEVAL METHOD USING TIME SERIES SSMI PASSIVE MICROWAVE IMAGERY

    Directory of Open Access Journals (Sweden)

    Z. Nikraftar

    2016-06-01

    Full Text Available The Special Sensor Microwave Imager (SSM/I and the Special Sensor Microwave Imager Sounder (SSM/IS are satellites that work in passive microwave range. The SSM/I has capability to measure geophysical parameters which these parameters are key to investigate the climate and hydrology condition in the world. In this research the SSMI passive microwave data is used to study the feasibility of monitoring snow depth during snowfall month from 2010 to 2015 using an algorithm in conjunction with ground depth measured at meteorological stations of the National Centre for Environmental Information (NCEI. The previous procedures for snow depth retrieval algorithms uses only one or two passive bands for modelling snow depth. This study enable us to use of a nonlinear multidimensional regression algorithm which incorporates all channels and their related weighting coefficients for each band. Higher value of these coefficients are indicator of the importance of each band in the regression model. All channels and their combination were used in support of the vector algorithm combined with genetic algorithm (GA for feature selection to estimate snow depth. The results were compared with those algorithms developed by recent researchers and the results clearly shows the superiority of proposed method (R2 = 0.82 and RMSE = 6.3 cm.

  18. Observation of Moon Jellyfish Spatial Distribution Using a Scientific Echo Sounder and Underwater Camera

    Science.gov (United States)

    Mano, T.; Guo, X.; Fujii, N.; Yoshie, N.; Takeoka, H.

    2016-02-01

    Jellyfishes often form dense aggregation that causes a variety of social problems such as clogging seawater intake of power plant, breaking fisheries net and more. Understanding on jellyfish aggregation is not sufficient due to the difficulty of observation on this phenomenon. In this study, high-resolution observations using scientific echo sounder and underwater camera were carried out to reveal the fine structure of moon jellyfish distribution in a 3D space, as well as its abundance and temporal variation. In addition, water temperature, salinity and current speed were also measured for inferring formation mechanisms of jellyfish aggregation. The field observations with a target on moon jellyfish were carried out in August 2013 and August 2014, in a semi-enclosed bay in Japan. The ship equipped with scientific echo sounder was cruised over the entire bay to reveal the distribution and the form of the moon jellyfish aggregation. In August 2013, the jellyfish aggregations present a high density (maximum: 70 ind. /m3) and their outline shows spherical or zonal shape with a hollow structure. In August 2014, the jellyfish aggregations present a low density (maximum: 20 ind./m3) and the jellyfishes distributed in a layer structure over a wide area. The depth of jellyfish aggregation was consistent with thermocline. During three days of observations in 2014, the average population density of jellyfish reduced by one-tenth, showing a possibility that the jellyfish abundance in a bay may vary significantly in a short timescale of several days. Not only the active swimming of jellyfishes but also the ambient flow field associated with internal waves or Langmuir circulation may contribute to the jellyfish aggregations. In order to clarify the mechanisms for the formation of high density patchy aggregation, we plan to perform more detailed observations and numerical simulations that are able to capture the fine structure of these physical processes in the future.

  19. Characteristics of monsoon inversions over the Arabian Sea observed by satellite sounder and reanalysis data sets

    Directory of Open Access Journals (Sweden)

    S. Dwivedi

    2016-04-01

    Full Text Available Monsoon inversion (MI over the Arabian Sea (AS is one of the important characteristics associated with the monsoon activity over Indian region during summer monsoon season. In the present study, we have used 5 years (2009–2013 of temperature and water vapour measurement data obtained from satellite sounder instrument, an Infrared Atmospheric Sounding Interferometer (IASI onboard MetOp satellite, in addition to ERA-Interim data, to study their characteristics. The lower atmospheric data over the AS have been examined first to identify the areas where MIs are predominant and occur with higher strength. Based on this information, a detailed study has been made to investigate their characteristics separately in the eastern AS (EAS and western AS (WAS to examine their contrasting features. The initiation and dissipation times of MIs, their percentage occurrence, strength, etc., has been examined using the huge database. The relation with monsoon activity (rainfall over Indian region during normal and poor monsoon years is also studied. WAS ΔT values are  ∼  2 K less than those over the EAS, ΔT being the temperature difference between 950 and 850 hPa. A much larger contrast between the WAS and EAS in ΔT is noticed in ERA-Interim data set vis-à-vis those observed by satellites. The possibility of detecting MI from another parameter, refractivity N, obtained directly from another satellite constellation of GPS Radio Occultation (RO (COSMIC, has also been examined. MI detected from IASI and Atmospheric Infrared Sounder (AIRS onboard the NOAA satellite have been compared to see how far the two data sets can be combined to study the MI characteristics. We suggest MI could also be included as one of the semipermanent features of southwest monsoon along with the presently accepted six parameters.

  20. Automatic detection of subglacial lakes in radar sounder data acquired in Antarctica

    Science.gov (United States)

    Ilisei, Ana-Maria; Khodadadzadeh, Mahdi; Dalsasso, Emanuele; Bruzzone, Lorenzo

    2017-10-01

    Subglacial lakes decouple the ice sheet from the underlying bedrock, thus facilitating the sliding of the ice masses towards the borders of the continents, consequently raising the sea level. This motivated increasing attention in the detection of subglacial lakes. So far, about 70% of the total number of subglacial lakes in Antarctica have been detected by analysing radargrams acquired by radar sounder (RS) instruments. Although the amount of radargrams is expected to drastically increase, from both airborne and possible future Earth observation RS missions, currently the main approach to the detection of subglacial lakes in radargrams is by visual interpretation. This approach is subjective and extremely time consuming, thus difficult to apply to a large amount of radargrams. In order to address the limitations of the visual interpretation and to assist glaciologists in better understanding the relationship between the subglacial environment and the climate system, in this paper, we propose a technique for the automatic detection of subglacial lakes. The main contribution of the proposed technique is the extraction of features for discriminating between lake and non-lake basal interfaces. In particular, we propose the extraction of features that locally capture the topography of the basal interface, the shape and the correlation of the basal waveforms. Then, the extracted features are given as input to a supervised binary classifier based on Support Vector Machine to perform the automatic subglacial lake detection. The effectiveness of the proposed method is proven both quantitatively and qualitatively by applying it to a large dataset acquired in East Antarctica by the MultiChannel Coherent Radar Depth Sounder.

  1. Tomographic retrieval approach for mesoscale gravity wave observations by the PREMIER Infrared Limb-Sounder

    Directory of Open Access Journals (Sweden)

    J. Ungermann

    2010-03-01

    Full Text Available PREMIER is one of three candidates for ESA's 7th Earth Explorer mission that are currently undergoing feasibility studies. The main mission objective of PREMIER is to quantify processes controlling atmospheric composition in the mid/upper troposphere and lower stratosphere, a region of particular importance for climate change. To achieve this objective, PREMIER will employ the first satellite Fourier transform infrared limb-imager with a 2-D detector array combined with a millimetre-wave limb-sounder. The infrared limb-imager can be operated in a high spatial resolution mode ("dynamics mode" for observations of small-scale structures in atmospheric temperatures and trace gas fields with unprecedented 3-D sampling (0.5 km in the vertical direction, 50 km along track, 25 km across track. In this paper, a fast tomographic retrieval scheme is presented, which is designed to fully exploit the high-resolution radiance observations of the dynamics mode. Based on a detailed analysis of the "observational filter", we show that the dynamics mode provides unique information on global distributions of gravity waves (GW. The achievable vertical resolution for GW observations has values between the vertical sampling (0.5 km of the dynamics mode and the vertical field of view (about 0.75 km. The horizontal across track resolution corresponds to the horizontal across track sampling of 25 km. Since the achievable along track horizontal resolution is about 70 km, the dynamics mode will provide GW limb-observations with a horizontal resolution comparable to nadir sounders. Compared to previous observations, PREMIER will therefore considerably extend the range of detectable GWs in terms of horizontal and vertical wavelength.

  2. Investigation of the spectral refractive indices of volcanic ash materials using satellite infrared sounder measurements

    Science.gov (United States)

    Ishimoto, H.; Hayashi, Y.

    2016-12-01

    In the IR window region with wavenumber range of 700-1250 cm-1, a volcanic ash cloud shows a typical spectral signature in the Atmospheric Infrared Sounder (AIRS) data and in the Infrared Atmospheric Sounding Interferometer (IASI) data. The spectral signature depends on the Si-O bond characteristics of the erupted silicate material and therefore it is correlated with the mineral type and SiO2 content. In this work, brightness temperature (BT) spectrums of the volcanic ash clouds in the IR window region has been simulated in detail from the radiative transfer calculations by taking into account the appropriate atmospheric profiles, sea surface temperature/emissivity, atmospheric gas absorptions, and ash-scattering properties. From iterative least-square calculations using measured and simulated BTs, we made estimations of the ash refractive index (RI) as well as the ash cloud parameters (optical depth, particles effective radius, and ash cloud pressure heights). Some estimated RIs were consistent with the reported rock types of the volcanoes, which had been previously classified by compositional analyses in the literature. Furthermore, weak absorptions likely due to Si-O and/or Al-O vibrations, which have been proposed in reports from previous laboratory FTIR experiments for some silicate glass samples were identified. These results suggest that the BT features can potentially allow a diagnosis of the rock type from the measurement of ash clouds. The spectral RI estimated from the analyses of data from a satellite infrared sounder can be used to analyze other satellite measurements. In particular, information for the detailed RI in the infrared region contribute to ash cloud quantification and monitoring from measurements by next-generation geostationary satellites, such as the Japanese HIMAWARI-8.

  3. Emitron: microwave diode

    Science.gov (United States)

    Craig, G.D.; Pettibone, J.S.; Drobot, A.T.

    1982-05-06

    The invention comprises a new class of device, driven by electron or other charged particle flow, for producing coherent microwaves by utilizing the interaction of electromagnetic waves with electron flow in diodes not requiring an external magnetic field. Anode and cathode surfaces are electrically charged with respect to one another by electron flow, for example caused by a Marx bank voltage source or by other charged particle flow, for example by a high energy charged particle beam. This produces an electric field which stimulates an emitted electron beam to flow in the anode-cathode region. The emitted electrons are accelerated by the electric field and coherent microwaves are produced by the three dimensional spatial and temporal interaction of the accelerated electrons with geometrically allowed microwave modes which results in the bunching of the electrons and the pumping of at least one dominant microwave mode.

  4. Microwave Oven Observations.

    Science.gov (United States)

    Sumrall, William J.; Richardson, Denise; Yan, Yuan

    1998-01-01

    Explains a series of laboratory activities which employ a microwave oven to help students understand word problems that relate to states of matter, collect data, and calculate and compare electrical costs to heat energy costs. (DDR)

  5. Microwave Service Towers

    Data.gov (United States)

    Department of Homeland Security — This file is an extract of the Universal Licensing System (ULS) licensed by the Wireless Telecommunications Bureau (WTB). It consists of Microwave Transmitters (see...

  6. The Cosmic Microwave Background

    Science.gov (United States)

    Pierpaoli, E.

    2011-03-01

    In these lectures I present the physical aspects of the Cosmic Microwave Background primary and secondary anisotropies; the characteristics of the CMB power spectra and their dependence on cosmological parameters. I also discuss the observational status and future perspectives.

  7. 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

  8. Microwave Processing of Materials

    Science.gov (United States)

    1994-01-01

    reactions in sol-gel processing, gas-phase synthesis , solution evaporation/decomposition, or hydrothermal reactions. Each of these, and other powder... synthesis methods, will be described next. Sol-Gel Decomposition/Drying Microwaves have been used in several of the processing stages to synthesize BaTiO3 ...high surface areas (10-700 m2/g). Hydrothermal Reactions Microwave- hydrothermal processing has been utilized in catalyzing the synthesis of crystalline

  9. 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...... in a microwave oven chamber....... 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...

  10. 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.

  11. Research Progress on Microwave Curing of Epoxy Resin and Its Composites

    Directory of Open Access Journals (Sweden)

    XU Xue-hong

    2016-08-01

    Full Text Available Research progress of microwave curing on epoxy resin and its composites was summarized on the basis of introducing the principle of microwave curing technology and its advantages. The paper focused on the effect of microwave curing on the curing rate of epoxy resin and its composites as well as the mechanical and thermal properties of cured products. Two suitable composite systems for wave curing of powder-strengthened epoxy and fiber-strengthened epoxy and a few key technological problems for industrial application are introduced. The application prospect of microwave curing on epoxy resin and its composites was also presented.

  12. Chemical detoxification of trichloroethylene and 1,1,1-trichloroethane in a microwave discharge plasma reactor at atmospheric pressure

    Energy Technology Data Exchange (ETDEWEB)

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

    1991-12-31

    This report focuses on the application of plasma technology to hazardous waste treatment. Microwave sustained plasmas are used to thermal degrade trichloroethylene and trichloroethane at atmospheric pressure. (JL)

  13. 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.

  14. Assessing Forest Cover Effects on Passive Microwave Snow Retrievals Using 2009 Snow Observations from NASA's Airborne Earth Science Microwave Imaging Radiometer (AESMIR)

    Science.gov (United States)

    Kim, E. J.

    2010-12-01

    Masking of the microwave signature of snow by forest cover remains one of the most significant impediments to global remote sensing of snow, if for no other reason than the large extent of forest areas. The current AMSR-E snow depth/water equivalent retrieval algorithm includes three elements to help address this masking: compensating terms that are functions of forest cover fraction and forest density, and the use of longer-wavelength 10 GHz observations offering less attenuation and scattering (compared to higher frequencies such as 18 GHz) by the canopy. Airborne observations were collected at both 10 and 18 GHz during flights of NASA’s AESMIR sensor. AESMIR is a passive microwave airborne imager covering microwave bands that are essential for observing key Earth System elements such as snow, sea ice, precipitation, soil moisture, ocean winds, sea surface temperature, vegetation, etc. AESMIR includes these bands in an efficient single mechanical package, and can perform conical and cross-track scans to simulate multiple satellite microwave imagers and sounders. As such, it is an Earth Science facility for post-launch calibration and validation of satellite sensors and as well as for pre-launch algorithm development & new microwave remote sensing discovery. It is well-suited as an inter-satellite calibration tool for constellation missions and long-term climate data records. New results from snow-related flights in January, 2009 will be presented. Imagery at 10 and 18 GHz will be presented from the flights over forested sites in the northeastern US, along with snow ground truth comparisons. The performance of the AMSR-E forest correction will be explored using these frequencies.

  15. Dielectric heating. Technologies; Chauffage dielectrique. Technologies

    Energy Technology Data Exchange (ETDEWEB)

    Roussy, G. [Universite Henri-Poincare, Dir. de Recherche, 54 - Nancy (France); Rochas, J.F. [Societe Sairem, 69 - Lyon (France); Oberlin, C. [Electricite de France (EDF), 75 - Paris (France)

    2003-08-01

    The electrothermal heating processes are of two types: the indirect heating (indirect resistance, infrared, indirect arc and plasma heating) in which the energy transfer from the source to the receptor complies with the usual thermal laws, and the direct heating (direct ohmic, induction, high-frequency, microwave, electron bombardment, laser and direct arc heating) in which the receptor is crossed by an electric current which generates a heat release inside the receptor. This paper treats of the technologies used in high frequency and microwave heating: 1 - techniques of implementation of high-frequency (HF) heating: HF generator, energy transmission line, HF applicator, impedance adjustment system, auxiliary devices; 2 - techniques of implementation of microwave heating: microwave generator, wave guide, microwave applicator, impedance adjustment circuit, auxiliary devices. (J.S.)

  16. NOAA Climate Data Record (CDR) of Intersatellite Calibrated Clear-Sky High Resolution Infrared Radiation Sounder (HIRS) Channel 12 Brightness Temperature Version 3

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The High-Resolution Infrared Radiation Sounder (HIRS) of intersatellite calibrated channel 12 brightness temperature (TB) product is a gridded global monthly time...

  17. Sounder PEATE SNPP CrIMSS IR MW Retrieval Level 3 Daily Observations 1 degree x 1 degree V10 (SPL3NP2D) at GES DISC

    Data.gov (United States)

    National Aeronautics and Space Administration — The Sounder PEATE Level 3 Product provides global cylindrical grids summarizing Level-2 data from a given instrument suite for one day, 8-consecutive days, or one...

  18. Sounder PEATE SNPP CrIMSS IR MW Retrieval Level 3 Monthly Observations 1 degree x 1 degree V10 (SPL3NP2M) at GES DISC

    Data.gov (United States)

    National Aeronautics and Space Administration — The Sounder PEATE Level 3 Product provides global cylindrical grids summarizing Level-2 data from a given instrument suite for one day, 8-consecutive days, or one...

  19. Sound velocity from inverted echo sounders (IES) in the western Pacific Ocean from 1992-08-26 to 1993-03-22 (NODC Accession 9300159)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This accession contains inverted echo sounder data collected from two stations in the western Pacific, TPW nominally @ 2S and 154E and TPE nominally @ 2S and 164E....

  20. 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...

  1. 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.

  2. Satellite Sounder Observations of Contrasting Tropospheric Moisture Transport Regimes: Saharan Air Layers, Hadley Cells, and Atmospheric Rivers

    Energy Technology Data Exchange (ETDEWEB)

    Nalli, Nicholas R.; Barnet, Christopher D.; Reale, Tony; Liu, Quanhua; Morris, Vernon R.; Spackman, J. Ryan; Joseph, Everette; Tan, Changyi; Sun, Bomin; Tilley, Frank; Leung, L. Ruby; Wolfe, Daniel

    2016-12-01

    This paper examines the performance of satellite sounder atmospheric vertical moisture proles (AVMP) under tropospheric conditions encompassing moisture contrasts driven by convection and advection transport mechanisms, specifically Atlantic Ocean Saharan air layers (SALs) and Pacific Ocean moisture conveyer belts (MCBs) commonly referred to as atmospheric rivers (ARs), both of these being mesoscale to synoptic meteorological phenomena within the vicinity of subtropical Hadley subsidence zones. Operational AVMP environmental data records retrieved from the Suomi National Polar-orbiting Partnership (SNPP) NOAA-Unique Combined Atmospheric Processing System (NUCAPS) are collocated with dedicated radiosonde observations (RAOBs) obtained from ocean-based intensive field campaigns; these RAOBs provide uniquely independent correlative truth data not assimilated into numerical weather prediction models for satellite sounder validation over open ocean. Using these marine-based data, we empirically assess the performance of the operational NUCAPS AVMP product for detecting and resolving these tropospheric moisture features over otherwise RAOB-sparse regions.

  3. The GEISA system in 1996: towards an operational tool for the second generation vertical sounders radiance simulation.

    Science.gov (United States)

    Jacquinet-Husson, N.; Scott, N. A.; Chedin, A.; Bonnet, B.; Barbe, A.; Tyuterev, V. G.; Champion, J. P.; Winnewisser, M.; Brown, L. R.; Gamache, R.; Golovko, V. F.; Chursin, A. A.

    1998-05-01

    Since their creation, in 1974, the GEISA (Gestion et Etude des Informations Spectroscopiques Atmospheriques: Management and Study of Atmospheric Spectroscopic Information) database system (more than 730,000 entries between 0 and 22,656 cm-1, corresponding to 40 molecules and 86 isotopic species, in its 1992 edition) and the associated software have been widely used for forward atmospheric radiative transfer modelling, with the maximum reliability, tractability and efficiency. For the upcoming high spectral resolution sounders like IASI (Infrared Atmospheric Sounding Interferometer) and AIRS (Atmospheric InfraRed Sounder), more complete and accurate laboratory measurements of spectroscopic parameters, presently included in the databases, are required, and more sophisticated theoretical radiative transfer modelling should be developed. Consequently, it is intended to elaborate the GEISA database as an interactive tool, named GEISA/IASI, designed for providing spectroscopic information tailored to the IASI sounding radiative transfer modelling.

  4. Vortices at Microwave Frequencies

    Science.gov (United States)

    Silva, Enrico; Pompeo, Nicola; Dobrovolskiy, Oleksandr V.

    2017-11-01

    The behavior of vortices at microwave frequencies is an extremely useful source of information on the microscopic parameters that enter the description of the vortex dynamics. This feature has acquired particular relevance since the discovery of unusual superconductors, such as cuprates. Microwave investigation then extended its field of application to many families of superconductors, including the artificially nanostructured materials. It is then important to understand the basics of the physics of vortices moving at high frequency, as well as to understand what information the experiments can yield (and what they can not). The aim of this brief review is to introduce the readers to some basic aspects of the physics of vortices under a microwave electromagnetic field, and to guide them to an understanding of the experiment, also by means of the illustration of some relevant results.

  5. Physics of the Microwave Oven

    Science.gov (United States)

    Vollmer, Michael

    2004-01-01

    This is the first of two articles about the physics of microwave ovens. This article deals with the generation of microwaves in the oven and includes the operation of the magnetrons, waveguides and standing waves in resonant cavities. It then considers the absorption of microwaves by foods, discussing the dielectric relaxation of water,…

  6. Industrial scale microwave processing of tomato juice using a novel continuous microwave system.

    Science.gov (United States)

    Stratakos, Alexandros Ch; Delgado-Pando, Gonzalo; Linton, Mark; Patterson, Margaret F; Koidis, Anastasios

    2016-01-01

    This study evaluated the effect of an industrial scale continuous flow microwave volumetric heating system in comparison to conventional commercial scale pasteurisation for the processing of tomato juice in terms of physicochemical properties, microbial characteristics and antioxidant capacity. The effect against oxidative stress in Caco-2 cells, after in vitro digestion was also investigated. Physicochemical and colour characteristics of juices were very similar between technologies and during storage. Both conventional and microwave pasteurisation inactivated microorganisms and kept them in low levels throughout storage. ABTS[Symbol: see text](+) values, but not ORAC, were higher for the microwave pasteurised juice at day 0 however no significant differences between juices were observed during storage. Juice processed with the microwave system showed an increased cytoprotective effect against H2O2 induced oxidation in Caco-2 cells. Organoleptic analysis revealed that the two tomato juices were very similar. The continuous microwave volumetric heating system appears to be a viable alternative to conventional pasteurisation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Cryogenic MEMS Technology for Sensing Applications Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The development of cryogenic microwave components, such as focal plane polarization modulators, first requires an RF MEMS switching technology that operates...

  8. Ultraviolet Light Source Using Electrodeless Microwave Discharge

    Science.gov (United States)

    Nishikawa, Taku; Toyoda, Hirotaka

    2015-09-01

    Surface treatment technologies using ultraviolet (UV) light, such as organic residue removal, surface modification or sterilization, are widely used. So far, UV lamps using DC discharge with electrodes inside the lamp tube is commonly used. However, sputtering of electrode materials sometimes causes deposition on the inner tube surface as well as degradation of the electrodes, resulting in short life time of the lamp tube. In this study, we propose an electrodeless UV mercury (Hg) lamp source using microwave power. 2.45 GHz Microwave power (<4 kW) from a power supply is divided into four power lines using branch waveguides. A mercury lamp tube (diameter: 9.6 mm, length: 42 cm, Hg: 13.5 mg, Ar: 1 Torr) is inserted into the branch waveguides and microwave power is coupled to the plasma. Emission from the lamp is monitored by a monochromator and an 254 nm UV monitor. Lamp temperature is also measured by a thermography camera and tube temperature up to 900 K with good uniformity along ~ 30 cm was observed. Uniformity of the 254 nm UV light intensity was +15 % along the lamp tube. The maximum UV light intensity of 64 mW/cm2 was observed at a microwave power of 4 kW.

  9. Fundamentals of microwave photonics

    CERN Document Server

    Urick, V J; McKinney , Jason D

    2015-01-01

    A comprehensive resource to designing andconstructing analog photonic links capable of high RFperformanceFundamentals of Microwave Photonics provides acomprehensive description of analog optical links from basicprinciples to applications.  The book is organized into fourparts. The first begins with a historical perspective of microwavephotonics, listing the advantages of fiber optic links anddelineating analog vs. digital links. The second section coversbasic principles associated with microwave photonics in both the RFand optical domains.  The third focuses on analog modulationformats-starti

  10. 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.

  11. Microwave induced fast pyrolysis of scrap rubber tires

    Science.gov (United States)

    Ani, Farid Nasir; Mat Nor, Nor Syarizan

    2012-06-01

    Pyrolysis is the thermal degradation of carbonaceous solid by heat in the absence of oxygen. The feedstocks, such as biomass or solid wastes are heated to a temperature between 400 and 600°C, without introducing oxygen to support the reaction. The reaction produces three products: gas, pyro-fuel oil and char. This paper presents the techniques of producing pyro-oil from waste tires, as well as investigation of the fuel properties suitable for diesel engine applications. In this study, microwave heating technique is employed to pyrolyse the used rubber tires into pyro-oil. Thermal treatment of as received used rubber tires is carried out in a modified domestic microwave heated fixed bed technology. It has been found that, rubber tires, previously used by various researchers, are poor microwave absorbers. Studies have shown that an appropriate microwave-absorbing material, such as biomass char or activated carbon, could be added to enhance the pyrolysis process; thus producing the pyro-oil. The characteristics of pyro-oil, as well as the effect of microwave absorber on its yield, are briefly described in this paper. The temperature profiles during the microwave heating process are also illustratively emphasized. The study provides a means of converting scrap tires into pyro-oil and pyrolytic carbon black production. The proposed microwave thermal conversion process therefore has the potentials of substantially saving time and energy.

  12. Digital channel sounder for remote sensing of scatterers in mobile radio environment

    Science.gov (United States)

    Lorenz, Rudolf Werner; Kadel, Gerhard

    1992-02-01

    A channel sounder called RUSK 400 is described. It is capable of recording complex impulse responses (IRs) in mobile environment. Thanks to digital signal processing, RUSK 400 measures IRs with large dynamic range. RUSK 400 was calibrated to allow for quantitative analysis. Doppler analysis of the measured results can be performed because the data are stored rapidly, and therefore, the sampling theorem can be fulfilled. For determination of delays, the resolution is restricted to about 5 microns because of the small bandwidth of only 400 kHz. The resolution is good enough to perform propagation measurements with the goal of improving of propagation models which use topographical terrain data bases. The determination of angles of arrival is restricted; reasons are given and discussed. The shortcomings of poor resolution and left-right ambiguity can be overcome if it is possible to measure complex IRs at the same location by driving in different directions. RUSK 400 will be used for quantitative determination of magnitudes of waves scattered by terrain slopes. The results will be used to improve automatic field strength prediction methods and estimation of the delay spread caused by mountains.

  13. Some results of analysis of inverted echo-sounder records from the Atlantic Equatorial region

    Directory of Open Access Journals (Sweden)

    Alberto dos Santos Franco

    1985-01-01

    Full Text Available The tidal analysis of data from the Equatorial region, given by inverted echo-sounders, show considerable residuals in the frequency band of approximately 2 cycles per day. In the even harmonics of 4 and 6 cycles per day, tidal components statistically not negligible are also identified. Spectral analysis of temperature series from the same area show, on the other hand, variabilities in the same frequency bands, which suggests the occurrence of internal waves with energy distributed in these frequency bands, in the Atlantic Equatorial area.Análises de dados de maré, da zona equatorial, obtidos com ecobatímetros invertidos, mostram consideráveis resíduos na faixa de freqüências com aproximadamente dois ciclos por dia. Nos harmônicos pares com 4 e 6 ciclos por dia são também identificadas componentes de maré estatisticamente não desprezíveis. Análises espectrais de séries de temperatura obtidas na mesma área mostram, 218 por outro lado, variabilidades na mesma faixa de freqüências, o que sugere a ocorrência, na área equatorial Atlântica, de ondas internas com energia distribuída nessas faixas espectrais.

  14. Radiometric comparison of Mars Climate Sounder and Thermal Emission spectrometer measurements

    Science.gov (United States)

    Bandfield, Joshua L.; Wolff, Michael J.; Smith, Michael D.; Schofield, John T.; McCleese, Daniel J.

    2013-07-01

    Mars Climate Sounder (MCS) nadir oriented thermal infrared and solar channel measurements are compared with Thermal Emission Spectrometer (TES) measurements across multiple Mars years. Thermal infrared measurements were compared by convolving the TES data using the MCS spectral band passes. The MCS solar channel measurements were calibrated using Compact Reconnaissance Imaging Spectrometer for Mars observations to provide the proper gain factor (3.09 × 10-3 W sr-1 m-2 μm-1). The comparisons of the datasets show that day and night surface and atmospheric temperatures are within 3 K over the course of 5 martian years, after accounting for the local time differences. Any potential interannual variations in global average temperature are masked by calibration and modeling uncertainties. Previous work attributed apparent interannual global surface and atmospheric temperature variations to major dust storm activity; however, this variation has since been attributed to a calibration error in the TES dataset that has been corrected. MCS derived Lambert albedos are slightly higher than TES measurements acquired over the same season and locations. Most of this difference can be attributed to the spectral response functions of MCS and TES. Consistent with previous work, global albedo is highly variable (˜6%) and this variability must be taken into account when determining long term global trends. Vertical aerosol distributions were also derived from the calibrated MCS visible channel limb measurements, demonstrating the utility of the MCS visible channel data for monitoring of aerosols.

  15. User expectations for multibeam echo sounders backscatter strength data-looking back into the future

    Science.gov (United States)

    Lucieer, Vanessa; Roche, Marc; Degrendele, Koen; Malik, Mashkoor; Dolan, Margaret; Lamarche, Geoffroy

    2017-05-01

    With the ability of multibeam echo sounders (MBES) to measure backscatter strength (BS) as a function of true angle of insonification across the seafloor, came a new recognition of the potential of backscatter measurements to remotely characterize the properties of the seafloor. Advances in transducer design, digital electronics, signal processing capabilities, navigation, and graphic display devices, have improved the resolution and particularly the dynamic range available to sonar and processing software manufacturers. Alongside these improvements the expectations of what the data can deliver has also grown. In this paper, we identify these user-expectations and explore how MBES backscatter is utilized by different communities involved in marine seabed research at present, and the aspirations that these communities have for the data in the future. The results presented here are based on a user survey conducted by the GeoHab (Marine Geological and Biological Habitat Mapping) association. This paper summarises the different processing procedures employed to extract useful information from MBES backscatter data and the various intentions for which the user community collect the data. We show how a range of backscatter output products are generated from the different processing procedures, and how these results are taken up by different scientific disciplines, and also identify common constraints in handling MBES BS data. Finally, we outline our expectations for the future of this unique and important data source for seafloor mapping and characterisation.

  16. Monitoring of atmospheric composition using the thermal infrared IASI/MetOp sounder

    Directory of Open Access Journals (Sweden)

    C. Clerbaux

    2009-08-01

    Full Text Available Atmospheric remote sounding from satellites is an essential component of the observational strategy deployed to monitor atmospheric pollution and changing composition. The IASI nadir looking thermal infrared sounder onboard MetOp will provide 15 years of global scale observations for a series of key atmospheric species, with unprecedented spatial sampling and coverage. This paper gives an overview of the instrument's capability for measuring atmospheric composition in the perspective of chemistry and air quality. The assessment is made in terms of species, accuracy and vertical information. Global distributions are presented for CO, CH4, O3 (total and tropospheric, HNO3, NH3, and volcanic SO2. Local distributions of organic species measured during fire events, such as C2H4, CH3OH, HCOOH, and PAN are also shown. For each species or process, the link is made to specialized papers in this issue.

  17. Microwave extraction of bioactive compounds

    Directory of Open Access Journals (Sweden)

    Monika Blekić

    2011-01-01

    Full Text Available Microwave extraction presents novel extraction and treatment method for food processing. In paper, several examples of microwave extraction of bioactive compounds are presented. Also, novel innovative equipment for microwave extraction and hydrodiffusion with gravitation is presented. Advantage of using novel equipment for microwave extraction is shown, and it include, shorter treatment time, less usage or without any solvent use. Novel method is compared to standard extraction methods. Some positive and negative aspects of microwave heating can be observed, and also its influence on development of oxidation in sunflower oil subjected to microwave heating. Also, use of microwaves for the extraction of essential oils is shown. One can also see the advantages of solvent-free microwave extraction of essential oil from aromatic herbs in comparison with the standard extraction, and determination of antioxidant components in rice bran oil extracted by microwave-assisted method. Comparison of microwave and ultrasound extraction, as well as positive and negative aspects of the combination of microwaves and ultrasound is described.

  18. 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…

  19. 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 f...

  20. Nonlinear Microwave Optomechanics

    NARCIS (Netherlands)

    Shevchuk, O.

    2017-01-01

    The nonlinearity is essential for creation of non-classical states of the cavity or mechanical resonator such as squeezed or cat states. A microwave cavity can be made nonlinear by, for instance, adding Josephson junctions. The mechanical resonator is inherently nonlinear. The radiation pressure

  1. Smelting Magnesium Metal using a Microwave Pidgeon Method

    Science.gov (United States)

    Wada, Yuji; Fujii, Satoshi; Suzuki, Eiichi; Maitani, Masato M.; Tsubaki, Shuntaro; Chonan, Satoshi; Fukui, Miho; Inazu, Naomi

    2017-04-01

    Magnesium (Mg) is a lightweight metal with applications in transportation and sustainable battery technologies, but its current production through ore reduction using the conventional Pidgeon process emits large amounts of CO2 and particulate matter (PM2.5). In this work, a novel Pidgeon process driven by microwaves has been developed to produce Mg metal with less energy consumption and no direct CO2 emission. An antenna structure consisting of dolomite as the Mg source and a ferrosilicon antenna as the reducing material was used to confine microwave energy emitted from a magnetron installed in a microwave oven to produce a practical amount of pure Mg metal. This microwave Pidgeon process with an antenna configuration made it possible to produce Mg with an energy consumption of 58.6 GJ/t, corresponding to a 68.6% reduction when compared to the conventional method.

  2. Abnormal Winter Melting of the Arctic Sea Ice Cap Observed by the Spaceborne Passive Microwave Sensors

    Directory of Open Access Journals (Sweden)

    Seongsuk Lee

    2016-12-01

    Full Text Available The spatial size and variation of Arctic sea ice play an important role in Earth’s climate system. These are affected by conditions in the polar atmosphere and Arctic sea temperatures. The Arctic sea ice concentration is calculated from brightness temperature data derived from the Defense Meteorological Satellite program (DMSP F13 Special Sensor Microwave/Imagers (SSMI and the DMSP F17 Special Sensor Microwave Imager/Sounder (SSMIS sensors. Many previous studies point to significant reductions in sea ice and their causes. We investigated the variability of Arctic sea ice using the daily and monthly sea ice concentration data from passive microwave observations to identify the sea ice melting regions near the Arctic polar ice cap. We discovered the abnormal melting of the Arctic sea ice near the North Pole even during the summer and the winter. This phenomenon is hard to explain only surface air temperature or solar heating as suggested by recent studies. We propose a hypothesis explaining this phenomenon. The heat from the deep sea in Arctic Ocean ridges and/or the hydrothermal vents might be contributing to the melting of Arctic sea ice. This hypothesis could be verified by the observation of warm water column structure below the melting or thinning arctic sea ice through the project such as Coriolis dataset for reanalysis (CORA.

  3. WWLLN lightning and satellite microwave radiometrics at 37 to 183 GHz: Thunderstorms in the broad tropics

    Science.gov (United States)

    Solorzano, N. N.; Thomas, J. N.; Hutchins, M. L.; Holzworth, R. H.

    2016-10-01

    We investigate lightning strokes and deep convection through the examination of cloud-to-ground (CG) lightning from the World Wide Lightning Location Network (WWLLN) and passive microwave radiometer data. Microwave channels at 37 to 183.3 GHz are provided by the Tropical Rainfall Measuring Mission satellite (TRMM) Microwave Imager (TMI) and the Special Sensor Microwave Imager/Sounder (SSMIS) on the Defense Meteorological Satellite Program (DMSP) satellite F16. The present study compares WWLLN stroke rates and minimum radiometer brightness temperatures (Tbs) for two Northern Hemisphere and Southern Hemisphere summers (2009-2011) in the broad tropics (35°S to 35°N). To identify deep convection, we use lightning data and Tbs derived from all channels and differences in the Tbs (ΔTbs) of the three water vapor channels near 183.3 GHz. We find that stroke probabilities increase with increasing Tb depressions for all frequencies examined. Moreover, we apply methods that use the 183.3 GHz channels to pinpoint deep convection associated with lightning. High lightning stroke probabilities are found over land regions for both intense and relatively weak convective systems, although the TMI 85 GHz results should be used with caution as they are affected by a 7 km gap between the conical scans. Over the ocean, lightning is associated mostly with larger Tb depressions. Generally, our results support the noninductive thundercloud charging mechanism but do not rule out the inductive mechanism during the mature stages of storms. Lastly, we present a case study in which lightning stroke rates are used to reconstruct microwave radiometer Tbs.

  4. 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

  5. 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.

  6. Microwave milk pasteurization without food safety risk

    Directory of Open Access Journals (Sweden)

    Gábor Géczi

    2013-02-01

    Full Text Available 96 Normal 0 false false false CS JA X-NONE According to nutrition science, milk and milk products are essential food for humans. The primary processing of milk includes its storage, separation, homogenization and the pasteurization process as well. The latter is a kind of heat treatment, which has been used to extend the storage life of food since the late 18th century. Although heat treatment of milk can be achieved through the use of microwave technology, the inhomogeneity of electromagnetic fields leads to an uneven distribution of temperature in the food products, therefore precluding their use in industry. The pasteurization operation is very often Critical Controll Point (CCP according of food safety systems. In recent years our research team has developed continuously operating heat treatment pilot-plant equipment, capable of measuring and contrasting the effects of different heat treatment methods, such as thermostat-controlled water baths and microwave energy, on liquid food products. We examined and compared protein, fat and bacterial content in samples of fresh cow milk with heat-treated cow milk samples. In addition, storage experiments were carried out under a microscope and recordings made of fat globules. Our results so far show that the microwave heat treatment is equivalent to the convection manner pasteurization technology, as we found no difference between the heat-treated products.doi:10.5219/260

  7. Intracity Quantum Communication via Thermal Microwave Networks

    Directory of Open Access Journals (Sweden)

    Ze-Liang Xiang

    2017-03-01

    Full Text Available Communication over proven-secure quantum channels is potentially one of the most wide-ranging applications of currently developed quantum technologies. It is generally envisioned that in future quantum networks, separated nodes containing stationary solid-state or atomic qubits are connected via the exchange of optical photons over large distances. In this work, we explore an intriguing alternative for quantum communication via all-microwave networks. To make this possible, we describe a general protocol for sending quantum states through thermal channels, even when the number of thermal photons in the channel is much larger than 1. The protocol can be implemented with state-of-the-art superconducting circuits and enables the transfer of quantum states over distances of about 100 m via microwave transmission lines cooled to only T=4  K. This opens up new possibilities for quantum communication within and across buildings and, consequently, for the implementation of intracity quantum networks based on microwave technology only.

  8. Post biopsy Liver Hemorrhage Successfully Controlled by Ultrasound-guided Percutaneous Microwave Ablation

    Directory of Open Access Journals (Sweden)

    Ophelia Ka Heng Wai

    2016-01-01

    Full Text Available Percutaneous microwave coagulation therapy has been one of the major new developments in tumor ablation. Microwave ablation has also been used intraoperatively to achieve hemostasis at surgical margins in laparotomy. However, the use of microwave ablation for coagulation and hemostasis through percutaneous approach has not been described in the literature. Here, we report a case of hepatic amyloidosis with massive post biopsy liver hemorrhage, which could not be by transarterial embolization, and subsequently controlled by ultrasound-guided percutaneous microwave ablation. To the best of our knowledge, this is the first reported case of this technology application in human.

  9. [Orthogonal experiment of the extraction of triterpenoids from stems of Hyptis suaveolens with microwave].

    Science.gov (United States)

    Huang, Xiu-xiang; Lin, Cui-wu; Chen, Li-fen; Yuan, Xia; Ning, Zi-hua

    2008-01-01

    To study the best technology of the extraction of triterpenoids from the stems of Hyptis suaveolens with microwave. Orthogonal experiment was carried out to investigate 4 influential factors as follows: the time (A), the temperature (B), the solid fluid compared to (C), the NaOH density (D). The optimal conditions for microwave extraction were A1 B2 C3 D2. The microwave extraction can extract more triterpenoids from the stems of Hyptis suaveolens in shorter time with less energy. It also shows a promising prospect for leaching the effective constituents from Chinese herbal medicine by using microwave extraction.

  10. Phase Change Material for Temperature Control of Imager or Sounder on GOES Type Satellites in GEO

    Science.gov (United States)

    Choi, Michael

    2013-01-01

    An imager or sounder on satellites, such as the Geostationary Operational Environmental Satellite (GOES), in geostationary orbit (GEO) has a scan mirror and motor in the scan cavity. The GEO orbit is 24 hours long. During part of the orbit, direct sunlight enters the scan aperture and adds heat to components in the scan cavity. Solar heating also increases the scan motor temperature. Overheating of the scan motor could reduce its reliability. For GOES-N to P, a radiator with a thermal louver rejects the solar heat absorbed to keep the scan cavity cool. A sunshield shields the radiator/louver from the Sun. This innovation uses phase change material (PCM) in the scan cavity to maintain the temperature stability of the scan mirror and motor. When sunlight enters the scan aperture, solar heating causes the PCM to melt. When sunlight stops entering the scan aperture, the PCM releases the thermal energy stored to keep the components in the scan cavity warm. It reduces the heater power required to make up the heat lost by radiation to space through the aperture. This is a major advantage when compared to a radiator/ louver. PCM is compact because it has a high solid-to-liquid enthalpy. Also, it could be spread out in the scan cavity. This is another advantage. Paraffin wax is a good PCM candidate, with high solid-to-liquid enthalpy, which is about 225 kJ/kg. For GOES-N to P, a radiator with a louver rejects the solar heat that enters the aperture to keep the scan cavity cool. For the remainder of the orbit, sunlight does not enter the scan aperture. However, the radiator/louver continues radiating heat to space because the louver effective emittance is about 0.12, even if the louver is fully closed. This requires makeup heater power to maintain the temperature within the stability range.

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

    Science.gov (United States)

    Myrabo, Leik N.

    2008-04-01

    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.

  12. Microwave synthesis and actuation of shape memory polycaprolactone foams with high speed

    Science.gov (United States)

    Zhang, Fenghua; Zhou, Tianyang; Liu, Yanju; Leng, Jinsong

    2015-06-01

    Microwave technology is a highly effective approach to fast and uniform heating. This article investigates that the microwave heating as a novel method is used to rapidly foam and actuate biocompatible and biodegradable shape memory crosslinked-polycaprolactone (c-PCL) foams. The optical microscope proves that the resulting c-PCL foams have homogenous pore structure. Mechanical behavior and shape memory performance of c-PCL foams are investigated by static materials testing. Shape recovery ratio is approximately 100% and the whole recovery process takes only 98 s when trigged by microwave. Due to the unique principle of microwave heating, the recovery speed of c-PCL foams in microwave oven is several times faster than that in hot water and electric oven. Hence compared to the traditional heating methods, microwave is expected to bring more advantages to modern industry and scientific research in the field of smart materials and structures.

  13. Microwave generation with an inner-modulated laser and parallel Mach-Zehnder interferometers

    Science.gov (United States)

    Fan, Zhaojin; Zeng, Xiaodong; Cao, Changqing; Feng, Zhejun; Lai, Zhi; Cheng, Yinghong; Chen, Xuanqi; Wang, Xiang; Pan, Zewei; Luo, Long; Liu, Yutao

    2017-11-01

    Using an inner-frequency-modulated semiconductor laser, two parallel Mach-Zehnder delay-line interferometers and feedback control loop technique, we generate microwaves. The frequency of the Littrow-structure semiconductor laser is modified by a lead zirconate titanate actuator that covers a wideband modulating range. One long delay-line interferometer generates microwaves; the second short delay-line interferometer controls the linearity of the modulate laser and assures microwave stability by a feedback loop. Thus, this method, in theory, should produce more than one hundred GHz microwave. We experimentally generated 1.743 GHz to 5.134 GHz microwaves. This technology opens a new path for developments in microwave photonics.

  14. 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

  15. Models Support Energy-Saving Microwave Technologies

    Science.gov (United States)

    2012-01-01

    During the Apollo Program, astronauts on the Moon encountered a small menace that created big problems: lunar dust. Similar to how tiny bits of Styrofoam behave on Earth adhering to anything they touch lunar dust sticks to spacesuits, spacecraft, tools, and equipment, and is extremely difficult to remove. The clingy nature of the substance is partly due to its electrostatic charge but is also due to its physical characteristics: The sharp, irregularly shaped grains have edges like burrs and feel like abrasive talcum powder to the touch. Not only a nuisance, Moon dust is also a potential health and safety risk. Because it is often laden with ultraviolet radiation and high iron content, it can be detrimental if it gets into the eyes or lungs. In fact, some of the particles are so small that the human body does not even detect them in order to expel them. On the Apollo missions, equipment covered with the dark-colored Moon dust suffered from the absorption of sunlight and tended to overheat. NASA has investigated tools and techniques to manage the sticky stuff, including magnets, vacuums, and shields. In 2009, Kennedy Space Center collaborated with a small business to investigate a method to harden the Moon's surface in a sense, to pave the surface so astronauts and robots could land, drive, and work without disrupting and scattering the material.

  16. Cosmic Microwave Background Anisotropies

    OpenAIRE

    Hu, Wayne; Dodelson,Scott

    2001-01-01

    Cosmic microwave background (CMB) temperature anisotropies have and will continue to revolutionize our understanding of cosmology. The recent discovery of the previously predicted acoustic peaks in the power spectrum has established a working cosmological model: a critical density universe consisting of mainly dark matter and dark energy, which formed its structure through gravitational instability from quantum fluctuations during an inflationary epoch. Future observations should test this mo...

  17. Microwave susceptibility experiments

    Energy Technology Data Exchange (ETDEWEB)

    McConaghy, C.

    1984-05-29

    In certain experimental environments, systems can be affected or damaged by microwave pulses. I have conducted tests at LLNL to understand the phenomenology of microwave susceptibility of system components and subsystem components. To date, my experiments have concentrated on bipolar transistors, similar to what might be used in discrete analog circuits, and on CMOS RAM chips, which might be used in a computer memory system. I observed a decrease in failure energies for both the transistor and the integrated curcuit as I shortened the microwave pulse width. An S band (2.86 GHz) transmit/receive (T/R) tube has also been tested both at S band and at X band (8.16 GHz). The S band pulse had limitations in rise-time from zero power, which had an effect on the amount of power that could be transmitted through the T/R tube, as much as 0.7% of the incident power passed through the tube. All tests were conducted in closed-waveguide or coax test-fixtures, in contrast to the anechoic chambers utilized by other experimenters. I have used both S band and X band Klystron generators. For very high power (greater than 1 MW), I used an additional pulse-compression cavity at S band. Other subsystem components such as an X band mixer and an X band T/R tube will be tested in the future. 8 references.

  18. 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.

  19. Further Developments in Microwave Ablation of Prostate Cells

    Science.gov (United States)

    Arndt, G. Dickey; Ngo, Phong

    2005-01-01

    A report presents additional information about the subject matter of Microwave Treatment of Prostate Cancer and Hyperplasia (MSC-23049), NASA Tech Briefs, Vol. 29, No. 6 (June 2005), page 62. To recapitulate: the basic idea is to use microwaves to heat and thereby kill small volumes of unhealthy prostate tissue. The prostate is irradiated with microwaves from one or more antennas positioned near the prostate by means of catheters inserted in the urethra and/or colon. The microwave frequency, power, and exposure time, phasing, positions, and orientations of the antennas may be chosen to obtain the desired temperature rise in the heated region and to ensure that the location and extent of the heated region coincides with the region to be treated to within a few millimeters. Going beyond the description in the cited previous article, the report includes a diagram that illustrates typical placement of urethra and colon antenna catheters and presents results of computationally simulated prostate-heating profiles for several different combinations of antenna arrangements, frequencies, and delivered- energy levels as well as experimental results within phantom materials. The advantage of the two-antenna technology is that the heat generated at each antenna is significantly reduced from that associated with only one antenna. The microwave energy radiated from each antenna is focused at the tumor center by adjusting the phasing of the irradiated microwave signal from the antennas.

  20. 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.

  1. Analysis and evaluation of WRF microphysical schemes for deep moist convection over south-eastern South America (SESA using microwave satellite observations and radiative transfer simulations

    Directory of Open Access Journals (Sweden)

    V. S. Galligani

    2017-10-01

    coincident microwave observations up to 190 GHz (with observations from Tropical Rainfall Measuring Mission's (TRMM Microwave Imager (TMI, Microwave Humidity Sounder (MHS and Special Sensor Microwave Imager/Sounder (SSMI/S using the χ2 test. Good agreement is obtained with all observations provided special care is taken to represent the scattering properties of the snow and graupel species.

  2. Analysis and evaluation of WRF microphysical schemes for deep moist convection over south-eastern South America (SESA) using microwave satellite observations and radiative transfer simulations

    Science.gov (United States)

    Sol Galligani, Victoria; Wang, Die; Alvarez Imaz, Milagros; Salio, Paola; Prigent, Catherine

    2017-10-01

    microwave observations up to 190 GHz (with observations from Tropical Rainfall Measuring Mission's (TRMM) Microwave Imager (TMI), Microwave Humidity Sounder (MHS) and Special Sensor Microwave Imager/Sounder (SSMI/S)) using the χ2 test. Good agreement is obtained with all observations provided special care is taken to represent the scattering properties of the snow and graupel species.

  3. An introduction to microwave measurements

    CERN Document Server

    Basu, Ananjan

    2014-01-01

    IntroductionAim and ScopeGeneral Electronic Measurements and Frequency LimitationsApplications and Importance of Microwave MeasurementsOverview of State-of-the-Art Microwave MeasurementsReferencesBackground InformationS-Parameters and Related Black-Box RepresentationSpectra of Commonly Encountered SignalsMicrowave Filters and Directional CouplersMicrowave Mixers, Switches, Attenuators, and ConnectorsConclusionProblemsReferencesTraditional Measurement TechniquesThe Power MeterTransmission MeasurementReflection MeasurementConclusionProblemsReferencesVector Network AnalyzerEnhancement of Scalar M

  4. The Microwave SQUID Multiplexer

    Science.gov (United States)

    Mates, John Arthur Benson

    2011-12-01

    This thesis describes a multiplexer of Superconducting Quantum Interference Devices (SQUIDs) with low-noise, ultra-low power dissipation, and great scalability. The multiplexer circuit measures the magnetic flux in a large number of unshunted rf SQUIDs by coupling each SQUID to a superconducting microwave resonator tuned to a unique resonance frequency and driving the resonators from a common feedline. A superposition of microwave tones measures each SQUID simultaneously using only two coaxial cables between the cryogenic device and room temperature. This multiplexer will enable the instrumentation of arrays with hundreds of thousands of low-temperature detectors for new applications in cosmology, materials analysis, and nuclear non-proliferation. The driving application of the Microwave SQUID Multiplexer is the readout of large arrays of superconducting transition-edge sensors, by some figures of merit the most sensitive detectors of electromagnetic signals over a span of more than nine orders of magnitude in energy, from 40 GHz microwaves to 200 keV gamma rays. Modern transition-edge sensors have noise-equivalent power as low as 10-20 W / Hz1/2 and energy resolution as good as 2 eV at 6 keV. These per-pixel sensitivities approach theoretical limits set by the underlying signals, motivating a rapid increase in pixel count to access new science. Compelling applications, like the non-destructive assay of nuclear material for treaty verification or the search for primordial gravity waves from inflation use arrays of these detectors to increase collection area or tile a focal plane. We developed three generations of SQUID multiplexers, optimizing the first for flux noise 0.17 muPhi0 / Hz1/2, the second for input current noise 19 pA / Hz1/2, and the last for practical multiplexing of large arrays of cosmic microwave background polarimeters based on transition-edge sensors. Using the last design we demonstrated multiplexed readout of prototype polarimeters with the

  5. 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.

  6. 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.

  7. Non-Ionizing Radiation Used in Microwave Ovens

    Science.gov (United States)

    ... in Microwave Ovens Non-Ionizing Radiation Used in Microwave Ovens Explore the interactive, virtual community of RadTown USA ! ... learn more About Non-Ionizing Radiation Used in Microwave Ovens Microwave Oven. Microwave ovens use electromagnetic waves that ...

  8. Microwave-Assisted Preparation of High Entropy Alloys

    Directory of Open Access Journals (Sweden)

    Paolo Veronesi

    2015-10-01

    Full Text Available Microwaves at the ISM (Industrial, Scientific and Medical, reserved internationally frequency of 2450 or 5800 MHz have been used to prepare FeCoNiCuAl, FeCrNiTiAl and FeCoCrNiAl2.5 high entropy alloys by direct heating of pressed mixtures of metal powders. The aim of this work is to explore a new microwave-assisted near-net-shape technology, using a powder metallurgy approach for the preparation of high entropy alloys, able to overcome the limits of current melting technologies (defects formation or solid state ones (time demanding. High entropy alloy compositions have been selected so as to comprise at least one ferromagnetic element and one highly reactive couple, like Ni-Al, Ti-Al, Co-Al or Fe-Al. Results show that direct microwave heating of the powder precursors occurs, and further heating generation is favored by the ignition of exothermal reactions in the load. Microwaves have been applied both for the ignition and sustaining of such reactions, showing that by the proposed technique, it is possible to control the cooling rate of the newly-synthesized high entropy alloys. Results showed also that microwave heating in predominant magnetic field regions of the microwave applicator is more effective at controlling the cooling rate. The herein proposed microwave-assisted powder metallurgy approach is suitable to retain the shape of the load imparted during forming by uniaxial pressing. The homogeneity of the prepared high entropy alloys in all cases was good, without the dendritic segregation typical of arc melting, even if some partially-unreacted powders were detected in the samples.

  9. 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...

  10. Evaluating the Impact of Atmospheric Infrared Sounder (AIRS) Data On Convective Forecasts

    Science.gov (United States)

    Kozlowski, Danielle; Zavodsky, Bradley

    2011-01-01

    The Short-term Prediction Research and Transition Center (SPoRT) is a collaborative partnership between NASA and operational forecasting partners, including a number of National Weather Service (NWS) offices. SPoRT provides real-time NASA products and capabilities to its partners to address specific operational forecast challenges. The mission of SPoRT is to transition observations and research capabilities into operations to help improve short-term weather forecasts on a regional scale. Two areas of focus are data assimilation and modeling, which can to help accomplish SPoRT's programmatic goals of transitioning NASA data to operational users. Forecasting convective weather is one challenge that faces operational forecasters. Current numerical weather prediction (NWP) models that operational forecasters use struggle to properly forecast location, timing, intensity and/or mode of convection. Given the proper atmospheric conditions, convection can lead to severe weather. SPoRT's partners in the National Oceanic and Atmospheric Administration (NOAA) have a mission to protect the life and property of American citizens. This mission has been tested as recently as this 2011 severe weather season, which has seen more than 300 fatalities and injuries and total damages exceeding $10 billion. In fact, during the three day period from 25-27 April, 1,265 storms reports (362 tornado reports) were collected making this three day period one of most active in American history. To address the forecast challenge of convective weather, SPoRT produces a real-time NWP model called the SPoRT Weather Research and Forecasting (SPoRT-WRF), which incorporates unique NASA data sets. One of the NASA assets used in this unique model configuration is retrieved profiles from the Atmospheric Infrared Sounder (AIRS).The goal of this project is to determine the impact that these AIRS profiles have on the SPoRT-WRF forecasts by comparing to a current operational model and a control SPoRT-WRF model

  11. Radar sensitivity and antenna scan pattern study for a satellite-based Radar Wind Sounder (RAWS)

    Science.gov (United States)

    Stuart, Michael A.

    1992-01-01

    Modeling global atmospheric circulations and forecasting the weather would improve greatly if worldwide information on winds aloft were available. Recognition of this led to the inclusion of the LAser Wind Sounder (LAWS) system to measure Doppler shifts from aerosols in the planned for Earth Observation System (EOS). However, gaps will exist in LAWS coverage where heavy clouds are present. The RAdar Wind Sensor (RAWS) is an instrument that could fill these gaps by measuring Doppler shifts from clouds and rain. Previous studies conducted at the University of Kansas show RAWS as a feasible instrument. This thesis pertains to the signal-to-noise ratio (SNR) sensitivity, transmit waveform, and limitations to the antenna scan pattern of the RAWS system. A dop-size distribution model is selected and applied to the radar range equation for the sensitivity analysis. Six frequencies are used in computing the SNR for several cloud types to determine the optimal transmit frequency. the results show the use of two frequencies, one higher (94 GHz) to obtain sensitivity for thinner cloud, and a lower frequency (24 GHz) to obtain sensitivity for thinner cloud, and a lower frequency (24 GHz) for better penetration in rain, provide ample SNR. The waveform design supports covariance estimation processing. This estimator eliminates the Doppler ambiguities compounded by the selection of such high transmit frequencies, while providing an estimate of the mean frequency. the unambiguous range and velocity computation shows them to be within acceptable limits. The design goal for the RAWS system is to limit the wind-speed error to less than 1 ms(exp -1). Due to linear dependence between vectors for a three-vector scan pattern, a reasonable wind-speed error is unattainable. Only the two-vector scan pattern falls within the wind-error limits for azimuth angles between 16 deg to 70 deg. However, this scan only allows two components of the wind to be determined. As a result, a technique is

  12. KAGUYA Lunar Radar Sounder (LRS) observation of lunar surface echo and its calibration

    Science.gov (United States)

    Kobayashi, Takao; Ryeol Lee, Seung

    2015-04-01

    Lunar Radar Sounder (LRS) is an HF radar of which the center frequency of transmitted pulse is 5 MHz. LRS was installed to KAGUYA which flew to the Moon in 2007. During the operation period of 19 months, LRS performed radar sounding observation from the orbit at the nominal altitude of 100 km to cover whole surface of the Moon with its foot print. The total number of LRS observations (pulse transmissions) exceeded 10^8. We extracted the nadir surface echo out of each observation which made a surface echo map of the Moon, i.e. a mosaic image of the Moon of an HF frequency (5 MHz). The observed surface echoes carry information regarding lunar surface and that of shallow subsurface (near-surface) whose depth scale is smaller than the range resolution of the LRS (~ 150 m in vacuum). An inversion algorithm is applied to extract such information. However, inversion algorithms often assume a simple model of Fresnel reflection. One should remove the effect of surface roughness from the LRS data before practicing inversion. For this purpose, we carried out simulation of LRS observation to evaluate the surface roughness effect on the LRS data quantitatively. The simulation is based on Kirchhoff approximation theory. Digital Elevation Model (DEM) of KAGUYA Terrain Camera (TC) mission was used in the simulation to simulate the actual lunar terrain. LRS observation simulation was performed in the range from -90 to 70 degrees in longitude and in the range from -30 to 70 degrees in latitude at every 0.1 degree interval in both directions. The simulation revealed 1) LRS surface echo observation is sensible to the surface terrain: even wrinkle ridges and small craters are well recognized in the mosaic image of simulation surface echo map. 2) Little difference was found in the mosaic image of an old mare surface and a young mare surface. 3) However, apparent difference was found in the shape of the distribution functions of echo intensity of an old mare surface and a young mare

  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. A multi-sensor data-driven methodology for all-sky passive microwave inundation retrieval

    Science.gov (United States)

    Takbiri, Zeinab; Ebtehaj, Ardeshir M.; Foufoula-Georgiou, Efi

    2017-06-01

    We present a multi-sensor Bayesian passive microwave retrieval algorithm for flood inundation mapping at high spatial and temporal resolutions. The algorithm takes advantage of observations from multiple sensors in optical, short-infrared, and microwave bands, thereby allowing for detection and mapping of the sub-pixel fraction of inundated areas under almost all-sky conditions. The method relies on a nearest-neighbor search and a modern sparsity-promoting inversion method that make use of an a priori dataset in the form of two joint dictionaries. These dictionaries contain almost overlapping observations by the Special Sensor Microwave Imager and Sounder (SSMIS) on board the Defense Meteorological Satellite Program (DMSP) F17 satellite and the Moderate Resolution Imaging Spectroradiometer (MODIS) on board the Aqua and Terra satellites. Evaluation of the retrieval algorithm over the Mekong Delta shows that it is capable of capturing to a good degree the inundation diurnal variability due to localized convective precipitation. At longer timescales, the results demonstrate consistency with the ground-based water level observations, denoting that the method is properly capturing inundation seasonal patterns in response to regional monsoonal rain. The calculated Euclidean distance, rank-correlation, and also copula quantile analysis demonstrate a good agreement between the outputs of the algorithm and the observed water levels at monthly and daily timescales. The current inundation products are at a resolution of 12.5 km and taken twice per day, but a higher resolution (order of 5 km and every 3 h) can be achieved using the same algorithm with the dictionary populated by the Global Precipitation Mission (GPM) Microwave Imager (GMI) products.

  15. A multi-sensor data-driven methodology for all-sky passive microwave inundation retrieval

    Directory of Open Access Journals (Sweden)

    Z. Takbiri

    2017-06-01

    Full Text Available We present a multi-sensor Bayesian passive microwave retrieval algorithm for flood inundation mapping at high spatial and temporal resolutions. The algorithm takes advantage of observations from multiple sensors in optical, short-infrared, and microwave bands, thereby allowing for detection and mapping of the sub-pixel fraction of inundated areas under almost all-sky conditions. The method relies on a nearest-neighbor search and a modern sparsity-promoting inversion method that make use of an a priori dataset in the form of two joint dictionaries. These dictionaries contain almost overlapping observations by the Special Sensor Microwave Imager and Sounder (SSMIS on board the Defense Meteorological Satellite Program (DMSP F17 satellite and the Moderate Resolution Imaging Spectroradiometer (MODIS on board the Aqua and Terra satellites. Evaluation of the retrieval algorithm over the Mekong Delta shows that it is capable of capturing to a good degree the inundation diurnal variability due to localized convective precipitation. At longer timescales, the results demonstrate consistency with the ground-based water level observations, denoting that the method is properly capturing inundation seasonal patterns in response to regional monsoonal rain. The calculated Euclidean distance, rank-correlation, and also copula quantile analysis demonstrate a good agreement between the outputs of the algorithm and the observed water levels at monthly and daily timescales. The current inundation products are at a resolution of 12.5 km and taken twice per day, but a higher resolution (order of 5 km and every 3 h can be achieved using the same algorithm with the dictionary populated by the Global Precipitation Mission (GPM Microwave Imager (GMI products.

  16. Microwave absorbing properties of activated carbon fibre polymer ...

    Indian Academy of Sciences (India)

    Airworthiness Certification Technology Research and Management Centre, Civil Aviation University of China,. Tianjin 300300, P.R. China. †School of Materials Science and Engineering, Tianjin University, Tianjin 300072, P.R. China. MS received 10 August 2009; revised 22 January 2010. Abstract. Microwave absorption of ...

  17. Diamond like carbon coatings deposited by microwave plasma CVD ...

    Indian Academy of Sciences (India)

    WINTEC

    Laser and Plasma Technology Division,. Bhabha Atomic Research Centre, Mumbai 400 085, India. MS received 3 May 2007. Abstract. Diamond-like carbon (DLC) films were deposited by microwave assisted chemical vapour deposi- tion system using d.c. bias voltage ranging from –100 V to –300 V. These films were ...

  18. 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.

  19. Spherical microwave confinement and ball lightning

    Science.gov (United States)

    Robinson, William Richard

    This dissertation presents the results of research done on unconventional energy technologies from 1995 to 2009. The present civilization depends on an infrastructure that was constructed and is maintained almost entirely using concentrated fuels and ores, both of which will run out. Diffuse renewable energy sources rely on this same infrastructure, and hence face the same limitations. I first examined sonoluminescence directed toward fusion, but demonstrated theoretically that this is impossible. I next studied Low Energy Nuclear Reactions and developed methods for improving results, although these have not been implemented. In 2000, I began Spherical Microwave Confinement (SMC), which confines and heats plasma with microwaves in a spherical chamber. The reactor was designed and built to provide the data needed to investigate the possibility of achieving fusion conditions with microwave confinement. A second objective was to attempt to create ball lightning (BL). The reactor featured 20 magnetrons, which were driven by a capacitor bank and operated in a 0.2 s pulse mode at 2.45 GHz. These provided 20 kW to an icosahedral array of 20 antennas. Video of plasmas led to a redesign of the antennas to provide better coupling of the microwaves to the plasma. A second improvement was a grid at the base of the antennas, which provided corona electrons and an electric field to aid quick formation of plasmas. Although fusion conditions were never achieved and ball lightning not observed, experience gained from operating this basic, affordable system has been incorporated in a more sophisticated reactor design intended for future research. This would use magnets that were originally planned. The cusp geometry of the magnetic fields is suitable for electron cyclotron resonance in the same type of closed surface that in existing reactors has generated high-temperature plasmas. Should ball lightning be created, it could be a practical power source with nearly ideal

  20. Identification of natural plasma emissions observed close to the plasmapause by the Cluster-Whisper relaxation sounder

    Directory of Open Access Journals (Sweden)

    P. Canu

    Full Text Available We use the data collected by the Whisper instrument onboard the Cluster spacecraft for a first test of its capabilities in the identification of the natural plasma waves observed in the Earth’s magnetosphere. The main signatures observed at the plasma frequency, upper hybrid frequency, and electron Bernstein modes were often difficult to be reliably recognized on previous missions. We use here the characteristic frequencies provided by the resonances triggered by the relaxation sounder of Whisper to identify with good confidence the various signatures detected in the complex wave spectra collected close to the plasmapause. Coupled with the good sensitivity, frequency and time resolution of Whisper, the resonances detected by the sounder allow one to precisely spot these natural emissions. This first analysis seems to confirm the interpretation of Geos observations: the natural emissions observed in Bernstein modes above the plasma frequency, now widely observed onboard Cluster, are not modeled by a single Maxwellian electrons distribution function. Therefore, multi-temperature electron distribution functions should be considered.

    Key words. Space plasma physics (active perturbation experiments; waves and instabilities; instrument and techniques

  1. More Experiments with Microwave Ovens

    Science.gov (United States)

    Vollmer, Michael; Mollmann, Klaus-Peter; Karstadt, Detlef

    2004-01-01

    Microwave ovens can be used to perform exciting demonstrations that illustrate a variety of physics topics. Experiments discussed here show superheating, visualize the inhomogeneous heating that takes place in a microwave and also show how to use a mobile phone to detect radiation leaking from the oven. Finally eggs can give some spectacular…

  2. 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,

  3. Microwave drying of wood strands

    Science.gov (United States)

    Guanben Du; Siqun Wang; Zhiyong Cai

    2005-01-01

    Characteristics of microwave drying of wood strands with different initial moisture contents and geometries were investigated using a commercial small microwave oven under different power inputs. Temperature and moisture changes along with the drying efficiency were examined at different drying scenarios. Extractives were analyzed using gas chromatography=mass...

  4. 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)

  5. 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...... fabricated on silicon-on-insulator chips and have advantages of compactness and capability to integrate with electronics....

  6. Microstrip microwave band gap structures

    Indian Academy of Sciences (India)

    Microwave band gap structures exhibit certain stop band characteristics based on the periodicity, impedance contrast and effective refractive index contrast. These structures though formed in one-, two- and three-dimensional periodicity, are huge in size. In this paper, microstrip-based microwave band gap structures are ...

  7. Micro-Coplanar Striplines: New Transmission Media for Microwave Applications

    Science.gov (United States)

    Goverdhanam, Kavita; Simons, Rainee N.; Katehi, Linda P. B.

    1998-01-01

    In this paper a new transmission line for microwave applications, referred to here as the Micro-Coplanar Stripline (MCPS), is introduced. The propagation characteristics, such as, characteristic impedance (Z(sub 0) and effective dielectric constant (epsilon eff) for a range of MCPS geometries have been modeled using the Finite Difference Time Domain (FDTD) Technique and presented here. Also, preliminary experimental results on the performance of an MCP-Microstrip transition and an MCPS-fed patch antenna are presented. The results indicate several potential applications of the MCPS line in microwave integrated circuit technology.

  8. 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...

  9. 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

  10. Microwave power coupling with electron cyclotron resonance ...

    Indian Academy of Sciences (India)

    The effect of microwave power coupling to the plasma was studied by varying the microwave power. ... plasma is produced by the interaction of microwave radiation, in the presence of appro- priate magnetic field ... microwaves are used in resonant mode to couple the electromagnetic energy to the plasma for generating ...

  11. Sounder PEATE MetOp-A IASI Cloud Calibration Subset Observations V10 (SPCSMA2D) at GES DISC

    Data.gov (United States)

    National Aeronautics and Space Administration — CalSub product files are constructed from calibrated radiance files (infrared and microwave) from either the SNPP, Aqua or MetOP-A/B. Nominally one logical file is...

  12. Sounder PEATE MetOp-A IASI Random Calibration Subset Observations V10 (SPCSMA4D) at GES DISC

    Data.gov (United States)

    National Aeronautics and Space Administration — CalSub product files are constructed from calibrated radiance files (infrared and microwave) from either the SNPP, Aqua or MetOP-A/B. Nominally one logical file is...

  13. Sounder PEATE SNPP CrIS Cloud Calibration Subset Observations V10 (SPCSNP2D) at GES DISC

    Data.gov (United States)

    National Aeronautics and Space Administration — CalSub product files are constructed from calibrated radiance files (infrared and microwave) from either the SNPP, Aqua or MetOP-A/B. Nominally one logical file is...

  14. Sounder PEATE MetOp-A IASI Clear Calibration Subset Observations V10 (SPCSMA1D) at GES DISC

    Data.gov (United States)

    National Aeronautics and Space Administration — CalSub product files are constructed from calibrated radiance files (infrared and microwave) from either the SNPP, Aqua or MetOP-A/B. Nominally one logical file is...

  15. MLS and CALIOP Cloud Ice Measurements in the Upper Troposphere: A Constraint from Microwave on Cloud Microphysics

    Science.gov (United States)

    Wu, Dong L.; Lambert, Alyn; Read, William G.; Eriksson, Patrick; Gong, Jie

    2014-01-01

    This study examines the consistency and microphysics assumptions among satellite ice water content (IWC) retrievals in the upper troposphere with collocated A-Train radiances from Microwave Limb Sounder (MLS) and lidar backscatters from Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP). For the cases in which IWC values are small (less than 10mg m(exp-23)), the cloud ice retrievals are constrained by both MLS 240- and 640- GHz radiances and CALIOP 532-nm backscatter beta(532). From the observed relationships between MLS cloud-induced radiance T(sub cir) and the CALIOP backscatter integrated gamma532 along the MLS line of sight, an empirical linear relation between cloud ice and the lidar backscatter is found: IWC/beta532=0.58+/-0.11. This lidar cloud ice relation is required to satisfy the cloud ice emission signals simultaneously observed at microwave frequencies, in which ice permittivity is relatively well known. This empirical relationship also produces IWC values that agree well with the CALIOP, version 3.0, retrieval at values, less than 10mg m(exp-3). Because the microphysics assumption is critical in satellite cloud ice retrievals, the agreement found in the IWC-beta532 relationships increase fidelity of the assumptions used by the lidar and microwave techniques for upper-tropospheric clouds.

  16. 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 ...

  17. Vibration measurement on large structures by microwave remote sensing

    Science.gov (United States)

    Gentile, Carmelo

    2012-06-01

    Recent advances in radar techniques and systems have led to the development of microwave interferometers, suitable for the non-contact vibration monitoring of large structures. In the first part of the paper, the main techniques adopted in microwave remote sensing are described, so that advantages and potential issues of these techniques are addressed and discussed. Subsequently, the results of past and recent tests of full-scale structures are presented, in order to demonstrate the reliability and accuracy of microwave remote sensing; furthermore, the simplicity of use of the radar technology is exemplified in practical cases, where the access with conventional techniques is uneasy or even hazardous, such as the stay cables of cable-stayed bridges.

  18. Extraction of lotus fibres from lotus stems under microwave irradiation.

    Science.gov (United States)

    Cheng, Cheng; Guo, Ronghui; Lan, Jianwu; Jiang, Shouxiang

    2017-09-01

    An efficient technology for preparing lotus fibres under microwave irradiation was developed. The lotus fibres were characterized by scanning electron microscopy, Fourier transform infrared spectrometry, X-ray diffraction and thermogravimetry. Lotus fibres prepared are a kind of hollow fibres which are composed of a superfine fibre and an external shell. The effect of the treatment time with hydrogen peroxide under microwave irradiation on components, whiteness, moisture regain, removal rate of impurities, fineness, tensile strength and breaking elongation of lotus fibres was investigated. The results show that the cellulose content in lotus fibres increases with increase in treatment time. Whiteness and moisture regain of lotus fibres increase with increase in treatment time with hydrogen peroxide. The removal rate of impurities and the fineness of lotus fibres are improved after they are treated with hydrogen peroxide. Microwave irradiation is supposed to be an efficient method for producing lotus fibres.

  19. A method for comparing properties of cirrus clouds in global climate models with those retrieved from IR sounder satellite observations

    Energy Technology Data Exchange (ETDEWEB)

    Hendricks, Johannes; Emde, Claudia [DLR Deutsches Zentrum fuer Luft- und Raumfahrt e.V., Oberpfaffenhofen (Germany). Inst. fuer Physik der Atmosphaere; Falb, Andreas [DLR Deutsches Zentrum fuer Luft- und Raumfahrt e.V., Oberpfaffenhofen (Germany). Inst. fuer Physik der Atmosphaere; Bayerisches Landesamt fuer Umwelt, Augsburg (Germany); Stubenrauch, Claudia J. [Ecole Polytechnique, Palaiseau (France). Lab. de Meteorologie Dynamique

    2010-12-15

    A methodology to compare cloud properties simulated by global climate models with those retrieved from observations by satellite-based infrared (IR) sounders has been developed. The relatively high spectral resolution in the CO{sub 2} absorption band of these instruments leads to especially reliable cirrus properties, day and night. Additionally, bulk microphysical properties can be retrieved for semi-transparent cirrus, based on the observed spectral emissivity differences between 8 and 11 {mu}m. The particular intention of this study is to compare macro- and microphysical properties of high cloudiness as represented by the model simulations and the satellite data. For this purpose, a method has been developed to process the model output to be comparable to the satellite measurements, as in other observational simulator packages (for example the ISCCP-simulator). This simulator method takes into account (i) the differences in horizontal resolution of the model and the observations, (ii) the specific observation time windows, (iii) the determination of the pressure of a cloud system, identified with the pressure at the middle of the uppermost cloud, and (iv) the selection of high clouds with specific cloud optical thickness ranges for the microphysical property retrieval using IR sounder data. Applying this method to simulations by the global climate model ECHAM and TOVS satellite observations has important effects. The frequency of high clouds selected from the model output by using the method is significantly smaller than the total frequency of high cloudiness in the model. Largest differences occur around the equator where the zonal mean frequency of high cloudiness is reduced by about 30 % (relative change). The selection method is essential for the comparison of modelled and observed microphysical properties of high clouds. The selection of high clouds from the ECHAM simulation according to the optical thickness range of the TOVS data results in a reduction of

  20. Inferring the acoustic dead-zone volume by split-beam echo sounder with narrow-beam transducer on a noninertial platform.

    Science.gov (United States)

    Patel, Ruben; Pedersen, Geir; Ona, Egil

    2009-02-01

    Acoustic measurement of near-bottom fish with a directional transducer is generally problematical because the powerful bottom echo interferes with weaker echoes from fish within the main lobe but at greater ranges than that of the bottom. The volume that is obscured is called the dead zone. This has already been estimated for the special case of a flat horizontal bottom when observed by an echo sounder with a stable vertical transducer beam [Ona, E., and Mitson, R. B. (1996). ICES J. Mar. Sci. 53, 677-690]. The more general case of observation by a split-beam echo sounder with a transducer mounted on a noninertial platform is addressed here. This exploits the capability of a split-beam echo sounder to measure the bottom slope relative to the beam axis and thence to allow the dead-zone volume over a flat but sloping bottom to be estimated analytically. The method is established for the Simrad EK60 scientific echo sounder, with split-beam transducers operating at 18, 38, 70, 120, and 200 kHz. It is validated by comparing their estimates of seafloor slope near the Lofoten Islands, N67-70, with simultaneous measurements made by two hydrographic multibeam sonars, the Simrad EM100295 kHz and EM30030 kHz systems working in tandem.

  1. Analysis of heat and mass transfer during microwave drying of food products

    Directory of Open Access Journals (Sweden)

    A. K. Haghi

    2008-09-01

    Full Text Available Microwave (MW drying is a rapid dehydration technique that can be applied to specific foods. Increasing concerns over product quality and production costs have motivated the researchers to investigate and the industry to adopt microwave drying technology. The advantages of microwave drying include the following: shorter drying time, improved product quality, and flexibility in producing a wide variety of dried products. Drying is influenced by heat and mass transfer between drying airflow and product, as well as the complex moisture transport processes which take place in the product.. This paper presents an analytical approach for the drying of potato. The laws of moisture content change in the food product as a function of mass transfer are used for the theoretical approach. The study gives a brief description of efforts made to obtain basic drying parameters under different microwave drying conditions. This computational method can be used as a tool for microwave drying of potato slabs more efficiency.

  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. 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.

    1985-01-01

    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 development 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. 9 references.

  4. The Study of Microwave and Electric Hybrid Sintering Process of AZO Target

    Directory of Open Access Journals (Sweden)

    Ling-yun Han

    2016-01-01

    Full Text Available We simulated the microwave sintering of ZnO by 3D modelling. A large-size Al-doped ZnO (AZO green ceramic compact was prepared by slurry casting. Through studying the microwave and electric hybrid sintering of the green compact, a relative density of up to 98.1% could be obtained by starting microwave heating at 1200°C and increasing the power 20 min later to 4 kW for an AZO ceramic target measuring 120 × 240 × 12 mm. The resistivity of AZO targets sintered with microwave assistance was investigated. The energy consumption of sintering could be greatly reduced by this heating method. Until now, few studies have been reported on the microwave and electric hybrid sintering of large-size AZO ceramic targets. This research can aid in developing sintering technology for large-size high-quality oxide ceramic targets.

  5. Discrimination of fish layers using the three-dimensional information obtained by a split-beam echo-sounder

    DEFF Research Database (Denmark)

    Pedersen, Jens

    1996-01-01

    This study attempts to illustrate the three-dimensional pattern of a ''pelagic'' and a ''benthic'' layer of fish using single- target information obtained using a split-beam echo-sounder. Parameters such as the nearest-neighbour distance and separation angle between the two nearest neighbours...... around a reference fish were used to discriminate between the two layers. The parameters estimated were found to be significantly different between the two layers. The mean nearest-neighbour distance estimated was 6.3 m and 5.8 m for the ''benthic'' and the ''pelagic'' layers, respectively, and the mean....... It was concluded that illustration and discrimination between the two layers was possible using parameters related to the relative position of targets. (C) 1996 International Council For the Exploration of the Sea....

  6. Detection of Intact Lava Tubes at Marius Hills on the Moon by SELENE (Kaguya) Lunar Radar Sounder

    Science.gov (United States)

    Kaku, T.; Haruyama, J.; Miyake, W.; Kumamoto, A.; Ishiyama, K.; Nishibori, T.; Yamamoto, K.; Crites, Sarah T.; Michikami, T.; Yokota, Y.; Sood, R.; Melosh, H. J.; Chappaz, L.; Howell, K. C.

    2017-10-01

    Intact lunar lava tubes offer a pristine environment to conduct scientific examination of the Moon's composition and potentially serve as secure shelters for humans and instruments. We investigated the SELENE Lunar Radar Sounder (LRS) data at locations close to the Marius Hills Hole (MHH), a skylight potentially leading to an intact lava tube, and found a distinctive echo pattern exhibiting a precipitous decrease in echo power, subsequently followed by a large second echo peak that may be evidence for the existence of a lava tube. The search area was further expanded to 13.00-15.00°N, 301.85-304.01°E around the MHH, and similar LRS echo patterns were observed at several locations. Most of the locations are in regions of underground mass deficit suggested by GRAIL gravity data analysis. Some of the observed echo patterns are along rille A, where the MHH was discovered, or on the southwest underground extension of the rille.

  7. Stratigraphy and structural evolution of southern Mare Serenitatis - A reinterpretation based on Apollo Lunar Sounder Experiment data

    Science.gov (United States)

    Sharpton, V. L.; Head, J. W., III

    1983-01-01

    Two subsurface reflecting horizons have been detected by the Apollo Lunar Sounder Experiment (ALSE) in the southern Mare Serenitatis which appear to be regolith layers more than 2 m thick, and are correlated with major stratigraphic boundaries in the southeastern Mare Serenitatis. The present stratigraphic boundaries in the southeastern Mare Serenitatis. The present analysis implies that the lower horizon represents the interface between the earliest mare unit and the modified Serenitatis basin material below. The depth of volcanic fill within Serenitatis is highly variable, with an average thickness of mare basalts under the ALSE ground track of 1.6 km. Comparisons with the Orientale basin topography suggests that a major increaae in load thickness could occur a few km basinward of the innermost extent of the traverse. The history of volcanic infilling of Mare Serenitatis was characterized by three major episodes of volcanism.

  8. Wide spectrum microwave pulse measurement

    Energy Technology Data Exchange (ETDEWEB)

    King, R.J.

    1986-01-01

    Various techniques are postulated as diagnostics for wide band microwave pulses. The diagnostics include determinations of both the instantaneous amplitude and the frequency content of one-shot pulses. 6 refs., 11 figs. (WRF)

  9. Scanning Microwave Induced Acoustic Tomography

    National Research Council Canada - National Science Library

    Wang, Lihong V

    2001-01-01

    .... Cancerous breast tissues are found to be 2-5 times more strongly absorbing than surrounding normal breast tissues in the microwave, which has been attributed to an increase in bound water and sodium...

  10. Real-time Data Processing and Visualization for the Airborne Scanning High-resolution Interferometer Sounder (S-HIS)

    Science.gov (United States)

    Taylor, J. K.; Revercomb, H. E.; Hoese, D.; Garcia, R. K.; Smith, W. L.; Weisz, E.; Tobin, D. C.; Best, F. A.; Knuteson, R. O.; Sullivan, D. V.; Barnes, C. M.; Van Gilst, D. P.

    2015-12-01

    The Hurricane and Severe Storm Sentinel (HS3) is a five-year NASA mission targeted to enhance the understanding of the formation and evolution of hurricanes in the Atlantic basin. Measurements were made from two NASA Global Hawk Unmanned Aircraft Systems (UAS) during the 2012 through 2014 hurricane seasons, with flights conducted from the NASA Wallops Flight Facility. The Global Hawk aircraft are capable of high altitude flights with durations of up to 30 hours, which allow extensive observations over distant storms, not typically possible with manned aircraft. The two NASA Global Hawks were equipped with instrument suites to study the storm environment, and inner core structure and processes, respectively. The Scanning High-resolution Interferometer Sounder (S-HIS), designed and built by the University of Wisconsin (UW) Space Science and Engineering Center (SSEC), measures emitted thermal radiation at high spectral resolution between 3.3 and 18 microns. The radiance measurements are used to obtain temperature and water vapor profiles of the Earth's atmosphere. The S-HIS spatial resolution is 2 km at nadir, across a 40 km ground swath from a nominal altitude of 20 kilometers. Since 1998, the S-HIS has participated in 33 field campaigns and has proven to be extremely dependable, effective, and highly accurate. It has flown on the NASA ER-2, DC-8, Proteus, WB-57, and Global Hawk airborne platforms. The UW S-HIS infrared sounder instrument is equipped with a real-time ground data processing system capable of delivering atmospheric profiles, radiance data, and engineering status to mission support scientists - all within less than one minute from the time of observation. This ground data processing system was assembled by a small team using existing software and proven practical techniques similar to a satellite ground system architecture. This summary outlines the design overview for the system and illustrates the data path, content, and outcomes.

  11. Microwave remote sensing from space

    OpenAIRE

    Carver, Keith R.; Elachi, Charles; Ulaby, Fawwaz T.

    1985-01-01

    Spaceborne microwave remote sensors provide perspectives of the earth surface and atmosphere which are of unique value in scientific studies of geomorphology, oceanic waves and topography, atmospheric water vapor and temperatures, vegetation classification and stress, ice types and dynamics, and hydrological characteristics. Microwave radars and radiometers offer enhanced sensitivities to the geometrical characteristics of the earth's surface and its cover, to water in all its forms--soil and...

  12. 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.

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

    Science.gov (United States)

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

    2017-11-01

    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.

  14. 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.

  15. Mediterranean hurricanes: large-scale environment and convective and precipitating areas from satellite microwave observations

    Directory of Open Access Journals (Sweden)

    C. Claud

    2010-10-01

    Full Text Available Subsynoptic scale vortices that have been likened to tropical cyclones or polar lows (medicanes are occasionally observed over the Mediterranean Sea. Generated over the sea, they are usually associated with strong winds and heavy precipitation and thus can be highly destructive in islands and costal areas. Only an accurate forecasting of such systems could mitigate these effects. However, at the moment, the predictability of these systems remains limited.

    Due to the scarcity of conventional observations, use is made of NOAA/MetOp satellite observations, for which advantage can be taken of the time coverage differences between the platforms that carry it, to give a very complete temporal description of the disturbances. A combination of AMSU-B (Advanced Microwave Sounding Unit-B/MHS (Microwave Humidity Sounder observations permit to investigate precipitation associated with these systems while coincident AMSU-A (Advanced Microwave Sounding Unit-A observations give insights into the larger synoptic-scale environment in which they occur.

    Three different cases (in terms of intensity, location, trajectory, duration, and periods of the year – May, September and December, respectively were investigated. Throughout these time periods, AMSU-A observations show that the persisting deep outflow of cold air over the sea together with an upper-level trough upstream constituted a favourable environment for the development of medicanes. AMSU-B/MHS based diagnostics show that convection and precipitation areas are large in the early stage of the low, but significantly reduced afterwards. Convection is maximum just after the upper-level trough, located upstream of cold mid-tropospheric air, reached its maximum intensity and acquired a cyclonic orientation.

  16. Microwave Quantum Illumination

    Science.gov (United States)

    2016-07-29

    Cambridge, Massachusetts 02138, USA 3QKD Corp., 60 St. George St., Toronto, M5S 3G4, Canada 4School of Science and Technology, University of Camerino ... Camerino , Macerata 62032, Italy 5Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA

  17. 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

  18. 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.

  19. 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.

  20. Global relation between microwave satellite vegetation products and vegetation productivity

    Science.gov (United States)

    Teubner, Irene E.; Forkel, Matthias; Jung, Martin; Miralles, Diego G.; Dorigo, Wouter A.

    2017-04-01

    The occurrence of unfavourable environmental conditions like droughts commonly reduces the photosynthetic activity of ecosystems and, hence, their potential to take up carbon from the atmosphere. Ecosystem photosynthetic activity is commonly determined using remote sensing observations in the optical domain, which however have limitations particularly in regions of frequent cloud cover, e.g. the tropics. In this study, we explore the potential of vegetation optical depth (VOD) from microwave satellite observations as an alternative source for assessing vegetation productivity. VOD serves as an estimate for vegetation density and water content, which has an impact on plant physiological processes and hence should potentially provide a link to gross primary production (GPP). However, to date, it is unclear how microwave-retrieved VOD data and GPP data are related. We compare seasonal dynamics and anomalies of VOD retrievals from different satellite sensors and microwave frequencies with site level and global GPP estimates. We use VOD observations from active (ASCAT) and passive microwave sensors (AMSR-E, SMOS). We include eddy covariance measurements from the FLUXNET2015 dataset to assess the VOD products at site level. For a global scale analysis, we use the solar-induced chlorophyll fluorescence (SIF) observations from GOME-2 as a proxy for GPP and the FLUXCOM GPP product, which presents an upscaling of site measurements based on remote sensing data. Our results demonstrate that in general a good agreement between VOD and GPP or SIF exists. However, the strength of these relations depends on the microwave frequency, land cover type, and the time within the growing season. Correlations between anomalies of VOD and GPP or SIF support the assumption that microwave-derived VOD can be used to monitor vegetation productivity dynamics. The study is performed as part of the EOWAVE project funded by the Vienna University of Technology (http://eowave.geo.tuwien.ac.at/) and

  1. Intersunspot Microwave Sources

    Science.gov (United States)

    Bakunina, I. A.; Melnikov, V. F.; Solov'ev, A. A.; Abramov-Maximov, V. E.

    2015-01-01

    We studied a number of solar active regions using two-dimensional spatially resolved microwave observations. Data from the Nobeyama Radioheliograph and the Siberian Solar Radio Telescope together with observations by the Michelson Doppler Imager (MDI) onboard the Solar and Heliospheric Observatory (SOHO) have allowed us to identify long-lived intersunspot sources (ISSs) in most of the investigated active regions. Their centers are often located above the line-of-sight magnetic field inversion line that separates the leading and following polarities of a full active region (first type of ISS) or above the inversion line that separates magnetic polarities inside of a complex of sunspots (second type of ISS). ISSs of the first type are extended and, in general, they are sources of bremsstrahlung emission. ISSs of the second type are compact and are, most likely, sources of gyroresonance or gyrosynchrotron emission. We propose a qualitative model involving three types of magnetic connectivity to explain how long-lasting ISSs may be generated.

  2. Novel Phase Noise Reduction Method for CPW‐Based Microwave Oscillator Circuit Utilizing a Compact Planar Helical Resonator

    National Research Council Canada - National Science Library

    Hwang, Cheol Gyu; Myung, Noh Hoon

    2006-01-01

    This letter describes a compact printed helical resonator and its application to a microwave oscillator circuit implemented in coplanar waveguide (CPW) technology. The high quality (Q)‐factor and spurious...

  3. Methods of microwave fixation for microscopy. A review of research and clinical applications: 1970-1992.

    Science.gov (United States)

    Login, G R; Dvorak, A M

    1994-01-01

    Microwave fixation methods are important because excellent preservation of both cell structure and antigenicity can be attained several orders of magnitude faster than by routine chemical fixation methods. Fast and ultrafast microwave fixation have yielded significant logistic advantages over another fast fixation approach-rapid freezing at liquid helium temperatures. For example, specimens used for microwave fixation can be as large as 1 cm3 and cells can remain in suspension. We review in detail both qualitative and quantitative morphologic results obtained by using microwave fixation in sample preparation. We provide tables of biological molecules that are preserved in a variety of human and animal tissues by various microwave fixation methods for histochemistry, immunohistochemistry, cytochemistry, immunocytochemistry, and affinity labelling studies. Limitations of large cavity (e.g., household) microwave ovens often result in irreproducible fixation results. We present calibration and standardization protocols for microwave fixation in large cavity microwave ovens that emphasize a) localization of oven hot spots (i.e., high power) using a neon bulb array, b) magnetron warm-up, c) the use of a water load, d) the use of an agar-saline-Giemsa model to predict the uniformity of irradiation in small samples, e) the use of specimen containers with one dimension less than 1.5 cm, and f) fast specimen handling to prevent conductive heating artifacts after irradiation. Although microwave ovens are commonplace their unique applications in the laboratory environment require special safety considerations, which are reviewed. Advances in microwave technology are providing new means to study the structure-function relationships of cellular and biochemical activities.

  4. 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:...

  5. Student Microwave Experiments Involving the Doppler Effect.

    Science.gov (United States)

    Weber, F. Neff; And Others

    1980-01-01

    Described is the use of the Doppler Effect with microwaves in the measurement of the acceleration due to gravity of falling objects. The experiments described add to the repertoire of quantitative student microwave experiments. (Author/DS)

  6. 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...

  7. 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

  8. Sounder PEATE SNPP CrIMSS IR MW Retrieval Level 3 8-Day Observations 1 degree x 1 degree V10 (SPL3NP2N) at GES DISC

    Data.gov (United States)

    National Aeronautics and Space Administration — The Sounder PEATE Level 3 Product provides global cylindrical grids summarizing Level-2 data from a given instrument suite for one day, 8-consecutive days, or one...

  9. Sintering behavior and microwave dielectric properties of a new ...

    Indian Academy of Sciences (India)

    63

    Sintering behavior and microwave dielectric properties of a new complex perovskite: (1–x)(Sr0.3Ca0.427Nd0.182)TiO3-xSmAlO3 ceramics. JING JING QU1, FEI LIU2,*, XING WEI1, CHANG LAI YUAN3, XIAN PEI. HUANG3. 1Department of Information Engineering, Guilin University of Aerospace. Technology, Guilin 541004 ...

  10. Smelting Magnesium Metal using a Microwave Pidgeon Method

    OpenAIRE

    Yuji Wada; Satoshi Fujii; Eiichi Suzuki; Maitani, Masato M.; Shuntaro Tsubaki; Satoshi Chonan; Miho Fukui; Naomi Inazu

    2017-01-01

    Magnesium (Mg) is a lightweight metal with applications in transportation and sustainable battery technologies, but its current production through ore reduction using the conventional Pidgeon process emits large amounts of CO2 and particulate matter (PM2.5). In this work, a novel Pidgeon process driven by microwaves has been developed to produce Mg metal with less energy consumption and no direct CO2 emission. An antenna structure consisting of dolomite as the Mg source and a ferrosilicon ant...

  11. A New Inversion Routine to Produce Vertical Electron-Density Profiles from Ionospheric Topside-Sounder Data

    Science.gov (United States)

    Wang, Yongli; Benson, Robert F.

    2011-01-01

    Two software applications have been produced specifically for the analysis of some million digital topside ionograms produced by a recent analog-to-digital conversion effort of selected analog telemetry tapes from the Alouette-2, ISIS-1 and ISIS-2 satellites. One, TOPIST (TOPside Ionogram Scalar with True-height algorithm) from the University of Massachusetts Lowell, is designed for the automatic identification of the topside-ionogram ionospheric-reflection traces and their inversion into vertical electron-density profiles Ne(h). TOPIST also has the capability of manual intervention. The other application, from the Goddard Space Flight Center based on the FORTRAN code of John E. Jackson from the 1960s, is designed as an IDL-based interactive program for the scaling of selected digital topside-sounder ionograms. The Jackson code has also been modified, with some effort, so as to run on modern computers. This modification was motivated by the need to scale selected ionograms from the millions of Alouette/ISIS topside-sounder ionograms that only exist on 35-mm film. During this modification, it became evident that it would be more efficient to design a new code, based on the capabilities of present-day computers, than to continue to modify the old code. Such a new code has been produced and here we will describe its capabilities and compare Ne(h) profiles produced from it with those produced by the Jackson code. The concept of the new code is to assume an initial Ne(h) and derive a final Ne(h) through an iteration process that makes the resulting apparent-height profile fir the scaled values within a certain error range. The new code can be used on the X-, O-, and Z-mode traces. It does not assume any predefined profile shape between two contiguous points, like the exponential rule used in Jackson s program. Instead, Monotone Piecewise Cubic Interpolation is applied in the global profile to keep the monotone nature of the profile, which also ensures better smoothness

  12. 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.

  13. 21 CFR 1030.10 - Microwave ovens.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Microwave ovens. 1030.10 Section 1030.10 Food and... ovens. (a) Applicability. The provisions of this standard are applicable to microwave ovens manufactured after October 6, 1971. (b) Definitions. (1) Microwave oven means a device designed to heat, cook, or dry...

  14. Mechanical characterization of microwave sintered zinc oxide

    Indian Academy of Sciences (India)

    The mechanical characterization of microwave sintered zinc oxide disks is reported. The microwave sintering was done with a specially designed applicator placed in a domestic microwave oven operating at a frequency of 2.45 GHz to a maximum power output of 800 Watt. These samples with a wide variation of density ...

  15. 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...

  16. Microwave synthesis and mechanical characterization of functionally ...

    Indian Academy of Sciences (India)

    Skin depth of electromagnetic radiation increases with tem- perature and consequently material–microwave interaction increases with temperature. At high temperatures, efficient penetration of microwaves provides sufficient volume for material–microwave interaction and hence substantial vol- umetric heating of metal ...

  17. Geometry-based channel modelling of MIMO channels in comparison with channel sounder measurements

    OpenAIRE

    G. Del Galdo; M. Haardt; C. Schneider

    2004-01-01

    In this paper we propose a flexible geometrybased propagation model for wireless communications developed at Ilmenau University of Technology. The IlmProp comprises a geometrical representation of the environment surrounding the experiment and a precise representation of the transmitting and receiving antennas. The IlmProp is capable of simulating Multi-User MIMO scenarios and includes a complete collection of tools to analyze the synthetic channels. In order to assess...

  18. Variable frequency microwave (VFM) curing, processing of thermoset prepreg laminates. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Paulauskas, F.L.

    1996-09-30

    The objective of this work was to investigate the beneficial effect of the variable frequency microwave (VFM) technology to cure thermosetting prepreg laminates. Further, it was to investigate the interrelationship and effect on the curing process of frequency, band width, and curing time with different types of laminates. Previous studies of microwave-assisted curing of neat resins (epoxy) and unidirectional glass and carbon fiber laminates with a fixed frequency of 2.45 GHz, have shown that a substantial reduction in the curing time was obtained. Results of this earlier work indicate that the microwave-assisted curing of multidirectional glass fiber laminates also show a substantial reduction of the required curing time. This may be explained by the penetration of microwave energy directly and throughout the laminate with enhancement of the kinetics of the chemical reaction. The fixed frequency microwave radiation of 2.45 GHz has been demonstrated to be a partially acceptable method to cure unidirectional carbon fiber laminates. Multidirectional carbon fiber/epoxy laminates demonstrate a lack of coupling during the curing process. A direct curing of these laminates was not possible by microwave radiation with the experimental approach used in agreement with previous work. In addition to this short coming, the unidirectional laminate samples cured with the fixed frequency are visually nonuniform. Localized areas of darker colors (burn, hot spots, overheating) are attributed to the formation of standing waves within the microwave cavity. For this reason, the laminates are subject to proper rotation while curing through fixed frequency. The present research indicates that variable frequency microwave technology is a sound and acceptable processing method to effectively cure uni-, bi- or multi-directional thermosetting glass fiber laminates. Also, this methodology will effectively cure unidirectional thermosetting carbon fiber laminates. For all these cases, this

  19. Use of INSAT-3D sounder and imager radiances in the 4D-VAR data assimilation system and its implications in the analyses and forecasts

    Science.gov (United States)

    Indira Rani, S.; Taylor, Ruth; George, John P.; Rajagopal, E. N.

    2016-05-01

    INSAT-3D, the first Indian geostationary satellite with sounding capability, provides valuable information over India and the surrounding oceanic regions which are pivotal to Numerical Weather Prediction. In collaboration with UK Met Office, NCMRWF developed the assimilation capability of INSAT-3D Clear Sky Brightness Temperature (CSBT), both from the sounder and imager, in the 4D-Var assimilation system being used at NCMRWF. Out of the 18 sounder channels, radiances from 9 channels are selected for assimilation depending on relevance of the information in each channel. The first three high peaking channels, the CO2 absorption channels and the three water vapor channels (channel no. 10, 11, and 12) are assimilated both over land and Ocean, whereas the window channels (channel no. 6, 7, and 8) are assimilated only over the Ocean. Measured satellite radiances are compared with that from short range forecasts to monitor the data quality. This is based on the assumption that the observed satellite radiances are free from calibration errors and the short range forecast provided by NWP model is free from systematic errors. Innovations (Observation - Forecast) before and after the bias correction are indicative of how well the bias correction works. Since the biases vary with air-masses, time, scan angle and also due to instrument degradation, an accurate bias correction algorithm for the assimilation of INSAT-3D sounder radiance is important. This paper discusses the bias correction methods and other quality controls used for the selected INSAT-3D sounder channels and the impact of bias corrected radiance in the data assimilation system particularly over India and surrounding oceanic regions.

  20. Characteristics of Cylindrical Microwave Plasma Source at Low Pressure

    Science.gov (United States)

    Park, Seungil; Youn, S.; Kim, S. B.; Yoo, S. J.

    2016-10-01

    A microwave plasma source with a cylindrical resonance cavity has been proposed to generate the plasma at low pressure. This plasma source consists of magnetron, waveguide, antenna, and cavity. The microwave generating device is a commercial magnetron with 1 kW output power at the frequency of 2.45 GHz. The microwave is transmitted through the rectangular waveguide with the whistle shape, and coupled to the cavity by the slot antenna. The resonant mode of the cylindrical cavity is the TE111 mode. The operating pressure is between 0.1 Torr and 0.3 Torr with the Argon and nitrogen gas. The electron temperature and electron number density of argon plasma were measured with the optical emission spectroscopy measurement. And Ar1s5 metastable density was measured using tunable diode laser absorption spectroscopy (TDLAS). The plasma diagnostic results of a cylindrical microwave plasma source would be described in this study. This work was supported by R&D Program of ``Plasma Advanced Technology for Agriculture and Food (Plasma Farming)'' through the National Fusion Research Institute of Korea (NFRI) funded by the Government funds.

  1. 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

  2. A Microwave Plasma Closing Switch

    Science.gov (United States)

    Lock Kang, Weng; Rader, Mark; Alexeff, Igor

    1996-11-01

    A microwave plasma closing switch has been constructed using a fluorescent lamp as the central conductor of a coaxial line. When the lamp is energized, the coaxial line transmits microwaves. When the lamp is de-energized, the plasma conductor disappears, and the system reverts to a waveguide beyond cutoff. We have observed up to 61 dB difference in transmission between energized and de-energized operation. A simple model of the line using capacitors, inductors and resistors using the resistance measured in the tube predicts the observed behavior very successfully.

  3. Microwave noise modeling of FinFETs

    Science.gov (United States)

    Crupi, Giovanni; Caddemi, Alina; Schreurs, Dominique M. M.-P.; Wiatr, Wojciech; Mercha, Abdelkarim

    2011-02-01

    The noise characteristics of advanced silicon semiconductor devices fabricated with FinFET technology are investigated and modeled at the probe tip reference planes in the microwave frequency range. The transistor noise model is obtained by assigning an equivalent temperature to each resistor of the small signal equivalent circuit. These temperatures are selected to be equal to the room temperature with the exception of the temperature values of the intrinsic output, feedback, and substrate resistances, which are selected in order to reproduce accurately the 50 Ω noise factor measurements over a broadband frequency range going from 0.5 GHz up to 26.5 GHz. Accurate model simulations are obtained at such high frequencies, thanks to the inclusion of the noise temperature associated to the feedback and substrate resistances representing non-quasi-static effects which cannot be neglected in the investigated frequency range.

  4. 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.

  5. High Temperature Microwave Dielectric Properties of JSC-1AC Lunar Simulant

    Science.gov (United States)

    Allan, Shawn M.; Merritt, Brandon J.; Griffin, Brittany F.; Hintze, Paul E.; Shulman, Holly S.

    2011-01-01

    Microwave heating has many potential lunar applications including sintering regolith for lunar surface stabilization and heating regolith for various oxygen production reactors. The microwave properties of lunar simulants must be understood so this technology can be applied to lunar operations. Dielectric properties at microwave frequencies for a common lunar simulant, JSC-1AC, were measured up to 1100 C, which is approximately the melting point. The experimentally determined dielectric properties included real and imaginary permittivity (epsilon', epsilon"), loss tangent (tan delta), and half-power depth, the di stance at which a material absorbs 50% of incident microwave energy. Measurements at 2.45 GHz revealed tan delta of JSC-1A increases from 0.02 at 25 C to 0.31 at 110 C. The corresponding half-power depth decreases from a peak of 286 mm at 110 C, to 13 mm at 1100 C. These data indicate that JSC-1AC becomes more absorbing, and thus a better microwave heater as temperature increases. A half-power depth maximum at 100-200 C presents a barrier to direct microwave heating at low temperatures. Microwave heating experiments confirm the sluggish heating effect of weak absorption below 200 C, and increasingly strong absorption above 200 C, leading to rapid heating and melting of JSC-1AC.

  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. Microwave vegetation indices derived from satellite microwave radiometers

    Science.gov (United States)

    Vegetation indices are valuable in many fields of geosciences. Conventional, visible-near infrared, indices are often limited by the effects of atmosphere, background soil conditions, and saturation at high levels of vegetation. In this study, the theoretical basis for a new type of passive microwav...

  8. New Small Satellite Capabilities for Microwave Atmospheric Remote Sensing: The Earth Observing Nanosatellite-Microwave (EON-MW)

    Science.gov (United States)

    Blackwell, W. J.

    2015-12-01

    Four nanosatellite advanced technology missions flying microwave radiometers for high-resolution atmospheric sensing are in varying stages of development. Microwave instrumentation is particularly well suited for implementation on a very small satellite, as the sensor requirements for power, pointing, and spatial resolution (aperture size) can be accommodated by a nanosatellite platform. The first mission, the Microsized Microwave Atmospheric Satellite (MicroMAS), was developed to demonstrate temperature sounding in nine channels near 118 GHz on a 3U CubeSat (10x10x34 cm; 4.25 kg). MicroMAS was recently released from the International Space Station (ISS) for a 100-day mission, and while an eventual transmitter failure prevented demonstration of the radiometer payload, all key spacecraft subsystems provided on-orbit data to validate performance. Two 3U CubeSat follow-on missions, MicroMAS-2 (12 channels near 90, 118, 183, and 206 GHz; cross-track scanning) and MiRaTA (12 channels near 60, 183, and 206 GHz; no scanning; GPSRO onboard), will launch in 2016 for further demonstration. Building upon this work, the Earth Observing Nanosatellite-Microwave mission is being formulated by MIT Lincoln Laboratory for the NOAA National Environmental Satellite, Data, and Information Service as part of the Polar Follow-On (PFO) budget request to extend JPSS for two more missions, and provides a means to mitigate the risk of a gap in continuity of weather observations. The PFO request aims to achieve robustness in the polar satellite system to ensure continuity of NOAA's polar weather observations. The baseline EON-MW design accommodates a scanning 22-channel high-resolution microwave spectrometer on a 12U (22x22x34 cm, 20 kg) CubeSat platform to provide data continuity with the existing AMSU and ATMS microwave sounding systems. EON-MW will nominally be launched into a sun-synchronous orbit for a two to three year mitigation mission in 2019 that will also extend technology

  9. Land Surface Temperature and Emissivity Separation from Cross-Track Infrared Sounder Data with Atmospheric Reanalysis Data and ISSTES Algorithm

    Directory of Open Access Journals (Sweden)

    Yu-Ze Zhang

    2017-01-01

    Full Text Available The Cross-track Infrared Sounder (CrIS is one of the most advanced hyperspectral instruments and has been used for various atmospheric applications such as atmospheric retrievals and weather forecast modeling. However, because of the specific design purpose of CrIS, little attention has been paid to retrieving land surface parameters from CrIS data. To take full advantage of the rich spectral information in CrIS data to improve the land surface retrievals, particularly the acquisition of a continuous Land Surface Emissivity (LSE spectrum, this paper attempts to simultaneously retrieve a continuous LSE spectrum and the Land Surface Temperature (LST from CrIS data with the atmospheric reanalysis data and the Iterative Spectrally Smooth Temperature and Emissivity Separation (ISSTES algorithm. The results show that the accuracy of the retrieved LSEs and LST is comparable with the current land products. The overall differences of the LST and LSE retrievals are approximately 1.3 K and 1.48%, respectively. However, the LSEs in our study can be provided as a continuum spectrum instead of the single-channel values in traditional products. The retrieved LST and LSEs now can be better used to further analyze the surface properties or improve the retrieval of atmospheric parameters.

  10. Characteristics of observed tropopause height derived from L-band sounder over the Tibetan Plateau and surrounding areas

    Science.gov (United States)

    Jiang, Xiaoling; Wang, Donghai; Xu, Jianjun; Zhang, Yuwei; Chiu, Long S.

    2017-02-01

    The tropopause, which plays important roles in the stratosphere-troposphere exchange, is an interface between the troposphere and stratosphere. In this study, the characteristics of tropopause is investigated with the high vertical resolution daily sounding data during the period from 2008 to 2014 collected by the network of L-band sounder at 119 observational stations over Mainland China developed by the China Meteorological Administration (CMA). The results show that the tropopause height increases from the north to the south and has little correspondence with the station elevation. In addition, the spectral analyses and wavelet analyses are also performed to understand the intraseasonal variations of the tropopause. The results show that usually there are seasonal cycles with maximum in summer and minimum in winter. The strongest spectral band with period of 25-35 days is observed over the Southeast China. Besides, 20-60 days signals over the Changjiang River basin and the Tibetan Plateau has a good correlation to the Oceanic Niño Index (ONI), suggesting that the behavior of tropopause over the regions between 30oN and 40oN could relate to the Niño events.

  11. Mechanical design and qualification of IR filter mounts and filter wheel of INSAT-3D sounder for low temperature

    Science.gov (United States)

    Vora, A. P.; Rami, J. B.; Hait, A. K.; Dewan, C. P.; Subrahmanyam, D.; Kirankumar, A. S.

    2017-11-01

    Next generation Indian Meteorological Satellite will carry Sounder instrument having subsystem of filter wheel measuring Ø260mm and carrying 18 filters arranged in three concentric rings. These filters made from Germanium, are used to separate spectral channels in IR band. Filter wheel is required to be cooled to 214K and rotated at 600 rpm. This Paper discusses the challenges faced in mechanical design of the filter wheel, mainly filter mount design to protect brittle germanium filters from failure under stresses due to very low temperature, compactness of the wheel and casings for improved thermal efficiency, survival under vibration loads and material selection to keep it lighter in weight. Properties of Titanium, Kovar, Invar and Aluminium materials are considered for design. The mount has been designed to accommodate both thermal and dynamic loadings without introducing significant aberrations into the optics or incurring permanent alignment shifts. Detailed finite element analysis of mounts was carried out for stress verification. Results of the qualification tests are discussed for given temperature range of 100K and vibration loads of 12g in Sine and 11.8grms in Random at mount level. Results of the filter wheel qualification as mounted in Electro Optics Module (EOM) are also presented.

  12. Assimilation of clear sky Atmospheric Infrared Sounder radiances in short-term regional forecasts using community models

    Science.gov (United States)

    Lim, Agnes H. N.; Jung, James A.; Huang, Hung-Lung Allen; Ackerman, Steven A.; Otkin, Jason A.

    2014-01-01

    Regional assimilation experiments of clear-sky Atmospheric Infrared Sounder (AIRS) radiances were performed using the gridpoint statistical interpolation three-dimensional variational assimilation system coupled to the weather research and forecasting model. The data assimilation system and forecast model used in this study are separate community models; it cannot be assumed that the coupled systems work optimally. Tuning was performed on the data assimilation system and forecast model. Components tuned included the background error covariance matrix, the satellite radiance bias correction, the quality control procedures for AIRS radiances, the forecast model resolution, and the infrared channel selection. Assimilation metrics and diagnostics from the assimilation system were used to identify problems when combining separate systems. Forecasts initiated from analyses after assimilation were verified with model analyses, rawinsondes, nonassimilated satellite radiances, and 24 h-accumulated precipitation. Assimilation of clear sky AIRS radiances showed the largest improvement in temperature and radiance brightness temperature bias when compared with rawinsondes and satellite observations, respectively. Precipitation skill scores displayed minor changes with AIRS radiance assimilation. The 00 and 12 coordinated universal time (UTC) forecasts were typically of better quality than the 06 and 18 UTC forecasts, possibly due to the amount of AIRS data available for each assimilation cycle.

  13. Detection of Earth-rotation Doppler shift from Suomi National Polar-Orbiting Partnership Cross-Track Infrared Sounder.

    Science.gov (United States)

    Chen, Yong; Han, Yong; Weng, Fuzhong

    2013-09-01

    The Cross-Track Infrared Sounder (CrIS) on the Suomi National Polar-Orbiting Partnership Satellite is a Fourier transform spectrometer and provides a total of 1305 channels for sounding the atmosphere. Quantifying the CrIS spectral accuracy, which is directly related to radiometric accuracy, is crucial for improving its data assimilation in numerical weather prediction. In this study, a cross-correlation method is used for detecting the effect of Earth-rotation Doppler shift (ERDS) on CrIS observations. Based on a theoretical calculation, the ERDS can be as large as about 1.3 parts in 10(6) (ppm) near Earth's equator and at the satellite scan edge for a field of regard (FOR) of 1 or 30. The CrIS observations exhibit a relative Doppler shift as large as 2.6 ppm for a FOR pair of 1 and 30 near the equator. The variation of the ERDS with latitude and scan position detected from CrIS observations is similar to that derived theoretically, which indicates that the spectral stability of the CrIS instrument is very high. To accurately calibrate CrIS spectral accuracy, the ERDS effect should be removed. Since the ERDS is easily predictable, the Doppler shift is correctable in the CrIS spectra.

  14. Fusion of satellite-based imager and sounder data to construct supplementary high spatial resolution narrowband IR radiances

    Science.gov (United States)

    Weisz, Elisabeth; Baum, Bryan A.; Menzel, W. Paul

    2017-07-01

    Polar-orbiting weather satellite platforms generally include an imager and a sounder. With a data fusion method that uses these sensors, we demonstrate the ability to construct infrared (IR) absorption narrowband radiances at imager resolution. While a sensor such as MODIS has multiple IR absorption bands, the current visible infrared imaging radiometer suite (VIIRS) imager has only IR window bands. We show fusion results for IR radiances at 4.52 μm (CO2), 6.72 μm (H2O), and 13.94 μm (CO2) by comparing MODIS observed and constructed radiances for these bands. Both regional and global results are analyzed, with radiance differences tending to be fairly low and unbiased. Similar bands are constructed from VIIRS and CrIS data, with regional and global results shown. With this approach, it will be possible to improve continuity in derived cloud products over the generations of polar-orbiting weather satellite sensors and continue applications that require IR absorption bands.

  15. Fast and Accurate Collocation of the Visible Infrared Imaging Radiometer Suite Measurements with Cross-Track Infrared Sounder

    Directory of Open Access Journals (Sweden)

    Likun Wang

    2016-01-01

    Full Text Available Given the fact that Cross-track Infrared Sounder (CrIS and the Visible Infrared Imaging Radiometer Suite (VIIRS are currently onboard the Suomi National Polar-orbiting Partnership (Suomi NPP satellite and will continue to be carried on the same platform as future Joint Polar Satellite System (JPSS satellites for the next decade, it is desirable to develop a fast and accurate collocation scheme to collocate VIIRS products and measurements with CrIS for applications that rely on combining measurements from two sensors such as inter-calibration, geolocation assessment, and cloud detection. In this study, an accurate and fast collocation method to collocate VIIRS measurements within CrIS instantaneous field of view (IFOV directly based on line-of-sight (LOS pointing vectors is developed and discussed in detail. We demonstrate that this method is not only accurate and precise from a mathematical perspective, but also easy to implement computationally. More importantly, with optimization, this method is very fast and efficient and thus can meet operational requirements. Finally, this collocation method can be extended to a wide variety of sensors on different satellite platforms.

  16. Controlled zone microwave plasma system

    Science.gov (United States)

    Ripley, Edward B [Knoxville, TN; Seals, Roland D [Oak Ridge, TN; Morrell, Jonathan S [Knoxville, TN

    2009-10-20

    An apparatus and method for initiating a process gas plasma. A conductive plate having a plurality of conductive fingers is positioned in a microwave applicator. An arc forms between the conductive fingers to initiate the formation of a plasma. A transport mechanism may convey process materials through the plasma. A spray port may be provided to expel processed materials.

  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. 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

  19. Microwave applicators for BPH thermotherapy

    Science.gov (United States)

    Vrba, Jan; Hlavac, R.; Herza, Jan; Chovanec, Roman; Cvek, Jakub; Oppl, L.

    2004-04-01

    Paper deals with new results in the field of intracavitary microwave applicators used for Benign Prostatic Hyperplasia (BPH) treatment. We demonstrate here that it is necessary to use more sophisticated applicators than a simple monopole radiating structure. One of the good possibilities for safe and efficient treatments we propose here is a helix structure.

  20. 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 bias...

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. Impact of Missing Passive Microwave Sensors on Multi-Satellite Precipitation Retrieval Algorithm

    Directory of Open Access Journals (Sweden)

    Bin Yong

    2015-01-01

    Full Text Available The impact of one or two missing passive microwave (PMW input sensors on the end product of multi-satellite precipitation products is an interesting but obscure issue for both algorithm developers and data users. On 28 January 2013, the Version-7 TRMM Multi-satellite Precipitation Analysis (TMPA products were reproduced and re-released by National Aeronautics and Space Administration (NASA Goddard Space Flight Center because the Advanced Microwave Sounding Unit-B (AMSU-B and the Special Sensor Microwave Imager-Sounder-F16 (SSMIS-F16 input data were unintentionally disregarded in the prior retrieval. Thus, this study investigates the sensitivity of TMPA algorithm results to missing PMW sensors by intercomparing the “early” and “late” Version-7 TMPA real-time (TMPA-RT precipitation estimates (i.e., without and with AMSU-B, SSMIS-F16 sensors with an independent high-density gauge network of 200 tipping-bucket rain gauges over the Chinese Jinghe river basin (45,421 km2. The retrieval counts and retrieval frequency of various PMW and Infrared (IR sensors incorporated into the TMPA system were also analyzed to identify and diagnose the impacts of sensor availability on the TMPA-RT retrieval accuracy. Results show that the incorporation of AMSU-B and SSMIS-F16 has substantially reduced systematic errors. The improvement exhibits rather strong seasonal and topographic dependencies. Our analyses suggest that one or two single PMW sensors might play a key role in affecting the end product of current combined microwave-infrared precipitation estimates. This finding supports algorithm developers’ current endeavor in spatiotemporally incorporating as many PMW sensors as possible in the multi-satellite precipitation retrieval system called Integrated Multi-satellitE Retrievals for Global Precipitation Measurement mission (IMERG. This study also recommends users of satellite precipitation products to switch to the newest Version-7 TMPA datasets and

  6. A Microwave Blade Tip Clearance Sensor for Propulsion Health Monitoring

    Science.gov (United States)

    Woike, Mark R.; Abdul-Aziz, Ali; Bencic, Timothy J.

    2010-01-01

    Microwave sensor technology is being investigated by the NASA Glenn Research Center as a means of making non-contact structural health measurements in the hot sections of gas turbine engines. This type of sensor technology is beneficial in that it is accurate, it has the ability to operate at extremely high temperatures, and is unaffected by contaminants that are present in turbine engines. It is specifically being targeted for use in the High Pressure Turbine (HPT) and High Pressure Compressor (HPC) sections to monitor the structural health of the rotating components. It is intended to use blade tip clearance to monitor blade growth and wear and blade tip timing to monitor blade vibration and deflection. The use of microwave sensors for this application is an emerging concept. Techniques on their use and calibration needed to be developed. As a means of better understanding the issues associated with the microwave sensors, a series of experiments have been conducted to evaluate their performance for aero engine applications. This paper presents the results of these experiments.

  7. Study of microwave components for an electron cyclotron resonance ...

    Indian Academy of Sciences (India)

    rious aspects of the microwave system including design, fabrication, characterization and performance studies of the microwave components. Keywords. Microwave system; microwave studio software; network analyser; electron cyclotron resonance ion source. 1. Introduction. Microwave systems at 2.45 GHz have been ...

  8. Microwave Propagation Through Cultural Vegetation Canopies

    Science.gov (United States)

    Tavakoli, Ahad

    The need to understand the interaction of microwaves with vegetation canopies has markedly increased in recent years. This is due to advances made in remote sensing science, microwave technology, and signal processing circuits. One class of the earth's vegetation cover is man-made canopies, such as agricultural fields, orchards, and artificial forests. Contrary to natural vegetation terrain, location, spacing, and density of plants in a man-made vegetation canopy are deterministic quantities. As a result, the semi-deterministic nature of cultural vegetation canopies violate the random assumption of the radiative transfer theory and leads to experimented results that are in variance with model calculations. Hence, an alternative approach is needed to model the interaction of microwaves with such canopies. This thesis examines the propagation behavior through a canopy of corn plants. The corn canopy was selected as a representative of cultural vegetation canopies that are planted in parallel rows with an approximately fixed spacing between adjacent plants. Several experimental measurements were conducted to determine the transmission properties of a corn canopy in the 1-10 GHz range. The measurements which included horizontal propagation through the canopy as well as propagation at oblique incidence, were performed for defoliated canopies and for canopies with leaves. Through experimental observations and model development, the propagation behavior was found to be strongly dependent on the wavelength and the path length. At a wavelength in the neighborhood of 20 cm, for example, it was found that scattering by the stalks was coherent in nature for waves propagating horizontally through the canopy, which necessitated the development of a coherent-field model that uses Bragg scattering to account for the observed interference pattern in the transmitted beam. As the wavelength is made shorter, the semi-random spacing between plants becomes significant relative to the

  9. 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.

  10. The SPARC water vapor assessment II: intercomparison of satellite and ground-based microwave measurements

    Directory of Open Access Journals (Sweden)

    G. E. Nedoluha

    2017-12-01

    Full Text Available As part of the second SPARC (Stratosphere–troposphere Processes And their Role in Climate water vapor assessment (WAVAS-II, we present measurements taken from or coincident with seven sites from which ground-based microwave instruments measure water vapor in the middle atmosphere. Six of the ground-based instruments are part of the Network for the Detection of Atmospheric Composition Change (NDACC and provide datasets that can be used for drift and trend assessment. We compare measurements from these ground-based instruments with satellite datasets that have provided retrievals of water vapor in the lower mesosphere over extended periods since 1996. We first compare biases between the satellite and ground-based instruments from the upper stratosphere to the upper mesosphere. We then show a number of time series comparisons at 0.46 hPa, a level that is sensitive to changes in H2O and CH4 entering the stratosphere but, because almost all CH4 has been oxidized, is relatively insensitive to dynamical variations. Interannual variations and drifts are investigated with respect to both the Aura Microwave Limb Sounder (MLS; from 2004 onwards and each instrument's climatological mean. We find that the variation in the interannual difference in the mean H2O measured by any two instruments is typically  ∼  1%. Most of the datasets start in or after 2004 and show annual increases in H2O of 0–1 % yr−1. In particular, MLS shows a trend of between 0.5 % yr−1 and 0.7 % yr−1 at the comparison sites. However, the two longest measurement datasets used here, with measurements back to 1996, show much smaller trends of +0.1 % yr−1 (at Mauna Loa, Hawaii and −0.1 % yr−1 (at Lauder, New Zealand.

  11. Microwave drying of granules containing a moisture-sensitive drug: a promising alternative to fluid bed and hot air oven drying.

    Science.gov (United States)

    Chee, Sze Nam; Johansen, Anne Lene; Gu, Li; Karlsen, Jan; Heng, Paul Wan Sia

    2005-07-01

    The impact of microwave drying and binders (copolyvidone and povidone) on the degradation of acetylsalicylic acid (ASA) and physical properties of granules were compared with conventional drying methods. Moist granules containing ASA were prepared using a high shear granulator and dried with hot air oven, fluid bed or microwave (static or dynamic bed) dryers. Percent ASA degradation, size and size distribution, friability and flow properties of the granules were determined. Granules dried with the dynamic bed microwave dryer showed the least amount of ASA degradation, followed by fluid bed dryer, static bed microwave oven and hot air oven. The use of microwave drying with a static granular bed adversely affected ASA degradation and drying capability. Dynamic bed microwave dryer had the highest drying capability followed by fluid bed, static bed microwave dryer and conventional hot air oven. The intensity of microwave did not affect ASA degradation, size distribution, friability and flow properties of the granules. Mixing/agitating of granules during drying affected the granular physical properties studied. Copolyvidone resulted in lower amount of granular residual moisture content and ASA degradation on storage than povidone, especially for static bed microwave drying. In conclusion, microwave drying technology has been shown to be a promising alternative for drying granules containing a moisture-sensitive drug.

  12. CAMEX-3 ER-2 NAST-MTS V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The NPOESS Aircraft Sounder Testbed - Microwave Temperature Sounder (NAST-MTS) dataset contains information gathered during the Third Convection And Moisture...

  13. 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.

  14. The Level 2 research product algorithms for the Superconducting Submillimeter-Wave Limb-Emission Sounder (SMILES

    Directory of Open Access Journals (Sweden)

    P. Baron

    2011-10-01

    Full Text Available This paper describes the algorithms of the level-2 research (L2r processing chain developed for the Superconducting Submillimeter-Wave Limb-Emission Sounder (SMILES. The chain has been developed in parallel to the operational chain for conducting researches on calibration and retrieval algorithms. L2r chain products are available to the scientific community. The objective of version 2 is the retrieval of the vertical distribution of trace gases in the altitude range of 18–90 km. A theoretical error analysis is conducted to estimate the retrieval feasibility of key parameters of the processing: line-of-sight elevation tangent altitudes (or angles, temperature and ozone profiles. While pointing information is often retrieved from molecular oxygen lines, there is no oxygen line in the SMILES spectra, so the strong ozone line at 625.371 GHz has been chosen. The pointing parameters and the ozone profiles are retrieved from the line wings which are measured with high signal to noise ratio, whereas the temperature profile is retrieved from the optically thick line center. The main systematic component of the retrieval error was found to be the neglect of the non-linearity of the radiometric gain in the calibration procedure. This causes a temperature retrieval error of 5–10 K. Because of these large temperature errors, it is not possible to construct a reliable hydrostatic pressure profile. However, as a consequence of the retrieval of pointing parameters, pressure induced errors are significantly reduced if the retrieved trace gas profiles are represented on pressure levels instead of geometric altitude levels. Further, various setups of trace gas retrievals have been tested. The error analysis for the retrieved HOCl profile demonstrates that best results for inverting weak lines can be obtained by using narrow spectral windows.

  15. Neutral wind and density perturbations in the thermosphere created by gravity waves observed by the TIDDBIT sounder

    Science.gov (United States)

    Vadas, Sharon L.; Crowley, Geoff

    2017-06-01

    In this paper, we study the 10 traveling ionospheric disturbances (TIDs) observed at zobs˜283 km by the TIDDBIT ionospheric sounder on 30 October 2007 at 0400-0700 UT near Wallops Island, USA. These TIDs propagated northwest/northward and were previously found to be secondary gravity waves (GWs) from tropical storm Noel. An instrumented sounding rocket simultaneously measured a large neutral wind peak uH' with a similar azimuth at z ˜ 325 km. Using the measured TID amplitudes and wave vectors from the TIDDBIT system, together with ion-neutral theory, GW dissipative polarization relations and ray tracing, we determine the GW neutral horizontal wind and density perturbations as a function of altitude from 220 to 380 km. We find that there is a serious discrepancy between the GW dissipative theory and the observations unless the molecular viscosity, μ, decreases with altitude in the middle to upper thermosphere. Assuming that μ∝ρ¯q, where ρ¯ is the density, we find using GW dissipative theory that the GWs could have been observed at zobs and that one or more of the GWs could have caused the uH' wind peak at z≃325 km if q ˜ 0.67 for z≥220 km. This implies that the kinematic viscosity, ν=μ/ρ¯, increases less rapidly with altitude for z≥220 km: ν∝1/ρ¯0.33. This dependence makes sense because as ρ¯→0, the distance between molecules goes to infinity, which implies no molecular collisions and therefore no molecular viscosity μ.

  16. 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.

  17. 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 microwave radiation. Also histological changes were observed in the brain, liver, testis, kidney and spleen after whole-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.

  18. 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.

    2013-01-01

    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. PMID:23963358

  19. Compression of ultra-long microwave pulses using programmable microwave photonic phase filtering with > 100 complex-coefficient taps.

    Science.gov (United States)

    Song, Minhyup; Torres-Company, Victor; Wu, Rui; Metcalf, Andrew J; Weiner, Andrew M

    2014-03-24

    Microwave photonic filters with arbitrary phase response can be achieved by merging high-repetition-rate electro-optic frequency comb technology with line-by-line pulse shaping. When arranged in an interferometric configuration, the filter features a number of programmable complex-coefficient taps equal to the number of available comb lines. In this work, we use an ultrabroadband comb generator resulting in a microwave photonic phase filter with >100 complex-coefficient taps. We demonstrate the potential of this filter by performing programmable chirp control of ultrawideband waveforms that extend over long (>10 ns) temporal apertures. This work opens new possibilities for compensating realistic linear distortion impairments on ultrabroadband wireless signals spanning over dozens of nanosecond temporal apertures.

  20. Magnetic Resonance with Squeezed Microwaves

    Science.gov (United States)

    Bienfait, A.; Campagne-Ibarcq, P.; Kiilerich, A. H.; Zhou, X.; Probst, S.; Pla, J. J.; Schenkel, T.; Vion, D.; Esteve, D.; Morton, J. J. L.; Moelmer, K.; Bertet, P.

    2017-10-01

    Vacuum fluctuations of the electromagnetic field set a fundamental limit to the sensitivity of a variety of measurements, including magnetic resonance spectroscopy. We report the use of squeezed microwave fields, which are engineered quantum states of light for which fluctuations in one field quadrature are reduced below the vacuum level, to enhance the detection sensitivity of an ensemble of electronic spins at millikelvin temperatures. By shining a squeezed vacuum state on the input port of a microwave resonator containing the spins, we obtain a 1.2-dB noise reduction at the spectrometer output compared to the case of a vacuum input. This result constitutes a proof of principle of the application of quantum metrology to magnetic resonance spectroscopy.

  1. 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.

  2. Time-of-Flight Microwave Camera.

    Science.gov (United States)

    Charvat, Gregory; Temme, Andrew; Feigin, Micha; Raskar, Ramesh

    2015-10-05

    Microwaves can penetrate many obstructions that are opaque at visible wavelengths, however microwave imaging is challenging due to resolution limits associated with relatively small apertures and unrecoverable "stealth" regions due to the specularity of most objects at microwave frequencies. We demonstrate a multispectral time-of-flight microwave imaging system which overcomes these challenges with a large passive aperture to improve lateral resolution, multiple illumination points with a data fusion method to reduce stealth regions, and a frequency modulated continuous wave (FMCW) receiver to achieve depth resolution. The camera captures images with a resolution of 1.5 degrees, multispectral images across the X frequency band (8 GHz-12 GHz), and a time resolution of 200 ps (6 cm optical path in free space). Images are taken of objects in free space as well as behind drywall and plywood. This architecture allows "camera-like" behavior from a microwave imaging system and is practical for imaging everyday objects in the microwave spectrum.

  3. Microwave chemistry for inorganic nanomaterials synthesis.

    Science.gov (United States)

    Bilecka, Idalia; Niederberger, Markus

    2010-08-01

    This Feature Article gives an overview of microwave-assisted liquid phase routes to inorganic nanomaterials. Whereas microwave chemistry is a well-established technique in organic synthesis, its use in inorganic nanomaterials' synthesis is still at the beginning and far away from having reached its full potential. However, the rapidly growing number of publications in this field suggests that microwave chemistry will play an outstanding role in the broad field of Nanoscience and Nanotechnology. This article is not meant to give an exhaustive overview of all nanomaterials synthesized by the microwave technique, but to discuss the new opportunities that arise as a result of the unique features of microwave chemistry. Principles, advantages and limitations of microwave chemistry are introduced, its application in the synthesis of different classes of functional nanomaterials is discussed, and finally expected benefits for nanomaterials' synthesis are elaborated.

  4. Note: cryogenic coaxial microwave filters.

    Science.gov (United States)

    Tancredi, G; Schmidlin, S; Meeson, P J

    2014-02-01

    The careful filtering of microwave electromagnetic radiation is critical for controlling the electromagnetic environment for experiments in solid-state quantum information processing and quantum metrology at millikelvin temperatures. We describe the design and fabrication of a coaxial filter assembly and demonstrate that its performance is in excellent agreement with theoretical modelling. We further perform an indicative test of the operation of the filters by making current-voltage measurements of small, underdamped Josephson junctions at 15 mK.

  5. Compact planar microwave blocking filters

    Science.gov (United States)

    U-Yen, Kongpop (Inventor); Wollack, Edward J. (Inventor)

    2012-01-01

    A compact planar microwave blocking filter includes a dielectric substrate and a plurality of filter unit elements disposed on the substrate. The filter unit elements are interconnected in a symmetrical series cascade with filter unit elements being organized in the series based on physical size. In the filter, a first filter unit element of the plurality of filter unit elements includes a low impedance open-ended line configured to reduce the shunt capacitance of the filter.

  6. Comparing Cosmic Microwave Background Datasets

    OpenAIRE

    Knox, L.; Bond, J..R.; Jaffe, A. H.; Segal, M; Charbonneau, D

    1998-01-01

    To extract reliable cosmic parameters from cosmic microwave background datasets, it is essential to show that the data are not contaminated by residual non-cosmological signals. We describe general statistical approaches to this problem, with an emphasis on the case in which there are two datasets that can be checked for consistency. A first visual step is the Wiener filter mapping from one set of data onto the pixel basis of another. For more quantitative analyses we develop and apply both B...

  7. Directional microwave applicator and methods

    Science.gov (United States)

    Fink, Patrick W. (Inventor); Lin, Greg Y. (Inventor); Chu, Andrew W. (Inventor); Dobbins, Justin A. (Inventor); Arndt, G. Dickey (Inventor); Ngo, Phong H. (Inventor)

    2008-01-01

    A miniature microwave antenna is disclosed which may be utilized for biomedical applications such as, for example, radiation induced hyperthermia through catheter systems. One feature of the antenna is that it possesses azimuthal directionality despite its small size. This directionality permits targeting of certain tissues while limiting thermal exposure of adjacent tissue. One embodiment has an outer diameter of about 0.095'' (2.4 mm) but the design permits for smaller diameters.

  8. Laser Sounder Approach for Measuring Atmospheric CO2 Concentrations for the ASCENDS Mission

    Science.gov (United States)

    Abshire, J. B.; Riris, H.; Allan, G. R.; Sun, X.; Wilson, E.; Stephen, M. A.; Weaver, C.

    2008-12-01

    Accurate measurements of tropospheric CO2 abundances with global-coverage and monthly temporal resolution are needed to quantify processes that regulate CO2 exchange with the land and oceans. To meet this need, the 2007 Decadal Survey for Earth Science by the US National Research Council recommended a laser-based CO2 measuring mission called ASCENDS. In July 2008 NASA convened a science definition workshop for ASCENDS, which helped better define the mission and measurement requirements. We have been developing a technique for the remote measurement of tropospheric CO2 concentrations from aircraft and spacecraft. Our immediate goal is to develop and demonstrate the lidar technique and technology that will permit measurements of the CO2 column abundance over horizontal paths and from aircraft at the few-ppmv level. Our longer-term goal is to demonstrate the capabilities of the technique and instrument design needed for an ASCENDS-type mission. Our approach uses the 1570-nm band and a dual channel laser absorption spectrometer (ie DIAL used in altimeter mode). It uses several tunable fiber laser transmitters allowing simultaneous measurement of the absorption from a CO2 absorption line in the 1570 nm band, O2 extinction in the oxygen A-band, and surface height and aerosol backscatter in the same path. It directs the narrow co-aligned laser beams toward nadir, and measures the energy of the laser echoes reflected from land and water surfaces. The lasers are tuned on and off the sides of CO2 line and an O2 line (near 765 nm) at kHz rates. The receiver uses a telescope and photon counting detectors, and measures the background light and energies of the laser echoes from the surface along with scattering from any aerosols in the path. The gas extinction and column densities for the CO2 and O2 gases are estimated from the ratio of the on and off line signals via the DIAL technique. We use pulsed laser signals and time gating to isolate the laser echo signals from the

  9. Laser Sounder for Measuring Atmospheric CO2 Concentrations: Progress Toward Ascends

    Science.gov (United States)

    Abshire, J. B.; Kawa, S. R.; Riris, H.; Allan, G. R.; Sun, X.; Stephen, M. A.; Wilson, E.; Burris, J. F.; Mao, J.

    2008-01-01

    The next generation of space-based, active remote sensing instruments for measurement of tropospheric CO2 promises a capability to quantify global carbon sources and sinks at regional scales. Active (laser) methods will extend CO2 measurement coverage in time, space, and perhaps precision such that the underlying mechanisms for carbon exchange at the surface can be understood with .sufficient detail to confidently project the future of carbon-climate interaction and the influence of remediative policy actions. The recent Decadal Survey for Earth Science by the US National Research Council has recommended such a mission called the Active Sensing of CO2 Emissions over Nights, Days, and Seasons (ASCENDS) for launch in 2013-2016. We have been developing a laser technique for measurement of tropospheric CO2 for a number of years. Our immediate goal is to develop and demonstrate the method and instrument technology that will permit measurements of the CO2 column abundance over a horizontal path and from aircraft at the few-ppmv level. Our longer-term goal is to demonstrate the required capabilities of the technique, develop a space mission approach, and design the instrument for an ASCENDS-type mission. Our approach is to use a dual channel laser absorption spectrometer (i.e., differential absorption in altimeter mode), which continuously measures from a near-polar circular orbit. We use several co-aligned tunable fiber laser transmitters allowing simultaneous measurement of the absorption from a CO2 line in the 1570 nm band, O2 extinction in the oxygen A-band (near 765 nm), and aerosol backscatter in the same measurement path. We measure the energy of the laser echoes at nadir reflected from land and water surfaces, day and night. The lasers have spectral widths much narrower than the gas absorption lines and are turned on and off the selected CO2 and O2 lines at kHz rates. The gas extinction and column densities for the CO2 and O2 gases are estimated from the ratio of

  10. 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.

  11. Comparison of microwave-assisted and conventional hydrodistillation in the extraction of essential oils from mango (Mangifera indica L.) flowers.

    Science.gov (United States)

    Wang, Hong-Wu; Liu, Yan-Qing; Wei, Shou-Lian; Yan, Zi-Jun; Lu, Kuan

    2010-10-29

    Microwave-assisted hydrodistillation (MAHD) is an advanced hydrodistillation (HD) technique, in which a microwave oven is used in the extraction process. MAHD and HD methods have been compared and evaluated for their effectiveness in the isolation of essential oils from fresh mango (Mangifera indica L.) flowers. MAHD offers important advantages over HD in terms of energy savings and extraction time (75 min against 4 h). The composition of the extracted essential oils was investigated by GC-FID and GC-MS. Results indicate that the use of microwave irradiation did not adversely influence the composition of the essential oils. MAHD was also found to be a green technology.

  12. Microwave thawing of frozen parenteral solutions.

    Science.gov (United States)

    Walter, C W; Pauly, J A; Ausman, R K; Kundsin, R B; Holmes, C J

    1983-01-01

    A commercially available microwave oven modified for use at medication stations throughout hospitals allows timely thawing of frozen parenteral solutions. The inherent problems of safety and uniform heating have been overcome, thus making possible the preparation, storage, and distribution of admixtures on a regional basis and ensuring the integrity of the product. Most parenteral medications are not degraded by microwave energy, and thawing by microwave energy permits timely administration and allows coordination of medication for a series of patients.

  13. 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.

  14. SciDAC's Earth System Grid Center for Enabling Technologies Semiannual Progress Report October 1, 2010 through March 31, 2011

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Dean N. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2011-04-02

    Laboratory (ORNL), Pacific Marine Environmental Laboratory (PMEL)/NOAA, Rensselaer Polytechnic Institute (RPI), and University of Southern California, Information Sciences Institute (USC/ISI). All ESG-CET work is accomplished under DOE open-source guidelines and in close collaboration with the project's stakeholders, domain researchers, and scientists. Through the ESG project, the ESG-CET team has developed and delivered a production environment for climate data from multiple climate model sources (e.g., CMIP (IPCC), CESM, ocean model data (e.g., Parallel Ocean Program), observation data (e.g., Atmospheric Infrared Sounder, Microwave Limb Sounder), and analysis and visualization tools) that serves a worldwide climate research community. Data holdings are distributed across multiple sites including LANL, LBNL, LLNL, NCAR, and ORNL as well as unfunded partners sites such as the Australian National University (ANU) National Computational Infrastructure (NCI), the British Atmospheric Data Center (BADC), the Geophysical Fluid Dynamics Laboratory/NOAA, the Max Planck Institute for Meteorology (MPI-M), the German Climate Computing Centre (DKRZ), and NASA/JPL. As we transition from development activities to production and operations, the ESG-CET team is tasked with making data available to all users who want to understand it, process it, extract value from it, visualize it, and/or communicate it to others. This ongoing effort is extremely large and complex, but it will be incredibly valuable for building 'science gateways' to critical climate resources (such as CESM, CMIP5, ARM, NARCCAP, Atmospheric Infrared Sounder (AIRS), etc.) for processing the next IPCC assessment report. Continued ESG progress will result in a production-scale system that will empower scientists to attempt new and exciting data exchanges, which could ultimately lead to breakthrough climate science discoveries.

  15. Microwave annealing of indium tin oxide nanoparticle ink patterned by ink-jet printing.

    Science.gov (United States)

    Kim, Jong-Woong; Choi, Jang-Woo; Hong, Sung-Jei; Kwak, Min-Gi

    2013-09-01

    Indium tin oxide (ITO) is one of the most widely used transparent conducting oxides because of its two chief properties, electrical conductivity and optical transparency, as well as the ease with which it can be deposited as a thin film. In this study, we fabricated the ITO nanoparticles, and dispersed them in an organic mixture of liquid to make a solution for printing. The solution was ink-jet printed on a glass, and we employed microwave heating technology to make the ITO coated layer conductive and transparent. Microwave technology uses electromagnetic waves that pass through material and cause its molecules to oscillate, generating heat. It generates heat within the material and heats the entire volume at about the same rate. The ITO layers could be successfully annealed by the microwave irradiation, which is resulted in the sheet resistance of 365 ohm/sq and the transmittance of 84% within only 15 min of heating.

  16. A Microwave-Based Chemical Factory in the Lab: From Milligram to Multigram Preparations

    Directory of Open Access Journals (Sweden)

    Laura Rinaldi

    2015-01-01

    Full Text Available Microwave technology is changing the way we design and optimize synthetic protocols and their scaling up to multigram production levels. The latest generation of dedicated microwave reactors enables operators to quickly screen reaction conditions by means of parallel tests and select the best catalyst, solvent, and conditions. Pilot scale synthetic procedures require flow-through conditions in microwave flow reactors which can be obtained by adapting classic batch protocols. Microwave-assisted chemical processes play a pivotal role in the design of sustainable multigram preparations which address the double requirement of process intensification and competitive production costs. Although most researchers are likely to be acquainted with the great potential of dielectric heating, the advantages and disadvantages of a particular device or the conditions needed to maximize efficiency and functionality are often overlooked. The double aims of the present review are to provide a panoramic snapshot of commercially available lab microwave reactors and their features as well as highlighting a few selected applications of microwave chemistry of particular relevance.

  17. TCSP ER-2 MICROWAVE TEMPERATURE PROFILER (MTP) V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The TCSP ER-2 Microwave Temperature Profiler (MTP) dataset was collected by the ER-2 Microwave Temperature Profiler (MTP), which is a passive microwave radiometer...

  18. Use of microwave in diagnostic pathology

    Directory of Open Access Journals (Sweden)

    Basavaradhya Sahukar Shruthi

    2013-01-01

    Microwaves a form of electromagnetic wave-induced heat, when applied in histotechnology, reproducibly yields histolologic material of similar or superior quality to that provided by conventional processing methods, making it more popular in the recent years. A laboratory microwave offers features like maximum output of 2000-3000 watts, an in-built source of adjustable temperature probe, facility for ventilation of hazardous fumes, but is expensive. Considering the usefulness of microwave in histotechnology, i.e., reducing the time required for the diagnosis, replacing the conventional equipments of laboratories by microwave-guided ones is a remarkable and an acceptable change.

  19. Time-of-Flight Microwave Camera

    National Research Council Canada - National Science Library

    Charvat, Gregory; Temme, Andrew; Feigin, Micha; Raskar, Ramesh

    2015-01-01

    .... We demonstrate a multispectral time-of-flight microwave imaging system which overcomes these challenges with a large passive aperture to improve lateral resolution, multiple illumination points...

  20. Joint NOSC/NRL (Naval Ocean Systems Center/Naval Research Laboratory) InP Microwave/Millimeter Wave Technology Workshop Held in San Diego, California on 25-26 January 1989

    Science.gov (United States)

    1989-12-01

    Oklahoma, Norman, OK. 1230 Lunch 3 ATTENDANCE LIST Dr. Leye Aina Mr. Brad Boos (Code 6852) Allied-Signal Aerospace Technology Naval Research...Insulated-Gate FETs Eric A. Martin,’ Leye A. Aina, Agis A. Iliadis,t Mike R. Mattingly, Erica Hempfling Allied-Signal Aerospace Company, Aerospace...52Al0.4sAs heterostructure has high band offset and better carrier confinement Applications * High Speed Devices .MO FET-7 ( tic 7tu m re. * Detectors

  1. Laser Sounder for Global Measurement of CO2 Concentrations in the Troposphere from Space

    Science.gov (United States)

    Abshire, James B.; Riris, Haris; Kawa, S. Randy; Sun, Xiaoli; Chen, Jeffrey; Stephen, Mark A.; Collatz, G. James; Mao, Jianping; Allan, Graham

    2007-01-01

    Measurements of tropospheric CO2 abundance with global-coverage, a few hundred km spatial and monthly temporal resolution are needed to quantify processes that regulate CO2 storage by the land and oceans. The Orbiting Carbon Observatory (OCO) is the first space mission focused on atmospheric CO2 for measuring total column CO, and O2 by detecting the spectral absorption in reflected sunlight. The OCO mission is an essential step, and will yield important new information about atmospheric CO2 distributions. However there are unavoidable limitations imposed by its measurement approach. These include best accuracy only during daytime at moderate to high sun angles, interference by cloud and aerosol scattering, and limited signal from CO2 variability in the lower tropospheric CO2 column. We have been developing a new laser-based technique for the remote measurement of the tropospheric CO2 concentrations from orbit. Our initial goal is to demonstrate a lidar technique and instrument technology that will permit measurements of the CO2 column abundance in the lower troposphere from aircraft. Our final goal is to develop a space instrument and mission approach for active measurements of the CO2 mixing ratio at the 1-2 ppmv level. Our technique is much less sensitive to cloud and atmospheric scattering conditions and would allow continuous measurements of CO2 mixing ratio in the lower troposphere from orbit over land and ocean surfaces during day and night. Our approach is to use the 1570nm CO2 band and a 3-channel laser absorption spectrometer (i.e. lidar used an altimeter mode), which continuously measures at nadir from a near polar circular orbit. The approach directs the narrow co-aligned laser beams from the instrument's lasers toward nadir, and measures the energy of the laser echoes reflected from land and water surfaces. It uses several tunable fiber laser transmitters which allowing measurement of the extinction from a single selected CO2 absorption line in the 1570

  2. Effects of LiF on microwave dielectric properties of 0.25Ca0.8Sr0 ...

    Indian Academy of Sciences (India)

    Administrator

    Indian Academy of Sciences. 1223 ... 3Department of Information Engineering, Guilin University of Aerospace Technology, Guilin 541004, PR China ... Keywords. 0.25Ca0.8Sr0.2TiO3–0.75Li0.5Nd0.5TiO3; microwave dielectric properties; microstructures; LiF. 1. Introduction. Microwave dielectric materials with predictable ...

  3. 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...

  4. Structural Health Monitoring on Turbine Engines Using Microwave Blade Tip Clearance Sensors

    Science.gov (United States)

    Woike, Mark; Abdul-Aziz, Ali; Clem, Michelle

    2014-01-01

    The ability to monitor the structural health of the rotating components, especially in the hot sections of turbine engines, is of major interest to aero community in improving engine safety and reliability. The use of instrumentation for these applications remains very challenging. It requires sensors and techniques that are highly accurate, are able to operate in a high temperature environment, and can detect minute changes and hidden flaws before catastrophic events occur. The National Aeronautics and Space Administration (NASA) has taken a lead role in the investigation of new sensor technologies and techniques for the in situ structural health monitoring of gas turbine engines. As part of this effort, microwave sensor technology has been investigated as a means of making high temperature non-contact blade tip clearance, blade tip timing, and blade vibration measurements for use in gas turbine engines. This paper presents a summary of key results and findings obtained from the evaluation of two different types of microwave sensors that have been investigated for use possible in structural health monitoring applications. The first is a microwave blade tip clearance sensor that has been evaluated on a large scale Axial Vane Fan, a subscale Turbofan, and more recently on sub-scale turbine engine like disks. The second is a novel microwave based blade vibration sensor that was also used in parallel with the microwave blade tip clearance sensors on the experiments with the sub-scale turbine engine disks.

  5. Behaviors of young children around microwave ovens.

    Science.gov (United States)

    Robinson, Marla R; O'Connor, Annemarie; Wallace, Lindsay; Connell, Kristen; Tucker, Katherine; Strickland, Joseph; Taylor, Jennifer; Quinlan, Kyran P; Gottlieb, Lawrence J

    2011-11-01

    Scald burn injuries are the leading cause of burn-related emergency room visits and hospitalizations for young children. A portion of these injuries occur when children are removing items from microwave ovens. This study assessed the ability of typically developing children aged 15 months to 5 years to operate, open, and remove the contents from a microwave oven. The Denver Developmental Screening Test II was administered to confirm typical development of the 40 subjects recruited. All children recruited and enrolled in this study showed no developmental delays in any domain in the Denver Developmental Screening Test II. Children were observed for the ability to open both a push and pull microwave oven door, to start the microwave oven, and to remove a cup from the microwave oven. All children aged 4 years were able to open the microwaves, turn on the microwave, and remove the contents. Of the children aged 3 years, 87.5% were able to perform all study tasks. For children aged 2 years, 90% were able to open both microwaves, turn on the microwave, and remove the contents. In this study, children as young as 17 months could start a microwave oven, open the door, and remove the contents putting them at significant risk for scald burn injury. Prevention efforts to improve supervision and caregiver education have not lead to a significant reduction in scald injuries in young children. A redesign of microwave ovens might prevent young children from being able to open them thereby reducing risk of scald injury by this mechanism.

  6. 75 FR 42611 - Energy Conservation Program for Consumer Products: Test Procedure for Microwave Ovens

    Science.gov (United States)

    2010-07-22

    ..., Energy Efficiency and Renewable Energy, Building Technologies Program, EE-2J, 1000 Independence Avenue... Procedure for Microwave Ovens AGENCY: Office of Energy Efficiency and Renewable Energy, Department of Energy... of Energy, Forrestal Building, Room 8E-089, 1000 Independence Avenue, SW., Washington, DC 20585-0121...

  7. 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

  8. Feasibility, engineering aspects and physics reach of microwave cavity experiments searching for hidden photons and axions

    CERN Document Server

    Caspers, Friedhelm; Ringwald, A

    2009-01-01

    Using microwave cavities one can build a resonant “light-shining-through-walls” experiment to search for hidden sector photons and axion like particles, predicted in many extensions of the standard model. In this note we make a feasibility study of the sensitivities which can be reached using state of the art technology.

  9. Feasibility, engineering aspects and physics reach of microwave cavity experiments searching for hidden photons and axions

    Energy Technology Data Exchange (ETDEWEB)

    Caspers, F. [CERN, Geneva (Switzerland); Jaeckel, J. [Univ. of Durham, Inst. for Particle Physics and Phenomenology (United Kingdom); Ringwald, A. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2009-08-15

    Using microwave cavities one can build a resonant ''light-shining-through-walls'' experiment to search for hidden sector photons and axion like particles, predicted in many extensions of the standard model. In this note we make a feasibility study of the sensitivities which can be reached using state of the art technology. (orig.)

  10. Photon noise limited radiation detection with lens-antenna coupled microwave kinetic inductance detectors

    NARCIS (Netherlands)

    Yates, S. J. C.; Baselmans, J. J. A.; Endo, A.; Janssen, R. M. J.; Ferrari, L.; Diener, P.; Barychev, Andrei

    2011-01-01

    Microwave kinetic inductance detectors (MKIDs) have shown great potential for sub-mm instrumentation because of the high scalability of the technology. Here, we demonstrate for the first time in the sub-mm band (0.1-2 mm) a photon noise limited performance of a small antenna coupled MKID detector

  11. Photon noise limited radiation detection with lens-antenna coupled microwave kinetic inductance detectors

    NARCIS (Netherlands)

    Yates, S.J.C.; Baselmans, J.J.A.; Endo, A.; Janssen, R.M.J.; Ferrari, L.; Diener, P.; Baryshev, A.M.

    2011-01-01

    Microwave kinetic inductance detectors (MKIDs) have shown great potential for sub-mm instrumentation because of the high scalability of the technology. Here, we demonstrate for the first time in the sub-mm band (0.1–2 mm) a photon noise limited performance of a small antenna coupled MKID detector

  12. 76 FR 12825 - Energy Conservation Program for Consumer Products: Test Procedure for Microwave Ovens

    Science.gov (United States)

    2011-03-09

    .... Department of Energy, Building Technologies Program, 6th Floor, 950 L'Enfant Plaza, SW., Washington, DC 20024... with or without thermal elements designed for surface browning of food and combination ovens. DOE..., including microwave ovens with or without thermal elements designed for surface browning of food. DOE stated...

  13. Microwave assisted bi-functional activation of β-bromo-tert-alcohols

    Indian Academy of Sciences (India)

    Spice and Flavour Science Department, CSIR-Central Food Technological Research Institute,. Mysore 570 020, India e-mail: bettadaiah@cftri.res.in ... ists to adopt microwave-assisted synthesis in this field. β-Bromo-tert-alcohols are the products of functional- ization of olefins by a process called co-halogenation.5. They are ...

  14. Magnetic and microwave-absorbing properties of SrAl4Fe8O19 ...

    Indian Academy of Sciences (India)

    Key Laboratory of Auxiliary Chemistry & Technology for Chemical Industry, Ministry of Education,. Shaanxi University of ... technique also significantly affected the magnetic properties and microwave-absorptivity. Conversely, calcining tem- ... The grain size was found to be a key factor affecting the property of the powder.

  15. 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.

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

    Indian Academy of Sciences (India)

    Keywords. Nanomaterials; nanospheres; CVD; electric; magnetic; microwave absorption properties. 1. Introduction. In recent years, microwave absorbing materials have attracted considerable attention because it is an essential part of a stealthy defense system for all military platforms, either as aircraft, sea or land vehicles.

  17. Microwave synthesis and mechanical characterization of functionally ...

    Indian Academy of Sciences (India)

    Microwave synthesis and mechanical characterization of functionally graded material for applications in fusion devices ... compact with fine microstructure and good mechanical property has been synthesized by employing microwave heating method at a temperature of 800 °C and in a short processing time of 30 min.

  18. Microwave Accelerated Aza-Claisen Rearrangement

    Directory of Open Access Journals (Sweden)

    Eva Gajdošíková

    2008-11-01

    Full Text Available A study of microwave-induced and standard thermal Overman rearrangement of selected allylic trichloroacetimidates 1a-1f, 6-8 to the corresponding acetamides 2a-2f, 9-11 is reported. The microwave-assisted rearrangement of trifluoroacetimidate 13 is also described. Using this methodology, an efficient access to versatile allylic trihaloacetamides building synthons was established.

  19. Characteristics of microwave propagation in vapourised troposphere ...

    African Journals Online (AJOL)

    Microwave communication equipment design in temperate region may not be very suitable in the tropics because the characteristics of the troposphere as the medium of propagation differ ... The meteorological vertical data taken from radiosonde confirms evidence of super-refraction and ducting of the microwave signal.

  20. 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 ... is energy conversion rather than heat transfer. Since micro- .... present review paper provides an overview of the micro- wave ...

  1. 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...

  2. 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...

  3. 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…

  4. Top Sounder Ice Penetration

    Science.gov (United States)

    Porter, D. L.; Goemmer, S. A.; Sweeney, J. H.

    2014-12-01

    Ice draft measurements are made as part of normal operations for all US Navy submarines operating in the Arctic Ocean. The submarine ice draft data are unique in providing high resolution measurements over long transects of the ice covered ocean. The data has been used to document a multidecadal drop in ice thickness, and for validating and improving numerical sea-ice models. A submarine upward-looking sonar draft measurement is made by a sonar transducer mounted in the sail or deck of the submarine. An acoustic beam is transmitted upward through the water column, reflecting off the bottom of the sea ice and returning to the transducer. Ice thickness is estimated as the difference between the ship's depth (measured by pressure) and the acoustic range to the bottom of the ice estimated from the travel time of the sonar pulse. Digital recording systems can provide the return off the water-ice interface as well as returns that have penetrated the ice. Typically, only the first return from the ice hull is analyzed. Information regarding ice flow interstitial layers provides ice age information and may possibly be derived with the entire return signal. The approach being investigated is similar to that used in measuring bottom sediment layers and will involve measuring the echo level from the first interface, solving the reflection loss from that transmission, and employing reflection loss versus impedance mismatch to ascertain ice structure information.

  5. Microwave remote sensing laboratory design

    Science.gov (United States)

    Friedman, E.

    1979-01-01

    Application of active and passive microwave remote sensing to the study of ocean pollution is discussed. Previous research efforts, both in the field and in the laboratory were surveyed to derive guidance for the design of a laboratory program of research. The essential issues include: choice of radar or radiometry as the observational technique; choice of laboratory or field as the research site; choice of operating frequency; tank sizes and material; techniques for wave generation and appropriate wavelength spectrum; methods for controlling and disposing of pollutants used in the research; and pollutants other than oil which could or should be studied.

  6. 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"

  7. Simulations of the Microwave Sky

    Energy Technology Data Exchange (ETDEWEB)

    Sehgal, Neelima; /KIPAC, Menlo Park; Bode, Paul; /Princeton U., Astrophys. Sci. Dept.; Das, Sudeep; /Princeton U., Astrophys. Sci. Dept. /Princeton U.; Hernandez-Monteagudo, Carlos; /Garching, Max Planck Inst.; Huffenberger, Kevin; /Miami U.; Lin, Yen-Ting; /Tokyo U., IPMU; Ostriker, Jeremiah P.; /Princeton U., Astrophys. Sci. Dept.; Trac, Hy; /Harvard-Smithsonian Ctr. Astrophys.

    2009-12-16

    We create realistic, full-sky, half-arcminute resolution simulations of the microwave sky matched to the most recent astrophysical observations. The primary purpose of these simulations is to test the data reduction pipeline for the Atacama Cosmology Telescope (ACT) experiment; however, we have widened the frequency coverage beyond the ACT bands and utilized the easily accessible HEALPix map format to make these simulations applicable to other current and near future microwave background experiments. Some of the novel features of these simulations are that the radio and infrared galaxy populations are correlated with the galaxy cluster and group populations, the primordial microwave background is lensed by the dark matter structure in the simulation via a ray-tracing code, the contribution to the thermal and kinetic Sunyaev-Zel'dovich (SZ) signals from galaxy clusters, groups, and the intergalactic medium has been included, and the gas prescription to model the SZ signals has been refined to match the most recent X-ray observations. The cosmology adopted in these simulations is also consistent with the WMAP 5-year parameter measurements. From these simulations we find a slope for the Y{sub 200} - M{sub 200} relation that is only slightly steeper than self-similar, with an intrinsic scatter in the relation of {approx} 14%. Regarding the contamination of cluster SZ flux by radio galaxies, we find for 148 GHz (90 GHz) only 3% (4%) of halos have their SZ decrements contaminated at a level of 20% or more. We find the contamination levels higher for infrared galaxies. However, at 90 GHz, less than 20% of clusters with M{sub 200} > 2.5 x 10{sup 14}M{sub {circle_dot}} and z < 1.2 have their SZ decrements filled in at a level of 20% or more. At 148 GHz, less than 20% of clusters with M{sub 200} > 2.5 x 10{sup 14}M{sub {circle_dot}} and z < 0.8 have their SZ decrements filled in at a level of 50% or larger. Our models also suggest that a population of very high flux

  8. 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

  9. Stochastic model in microwave propagation

    Energy Technology Data Exchange (ETDEWEB)

    Ranfagni, A. [“Nello Carrara” Institute of Applied Physics, CNR Florence Research Area, Via Madonna del Piano 10, 50019 Sesto Fiorentino (Italy); Mugnai, D., E-mail: d.mugnai@ifac.cnr.it [“Nello Carrara” Institute of Applied Physics, CNR Florence Research Area, Via Madonna del Piano 10, 50019 Sesto Fiorentino (Italy)

    2011-11-28

    Further experimental results of delay time in microwave propagation are reported in the presence of a lossy medium (wood). The measurements show that the presence of a lossy medium makes the propagation slightly superluminal. The results are interpreted on the basis of a stochastic (or path integral) model, showing how this model is able to describe each kind of physical system in which multi-path trajectories are present. -- Highlights: ► We present new experimental results on electromagnetic “anomalous” propagation. ► We apply a path integral theoretical model to wave propagation. ► Stochastic processes and multi-path trajectories in propagation are considered.

  10. Inter-Comparison of S-NPP VIIRS and Aqua MODIS Thermal Emissive Bands Using Hyperspectral Infrared Sounder Measurements as a Transfer Reference

    Directory of Open Access Journals (Sweden)

    Yonghong Li

    2016-01-01

    Full Text Available This paper compares the calibration consistency of the spectrally-matched thermal emissive bands (TEB between the Suomi National Polar-orbiting Partnership (S-NPP Visible Infrared Imaging Radiometer Suite (VIIRS and the Aqua Moderate Resolution Imaging Spectroradiometer (MODIS, using observations from their simultaneous nadir overpasses (SNO. Nearly-simultaneous hyperspectral measurements from the Aqua Atmospheric Infrared Sounder(AIRS and the S-NPP Cross-track Infrared Sounder (CrIS are used to account for existing spectral response differences between MODIS and VIIRS TEB. The comparison uses VIIRS Sensor Data Records (SDR in MODIS five-minute granule format provided by the NASA Land Product and Evaluation and Test Element (PEATE and Aqua MODIS Collection 6 Level 1 B (L1B products. Each AIRS footprint of 13.5 km (or CrIS field of view of 14 km is co-located with multiple MODIS (or VIIRS pixels. The corresponding AIRS- and CrIS-simulated MODIS and VIIRS radiances are derived by convolutions based on sensor-dependent relative spectral response (RSR functions. The VIIRS and MODIS TEB calibration consistency is evaluated and the two sensors agreed within 0.2 K in brightness temperature. Additional factors affecting the comparison such as geolocation and atmospheric water vapor content are also discussed in this paper.

  11. Miniature Microwave Bandpass Filter Based on EBG Structures

    DEFF Research Database (Denmark)

    Zhurbenko, Vitaliy; Krozer, Viktor; Meincke, Peter

    2006-01-01

    as compared to stepped-impedance hairpin (SIH) resonators with similar response. The new bandpass filter has a reduced footprint and can be fabricated in standard thick-film manufacturing technology. Measured and simulated results exhibit good agreement. The measured results show improvement in the filter......A new design of a planar microwave filter, based on rejection band properties of an electrically small electromagnetic bandgap (EBG) structure, is proposed. The proposed EBG structure demonstrates effective impedance manipulation, exhibits a simple analysis, and is about three times smaller...... characteristics in comparison to existing SIH filter design....

  12. Microwave chirality discrimination in enantiomeric liquids

    Science.gov (United States)

    Hollander, E.; Kamenetskii, E. O.; Shavit, R.

    2017-07-01

    Chirality discrimination is of fundamental interest in biology, chemistry, and metamaterial studies. In optics, near-field plasmon-resonance spectroscopy with superchiral probing fields is effectively applicable for analyses of large biomolecules with chiral properties. We show possibility for microwave near-field chirality discrimination analysis based on magnon-resonance spectroscopy. Newly developed capabilities in microwave sensing using magnetoelectric (ME) probing fields originated from multiresonance magnetic-dipolar-mode oscillations in quasi-2D yttrium-iron-garnet disks provide potential for unprecedented measurements of chemical and biological objects. We report on microwave near-field chirality discrimination for aqueous D- and L-glucose solutions. The shown ME-field sensing is addressed to deepen our understanding of microwave-biosystem interactions. It can also be important for an analysis and design of microwave chiral metamaterials.

  13. Applications of Graphene at Microwave Frequencies

    Directory of Open Access Journals (Sweden)

    M. Bozzi

    2015-09-01

    Full Text Available In view to the epochal scenarios that nanotechnology discloses, nano-electronics has the potential to introduce a paradigm shift in electronic systems design similar to that of the transition from vacuum tubes to semiconductor devices. Since low dimensional (1D and 2D nano-structured materials exhibit unprecedented electro-mechanical properties in a wide frequency range, including radio-frequencies (RF, microwave nano-electronics provides an enormous and yet widely undiscovered opportunity for the engineering community. Carbon nano-electronics is one of the main research routes of RF/microwave nano-electronics. In particular, graphene has shown proven results as an emblematic protagonist, and a real solution for a wide variety of microwave electronic devices and circuits. This paper introduces graphene properties in the microwave range, and presents a paradigm of novel graphene-based devices and applications in the microwave/RF frequency range.

  14. A Microwave Thruster for Spacecraft Propulsion

    Energy Technology Data Exchange (ETDEWEB)

    Chiravalle, Vincent P [Los Alamos National Laboratory

    2012-07-23

    This presentation describes how a microwave thruster can be used for spacecraft propulsion. A microwave thruster is part of a larger class of electric propulsion devices that have higher specific impulse and lower thrust than conventional chemical rocket engines. Examples of electric propulsion devices are given in this presentation and it is shown how these devices have been used to accomplish two recent space missions. The microwave thruster is then described and it is explained how the thrust and specific impulse of the thruster can be measured. Calculations of the gas temperature and plasma properties in the microwave thruster are discussed. In addition a potential mission for the microwave thruster involving the orbit raising of a space station is explored.

  15. Destruction and Dechlorination of Aroclor1254 in Real Waste Transformer Oil Using Microwave Irradiation, Microwave Absorbent and Reactive Materials

    Directory of Open Access Journals (Sweden)

    Bahram Kamarehie

    2014-09-01

    Full Text Available Background: In this research, the decomposition of Aroclor 1254, including 20 kinds of poly chlorinated biphenyls (PCBs, in real waste transformer oil in the presence of PEG1000, NaOH, zero valent iron and H2O by microwave (MW irradiation was studied. Methods: Central composites design (CCD method was carried out for experimental design. The effects of microwave power levels (200- 1000 W, reaction time (30-600 s, polyethylene glycol (PEG (1.5-7.5 g, zero valent iron powder (0.3-1.5 g, NaOH (0.3-1.5 g and H2O (0.4-2 ml were surveyed on the decomposition efficiency of PCBs. Results: The results specified that polyethylene glycol and NaOH, as reactants, greatly influenced the decomposition of PCBs. Nevertheless, zero valent iron had no effect, and H2O decreased the decomposition efficiency of PCBs. Furthermore, experimental results showed that at the optimum amounts of variables (PEG = 5.34g, NaOH= 1.17g, Fe= 0.6g, H2O= 0.8 ml, microwave power 800 w, 93% of PCBs were decomposed over the reaction duration of 6 min. Therefore, PCBs degradation efficiency without water rose up to 99.99% under the MW at 6 min. Conclusion: The results indicated that MW, PEG and NaOH were important variables on PCBs degradation from real waste transformer oil. It is therefore suggested that microwave radiation with the assistance of PEG and alkali can be introduced as a potential technology for PCBs removal from real waste PCB-contaminated oil.

  16. 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

  17. 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.

  18. Simulation of microwave heating of a composite part in an oven cavity

    Science.gov (United States)

    Tertrais, Hermine; Ibanez, Ruben; Barasinski, Anaïs; Ghnatios, Chady; Chinesta, Francisco

    2017-10-01

    Microwave (MW) technology relies on volumetric heating. Thermal energy is transferred to the material that can absorb it at specific frequencies. In this paper, a coupled thermic and electromagnetic model is proposed in order to simulate the emerging process of microwave heating for composite materials. Solving the problem in a laminated composite material requires a high degree of discretization in the thickness direction which is made possible by introducing the in-plane-out-of-plane decomposition approach using the Proper Generalized Decomposition (PGD).

  19. Atmospheric attenuation relative to earth-viewing orbital sensors. [atmospheric moisture effects on microwaves

    Science.gov (United States)

    Brown, S. C.; Jayroe, R. R., Jr.

    1973-01-01

    Earth viewing space missions offer exciting new possibilities in several earth resources disciplines - geography, hydrology, agriculture, geology, and oceanography, to name a few. A most useful tool in planning experiments and applying space technology to earth observation is a statistical description of atmospheric parameters. Four dimensional atmospheric models and a world wide cloud model are used to produce atmospheric attenuation models to predict degradation effects for all classes of sensors for application to earth sensing experiments from spaceborne platforms. To insure maximum utility and application of these products, the development of an interaction model of microwave energy and atmospheric variables provides a complete description of the effects of atmospheric moisture upon microwaves.

  20. Cryogenic pulsed inductive microwave magnetometer

    Science.gov (United States)

    Kos, A. B.; Nibarger, J. P.; Lopusnik, R.; Silva, T. J.; Celinski, Z.

    2003-05-01

    A cryogenic pulsed inductive microwave magnetometer is used to characterize the switching dynamics in thin-film magnetic materials at low temperatures and microwave frequencies. The system is contained inside a 20-cm-diam ultrahigh vacuum chamber and cooled by a cryopump that allows measurements between 20 and 350 K. A temperature controller regulates the sample temperature using two silicon diodes as sensors. Applied magnetic fields of up to 36 kA/m (450 Oe) are generated by a four-pole, water-cooled electromagnet with independent control of each axis. Magnetic switching in the sample is driven by high-speed current step pulses in a coplanar waveguide structure with the sample placed in a flip-chip configuration. A 20 GHz sampling oscilloscope is used to record the dynamics of the magnetic reorientation. The switching dynamics are given for a 10-nm-thick Ni-Fe film at 30 K in response to a 1 kA/m field step.

  1. Study of microwave components for an electron cyclotron resonance ...

    Indian Academy of Sciences (India)

    Keywords. Microwave system; microwave studio software; network analyser; electron cyclotron resonance ion source. ... of ∼13 eV was obtained. This article describes various aspects of the microwave system including design, fabrication, characterization and performance studies of the microwave components.

  2. Microwave Cooking: Knowledge, Attitudes, and Practices of California Foods Teachers.

    Science.gov (United States)

    Stalder, Laura D.; And Others

    1990-01-01

    A survey of 500 California secondary foods teachers (172 responses) indicated their understanding of microwave cooking principles and techniques and positive attitudes toward microwave cooking and safety. A majority used microwave instruction in their classrooms, although many indicated a need for ovens and microwave educational materials. (SK)

  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. A review of catalytic microwave pyrolysis of lignocellulosic biomass for value-added fuel and chemicals.

    Science.gov (United States)

    Morgan, Hervan Marion; Bu, Quan; Liang, Jianghui; Liu, Yujing; Mao, Hanping; Shi, Aiping; Lei, Hanwu; Ruan, Roger

    2017-04-01

    Lignocellulosic biomass is an abundant renewable resource and can be efficiently converted into bio-energy by a bio-refinery. From the various techniques available for biomass thermo-chemical conversion; microwave assisted pyrolysis (MAP) seems to be the very promising. The principles of microwave technology were reviewed and the parameters for the efficient production of bio-oil using microwave technology were summarized. Microwave technology by itself cannot efficiently produce high quality bio-oil products, catalysts are used to improve the reaction conditions and selectivity for valued products during MAP. The catalysts used to optimize MAP are revised in the development of this article. The origins for bio-oils that are phenol rich or hydrocarbon rich are reviewed and their experimental results were summarized. The kinetics of MAP is discussed briefly in the development of the article. Future prospects and scientific development of MAP are also considered in the development of this article. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Comparison of porcelain surface and flexural strength obtained by microwave and conventional oven glazing.

    Science.gov (United States)

    Prasad, Soni; Monaco, Edward A; Kim, Hyeongil; Davis, Elaine L; Brewer, Jane D

    2009-01-01

    Although the superior qualities of microwave technology are common knowledge in the industry, effects of microwave glazing of dental ceramics have not been investigated. The purpose of this study was to investigate the surface roughness and flexural strength achieved by glazing porcelain specimens in a conventional and microwave oven. Thirty specimens of each type of porcelain (Omega 900 and IPS d.Sign) were fabricated and sintered in a conventional oven. The specimens were further divided into 3 groups (n=10): hand polished (using diamond rotary ceramic polishers), microwave glazed, and conventional oven glazed. Each specimen was evaluated for surface roughness using a profilometer. The flexural strength of each specimen was measured using a universal testing machine. A 2-way ANOVA and Tukey HSD post hoc analysis were used to determine significant intergroup differences in surface roughness (alpha=.05). Flexural strength results were also analyzed using 2-way ANOVA, and the Weibull modulus was determined for each of the 6 groups. The surfaces of the specimens were subjectively evaluated for cracks and porosities using a scanning electron microscope (SEM). A significant difference in surface roughness was found among the surface treatments (P=.02). Follow-up tests showed a significant difference in surface roughness between oven-glazed and microwave-glazed treatments (P=.02). There was a significant difference in flexural strength between the 2 porcelains (Pmicrowave-glazed group was the highest (1.9) as compared to the other groups. The surface character of microwave-glazed porcelain was superior to oven-glazed porcelain. Omega 900 had an overall higher flexural strength than IPS d.Sign. Weibull distributions of flexural strengths for Omega 900 oven-glazed and microwave-glazed specimens were similar. SEM analysis demonstrated a greater number of surface voids and imperfections in IPS d. Sign as compared to Omega 900.

  6. [Study on Microwave Co-Pyrolysis of Low Rank Coal and Circulating Coal Gas].

    Science.gov (United States)

    Zhou, Jun; Yang, Zhe; Liu, Xiao-feng; Wu, Lei; Tian, Yu-hong; Zhao, Xi-cheng

    2016-02-01

    The pyrolysis of low rank coal to produce bluecoke, coal tar and gas is considered to be the optimal method to realize its clean and efficient utilization. However, the current mainstream pyrolysis production technology generally has a certain particle size requirements for raw coal, resulting in lower yield and poorer quality of coal tar, lower content of effective components in coal gas such as H₂, CH₄, CO, etc. To further improve the yield of coal tar obtained from the pyrolysis of low rank coal and explore systematically the effect of microwave power, pyrolysis time and particle size of coal samples on the yield and composition of microwave pyrolysis products of low rank coal through the analysis and characterization of products with FTIR and GC-MS, introducing microwave pyrolysis of low rank coal into the microwave pyrolysis reactor circularly was suggested to carry out the co-pyrolysis experiment of the low rank coal and coal gas generated by the pyrolysis of low rank coal. The results indicated that the yield of the bluecoke and liquid products were up to 62.2% and 26.8% respectively when the optimal pyrolysis process conditions with the microwave power of 800W, pyrolysis time of 40 min, coal samples particle size of 5-10 mm and circulating coal gas flow rate of 0.4 L · min⁻¹ were selected. The infrared spectrogram of the bluecoke under different microwave power and pyrolysis time overlapped roughly. The content of functional groups with -OH, C==O, C==C and C−O from the bluecoke through the pyrolysis of particle size coal samples had a larger difference. To improve microwave power, prolonging pyrolysis time and reducing particle size of coal samples were conducive to converting heavy component to light one into coal tar.

  7. Bathymetric surveys at highway bridges crossing the Missouri River in Kansas City, Missouri, using a multibeam echo sounder, 2010

    Science.gov (United States)

    Huizinga, Richard J.

    2010-01-01

    Bathymetric surveys were conducted by the U.S. Geological Survey, in cooperation with the Missouri Department of Transportation, on the Missouri River in the vicinity of nine bridges at seven highway crossings in Kansas City, Missouri, in March 2010. A multibeam echo sounder mapping system was used to obtain channel-bed elevations for river reaches that ranged from 1,640 to 1,800 feet long and extending from bank to bank in the main channel of the Missouri River. These bathymetric scans will be used by the Missouri Department of Transportation to assess the condition of the bridges for stability and integrity with respect to bridge scour. Bathymetric data were collected around every pier that was in water, except those at the edge of the water or in extremely shallow water, and one pier that was surrounded by a large debris raft. A scour hole was present at every pier for which bathymetric data could be obtained. The scour hole at a given pier varied in depth relative to the upstream channel bed, depending on the presence and proximity of other piers or structures upstream from the pier in question. The surveyed channel bed at the bottom of the scour hole was between 5 and 50 feet above bedrock. At bridges with drilled shaft foundations, generally there was exposure of the upstream end of the seal course and the seal course often was undermined to some extent. At one site, the minimum elevation of the scour hole at the main channel pier was about 10 feet below the bottom of the seal course, and the sides of the drilled shafts were evident in a point cloud visualization of the data at that pier. However, drilled shafts generally penetrated 20 feet into bedrock. Undermining of the seal course was evident as a sonic 'shadow' in the point cloud visualization of several of the piers. Large dune features were present in the channel at nearly all of the surveyed sites, as were numerous smaller dunes and many ripples. Several of the sites are on or near bends in the river

  8. Accelerated staining technique using kitchen microwave oven.

    Science.gov (United States)

    Mukunda, Archana; Narayan, T V; Shreedhar, Balasundhari; Shashidhara, R; Mohanty, Leeky; Shenoy, Sadhana

    2015-01-01

    Histopathological diagnosis of specimens is greatly dependent on good sample preparation and staining. Both of these processes is governed by diffusion of fluids and dyes in and out of the tissue, which is the key to staining. Diffusion of fluids can be accelerated by the application of heat that reduces the time of staining from hours to the minute. We modified an inexpensive model of kitchen microwave oven for staining. This study is an attempt to compare the reliability of this modified technique against the tested technique of routine staining so as to establish the kitchen microwave oven as a valuable diagnostic tool. Sixty different tissue blocks were used to prepare 20 pairs of slides for 4 different stains namely hematoxylin and eosin, Van Gieson's, 0.1% toluidine blue and periodic acid-Schiff. From each tissue block, two bits of tissues were mounted on two different slides. One slide was stained routinely, and the other stained inside a microwave. A pathologist evaluated the stained slides and the results so obtained were analyzed statistically. Microwave staining considerably cut down the staining time from hours to seconds. Microwave staining showed no loss of cellular and nuclear details, uniform-staining characteristics and was of excellent quality. The cellular details, nuclear details and staining characteristics of microwave stained tissues were better than or equal to the routine stained tissue. The overall quality of microwave-stained sections was found to be better than the routine stained tissue in majority of cases.

  9. [Eye heating caused by microwave ovens].

    Science.gov (United States)

    Leitgeb, N; Tropper, K

    1993-01-01

    To clarify the question as to whether microwave ovens represent a risk for the eyes, a worst-case situation was investigated in which it was assumed that a child observes the internal heating process with its eyes as close to the door of a microwave oven as it is possible to get. As expected, heating of the eyes was observed, which, however, was caused mainly by the conventional heating process rather than by microwave radiation. Significant microwave heating was observed only when increased scattered radiation was simulated by inactivating the safety contacts and opening the door of the microwave oven. When the door is opened to a clearly visible gap width (2.3 cm), the contribution of the microwave component to the overall temperature increase of 5 degrees C after one hour of continuous exposure did not exceed 16%. Even at the maximum possible door gap width which just did not cause the oven to switch off automatically (2.6 cm), 15 minutes of continuous exposure contributed only 50% to the 2 degrees C temperature increase. On the basis of these results, damage to the eye through the use of microwave ovens can be excluded.

  10. 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.

  11. The Use of Microwave Incineration to Process Biological Wastes

    Science.gov (United States)

    Sun, Sidney C.; Srinivasan, Venkatesh; Covington, Alan (Technical Monitor)

    1994-01-01

    The handling and disposal of solid waste matter that has biological or biohazardous components is a difficult issue for hospitals, research laboratories, and industry. NASA faces the same challenge as it is developing regenerative systems that will process waste materials into materials that can be used to sustain humans living in space for extended durations. Plants provide critical functions in such a regenerative life support scheme in that they photosynthesize carbon dioxide and water into glucose and oxygen. The edible portions of the plant provide a food source for the crew. Inedible portions can be processed into materials that are more recyclable. The Advanced Life Support Division at NASA Ames Research Center has been evaluating a microwave incinerator that will oxidize inedible plant matter into carbon dioxide and water. The commercially available microwave incinerator is produced by Matsushita Electronic Instruments Corporation of Japan. Microwave incineration is a technology that is simple, safe, and compact enough for home use. It also has potential applications for institutions that produce biological or biohazardous waste. The incinerator produces a sterile ash that has only 13% of the mass of the original waste. The authors have run several sets of tests with the incinerator to establish its viability in processing biological material. One goal of the tests is to show that the incinerator does not generate toxic compounds as a byproduct of the combustion process. This paper will describe the results of the tests, including analyses of the resulting ash and exhaust gases. The significance of the results and their implications on commercial applications of the technology will also be discussed.

  12. Phase-locking of multiple magnetic droplets by a microwave magnetic field

    Directory of Open Access Journals (Sweden)

    Chengjie Wang

    2017-05-01

    Full Text Available Manipulating dissipative magnetic droplet is of great interest for both the fundamental and technological reasons due to its potential applications in the high frequency spin-torque nano-oscillators. In this paper, a magnetic droplet pair localized in two identical or non-identical nano-contacts in a magnetic thin film with perpendicular anisotropy can phase-lock into a single resonance state by using an oscillating microwave magnetic field. This resonance state is a little away from the intrinsic precession frequency of the magnetic droplets. We found that the phase-locking frequency range increases with the increase of the microwave field strength. Furthermore, multiple droplets with a random initial phase can also be synchronized by a microwave field.

  13. Selective electroless plating of 3D-printed plastic structures for three-dimensional microwave metamaterials

    Science.gov (United States)

    Ishikawa, Atsushi; Kato, Taiki; Takeyasu, Nobuyuki; Fujimori, Kazuhiro; Tsuruta, Kenji

    2017-10-01

    A technique of selective electroless plating onto PLA-ABS (Polylactic Acid-Acrylonitrile Butadiene Styrene) composite structures fabricated by three-dimensional (3D) printing is demonstrated to construct 3D microwave metamaterials. The reducing activity of the PLA surface is selectively enhanced by the chemical modification involving Sn2+ in a simple wet process, thereby forming a highly conductive Ag-plated membrane only onto the PLA surface. The fabricated metamaterial composed of Ag-plated PLA and non-plated ABS parts is characterized experimentally and numerically to demonstrate the important bi-anisotropic microwave responses arising from the 3D nature of metallodielectric structures. Our approach based on a simple wet chemical process allows for the creation of highly complex 3D metal-insulator structures, thus paving the way toward the sophisticated microwave applications of the 3D printing technology.

  14. 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.

  15. 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.

  16. Microwave-driven Synthesis of Iron Oxide Nanoparticles for Fast Detection of Atherosclerosis.

    Science.gov (United States)

    Pellico, Juan; Ruiz-Cabello, Jesús; Herranz, Fernando

    2016-03-22

    A fast and reproducible microwave-driven protocol has been developed for the synthesis of neridronate-functionalized nanoparticles. Starting from the synthesis of hydrophobic nanoparticles, our method is based on an adaptation from thermal decomposition method to microwave driven synthesis. The new methodology produces a decrease in the reaction times in comparison with traditional procedures. Moreover, the use of the microwave technology increases the reproducibility of the reactions, something important from the point of view of clinical applications. The novelty of this iron oxide nanoparticle is the attachment of Neridronate. The use of this molecule leads a bisphosphonate moiety towards the outside of the nanoparticle that provides Ca2+ binding properties in vitro and selective accumulation in vivo in the atheroma plaque. The protocol allows the synthesis and plaque detection in about 3 hr since the initial synthesis from organic precursors. Their accumulation in the atherosclerotic area in less than 1 hr provides a contrast agent particularly suitable for clinical applications.

  17. Accelerator Technology Division annual report, FY 1989

    Energy Technology Data Exchange (ETDEWEB)

    1990-06-01

    This paper discusses: accelerator physics and special projects; experiments and injectors; magnetic optics and beam diagnostics; accelerator design and engineering; radio-frequency technology; accelerator theory and simulation; free-electron laser technology; accelerator controls and automation; and high power microwave sources and effects.

  18. Microwave Plasma Hydrogen Recovery System

    Science.gov (United States)

    Atwater, James; Wheeler, Richard, Jr.; Dahl, Roger; Hadley, Neal

    2010-01-01

    A microwave plasma reactor was developed for the recovery of hydrogen contained within waste methane produced by Carbon Dioxide Reduction Assembly (CRA), which reclaims oxygen from CO2. Since half of the H2 reductant used by the CRA is lost as CH4, the ability to reclaim this valuable resource will simplify supply logistics for longterm manned missions. Microwave plasmas provide an extreme thermal environment within a very small and precisely controlled region of space, resulting in very high energy densities at low overall power, and thus can drive high-temperature reactions using equipment that is smaller, lighter, and less power-consuming than traditional fixed-bed and fluidized-bed catalytic reactors. The high energy density provides an economical means to conduct endothermic reactions that become thermodynamically favorable only at very high temperatures. Microwave plasma methods were developed for the effective recovery of H2 using two primary reaction schemes: (1) methane pyrolysis to H2 and solid-phase carbon, and (2) methane oligomerization to H2 and acetylene. While the carbon problem is substantially reduced using plasma methods, it is not completely eliminated. For this reason, advanced methods were developed to promote CH4 oligomerization, which recovers a maximum of 75 percent of the H2 content of methane in a single reactor pass, and virtually eliminates the carbon problem. These methods were embodied in a prototype H2 recovery system capable of sustained high-efficiency operation. NASA can incorporate the innovation into flight hardware systems for deployment in support of future long-duration exploration objectives such as a Space Station retrofit, Lunar outpost, Mars transit, or Mars base. The primary application will be for the recovery of hydrogen lost in the Sabatier process for CO2 reduction to produce water in Exploration Life Support systems. Secondarily, this process may also be used in conjunction with a Sabatier reactor employed to

  19. 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

  20. 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