Science.gov

Sample records for sawing

  1. Saw palmetto

    MedlinePLUS

    ... or breast-feeding. Surgery: Saw palmetto might slow blood clotting. There is some concern that it might cause ... Talk with your health provider.Medications that slow blood clotting (Anticoagulant / Antiplatelet drugs)Saw palmetto might slow blood ...

  2. Power saw

    NASA Technical Reports Server (NTRS)

    Bradley, Jimmy D. (Inventor)

    1991-01-01

    A power saw is disclosed for space or robotic operations with jaw members for clamping to a work piece by an operation of a lever arm. The saw assembly is slidably mounted on the jaw assembly and fed into the work piece by a hand operated feed screw. The saw assembly includes a motor and gear belt. A current sensing circuit provides a current signal which actuates colored lights to visually depict the load on the saw blade during the cutting operations.

  3. Saw Palmetto

    MedlinePLUS

    ... et al. Saw palmetto for benign prostatic hyperplasia. New England Journal of Medicine . 2006;354(6):557–566. Croom EM Jr. Saw palmetto (Serenoa repens) . In: Coates P, Blackman M, Cragg G, et al., eds. Encyclopedia of Dietary Supplements . New York, NY: Marcel Dekker; 2005;635-644. National ...

  4. Gin saw wear test

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Most current gin saw manufacturers use a 1074 steel or similar as a basis to manufacture their saw blades. The saw teeth are individually punched on the edges of the blades and then the blade goes through a heat treating process prior to use. There are indications from other industries with similar ...

  5. See-Saw Jeans

    ERIC Educational Resources Information Center

    Sutton, Charlotte D.

    2005-01-01

    This article describes the following case: Pete Wilmington, Vice President of Sales for See-Saw Jeans for Kids, has wrapped up a deal with Wal-Mart to carry See-Saw Jeans for Kids in all Wal-Mart stores on a trial basis for the next year. See-Saw Jeans for Kids is a clothing manufacturer with sales of $41 million, but the Wal-Mart account has the

  6. See-Saw Jeans

    ERIC Educational Resources Information Center

    Sutton, Charlotte D.

    2005-01-01

    This article describes the following case: Pete Wilmington, Vice President of Sales for See-Saw Jeans for Kids, has wrapped up a deal with Wal-Mart to carry See-Saw Jeans for Kids in all Wal-Mart stores on a trial basis for the next year. See-Saw Jeans for Kids is a clothing manufacturer with sales of $41 million, but the Wal-Mart account has the…

  7. Electric arc saw apparatus

    DOEpatents

    Deichelbohrer, Paul R [Richland, WA

    1986-01-01

    A portable, hand held electric arc saw has a small frame for supporting an electrically conducting rotary blade which serves as an electrode for generating an electric arc to erode a workpiece. Electric current is supplied to the blade by biased brushes and a slip ring which are mounted in the frame. A pair of freely movable endless belts in the form of crawler treads stretched between two pulleys are used to facilitate movement of the electric arc saw. The pulleys are formed of dielectric material to electrically insulate the crawler treads from the frame.

  8. Rapid SAW Sensor Development Tools

    NASA Technical Reports Server (NTRS)

    Wilson, William C.; Atkinson, Gary M.

    2007-01-01

    The lack of integrated design tools for Surface Acoustic Wave (SAW) devices has led us to develop tools for the design, modeling, analysis, and automatic layout generation of SAW devices. These tools enable rapid development of wireless SAW sensors. The tools developed have been designed to integrate into existing Electronic Design Automation (EDA) tools to take advantage of existing 3D modeling, and Finite Element Analysis (FEA). This paper presents the SAW design, modeling, analysis, and automated layout generation tools.

  9. Electric arc saw apparatus

    DOEpatents

    Deichelbohrer, P.R.

    1983-08-08

    A portable, hand-held electric arc saw apparatus comprising a small frame for supporting an electrically conducting rotary blade which serves as an electrode for generating an electric arc between the blade and a workpiece of opposite polarity. Electrically conducting means are provided on said frame for transmitting current to said blade. A pair of freely movable endless belts in the form of crawler treads are employed to facilitate movement of the apparatus relative to the workpiece.

  10. Modeling of SAW Delay Lines

    NASA Technical Reports Server (NTRS)

    Wilson, William C.; Atkinson, Gary M.

    2007-01-01

    Integrated Vehicle Health Monitoring (IVHM) of aerospace vehicles requires rugged sensors having reduced volume, mass, and power that can be used to measure a variety of phenomena. Wireless systems are preferred when retro-fitting sensors onto existing vehicles. Surface Acoustic Wave (SAW) devices are capable of sensing: temperature, pressure, strain, chemical species, mass loading, acceleration, and shear stress. SAW technology is low cost, rugged, lightweight, and extremely low power. To aid in the development of SAW sensors for IVHM applications, a first order model of a SAW Delay line has been created.

  11. 29 CFR 570.65 - Occupations involved in the operations of circular saws, band saws, guillotine shears, chain saws...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., band saws, guillotine shears, chain saws, reciprocating saws, wood chippers, and abrasive cutting discs..., guillotine shears, chain saws, reciprocating saws, wood chippers, and abrasive cutting discs (Order 14). (a.... (iii) Wood chippers. (iv) Abrasive cutting discs. (3) The occupations of setting-up,...

  12. SAW correlator spread spectrum receiver

    DOEpatents

    Brocato, Robert W

    2014-04-01

    A surface acoustic wave (SAW) correlator spread-spectrum (SS) receiver is disclosed which utilizes a first demodulation stage with a chip length n and a second demodulation stage with a chip length m to decode a transmitted SS signal having a code length l=n.times.m which can be very long (e.g. up to 2000 chips or more). The first demodulation stage utilizes a pair of SAW correlators which demodulate the SS signal to generate an appropriate code sequence at an intermediate frequency which can then be fed into the second demodulation stage which can be formed from another SAW correlator, or by a digital correlator. A compound SAW correlator comprising two input transducers and a single output transducer is also disclosed which can be used to form the SAW correlator SS receiver, or for use in processing long code length signals.

  13. Lunar stone saw

    NASA Technical Reports Server (NTRS)

    Clark, Tom; Croker, Todd; Hines, Ken; Knight, Mike; Walton, Todd

    1988-01-01

    This project addresses the problem of cutting lunar stones into blocks to be used to construct shelters to protect personnel and equipment from harmful solar radiation. This plant will manufacture 6 in x 1 ft x 2 ft blocks and will be located near the south pole to allow it to be in the shade at all times. This design uses a computer controlled robot, a boulder handler that uses hydraulics for movement, a computer system that used 3-D vision to determine the size of boulders, a polycrystalline diamond tipped saw blade that utilizes radiation for cooling, and a solar tower to collect solar energy. Only two electric motors are used in this plant because of the heavy weight of electric motors and the problem of cooling them. These two motors will be cooled by thermoelectric cooling. All other motors and actuators are to be hydraulic. The architectural design for the building as well as the conceptual design of the machines for cutting the blocks are described.

  14. Review on SAW RFID tags.

    PubMed

    Plessky, Victor P; Reindl, Leonhard M

    2010-03-01

    SAW tags were invented more than 30 years ago, but only today are the conditions united for mass application of this technology. The devices in the 2.4-GHz ISM band can be routinely produced with optical lithography, high-resolution radar systems can be built up using highly sophisticated, but low-cost RF-chips, and the Internet is available for global access to the tag databases. The "Internet of Things," or I-o-T, will demand trillions of cheap tags and sensors. The SAW tags can overcome semiconductor-based analogs in many aspects: they can be read at a distance of a few meters with readers radiating power levels 2 to 3 orders lower, they are cheap, and they can operate in robust environments. Passive SAW tags are easily combined with sensors. Even the "anti-collision" problem (i.e., the simultaneous reading of many nearby tags) has adequate solutions for many practical applications. In this paper, we discuss the state-of-the-art in the development of SAW tags. The design approaches will be reviewed and optimal tag designs, as well as encoding methods, will be demonstrated. We discuss ways to reduce the size and cost of these devices. A few practical examples of tags using a time-position coding with 10(6) different codes will be demonstrated. Phase-coded devices can additionally increase the number of codes at the expense of a reduction of reading distance. We also discuss new and exciting perspectives of using ultra wide band (UWB) technology for SAW-tag systems. The wide frequency band available for this standard provides a great opportunity for SAW tags to be radically reduced in size to about 1 x 1 mm(2) while keeping a practically infinite number of possible different codes. Finally, the reader technology will be discussed, as well as detailed comparison made between SAW tags and IC-based semiconductor device. PMID:20211785

  15. SAW-Modulated Image Device

    NASA Technical Reports Server (NTRS)

    Benz, H. F.

    1985-01-01

    Imaging device uses surface-acoustic-wave (SAW) charge transfer for image readout. Spatial resolution of image changed electronically by changing frequency of applied signal. Surface acoustic waves create traveling longitudinal electric fields. These fields create potential wells that carry along stored charges. Charges injected into wells by photoelectric conversion when light strikes device.

  16. Reciprocating Saw for Silicon Wafers

    NASA Technical Reports Server (NTRS)

    Morrison, A. D.; Collins, E. R., Jr.

    1985-01-01

    Concept increases productivity and wafer quality. Cutting wafers from silicon ingots produces smooth wafers at high rates with reduced blade wear. Involves straight reciprocating saw blade and slight rotation of ingot between cutting strokes. Many parallel blades combined to cut many wafers simultaneously from ingot.

  17. Improved table-saw guard

    NASA Technical Reports Server (NTRS)

    Dunn, B. R.; Zebus, P. P.

    1980-01-01

    Guard makes lighter contact on materials being sawed. Cuts are better controlled, and damages to fragile foam-type materials are reduced. Overhead support makes it possible to perform slot and step cuts, and thick materials are pushed under guard with less force. Guard is transparent plastic enclosure held by side-attached overhead support arm.

  18. Reconstructing see-saw models

    SciTech Connect

    Ibarra, Alejandro

    2007-01-12

    In this talk we discuss the prospects to reconstruct the high-energy see-saw Lagrangian from low energy experiments in supersymmetric scenarios. We show that the model with three right-handed neutrinos could be reconstructed in theory, but not in practice. Then, we discuss the prospects to reconstruct the model with two right-handed neutrinos, which is the minimal see-saw model able to accommodate neutrino observations. We identify the relevant processes to achieve this goal, and comment on the sensitivity of future experiments to them. We find the prospects much more promising and we emphasize in particular the importance of the observation of rare lnic decays for the reconstruction of the right-handed neutrino masses.

  19. Two Problems with Table Saws

    ERIC Educational Resources Information Center

    Vautaw, William R.

    2008-01-01

    We solve two problems that arise when constructing picture frames using only a table saw. First, to cut a cove running the length of a board (given the width of the cove and the angle the cove makes with the face of the board) we calculate the height of the blade and the angle the board should be turned as it is passed over the blade. Second, to…

  20. Two Problems with Table Saws

    ERIC Educational Resources Information Center

    Vautaw, William R.

    2008-01-01

    We solve two problems that arise when constructing picture frames using only a table saw. First, to cut a cove running the length of a board (given the width of the cove and the angle the cove makes with the face of the board) we calculate the height of the blade and the angle the board should be turned as it is passed over the blade. Second, to

  1. Frequency Domain Modeling of SAW Devices

    NASA Technical Reports Server (NTRS)

    Wilson, W. C.; Atkinson, G. M.

    2007-01-01

    New SAW sensors for integrated vehicle health monitoring of aerospace vehicles are being investigated. SAW technology is low cost, rugged, lightweight, and extremely low power. However, the lack of design tools for MEMS devices in general, and for Surface Acoustic Wave (SAW) devices specifically, has led to the development of tools that will enable integrated design, modeling, simulation, analysis and automatic layout generation of SAW devices. A frequency domain model has been created. The model is mainly first order, but it includes second order effects from triple transit echoes. This paper presents the model and results from the model for a SAW delay line device.

  2. SAW Temperature Sensor on Quartz.

    PubMed

    Zhgoon, Sergei; Shvetsov, Alexander; Ancev, Ivan; Bogoslovsky, Sergei; Sapozhnikov, Gennadiy; Trokhimets, Konstantin; Derkach, Mikhail

    2015-06-01

    For biomedical applications, narrow temperature range and high sensor accuracy requirements define the need for high temperature sensitivity. Wireless SAW sensors connected to antennas need a reference element to account for changes in electromagnetic coupling between the transmitter and receiver antennas. A pair of sensors with different temperature sensitivities may serve as a self-referenced sensor assembly. This justifies the need for materials with useful SAW resonator properties and with the largest difference between temperature coefficients of frequency (TCF) for a resonator pair on a single substrate. We have identified several cuts of quartz having useful properties with a TCF difference up to 140 ppm/C for a pair of resonators on a single substrate. As a rule, placing such resonators on a single substrate requires their rotation by up to 90 relative to each other. The limited range of cuts presents a unique opportunity to place both resonators along the X+90 direction with one resonator using Bleustein-Gulyaev-Shimizu (BGS) waves (with electrodes placed along the x-axis) and the other one (with electrodes inclined by about 10 to the x-axis) using quasi-Rayleigh waves. These cuts are close to the 70Y cut where a high TCF difference is reached together with acceptable characteristics of the resonators. Resonators were designed for all useful cuts (including the 70Y cut) and tested. The use of different periods in reflectors and interdigital transducer (IDT) together with individual choice of gaps between reflectors and IDT meant achieving low spurious content in resonator responses. The quality factors reached values up to 3500 at central frequencies around 915 MHz for both BGS and quasi-Rayleigh types of waves. The measured difference of the TCF is about 138 ppm/C on 70Y cut that is close to the calculated value. PMID:26067041

  3. Apparatus for loading a band saw blade

    DOEpatents

    Reeves, Steven R. (49 Williams Ave., West Valley, NY 14171)

    1990-01-01

    A band saw blade is loaded between pairs of guide wheels upon tensioning the blade by guiding the blade between pairs of spaced guide plates which define converging slots that converge toward the guide wheels. The approach is particularly useful in loading blades on underwater band saw machines used to cut radioactive materials.

  4. Apparatus for loading a band saw blade

    DOEpatents

    Reeves, S.R.

    1990-03-20

    A band saw blade is loaded between pairs of guide wheels upon tensioning the blade by guiding the blade between pairs of spaced guide plates which define converging slots that converge toward the guide wheels. The approach is particularly useful in loading blades on underwater band saw machines used to cut radioactive materials. 2 figs.

  5. SAW based systems for mobile communications satellites

    NASA Technical Reports Server (NTRS)

    Peach, R. C.; Miller, N.; Lee, M.

    1993-01-01

    Modern mobile communications satellites, such as INMARSAT 3, EMS, and ARTEMIS, use advanced onboard processing to make efficient use of the available L-band spectrum. In all of these cases, high performance surface acoustic wave (SAW) devices are used. SAW filters can provide high selectivity (100-200 kHz transition widths), combined with flat amplitude and linear phase characteristics; their simple construction and radiation hardness also makes them especially suitable for space applications. An overview of the architectures used in the above systems, describing the technologies employed, and the use of bandwidth switchable SAW filtering (BSSF) is given. The tradeoffs to be considered when specifying a SAW based system are analyzed, using both theoretical and experimental data. Empirical rules for estimating SAW filter performance are given. Achievable performance is illustrated using data from the INMARSAT 3 engineering model (EM) processors.

  6. 27. William E. Barrett, Photographer, August 1975. TRIMMER SAWS LOOKING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    27. William E. Barrett, Photographer, August 1975. TRIMMER SAWS LOOKING BACK FROM SORTING DOCK. SAW BLADES ARE HIDDEN BY HINGED PARTITION. SPIRAL ROLLERS CARRY BOARDS FROM SAWS TO HANDLES. - Meadow River Lumber Company, Highway 60, Rainelle, Greenbrier County, WV

  7. 28. William E. Barrett, Photographer, August 1975. TRIMMER SAWS FOR ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    28. William E. Barrett, Photographer, August 1975. TRIMMER SAWS FOR CUTTING BOARDS TO LENGTH. SAWS IN FOREGROUND REMOVED. NOTE BELT DRIVE ON REMAINING SAW. - Meadow River Lumber Company, Highway 60, Rainelle, Greenbrier County, WV

  8. 3. AERIAL VIEW OF SAW MILL RIVER CULVERT. NEPPERHAN AVENUE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. AERIAL VIEW OF SAW MILL RIVER CULVERT. NEPPERHAN AVENUE IS AT LEFT, SLIGHTLY FILLED SAW MILL RIVER CULVERT IS ON RIGHT. - Old Croton Aqueduct, Saw Mill River Culvert, Spanning Nepperhan Avenue, Yonkers, Westchester County, NY

  9. 29 CFR 570.65 - Occupations involving the operation of circular saws, band saws, guillotine shears, chain saws...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... machine equipped with a moveable blade operated vertically and used to shear materials. The term shall not... moving blade that alternately changes direction on a linear cutting axis used for sawing materials....

  10. 29 CFR 570.65 - Occupations involving the operation of circular saws, band saws, guillotine shears, chain saws...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... machine equipped with a moveable blade operated vertically and used to shear materials. The term shall not... moving blade that alternately changes direction on a linear cutting axis used for sawing materials....

  11. 29 CFR 570.65 - Occupations involving the operation of circular saws, band saws, guillotine shears, chain saws...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... machine equipped with a moveable blade operated vertically and used to shear materials. The term shall not... moving blade that alternately changes direction on a linear cutting axis used for sawing materials....

  12. Parameterizable Library Components for SAW Devices

    NASA Technical Reports Server (NTRS)

    Wilson, William C.; Atkinson, Gary M.

    2006-01-01

    To facilitate quick fabrication of Surface Acoustic Wave (SAW) sensors we have found it necessary to develop a library of parameterizable components. This library is the first module in our strategy towards a design tool that is integrated into existing Electronic Design Automation (EDA) tools. This library is similar to the standard cell libraries found in digital design packages. The library cells allow the user to input the design parameters which automatically generate a detailed layout of the SAW component. This paper presents the results of our development of parameterizable cells for an InterDigitated Transducer (IDT), reflector, SAW delay line, and both one and two port resonators.

  13. Chemically sensitive interfaces on SAW devices

    SciTech Connect

    Ricco, A.J.; Martin, S.J.; Crooks, R.M.; Xu, Chuanjing; Allred, R.E.

    1993-11-01

    Using surface acoustic wave (SAW) devices, three approaches to the effective use of chemically sensitive interfaces that are not highly chemically selective have been examined: (1) molecular identification from time-resolved permeation transients; (2) using multifrequency SAW devices to determine the frequency dependence of analyte/film interactions; (3) use of an array of SAW devices bearing diverse chemically sensitive interfaces to produce a distinct response pattern for each analyte. In addition to their well-known sensitivity to mass changes (0.0035 monolayer of N{sub 2} can be measured), SAW devices respond to the mechanical and electronic properties of thin films, enhancing response information content but making a thorough understanding of the perturbation critical. Simultaneous measurement of changes in frequency and attenuation, which can provide the information necessary to determine the type of perturbation, are used as part of the above discrimination schemes.

  14. Versatile machine mills, saws light materials

    NASA Technical Reports Server (NTRS)

    Rauschl, J. A.

    1966-01-01

    Versatile milling/sawing machine performs angle cuts, flat and profile milling, machining of grooves and slots, and edge trimming of phenolic panels. The machine is mounted on rails above a table equipped with vacuum capability for holding workpieces.

  15. SAW Sensor for Fastener Failure Detection

    NASA Technical Reports Server (NTRS)

    Wilson, W. C.; Rogge, M. D.; Fisher, B.; Roller, M. J.; Malocha, D. M.

    2010-01-01

    The proof of concept for using surface acoustic wave (SAW) strain sensors in the detection of aircraft fastener failures is demonstrated. SAW sensors were investigated because they have the potential for the development of passive wireless systems. The SAW devices employed four orthogonal frequency coding (OFC) spread spectrum reflectors in two banks on a high temperature piezoelectric substrate. Three SAW devices were attached to a cantilever panel with removable side stiffeners. Damage in the form of fastener failure was simulated by removal of bolts from the side stiffeners. During testing, three different force conditions were used to simulate static aircraft structural response under loads. The design of the sensor, the panel arrangement and the panel testing results are reported. The results show that the sensors successfully detected single fastener failure at distances up to 54.6 cm from the failure site under loaded conditions.

  16. Using SAW Resonators in RF Oscillators

    NASA Technical Reports Server (NTRS)

    Westbrook, R. M.; Deboo, G. J.

    1983-01-01

    Surface-acoustic-wave (SAW) resonators used as frequency-determining elements in radio-frequency oscillators circuits. Oscillators are frequencymodulated, phase-modulated, or pulse-modulated. SAW resonators are especially applicable to low-power subminiature applications, such as biotelemetry and wind-tunnel instrumentation, where they advantageously replace crystals. Resonators are smaller than crystals and very thin--advantage where small package size is important.

  17. Pure shear horizontal SAW biosensor on langasite.

    PubMed

    Berkenpas, Eric; Bitla, Shivashanker; Millard, Paul; da Cunha, Mauricio Pereira

    2004-11-01

    The undetected introduction of pathogens into food or water supplies can produce grave consequences in terms of economic loss and human suffering. Sensitive and selective sensors capable of quickly detecting microbial pathogens are urgently needed to limit the effects of bioterrorist incidents, accidents, or pollution. Shear horizontal surface acoustic wave (SH SAW) devices provide an attractive platform for the design of microbial biosensors that function in liquid media, where Rayleigh-type modes are rapidly attenuated. This paper reports on an exploratory SH SAW delay line designed and fabricated on langasite, La3Ga5SiO14 (LGS), along the novel Euler propagation direction (0 degrees, 22 degrees, 90 degrees). A liquid chamber was fabricated and attached to the top surface, and the device was submitted to liquid and biochemical tests. Moderate (6 dB) additional attenuation of the transmission coefficient, /S21/, was consistently observed when the SH SAW delay line was assembled in the test fixture and submitted to the liquid tests, indicating that LGS is an attractive candidate for liquid sensing. Sensor selectivity can be achieved by integrating the LGS SH SAW delay line with a biochemical recognition layer. A test setup was implemented for the characterization of LGS SH SAW-based biosensors. The delay line response to biomolecule binding was shown by detection of sequential binding of proteins to the SH SAW device delay path. The biotinylated sensor was exposed sequentially to biotin-binding deglycosylated avidin, biotin-modified rabbit IgG, and goat anti-rabbit IgG antibody. As each protein was bound to the sensing surface, marked changes in the delay-line phase were recorded. The reported results demonstrate the capability of these devices to act as biochemical detectors in aqueous solutions, and this work represents the first effort using the novel material LGS in SAW-based biosensor technology. PMID:15600083

  18. Suitability of three saws for minimally invasive bone cutting.

    PubMed

    Kong, Chris; Trejos, Ana Luisa; Naish, Michael D; Patel, Rajni V; Leitch, K Kellie

    2010-03-01

    This study compares 3 different saw types to determine which is best suited for integration into a minimally invasive bone saw. A handheld electric jigsaw, a coping saw, and a Gigli saw were used to cut into porcine ilium. Heat generated was measured using a thermocouple, and forces applied during cutting were recorded using a force/torque sensor. The coping saw generated an average maximum temperature that was 26 degrees C less than that generated using the jigsaw (P < .001) and 14 degrees C less than that for the Gigli saw (P < .001). On average, the maximum force applied through the coping saw was 14 N less than that through the jigsaw (P < .001) and 18 N less than that through the Gigli saw (P < .001). Out of the 3 saws tested, the coping saw is optimal for cutting bone based on heat generation and required force. PMID:20034976

  19. Passive Wireless SAW Sensors for IVHM

    NASA Technical Reports Server (NTRS)

    Wilson, William C.; Perey, Daniel F.; Atkinson, Gary M.; Barclay, Rebecca O.

    2008-01-01

    NASA aeronautical programs require integrated vehicle health monitoring (IVHM) to ensure the safety of the crew and the vehicles. Future IVHM sensors need to be small, light weight, inexpensive, and wireless. Surface acoustic wave (SAW) technology meets all of these constraints. In addition it operates in harsh environments and over wide temperature ranges, and it is inherently radiation hardened. This paper presents a survey of research opportunities for universities and industry to develop new sensors that address anticipated IVHM needs for aerospace vehicles. Potential applications of passive wireless SAW sensors from ground testing to high altitude aircraft operations are presented, along with some of the challenges and issues of the technology.

  20. High Temperature Langasite SAW Oxygen Sensor

    SciTech Connect

    Zheng, Peng; Chin, Tao-Lun; Greve, David; Oppenheim, Irving; Malone, Vanessa; Cao, Limin

    2011-08-01

    High-temperature langasite SAW oxygen sensors using sputtered ZnO as a resistive gas-sensing layer were fabricated and tested. Sensitivity to oxygen gas was observed between 500C to 700C, with a sensitivity peak at about 625C, consistent with the theoretical predictions of the acoustoelectric effect.

  1. Enhanced Magnetostrictively Transduced SAW Devices - Measurements & Applications

    NASA Astrophysics Data System (ADS)

    Woo, Noble C.

    2005-03-01

    Surface acoustic wave (SAW) transducers can be made with magnetic materials using magnetostriction as a means of electromechanical coupling. Unlike conventional piezoelectrically transduced SAW devices, the magnetically transduced SAWs do not require an exotic single-crystal substrate or high temperature processing, and therefore may be easily integrated into Si-based integrated circuits. These devices have many potential applications, biosensors being one of the most promising. When the substrate between a transmitter and a detector transducer is functionalized with specific bio-receptors, a binding event will affect propagation of the SAW wave that can be detected with simple electronics. In previous MTSAW devices, the magnetomechanical coupling was found to be poor, resulting in insufficient signal amplitude. To obtain better performance, we are studying the use of alternative magnetostrictive materials including an amorphous CoFeTaZr alloy, CoNbZr, and compositions in the Terfernol family (TbFe2, etc.). We are using combinatorial materials science (continuous composition spread approach) to identify optimum alloy compositions. The devices are also being redesigned to yield better performance.

  2. High-temperature langasite SAW oxygen sensor.

    PubMed

    Zheng, Peng; Chin, Tao-Lun; Greve, David; Oppenheim, Irving; Malone, Vanessa; Cao, Limin

    2011-08-01

    High-temperature langasite SAW oxygen sensors using sputtered ZnO as a resistive gas-sensing layer were fabricated and tested. Sensitivity to oxygen gas was observed between 500C to 700C, with a sensitivity peak at about 625C, consistent with the theoretical predictions of the acoustoelectric effect. PMID:21859571

  3. Mixed orthogonal frequency coded SAW RFID tags.

    PubMed

    Gallagher, Mark W; Malocha, Donald C

    2013-03-01

    Orthogonal frequency coded (OFC) SAW radio-frequency identification (RFID) tags are currently being explored as a multi-sensor platform because of their passive spread-spectrum operation, low loss, and resilience in harsh environments. Ongoing research continues to search for robust device embodiments that increase the number of identifiable codes, in the presence of intersymbol interference, while maintaining reasonable device lengths. This paper presents a technique that shortens the SAW response length while preserving code diversity and bandwidth by utilizing a multi-track SAW configuration. These new devices allow the time response of multiple OFC chips to overlap and yield a mixed-frequency chip having the sum of the chip bandwidths but shorter overall time response. The theoretical development is presented and examples are discussed for these new mixed orthogonal frequency coded (MOFC) SAW devices. Experimental results for MOFC sensors, fabricated on YZ-LiNbO3, with a 7% fractional bandwidth and five chip frequencies in three cells, provide a good contrast to similar OFC designs. Experimental results are presented for the simultaneous operation of eight wireless temperature sensors--four OFC and four MOFC--in a 915-MHz wireless correlator receiver system, highlighting the ability of these devices to operate in the same system. PMID:23475925

  4. Attenuation of laser generated SAWs in heated PMMA material

    NASA Astrophysics Data System (ADS)

    Li, Jia; Liu, Jing; Dong, Liming; Shen, Zhonghua; Yuan, Ling

    2010-08-01

    To investigate the propagation of Surface Acoustic Waves (SAWs) in the heated region of Polymethyl Methacrylate (PMMA), through the thermoelastic mechanism, a finite element model is put forward to simulate laser inducing SAWs in PMMA. Meanwhile, the propagation of SAWs through the heated region of PMMA is investigated experimentally: a Nd:YAG laser is used to excite SAWs and a polyvinylindene fluoride (PVDF) transducer is used to detect SAWs. The simulation and experimental results are in good agreement. SAWs have a significant attenuation when they propagate through the heated region of PMMA.

  5. Improved Multiple-DOF SAW Piezoelectric Motors

    NASA Technical Reports Server (NTRS)

    Bar-Cohen, Yoseph; Bao, Xiaoqi; Hull, Anthony; Wright, John

    2003-01-01

    Surface-acoustic-wave (SAW) piezoelectric motors of a proposed type would be capable of operating in multiple degrees of freedom (DOFs) simultaneously and would be amenable to integration into diverse structures and mechanisms. These motors would be compact and structurally simple and would not contain bearings or lead screws. One example of a particularly useful motor of this type would be a two-dimensional- translation stage. Another such example would be a self-actuated spherical joint that could be made to undergo controlled, simultaneous rotations about two orthogonal axes: Such a motor could serve as a mechanism for aiming an "eyeball" camera or as a compact transducer in, and an integral part of, a joint in a robot arm. The multiple-DOF SAW piezoelectric motors as now proposed would be successors to the ones reported in "Multiple-DOF Surface-Acoustic-Wave Piezoelectric Motors" (NPO-20735), NASA Tech Briefs, Vol. 24, No. 12 (December 2000), page 5b. The basic principle of operation of a multiple-DOF SAW piezoelectric motor is a straightforward extension of that of single-DOF SAW piezoelectric motors, which have been reported in several previous NASA Tech Briefs articles: For example, in the case of a linear SAW piezoelectric motor, piezoelectric transducers at opposite ends of a stator excite surface acoustic waves that travel along the surface of the stator. An object (denoted the slider) is pressed against the stator with sufficient pressure (in practice .300 MPa) that it remains in frictional contact with the stator at all times. The slider rides the crests of the waves and is thereby made to move along the surface of the stator. The direction of motion (forward or backward) is controlled by selecting the relative phase of waves generated by the two piezoelectric transducers. The speed increases with the amplitude of the waves and thus with the magnitude of the voltage applied to the transducers.

  6. 8. GENERAL VIEW OF SHINGLE CUTTING SAWS THAT HANDLE BOLTS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. GENERAL VIEW OF SHINGLE CUTTING SAWS THAT HANDLE BOLTS AFTER DEBARKING; AFTER DEBARKING THE BOLTS ARE SENT TO THE SHINGLE WEAVER FOR SAWING - Lester Shingle Mill, 1602 North Eighteenth Street, Sweet Home, Linn County, OR

  7. 32. TRIM SAWS IN BACKGROUND, VIEW FROM SOUTH WEST. NOTE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    32. TRIM SAWS IN BACKGROUND, VIEW FROM SOUTH WEST. NOTE WASTE CONVEYOR IN FOREGROUND, CANT ROLL CASE TO BEAM SAW, THEN ROLL CASE FROM EDGER IN MIDDLE GROUND. - Hull-Oakes Lumber Company, 23837 Dawson Road, Monroe, Benton County, OR

  8. 15. Basement level of Saw Mill looking northeast into the ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    15. Basement level of Saw Mill looking northeast into the turbine pit. Headrace for the Grist Mill is beyond the wall to the right. - Sugar River Grist Mill & Saw Mill, 159 Main Street, Claremont, Sullivan County, NH

  9. 3. ELEVATION OF THE OAK VIADUCT, LOOKING NORTH ON SAW ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. ELEVATION OF THE OAK VIADUCT, LOOKING NORTH ON SAW MILL RUN BOULEVARD - Pittsburgh & Castle Shannon Railroad, Oak Viaduct, Overbrook Trolley Line, crossing Saw Mill Run Boulevard & Colerain Street, Pittsburgh, Allegheny County, PA

  10. Integrated circuit for SAW and MEMS sensors

    NASA Astrophysics Data System (ADS)

    Fischer, Wolf-Joachim; Koenig, Peter; Ploetner, Matthias; Hermann, Rudiger; Stab, Helmut

    2001-11-01

    The sensor processor circuit has been developed for hand-held devices used in industrial and environmental applications, such as on-line process monitoring. Thereby devices with SAW sensors or MEMS resonators will benefit from this processor especially. Up to 8 sensors can be connected to the circuit as multisensors or sensor arrays. Two sensor processors SP1 and SP2 for different applications are presented in this paper. The SP-1 chip has a PCMCIA interface which can be used for the program and data transfer. SAW sensors which are working in the frequency range from 80 MHz to 160 MHz can be connected to the processor directly. It is possible to use the new SP-2 chip fabricated in a 0.5(mu) CMOS process for SAW devices with a maximum frequency of 600 MHz. An on-chip analog-digital-converter (ADC) and 6 PWM modules support the development of high-miniaturized intelligent sensor systems We have developed a multi-SAW sensor system with this ASIC that manages the requirements on control as well as signal generation and storage and provides an interface to the PC and electronic devices on the board. Its low power consumption and its PCMCIA plug fulfil the requirements of small size and mobility. For this application sensors have been developed to detect hazardous gases in ambient air. Sensors with differently modified copper-phthalocyanine films are capable of detecting NO2 and O3, whereas those with a hyperbranched polyester film respond to NH3.

  11. Microsystem packaging of an RF SAW correlator.

    SciTech Connect

    Palmer, David A.; Brocato, Robert Wesley; Studor, George F.

    2005-01-01

    An electrically programmable surface acoustic wave (SAW) correlator was recently completed from design through small scale production in support of low power space-based communications for NASA. Three different versions of this RF microsystem were built to satisfy design requirements and overcome packaging and system reliability related issues. Flip-chip packaging and conventional thick film hybrid assembly techniques are compared in the fabrication of this microsystem.

  12. Surface-acoustic-wave (SAW) flow sensor.

    PubMed

    Joshi, S G

    1991-01-01

    The use of a surface-acoustic-wave (SAW) device to measure the rate of gas flow is described. A SAW oscillator heated to a suitable temperature above ambient is placed in the path of a flowing gas. Convective cooling caused by the gas flow results in a change in the oscillator frequency. A 73-MHz oscillator fabricated on 128 degrees rotated Y-cut lithium niobate substrate and heated to 55 degrees C above ambient shows a frequency variation greater than 142 kHz for flow-rate variation from 0 to 1000 cm(3)/min. The output of the sensor can be calibrated to provide a measurement of volume flow rate, pressure differential across channel ports, or mass flow rate. High sensitivity, wide dynamic range, and direct digital output are among the attractive features of this sensor. Theoretical expressions for the sensitivity and response time of the sensor are derived. It is shown that by using ultrasonic Lamb waves, propagating in thin membranes, a flow sensor with faster response than a SAW sensor can be realized. PMID:18267569

  13. Sawing performance comparison of brazed and sintered diamond wires

    NASA Astrophysics Data System (ADS)

    Huang, Guoqin; Xu, Xipeng

    2013-03-01

    Great attention has been paid on fabricating diamond wire by using the brazing diamond because of its strong chemical bonding strength and controllability of grits distribution. Although several serving performances of brazed diamond wire have been reported, seldom do these studies refer to its process characteristics. Sawing performances of a brazed diamond wire are investigated and compared with those of a sintered diamond wire on a wire saw machine. The surface topographies of beads selected from the two wires are micro observed before sawing. The sawing tests are carried out in constant feed rate feeding(CFF) and constant normal force feeding(CNFF). In CFF test, sawing force, power, and the cut depths of positions on contact curve are measured. Then, coupled with the observations of beads topographies, sawing force and its ratio, relations of power against material removal rate, and contact curve linearity are compared and discussed. In CNFF test, the sawing rates of the two wires are investigated. The results indicate that the brazed wire performs with lower sawing force(less 16% of tangential force and 28% of normal force), more energy efficiency(nearly one-fifth of sawing power is saved), at a higher sawing rate (the rate is doubled) and with better contact curve linearity as compared with the sintered wire. This proposed research experimentally evaluates the sawing performances of brazed diamond wire from the aspect of process parameters, which can provide a basis for popularizing the brazed diamond wire.

  14. Controlling dust from concrete saw cutting.

    PubMed

    Shepherd, Susan; Woskie, Susan

    2013-01-01

    Cutting concrete with gas-powered saws is ubiquitous in the construction industry and a source of exposure to respirable crystalline silica. Volunteers from the New England Laborers Training Center were recruited to participate in a field experiment examining dust reductions through the use of water, from a hose and from a sprayer, as a dust control. In four series of tests, reinforced concrete pipe was cut under both "dry" and "wet" control conditions. Overall, the geometric mean respirable dust concentration for "dry" cutting (14.396 mg/m) exceeded both types of water-based controls by more than tenfold. Wet cutting reduced the respirable dust concentration by 85% compared with dry cutting when comparing tests paired by person and saw blade (n = 79 pairs). Using a respirable cyclone, a total of 178 samples were taken. Due to the high variability in dust exposure found in this and other studies of saw cutting, the data were examined for potential exposure determinants that contribute to that variability. Using mixed models, three fixed effects were statistically significant: control condition, worker experience, and location. A random effect for subject was included in the model to account for repeated measures. When each of the significant fixed effects was included with the random effect, it was apparent that inclusion of worker experience or location reduced the between-worker component of exposure variability, while inclusion of control condition (wet vs. dry) explained a large portion of the within-subject variability. Overall, the fixed effect variable for control condition explained the largest fraction of the total exposure variability. PMID:23252479

  15. Thermal Imaging of Medical Saw Blades and Guides

    SciTech Connect

    Dinwiddie, Ralph Barton; Steffner, Thomas E

    2007-01-01

    Better Than New, LLC., has developed a surface treatment to reduce the friction and wear of orthopedic saw blades and guides. The medical saw blades were thermally imaged while sawing through fresh animal bone and an IR camera was used to measure the blade temperature as it exited the bone. The thermal performance of as-manufactured saw blades was compared to surface-treated blades, and a freshly used blade was used for temperature calibration purposes in order to account for any emissivity changes due to organic transfer layers. Thermal imaging indicates that the treated saw blades cut faster and cooler than untreated blades. In orthopedic surgery, saw guides are used to perfectly size the bone to accept a prosthesis. However, binding can occur between the blade and guide because of misalignment. This condition increases the saw blade temperature and may result in tissue damage. Both treated ad untreated saw guides were also studied. The treated saw guide operated at a significantly lower temperature than untreated guide. Saw blades and guides that operate at a cooler temperature are expected to reduce the amount of tissue damage (thermal necrosis) and may reduce the number of post-operative complications.

  16. Saw + LMJ: a hybrid semiconductor dicing solution

    NASA Astrophysics Data System (ADS)

    Richerzhagen, Bernold; Plankensteiner, Martin; Kling, Notker U.; Stay, Keith; Brulé, Arnaud

    2008-02-01

    The concept of combining the Laser MicroJet (R) (LMJ) water jet-guided laser with a standard industrial diamond blade saw was first proposed early in 2006. The idea has now been taken a step forward with a joint project between Synova SA and Disco Hi-Tech Europe GmbH. The hybrid machine being developed integrates an LMJ module in place of the second blade saw on a Disco dual-spindle machine. The resulting machine will be fully capable of sequencing the different processes to carry out dicing of complex and layered semiconductors wafer, in any possible combination. It will be possible to program both processes to run independently in parallel or allow sequential operation during the same cutting pass. This extraordinary flexibility, combined with the speed advantages, quality of material cutting and simplification in processing in a fully automatic mode for up to 300 mm wafers, all now available in a single machine, will greatly benefit the manufacturing community. This paper will provide some insight into the design and operation of the hybrid machine and some examples of the improvements gained from its use.

  17. Programmable SAW development :Sandia/NASA project final report.

    SciTech Connect

    Brocato, Robert Wesley

    2004-10-01

    This report describes a project to develop both fixed and programmable surface acoustic wave (SAW) correlators for use in a low power space communication network. This work was funded by NASA at Sandia National Laboratories for fiscal years 2004, 2003, and the final part of 2002. The role of Sandia was to develop the SAW correlator component, although additional work pertaining to use of the component in a system and system optimization was also done at Sandia. The potential of SAW correlator-based communication systems, the design and fabrication of SAW correlators, and general system utilization of those correlators are discussed here.

  18. A new surface acoustic wave (SAW) delay line sensor

    NASA Astrophysics Data System (ADS)

    Jha, Shashank S.; Yadava, R. D. S.

    2013-06-01

    We propose a new configuration for SAW chemical sensing. A polymer coated SAW delay line device provides the coupling for synchronization of two stable self-sustained limit cycle oscillators. The dependence of synchronization frequency on the SAW delay time has been made the basis for chemical sensing. The analysis has carried out under conditions of weak phase coupling [1]. The dependence of synchronization modes on coupling parameters is analyzed. The sensitivity of a synchronization branch for vapor sorption induced delay perturbations is analyzed. This analysis shows the possibility of realizing high performance SAW sensors by this approach.

  19. Building SAWE Capability as an ANSI Accredited Standards Developer

    NASA Technical Reports Server (NTRS)

    Cerro, Jeffrey A.; Davis, Ed; Peterson, Eric; Griffiths, William T.; Brooks, Andy; Stratton, Bonnie; Attar, Jose

    2014-01-01

    This paper presents a 2014 status of the Society of Allied Weight Engineers' process towards becoming an Accredited Standards Developer (ASD) under certification by the United States American National Standards Institute (ANSI). Included is material from the committee's 2013 International presentation, current status, and additional general background material. The document strives to serve as a reference point to assist SAWE Recommended Practice and Standards developers in negotiating United States Standards Strategy, international standards strategy, and the association of SAWE standards and recommended practices to those efforts. Required procedures for SAWE to develop and maintain Recommended Practices and ANSI/SAWE Standards are reviewed.

  20. Discriminating neutrino see-saw models

    NASA Astrophysics Data System (ADS)

    Hirsch, M.; King, S. F.

    2001-09-01

    We consider how well current theories can predict neutrino mass and mixing parameters, and construct a statistical discriminator which allows us to compare different models to each other. As an example we consider see-saw models based on family symmetry, and single right-handed neutrino dominance, and compare them to each other and to the case of neutrino anarchy with random entries in the neutrino Yukawa and Majorana mass matrices. The predictions depend crucially on the range of the undetermined coefficients over which we scan, and we speculate on how future theories might lead to more precise predictions for the coefficients and hence for neutrino observables. Our results indicate how accurately neutrino masses and mixing angles need to be measured by future experiments in order to discriminate between current models.

  1. A monolithic SAW-charge transfer device

    NASA Technical Reports Server (NTRS)

    Papanicolaou, N. A.; Lin, H. C.

    1978-01-01

    Surface acoustic waves excited in a Si-SiO2-ZnO layered structure can produce a traveling electric field in the silicon substrate. Charges stored in the traveling potential wells can be transferred at high speed and density and with less complexity. The monolithic structure under investigation for the SAW-charge transfer device consists of a silicon substrate, a thin silicon dioxide insulating layer on top of which a ZnO piezoelectric film is deposited by sputtering. The surface acoustic waves are excited by interdigital transducers. The signal charge is injected into traveling potential wells that travel with the velocity of sound. Conditions for the transfer of the charges by the traveling wells are analyzed. A surface acoustic wave program was used to determine the optimum structure dimensions and transducer configuration which will produce the highest coupling in the excitation of the piezoelectric waves.

  2. Current developments in SAW oscillator stability

    NASA Technical Reports Server (NTRS)

    Parker, T. E.

    1977-01-01

    The results reported were obtained with two port delay lines and resonators used in a simple feedback oscillator. The feedback oscillator employed inherently operates with the amplifier in a saturated condition and, therefore, the AM noise is suppressed. Consequently the dominant noise is FM. Generally, it can be concluded that for very narrow-band, or fixed-frequency applications, the resonator-type oscillator will give the best noise performance. For applications where tunability and linearity are important, the delay-line-type oscillator may give the best performance. There have been no significant improvements in oscillator temperature stability. The only two demonstrated materials for temperature stable SAW oscillators are ST-cut quartz and the SiO2/LiTaO3 overlay structure. Aging tests have been going on for the past two-and-a-half years and it has become obvious that the observed aging rates are largely related to cleaning and packaging.

  3. Recycling SAW slag proves reliable and repeatable

    SciTech Connect

    Beck, H.P.; Jackson, A.R.

    1996-06-01

    Submerged arc welding (SAW) slag is recycled by taking the fused part of the slag after welding and processing it in a manner that allows it to be reused for the same SAW operation. This slag recycling process has been around the welding industry for many years, and trial-and-error experimentation through the years has made it a reliable and accepted process. Two major reasons why a welding manufacturer would consider the use of recycled submerged arc welding slag are cost savings and the environment. The cost of processing recycled slag is less than the purchase of new flux from the manufacturer. Many times this can amount to savings of 50% or greater. Savings can also be realized by eliminating the need to collect the slag and have it removed to an approved landfill. Environmentally, recycling slag minimizes the use of nonrenewable resources such as minerals, and it reduces the mass of material that must be sent to a landfill. It should be noted, though, that in most recycling processes there is some loss in weight, and not all the slag is processed into reusable flux. Also, there is magnetic separation during processing in which magnetic impurities are removed and disposed of as waste. An average for this loss is 25% of the total weight processed. To realize all of the advantages of recycling, it is essential that the process is performed properly and according to the standards established by industry. Below are steps required for recycling slag as established by two standards setting organizations.

  4. Impact of gin saw tooth design on textile processing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Toothed gin saws have been used to separate cotton fiber from the seed for over 200 years. There have been many saw tooth designs developed over the years. Most of these designs were developed by trial and error. A complete and scientific analysis of tooth design has never been done. It is not k...

  5. New developments for SAW channelization for mobile satellite payloads

    NASA Technical Reports Server (NTRS)

    Peach, R. C.; Mabson, P.

    1995-01-01

    The use of SAW technology in mobile communication payloads is becoming widely accepted by the industry since being pioneered by Inmarsat for its third generation of satellites. This paper presents new developments in this area, including broadband processors of the Inmarsat 3 type, and the use of SAW filters at L-band. It is demonstrated that SAW processors have considerable potential for increasing the capacity of future communications payloads, while allowing fully transparent operation without any restriction on traffic type or modulation format. In addition to the evolutionary development of Inmarsat type processors, new SAW applications have also emerged recently. Therefore, despite the rapid changes in the industry, it is predicted that SAW processing has a strong future in satellite communications.

  6. Preliminary experiments on SAW based magnetization switching of nanomagnets

    NASA Astrophysics Data System (ADS)

    Sampath, Vimal; D'Souza, Noel; Bandyopadhyay, Supriyo; Atulasimha, Jayasimha

    2015-03-01

    Magnetization rotation in micron-sized ferromagnetic elements, using Surface Acoustic Waves (SAW), has been demonstrated experimentally while the use of SAW to lower the energy dissipation in switching of nanomagnets with spin transfer torque has been studied theoretically. Furthermore, SAW can be used to ``Bennett clock'' an array of nanomagnets in nanomagnetic logic without requiring lithographic contacts to individual nanomagnets. We report preliminary experiments on use of SAW to switch magnetostrictive Co nanomagnets grown on bulk 128 Y-cut lithium niobate. Switching is studied by imaging the nanomagnets' magnetic states with Magnetic Force Microscopy (MFM) before and after the SAW waves interact with them. Switching of single, isolated nanomagnets of various sizes, and dipole coupled nanomagnets implementing a Boolean NOT gate, is studied. This work is supported by the US National Science Foundation under the SHF-Small Grant CCF-1216614, CAREER Grant CCF-1253370, NEB 2020 Grant ECCS-1124714 and SRC under NRI Task 2203.001.

  7. 29 CFR 570.65 - Occupations involved in the operations of circular saws, band saws, and guillotine shears (Order...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... teeth on the periphery, mounted on shafting, and used for sawing materials. (5) The term band saw shall mean a machine equipped with an endless steel band having a continuous series of notches or teeth... equipped with an endless steel band having a continuous series of notches or teeth, running over wheels...

  8. Fatty acid and phytosterol content of commercial saw palmetto supplements.

    PubMed

    Penugonda, Kavitha; Lindshield, Brian L

    2013-09-01

    Saw palmetto supplements are one of the most commonly consumed supplements by men with prostate cancer and/or benign prostatic hyperplasia (BPH). Some studies have found significant improvements in BPH and lower urinary tract symptoms (LUTS) with saw palmetto supplementation, whereas others found no benefits. The variation in the efficacy in these trials may be a result of differences in the putative active components, fatty acids and phytosterols, of the saw palmetto supplements. To this end, we quantified the major fatty acids (laurate, myristate, palmitate, stearate, oleate, linoleate) and phytosterols (campesterol, stigmasterol, β-sitosterol) in 20 commercially available saw palmetto supplements using GC-FID and GC-MS, respectively. Samples were classified into liquids, powders, dried berries, and tinctures. Liquid saw palmetto supplements contained significantly higher (p < 0.05) concentrations of total fatty acids (908.5 mg/g), individual fatty acids, total phytosterols (2.04 mg/g), and individual phytosterols, than the other supplement categories. Powders contained significantly higher (p < 0.05) concentrations of total fatty acids than tinctures, which contain negligible amounts of fatty acids (46.3 mg/g) and phytosterols (0.10 mg/g). Our findings suggest that liquid saw palmetto supplements may be the best choice for individuals who want to take a saw palmetto supplement with the highest concentrations of both fatty acids and phytosterols. PMID:24067389

  9. Fatty Acid and Phytosterol Content of Commercial Saw Palmetto Supplements

    PubMed Central

    Penugonda, Kavitha; Lindshield, Brian L.

    2013-01-01

    Saw palmetto supplements are one of the most commonly consumed supplements by men with prostate cancer and/or benign prostatic hyperplasia (BPH). Some studies have found significant improvements in BPH and lower urinary tract symptoms (LUTS) with saw palmetto supplementation, whereas others found no benefits. The variation in the efficacy in these trials may be a result of differences in the putative active components, fatty acids and phytosterols, of the saw palmetto supplements. To this end, we quantified the major fatty acids (laurate, myristate, palmitate, stearate, oleate, linoleate) and phytosterols (campesterol, stigmasterol, ?-sitosterol) in 20 commercially available saw palmetto supplements using GC-FID and GC-MS, respectively. Samples were classified into liquids, powders, dried berries, and tinctures. Liquid saw palmetto supplements contained significantly higher (p < 0.05) concentrations of total fatty acids (908.5 mg/g), individual fatty acids, total phytosterols (2.04 mg/g), and individual phytosterols, than the other supplement categories. Powders contained significantly higher (p < 0.05) concentrations of total fatty acids than tinctures, which contain negligible amounts of fatty acids (46.3 mg/g) and phytosterols (0.10 mg/g). Our findings suggest that liquid saw palmetto supplements may be the best choice for individuals who want to take a saw palmetto supplement with the highest concentrations of both fatty acids and phytosterols. PMID:24067389

  10. Development of Novel Atomization System Based on SAW Streaming

    NASA Astrophysics Data System (ADS)

    Chono, Katsumi; Shimizu, Norifumi; Matsui, Yoshikazu; Kondoh, Jun; Shiokawa, Showko

    2004-05-01

    In this paper, we describe a novel atomization system using surface acoustic wave (SAW) devices. The SAW radiates its energy into a liquid, if the liquid is loaded on the SAW propagating surface. The various liquid motions, such as vibration, flow and droplet formation, due to interaction between SAW and liquid are called SAW streaming. The liquid dynamics depends on the SAW input power. First, the relationships between input voltage to the SAW device and water dynamics are observed. For atomization, an input voltage larger than 30 VP-P is required. Second, a stable method of generating a mist is discussed. The thin liquid layer plays an important role in continuous mist generation. The fundamental properties, such as the angle and height of mist, are measured using a filter paper to keep a thin liquid layer on the surface. We also demonstrate the control of mist direction with an electrostatic field. Based on these fundamental experiments, a practical atomization system is designed and performed.

  11. Predictive force model for haptic feedback in bone sawing.

    PubMed

    James, Thomas P; Pearlman, John J; Saigal, Anil

    2013-11-01

    Bone sawing simulators with force feedback represent a cost effective means of training orthopedic surgeons in various surgical procedures, such as total knee arthroplasty. To develop a machine with accurate haptic feedback, giving a sensation of both cutting force and rate of material removal, algorithms are required to forecast bone sawing forces based on user input. Presently, studies on forces generated while machining bone are not representative of the high cutting speeds and low depths of cut common to the bone sawing process. The objective of this research was to quantify sawing forces in cortical bone as a function of blade speed and depth of cut. A fixture was developed to simulate linear bone sawing over a range of speeds comparable to surgical reciprocating and oscillating (sagittal) bone saws. A single saw blade tooth was isolated and used to create a slotted cut in bovine cortical bone. Over a range in linear sawing speed from 1700 to 7000 mm/s, a t-test (?=0.05) revealed there was no statistically significant effect of blade speed on either cutting or thrust force. However, an increase in depth of cut from 2 to 10 ?m resulted in a 30% increase in thrust force, while cutting force remained constant. The increase in thrust force with depth of cut was relatively linear, R(2)=0.80. Using a two factor, two level design of experiments approach, regression equations were developed to relate sawing forces to changes in blade speed and depth of cut. These equations can be used to predict forces in a haptic feedback model. PMID:23806417

  12. Analyzing the installation angle error of a SAW torque sensor

    NASA Astrophysics Data System (ADS)

    Fan, Yanping; Ji, Xiaojun; Cai, Ping

    2014-09-01

    When a torque is applied to a shaft, normal strain oriented at 45 direction to the shaft axis is at its maximum, which requires two one-port SAW resonators to be bonded to the shaft at 45 to the shaft axis. In order to make the SAW torque sensitivity high enough, the installation angle error of two SAW resonators must be confined within 5 according to our design requirement. However, there are few studies devoted to the installation angle analysis of a SAW torque sensor presently and the angle error was usually obtained by a manual method. Hence, we propose an approximation method to analyze the angle error. First, according to the sensitive mechanism of the SAW device to torque, the SAW torque sensitivity is deduced based on the linear piezoelectric constitutive equation and the perturbation theory. Then, when a torque is applied to the tested shaft, the stress condition of two SAW resonators mounted with an angle deviating from 45 to the shaft axis, is analyzed. The angle error is obtained by means of the torque sensitivities of two orthogonal SAW resonators. Finally, the torque measurement system is constructed and the loading and unloading experiments are performed twice. The torque sensitivities of two SAW resonators are obtained by applying average and least square method to the experimental results. Based on the derived angle error estimation function, the angle error is estimated about 3.447, which is close to the actual angle error 2.915. The difference between the estimated angle and the actual angle is discussed. The validity of the proposed angle error analysis method is testified to by the experimental results.

  13. [A reciprocating saw for micro-surgery (author's transl)].

    PubMed

    Feldmann, H

    1977-09-01

    A reciprocating saw for osteoplastic microsurgery of the ear is presented. An electromagnetic oscillator of a common electric razor, used as motor, drives the saw with 100 oscillations per second. The amplitude of the vibrations can be adjusted by a special device within the range of 0.5 to 3 mm. The saw blades are 0.2 mm thick and not set. They perform very smooth straight cuts of 0.2 to 0.3 mm width and can easily be applied in the narrow operative field of the middle ear. PMID:143575

  14. Multi-electrodes in SAW with square wave ac power

    SciTech Connect

    Bunker, T.A.

    1982-07-01

    Examines the feasibility of using AC square wave power for multi-electrode submerged arc welding (SAW) by arranging 2 power sources for weld test using two-electrode submerged arc welding. Presents figures showing phase relationship between lead arc current and trail arc current for Scott connected multi-electrode SAW, and arc deflection vs. electrical degrees. Suggests that Scott connection is preferred because it balances the primary line draw. Concludes that the multielectrode submerged arc process with constant potential square wave power increases travel speed and deposition rates which can be added to the economies obtained from a narrow groove joint configuration and the SAW process.

  15. High-reliability SAW bandpass filters for space applications.

    PubMed

    Hickernell, F S

    1988-01-01

    High-reliability surface-acoustic-wave (SAW) bandpass filters have been developed for use in transponders for more than 25 earth-orbital and deep-space satellite programs. SAW filters have been incorporated in several NASA standard TTandC transponders and NASA standard tracking and data relay satellite system (TDRSS) user transponders. The author gives examples of the electrical performance, summarizes the manufacturing processes, and discusses qualification testing for these SAW devices. He identifies reliability problems encountered and their solutions. PMID:18290200

  16. ISS Asset Tracking Using SAW RFID Technology

    NASA Technical Reports Server (NTRS)

    Schellhase, Amy; Powers, Annie

    2004-01-01

    A team at the NASA Johnson Space Center (JSC) is undergoing final preparations to test Surface Acoustic Wave (SAW) Radio Frequency Identification (RFID) technology to track assets aboard the International Space Station (ISS). Currently, almost 10,000 U.S. items onboard the ISS are tracked within a database maintained by both the JSC ground teams and crew onboard the ISS. This barcode-based inventory management system has successfully tracked the location of 97% of the items onboard, but its accuracy is dependant on the crew to report hardware movements, taking valuable time away from science and other activities. With the addition of future modules, the volume of inventory to be tracked is expected to increase significantly. The first test of RFID technology on ISS, which will be conducted by the Expedition 16 crew later this year, will evaluate the ability of RFID technology to track consumable items. These consumables, which include office supplies and clothing, are regularly supplied to ISS and can be tagged on the ground. Automation will eliminate line-of-sight auditing requirements, directly saving crew time. This first step in automating an inventory tracking system will pave the way for future uses of RFID for inventory tracking in space. Not only are there immediate benefits for ISS applications, it is a crucial step to ensure efficient logistics support for future vehicles and exploration missions where resupplies are not readily available. Following a successful initial test, the team plans to execute additional tests for new technology, expanded operations concepts, and increased automation.

  17. Imprinted laminate wafer-level packaging for SAW ID-tags and SAW delay line sensors.

    PubMed

    Kuypers, Jan H; Tanaka, Shuji; Esashi, Masayoshi

    2011-02-01

    We have developed a wafer-level packaging solution for surface acoustic wave devices using imprinted dry film resist (DFR). The packaging process involves the preparation of an imprinted dry film resist that is aligned and laminated to the device wafer and requires one additional lithography step to define the package outline. Two commercial dry film solutions, SU-8 and TMMF, have been evaluated. Compared with traditional ceramic packages, no detectable RF parasitics are introduced by this packaging process. At the same time, the miniature package dimensions allow for wafer-level probing. The packaging process has the great advantage that the cavity formation does not require any sacrificial layer and no liquids, and therefore prevents contamination or stiction of the packaged device. This non-hermetic packaging process is ideal for passive antenna modules using polymer technology for low-cost SAW identification (ID)-tags or lidding in low-temperature cofired ceramic (LTCC) antenna substrates for high-performance wireless sensors. This technique is also applicable to SAW filters and duplexers for module integration in cellular phones using flip-chip mounting and hermetic overcoating. PMID:21342826

  18. DNA Barcode Authentication of Saw Palmetto Herbal Dietary Supplements

    PubMed Central

    Little, Damon P.; Jeanson, Marc L.

    2013-01-01

    Herbal dietary supplements made from saw palmetto (Serenoa repens; Arecaceae) fruit are commonly consumed to ameliorate benign prostate hyperplasia. A novel DNA minibarcode assay to accurately identify [specificity = 1.00 (95% confidence interval = 0.741.00); sensitivity = 1.00 (95% confidence interval = 0.661.00); n = 31] saw palmetto dietary supplements was designed from a DNA barcode reference library created for this purpose. The minibarcodes were used to estimate the frequency of mislabeled saw palmetto herbal dietary supplements on the market in the United States of America. Of the 37 supplements examined, amplifiable DNA could be extracted from 34 (92%). Minibarcode analysis of these supplements demonstrated that 29 (85%) contain saw palmetto and that 2 (6%) supplements contain related species that cannot be legally sold as herbal dietary supplements in the United States of America. The identity of 3 (9%) supplements could not be conclusively determined. PMID:24343362

  19. 5. View of north elevation, including saw dust collector and ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. View of north elevation, including saw dust collector and brick addition, looking south east. - General Dynamics Corporation Shipyard, Joiner & Sheet Metal Shops, 97 East Howard Street, Quincy, Norfolk County, MA

  20. Anti-slipping system improves wire saw performance

    NASA Technical Reports Server (NTRS)

    Gallo, E. A.

    1971-01-01

    System prevents wire saw slippage by providing sufficient friction to turn idler spools even when turns of wire on spools do not provide sufficient friction. Low cost system is easily applied to existing equipment.

  1. 12. Interior view showing main section, mezzanine and saw tooth ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. Interior view showing main section, mezzanine and saw tooth truss roof with skylight, looking west. - College Heights Lemon Packing House, 519-532 West First Street, Claremont, Los Angeles County, CA

  2. 19. William E. Barrett, Photographer, August 1975. LOWER BAND SAW ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    19. William E. Barrett, Photographer, August 1975. LOWER BAND SAW PULLEYS OF RIGHT-HAND MILL. DRIVE PULLEY IN BELOW TENSION PULLEY. - Meadow River Lumber Company, Highway 60, Rainelle, Greenbrier County, WV

  3. 21. William E. Barrett, Photographer, August 1975. EDGER SAWS FOR ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    21. William E. Barrett, Photographer, August 1975. EDGER SAWS FOR RIPPING BOARD TO VARIOUS WIDTHS. BLADES VISIBLE BEHIND ROLLERS. - Meadow River Lumber Company, Highway 60, Rainelle, Greenbrier County, WV

  4. See-saw nystagmus and brainstem infarction: MRI findings

    NASA Technical Reports Server (NTRS)

    Kanter, D. S.; Ruff, R. L.; Leigh, R. J.; Modic, M.

    1987-01-01

    A patient with see-saw nystagmus had a lesion localized by Magnetic Resonance Imaging (MRI) to the paramedian ventral midbrain with involvement of the right interstitial nucleus of Cajal. This the first MRI study of see-saw nystagmus associated with a presumed brainstem vascular event. Our findings support animal and human studies suggesting that dysfunction of the interstitial nucleus of Cajal or its connections is central in this disorder.

  5. Effect of critical dimension variation on SAW correlator energy.

    SciTech Connect

    Skinner, Jack L.

    2005-04-01

    The effect of critical dimension (CD) variation and metallization ratio on the efficiency of energy conversion of a surface acoustic wave (SAW) correlator is examined. We find that a 10% variation in the width of finger electrodes predicts only a 1% decrease in the efficiency of energy conversion. Furthermore, our model predicts that a metallization ratio of 0.74 represents an optimum value for energy extraction from the SAW by the interdigitated transducer (IDT).

  6. Effect of critical dimension variation on SAW correlator energy.

    PubMed

    Skinner, J L; Cardinale, G F; Talin, A A; Brocato, R W

    2006-02-01

    The effect of critical dimension (CD) variation and metallization ratio on the efficiency of energy conversion of a surface acoustic wave (SAW) correlator is examined. We find that a 10% variation in the width of finger electrodes predicts only a 1% decrease in the efficiency of energy conversion. Furthermore, our model predicts that a metallization ratio of 0.74 represents an optimum value for energy extraction from the SAW by the interdigitated transducer (IDT). PMID:16529126

  7. Notes on SAW Tag Interrogation Techniques

    NASA Technical Reports Server (NTRS)

    Barton, Richard J.

    2010-01-01

    We consider the problem of interrogating a single SAW RFID tag with a known ID and known range in the presence of multiple interfering tags under the following assumptions: (1) The RF propagation environment is well approximated as a simple delay channel with geometric power-decay constant alpha >/= 2. (2) The interfering tag IDs are unknown but well approximated as independent, identically distributed random samples from a probability distribution of tag ID waveforms with known second-order properties, and the tag of interest is drawn independently from the same distribution. (3) The ranges of the interfering tags are unknown but well approximated as independent, identically distributed realizations of a random variable rho with a known probability distribution f(sub rho) , and the tag ranges are independent of the tag ID waveforms. In particular, we model the tag waveforms as random impulse responses from a wide-sense-stationary, uncorrelated-scattering (WSSUS) fading channel with known bandwidth and scattering function. A brief discussion of the properties of such channels and the notation used to describe them in this document is given in the Appendix. Under these assumptions, we derive the expression for the output signal-to-noise ratio (SNR) for an arbitrary combination of transmitted interrogation signal and linear receiver filter. Based on this expression, we derive the optimal interrogator configuration (i.e., transmitted signal/receiver filter combination) in the two extreme noise/interference regimes, i.e., noise-limited and interference-limited, under the additional assumption that the coherence bandwidth of the tags is much smaller than the total tag bandwidth. Finally, we evaluate the performance of both optimal interrogators over a broad range of operating scenarios using both numerical simulation based on the assumed model and Monte Carlo simulation based on a small sample of measured tag waveforms. The performance evaluation results not only provide guidelines for proper interrogator design, but also provide some insight on the validity of the assumed signal model. It should be noted that the assumption that the impulse response of the tag of interest is known precisely implies that the temperature and range of the tag are also known precisely, which is generally not the case in practice. However, analyzing interrogator performance under this simplifying assumption is much more straightforward and still provides a great deal of insight into the nature of the problem.

  8. Diamond Wire Saw for Precision Machining of Laser Target Components

    SciTech Connect

    Bono, M J; Bennett, D W

    2005-08-08

    The fabrication of precision laser targets requires a wide variety of specialized mesoscale manufacturing techniques. The diamond wire saw developed in this study provides the capability to precisely section meso-scale workpieces mounted on the assembly stations used by the Target Fabrication Group. This new capability greatly simplifies the fabrication of many types of targets and reduces the time and cost required to build the targets. A variety of materials are used to fabricate targets, including metals, plastics with custom designed chemical formulas, and aerogels of various densities. The materials are usually provided in the form of small pieces or cast rods that must be machined to the required shape. Many of these materials, such as metals and some plastics, can be trimmed using a parting tool on a diamond turning machine. However, other materials, such as aerogels and brittle materials, cannot be adequately cut with a parting tool. In addition, the geometry of the parts often requires that the workpieces be held in a special assembly station, which excludes the use of a parting tool. In the past, these materials were sectioned using a small, handheld coping saw that used a diamond-impregnated wire as a blade. This miniature coping saw was effective, but it required several hours to cut through certain materials. Furthermore, the saw was guided by hand and often caused significant damage to fragile aerogels. To solve these problems, the diamond wire saw shown in Figure 1 was developed. The diamond wire saw is designed to machine through materials that are mounted in the Target Fabrication Group's benchtop assembly stations. These assembly stations are the primary means of aligning and assembling target components, and there is often a need to machine materials while they are mounted in the assembly stations. Unfortunately, commercially available saws are designed for very different applications and are far too large to be used with the assembly stations. Therefore, a custom diamond wire saw was designed and constructed. The diamond wire saw cuts through workpieces using a continuous loop of diamond-impregnated wire of length 840 mm. The wire loop runs around several idler pulleys and is driven by a simple geared DC motor that rotates at 17 rpm. The linear speed of the wire is 107 inches/minute. The saw is oriented at an angle of 20{sup o} from horizontal, so the operator can view the wire through the cutout at the front end of the saw. When looking through a microscope or camera with a horizontal line of sight, the operator can clearly see the wire as it cuts through the workpiece, as shown in the right side of Figure 1. The saw is mounted on a two-axis stage that allows the operator to align the wire with the workpiece. To cut through the workpiece, the operator drives the wire through the workpiece by turning the feed micrometer. An image of the interior of the diamond wire saw appears in Figure 2. This picture was taken after removing the protective cover plate from the saw.

  9. A DETAILED SAFETY ASSESSMENT OF A SAW PALMETTO EXTRACT

    PubMed Central

    Avins, Andrew L.; Bent, Stephen; Staccone, Suzanne; Badua, Evelyn; Padula, Amy; Goldberg, Harley; Neuhaus, John; Hudes, Esther; Shinohara, Katusto; Kane, Christopher

    2008-01-01

    Background Saw palmetto is commonly used by men for lower urinary tract symptoms. Despite its widespread use, very little is known about the potential toxicity of this dietary supplement. Methods The Saw palmetto for Treatment of Enlarged Prostates (STEP) study was a randomized clinical trial performed among 225 men with moderate-to-severe symptoms of benign prostatic hyperplasia, comparing a standardized extract of the saw palmetto berry (160mg twice daily) with a placebo over a one-year period. As part of this study, detailed data were collected on serious and non-serious adverse events, sexual functioning, and laboratory tests of blood and urine. Between-group differences were assessed with mixed-effects regression models. Results There were no significant differences observed between the saw palmetto and placebo-allocated participants in the risk of suffering at least one serious adverse event (5.4% vs. 9.7%, respectively; p = 0.31) or non-serious symptomatic adverse event (34.8% vs. 30.1%; p = 0.48). There were few significant between-group differences in sexual functioning or for most laboratory analyses, with only small differences observed in changes over time in total bilirubin (p = 0.001), potassium (p = 0.03), and the incidence of glycosuria (0% in the saw palmetto group vs. 3.7% in the placebo group, p = 0.05). Conclusions Despite careful assessment, no evidence for serious toxicity of saw palmetto was observed in this clinical trial. Given the sample size and length of this study, however, these data do not rule out potential rare adverse effects associated with the use of saw palmetto. PMID:18534327

  10. Tip stabilizer for a chain saw. Final report

    SciTech Connect

    Morabit, V.D.

    1993-09-10

    Prior to receiving the grant, Utilitip was faced with an idea that truly worked, however only a very limited line of component parts would fit various types of chain saws on the market. It also suffered from a severe problem when engaged in the ground of soil penetrating the saw chain area, thus eliminating one of the major benefits of keeping the chain sharp. Consequently, the grant funding was directed towards extending the tooling capabilities to produce parts for a much wider variety of chain saws that are on the market, and further by developing an effective flexible soil shield to prevent abrasive soil entry into the saw chain. Utilitip was able to complete a full set of design for a wide variety of large and small chain saws. This incorporated a design and fabrication of a small Utilitip, as well as a small anti-kickback device. In addition, tooling was also further developed for the large Utilitip and the large anti-kickback device. Accordingly, multiple tools are available for all combinations, as well as back-up provisions. Utilitip, Inc. invented a special, flexible attachment to be glued and/or molded to the tip guard. The soil shield prevents abrasive soil from coming into the chain area. In addition, it allows a flexible arrangement to allow the chain saw to be released from brush without binding. Otherwise, a larger, rigid soil shield would hold or restrict the saw in heavy brush. The rubber shield will flex out of the say and reduce, if not eliminate, this harmful binding.

  11. Efficient transport of droplet sandwiched between saw-tooth plates.

    PubMed

    Wang, Liya; Wu, Hengan; Wang, Fengchao

    2016-01-15

    The transport of droplet sandwiched between smooth and saw-tooth plates was investigated using molecular dynamics method. The repeated opening and closing of the plates result in sequential stretching and squeezing of the droplet, which provide the driving force. The asymmetrical saw tooth obstructs the backward motion of the droplet, and gives rise to a net forward displacement of the droplet in every opening and closing cycle. This unidirectional motion facilitates the efficient droplet transport, which is referred to as the ratchet-like effect in this work. Our simulations also reveal that the influence of the surface wettability on the droplet transport is different for saw-tooth and smooth plates. Droplet transport efficiency exhibits monotonic decrease with the increase of the solid-liquid interactions for saw-tooth plates. While for smooth plates, unidirectional droplet movement was only observed for certain solid-liquid interactions. Taken together these simulation results and theoretical analysis, we demonstrate that hydrophobic saw-tooth plates can improve the transport efficiency significantly. These findings not only enhance our understanding of the droplet transport from atomistic scale, but also are beneficial to practical applications in designing of micro- and nano-fluidic systems. PMID:26473277

  12. Study of the acoustoelectric effect for SAW sensors.

    PubMed

    Fisher, Brian H; Malocha, Donald C

    2010-03-01

    Research has recently begun on the use of ultrathin films and nanoclusters as mechanisms for sensing of gases, liquids, etc., because the basic material parameters may change because of film morphology. As films of various materials are applied to the surface of SAW devices for sensors, the conductivity of the films may have a strong acoustoelectric effect, whether desired or not. The purpose of this paper is to reexamine the theory and predictions of the acoustoelectric effect for SAW interactions with thin conducting or semi-conducting films. The paper will summarize the theory and predict the effects of thin film conductivity on SAW velocity and propagation loss versus frequency and substrate material. The theory predicts regions of conductivity which result in extremely high propagation loss, and which also correspond to the mid-point between the open and short-circuit velocities. As an example of the verification and possible usefulness of the acoustoelectric effect, recent experimental results of palladium (Pd) thin films on a YZ LiNbO3 SAW delay line have shown large changes in propagation loss, depending on the Pd film thickness, exposure to hydrogen gas, or both. By proper design, a sensitive hydrogen leak detector SAW sensor can be designed. PMID:20211790

  13. High-Temperature SAW Wireless Strain Sensor with Langasite

    PubMed Central

    Shu, Lin; Peng, Bin; Yang, Zhengbing; Wang, Rui; Deng, Senyang; Liu, Xingzhao

    2015-01-01

    Two Surface acoustic wave (SAW) resonators were fabricated on langasite substrates with Euler angle of (0°, 138.5°, 117°) and (0°, 138.5°, 27°). A dipole antenna was bonded to the prepared SAW resonator to form a wireless sensor. The characteristics of the SAW sensors were measured by wireless frequency domain interrogation methods from 20 °C to 600 °C. Different temperature behaviors of the sensors were observed. Strain sensing was achieved using a cantilever configuration. The sensors were measured under applied strain from 20 °C to 500 °C. The shift of the resonance frequency contributed merely by strain is extracted from the combined effects of temperature and strain. Both the strain factors of the two SAW sensors increase with rising ambient temperature, and the SAW sensor deposited on (0°, 138.5°, 117°) cut is more sensitive to applied strain. The measurement errors of the two sensors are also discussed. The relative errors of the two sensors are between 0.63% and 2.09%. Even at 500 °C, the hysteresis errors of the two sensors are less than 5%. PMID:26569255

  14. High-Temperature SAW Wireless Strain Sensor with Langasite.

    PubMed

    Shu, Lin; Peng, Bin; Yang, Zhengbing; Wang, Rui; Deng, Senyang; Liu, Xingzhao

    2015-01-01

    Two Surface acoustic wave (SAW) resonators were fabricated on langasite substrates with Euler angle of (0°, 138.5°, 117°) and (0°, 138.5°, 27°). A dipole antenna was bonded to the prepared SAW resonator to form a wireless sensor. The characteristics of the SAW sensors were measured by wireless frequency domain interrogation methods from 20 °C to 600 °C. Different temperature behaviors of the sensors were observed. Strain sensing was achieved using a cantilever configuration. The sensors were measured under applied strain from 20 °C to 500 °C. The shift of the resonance frequency contributed merely by strain is extracted from the combined effects of temperature and strain. Both the strain factors of the two SAW sensors increase with rising ambient temperature, and the SAW sensor deposited on (0°, 138.5°, 117°) cut is more sensitive to applied strain. The measurement errors of the two sensors are also discussed. The relative errors of the two sensors are between 0.63% and 2.09%. Even at 500 °C, the hysteresis errors of the two sensors are less than 5%. PMID:26569255

  15. Effect of lubricant environment on saw damage in silicon wafers

    NASA Technical Reports Server (NTRS)

    Kuan, T. S.; Shih, K. K.; Vanvechten, J. A.; Westdorp, W. A.

    1982-01-01

    The chemomechanical effect of lubricant environments on the inner diameter (ID) sawing induced surface damage in Si wafers was tested for four different lubricants: water, dielectric oil, and two commercial cutting solutions. The effects of applying different potential on Si crystals during the sawing were also tested. It is indicated that the number and depth of surface damage are sensitive to the chemical nature of the saw lubricant. It is determined that the lubricants that are good catalysts for breaking Si bonds can dampen the out of plane blade vibration more effectively and produce less surface damage. Correlations between the applied potential and the depth of damage in the dielectric oil and one of the commercial cutting solutions and possible mechanisms involved are discussed.

  16. A high sensitivity nanomaterial based SAW humidity sensor

    NASA Astrophysics Data System (ADS)

    Wu, Tsung-Tsong; Chen, Yung-Yu; Chou, Tai-Hsu

    2008-04-01

    In this paper, a highly sensitive humidity sensor is reported. The humidity sensor is configured by a 128YX-LiNbO3 based surface acoustic wave (SAW) resonator whose operating frequency is at 145 MHz. A dual delay line configuration is realized to eliminate external temperature fluctuations. Moreover, for nanostructured materials possessing high surface-to-volume ratio, large penetration depth and fast charge diffusion rate, camphor sulfonic acid doped polyaniline (PANI) nanofibres are synthesized by the interfacial polymerization method and further deposited on the SAW resonator as selective coating to enhance sensitivity. The humidity sensor is used to measure various relative humidities in the range 5-90% at room temperature. Results show that the PANI nanofibre based SAW humidity sensor exhibits excellent sensitivity and short-term repeatability.

  17. An Unorthodox Alternative for Righthanded Neutrinos: Lefthanded See--Saw

    NASA Astrophysics Data System (ADS)

    Krolikowski, Wojciech

    2000-03-01

    A new lefthanded see--saw mechanism is constructed, implying both the smallness of active-neutrino masses and decoupling of heavy passive neutrinos, similarly to the situation in the case of conventional see--saw. But now, in place of the conventional righthanded neutrinos, the lefthanded sterile neutrinos play the role of heavy passive neutrinos, the righthanded neutrinos and righthanded sterile neutrinos being absent. Here, the lefthanded sterile neutrinos are different from charge conjugates of conventional righthanded neutrinos because their lepton numbers differ. In this case, the neutrino mass term is necessarily of pure Majorana type.

  18. A surface acoustic wave /SAW/ charge transfer imager

    NASA Technical Reports Server (NTRS)

    Papanicolauo, N. A.; Lin, H. C.

    1981-01-01

    An 80 MHz, 2-microsecond surface acoustic wave charge transfer device (SAW-CTD) has been fabricated in which surface acoustic waves are used to create traveling longitudinal electric fields in the silicon substrate and to replace the multiphase clocks of charge coupled devices. The traveling electric fields create potential wells which will carry along charges that may be stored in the wells; the charges may be injected into the wells by light. An optical application is proposed where the SAW-CTD structure is used in place of a conventional interline transfer design.

  19. Development of SH-SAW sensors for underwater measurement.

    PubMed

    Kwon, Y; Roh, Y

    2004-04-01

    We developed SH (shear horizontal) surface acoustic wave (SAW) sensors to detect protein molecules in liquid solutions applying a particular antibody thin film on the delay line of transverse SAW devices. The antibody investigated was human-immuno-globulin G (HigG) to hold the antigens (anti-HigG) in the protein solution to be measured. The sensor showed stable response to the mass loading effects of the anti-HigG molecules with the sensitivity up to 10.8 ng/ml/Hz. PMID:15047320

  20. Robust Design of SAW Gas Sensors by Taguchi Dynamic Method.

    PubMed

    Tsai, Hsun-Heng; Wu, Der Ho; Chiang, Ting-Lung; Chen, Hsin Hua

    2009-01-01

    This paper adopts Taguchi's signal-to-noise ratio analysis to optimize the dynamic characteristics of a SAW gas sensor system whose output response is linearly related to the input signal. The goal of the present dynamic characteristics study is to increase the sensitivity of the measurement system while simultaneously reducing its variability. A time- and cost-efficient finite element analysis method is utilized to investigate the effects of the deposited mass upon the resonant frequency output of the SAW biosensor. The results show that the proposed methodology not only reduces the design cost but also promotes the performance of the sensors. PMID:22573961

  1. SAW chemical sensor arrays using new thin-film materials

    SciTech Connect

    Ricco, A.J.; Xu, Chuanjing; Crooks, R.M.; Allred, R.E.

    1994-05-01

    We have used two classes of materials, self-assembled monolayers (SAMs) and plasma-grafted films (PGFs), as new chemically sensitive layers for an array of 97-MHz surface acoustic wave (SAW) delay-line-based devices. Responses of these materials to each of 14 different analytes, representing the classes of saturated alkane, aromatic hydrocarbon, chlorinated hydrocarbon, alcohol, ketone, organophosphonate, and water, have been evaluated using our six-SAW device array. Results reveal a qualitative ``chemical orthogonality`` of the films that is very promising for pattern recognition analysis.

  2. SAW convolvers using the transverse-horizontal bilinear field

    NASA Astrophysics Data System (ADS)

    Monks, T.; Paige, E. G. S.; Woods, R. C.

    1983-06-01

    The surface-acoustic-wave (SAW) convolver provides a means of achieving high time-bandwidth, programmable signal processing. The operation of most SAW convolver designs has been based on the detection of an electric-polarization field normal to the crystal surface. The field arises from the mixing of two counter-propagating surface-acoustic waves. The present investigation is concerned with a new type of convolver which is based on the detection of the bilinear electric polarization parallel to the crystal surface and to the input wave-front. The new device is called a transverse-horizontal convolver (THC). A new electrode arrangement is needed to detect the polarization.

  3. 28. MODIFIED CHAIN SAW FOR CUTTING ROCK CORES; BRUNTON COMPASS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    28. MODIFIED CHAIN SAW FOR CUTTING ROCK CORES; BRUNTON COMPASS STAND FOR DETERMINING CORE'S FIELD ORIENTATION; INSECTICIDE DISPENSER MODIFIED TO LUBRICATE CORE DRILLING PROCESS. - U.S. Geological Survey, Rock Magnetics Laboratory, 345 Middlefield Road, Menlo Park, San Mateo County, CA

  4. Hepatotoxicity potential of saw palmetto (Serenoa repens) in rats.

    PubMed

    Singh, Y N; Devkota, A K; Sneeden, D C; Singh, K K; Halaweish, F

    2007-02-01

    Saw palmetto (Serenoa repens L.) is an herbal drug used to treat symptoms of benign prostatic hyperplasia (BPH) and lower urinary tract symptoms (LUTS). There has been a report that a preparation containing this herb has caused cholestatic hepatitis in one person and some indications exist that it may have the potential to produce liver toxicity. The purpose of this study was to evaluate the effect of saw palmetto on rat liver function by measuring its effects on several enzymes and formation of malondialdehyde (MDA), a byproduct of lipid peroxidation. A significant increase in these parameters is considered an indication of liver toxicity. Thirty-six rats were divided into 6 groups of 6 animals each. They were treated for 2 or 4 weeks with a placebo or saw palmetto at doses of 9.14 or 22.86 mg/kg/body wt./day; that is, 2 x and 5 x the maximum recommended daily human dosages. After 2 or 4 weeks, the animals were sacrificed and blood was collected to prepare serum for enzyme assays, which were performed using commercially available kits. A portion of the liver was removed, and a homogenate prepared for the lipid peroxidation assay. Results showed no significant difference in animal body weight, enzyme activity, or MDA formation at either time or dosage level, as compared to controls. The data indicate that at the doses and time periods tested, saw palmetto did not produce any significant effect on the normal biological markers of liver toxicity. PMID:16854576

  5. A novel wireless and temperature-compensated SAW vibration sensor.

    PubMed

    Wang, Wen; Xue, Xufeng; Huang, Yangqing; Liu, Xinlu

    2014-01-01

    A novel wireless and passive surface acoustic wave (SAW) based temperature-compensated vibration sensor utilizing a flexible Y-cut quartz cantilever beam with a relatively substantial proof mass and two one-port resonators is developed. One resonator acts as the sensing device adjacent to the clamped end for maximum strain sensitivity, and the other one is used as the reference located on clamped end for temperature compensation for vibration sensor through the differential approach. Vibration directed to the proof mass flex the cantilever, inducing relative changes in the acoustic propagation characteristics of the SAW travelling along the sensing device, and generated output signal varies in frequency as a function of vibration.  A theoretical mode using the Rayleigh method was established to determine the optimal dimensions of the cantilever beam. Coupling of Modes (COM) model was used to extract the optimal design parameters of the SAW devices prior to fabrication. The performance of the developed SAW sensor attached to an antenna towards applied vibration was evaluated wirelessly by using the precise vibration table, programmable incubator chamber, and reader unit.  High vibration sensitivity of ~10.4 kHz/g, good temperature stability, and excellent linearity were observed in the wireless measurements. PMID:25372617

  6. Brickconstructed saw toothprofile fire wall between the Cannery and original ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Brick-constructed saw tooth-profile fire wall between the Cannery and original Warehouse (demolished), note the steel trusses remaining on the wall from the Warehouse roof, view facing north northeast - Kahului Cannery, Plant No. 28, Cannery Building and Dryer House/Feed Storage Building, 120 Kane Street, Kahului, Maui County, HI

  7. Overview of Cannery Building, note the saw tooth monitors with ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Overview of Cannery Building, note the saw tooth monitors with glazing and with corrugated fiberglass and screens, view facing north - Kahului Cannery, Plant No. 28, Cannery Building and Dryer House/Feed Storage Building, 120 Kane Street, Kahului, Maui County, HI

  8. Surface Acoustic Wave (SAW) Resonators for Monitoring Conditioning Film Formation

    PubMed Central

    Hohmann, Siegfried; Kögel, Svea; Brunner, Yvonne; Schmieg, Barbara; Ewald, Christina; Kirschhöfer, Frank; Brenner-Weiß, Gerald; Länge, Kerstin

    2015-01-01

    We propose surface acoustic wave (SAW) resonators as a complementary tool for conditioning film monitoring. Conditioning films are formed by adsorption of inorganic and organic substances on a substrate the moment this substrate comes into contact with a liquid phase. In the case of implant insertion, for instance, initial protein adsorption is required to start wound healing, but it will also trigger immune reactions leading to inflammatory responses. The control of the initial protein adsorption would allow to promote the healing process and to suppress adverse immune reactions. Methods to investigate these adsorption processes are available, but it remains difficult to translate measurement results into actual protein binding events. Biosensor transducers allow user-friendly investigation of protein adsorption on different surfaces. The combination of several transduction principles leads to complementary results, allowing a more comprehensive characterization of the adsorbing layer. We introduce SAW resonators as a novel complementary tool for time-resolved conditioning film monitoring. SAW resonators were coated with polymers. The adsorption of the plasma proteins human serum albumin (HSA) and fibrinogen onto the polymer-coated surfaces were monitored. Frequency results were compared with quartz crystal microbalance (QCM) sensor measurements, which confirmed the suitability of the SAW resonators for this application. PMID:26007735

  9. Fiber properties of saw and roller ginned naturally colored cottons

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Naturally colored cottons have economic and environmental appeal because they do not require dyeing, but their fibers are not as long as white cottons. To determine the best ginning process two Upland (/G. hirsutim/) colors were roller and saw ginned following a complete block experimental design. ...

  10. Suppressing buzz-saw noise in jet engines

    NASA Technical Reports Server (NTRS)

    Maestrello, L.

    1980-01-01

    Buzz-saw noise, most annoying noise component generated by turbofan engines, can be suppresses by installing porous surface on duct wall directly above engine fan-blade tip. Porous surface and its housing would reduce shock-wave reflection from wall and thus suppress noise.

  11. Surface Acoustic Wave (SAW) Resonators for Monitoring Conditioning Film Formation.

    PubMed

    Hohmann, Siegfried; Kgel, Svea; Brunner, Yvonne; Schmieg, Barbara; Ewald, Christina; Kirschhfer, Frank; Brenner-Wei, Gerald; Lnge, Kerstin

    2015-01-01

    We propose surface acoustic wave (SAW) resonators as a complementary tool for conditioning film monitoring. Conditioning films are formed by adsorption of inorganic and organic substances on a substrate the moment this substrate comes into contact with a liquid phase. In the case of implant insertion, for instance, initial protein adsorption is required to start wound healing, but it will also trigger immune reactions leading to inflammatory responses. The control of the initial protein adsorption would allow to promote the healing process and to suppress adverse immune reactions. Methods to investigate these adsorption processes are available, but it remains difficult to translate measurement results into actual protein binding events. Biosensor transducers allow user-friendly investigation of protein adsorption on different surfaces. The combination of several transduction principles leads to complementary results, allowing a more comprehensive characterization of the adsorbing layer. We introduce SAW resonators as a novel complementary tool for time-resolved conditioning film monitoring. SAW resonators were coated with polymers. The adsorption of the plasma proteins human serum albumin (HSA) and fibrinogen onto the polymer-coated surfaces were monitored. Frequency results were compared with quartz crystal microbalance (QCM) sensor measurements, which confirmed the suitability of the SAW resonators for this application. PMID:26007735

  12. Measurements results of SAW humidity sensor with nafion layer

    NASA Astrophysics Data System (ADS)

    Kawalec, A.; Jasek, K.; Pasternak, M.

    2008-02-01

    The results of measurements of surface acoustic wave (SAW) humidity sensor with nafion layer are described in the paper. The sensitivity, response time as well as hysteresis for different temperatures have been investigated. The sensor sensitivity, linearity and hystersis are discussd. The results show that such sensor may be suitable for accurate humidity measurements in dry or hot enough environment.

  13. A Novel Wireless and Temperature-Compensated SAW Vibration Sensor

    PubMed Central

    Wang, Wen; Xue, Xufeng; Huang, Yangqing; Liu, Xinlu

    2014-01-01

    A novel wireless and passive surface acoustic wave (SAW) based temperature-compensated vibration sensor utilizing a flexible Y-cut quartz cantilever beam with a relatively substantial proof mass and two one-port resonators is developed. One resonator acts as the sensing device adjacent to the clamped end for maximum strain sensitivity, and the other one is used as the reference located on clamped end for temperature compensation for vibration sensor through the differential approach. Vibration directed to the proof mass flex the cantilever, inducing relative changes in the acoustic propagation characteristics of the SAW travelling along the sensing device, and generated output signal varies in frequency as a function of vibration. A theoretical mode using the Rayleigh method was established to determine the optimal dimensions of the cantilever beam. Coupling of Modes (COM) model was used to extract the optimal design parameters of the SAW devices prior to fabrication. The performance of the developed SAW sensor attached to an antenna towards applied vibration was evaluated wirelessly by using the precise vibration table, programmable incubator chamber, and reader unit. High vibration sensitivity of ?10.4 kHz/g, good temperature stability, and excellent linearity were observed in the wireless measurements. PMID:25372617

  14. Development of a SAW duplexer with one-chip isolation circuits.

    PubMed

    Roh, Yongrae; Lee, Seunghee

    2004-04-01

    We propose new structures of one-chip type SAW duplexers where Tx and Rx SAW ladder filters as well as isolation networks are fabricated together on a single 36 degrees LiTaO(3) piezoelectric substrate. The new SAW duplexer can overcome the difficulty in fabrication of conventional SAW duplexers while providing the performance matching that of conventional duplexers. Validity of the structure is verified through numerical simulation and experiments. PMID:15047321

  15. SAW with multiple electrodes achieves high production rates

    SciTech Connect

    Tusek, J.

    1996-08-01

    Increased demands for higher productivity in the production of welded structures dictate the use of new higher-performance welding procedures. Submerged arc welding (SAW) is already one of the highest performing arc welding processes, but with certain improved variants, its performance can be increased. These variants are multiple-head welding, double electrode welding and submerged arc welding with metal powder addition. These three variations of submerged arc welding have been put into practice and are extensively treated in the welding literature. The application of welding with more than three wires in a joint contact tube is rare, however, and rarely mentioned. The purpose of this article is to show the basic characteristics and eventual applications of SAW using multiple electrodes.

  16. Passive hybrid sensing tag with flexible substrate saw device

    DOEpatents

    Skinner, Jack L.; Chu, Eric Y.; Ho, Harvey

    2012-12-25

    The integration of surface acoustic wave (SAW) filters, microfabricated transmission lines, and sensors onto polymer substrates in order to enable a passive wireless sensor platform is described herein. Incident microwave pulses on an integrated antenna are converted to an acoustic wave via a SAW filter and transmitted to an impedance based sensor, which for this work is a photodiode. Changes in the sensor state induce a corresponding change in the impedance of the sensor resulting in a reflectance profile. Data collected at a calibrated receiver is used to infer the state of the sensor. Based on this principal, light levels were passively and wirelessly demonstrated to be sensed at distances of up to about 12 feet.

  17. Covalent bound sensing layers on surface acoustic wave (SAW) biosensors.

    PubMed

    Bari, N; Rapp, M

    2001-12-01

    This paper reports on the development of immunosensors based on commercially available surface acoustic wave (SAW) devices working at 380 MHz. Approaches for coating the sensor surface with a sensing layer of receptive biomolecules are presented and discussed. It was found that the sensitivity strongly relates to the immobilization method. Additionally, the sensitivity can be influenced by the density of accessible biomolecules on the active sensing area. Usually, by most of the standard immobilization procedures, two-dimensional layers of receptive biomolecules are obtained. We present a three-dimensional layer, which provides a higher absolute amount of recognition molecules. A dextran layer is photoimmobilized to the sensor surface and the recognition molecules are covalently embedded into the dextran matrix. The feasibility of specific immunosensing is investigated using SAW sensors connected to a fluid handling system. PMID:11679278

  18. SAW devices based on novel surface wave excitations

    NASA Astrophysics Data System (ADS)

    Therrien, Joel; Dai, Lian

    2015-03-01

    Surface Acoustic Wave (SAW) devices have applications in radio frequency and microwave filtering as well as highly sensitive sensors. Current SAW design employs the use of an array of electrode pairs, referred to as Inter-Digitated Transducers (IDTs) for creating and receiving surface waves on piezoelectric substrates. The pitch of the electrode pairs along with the properties of the substrate determine the operating frequency. The number of electrode pairs determine the bandwidth of the emitted waves. We will present a novel configuration that eliminates the need for the IDTs and replaces with with a single circular electrode located inside a larger ground ring. This configuration induces drumhead modes. We will show that the resonant frequencies follow the zeros of Bessel functions of the first kind. Applications in RF filtering and mass sensing will be presented.

  19. Dual SAW sensor technique for determining mass and modulus changes.

    PubMed

    Hietala, S L; Hietala, V M; Brinker, C J

    2001-01-01

    Surface acoustic wave (SAW) sensors, which are sensitive to a variety of surface changes, have been widely used for chemical and physical sensing. The ability to control or compensate for the many surface forces has been instrumental in collecting valid data. In cases in which it is not possible to neglect certain effects, such as frequency drift with temperature, methods such as the "dual sensor" technique have been utilized. This paper describes a novel use of a dual sensor technique, using two sensor materials (quartz and GaAs) to separate out the contributions of mass and modulus of the frequency change during gas adsorption experiments. The large modulus change in the film calculated using this technique and predicted by the Gassmann equation provide a greater understanding of the challenges of SAW sensing. PMID:11367793

  20. Hydrogen-Bond Basic Siloxane Phosphonate Polymers for Surface Acoustic Wave (Saw) Sensors

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A surface acoustic wave (SAW) sensor coated with a novel hydrogen-bond basic siloxane phosphonate SAW polymer gave excellent initial response and long-term performance when tested against phenol vapor and compared with polyethyleneimine (PEI), a conventional hydrogent-bond basic SAW polymer....

  1. STUDY OF A WIRE BRUSH GRID BAR REPLACEMENT FOR SAW-TYPE LINT CLEANERS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Saw type lint cleaners are commonly used to improve the overall quality of ginned lint through the removal of non-lint material and short fibers. A standard saw type lint cleaner is made up of several components: the feed works, saws, and grid bars. Slover Manufacturing (Lamesa, TX) has designed an...

  2. On spurious bulk wave excitation in SAW grating reflectors on GaAs(001)(110)

    NASA Technical Reports Server (NTRS)

    Danicki, E.; Hunt, W. D.

    1995-01-01

    Reflection of SAW (surface acoustic waves) from groove gratings on a cubic crystal is analyzed numerically on the basis of perturbation theory. It is shown that for certain angles of incidence, the conversion of SAW into bulk waves vanishes. This reduces the SAW reflection loss from grating.

  3. BAW and SAW sensors for in-situ analysis

    NASA Technical Reports Server (NTRS)

    Bar-Cohen, Y.; Bao, X. Q.; Chang, Z.; Sherrit, S.

    2003-01-01

    In-situ analysis is a major goal in current and future NASA exploration missions. In general in-situ analysis experiments are designed to investigate chmical, biological or geological markers or properties to determine the complex history of the body being studied. In order to expand the number of applicable sensor schemes an investigation into piezoelectric bulk acoustic wave (BAW) and surface acoustic wave (SAW) resonators has been initiated.

  4. Characterization and Qualification of a Precision Diamond Saw

    SciTech Connect

    Morgenstern, H.A.

    1999-03-04

    A precision diamond saw was characterized and qualified for production using the MCCS Encryption Translator (MET) network. This characterization was performed in three steps. First the equipment was evaluated and characterized, and then a process was developed and characterized to saw cofire networks. Finally, the characterized process was qualified for production using the MET network. During the development of the low-temperature cofired ceramic (LTCC) processes needed to build the MCCS Encryption Translator (MET) network, a problem was uncovered. The laser process planned for scribing and separating was found to weaken the LTCC material by about 30%. A replacement process was needed, and precision diamond sawing was chosen. During the equipment evaluation and characterization, several parameters were investigated. These were cut depth, feed rate, spindle speed, and saw blade thickness. Once these were understood the process was then developed. Initially 24 variables were identified for the process, and eventually 12 of these variables were found to be critical. These variables were then adjusted until a process envelope was found that produced acceptable product. Finally parameters were chosen from the middle of the process envelope for production. With the production process set, the next step was to qualify it for production. Two criteria had to be met: visual acceptability and bending strength. The parts were examined under a microscope and found to be visually acceptable. Parts were then put through a four-point bend test, and the strengths recorded were equivalent to those measured in the past. With the completion of this work and the acceptable results, this process was qualified for production use.

  5. Characterization of graphene oxide nanofilms obtained by the SAW atomization

    NASA Astrophysics Data System (ADS)

    Balachova, O. V.; Balashov, S. M.; Kubota, L. T.; Timm, R. A.; Nascimento, P. H.; Pavani Filho, A.; Moshkalev, S.

    2015-03-01

    Due to its ability to absorb water molecules, graphene oxide (GO) is considered a promising material for sensitive coatings in fast surface acoustic wave (SAW) humidity sensors. In this work, we characterize GO films obtained by the SAW atomization technique. It is shown that the atomized submicroliter droplets of aqueous suspension of GO can be deposited onto the surface of Si, LiNbO3 or quartz substrates forming discrete or continuous films of nanometer thickness. The deposited films were examined using AFM and electron microscopy. We discuss the dependence of thickness and structure of the obtained GO films on the parameters of deposition: the number of atomized droplets, a volume of the initial droplet, a distance between the atomizer and the sample, etc. To evaluate the adsorption characteristics of the obtained GO films, we used them as sensitive coatings of the SAW humidity sensors. We found that the adsorption characteristics of the GO films are determined by fast adsorption on the surface of GO sheets and slow adsorption, attributed to limited penetration of water molecules between the sheets, and depend on the number of deposited layers.

  6. Orthogonal frequency coding for SAW tagging and sensors.

    PubMed

    Puccio, Derek; Malocha, Donald C; Saldanha, Nancy; Gallagher, Daniel R; Hines, Jacqueline H

    2006-02-01

    Surface acoustic wave (SAW)-based sensors can offer wireless, passive operation in numerous environments, and various device embodiments are used for retrieval of the sensed data information. Single sensor systems typically can use a single carrier frequency and a simple device embodiment because tagging is not required. In a multisensor environment, it is necessary to both identify the sensor and retrieve the sensed information. This paper presents the concept of orthogonal frequency coding (OFC) for applications to SAW sensor technology. The OFC offers all advantages inherent to spread spectrum communications, including enhanced processing gain and lower interrogation power spectral density (PSD). It is shown that the time ambiguity in the OFC compressed pulse is significantly reduced as compared with a single frequency tag having the same code length, and additional coding can be added using a pseudo-noise (PN) sequence. The OFC approach is general and should be applicable to many differing SAW sensors for temperature, pressure, liquid, gases, etc. Device embodiments are shown, and a potential transceiver is described. Measured device results are presented and compared with coupling of modes (COM) model predictions to demonstrate performance. Devices then are used in computer simulations of the proposed transceiver design, and the results of an OFC sensor system are discussed. PMID:16529112

  7. Technology towards a SAW based phononic crystal sensor

    NASA Astrophysics Data System (ADS)

    Schmidt, Marc-Peter; Oseev, Aleksandr; Lucklum, Ralf; Hirsch, Soeren

    2015-05-01

    Phononic crystals (PnC) with a specifically designed defect have been recently introduced as novel sensor platform. Those sensors feature a band gap covering the typical input span of the measurand as well as a narrow transmission peak within the band gap where the frequency of maximum transmission is governed by the measurand. This innovative approach has been applied for determination of compounds in liquids [1]. Improvement of sensitivity requires higher probing frequencies around 100 MHz and above. In this range surface acoustic wave devices (SAW) provide a promising basis for PnC based microsensors [2]. The respective feature size of the PnC SAW sensor has dimensions in the range of 100 μm and below. Whereas those dimensions are state of the art for common MEMS materials, etching of holes and cavities in piezoelectric materials having an aspect ratio diameter/depth is challenging. In this contribution we describe an improved technological process to manufacture considerably deep and uniform phononic crystal structures inside of SAW substrates.

  8. [Sawing and welding with ultrasonics. Experimental investigation to test the applicability of an apparatus for sawing and welding bone tissue with ultrasonics in orthopedics (author's transl)].

    PubMed

    Picht, U; Schumpe, G; Milachowski, K

    1977-02-01

    An experimental investigation of a procedure for sawing and welding of bone tissue with ultrasonics in the area of orthopedics was reported. The welding of bone with ultrasonic waves, bone meal and a plastic adhesive did not product satisfactory results in terms of stability and tissue reaction. The applicability of the ultrasonic saw is limited by the thickness of the bone on which the osteotomy is to be performed. We saw no advantages over against the oscillating saws which were available to us. In our opinion, an indication for the application of the ultrasonic apparatus could be the removal of inflammatory, tumerous or necrotic bone processes. PMID:842093

  9. X-ray topography analysis of acoustic wave fields in the SAW-resonator structures.

    PubMed

    Roshchupkin, Dmitry V; Roshchupkina, Helen D; Irzhak, Dmitry V

    2005-11-01

    The formation of fields of standing surface acoustic waves (SAW) in LiNbO3 and La3Ga5SiO14 (LGS) crystals was studied by high-resolution topography method on a laboratory X-ray source. The fields of standing SAW were formed using SAW-resonator structures consisting of interdigital transducer (IDT) and reflecting gratings. The SAW amplitudes and power flow angles were measured by X-ray topography, diffraction in acoustic beam was visualized, and the SAW interaction with the crystal structure defects was studied. PMID:16422421

  10. 1st Order Modeling of a SAW Delay Line using MathCAD(Registered)

    NASA Technical Reports Server (NTRS)

    Wilson, William C.; Atkinson, Gary M.

    2007-01-01

    To aid in the development of SAW sensors for Integrated Vehicle Health Monitoring applications, a first order model of a SAW Delay line has been created using MathCadA. The model implements the Impulse Response method to calculate the frequency response, impedance, and insertion loss. This paper presents the model and the results from the model for a SAW delay line design. Integrated Vehicle Health Monitoring (IVHM) of aerospace vehicles requires rugged sensors having reduced volume, mass, and power that can be used to measure a variety of phenomena. Wireless systems are preferred when retro-fitting sensors onto existing vehicles [1]. Surface Acoustic Wave (SAW) devices are capable of sensing: temperature, pressure, strain, chemical species, mass loading, acceleration, and shear stress. SAW technology is low cost, rugged, lightweight, and extremely low power. Passive wireless sensors have been developed using SAW technology. For these reasons new SAW sensors are being investigated for aerospace applications.

  11. Congenital Achiasma and See-Saw Nystagmus in VACTERL Syndrome

    PubMed Central

    Prakash, Saurabh; Dumoulin, Serge; Fischbein, Nancy; Wandell, Brian A.; Liao, Yaping Joyce

    2013-01-01

    A 29-year-old man with vertebral defects, anal atresia, cardiac defects, tracheoesophageal fistula, renal defects, and limb defects (VACTERL) presented with headache, photophobia, and worsening nystagmus. He had near-normal visual acuity and visual fields, absent stereopsis, and see-saw nystagmus. Brain MRI revealed a thin remnant of the optic chiasm but normal-sized optic nerves. Functional MRI during monocular visual stimulation demonstrated non-crossing of the visual evoked responses in the occipital cortex, confirming achiasma. These findings have not previously been reported in VACTERL. PMID:20182207

  12. Novel SH-SAW gas sensor based on graphene

    NASA Astrophysics Data System (ADS)

    Nikolaou, I.; Hallil, H.; Deligeorgis, G.; Conedera, V.; Garcia, H.; Dejous, C.; Rebire, D.

    2015-05-01

    In this article, a novel gas sensor platform has been studied. Several layers of graphene have been deposited on a SH-SAW, as a sensitive layer. Innovative methods of graphene solutions have been prepared in order to explore gas sensing applications. The real time detection measurement of the coated sensor under ethanol and humidity is presented. The adsorption of vapors leads to a frequency shift of 10.5 kHz and 22.7 kHz, at exposure of 100 ppm of ethanol and 6.22% of Relative Humidity, respectively. The experiments have been realized at room temperature; rapid response and recovery time were observed.

  13. Silicon saw-tooth refractive lens for high-energy x-rays made using a diamond saw.

    SciTech Connect

    Said, A. H.; Shastri, S. D.; X-Ray Science Division

    2010-01-01

    Silicon is a material well suited for refractive lenses operating at high X-ray energies (>50 keV), particularly if implemented in a single-crystal form to minimize small-angle scattering. A single-crystal silicon saw-tooth refractive lens, fabricated by a dicing process using a thin diamond wheel, was tested with 115 keV X-rays, giving an ideal 17 {mu}m line focus width in a long focal length, 2:1 ratio demagnification geometry, with a source-to-focus distance of 58.5 m. The fabrication is simple, using resources typically available at any synchrotron facility's optics shop.

  14. Modelling Sawing of Metal Tubes Through FEM Simulation

    NASA Astrophysics Data System (ADS)

    Bort, C. M. Giorgio; Bosetti, P.; Bruschi, S.

    2011-05-01

    The paper presents the development of a numerical model of the sawing process of AISI 304 thin tubes, which is cut through a circular blade with alternating roughing and finishing teeth. The numerical simulation environment is the three-dimensional FEM software Deform™ v.10.1. The teeth actual trajectories were determined by a blade kinematics analysis developed in Matlab™. Due to the manufacturing rolling steps and subsequent welding stage, the tube material is characterized by a gradient of properties along its thickness. Consequently, a simplified cutting test was set up and carried out in order to identify the values of relevant material parameters to be used in the numerical model. The dedicated test was the Orthogonal Tube Cutting test (OTC), which was performed on an instrumented lathe. The proposed numerical model was validated by comparing numerical results and experimental data obtained from sawing tests carried out on an industrial machine. The following outputs were compared: the cutting force, the chip thickness, and the chip contact area.

  15. Palestine Saw-scaled Vipers hunt disadvantaged avian migrants.

    PubMed

    Yosef, Reuven; Zduniak, Piotr

    2015-11-01

    The selection of an ambush-cum-foraging site and proper prey are indispensable for maintaining an adequate energy intake by sit-and-wait predators to optimize survival and future fitness. This is important for snakes, where an ambush site has suitable ambience. We studied the foraging strategy of the Palestine Saw-scaled Viper (Echis coloratus) at an avian migratory stopover site. Following initial observations, we hypothesized that vipers are able to discern the body mass of a perched bird and hunt accordingly. We implemented an experiment where vipers chose between four groups of migratory Blackcaps with different body mass. Prey choice by vipers of both age classes was not random and adults focused on Blackcaps with the lightest body mass. Juveniles displayed a variability of prey choice but selected mainly birds from the lightest categories. We concluded that Saw-scaled Vipers hunt prey based on thermal cues; juveniles practice on different prey groups prior to perfecting their foraging techniques i.e., hunting is a learned process; and that they prefer birds with the lowest body mass. The last because Blackcaps, when on migration, save energy by entering a state of deep torpor in which they sacrifice their vigilance capabilities. PMID:26319368

  16. Modelling Sawing of Metal Tubes Through FEM Simulation

    SciTech Connect

    Bort, C. M. Giorgio; Bosetti, P.; Bruschi, S.

    2011-05-04

    The paper presents the development of a numerical model of the sawing process of AISI 304 thin tubes, which is cut through a circular blade with alternating roughing and finishing teeth. The numerical simulation environment is the three-dimensional FEM software Deform v.10.1. The teeth actual trajectories were determined by a blade kinematics analysis developed in Matlab. Due to the manufacturing rolling steps and subsequent welding stage, the tube material is characterized by a gradient of properties along its thickness. Consequently, a simplified cutting test was set up and carried out in order to identify the values of relevant material parameters to be used in the numerical model. The dedicated test was the Orthogonal Tube Cutting test (OTC), which was performed on an instrumented lathe. The proposed numerical model was validated by comparing numerical results and experimental data obtained from sawing tests carried out on an industrial machine. The following outputs were compared: the cutting force, the chip thickness, and the chip contact area.

  17. Impact of micromechanical parameters on wire sawing: a 3D discrete element analysis

    NASA Astrophysics Data System (ADS)

    Nassauer, B.; Kuna, M.

    2015-05-01

    Wire sawing is one of the most prominent technologies for producing solar wafers. In the following paper a numerical model for the simulation of the wire sawing process at microlevel using the discrete element method is presented. The abrasive particles are represented by convex polyhedra. Based on the contact forces on the ingot, local material removal rates are calculated. These local material removal rates are then used to update the shape of the ingot in a stepwise simulation. The model allows for detailed analysis of the influence of different parameters on the micromechanical processes during wire sawing. In particular the influence of wire speed, lapping pressure, particle concentration, particle size, particle shape and debris on the sawing process is investigated. In a post-processing macroscopic process characteristics like kerf width, depth of surface cracks or sawing rate are calculated. Thus, the processes at the microlevel are related to the macroscopic process characteristics, which are of interest when applying wire sawing in practice.

  18. A Passive Wireless Multi-Sensor SAW Technology Device and System Perspectives

    PubMed Central

    Malocha, Donald C.; Gallagher, Mark; Fisher, Brian; Humphries, James; Gallagher, Daniel; Kozlovski, Nikolai

    2013-01-01

    This paper will discuss a SAW passive, wireless multi-sensor system under development by our group for the past several years. The device focus is on orthogonal frequency coded (OFC) SAW sensors, which use both frequency diversity and pulse position reflectors to encode the device ID and will be briefly contrasted to other embodiments. A synchronous correlator transceiver is used for the hardware and post processing and correlation techniques of the received signal to extract the sensor information will be presented. Critical device and system parameters addressed include encoding, operational range, SAW device parameters, post-processing, and antenna-SAW device integration. A fully developed 915 MHz OFC SAW multi-sensor system is used to show experimental results. The system is based on a software radio approach that provides great flexibility for future enhancements and diverse sensor applications. Several different sensor types using the OFC SAW platform are shown. PMID:23666124

  19. A passive wireless multi-sensor SAW technology device and system perspectives.

    PubMed

    Malocha, Donald C; Gallagher, Mark; Fisher, Brian; Humphries, James; Gallagher, Daniel; Kozlovski, Nikolai

    2013-01-01

    This paper will discuss a SAW passive, wireless multi-sensor system under development by our group for the past several years. The device focus is on orthogonal frequency coded (OFC) SAW sensors, which use both frequency diversity and pulse position reflectors to encode the device ID and will be briefly contrasted to other embodiments. A synchronous correlator transceiver is used for the hardware and post processing and correlation techniques of the received signal to extract the sensor information will be presented. Critical device and system parameters addressed include encoding, operational range, SAW device parameters, post-processing, and antenna-SAW device integration. A fully developed 915 MHz OFC SAW multi-sensor system is used to show experimental results. The system is based on a software radio approach that provides great flexibility for future enhancements and diverse sensor applications. Several different sensor types using the OFC SAW platform are shown. PMID:23666124

  20. Mixed Modeling of a SAW Delay Line Using VHDL-AMS

    NASA Technical Reports Server (NTRS)

    Wilson, William C.; Atkinson, Gary M.

    2006-01-01

    To aid in the development of SAW sensors for aerospace applications we have created a model of a SAW Delay line using VHDL. The model implements the Impulse Response method to calculate the frequency response, impedance, and insertion loss. The model includes optimization for the number of finger pairs in the IDTs and for the aperture height. This paper presents the model and the results from the model for a SAW delay line design.

  1. An Improved Performance Frequency Estimation Algorithm for Passive Wireless SAW Resonant Sensors

    PubMed Central

    Liu, Boquan; Zhang, Chenrui; Ji, Xiaojun; Chen, Jing; Han, Tao

    2014-01-01

    Passive wireless surface acoustic wave (SAW) resonant sensors are suitable for applications in harsh environments. The traditional SAW resonant sensor system requires, however, Fourier transformation (FT) which has a resolution restriction and decreases the accuracy. In order to improve the accuracy and resolution of the measurement, the singular value decomposition (SVD)-based frequency estimation algorithm is applied for wireless SAW resonant sensor responses, which is a combination of a single tone undamped and damped sinusoid signal with the same frequency. Compared with the FT algorithm, the accuracy and the resolution of the method used in the self-developed wireless SAW resonant sensor system are validated. PMID:25429410

  2. An improved performance frequency estimation algorithm for passive wireless SAW resonant sensors.

    PubMed

    Liu, Boquan; Zhang, Chenrui; Ji, Xiaojun; Chen, Jing; Han, Tao

    2014-01-01

    Passive wireless surface acoustic wave (SAW) resonant sensors are suitable for applications in harsh environments. The traditional SAW resonant sensor system requires, however, Fourier transformation (FT) which has a resolution restriction and decreases the accuracy. In order to improve the accuracy and resolution of the measurement, the singular value decomposition (SVD)-based frequency estimation algorithm is applied for wireless SAW resonant sensor responses, which is a combination of a single tone undamped and damped sinusoid signal with the same frequency. Compared with the FT algorithm, the accuracy and the resolution of the method used in the self-developed wireless SAW resonant sensor system are validated. PMID:25429410

  3. Finite element analysis of dynamic characteristics of diamond circular saw blades

    SciTech Connect

    Wang, W.; Pang, S.S.; Yang, C.; Jerro, H.D.; Mirshams, R.A.

    1997-07-01

    The diamond circular saw is an extensively used tool in stone, construction and road maintenance industries for sawing stone and concrete. However, its vibration and noise have been nuisances to users, and little literature is available concerning this subject. The major aspects of this investigation include: the first thirty five natural frequencies and resonant modes of circular saw blades of two different diameters are computed using the finite element method; based on these thirty five natural frequencies and resonant modes, the harmonic analysis is carried out to obtain their response spectrum; and through analyzing the computational results, some conclusions on the dynamic characteristics of diamond circular saw blades are reached.

  4. Corrosion inhibitors for water-base slurry in multiblade sawing

    NASA Technical Reports Server (NTRS)

    Chen, C. P.; Odonnell, T. P.

    1982-01-01

    The use of a water-base slurry instead of the standard PC oil vehicle was proposed for multiblade sawing (MBS) silicon wafering technology. Potential cost savings were considerable; however, significant failures of high-carbon steel blades were observed in limited tests using a water-based slurry during silicon wafering. Failures were attributed to stress corrosion. A specially designed fatigue test of 1095 steel blades in distilled water with various corrosion inhibitor solutions was used to determine the feasibility of using corrosion inhibitors in water-base MBS wafering. Fatigue tests indicate that several corrosion inhibitors have significant potential for use in a water-base MBS operation. Blade samples tested in these specific corrosion-inhibitor solutions exhibited considerably greater lifetime than those blades tested in PC oil.

  5. SAW1 is required for SDSA double-strand break repair in S. cerevisiae.

    PubMed

    Diamante, Graciel; Phan, Claire; Celis, Angie S; Krueger, Jonas; Kelson, Eric P; Fischhaber, Paula L

    2014-03-14

    SAW1, coding for Saw1, is required for single-strand annealing (SSA) DNA double-strand break (DSB) repair in Saccharomycescerevisiae. Saw1 physically associates with Rad1 and Rad52 and recruits the Rad1-Rad10 endonuclease. Herein we show by fluorescence microscopy that SAW1 is similarly required for recruitment of Rad10 to sites of Synthesis-Dependent Strand Annealing (SDSA) and associates with sites of SDSA repair in a manner temporally overlapped with Rad10. The magnitude of induction of colocalized Saw1-CFP/Rad10-YFP/DSB-RFP foci in SDSA is more dramatic in S and G2 phase cells than in M phase, consistent with the known mechanism of SDSA. We observed a substantial fraction of foci in which Rad10 was localized to the repair site without Saw1, but few DSB sites that contained Saw1 without Rad10. Together these data are consistent with a model in which Saw1 recruits Rad1-Rad10 to SDSA sites, possibly even binding as a protein-protein complex, but departs the repair site in advance of Rad1-Rad10. PMID:24565838

  6. Field portable detection of VOCs using a SAW/GC system

    SciTech Connect

    Staples, E.J.

    1995-12-31

    This paper describes research on a fast gas chromatography (GC) vapor analysis system which uses a new type of surface acoustic wave (SAW) detector technology to characterize organic compounds in soils and groundwater. Field testing of GC/SAW was performed at the Savannah River plant.

  7. Impact of gin saw tooth design on fiber and textile processing quality

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Toothed gin saws have been used to separate cotton fiber from the seed for over 200 years. There have been many saw tooth designs developed over the years. Most of these designs were developed by trial and error. A complete and scientific analysis of tooth design has never been done. It is not k...

  8. Saw Palmetto Extract Inhibits Metastasis and Antiangiogenesis through STAT3 Signal Pathway in Glioma Cell

    PubMed Central

    Ding, Hong; Shen, Jinglian; Yang, Yang; Che, Yuqin

    2015-01-01

    Signal transducer and activator of transcription factor 3 (STAT3) plays an important role in the proliferation and angiogenesis in human glioma. Previous research indicated that saw palmetto extract markedly inhibited the proliferation of human glioma cells through STAT3 signal pathway. But its effect on tumor metastasis and antiangiogenesis is not clear. This study is to further clear the impact of saw palmetto extract on glioma cell metastasis, antiangiogenesis, and its mechanism. TUNEL assay indicated that the apoptotic cells in the saw palmetto treated group are higher than that in the control group (p < 0.05). The apoptosis related protein is detected and the results revealed that saw palmetto extract inhibits the proliferation of human glioma. Meanwhile pSTAT3 is lower in the experimental group and CD34 is also inhibited in the saw palmetto treated group. This means that saw palmetto extract could inhibit the angiogenesis in glioma. We found that saw palmetto extract was an important phytotherapeutic drug against the human glioma through STAT3 signal pathway. Saw palmetto extract may be useful as an adjunctive therapeutic agent for treatment of individuals with glioma and other types of cancer in which STAT3 signaling is activated. PMID:26788112

  9. Finite Element Modelling of the Sawing of DC Cast AA2024 Aluminium Alloy Slabs

    NASA Astrophysics Data System (ADS)

    Drezet, J.-M.; Ludwig, O.; Heinrich, B.

    2007-04-01

    In the semi-continuous casting of large cross-section rolling sheet ingots of high-strength aluminum alloys (2xxx and 7xxx series), the control of the residual (internal) stresses generated by the non-uniform cooling becomes a necessity. These stresses must be relieved by a thermal treatment before the head and foot of the ingot can be cut. Otherwise, the saw can be caught owing to compressive stresses or cut parts may be ejected thus injuring people or damaging equipment. These high added-value ingots need to be produced in secure conditions. Moreover, a better control of the sawing procedure could allow the suppression of the thermal treatment and therefore save time and energy. By studying the stress build-up during casting and the stress relief during sawing, key parameters for the control and optimization of the processing steps, can be derived. To do so, the direct chill (DC) casting of the AA2024 alloy is modeled with ABAQUS 6.5 with special attention to the thermo-mechanical properties of the alloy. The sawing operation is then simulated by removing mesh elements so as to reproduce the progression of the saw in the ingot. Preliminary results showing the stress relief during sawing accompanied by the risk of saw blocking due to compression or initiating a crack ahead of the saw, are analyzed with an approach based on the rate of strain energy release.

  10. Separation of biological cells in a microfluidic device using surface acoustic waves (SAWs)

    NASA Astrophysics Data System (ADS)

    Ai, Ye; Marrone, Babetta L.

    2014-03-01

    In this study, a surface acoustic wave (SAW)-based microfluidic device has been developed to separate heterogeneous particle or cell mixtures in a continuous flow using acoustophoresis. The microfluidic device is comprised of two components, a SAW transducer and a microfluidic channel made of polydimethylsiloxane (PDMS). The SAW transducer was fabricated by patterning two pairs of interdigital electrodes on a lithium niobate (LiNbO3) piezoelectric substrate. When exciting the SAW transducer by AC signals, a standing SAW is generated along the cross-section of the channel. Solid particles immersed in the standing SAW field are accordingly pushed to the pressure node arising from the acoustic radiation force acting on the particles, referring to the acoustic particle-focusing phenomenon. Acoustic radiation force highly depends on the particle properties, resulting in different acoustic responses for different types of cells. A numerical model, coupling the piezoelectric effect in the solid substrate and acoustic pressure in the fluid, was developed to provide a better understanding of SAW-based particle manipulation. Separation of two types of fluorescent particles has been demonstrated using the developed SAW-based microfluidic device. An efficient separation of E. coli bacteria from peripheral blood mononuclear cell (PBMC) samples has also been successfully achieved. The purity of separated E. coli bacteria and separated PBMCs were over 95% and 91%, respectively, obtained by a flow cytometric analysis. The developed microfluidic device can efficiently separate E. coli bacteria from biological samples, which has potential applications in biomedical analysis and clinical diagnosis.

  11. Cutting crime: the analysis of the "uniqueness" of saw marks on bone.

    PubMed

    Saville, P A; Hainsworth, S V; Rutty, G N

    2007-09-01

    Witness marks produced on bone by the use of saws have traditionally been examined using stereomicroscopy. The marks are typically found on the kerf wall or floor and give important information about the implement that made them. This paper describes a new approach to the analysis of witness marks left on kerf walls and floors from crimes involving dismemberment. Previously, two types of marks have been identified: deep furrows formed during the pull stroke and fine striations formed on the push stroke. These types of striation allow the class of saw to be identified, but not an individual saw. With the advent of environmental scanning electron microscopy (ESEM), insulating materials can now be examined without the need for conductive coatings to be applied. This allows materials to be examined at higher magnifications than those available with stereomicroscopy. Here we report on a new, third type of striation that is visible at higher magnifications on ESEM images. These striations are formed from the imperfections on the cutting teeth of saws and give real possibilities of uniquely identifying whether or not a particular saw was used to cause the mark. In blind trials conducted on sawing of nylon 6.6, different individual saws could be successfully identified even if different people used the saw. We discuss ways in which these results can be extended to bone and how this may assist in the investigation of the act of dismemberment. PMID:17021897

  12. Finite Element Modelling of the Sawing of DC Cast AA2024 Aluminium Alloy Slabs

    SciTech Connect

    Drezet, J.-M.; Ludwig, O.; Heinrich, B.

    2007-04-07

    In the semi-continuous casting of large cross-section rolling sheet ingots of high-strength aluminum alloys (2xxx and 7xxx series), the control of the residual (internal) stresses generated by the non-uniform cooling becomes a necessity. These stresses must be relieved by a thermal treatment before the head and foot of the ingot can be cut. Otherwise, the saw can be caught owing to compressive stresses or cut parts may be ejected thus injuring people or damaging equipment. These high added-value ingots need to be produced in secure conditions. Moreover, a better control of the sawing procedure could allow the suppression of the thermal treatment and therefore save time and energy. By studying the stress build-up during casting and the stress relief during sawing, key parameters for the control and optimization of the processing steps, can be derived. To do so, the direct chill (DC) casting of the AA2024 alloy is modeled with ABAQUS 6.5 with special attention to the thermo-mechanical properties of the alloy. The sawing operation is then simulated by removing mesh elements so as to reproduce the progression of the saw in the ingot. Preliminary results showing the stress relief during sawing accompanied by the risk of saw blocking due to compression or initiating a crack ahead of the saw, are analyzed with an approach based on the rate of strain energy release.

  13. Pure SH-SAW propagation, transduction and measurements on KNbO3.

    PubMed

    Pollard, Thomas B; Kenny, Thomas D; Vetelino, John F; da Cunha, Mauricio Pereira

    2006-01-01

    Potassium niobate (KNbO3) supports the electromechanically active pure shear horizontal surface acoustic wave (SH-SAW) mode along Z-axis cylinder orientations, Euler angles (phi, 90 degrees, 0 degrees), in which two uncoupled wave solutions exist: a purely mechanical sagittal Rayleigh SAW and a piezoelectrically stiffened pure SH-SAW. Within this family of cuts, a maximum electromechanical coupling coefficient for the pure SH-SAW, K2 = 53%, is observed along (0 degrees, 90 degrees, 0 degrees). This pure SH-SAW orientation also has the maximum value of electromechanical coupling observed along rotated Y-cut X propagation directions, Euler angles (0 degrees, theta, 0 degrees). The use of the pure SH-SAW mode is attractive for liquid-sensing applications because the SH-SAW is modestly attenuated by the adjacent liquid, unlike the generalized SAW (GSAW), which has particle displacement normal to the surface. This work investigates propagation and excitation properties of the SH-SAW and the shear horizontal bulk acoustic wave (SH-BAW) on single crystal KNbO3, Euler angles (0 degrees, 90 degrees, 0 degrees). Interdigital transducer (IDT) arrays are analyzed using boundary element method (BEM) techniques, addressing IDT properties such as: power partitioning between the SH-SAW and SH-BAW, SH-BAW radiation as a function of wave vector direction and radiation angle, and overall IDT impedance. The percentage of SH-SAW power to total input power is above 98% for IDTs containing 1.5 to 5.5 wavelengths of active electrodes with surrounding metalized regions. For nonmetalized regions outside the IDT, the ratio drops to between 1 and 2%, showing the importance of an energy trapping structure for efficient SH-SAW excitation and propagation along this orientation. Simulated and experimental IDT admittance results are compared, verifying the validity of the analysis performed. The reported measurements on the frequency variation with temperature indicate that the orientation considered is temperature compensated at about 8 degrees C. The surface of the SH-SAW devices fabricated have been loaded with deionized water and showed additional 1.6 dB transmission loss with respect to the unloaded surface, verifying the suitability of the pure SH-SAW mode on KNbO3 for liquid sensor applications. PMID:16471447

  14. Real-time SAW measurements of NVR in cleanroom and in microenvironment

    SciTech Connect

    Liang, A.Y.; McIntyre, D.C.; Lujan, R.D.; Thornberg, S.M.; Bender, S.F.A.

    1994-05-01

    Using a real-time, Surface Acoustic Wave (SAW) sensing instrument supplied by Femtometrics, we have measured organic contamination, or nonvolatile residues (NVR), in both a cleanroom and a microenvironment. To demonstrate the {open_quotes}real-time{close_quotes} NVR detectability and sensitivity of the SAW instrument, controlled contamination experiments with photoresist material were also conducted. In addition, two cleaning methods for removing contamination from used sensors have been evaluated. One technique uses the on-board temperature varying capability of the SAW instrument, while the other technique utilizes a uv-ozone cleaner for the sensor cleaning. Preliminary results from SAW measurements in the cleanroom and in a microenvironment and tests to evaluate sensor cleaning techniques are presented in this report. A concluding summary with an assessment of the current SAW instrument and potential future applications for this technology is also presented.

  15. Calibration of the QCM/SAW Cascade Impactor for Measurement of Ozone in the Stratosphere

    NASA Technical Reports Server (NTRS)

    Wright, Cassandra K.; Sims, S. C.; Peterson, C. B.; Morris, V. R.

    1997-01-01

    The Quartz Crystal Microbalance Surface Acoustic Wave (QCM/SAW) cascade impactor collects size-fractionated distributions of aerosols on a series of 10 MHz quartz crystals and employs SAW devices coated with chemical sensors for gas detection. Presently, we are calibrating the ER-2 certified QCM/SAW cascade impactor in the laboratory for the detection of ozone. Experiments have been performed to characterize the QCM and SAW mass loading, saturation limits, mass frequency relationships, and sensitivity. We are also characterizing sampling efficiency by measuring the loss of ozone on different materials. There are parallel experiments underway to measure the variations in the sensitivity and response of the QCM/SAW crystals as a function of temperature and pressure. Results of the work to date will be shown.

  16. Circular saw-related fatalities: A rare case report, review of the literature, and forensic implications.

    PubMed

    Janík, Martin; Straka, Ľubomír; Novomeský, František; Krajčovič, Jozef; Hejna, Petr

    2016-01-01

    Fatalities attributed to powered circular saws appear to be vanishingly rare events with highly wounding and rapidly incapacitating effects. When they do occur, they are mainly self-inflicted in nature. We report the suicide committed by a 79-year-old man using a self-made circular table saw. Autopsy confirmed that the man received multiple heterogeneously distributed saw-type impacts to the head and neck resulting in complete amputation of the upper skull and partial beheading. Homemade or modified commercial sawing instruments and the resultant injuries pose a number of forensic challenges starting from the death scene investigation, continuing with technical examinations, and concluding with determining the manner of death. As with all deaths due to sharp force injuries, fatalities involving power tools such as chainsaws, circular, and band saws warrant a high degree of suspicion of criminal activity and require diligence during all phases of the death investigation. PMID:26832377

  17. Heat generation during ulnar osteotomy with microsagittal saw blades.

    PubMed

    Firoozbakhsh, K; Moneim, M S; Mikola, E; Haltom, S

    2003-01-01

    Ulnar shortening osteotomy is a surgical treatment option for patients with symptomatic ulnar positive variance for a variety of reasons. Delayed healing and nonunion of the osteotomized sites have been reported and present problematic complications of this procedure. Studies have shown nonunion rate with transverse cuts ranging from 8-15%. The goal is to achieve parallel cuts, thus maximizing the contacting bony surface area for a better union rate. The senior surgeon attempted using a custom thick blade to insure parallel cuts. The concern is whether the heat generated during such a cut would contribute to non-union. It is our hypothesis that complications with ulnar shortening osteotomy using a thick blade are secondary to excess heat generation. When generated heat surpasses the threshold temperature of bone tissue, the organic matrix is irreversibly damaged and necrosis of the bony ends may occur. The present study measured the heat generation during ulnar osteotomy using different blade thicknesses. Thirty-five fresh turkey femurs, having similar size and cortical thickness of the human ulna, were used. Loading was done at three different speeds of 0.66, 1.0, and 1.5 mm/second corresponding respectively to 30, 20, and 10 seconds for the complete cut. A general linear statistical model was fitted relating temperature rise to three predictive factors: blade thickness, sensor distance, and initial bone temperature. There was a statistically significant relationship between temperature rise and all three predictor variables at the 99% confidence level. There was no statistically significant relationship between temperature rise and the number of cuts with the same blade up to 10 times. Compared with the single microsagital saw blade, the temperature rise for the double thickness blade was 14% higher and for the triple thickness blade was 23% higher. The temperature rise was inversely related to the speed of the cut. The temperature rise for the bone cut in 30 seconds was 1.5 times higher than the temperature rise when the bone was cut in 10 seconds. Complications with ulnar shortening osteotomy may be secondary to excess heat generation. A new thick saw blade design and the use of proper internal/external irrigation may overcome the problem. PMID:14575249

  18. Laser vibrometer measurements of SAWs for nondestructive testing

    NASA Astrophysics Data System (ADS)

    Longo, Roberto; Vanlanduit, Steve; Guillaume, Patrick

    2006-06-01

    A non-destructive testing (NDT) technique should be able to calculate the position and the size of any defects, in order to measure quality and safety of materials. Complexity is an issue for most NDT tests, requiring specialist knowledge of the technique. This generally means using qualified staff, and omits the possibility of any kind of automation. In this article an experimental methodology for crack detection using Surface Acoustic Waves (SAWs) and optical laser vibrometer measurements will be introduced. The materials under test are a damaged slat track of an Airbus A320 and a steel beam (because in the zone where critical crack propagation occurs the slat track has a beam-like shape) with slots of known depth (0.2, 0.4, 0.6, 0.8 mm). The goal of this article is to compare these ultrasonic-laser measurements in order to understand how much they are suitable to detect damages and imperfections present on the material itself. For future applications, this methodology can be used to monitor the slat track during a fatigue test, to detect damages in an early stage, before a rapid crack growth.

  19. Method and apparatus for improved wire saw slurry

    DOEpatents

    Costantini, Michael A. (Hudson, NH); Talbott, Jonathan A. (Amherst, NH); Chandra, Mohan (Merrimack, NH); Prasad, Vishwanath (East Setauket, NY); Caster, Allison (Nashua, NH); Gupta, Kedar P. (Merrimack, NH); Leyvraz, Philippe (Nashua, NH)

    2000-09-05

    A slurry recycle process for use in free-abrasive machining operations such as for wire saws used in wafer slicing of ingots, where the used slurry is separated into kerf-rich and abrasive-rich components, and the abrasive-rich component is reconstituted into a makeup slurry. During the process, the average particle size of the makeup slurry is controlled by monitoring the condition of the kerf and abrasive components and making necessary adjustments to the separating force and dwell time of the separator apparatus. Related pre-separator and post separator treatments, and feedback of one or the other separator slurry output components for mixing with incoming used slurry and recirculation through the separator, provide further effectiveness and additional control points in the process. The kerf-rich component is eventually or continually removed; the abrasive-rich component is reconstituted into a makeup slurry with a controlled, average particle size such that the products of the free-abrasive machining method using the recycled slurry process of the invention are of consistent high quality with less TTV deviation from cycle to cycle for a prolonged period or series of machining operations.

  20. Comparative ecology of the Flammulated Owl and Northern Saw-whet Owl during fall migration

    USGS Publications Warehouse

    Stock, S.L.; Heglund, P.J.; Kaltenecker, G.S.; Carlisle, J.D.; Leppert, L.

    2006-01-01

    We compared the migration ecology of two owl species that exhibit different migration strategies: the Flammulated Owl (Otus flammeolus) and the Northern Saw-whet Owl (Aegolius acadicus). During fall 1999-2004, we captured 117 Flammulated Owls and 1433 Northern Saw-whet Owls in the southern Boise Mountains of southwestern Idaho. These owl species exhibited contrasting seasonal timing and body condition. Flammulated Owl captures peaked in mid-September and Northern Saw-whet Owl captures peaked in early to mid-October. Flammulated Owls displayed greater body condition than Northern Saw-whet Owls and increasing condition scores during the season, whereas Northern Saw-whet Owls had no apparent seasonal condition patterns. Based on seasonal timing of captures, both species showed unimodal movement patterns characteristic of fall migrants. However, in 1999 both species' capture rates were at least double those in other years of this study. Flammulated Owls' earlier arrival and departure, coupled with superior body condition, were consistent among years and typical of a long-distance migration strategy. In contrast, the Northern Saw-whet Owls' later arrival, more lengthy passage, and variable body condition were more characteristic of a short-distance migrant strategy. Furthermore, Northern Saw-whet Owls' body condition was significantly lower during the irruptive year than during nonirruptive years, supporting the notion that population density affects their migratory condition. ?? 2006 The Raptor Research Foundation, Inc.

  1. Development of a Wireless and Passive SAW-Based Chemical Sensor for Organophosphorous Compound Detection.

    PubMed

    Xu, Fang-Qian; Wang, Wen; Xue, Xu-Feng; Hu, Hao-Liang; Liu, Xin-Lu; Pan, Yong

    2015-01-01

    A new wireless and passive surface acoustic wave (SAW)-based chemical sensor for organophosphorous compound (OC) detection is presented. A 434 MHz reflective delay line configuration composed by single phase unidirectional transducers (SPUDTs) and three shorted reflectors was fabricated on YZ LiNbO? piezoelectric substrate as the sensor element. A thin fluoroalcoholpolysiloxane (SXFA) film acted as the sensitive interface deposited onto the SAW propagation path between the second and last reflectors of the SAW device. The first reflector was used for the temperature compensation utilizing the difference method. The adsorption between the SXFA and OC molecules modulates the SAW propagation, especially for the time delay of the SAW, hence, the phase shifts of the reflection peaks from the corresponding reflectors can be used to characterize the target OC. Prior to the sensor fabrication, the coupling of modes (COM) and perturbation theory were utilized to predict the SAW device performance and the gas adsorption. Referring to a frequency-modulated continuous wave (FMCW)-based reader unit, the developed SAW chemical sensor was wirelessly characterized in gas exposure experiments for dimethylmethylphosphonate (DMMP) detection. Sensor performance parameters such as phase sensitivity, repeatability, linearity, and temperature compensation were evaluated experimentally. PMID:26633419

  2. Hybrid Surface Acoustic Wave- Electrohydrodynamic Atomization (SAW-EHDA) For the Development of Functional Thin Films

    NASA Astrophysics Data System (ADS)

    Choi, Kyung Hyun; Kim, Hyun Bum; Ali, Kamran; Sajid, Memoon; Uddin Siddiqui, Ghayas; Chang, Dong Eui; Kim, Hyung Chan; Ko, Jeong Beom; Dang, Hyun Woo; Doh, Yang Hoi

    2015-10-01

    Conventional surface acoustic wave - electrostatic deposition (SAW-ED) technology is struggling to compete with other thin film fabrication technologies because of its limitation in atomizing high density solutions or solutions with strong inter-particle bonding that requires very high frequency (100?MHz) and power. In this study, a hybrid surface acoustic wave - electrohydrodynamic atomization (SAW-EHDA) system has been introduced to overcome this problem by integrating EHDA with SAW to achieve the deposition of different types of conductive inks at lower frequency (19.8?MHZ) and power. Three materials, Poly [2-methoxy-5-(2-ethylhexyloxy)-1, 4-phenylenevinylene] (MEH-PPV), Zinc Oxide (ZnO), and Poly(3, 4-ethylenedioxythiophene):Polystyrene Sulfonate (PEDOT:PSS) have been successfully deposited as thin films through the hybrid SAW-EHDA. The films showed good morphological, chemical, electrical, and optical characteristics. To further evaluate the characteristics of deposited films, a humidity sensor was fabricated with active layer of PEDOT:PSS deposited using the SAW-EHDA system. The response of sensor was outstanding and much better when compared to similar sensors fabricated using other manufacturing techniques. The results of the device and the films characteristics suggest that the hybrid SAW-EHDA technology has high potential to efficiently produce wide variety of thin films and thus predict its promising future in certain areas of printed electronics.

  3. SAW ethanol gas sensors based on cryptophane-A sensitive film

    NASA Astrophysics Data System (ADS)

    Sun, Ping; Jiang, Yadong; Xie, Guangzhong; Du, Xiaosong

    2010-10-01

    Surface acoustic wave (SAW) devices have been widely used for various chemical sensing applications because the sensor signal can be detected by simple and inexpensive electronics. The interactions between target analyte and the sensor surface cause changes in the mechanical, electrical, dielectric properties of the sensing coating deposited onto acoustic transducer. The changes in these properties will lead to changes in the velocity and amplitude of wave modes, which can be measured by frequency and insertion loss (IL) changes when the acoustic element is realized as a delay line or resonator. Among the different sensing coatings, the supermolecules are of considerable interest because the host molecules can be thought as original receptors allowing a specific recognition of guest molecules based on "key-lock" system. In this paper, SAW ethanol gas sensors that utilize the supermolecule of cryptophane-A as sensitive layer have been studied. We synthesized cryptophane-A from vanillyl alcohol using a double trimerisation method and deposited it on the SAW devices to fabricate cryptophane-A based SAW gas sensors. The SAW frequency and insertion loss (IL) were measured using a network analyzer. The frequency shift as the response of the cryptophane-A based SAW sensors to different concentration ethanol was measured at room temperature. It is found that the cryptophane-A based SAW sensor has high sensitivity and good reproductivity to ethanol. The frequency response increased linearly with the concentration of the ethanol.

  4. Development of a Wireless and Passive SAW-Based Chemical Sensor for Organophosphorous Compound Detection

    PubMed Central

    Xu, Fang-Qian; Wang, Wen; Xue, Xu-Feng; Hu, Hao-Liang; Liu, Xin-Lu; Pan, Yong

    2015-01-01

    A new wireless and passive surface acoustic wave (SAW)-based chemical sensor for organophosphorous compound (OC) detection is presented. A 434 MHz reflective delay line configuration composed by single phase unidirectional transducers (SPUDTs) and three shorted reflectors was fabricated on YZ LiNbO3 piezoelectric substrate as the sensor element. A thin fluoroalcoholpolysiloxane (SXFA) film acted as the sensitive interface deposited onto the SAW propagation path between the second and last reflectors of the SAW device. The first reflector was used for the temperature compensation utilizing the difference method. The adsorption between the SXFA and OC molecules modulates the SAW propagation, especially for the time delay of the SAW, hence, the phase shifts of the reflection peaks from the corresponding reflectors can be used to characterize the target OC. Prior to the sensor fabrication, the coupling of modes (COM) and perturbation theory were utilized to predict the SAW device performance and the gas adsorption. Referring to a frequency-modulated continuous wave (FMCW)-based reader unit, the developed SAW chemical sensor was wirelessly characterized in gas exposure experiments for dimethylmethylphosphonate (DMMP) detection. Sensor performance parameters such as phase sensitivity, repeatability, linearity, and temperature compensation were evaluated experimentally. PMID:26633419

  5. Hybrid Surface Acoustic Wave- Electrohydrodynamic Atomization (SAW-EHDA) For the Development of Functional Thin Films

    PubMed Central

    Choi, Kyung Hyun; Kim, Hyun Bum; Ali, Kamran; Sajid, Memoon; Uddin Siddiqui, Ghayas; Chang, Dong Eui; Kim, Hyung Chan; Ko, Jeong Beom; Dang, Hyun Woo; Doh, Yang Hoi

    2015-01-01

    Conventional surface acoustic wave - electrostatic deposition (SAW-ED) technology is struggling to compete with other thin film fabrication technologies because of its limitation in atomizing high density solutions or solutions with strong inter-particle bonding that requires very high frequency (100 MHz) and power. In this study, a hybrid surface acoustic wave - electrohydrodynamic atomization (SAW-EHDA) system has been introduced to overcome this problem by integrating EHDA with SAW to achieve the deposition of different types of conductive inks at lower frequency (19.8 MHZ) and power. Three materials, Poly [2-methoxy-5-(2-ethylhexyloxy)-1, 4-phenylenevinylene] (MEH-PPV), Zinc Oxide (ZnO), and Poly(3, 4-ethylenedioxythiophene):Polystyrene Sulfonate (PEDOT:PSS) have been successfully deposited as thin films through the hybrid SAW-EHDA. The films showed good morphological, chemical, electrical, and optical characteristics. To further evaluate the characteristics of deposited films, a humidity sensor was fabricated with active layer of PEDOT:PSS deposited using the SAW-EHDA system. The response of sensor was outstanding and much better when compared to similar sensors fabricated using other manufacturing techniques. The results of the device and the films’ characteristics suggest that the hybrid SAW-EHDA technology has high potential to efficiently produce wide variety of thin films and thus predict its promising future in certain areas of printed electronics. PMID:26478189

  6. 75 FR 13543 - Decision To Evaluate a Petition To Designate a Class of Employees for the Simonds Saw and Steel...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-22

    ... HUMAN SERVICES Decision To Evaluate a Petition To Designate a Class of Employees for the Simonds Saw and... designate a class of employees for Simonds Saw and Steel Co., Lockport, New York, to be included in the... evaluation, is as follows: Facility: Simonds Saw and Steel Co. Location: Lockport, New York. Job Titles...

  7. Assessment of Present State-of-the-art Sawing Technology of Large Diameter Ingots for Solar Sheet Material

    NASA Technical Reports Server (NTRS)

    Yoo, H. I.

    1978-01-01

    Work is reported on: (1) slicing of the ingots with the multiblade slurry saw, the multiwire slurry saw and the I.D. saw, (2) characterization of the sliced wafers, and (3) analysis of add-on slicing cost based on Solar Array Manufacturing Industry Costing Standard.

  8. [Determination of the power jigsaw sawing velocity from the morphological properties of the affected human skin].

    PubMed

    Nazarov, Iu V; Tolmachev, I A

    2014-01-01

    The objective of the present work was to elucidate the characteristic morphological features of the injuries inflicted to the human skin by a power jigsaw depending on the sawing velocity. The study has demonstrated the possibility of mathematical analysis of the sawing velocity based on the morphological peculiarities of the injury to the skin. The data obtained indicate that forensic medical expertise of the injuries inflicted by a power jigsaw can be based on the study of the width of the abraded edges of the wound in order to determine the sawing velocity. PMID:25796928

  9. Calibration of the QCM/SAW Cascade Impactor for Measurement of Ozone

    NASA Technical Reports Server (NTRS)

    Williams, Cassandra K.; Peterson, C. B.; Morris, V. R.

    1997-01-01

    The Quartz Crystal Microbalance Surface Acoustic Wave (QCM/SAW) cascade impactor is an instrument designed to collect size-fractionated distributions of aerosols on a series of quartz crystals and employ SAW devices coated with chemical sensors for gas detection. We are calibrating the cascade impactor in our laboratory for future deployment for in-situ experiments to measure ozone. Experiments have been performed to characterize the QCM and SAW mass loading, saturation limits, mass frequency relationships, and sensitivity. The characteristics of mass loading, saturation limits, mass-frequency relationships, sensitivity, and the loss of ozone on different materials have been quantified.

  10. Temperature and stiffness correction of SAW devices for wireless strain sensing

    NASA Astrophysics Data System (ADS)

    Oppenheim, Irving J.; Carey, Nicola S.; Chin, T.-L.; Zheng, Peng; Greve, David W.

    2011-04-01

    Surface acoustic wave (SAW) devices are solid-state components in which a wave propagates along the surface of a piezoelectric material. Changes in strain or temperature cause shifts in the acoustic wave speed and/or the path length, enabling SAW devices to act as sensors. We present experimental studies on lithium niobate SAW devices acting as passively-powered devices. Sensitivity, reproducibility, and linearity are excellent when measuring strain at constant temperature, but the devices are also sensitive to temperature changes. We show experimental results of strain measurement incorporating temperature compensation.

  11. Modified impedance control for robotic saw cutting: Simulation and implementation in three degrees of freedom

    SciTech Connect

    Kriikku, E.M.; Reynolds, D.L.; Carroll, J.J.; Dawson, D.M.

    1993-12-31

    The Savannah River Site (SRS) production and decommissioning operations produce solid radioactive transuranic (TRU) waste. This waste must be repackaged and sent to the Waste Isolation Pilot Plant (WIPP) for permanent disposal. The Savannah River Technology Center (SRTC) built a test facility to demonstrate simulated waste processing. The test facility use`s a CIMCORP multi-axis robot system, a CIMROC{trademark} II robot controller, and an electric circular saw to remotely open and size reduce plywood crates. The robot can either be teleoperated using joysticks or autonomously controlled via the, CIMROC{trademark} II. Both methods are inadequate for circular saw cutting of plywood crates due to frequent saw blade binding. Blade binding results from the current commercial robot controller limitations. The limitations are overcome by incorporating additional sensor information into the existing controller structure. In this paper we utilize a force sensor and a frequency counter to implement a modified impedance controller which prevents saw blade binding.

  12. Modified impedance control for robotic saw cutting: Simulation and implementation in three degrees of freedom

    SciTech Connect

    Kriikku, E.M. ); Reynolds, D.L.; Carroll, J.J.; Dawson, D.M. . School of Electrical and Computer Engineering)

    1993-01-01

    The Savannah River Site (SRS) production and decommissioning operations produce solid radioactive transuranic (TRU) waste. This waste must be repackaged and sent to the Waste Isolation Pilot Plant (WIPP) for permanent disposal. The Savannah River Technology Center (SRTC) built a test facility to demonstrate simulated waste processing. The test facility use's a CIMCORP multi-axis robot system, a CIMROC[trademark] II robot controller, and an electric circular saw to remotely open and size reduce plywood crates. The robot can either be teleoperated using joysticks or autonomously controlled via the, CIMROC[trademark] II. Both methods are inadequate for circular saw cutting of plywood crates due to frequent saw blade binding. Blade binding results from the current commercial robot controller limitations. The limitations are overcome by incorporating additional sensor information into the existing controller structure. In this paper we utilize a force sensor and a frequency counter to implement a modified impedance controller which prevents saw blade binding.

  13. Development of a Hydrogen Gas Sensor Using a Double Saw Resonator System at Room Temperature

    PubMed Central

    Yunusa, Zainab; Hamidon, Mohd Nizar; Ismail, Alyani; Isa, Maryam Mohd; Yaacob, Mohd Hanif; Rahmanian, Saeed; Ibrahim, Siti Azlida; Shabaneh, Arafat A.A

    2015-01-01

    A double SAW resonator system was developed as a novel method for gas sensing applications. The proposed system was investigated for hydrogen sensing. Commercial Surface Acoustic Wave (SAW) resonators with resonance frequencies of 433.92 MHz and 433.42 MHz were employed in the double SAW resonator system configuration. The advantages of using this configuration include its ability for remote measurements, and insensitivity to vibrations and other external disturbances. The sensitive layer is composed of functionalized multiwalled carbon nanotubes and polyaniline nanofibers which were deposited on pre-patterned platinum metal electrodes fabricated on a piezoelectric substrate. This was mounted into the DSAWR circuit and connected in parallel. The sensor response was measured as the difference between the resonance frequencies of the SAW resonators, which is a measure of the gas concentration. The sensor showed good response towards hydrogen with a minimum detection limit of 1%. PMID:25730480

  14. Slicing of single crystal and polycrystalline silicon ingots using multi-blade saws

    NASA Technical Reports Server (NTRS)

    Ross, J. B.

    1980-01-01

    Optimization of the Multi-Blade Slurry wafering technique was evaluated. Several wafering runs were made. Sufficient data necessary for a complete cost analysis of each of the three types of saw utilized are provided.

  15. Study of a high-precision SAW-MOEMS strain sensor with laser optics

    NASA Astrophysics Data System (ADS)

    Liu, Xinwei; Chen, Shufen; Li, Honglang; Zou, Zhengfeng; Fu, Lei; Meng, Yanbin

    2015-02-01

    A novel structure design of a surface acoustic wave (SAW) micro-optic-electro-mechanical-system (MOEMS) strain sensor with a light readout unit is presented in this paper. By measuring the polarization intensity ratio of the TE/TM mode outputted from the waveguide, the strain produced from an object can be measured precisely. The basic working principle of the SAW MOEMS strain sensor is introduced and the mathematical model of the strain sensor system is established. The SAW characteristics effected by the strain sensor are mathematically deduced. The coupling coefficient between the SAW modes and light modes can be calculated based on the theory of coupling modes. The conversion coefficient of polarized light modes is obtained. Due to the restrictions of the specific parameters of the device, the level of technology and the material characteristics, the sensitivity of the strain sensor system is calculated through simulation as 0.1???, with a dynamic range of 0 ~ 50???.

  16. Development of a hydrogen gas sensor using a double SAW resonator system at room temperature.

    PubMed

    Yunusa, Zainab; Hamidon, Mohd Nizar; Ismail, Alyani; Mohd Isa, Maryam; Yaacob, Mohd Hanif; Rahmanian, Saeed; Ibrahim, Siti Azlida; Shabaneh, Arafat A A

    2015-01-01

    A double SAW resonator system was developed as a novel method for gas sensing applications. The proposed system was investigated for hydrogen sensing. Commercial Surface Acoustic Wave (SAW) resonators with resonance frequencies of 433.92 MHz and 433.42 MHz were employed in the double SAW resonator system configuration. The advantages of using this configuration include its ability for remote measurements, and insensitivity to vibrations and other external disturbances. The sensitive layer is composed of functionalized multiwalled carbon nanotubes and polyaniline nanofibers which were deposited on pre-patterned platinum metal electrodes fabricated on a piezoelectric substrate. This was mounted into the DSAWR circuit and connected in parallel. The sensor response was measured as the difference between the resonance frequencies of the SAW resonators, which is a measure of the gas concentration. The sensor showed good response towards hydrogen with a minimum detection limit of 1%. PMID:25730480

  17. Wireless SAW sensor for high temperature applications: material point of view

    NASA Astrophysics Data System (ADS)

    Elmazria, Omar; Aubert, Thierry

    2011-06-01

    In addition to being small, simple and robust, surface acoustic wave (SAW) devices have the advantage of being passive (batteryless), remotely requestable (wireless) and inexpensive if fabricated on a large scale. The use of SAW devices as passive and wireless sensors allows them to operate in extreme conditions such as those with high levels of radiation, high temperatures up to 1000C, or electromagnetic interference, in which no other wireless sensor can operate. This is obviously conditioned by the fact that the materials constituting the device can withstand these harsh conditions. General principle of the SAW sensor in wireless configuration is developed and a review of recent works concerning the field of high temperature applications is presented with a specific attention given to the characterization of materials constituting the SAW device: piezoelectric substrate and metallic electrodes.

  18. Penile entrapment in a plastic bottle - a case for using an oscillating splint saw.

    PubMed

    May, Matthias; Gunia, Sven; Helke, Christian; Kheyri, Reza; Hoschke, Bernd

    2006-01-01

    Penile entrapment is a rare but serious urological emergency, which can easily lead to stangulation and infarction. We report a case of penile entrapment in a polyethylene terephthalate (PET) bottle in a 49-year-old male. Attempts to cut the bottle with a scalpel or a glass saw were ineffective. Finally, the bottle neck was cut longitudinally with an oscillating saw intended for cutting plaster casts. PMID:16502059

  19. SSBW to PSAW conversion in SAW devices using heavy mechanical loading.

    PubMed

    Fusero, Yann; Ballandras, Sylvain; Desbois, Jean; Hod, Jean-Michel; Ventura, Pascal

    2002-06-01

    The development of efficient computation tools based on mixed analytical and numerical calculation approaches allows precise descriptions and characterizations of surface acoustic waves (SAW) propagation, taking into account realistic electrical and mechanical boundary conditions. As an example, suppression of the leaky SAW, also called pseudo SAW (PSAW), attenuation has been predicted using such tools allowing to explain experimental occurrences for SAW devices on YX cut lithium niobate and lithium tantalate with thick aluminum strip gratings (6% < h/lambda < 10%). In this work, such a theoretical model is used to analyze the evolution of surface waves on standard YX lithium tantalate cuts versus aluminum strip height. It is shown that the surface skimming bulk wave (SSBW), which accompanies the pseudo SAW on such crystal orientations, may be trapped by the grating, exhibiting then a second pseudo SAW behavior when close to the Bragg condition. A device has been designed and fabricated to check these theoretical predictions. The experimental evidence of the existence of the phenomenon allows one to discuss its consequences on more classical devices built on (Y+36 degrees,X) LiTaO3 substrates. PMID:12075973

  20. Mass sensitivity calculation of the protein layer using love wave SAW biosensor.

    PubMed

    Lee, Sangdae; Kim, Ki Bok; Il Kim, Yong

    2012-07-01

    Love waves, a variety of surface acoustic waves (SAWs), can be used to detect very small biological surface interactions and so have a wide range of potential applications. To demonstrate the practicality of a Love wave SAW biosensor, we fabricated a 155-MHz Love wave SAW biosensor and compared it with a commercial surface Plasmon resonance (SPR) using glycerol-water solution with known densities and viscosities to calibrate the response signals of the biosensors. And the mass per unit area of anti-mouse IgG bound with protein G onto the sensitive layer of the biosensor was calculated on the basis of the calibration result. The sensitivity of the Love wave SAW biosensor was the same as or greater than that of the SPR biosensor. Furthermore, the Love wave SAW biosensor was capable of measuring a much wider range of viscosities than the SPR biosensor. Although the operating principle of the Love wave SAW biosensor is completely different from that of the SPR biosensor, the subtle changes in the viscoelastic properties of the biological layer that accompany biological binding reactions on the sensitive layer can be monitored and measured in the same ways as with the SPR biosensor. PMID:22966717

  1. Optimal selection of piezoelectric substrates and crystal cuts for SAW-based pressure and temperature sensors.

    PubMed

    Zhang, Xiangwen; Wang, Fei-Yue; Li, Li

    2007-06-01

    In this paper, the perturbation method is used to study the velocity shift of surface acoustic waves (SAW) caused by surface pressure and temperature variations of piezoelectric substrates. Effects of pressures and temperatures on elastic, piezoelectric, and dielectric constants of piezoelectric substrates are fully considered as well as the initial stresses and boundary conditions. First, frequency pressure/temperature coefficients are introduced to reflect the relationship between the SAW resonant frequency and the pressure/temperature of the piezoelectric substrates. Second, delay pressure/temperature coefficients are introduced to reflect the relationship among the SAW delay time/phase and SAW delay line-based sensors' pressure and temperature. An objective function for performance evaluation of piezoelectric substrates is then defined in terms of their effective SAW coupling coefficients, power flow angles (PFA), acoustic propagation losses, and pressure and temperature coefficients. Finally, optimal selections of piezo-electric substrates and crystal cuts for SAW-based pressure, temperature, and pressure/temperature sensors are derived by calculating the corresponding objective function values among the range of X-cut, Y-cut, Z-cut, and rotated Y-cut quartz, lithium niobate, and lithium tantalate crystals in different propagation directions. PMID:17571819

  2. An interrogation unit for passive wireless SAW sensors based on fourier transform.

    PubMed

    Hamsch, Matthias; Hoffmann, Rene; Buff, Werner; Binhack, Michael; Klett, Stefan

    2004-11-01

    The application of surface acoustic wave (SAW) resonators as sensor elements for different physical parameters such as temperature, pressure, and force has been well-known for several years. The energy storage in the SAW and the direct conversion from physical parameter to a parameter of the wave, such as frequency or phase, enables the construction of a passive sensor that can be interrogated wireless. This paper presents a temperature-measurement system based on passive wireless SAW sensors. The principle of SAW sensors and SAW sensor interrogation is discussed briefly. A new measurement device developed for analyzing the sensor signals is introduced. Compared to former interrogation units that detect resonance frequency of the SAW resonator by comparing amplitudes of sensor response signals related to different stimulating frequencies, the new equipment is able to measure the resonance frequency directly by calculating a Fourier transformation of the resonator response signal. Measurement results of an experimental setup and field tests are presented and discussed. PMID:15600089

  3. Ultra-wideband communication system prototype using orthogonal frequency coded SAW correlators.

    PubMed

    Gallagher, Daniel R; Kozlovski, Nikolai Y; Malocha, Donald C

    2013-03-01

    This paper presents preliminary ultra-wideband (UWB) communication system results utilizing orthogonal frequency coded SAW correlators. Orthogonal frequency coding (OFC) and pseudo-noise (PN) coding provides a means for spread-spectrum UWB. The use of OFC spectrally spreads a PN sequence beyond that of CDMA; allowing for improved correlation gain. The transceiver approach is still very similar to that of the CDMA approach, but provides greater code diversity. Use of SAW correlators eliminates many of the costly components that are typically needed in the intermediate frequency (IF) section in the transmitter and receiver, and greatly reduces the signal processing requirements. Development and results of an experimental prototype system with center frequency of 250 MHz are presented. The prototype system is configured using modular RF components and benchtop pulse generator and frequency source. The SAW correlation filters used in the test setup were designed using 7 chip frequencies within the transducer. The fractional bandwidth of approximately 29% was implemented to exceed the defined UWB specification. Discussion of the filter design and results are presented and are compared with packaged device measurements. A prototype UWB system using OFC SAW correlators is demonstrated in wired and wireless configurations. OFC-coded SAW filters are used for generation of a transmitted spread-spectrum UWB and matched filter correlated reception. Autocorrelation and cross-correlation system outputs are compared. The results demonstrate the feasibility of UWB SAW correlators for use in UWB communication transceivers. PMID:23475929

  4. Evolutionary origins and development of saw-teeth on the sawfish and sawshark rostrum (Elasmobranchii; Chondrichthyes).

    PubMed

    Welten, Monique; Smith, Moya Meredith; Underwood, Charlie; Johanson, Zerina

    2015-09-01

    A well-known characteristic of chondrichthyans (e.g. sharks, rays) is their covering of external skin denticles (placoid scales), but less well understood is the wide morphological diversity that these skin denticles can show. Some of the more unusual of these are the tooth-like structures associated with the elongate cartilaginous rostrum 'saw' in three chondrichthyan groups: Pristiophoridae (sawsharks; Selachii), Pristidae (sawfish; Batoidea) and the fossil Sclerorhynchoidea (Batoidea). Comparative topographic and developmental studies of the 'saw-teeth' were undertaken in adults and embryos of these groups, by means of three-dimensional-rendered volumes from X-ray computed tomography. This provided data on development and relative arrangement in embryos, with regenerative replacement in adults. Saw-teeth are morphologically similar on the rostra of the Pristiophoridae and the Sclerorhynchoidea, with the same replacement modes, despite the lack of a close phylogenetic relationship. In both, tooth-like structures develop under the skin of the embryos, aligned with the rostrum surface, before rotating into lateral position and then attaching through a pedicel to the rostrum cartilage. As well, saw-teeth are replaced and added to as space becomes available. By contrast, saw-teeth in Pristidae insert into sockets in the rostrum cartilage, growing continuously and are not replaced. Despite superficial similarity to oral tooth developmental organization, saw-tooth spatial initiation arrangement is associated with rostrum growth. Replacement is space-dependent and more comparable to that of dermal skin denticles. We suggest these saw-teeth represent modified dermal denticles and lack the 'many-for-one' replacement characteristic of elasmobranch oral dentitions. PMID:26473044

  5. Theoretical and Experimental Investigations to Improve the Performance of Surface Acoustic Wave (SAW) Biosensors

    NASA Astrophysics Data System (ADS)

    Richardson, Mandek

    The objective of this dissertation is to improve the performance of surface acoustic wave (SAW) biosensors for use in point-of-care-testing (POCT) applications. SAW biosensors have the ability to perform fast, accurate detection of an analyte in real time without the use of labels. However, the technology suffers from the inability to differentiate between specific and non-specific binding. Due to this limitation, direct testing of bodily fluids using SAW sensors to accurately determine an analyte's concentration is difficult. In addition, these sensors are challenged by the need to detect small concentrations of a biomarker that are typically required to give a clinical diagnosis. Sensitivity, selectivity and reliability are three critical aspects for any sensing platform. To improve sensitivity the delay path of a SAW sensor has been modified with microcavities filled with various materials. These filled cavities increased sensitivity by confining wave energy to the surface by way of constructive interference and waveguiding. Thus, the improved sensitivity will result in a lower limit of detection. In addition, insertion loss is decreased as a consequence of increased wave confinement to the surface. Sensor selectivity and reliability are adversely affected by non-specific binding of unwanted species present in a sample. To address this issue a multifunctional SAW sensor is presented. The sensor consists of two SAW delay lines oriented orthogonal to each on ST-quartz in order to generate two distinct wave modes. One wave mode is used for sensing while the other is used to remove loosely bound material. By using the same transduction mechanism for both removal and sensing, the sensor chip is simplified and complex electronics are avoided. The findings of this research involve the technological advances for SAW biosensors that make their use in POCT possible.

  6. SAW characteristics of AlN films sputtered on silicon substrates.

    PubMed

    Clement, M; Vergara, L; Sangrador, J; Iborra, E; Sanz-Hervs, A

    2004-04-01

    This article is focused on the analysis of the electroacoustic response of surface acoustic wave (SAW) filters made of aluminium nitride (AlN) thin films on various types of Si wafers. AlN films with (00.2) orientation were deposited by RF reactive sputtering of an Al target in Ar and N(2) admixtures on Si(100) and (111) wafers with resistivities ranging between 10 and 2000 Omega cm. The electroacoustic response of SAW filters with an acoustic wavelength of 40 microm was analysed by measuring the Sij parameters with a network analyser. We have determined that the out-of-band loss is directly related to the Si substrate resistivity, varying from 26 dB for 10 Omega cm to 55 dB for 2000 Omega cm. The SAW velocity depends on the orientation of the Si wafer, being approximately 4700 m/s for Si(111) and 5100 m/s for Si(100). The electroacoustic responses of the SAW filters were fitted by computations based on a simple circuital model that takes into account parasitic effects such as airborne electromagnetic coupling and conduction through the substrate. This procedure provides accurate values of the electromechanical coupling factor k2 even for devices with poor characteristics. Good quality SAW filters of AlN on high resistivity Si(100) wafers with k2 larger than 0.12% are demonstrated. PMID:15047319

  7. Effect of multiblade slurry saw induced damage on silicon solar cells

    NASA Technical Reports Server (NTRS)

    Daud, T.; Liu, J. K.; Pollock, G. A.; Koliwad, K. M.

    1978-01-01

    A correlation between the optimum etch loss and the depth of damage is established using wafers produced by the Multiblade Slurry (MBS) and the Internal Diameter (ID) saws. The observations are based on the measurement of the performance of solar cells fabricated on these wafers. Sample preparation and test results are described and the following conclusions are made: (1) the amount of silicon removal necessary for optimum solar cell performance coincides with the depth of saw-induced damage; (2) optimization of cell performance is not affected by the method of silicon removal; (3) sawing conditions should be optimized to minimize the extent of saw-induced damage; (4) the MBS saw is found to induce damage to a lesser extent; (5) since the extent of damage in MBS-sawn wafers is in the limit of etch loss required in texture etching, it is possible to achieve optimum improvement in cell performance by merely texture etching the surface of as-sawn wafers.

  8. In situ observation and measurement of the SAW thin-film acoustoelectric effect.

    PubMed

    Fisher, Brian; Malocha, Donald

    2012-03-01

    The thin-film acoustoelectric effect in SAW devices describes the interaction of electrical energy between a SAW in a piezoelectric medium and a thin film in the wave's propagation path. The real-time observation of the thin-film acoustoelectric interaction is useful in the design and characterization of SAW sensors (i.e., temperature, humidity, viscosity, voltage, current, Hall effects, etc.). An in situ test fixture was designed to be mechanically, thermally, and electrically stable. Data acquisition software and an electron beam evaporation system were configured for real-time thin-film characterization during film growth. Data have been observed for more than 20 SAW devices and over a wide range of frequencies (i.e., 62 MHz to 1 GHz). The results suggest that the use of the in situ procedure yielded good agreement between theoretical predictions and the measured data, which demonstrates a method for the characterization of a SAW H(2)-gas sensor in real-time. PMID:22481781

  9. Integrated active mixing and biosensing using surface acoustic waves (SAW) and surface plasmon resonance (SPR) on a common substrate.

    PubMed

    Renaudin, Alan; Chabot, Vincent; Grondin, Etienne; Aimez, Vincent; Charette, Paul G

    2010-01-01

    This article presents a device incorporating surface plasmon resonance (SPR) sensing and surface acoustic wave (SAW) actuation integrated onto a common LiNbO(3) piezoelectric substrate. The device uses Rayleigh-type SAW to provide active microfluidic mixing in the fluid above the SPR sensor. Validation experiments show that SAW-induced microfluidic mixing results in accelerated binding kinetics of an avidin-biotin assay. Results also show that, though SAW action causes a parasitic SPR response due to heat injection into the fluid, a relatively brief relaxation time following the SAW pulses allows the effect to dissipate, without affecting the overall assay response. Since both SPR sensors and SAW transducers can be fabricated simultaneously using low-cost microfabrication methods on a single substrate, the proposed design is well-suited to lab-on-chip applications. PMID:20024058

  10. Comparison of saw ginning and high-speed roller ginning with different lint cleaners of mid-south grown cotton

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Four cotton cultivars were ginned with a saw-gin equipment line and also with a high-speed roller-gin line. The saw-gin line using an air-jet and controlled-batt saw-type lint cleaner was compared to the high-speed roller-gin line using two versions of an experimental lint cleaner, of a basic design...

  11. Assessment of present state-of-the-art sawing technology of large diameter ingots for solar sheet material

    NASA Technical Reports Server (NTRS)

    Yoo, H. I.

    1977-01-01

    The objective of this program is to assess the present state-of-the-art sawing technology of large diameter silicon ingots (3 inch and 4 inch diameter) for solar sheet materials. During this period, work has progressed in three areas: (1) slicing of the ingots with the multiblade slurry saw and the I.D. saw, (2) characterization of the sliced wafers, and (3) analysis of direct labor, expendable material costs, and wafer productivity.

  12. Design technique for nonlinear phase SAW filters using slanted finger interdigital transducers.

    PubMed

    Yatsuda, H

    1998-01-01

    This paper describes a useful design technique to achieve a nonlinear phase SAW filter using slanted finger interdigital transducers (SFITs) or tapered interdigital transducers which are suitable for wide-band filters in intermediate frequency stages. A required nonlinear phase response in the passband can be obtained by changing center-to-center distances between input and output SFITs along an axis perpendicular to the SAW propagation axis. The design is based on a building-block approach in the frequency domain. A nonlinear phase SAW filter with a center frequency of 70 MHz and a fractional bandwidth of about 10% is demonstrated on x-cut 112.2 degrees y-propagating LiTaO(3 ). Because the substrate has a power flow angle of 1.55 degrees, the SFIT pattern is tilted along that angle. Good agreement between theoretical and experimental results is obtained. PMID:18244156

  13. Enhanced spectral efficiency using bandwidth switchable SAW filtering for mobile satellite communications systems

    NASA Technical Reports Server (NTRS)

    Peach, Robert; Malarky, Alastair

    1990-01-01

    Currently proposed mobile satellite communications systems require a high degree of flexibility in assignment of spectral capacity to different geographic locations. Conventionally this results in poor spectral efficiency which may be overcome by the use of bandwidth switchable filtering. Surface acoustic wave (SAW) technology makes it possible to provide banks of filters whose responses may be contiguously combined to form variable bandwidth filters with constant amplitude and phase responses across the entire band. The high selectivity possible with SAW filters, combined with the variable bandwidth capability, makes it possible to achieve spectral efficiencies over the allocated bandwidths of greater than 90 percent, while retaining full system flexibility. Bandwidth switchable SAW filtering (BSSF) achieves these gains with a negligible increase in hardware complexity.

  14. Bosonic See-Saw Mechanism and Its Application to Supersymmetry and Technicolor

    SciTech Connect

    Kim, Hyung Do

    2005-12-02

    We introduce the idea of bosonic see-saw mechanism in analogy with the see-saw mechanism. Bosonic see-saw is a new symmetry breaking mechanism and we apply it to explain electroweak symmetry breaking as an inevitable consequence of supersymmetry breaking. The breaking of electroweak symmetry occurs at tree level once supersymmetry is broken. Absence of color/charge breaking in this model is related to doublet-triplet splitting in grand unified theory. An extension of MSSM with a weak triplet shows very interesting results especially when {mu} = 0. It provides the most natural understanding of why we have only electroweak symmetry breaking rather than having color/charge breaking. In the limit {mu} = 0, the model predicts very light chargino mass, 104 GeV while Higgs is heavy, 130 GeV. Finally we mention the possibility of applying the same idea to technicolor idea.

  15. Investigations of bilayer sensor structure with copper phthalocyanine and palladium for hydrogen detection in SAW system

    NASA Astrophysics Data System (ADS)

    Jakubik, W. P.

    2006-11-01

    Bilayer structure with copper phthalocyanine (CuPc 100 nm) and palladium ( 18 nm), has been studied for hydrogen gas-sensing application at 30circC and 50circC temperatures. The structure was fabricated in a two different vacuum deposition processes (first the CuPc film and than the Pd) onto a LiNbO{3} Y- cut Z-propagating substrate for a SAW method and additionally (in this same technological processes) onto a glass substrate with a planar microelectrode array for simultaneously monitoring of the structure planar resistance. A good correlation has been observed between this two methods - frequency changes for SAW method coincide with decreasing of the bilayer structure resistance. Although the simultaneously measurements not always were possible (too big resistance of the sample) they can give informations about the acoustoelectric interactions between SAW and charge carriers in the bi-layer structure.

  16. Development of a generalized model to analyze time and frequency responses for SAW sensors

    NASA Astrophysics Data System (ADS)

    Tsai, Meng-Shiun; Jeng, Jie-Ting

    2011-02-01

    Most of the research on applications of wireless surface acoustic wave (SAW) sensors has focused on the fabrication process. No detailed theoretical models have been developed to illustrate the time and frequency domain characteristics of SAW devices. In this paper, the generalized model of the wireless SAW sensor is established by using the coupling-of-modes (COM) model together with the wave equations. The generalized model is developed to analyze four main applications, which include tag-ID design, the bio-reaction process, tension measurement and temperature sensing. Both the time response and frequency response are investigated to determine the appropriate signal processing for different applications. It is found that for the time response using the inverse fast Fourier transform (IFFT) is more suitable for tag-ID and the phase shift is better for bio-sensing, tension and temperature sensing. Furthermore, the developed model can be utilized to expedite the design process for wireless sensing devices.

  17. Sniffing lung cancer related biomarkers using an oxidized graphene SAW sensor

    NASA Astrophysics Data System (ADS)

    Zhang, Xin-Fang; Zhang, Zheng-Wei; He, Yan-Lan; Liu, Yi-Xing; Li, Shuang; Fang, Jing-Yue; Zhang, Xue-Ao; Peng, Gang

    2016-04-01

    Decane is one of the volatile organic compounds (VOCs) in human breath. Successful detection of decane in human breath has vast prospects for early lung cancer diagnosis. In this paper, a novel detecting device based on a filter surface acoustic wave (SAW) gas sensor is presented. SAW sensors coated with a thin oxidized graphene film were used to detect decane in parts per million (ppm) concentrations. Control and signal detection circuits were designed using a vector network analyzer with a detection resolution of insertion loss down to 0.0001 dB. The results showed that the SAW sensor could respond quickly with great sensitivity when exposed to 0.2 ppm decane. This device shows tremendous potential in medical diagnosis and environmental assessment.

  18. Accelerated binding kinetics by surface acoustic waves (SAW) micromixing in surface plasmon resonance (SPR) system for biodetection

    NASA Astrophysics Data System (ADS)

    Renaudin, Alan; Chabot, Vincent; Grondin, Etienne; Aimez, Vincent; Charette, Paul G.

    2011-02-01

    A design incorporating surface plasmon resonance (SPR) biosensing and surface acoustic wave (SAW) active microfluidic mixing, integrated on a single LiNbO3 piezoelectric substrate, is presented. Validation experiments show that SAW-mixing (microstreaming) results in accelerated binding kinetics (time-to-saturation) for a standard assay with appropriate SAW excitation parameters. Since both SPR sensors and SAW transducers can be fabricated simultaneously using low-cost microfabrication methods, the proposed design should contribute to improved lab-on-chip devices for detecting and identifying biomolecules of interest with greater accuracy and speed across multiple applications.

  19. Development of a high-sensitivity strain measurement system based on a SH SAW sensor

    NASA Astrophysics Data System (ADS)

    Oh, Haekwan; Lee, Keekeun; Eun, Kyoungtae; Choa, Sung-Hoon; Yang, Sang Sik

    2012-02-01

    A strain measurement system based on a shear horizontal surface acoustic wave (SH SAW) was developed. The developed system is composed of a SAW microsensor, a printed circuit board (PCB), an adhesive and a strain gauge. When a compression force is applied to the PCB by the strain gauge, the PCB is bent so that external strain energy can be evenly delivered to the microsensor without any detachment of the sensor from the board. When a stretching force is applied to the PCB under the condition that one side of the PCB is fixed and the other side is modulated, the actual length of the SAW delay line between the two interdigital transducers (IDTs) is increased. The increase in the delay line length causes a change in the time for the propagating SAW to reach the output IDT. If strain energy is applied to the piezoelectric substrate, the substrate density is changed, which then changes the propagation velocity of the SAW. Coupling-of-modes modeling was conducted prior to fabrication to determine the optimal device parameters. Depending on the strain, the frequency difference was linearly modulated. The obtained sensitivity for stretching was 17.3 kHz/% for the SH wave mode and split electrode. And the obtained sensitivity for bending was 46.1 kHz/% for the SH wave mode and split electrode. The SH wave showed about 15% higher sensitivity than the Rayleigh wave, and the dog-bone PCB showed about 8% higher sensitivity than the rectangular PCB. The obtained sensitivity was about five times higher than that of existing SAW-based strain sensors.

  20. Evolutionary origins and development of saw-teeth on the sawfish and sawshark rostrum (Elasmobranchii; Chondrichthyes)

    PubMed Central

    Welten, Monique; Smith, Moya Meredith; Underwood, Charlie; Johanson, Zerina

    2015-01-01

    A well-known characteristic of chondrichthyans (e.g. sharks, rays) is their covering of external skin denticles (placoid scales), but less well understood is the wide morphological diversity that these skin denticles can show. Some of the more unusual of these are the tooth-like structures associated with the elongate cartilaginous rostrum ‘saw’ in three chondrichthyan groups: Pristiophoridae (sawsharks; Selachii), Pristidae (sawfish; Batoidea) and the fossil Sclerorhynchoidea (Batoidea). Comparative topographic and developmental studies of the ‘saw-teeth’ were undertaken in adults and embryos of these groups, by means of three-dimensional-rendered volumes from X-ray computed tomography. This provided data on development and relative arrangement in embryos, with regenerative replacement in adults. Saw-teeth are morphologically similar on the rostra of the Pristiophoridae and the Sclerorhynchoidea, with the same replacement modes, despite the lack of a close phylogenetic relationship. In both, tooth-like structures develop under the skin of the embryos, aligned with the rostrum surface, before rotating into lateral position and then attaching through a pedicel to the rostrum cartilage. As well, saw-teeth are replaced and added to as space becomes available. By contrast, saw-teeth in Pristidae insert into sockets in the rostrum cartilage, growing continuously and are not replaced. Despite superficial similarity to oral tooth developmental organization, saw-tooth spatial initiation arrangement is associated with rostrum growth. Replacement is space-dependent and more comparable to that of dermal skin denticles. We suggest these saw-teeth represent modified dermal denticles and lack the ‘many-for-one’ replacement characteristic of elasmobranch oral dentitions. PMID:26473044

  1. Clustering-based pattern recognition applied to chemical recognition using SAW array signals

    SciTech Connect

    Osbourn, G.C.; Bartholomew, J.W.; Frye, G.C.; Ricco, A.J.

    1994-05-01

    We present a new patter recognition (PR) technique for chemical identification using arrays of microsensors. The technique relies on a new empirical approach to k-dimensional cluster analysis which incorporates measured human visual perceptions of difficult 2- dimensional clusters. The method can handle nonlinear SAW array data, detects both unexpected (outlier) and unreliable array responses, and has no user-adjustable parameters. We use this technique to guide the development of arrays of thin-film-coated SAW (Surface Acoustic Wave) devices that produce optimal PR performance for distinguishing a variety of volatile organic compounds, organophosphonates and water.

  2. Modeling and performance analysis of SAW reader systems for delay-line sensors.

    PubMed

    Scheiblhofer, Stefan; Schuster, Stefan; Stelzer, Andreas

    2009-10-01

    In this contribution, we present a comprehensive modeling approach for delay line-based surface acoustic wave (SAW) sensor reader systems, which provides valuable insight into the interaction of the individual system parameters. A parametric analysis of signal strength, noise, and quantization effects and consideration of important signal processing parameters, such as data windows and averaging, allows prediction of the achievable statistical measurement accuracy by closed-form solutions. The performance and capabilities of the derived model are verified on system design examples as well as multiple practical measurement scenarios, using a prototype 2.45-GHz frequency-stepped continuous-wave SAW reader system. PMID:19942515

  3. New immobilization method for SAW-biosensors: covalent attachment of antibodies via CNBr.

    PubMed

    Wessa, T; Rapp, M; Ache, H J

    1999-01-01

    Surface acoustic wave devices (SAWs) based on horizontally polarized shear waves can be used as mass-sensitive immunosensors. If the standard material, aluminium, is used for the interdigital transducers (IDTs) of these devices a pretreatment with a shielding layer of polyimide is necessary to prevent corrosion processes. However, this layer also prevents an easy covalent attachment of the necessary receptive molecules. Therefore, we developed a new activation method of this inert polyimide surface by treating with cyanogenbromide using the established cyano-transfer-technique. With a subsequent covalent attachment of anti-glucose oxidase (anti-GOD) a very sensitive SAW-immunosensor for glucose oxidase (GOD) can be obtained. PMID:10028654

  4. Aberrations in saw-tooth refractive lenses in short focal length x-ray focusing

    NASA Astrophysics Data System (ADS)

    Antimonov, Mikhail A.; Khounsary, Ali M.; Shastri, Sarvjit D.

    2013-10-01

    Saw-tooth refractive lenses (SRL) provide a comparatively attractive option for X-ray focusing for various reasons, including their simple, continuous tunability in energy and focal length. Optimal focusing of a conventional SRL at short focal lengths is limited by the SRL's length in relation to the focal length. Three approaches to overcome this limitation are described. Analytical solutions verified with ray-tracing are presented. These are bending, variation of the saw-tooth tip angles, and variation of the period.

  5. Optimization of frequency characteristics for SAW device using apodization weighting method

    NASA Astrophysics Data System (ADS)

    Zhou, Lei; Zhang, Kai-liang; Wang, Fang; Han, Ye-mei; Miao, Yin-ping; Li, Dong-mei; Liang, Sheng-fa

    2015-03-01

    In this paper, the positive influence of apodization weighting method on frequency characteristics of surface acoustic wave (SAW) temperature sensor is investigated. Simulation and experiment results show that side lobe suppression abilities of the sensor can be improved by using apodization weighting which is based on Chebyshev window. Meanwhile, we find that the side lobe of the sensor can be further restrained, when the dummy electrodes are removed. Frequency-temperature characteristics of the devices are independent of the inclusion of dummy electrodes. The apodization weighted SAW temperature sensor shows great application potential in occasions with strong electromagnetic interference.

  6. SAW-grade SiO2 for advanced microfluidic devices

    NASA Astrophysics Data System (ADS)

    Winkler, Andreas; Menzel, Siegfried; Schmidt, Hagen

    2009-05-01

    Acoustoelectronic devices based on surface acoustic wave (SAW) technology are primarily used in radio frequency filters, delay lines, duplexers, amplifiers and RFID tags. Thereby, SAW's are excited at the surface of piezoelectric materials (e.g. Quartz, LiTaO3, LiNbO3) by an RF signal applied via interdigital transducers (IDTs)1. Novel SAW applications that emerged recently in the field of microfluidics such as the handling of minimum quantities of fluids or gases2,3 require a fluid compatible design approach, high power durability and long lifetime of the devices. However, conventional SAW devices with finger electrodes arranged on top of the chip surface experience acoustomigration damage4,5 at high power input and/or higher operating temperature leading to failure of the device. Additionally, inappropriate material systems or chip surface topography can limit their performance in microfluidic application. To overcome these limitations the electrodes can be buried in an acoustically suited ("SAW-grade") functional layer which moreover should be adjustable to the specific biotechnological task. Depending on the properties of this layer, it can suppress the acoustomigration impact6 and improve the power durability of the device. Also, a reduction of the thermally-induced frequency shift is possible7. The present paper describes a novel SAW based chip technology approach using a modular concept. Here, the electrodes are buried in surface polished SAW-grade SiO2 fabricated by means of reactive RF magnetron sputtering from a SiO2- target. This approach will be demonstrated for two different metallization systems based on Al or Cu thin films on 128 YX-LiNbO3 substrates. We also show the application of the SiO2-layer with respect to compensation of thermallyinduced frequency shift and bio /chemical surface modification. Investigations were carried out using atomic force microscopy, laser-pulse acoustic measurement, glow-discharge optical emission spectroscopy, spectral reflectometry, variable angle ellipsometry and x-ray photoelectron spectroscopy. The electrode edge covering of sputter deposited SiO2 layers and the reactive ion etching of the SiO2 layers are also discussed. This modular technology gives the possibility to improve the compatibility of surface acoustic wave devices to microfluidics and generally allows the integration of SAW driven actuators (pumps and mixing devices) and sensors (sensitive to surface mass change or complex viscosity change) together with other microfluidic elements (e.g. electrophoresis, heating elements) on one chip.

  7. Early development of rostrum saw-teeth in a fossil ray tests classical theories of the evolution of vertebrate dentitions.

    PubMed

    Smith, Moya Meredith; Riley, Alex; Fraser, Gareth J; Underwood, Charlie; Welten, Monique; Kriwet, Jürgen; Pfaff, Cathrin; Johanson, Zerina

    2015-10-01

    In classical theory, teeth of vertebrate dentitions evolved from co-option of external skin denticles into the oral cavity. This hypothesis predicts that ordered tooth arrangement and regulated replacement in the oral dentition were also derived from skin denticles. The fossil batoid ray Schizorhiza stromeri (Chondrichthyes; Cretaceous) provides a test of this theory. Schizorhiza preserves an extended cartilaginous rostrum with closely spaced, alternating saw-teeth, different from sawfish and sawsharks today. Multiple replacement teeth reveal unique new data from micro-CT scanning, showing how the 'cone-in-cone' series of ordered saw-teeth sets arrange themselves developmentally, to become enclosed by the roots of pre-existing saw-teeth. At the rostrum tip, newly developing saw-teeth are present, as mineralized crown tips within a vascular, cartilaginous furrow; these reorient via two 90° rotations then relocate laterally between previously formed roots. Saw-tooth replacement slows mid-rostrum where fewer saw-teeth are regenerated. These exceptional developmental data reveal regulated order for serial self-renewal, maintaining the saw edge with ever-increasing saw-tooth size. This mimics tooth replacement in chondrichthyans, but differs in the crown reorientation and their enclosure directly between roots of predecessor saw-teeth. Schizorhiza saw-tooth development is decoupled from the jaw teeth and their replacement, dependent on a dental lamina. This highly specialized rostral saw, derived from diversification of skin denticles, is distinct from the dentition and demonstrates the potential developmental plasticity of skin denticles. PMID:26423843

  8. Early development of rostrum saw-teeth in a fossil ray tests classical theories of the evolution of vertebrate dentitions

    PubMed Central

    Smith, Moya Meredith; Riley, Alex; Fraser, Gareth J.; Underwood, Charlie; Welten, Monique; Kriwet, Jürgen; Pfaff, Cathrin; Johanson, Zerina

    2015-01-01

    In classical theory, teeth of vertebrate dentitions evolved from co-option of external skin denticles into the oral cavity. This hypothesis predicts that ordered tooth arrangement and regulated replacement in the oral dentition were also derived from skin denticles. The fossil batoid ray Schizorhiza stromeri (Chondrichthyes; Cretaceous) provides a test of this theory. Schizorhiza preserves an extended cartilaginous rostrum with closely spaced, alternating saw-teeth, different from sawfish and sawsharks today. Multiple replacement teeth reveal unique new data from micro-CT scanning, showing how the ‘cone-in-cone’ series of ordered saw-teeth sets arrange themselves developmentally, to become enclosed by the roots of pre-existing saw-teeth. At the rostrum tip, newly developing saw-teeth are present, as mineralized crown tips within a vascular, cartilaginous furrow; these reorient via two 90° rotations then relocate laterally between previously formed roots. Saw-tooth replacement slows mid-rostrum where fewer saw-teeth are regenerated. These exceptional developmental data reveal regulated order for serial self-renewal, maintaining the saw edge with ever-increasing saw-tooth size. This mimics tooth replacement in chondrichthyans, but differs in the crown reorientation and their enclosure directly between roots of predecessor saw-teeth. Schizorhiza saw-tooth development is decoupled from the jaw teeth and their replacement, dependent on a dental lamina. This highly specialized rostral saw, derived from diversification of skin denticles, is distinct from the dentition and demonstrates the potential developmental plasticity of skin denticles. PMID:26423843

  9. SAW COM-parameter extraction in AlN/diamond layered structures.

    PubMed

    Iriarte, Gonzalo F; Engelmark, Fredrik; Katardjiev, Ilia V; Plessky, Viktor; Yantchev, Ventsislav

    2003-11-01

    Highly c-axis oriented aluminum nitride (AlN) thin piezoelectric films have been grown on polycrystalline diamond substrates by pulsed direct current (DC) magnetron reactive sputter-deposition. The films were deposited at a substrate temperature below 50 degrees C (room temperature) and had a typical full width half maximum (FWHM) value of the rocking curve of the AlN-002-peak of 2.1 degrees. A variety of one-port surface acoustic wave (SAW) resonators have been designed and fabricated on top of the AlN films. The measurements indicate that various SAW modes are excited. The SAW phase velocities of up to 11.800 m/s have been measured. These results are in agreement with calculated dispersion curves of the AlN/diamond structure. Finally, the coupling of modes parameters have been extracted from S11 measurements using curve fitting for the first SAW mode, which indicate an effective coupling K2 of 0.91% and a Q factor of about 600 at a frequency of 1050 MHz. PMID:14682637

  10. Capped guanidino-?-cyclodextrin first synthesis based on intramolecular Staudinger-Aza-Wittig (SAW) reaction.

    PubMed

    Couturier, C; Dumarcay-Charbonnier, F; Lambert, A; Barth, D; Marsura, A

    2014-11-01

    An intramolecularly promoted SAW reaction between a phosphinimide and an isocyanate intermediate led to an original bridged trisubstituted ((A,C),E)-?-cyclodextrin. The latter was in a second step converted into a new capped (ACE)-(guanidino)-?-cyclodextrin. PMID:25438653

  11. Instructional Media Production for Early Childhood Education: A. B. C. Jig-Saw Puzzle, a Model

    ERIC Educational Resources Information Center

    Yusuf, Mudashiru Olalere; Olanrewaju, Olatayo Solomon; Soetan, Aderonke K.

    2015-01-01

    In this paper, a. b. c. jig-saw puzzle was produced for early childhood education using local materials. This study was a production based type of research, to serve as a supplemental or total learning resource. Its production followed four phases of development referred to as information, design, production and evaluation. The storyboard cards,…

  12. Machine Shop. Module 4: Power Saw and Drill Press Operation. Instructor's Guide.

    ERIC Educational Resources Information Center

    Walden, Charles H.; Daniel, Bill

    This document consists of materials for a six-unit course on the following topics: (1) power saw safety and maintenance; (2) cutting stock to length; (3) band machining and contouring; (4) drill press types and safety; (5) drill press work-holding devices; and (6) tools and tool holders. The instructor's guide begins with a list of competencies

  13. Effects of Friction Reduction on Fiber Damage in a Saw-Type Lint Cleaner

    Technology Transfer Automated Retrieval System (TEKTRAN)

    U.S. cotton is at a competitive disadvantage from a fiber-quality standpoint, because lint cleaning is required for mechanically harvested cotton, and lint cleaning causes fiber damage. Lint-cleaning research has focused mainly on modifying saw-type lint cleaners, but the work reported here focuses...

  14. An experimental study of the physiological effects of chain saw operation.

    PubMed Central

    Miyakita, T; Miura, H; Futatsuka, M

    1987-01-01

    This experimental study was designed to determine whether a combination of noise and vibration produced more pronounced changes in temporary shifts of finger skin temperature and temporary threshold shift (TTS) of hearing than those resulting from exposure to either stress alone. Nineteen healthy subjects were exposed to six different combinations of vibration, noise, and handle holding by using a chain saw for a pre-determined time. The mean value of normalised finger skin temperature decreased much more when the subjects operated a chain saw at high speed (exposure 1) than when they operated the chain saw with the noise isolated by double hearing protection (exposure 2). In five of the 14 subjects significantly larger TTS values at 4 kHz were observed in the former condition (exposure 1) compared with the values obtained when they stood beside someone else operating a chain saw (exposure 3). The results of this study suggest that noise may play a part in inducing the constriction of the peripheral vessels seen with local exposure to vibration, and that hand-arm vibration may produce an additive effect on the noise induced TTS. PMID:3814533

  15. Application of the see-saw method to all refracting optical systems

    NASA Astrophysics Data System (ADS)

    Rosete-Aguilar, Martha

    1996-04-01

    The optical see-saw diagram is a method that describes image correction to third-order approximation over a finite field of view in rotationally symmetric systems that employ aspheric surfaces. The aim of this paper is to describe the correction of aberrations caused by plane surfaces in all refracting optical systems in terms of the see-saw diagram. A lens correction algorithm based on the see-saw method is described to correct analytically the Seidel aberrations, primary spherical aberration, coma, astigmatism, and distortion, in such systems. We then apply this lens correction algorithm to the design of equivalent configurations by aspherizing different surfaces of the system, and the high-order aberrations of the equivalent configurations are evaluated by means of transverse-ray-aberration plots. Results indicate that this method gives information on what the contribution must be to the third-order aberrations that each component should provide to the system to give a better balance of high-order aberrations. Examples of the lens correction algorithm applied to lenses with six refracting surfaces and working for both finite and infinite object conjugates are given. aberrations, see-saw method.

  16. SAW/GC detection of taggants and other volatile compounds associated with contraband materials

    NASA Astrophysics Data System (ADS)

    Staples, Edward J.; Watson, Gary W.; McGuirre, David S.; Williams, Dudley

    1997-02-01

    Research on a Surface Acoustic Wave (SAW) Gas Chromatography (GC) non-intrusive inspection system has demonstrated the ability to identify and quantify the presence of non- volatile contraband vapors in less than 10 seconds. The technique can be used to detect volatile compounds associated with the contraband compound as well. This is important because volatile taggants in explosives make them easy to detect and volatile organic compounds are routinely used in the manufacturing of illicit drugs. The results of tests with volatile organic compounds associated with drugs of abuse, and volatile taggants for explosives are presented. The latter materials are particularly useful in detecting plastic explosives and results for Semtex and C-4 spiked with a taggant show that detectability is improved. Similar testing protocols and methods for drugs, currency, organo-phosphate agents, and taggant compounds have also been demonstrated. The SAW/GC method needs no high voltages, utilizes essentially all solid state devices, and involves no radioactive or hazardous materials SAW detection systems have demonstrated dynamic ranges greater than 1,000,000 and the ability to selectively screen for vapors from explosive and drugs of abuse at the part per billion level with little or no interference. Most important for law-enforcement, SAW/GC devices can be produced in small packages at low cost.

  17. Development of fuzzy logic system to predict the SAW weldment shape profiles

    NASA Astrophysics Data System (ADS)

    Narang, H. K.; Mahapatra, M. M.; Jha, P. K.; Biswas, P.

    2012-09-01

    A fuzzy model was presented to predict the weldment shape profile of submerged arc welds (SAW) including the shape of heat affected zone (HAZ). The SAW bead-on-plates were welded by following a full factorial design matrix. The design matrix consisted of three levels of input welding process parameters. The welds were cross-sectioned and etched, and the zones were measured. A mapping technique was used to measure the various segments of the weld zones. These mapped zones were used to build a fuzzy logic model. The membership functions of the fuzzy model were chosen for the accurate prediction of the weld zone. The fuzzy model was further tested for a set of test case data. The weld zone predicted by the fuzzy logic model was compared with the experimentally obtained shape profiles and close agreement between the two was noted. The mapping technique developed for the weld zones and the fuzzy logic model can be used for on-line control of the SAW process. From the SAW fuzzy logic model an estimation of the fusion and HAZ can also be developed.

  18. Production Machine Shop Employment Competencies. Part Two: Saws, Drills, and Grinders.

    ERIC Educational Resources Information Center

    Bishart, Gus; Werner, Claire

    Competencies for production machine shop are provided for the second of four topic areas: saws, drills, and grinders. Each competency appears in a one-page format. It is presented as a goal statement followed by one or more "indicator" statements, which are performance objectives describing an ability that, upon attainment, will establish…

  19. Production Machine Shop Employment Competencies. Part Two: Saws, Drills, and Grinders.

    ERIC Educational Resources Information Center

    Bishart, Gus; Werner, Claire

    Competencies for production machine shop are provided for the second of four topic areas: saws, drills, and grinders. Each competency appears in a one-page format. It is presented as a goal statement followed by one or more "indicator" statements, which are performance objectives describing an ability that, upon attainment, will establish

  20. 77 FR 8751 - Table Saw Blade Contact Injuries; Reopening of the Comment Period

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-15

    ... accidental contact with the blade. In the Federal Register of July 9, 2003 (68 FR 40912) and September 5... blade contact injuries in the Federal Register of October 11, 2011 (76 FR 62678). CPSC staff also... warnings and instructions to address table saw blade contact injuries (76 FR at 62683). The ANPR...

  1. 76 FR 75504 - Table Saw Blade Contact Injuries; Notice of Extension of Time for Comments

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-02

    ... protect the user from accidental contact with the blade. In the Federal Register of July 9, 2003 (68 FR... rule requiring specified warnings and instructions to address table saw blade contact injuries (76 FR... Act (``CPSA''), 15 U.S.C. 2051-2084. In the Federal Register of October 11, 2011 (76 FR 62678),...

  2. Neutrino Oscillation Parameters in a Six-channel Reduced Rank See-Saw

    SciTech Connect

    Stephenson, G. J. Jr.; Goldman, T.; McKellar, B. H. J.

    2006-07-11

    We demonstrate that it is possible to find parameters in a rank one see-saw model which give a reasonable representation of atmospheric neutrino data and of the LSND result. Solar neutrino data will require a complete description of the matter effect in the six channel space.

  3. 78 FR 31897 - Agency Information Collection Activities; Proposed Collection; Comment Request; CPSC Table Saw...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-28

    ... (ANPR) for table saws, under the Consumer Product Safety Act (CPSA), 15 U.S.C. 2051-2084. (76 FR 62678... injuries. 76 FR 62683. Currently, the CPSC does not know how consumers are using the new modular blade... COMMISSION Agency Information Collection Activities; Proposed Collection; Comment Request; CPSC Table...

  4. Surface Acoustic Wave (SAW) biosensors: coupling of sensing layers and measurement.

    PubMed

    Lnge, Kerstin; Gruhl, Friederike J; Rapp, Michael

    2013-01-01

    Surface acoustic wave (SAW) devices based on horizontally polarized surface shear waves enable direct and label-free detection of proteins in real time. Signal response changes result mainly from mass increase and viscoelasticity changes on the device surface. With an appropriate sensor configuration all types of binding reactions can be detected by determining resonant frequency changes of an oscillator. To create a biosensor, SAW devices have to be coated with a sensing layer binding specifically to the analyte. Intermediate hydrogel layers used within the coating have been proven to be very suitable to easily immobilize capture molecules or ligands corresponding to the analyte. However, aside from mass increase due to analyte binding, the SAW signal response in a subsequent binding experiment strongly depends on the morphology of the sensing layer, as this may lead to different relative changes of viscoelasticity. Bearing these points in mind, we present two basic biosensor coating procedures, one with immobilized capture molecule and a second with immobilized ligand, allowing reliable SAW biosensor signal responses in subsequent binding assays. PMID:23329462

  5. On the Modeling of Electrical Response of SAW Resonator-based Sensors Versus Temperature

    NASA Astrophysics Data System (ADS)

    Ballandras, S.; Laroche, T.; Courjon, E.; Daniau, W.; Baron, T.; Garcia, J.; Alzuaga, S.

    Surface acoustic wave (SAW) resonators built on Langasite (LGS) are capable to withstand temperature in excess of 900? C and demonstration of wireless interrogation of packaged sensors up to 700? C has been achieved for several tens of hours. These promising results emphasize the need for an accurate characterization of the raw material in order to design SAW resonators with a high level of confidence in the prediction, particularly concerning the temperature coefficient of frequency (TCF). Several data set have been published for LGS, offering prediction capabilities but also a significant level of data dispersion. Therefore, the evaluation of the effective thermal properties of SAW under periodic gratings turns out less robust than expected. Based also on published data and on measurements achieved within the SAWHOT project, harmonic admittance calculations have been achieved for deriving the evolution of mixed matrix parameters allowing for accurate SAW device simulation at any temperature. Adjusting the temperature coefficients then yield improved sets of material coefficients for design purpose. Using these data, we have demonstrated the possibility to develop a differential temperature sensor operating at temperature up to 600C.

  6. Simultaneous and wireless measurement of CO2 and humidity using a SAW reflective delay line

    NASA Astrophysics Data System (ADS)

    Lim, Chunbae; Wang, Wen; Lee, Keekeun; Oh, Hae-Kwan; Yang, Sangsik

    2009-02-01

    A 440MHz wireless and passive surface acoustic wave (SAW) based chemical sensor was developed for simultaneous measurement of CO2 gas and relative humidity (RH) using a reflective delay line pattern as the sensor element. The reflective delay line was structured by an inter-digital transducer (IDT) and several shorted grating reflectors positioned both sites of the IDTs along the SAW propagation direction. A Teflon AF 2400 film with large solubility, permeability, and selectivity towards to CO2 and a hydrophilic SiO2 layer for water vapor sensing are used as the sensitive film and deposited onto the piezoelectric substrate. A simulation on the SAW device was performed using the coupling of modes (COM). The measured reflection coefficient S11 in time domain of the fabricated SAW device shows sharp reflection peaks with high signal-to-noise (S/N) ratio, small signal attenuation, and few spurious peaks. During the CO2 and humidity testing, high sensitivity (~2o ppm-1 for CO2 detection and 7.45o/%RH for humidity sensing), good linearity and repeatability were observed in the CO2 concentration of 50~400ppm and humidity of 20~80%RH. Temperature and humidity compensations were also investigated during the sensitivity evaluation process.

  7. Detection/classification/quantification of chemical agents using an array of surface acoustic wave (SAW) devices

    NASA Astrophysics Data System (ADS)

    Milner, G. Martin

    2005-05-01

    ChemSentry is a portable system used to detect, identify, and quantify chemical warfare (CW) agents. Electro chemical (EC) cell sensor technology is used for blood agents and an array of surface acoustic wave (SAW) sensors is used for nerve and blister agents. The combination of the EC cell and the SAW array provides sufficient sensor information to detect, classify and quantify all CW agents of concern using smaller, lighter, lower cost units. Initial development of the SAW array and processing was a key challenge for ChemSentry requiring several years of fundamental testing of polymers and coating methods to finalize the sensor array design in 2001. Following the finalization of the SAW array, nearly three (3) years of intensive testing in both laboratory and field environments were required in order to gather sufficient data to fully understand the response characteristics. Virtually unbounded permutations of agent characteristics and environmental characteristics must be considered in order to operate against all agents and all environments of interest to the U.S. military and other potential users of ChemSentry. The resulting signal processing design matched to this extensive body of measured data (over 8,000 agent challenges and 10,000 hours of ambient data) is considered to be a significant advance in state-of-the-art for CW agent detection.

  8. Advances in SAW Gas Sensors Based on the Condensate-Adsorption Effect

    PubMed Central

    Liu, Jiuling; Wang, Wen; Li, Shunzhou; Liu, Minghua; He, Shitang

    2011-01-01

    A surface-acoustic-wave (SAW) gas sensor with a low detection limit and fast response for volatile organic compounds (VOCs) based on the condensate-adsorption effect detection is developed. In this sensor a gas chromatography (GC) column acts as the separator element and a dual-resonator oscillator acts as the detector element. Regarding the surface effective permittivity method, the response mechanism analysis, which relates the condensate-adsorption effect, is performed, leading to the sensor performance prediction prior to fabrication. New designs of SAW resonators, which act as feedback of the oscillator, are devised in order to decrease the insertion loss and to achieve single-mode control, resulting in superior frequency stability of the oscillator. Based on the new phase modulation approach, excellent short-term frequency stability (3 Hz/s) is achieved with the SAW oscillator by using the 500 MHz dual-port resonator as feedback element. In a sensor experiment investigating formaldehyde detection, the implemented SAW gas sensor exhibits an excellent threshold detection limit as low as 0.38 pg. PMID:22247697

  9. Seed Germination Methods and Establishment of Saw-Palmetto, Serenoa Repens, in South Texas

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Saw-pametto, Serenoa repens, a native of Florida rangelands, and used medicinally in prostate formulations, was evaluated as an alternative crop for South Texas (USA). Fresh seeds, obtained from the USDA Plant Introduction Station, Miami, Florida on Oct.28, 1999, were sown directly into artificial ...

  10. MTR, TRA603. INCANAL CONVEYOR TABLE, SAW TABLE, AND STORAGE AREA ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    MTR, TRA-603. IN-CANAL CONVEYOR TABLE, SAW TABLE, AND STORAGE AREA RACKS. DISCHARGE MECHANISM. BLAW-KNOX 3150-579-1, 12/1950. INL INDEX NO. 531-603-40-098-100302, REV. 3. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

  11. The Income Volatility See-Saw: Implications for School Lunch. ERS Report Summary

    ERIC Educational Resources Information Center

    Newman, Constance

    2006-01-01

    Income volatility challenges the functioning of the safety net provided by U.S. Department of Agriculture (USDA) food assistance programs for low-income families in time of need. Low-income families may be on a see-saw of income changes that make it difficult for program administrators to accurately target benefits and to define sensible…

  12. Observing the motion of seed coat fragments on a saw-type lint cleaner

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A study was conducted to observe how seed coat fragments (in ginned lint) reacted after colliding with grid bars mounted on a full-size saw-type lint cleaner. A high-speed video camera recorded the collision. A 45° and 105° grid bar were used in the study. The grid bars were labeled to describe t...

  13. Buzz-saw noise: Prediction of the rotor-alone pressure field

    NASA Astrophysics Data System (ADS)

    McAlpine, A.; Schwaller, P. J. G.; Fisher, M. J.; Tester, B. J.

    2012-10-01

    Public expectations of lower environmental noise levels, and increasingly stringent legislative limits on aircraft noise, result in noise being a critical technical issue in the development of jet engines. Noise at take-off, when the engines are at high-power operating conditions, is a key reference level for engine noise certification. "Buzz-saw" noise is the dominant fan tone noise from modern high-bypass-ratio turbofan aircraft engines during take-off. Rotor-alone tones are the key component of buzz-saw noise. The rotor-alone pressure field is cut-off at subsonic fan tip speeds; buzz-saw noise is associated with supersonic fan tip speeds, or equivalently, high power engine operating conditions. A recent series of papers has described new work concerning the prediction of buzz-saw noise. The prediction method is based on modelling the nonlinear propagation of one-dimensional sawtooth waveforms. A sawtooth waveform is a simplified representation of the rotor-alone pressure field. Previous validation of the prediction method focussed entirely on reproducing the spectral characteristics of buzz-saw noise; this was dictated at that time by the availability of spectral data only for comparison between measurement and prediction. In this paper, full validation of the method by comparing measurement and prediction of the rotor-alone pressure field is published for the first time. It is shown that results from the modelling based on a one-dimensional sawtooth waveform capture the essential features of the rotor-alone pressure field as it propagates upstream inside a hard-walled inlet duct. This verifies that predictions of the buzz-saw noise spectrum, which are in good agreement with the measured data, are based on a model which reproduces the key physics of the noise generation process. Validation results for the rotor-alone pressure field in an acoustically lined inlet duct are also shown. Comparisons of the measured and predicted rotor-alone pressure field are more difficult to interpret because the acoustic lining significantly modifies the sawtooth waveform, but there remains good agreement with the measured spectral data. The buzz-saw noise prediction code used to generate the simulations in this paper has been used by the Rolls-Royce Noise Department since 2004.

  14. Wavenumber domain analysis of two-dimensional SAW images captured by phase-sensitive laser probe system.

    PubMed

    Hashimoto, Ken-ya; Kamizuma, Hiroshi; Watanabe, Masashi; Omori, Tatsuya; Yamaguchi, Masatsune

    2007-05-01

    This paper is aimed at demonstrating how the wavenumber domain analysis of two-dimensional (2-D) images captured by phase-sensitive laser probe systems is applied in the characterization of RF SAW devices. Effectiveness is demonstrated through the selective characterization of spurious resonance modes and scattered, nonguided modes appearing in SAW resonators. PMID:17523572

  15. Comparison of Saw Palmetto (extract and whole berry) and Cernitin on prostate growth in rats.

    PubMed

    Talpur, Nadeem; Echard, Bobby; Bagchi, Debasis; Bagchi, Manashi; Preuss, Harry G

    2003-08-01

    Pharmaceuticals such as finasteride and alpha blockers are used to treat symptoms of benign prostatic hyperplasia (BPH) and are known to cause severe adverse reactions. Accordingly, a search for safer, natural products has been undertaken. Two natural agents (nutraceuticals) have come under recent scrutiny; because natural products, in general, often have evidence of long-term safety. The present study compares the in vivo effects on androgen-induced prostatic enlargement in rats of two nutraceuticals--the widely recognized Saw Palmetto (Serenoa repens) and the less well-known Cernitin (defined pollen extract). Non-castrated rats, had a mean prostate weight of 124 mg +/- 8.8 (S.E.M.) compared to the 24.5 mg +/- 1.9 (S.E.M.) of the castrated rat followed under the same regimen (p < 0.01). When castrated rats were given testosterone, the mass increased significantly to 250.0 mg +/- 31.7 (S.E.M.) (p < 0.01). In the five remaining groups, castrated rats receiving testosterone were given finasteride, an extract of Saw Palmetto, crushed whole berry derived from Saw Palmetto fruit, a water soluble and fat soluble extract of Cernitin or a combination of the Saw Palmetto extract and Cernitin. All treatments decreased the size of the prostate to roughly the same size as in the non-castrated rats, a size that was significantly smaller than castrated rats treated with testosterone in the same manner (p < 0.01). A second study examining non-castrated rats treated with very high doses of testosterone showed similar results. In both studies, the nutraceuticals generally decreased body weight. In conclusion, these studies show the ability of Saw Palmetto (whole berry and extract) and Cernitin to influence prostatic hyperplasia via effects on androgen metabolism. PMID:12962139

  16. Determination and experimental verification of high-temperature SAW orientations on langatate.

    PubMed

    Davulis, Peter M; da Cunha, Mauricio Pereira

    2012-02-01

    Langatate (LGT) is a member of the langasite family of crystals appropriate for high-temperature frequency control and sensing applications. This paper identifies multiple LGT SAW orientations for use at high temperature, specifically in the 400C to 900C range. Orientations with low sensitivity to temperature are desired for frequency control devices and many sensors, conversely large temperature sensitivity is a benefit for temperature sensors. The LGT SAW temperature behavior has been calculated for orientations sweeping the Euler angles (0, ?, ?), (90, ?, ?), and (?, 90, ?), based on newly identified high-temperature elastic constants and temperature coefficients for this material. The temperature coefficient of delay (TCD) and total frequency change over the temperature range were analyzed from 400C to 900C. Multiple SAW orientations were identified with zero-TCD between 400C and 500C. Although no orientations that have turn-over temperatures above 500C were identified, several have low frequency variation with temperature, of the order of -0.8% over the range 400C to 800C. Temperature-sensitive orientations with TCD up to 75 ppm/C at 900C were identified, with potential for high-temperature sensor applications. The reported predictions are shown to agree with measured behavior of LGT SAW delay lines fabricated along 6 orientations in the (90, 23, ?) plane. In addition, this work demonstrates that concurrently operated LGT SAW devices fabricated on the same wafer provide means of temperature sensing. In particular, the measured frequency difference between delay lines oriented along (90, 23, 0) and (90, 23, 48) has fractional temperature sensitivity that ranges from -172 ppm/C at 25C to -205 ppm/C at 900C. PMID:24626037

  17. Radiative Efficiency Enhancement in Blue Saw-Like InGaN/GaN Light-Emitting Diodes

    NASA Astrophysics Data System (ADS)

    Park, Seoung-Hwan

    2013-05-01

    Light emission characteristics of saw-like blue InGaN/GaN quantum well (QW) light-emitting diodes (LEDs) are theoretically investigated using the multiband effective mass theory. The saw-like QW structure has several advantages such as the enhancement in light emission, the reduction in the quantum Stark effect, and the increase in the internal efficiency, compared with a conventional InGaN/GaN QW structure. The increase in the spontaneous emission peak of the saw-like QW structure is mainly attributed to the fact that the electron wavefunction is shifted toward the left side with the inclusion of the saw-like layer while the hole wavefunction is nearly invariant. The internal efficiency of the saw-like QW structure is shown to be much larger than that of a conventional QW structure. Hence, we expect that this structure can be used as high-efficiency blue InGaN/GaN LEDs.

  18. Room temperature fabrication of ZnO/ST-cut quartz SAW UV photodetector with small temperature coefficient.

    PubMed

    Tsai, Wen-Che; Kao, Hui-Ling; Liao, Kun-Hsu; Liu, Yu-Hao; Lin, Tzu-Ping; Jeng, Erik S

    2015-02-01

    Room-temperature fabricated ZnO/ST-cut quartz is adopted for SAW ultraviolet (UV) photodetector. The ST-cut quartz substrate and ZnO layer are used for SAW excitation and photodetection, respectively. High resolution x-ray diffraction (XRD) and photoluminescence (PL) measurement indicate that high quality ZnO films can be deposited on ST-cut quartz using radio frequency (RF) sputtering. As the SAW devices under UV illumination (6 mW/cm(2)), a downshift in frequency of about 35 KHz can be observed. The observed small temperature coefficient of frequency (TCF) indicates that SAW devices exhibit good temperature stability. The results present feasibility of using ZnO/ST-cut quartz SAW photodetectors in ultraviolet region. PMID:25836089

  19. Design and use of multiple blade slurry sawing in a production atmosphere

    NASA Technical Reports Server (NTRS)

    Lynah, F. P., Jr.; Ross, J. B.

    1982-01-01

    The technique and uses of the multiple blade slurry (MBS) saw are considered. Multiple bands of steel are arranged in a frame and the frame is reciprocated with the steel bands to a workpiece, while simultaneously applying abrasive at the point of contact. The blades wear slots in the workpiece and progress through the piece resulting in several parts of wafers. The transition to MBA from diamond slicing is justified by savings resulting from minimized kerf losses, minimized subsurface damage, and improved surface quality off the saw. This allows wafering much closer to finished thickness specifications. The current state of the art MBS technology must be significantly improved if the low cost solar array (LSA) goals are to be attained. It is concluded that although MBS will never be the answer to every wafering requirement, the economical production of wafers to LSA project specifications will be achieved.

  20. New materials and multidimensional cluster analysis for SAW chemical sensor arrays

    SciTech Connect

    Ricco, A.J.; Osbourn, G.C.; Bartholomew, J.W.; Crooks, R.M.; Chuanjing, Xu; Allred, R.E.

    1994-05-01

    We use six-element arrays of 97-MHz ST-quartz surface acoustic wave (SAW) devices to detect changes in thin-film mass and mechanical properties resulting from sorption of analytes by films representing two new classes of chemical sensor interface: self-assembled monolayers (SAMs) and plasma-grafted films (PGFs). While these materials do not display exceptional chemical selectivity, various combinations of the 7 different SAMs and 8 PGFs examined to produce distinct response patterns for each of 13 analytes. The analytes include aliphatic, aromatic, and chlorinated hydrocarbons; alcohols; ketones; organophosphonates; and water. Evaluation of the SAW array data using multidimensional cluster analysis techniques show that each chemical species can be correctly identified 100% of the time over the 9%- to 49%-of-saturation range using data from many combinations of four or more films.

  1. Properties of SAW synchronous two-port resonators on GdCa?O(BO?)? crystal.

    PubMed

    Soluch, Waldemar

    2011-02-01

    Surface acoustic wave (SAW) synchronous two-port resonators were fabricated and measured on several orientations of the GdCa?O(BO?)? crystal. Resonance frequencies, insertion losses, and unloaded quality factors of the resonators, measured at room temperature, were in the ranges of about 432.3 to 437.5 MHz, 3.8 to 6.3 dB, and 6500 to 7500, respectively. The properties of this crystal, such as its lack of a phase transition up to its melting temperature of about 1500 C, a SAW temperature coefficient of frequency of about -80 ppm/ C, and good parameters of the resonators make the crystal attractive for high-temperature sensor applications. PMID:21342834

  2. Developments towards a surface acoustic wave (SAW) sensor for detecting volatiles and its evaluation system

    NASA Astrophysics Data System (ADS)

    Ali, Azam; Mohamed, K.; Ranford, S. L.; Zhang, H.

    2009-07-01

    This work presents developments towards sensors with a flexible information management system. Substrates used for engineering passive and wireless surface acoustic wave (SAW) devices with interactive materials were tested for detection of temperature, humidity, carbon dioxide and other volatiles associated with food exports. Testing of new interactive materials was carried out using quartz crystal microbalance (QCM) methods. In preparation for testing new interactive materials, SAW devices with dimensions of 44 mm2 were fabricated on quartz and lithium niobate (LiNbO3) substrates. To evaluate the devices, a system was developed using a data acquisition tool and human-machine interface developed with LABVIEW software to achieve inter-operability between sensing devices and controlled micro-environments.

  3. Wireless sensing using oscillator circuits locked to remote high-Q SAW resonators.

    PubMed

    Pohl, A; Ostermayer, G; Seifert, F

    1998-01-01

    This paper introduces a method of wireless read out of high Q surface acoustic wave (SAW) resonator sensors. The resonator is excited by a short RF pulse and decays after switching off the interrogating signal. In the measurement system, a gated phase locked loop (GPLL) locks to the resonance frequency of the SAW resonator within a few bursts. Then the frequency of the GPLL oscillator is synchronized to the resonance of the sensor and can be measured easily. The concept is intended to yield an alternative to interrogators with expensive signal processing. Considering the inherent limitations, the proposed system presents a low cost solution for temperature, force, torque, etc. measurements. We describe the sensors, the signals, and the implemented system. Results of temperature measurements using quartz resonators are presented, and merits and disadvantages are discussed. PMID:18244275

  4. Simulation research on cutting brittle optical material with diamond wire saw based on LS-DYNA

    NASA Astrophysics Data System (ADS)

    Wang, Jian; Liu, Jianbo; Xiao, Yonghao; Zhao, Shicao

    2014-08-01

    The quality of optical material cutting affects the efficiency and quality of follow-up polishing processing directly. Among various ways of cutting, the diamond wire saw cutting of fixed abrasive has advantages of narrow cutting seam, efficient cutting, high chip quality, little pollution to environment, ability to process bigger diameter workpiece, etc. So it has been used widely in optical material processing. In this paper, the coupled algorithm of FEM/SPH has been used to simulate deformation, fracture of brittle optical material in diamond grain cutting. The influence of workpiece feeding rate, cutting speed and cutting depth on the surface roughness are then analyzed in detail. Numerical simulation results show that the coupled algorithm efficiently explains the mechanism of material removal. From these results, we can not only determine optimum technology parameters for the manufacture of diamond wire saw, but also provide basis for improving the wire cutting efficiency and finished-product rate of optical material.

  5. Precision SAW filters for a large phased-array radar system

    NASA Astrophysics Data System (ADS)

    Haydl, W. H.; Sander, W.; Wirth, W.-D.

    1981-05-01

    The electronically steerable radar (ELRA) at the Forschungsinstitut fuer Funk und Mathematik is an experimental S-band phased-array radar system consisting of separate transmitting and receiving arrays employing several coherent and incoherent signal-processing and data-handling techniques, incorporating multiple beam and multifunction operation for target search and tracking, adaptive interference suppression, and target resolution. This paper deals with the development and application of two types of SAW filters for the IF amplifier channel of the receiving array. Compared to conventional filters with lumped elements, these filters have some important merits. By making use of a special tuning technique, the center frequencies of all filters were adjusted, resulting in an rms deviation of less than 1 kHz. One type of the SAW filters represents an almost ideal approach of realizing a matched filter for rectangular shaped pulses. The conformity of the frequency responses of several hundred filters improved the noise suppression capability of the system.

  6. Development of diamond-tipped chain saws for slot cutting in welded tuff

    SciTech Connect

    Zimmerman, R.M.; Finley, R.E.; Schuch, R.L.; Dodds, D.J.

    1987-12-31

    This paper describes the development and performance evaluations of two chain saws, one with a 1.1-m bar and the other with a 2.1-m bar, that were used to cut thin (less than 15 mm) planar slots in a jointed, welded tuff in G-tunnel on the Nevada Test Site as part of the Nevada Nuclear Waste Storage Investigations Project.

  7. Development of diamond-tipped chain saws for slot cutting in welded tuff

    SciTech Connect

    Zimmerman, R.M.; Finley, R.E.; Schuch, R.L.; Dodds, D.J.

    1987-12-31

    This paper describes the development and performance evaluations of two chain saws, one with a 1.1-m bar and the other with a 2.1-m bar, that were used to cut thin (less than 15 mm) planar slots in a jointed, welded tuff in G-Tunnel on the Nevada Test Site as part of the Nevada Nuclear Waste Storage Investigations Project. 6 refs., 3 figs., 2 tabs.

  8. Ladder-type SAW filters using thinned density of randomly distributed "hot" electrodes.

    PubMed

    Kim, Che-Uk; Balashov, Sergey M; Plessky, Victor P; Nam, Chang-Woo; Lee, Kyu-Chul

    2010-11-01

    A new method for the design of relatively narrowband ladder-type SAW filters is proposed. It consists of the thinning procedure and consecutive randomization of positions of the remaining transductive periods inside the IDT to suppress undesirable additional passbands. A 0.9% fractional bandwidth filter on LiTaO(3) 42-cut was designed and manufactured using the proposed approach. PMID:21041145

  9. Some Fundamental Limits on SAW RFID Tag Information Capacity and Collision Resolution

    NASA Technical Reports Server (NTRS)

    Barton, Richard J.

    2013-01-01

    In this paper, we apply results from multi-user information theory to study the limits of information capacity and collision resolution for SAW RFID tags. In particular, we derive bounds on the achievable data rate per tag as a function of fundamental parameters such as tag time-bandwidth product, tag signal-to-noise ratio (SNR), and number of tags in the environment. We also discuss the implications of these bounds for tag waveform design and tag interrogation efficiency

  10. Selective detection of elemental mercury vapor using a surface acoustic wave (SAW) sensor.

    PubMed

    Kabir, K M Mohibul; Sabri, Ylias M; Matthews, Glenn I; Jones, Lathe A; Ippolito, Samuel J; Bhargava, Suresh K

    2015-08-21

    The detection of elemental mercury (Hg(0)) within industrial processes is extremely important as it is the first major step in ensuring the efficient operation of implemented mercury removal technologies. In this study, a 131 MHz surface acoustic wave (SAW) delay line sensor with gold electrodes was tested towards Hg(0) vapor (24 to 365 ppbv) with/without the presence of ammonia (NH3) and humidity (H2O), as well as volatile organic compounds (VOCs) such as acetaldehyde (MeCHO), ethylmercaptan (EM), dimethyl disulfide (DMDS) and methyl ethyl ketone (MEK), which are all common interfering gas species that co-exist in many industrial applications requiring mercury monitoring. The developed sensor exhibited a detection limit of 0.7 ppbv and 4.85 ppbv at 35 and 55 C, respectively. Furthermore, a repeatability of 97% and selectivity of 92% in the presence of contaminant gases was exhibited by the sensor at the chosen operating temperature of 55 C. The response magnitude of the developed SAW sensor towards different concentrations of Hg(0) vapor fitted well with the Langmuir extension isotherm (otherwise known as loading ratio correlation (LRC)) which is in agreement with our basic finite element method (FEM) work where an LRC isotherm was observed for a simplified model of the SAW sensor responding to different Hg contents deposited on the Au based electrodes. Overall, the results indicate that the developed SAW sensor can be a potential solution for online selective detection of low concentrations of Hg(0) vapor found in industrial stack effluents. PMID:26065560

  11. Laboratory and field evaluation of a SAW microsensor array for measuring perchloroethylene in breath.

    PubMed

    Groves, William A; Achutan, Chandran

    2004-12-01

    This article describes the laboratory and field performance evaluation of a small prototype instrument employing an array of six polymer-coated surface acoustic wave (SAW) sensors and a thermal desorption preconcentration unit for rapid analysis of perchloroethylene in breath. Laboratory calibrations were performed using breath samples spiked with perchloroethylene to prepare calibration standards spanning a concentration range of 0.1-10 ppm. A sample volume of 250 mL was preconcentrated on 40 mg of Tenax GR at a flow rate of 100 mL/min, followed by a dry air purge and thermal desorption at a temperature of 200 degrees C. The resulting pulse of vapor was passed over the sensor array at a flow rate of 20 mL/min and sensor responses were recorded and displayed using a laptop computer. The total time per analysis was 4.5 min. SAW sensor responses were linear, and the instrument's limit of detection was estimated to be 50 ppb based on the criterion that four of the six sensors show a detectable response. Field performance was evaluated at a commercial dry-cleaning operation by comparing prototype instrument results for breath samples with those of a portable gas chromatograph (NIOSH 3704). Four breath samples were collected from a single subject over the course of the workday and analyzed using the portable gas chromatograph (GC) and SAW instruments. An additional seven spiked breath samples were prepared and analyzed so that a broader range of perchloroethylene concentrations could be examined. Linear regression analysis showed excellent agreement between prototype instrument and portable GC breath sample results with a correlation coefficient of 0.99 and a slope of 1.04. The average error for the prototype instrument over a perchloroethylene breath concentration range of 0.9-7.2 ppm was 2.6% relative to the portable GC. These results demonstrate the field capabilities of SAW microsensor arrays for rapid analysis of organic vapors in breath. PMID:15742707

  12. Pseudo-orthogonal frequency coded wireless SAW RFID temperature sensor tags.

    PubMed

    Saldanha, Nancy; Malocha, Donald C

    2012-08-01

    SAW sensors are ideal for various wireless, passive multi-sensor applications because they are small, rugged, radiation hard, and offer a wide range of material choices for operation over broad temperature ranges. The readable distance of a tag in a multi-sensor environment is dependent on the insertion loss of the device and the processing gain of the system. Single-frequency code division multiple access (CDMA) tags that are used in high-volume commercial applications must have universal coding schemes and large numbers of codes. The use of a large number of bits at the common center frequency to achieve sufficient code diversity in CDMA tags necessitates reflector banks with >30 dB loss. Orthogonal frequency coding is a spread-spectrum approach that employs frequency and time diversity to achieve enhanced tag properties. The use of orthogonal frequency coded (OFC) SAW tags reduces adjacent reflector interactions for low insertion loss, increased range, complex coding, and system processing gain. This work describes a SAW tag-sensor platform that reduces device loss by implementing long reflector banks with optimized spectral coding. This new pseudo-OFC (POFC) coding is defined and contrasted with the previously defined OFC coding scheme. Auto- and cross-correlation properties of the chips and their relation to reflectivity per strip and reflector length are discussed. Results at 250 MHz of 8-chip OFC and POFC SAW tags will be compared. The key parameters of insertion loss, cross-correlation, and autocorrelation of the two types of frequency-coded tags will be analyzed, contrasted, and discussed. It is shown that coded reflector banks can be achieved with near-zero loss and still maintain good coding properties. Experimental results and results predicted by the coupling of modes model are presented for varying reflector designs and codes. A prototype 915-MHz POFC sensor tag is used as a wireless temperature sensor and the results are shown. PMID:22899121

  13. Beveled osteotomies in lateral orbitotomy using a customized rotating bone saw for orbital neoplasms.

    PubMed

    Santiago, Maria Donna Damo; Tuano, Prospero Maria

    2015-06-01

    This study aims to develop a novel method of beveled osteotomy for lateral orbitotomy using a customized 21-mm stainless steel rotating saw in lateral orbitotomy and to evaluate the outcome of a novel beveled osteotomy in lateral orbitotomy. This article presents a case series (19 orbits from 18 patients) of lateral orbitotomies for excision biopsy of orbital neoplasms, over a 10-year period (from September 2001 to October 2011). It is a retrospective observational study. The surgeries were performed under the primary service of one surgeon (M. D. D. S.), the author of this study. All patients were treated via beveled osteotomies in lateral orbitotomy using a stainless steel, 21?mm diameter, customized rotating bone saw. Preoperative and postoperative measurements were tabulated and statistically analyzed. The case series demonstrated that beveled osteotomies in lateral orbitotomy using a stainless steel, 21?mm diameter, customized rotating bone saw was technically possible and provided access to lateral subperiorbital, peripheral, and central surgical spaces. The exposure was ample for excision biopsy of all neoplasms in this study. No patient needed the use of miniplate hardware in repositioning the lateral orbital wall nor complained of a palpable deformity of the lateral orbital wall. The wound healing was rapid, with minimal tissue distortion or scars. There were two patients who developed skin burns, but neither required a cosmetic surgery to correct scarring from the burn. It was concluded that the modified technique of beveled osteotomies in lateral orbitotomy provides excellent access to the lateral subperiorbital, peripheral and central surgical spaces. The exposure was adequate for excision biopsy of all neoplasms in this study. The technique promotes osseous union without the use of miniplate hardware. The use of a stainless steel 21?mm diameter customized rotating bone saw facilitated the successful outcome of the beveled technique. PMID:26000087

  14. Cell detachment and label-free cell sorting using modulated surface acoustic waves (SAWs) in droplet-based microfluidics.

    PubMed

    Bussonnire, Adrien; Miron, Yannick; Baudoin, Michal; Bou Matar, Olivier; Grandbois, Michel; Charette, Paul; Renaudin, Alan

    2014-09-21

    We present a droplet-based surface acoustic wave (SAW) system designed to viably detach biological cells from a surface and sort cell types based on differences in adhesion strength (adhesion contrast) without the need to label cells with molecular markers. The system uses modulated SAW to generate pulsatile flows in the droplets and efficiently detach the cells, thereby minimizing the SAW excitation power and exposure time. As a proof of principle, the system shows efficient sorting of HEK 293 from A7r5 cells based on adhesion contrast. Results are obtained in minutes with sorting purity and efficiency reaching 97% and 95%, respectively. PMID:25029952

  15. Surface morphology of ultrathin graphene oxide films obtained by the SAW atomization

    NASA Astrophysics Data System (ADS)

    Balachova, Olga V.; Balashov, Sergey M.; Costa, Carlos A. R.; Pavani Filho, A.

    2015-08-01

    Lately, graphene oxide (GO) thin films have attracted much attention: they can be used as humidity-sensitive coatings in the surface acoustic wave (SAW) sensors; being functionalized, they can be used in optoelectronic or biodevices, etc. In this research we study surface morphology of small-area thin GO films obtained on Si and quartz substrates by deposition of very small amounts of H2O-GO aerosols produced by the SAW atomizer. An important feature of this method is the ability to work with submicrovolumes of liquids during deposition that provides relatively good control over the film thickness and quality, in particular, minimization of the coffee ring effect. The obtained films were examined using AFM and electron microscopy. Image analysis showed that the films consist of GO sheets of different geometry and sizes and may form discrete or continuous coatings at the surface of the substrates with the minimum thickness of 1.0-1.8 nm which corresponds to one or two monolayers of GO. The thickness and quality of the deposited films depend on the parameters of the SAW atomization (number of atomized droplets, a volume of the initial droplet, etc.) and on sample surface preparation (activation in oxygen plasma). We discuss the structure of the obtained films, uniformity and the surface coverage as a function of parameters of the film deposition process and sample preparation. Qualitative analysis of adhesion of GO films is made by rinsing the samples in DI water and subsequent evaluation of morphology of the remained films.

  16. Application of the see-saw method to all refracting optical systems.

    PubMed

    Rosete-Aguilar, M

    1996-04-01

    The optical see-saw diagram is a method that describes image correction to third-order approximation over a finite field of view in rotationally symmetric systems that employ aspheric surfaces. The aim of this paper is to describe the correction of aberrations caused by plane surfaces in all refracting optical systems in terms of the see-saw diagram. A lens correction algorithm based on the see-saw method is described to correct analytically the Seidel aberrations, primary spherical aberration, coma, astigmatism, and distortion, in such systems. We then apply this lens correction algorithm to the design of equivalent configurations by aspherizing different surfaces of the system, and the high-order aberrations of the equivalent configurations are evaluated by means of transverse-ray-aberration plots. Results indicate that this method gives information on what the contribution must be to the third-order aberrations that each component should provide to the system to give a better balance of high-order aberrations. Examples of the lens correction algorithm applied to lenses with six refracting surfaces and working for both finite and infinite object conjugates are given. PMID:21085287

  17. Derotation of post-traumatic femoral deformities by closed intramedullary sawing.

    PubMed

    Stahl, Jens-Peter; Alt, Volker; Kraus, Ralf; Hoerbelt, Ruediger; Itoman, Moritoshi; Schnettler, Reinhard

    2006-02-01

    Different techniques and devices have been used for correction osteotomies of bones in patients with malalignments. The most frequently used technique for rotational deformities of the femur and tibia is open osteotomy with an oscillating saw and pre-drilled holes with all well-known drawbacks of open surgery. An intramedullary device with an adapted minimal-invasive surgical technique allows intramedullary osteotomy of the bone preserving the surrounding soft tissue. We performed femoral osteotomies with an intramedullary saw followed by static interlocking nailing in 14 patients with post-traumatic rotational deformity in the femur. Twelve patients had an external rotational deformity of the femur ranging between 26 and 63 degrees , one had an additional leg-shortening of about 4 cm. Two patients had internal rotational deformities. In two patients with delayed fracture healing union was achieved within one year without secondary surgery. Post-operative clinical assessment and CT-scans revealed good derotation results with deformities of less than 4 degrees in all cases. No device-related complications were observed. Therefore, we conclude that "closed" osteotomy with an intramedullary saw is a minimal-invasive, safe and reliable option for derotation procedures in the femur. PMID:16243332

  18. Recent developments on surface acoustic wave (SAW) sensors for harsh conditions

    NASA Astrophysics Data System (ADS)

    Schiopu, Paul; Chilibon, Irinela; Grosu, Neculai; Craciun, Alexandru

    2015-02-01

    The results of research into Surface Acoustic Waves (SAW) devices have been recognized for their efficiency and versatility in the electrical signals processing. Actual progress in the industrial application of piezoelectric materials such as Lithium Niobate (LiNbO3), Langasite (LGS), Lanthanum-Gallium Silicate La3Ga5SiO14 and Gallium Orthophosphate (GaPO4), allows the manufacturing of devices with piezoelectric performances, which overcome the limits obtained with quartz crystals. The single crystal materials have a long term high stability - near to infinite - and moreover, some of these have an excellent behavior with temperature variation. Today, GaPO4 with its properties is by far the best suited piezoelectric material to be used in sensor applications for machine monitoring and pressure measurements, at high temperatures. SAW micro devices based on GaPO4 operate at temperatures of up to 8000C. For a particular case, of harsh-environment applications, additional challenges need to be overcome, relating to substrate integrity and operation, thin film electrode fabrication, device packaging, and sensor interrogation. This paper reviews the novel progres in the area of (SAW) sensors for harsh conditions.

  19. Maximum measurement range and accuracy of SAW reflective delay line sensors.

    PubMed

    Zheng, Zehua; Han, Tao; Qin, Peng

    2015-01-01

    In a surface acoustic wave (SAW) wireless sensor with a reflective delay line structure, three reflectors are often used to eliminate 2? ambiguity of phase measurement. The maximum range of the measured parameter and the maximum accuracy have recently been attracting much research attention. In this paper, an analytical formula for all the factors influencing the measurement range and accuracy of the delay line SAW sensor are deduced for the first time. The factors include: the sensor sensitivity, the topology of the delay line, the available wireless bandwidth and the allowed maximum phase measuring error of the reading system, which is easier to retrieve and more fully describes the possible noises than SNR. Additionally, many designers believe that increasing the reflector could improve accuracy continuously or realize multi-resolution measurement. However, they ignore some certain criteria that the reflector location must satisfy. The reachable maximum accuracy by every increase of a reflector is also presented. A SAW temperature sensor system using 128 YX-LiNbO3 is designed to verify the above theoretical analysis. PMID:26492251

  20. Maximum Measurement Range and Accuracy of SAW Reflective Delay Line Sensors

    PubMed Central

    Zheng, Zehua; Han, Tao; Qin, Peng

    2015-01-01

    In a surface acoustic wave (SAW) wireless sensor with a reflective delay line structure, three reflectors are often used to eliminate 2? ambiguity of phase measurement. The maximum range of the measured parameter and the maximum accuracy have recently been attracting much research attention. In this paper, an analytical formula for all the factors influencing the measurement range and accuracy of the delay line SAW sensor are deduced for the first time. The factors include: the sensor sensitivity, the topology of the delay line, the available wireless bandwidth and the allowed maximum phase measuring error of the reading system, which is easier to retrieve and more fully describes the possible noises than SNR. Additionally, many designers believe that increasing the reflector could improve accuracy continuously or realize multi-resolution measurement. However, they ignore some certain criteria that the reflector location must satisfy. The reachable maximum accuracy by every increase of a reflector is also presented. A SAW temperature sensor system using 128 YX-LiNbO3 is designed to verify the above theoretical analysis. PMID:26492251

  1. Advances in SXFA-coated SAW chemical sensors for organophosphorous compound detection.

    PubMed

    Wang, Wen; He, Shitang; Li, Shunzhou; Liu, Minghua; Pan, Yong

    2011-01-01

    A polymer-coated surface acoustic wave (SAW)-based chemical sensor for organophosphorous compound sensing at extremely low concentrations was developed, in which a dual-delay-line oscillator coated with fluoroalcoholpolysiloxane (SXFA) acted as the sensor element. Response mechanism analysis was performed on the SXFA-coated chemical sensor, resulting in the optimal design parameters. The shear modulus of the SXFA, which is the key parameter for theoretical simulation, was extracted experimentally. New designs were done on the SAW devices to decrease the insertion loss. Referring to the new phase modulation approach, superior short-term frequency stability (2 Hz in seconds) was achieved from the SAW oscillator using the fabricated 300 MHz delay line as the feedback element. In the sensor experiment on dimethylmethylphosphonate (DMMP) detection, the fabricated SXFA-coated chemical sensor exhibited an excellent threshold detection limit up to 0.004 mg/m(3) (0.7 ppb) and good sensitivity (?485 Hz/mg/m(3) for a DMMP concentration of 2?14 mg/m(3)). PMID:22319366

  2. Advances in SXFA-Coated SAW Chemical Sensors for Organophosphorous Compound Detection

    PubMed Central

    Wang, Wen; He, Shitang; Li, Shunzhou; Liu, Minghua; Pan, Yong

    2011-01-01

    A polymer-coated surface acoustic wave (SAW)-based chemical sensor for organophosphorous compound sensing at extremely low concentrations was developed, in which a dual-delay-line oscillator coated with fluoroalcoholpolysiloxane (SXFA) acted as the sensor element. Response mechanism analysis was performed on the SXFA-coated chemical sensor, resulting in the optimal design parameters. The shear modulus of the SXFA, which is the key parameter for theoretical simulation, was extracted experimentally. New designs were done on the SAW devices to decrease the insertion loss. Referring to the new phase modulation approach, superior short-term frequency stability (2 Hz in seconds) was achieved from the SAW oscillator using the fabricated 300 MHz delay line as the feedback element. In the sensor experiment on dimethylmethylphosphonate (DMMP) detection, the fabricated SXFA-coated chemical sensor exhibited an excellent threshold detection limit up to 0.004 mg/m3 (0.7 ppb) and good sensitivity (?485 Hz/mg/m3 for a DMMP concentration of 2?14 mg/m3). PMID:22319366

  3. Development of a Room Temperature SAW Methane Gas Sensor Incorporating a Supramolecular Cryptophane A Coating

    PubMed Central

    Wang, Wen; Hu, Haoliang; Liu, Xinlu; He, Shitang; Pan, Yong; Zhang, Caihong; Dong, Chuan

    2016-01-01

    A new room temperature supra-molecular cryptophane A (CrypA)-coated surface acoustic wave (SAW) sensor for sensing methane gas is presented. The sensor is composed of differential resonator-oscillators, a supra-molecular CrypA coated along the acoustic propagation path, and a frequency signal acquisition module (FSAM). A two-port SAW resonator configuration with low insertion loss, single resonation mode, and high quality factor was designed on a temperature-compensated ST-X quartz substrate, and as the feedback of the differntial oscillators. Prior to development, the coupling of modes (COM) simulation was conducted to predict the device performance. The supramolecular CrypA was synthesized from vanillyl alcohol using a double trimerisation method and deposited onto the SAW propagation path of the sensing resonators via different film deposition methods. Experiential results indicate the CrypA-coated sensor made using a dropping method exhibits higher sensor response compared to the unit prepared by the spinning approach because of the obviously larger surface roughness. Fast response and excellent repeatability were observed in gas sensing experiments, and the estimated detection limit and measured sensitivity are ~0.05% and ~204 Hz/%, respectively. PMID:26751450

  4. Development of a Room Temperature SAW Methane Gas Sensor Incorporating a Supramolecular Cryptophane A Coating.

    PubMed

    Wang, Wen; Hu, Haoliang; Liu, Xinlu; He, Shitang; Pan, Yong; Zhang, Caihong; Dong, Chuan

    2016-01-01

    A new room temperature supra-molecular cryptophane A (CrypA)-coated surface acoustic wave (SAW) sensor for sensing methane gas is presented. The sensor is composed of differential resonator-oscillators, a supra-molecular CrypA coated along the acoustic propagation path, and a frequency signal acquisition module (FSAM). A two-port SAW resonator configuration with low insertion loss, single resonation mode, and high quality factor was designed on a temperature-compensated ST-X quartz substrate, and as the feedback of the differntial oscillators. Prior to development, the coupling of modes (COM) simulation was conducted to predict the device performance. The supramolecular CrypA was synthesized from vanillyl alcohol using a double trimerisation method and deposited onto the SAW propagation path of the sensing resonators via different film deposition methods. Experiential results indicate the CrypA-coated sensor made using a dropping method exhibits higher sensor response compared to the unit prepared by the spinning approach because of the obviously larger surface roughness. Fast response and excellent repeatability were observed in gas sensing experiments, and the estimated detection limit and measured sensitivity are ~0.05% and ~204 Hz/%, respectively. PMID:26751450

  5. Evaluation of Relative Sensitivity of SAW and Flexural Plate Wave Devices for Atmospheric Sensing

    NASA Technical Reports Server (NTRS)

    White, Richard M.; Black, Justin; Chen, Bryan

    1998-01-01

    The objective of this project is to evaluate the suitability of the ultrasonic flexural plate wave (FPW) device as the detector in a gas chromatograph (GC). Of particular interest is the detection of nitrous oxide (N2O). From experimental results we conclude analyte detection is achieved through two mechanisms: changes in gas density, and mass loading of the device membrane due to the sorption of gas molecules. Reducing the dead volume of the FPW chamber increased the FPW response. A comparison of the FPW response to that of the surface acoustic wave (SAW) detector provided with the GC (made by MSI, Microsensor Technologies, Inc.), shows that for unseparated N2O in N2, the FPW exhibits a sensitivity that is at least 550 times greater than that of the SAW device. A Porapak Q column was found to separate N2O from its carrier gas, N2 or He. With the Porapak Q column, a coated FPW detected 1 ppm N2O in N2 or He, with a response magnitude of 7 Hz. A coated SAW exhibited a response of 25 Hz to pure N2O. The minimal detectable N2O concentrations of the sensors were not evaluated.

  6. Thin, High Lifetime Silicon Wafers with No Sawing; Re-crystallization in a Thin Film Capsule

    SciTech Connect

    Emanuel Sachs Tonio Buonassisi

    2013-01-16

    The project fits within the area of renewable energy called photovoltaics (PV), or the generation of electricity directly from sunlight using semiconductor devices. PV has the greatest potential of any renewable energy technology. The vast majority of photovoltaic modules are made on crystalline silicon wafers and these wafers accounts for the largest fraction of the cost of a photovoltaic module. Thus, a method of making high quality, low cost wafers would be extremely beneficial to the PV industry The industry standard technology creates wafers by casting an ingot and then sawing wafers from the ingot. Sawing rendered half of the highly refined silicon feedstock as un-reclaimable dust. Being a brittle material, the sawing is actually a type of grinding operation which is costly both in terms of capital equipment and in terms of consumables costs. The consumables costs associated with the wire sawing technology are particularly burdensome and include the cost of the wire itself (continuously fed, one time use), the abrasive particles, and, waste disposal. The goal of this project was to make wafers directly from molten silicon with no sawing required. The fundamental concept was to create a very low cost (but low quality) wafer of the desired shape and size and then to improve the quality of the wafer by a specialized thermal treatment (called re-crystallization). Others have attempted to create silicon sheet by recrystallization with varying degrees of success. Key among the difficulties encountered by others were: a) difficulty in maintaining the physical shape of the sheet during the recrystallization process and b) difficulty in maintaining the cleanliness of the sheet during recrystallization. Our method solved both of these challenges by encapsulating the preform wafer in a protective capsule prior to recrystallization (see below). The recrystallization method developed in this work was extremely effective at maintaining the shape and the cleanliness of the wafer. In addition, it was found to be suitable for growing very large crystals. The equipment used was simple and inexpensive to operate. Reasonable solar cells were fabricated on re-crystallized material.

  7. Detection, Identification, Location, and Remote Sensing Using SAW RFID Sensor Tags

    NASA Technical Reports Server (NTRS)

    Barton, Richard J.; Kennedy, Timothy F.; Williams, Robert M.; Fink, Patrick W.; Ngo, Phong H.

    2009-01-01

    The Electromagnetic Systems Branch (EV4) of the Avionic Systems Division at NASA Johnson Space Center in Houston, TX is studying the utility of surface acoustic wave (SAW) radiofrequency identification (RFID) tags for multiple wireless applications including detection, identification, tracking, and remote sensing of objects on the lunar surface, monitoring of environmental test facilities, structural shape and health monitoring, and nondestructive test and evaluation of assets. For all of these applications, it is anticipated that the system utilized to interrogate the SAW RFID tags may need to operate at fairly long range and in the presence of considerable multipath and multiple-access interference. Towards that end, EV4 is developing a prototype SAW RFID wireless interrogation system for use in such environments called the Passive Adaptive RFID Sensor Equipment (PARSED) system. The system utilizes a digitally beam-formed planar receiving antenna array to extend range and provide direction-of-arrival information coupled with an approximate maximum-likelihood signal processing algorithm to provide near-optimal estimation of both range and temperature. The system is capable of forming a large number of beams within the field of view and resolving the information from several tags within each beam. The combination of both spatial and waveform discrimination provides the capability to track and monitor telemetry from a large number of objects appearing simultaneously within the field of view of the receiving array. In this paper, we will consider the application of the PARSEQ system to the problem of simultaneous detection, identification, localization, and temperature estimation for multiple objects. We will summarize the overall design of the PARSEQ system and present a detailed description of the design and performance of the signal detection and estimation algorithms incorporated in the system. The system is currently configured only to measure temperature (jointly with range and tag ID), but future versions will be revised to measure parameters other than temperature as SAW tags capable of interfacing with external sensors become available. It is anticipated that the estimation of arbitrary parameters measured using SAW-based sensors will be based on techniques very similar to the joint range and temperature estimation techniques described in this paper.

  8. Deep-UV sensors based on SAW oscillators using low-temperature-grown AlN films on sapphires.

    PubMed

    Laksana, Chipta; Chen, Meei-Ru; Liang, Yen; Tzou, An-Jyeg; Kao, Hui-Ling; Jeng, Erik; Chen, Jyh; Chen, Hou-Guang; Jian, Sheng-Rui

    2011-08-01

    High-quality epitaxial AlN films were deposited on sapphire substrates at low growth temperature using a helicon sputtering system. SAW filters fabricated on the AlN films exhibited excellent characteristics, with center frequency of 354.2 MHz, which corresponds to a phase velocity of 5667 m/s. An oscillator fabricated using AlN-based SAW devices is presented and applied to deep-UV light detection. A frequency downshift of about 43 KHz was observed when the surface of SAW device was illuminated by a UV source with dominant wavelength of around 200 nm. The results indicate the feasibility of developing remote sensors for deep-UV measurement using AlN-based SAW oscillators. PMID:21859589

  9. INTERNATIONAL UNION OF OPERATING ENGINEERS NATIONAL HAZMAT PROGRAM - ADAMANT CIRCULAR SAW OENHP{number_sign}: 2001-05, VERSION A

    SciTech Connect

    Unknown

    2002-01-01

    Florida International University's (FIU) Hemispheric Center for Environmental Technology (HCET) evaluated five saws for their effectiveness in cutting up specially prepared fiberglass-reinforced plywood crates. These crates were built as surrogates for crates that presently hold radioactive contaminated glove boxes at the Department of Energy's (DOE) Los Alamos facility. The Adamant circular saw was assessed on August 14, 2001. During the FIU test of efficacy, a team from the Operating Engineers National Hazmat Program (OENHP) evaluated the occupational safety and health issues associated with this technology. The Adamant was only used during a limited ''test'' on a regular plywood crate due to safety considerations of the tool for this application. The Adamant circular saw, a counter-rotating twin-cutter, constructed with blades that work differently than conventional cutting wheels with twin blades, each rotating in opposite directions. It is used to cut wood and metals. Each blade is approximately 8 3/4 inches in diameter with a maximum cutting depth of 2 1/2 inches. The machine has two rotation speeds: 1,900 and 2,900 rotations per minute (rpm). The saw is operated with an interlocked, guarded trigger switch located at the end of the saw opposite the cutting blades. To operate the saw, the safety interlock must be depressed prior to powering the saw with the trigger control. The saw is supported by a handle at the front of the saw near the cutting blades. The top part of the blades is guarded near the handle, with approximately three-fourths of the face of the blades exposed. The Adamant circular saw is an innovative technology used to cut metals and wood. Its safety features include: interlocking switch for powering the saw, overload indicator and shutoff, and an electronic brake that stops the engine immediately when the start button is released. The top part of the blades is guarded near the motor. With approximately three-fourths of the face of the blades open, the operator is exposed to the potential risk of serious and minor cuts and abrasions when using and handling the saw. There is also potential for damage to the blades if the saw is not stored properly. Without guarding on the lower part of the blades, these can be damaged if the saw is dropped or rested on the cutting blades. Based upon the industrial hygiene sampling conducted for the other four saws demonstrated at FIU, noise levels, nuisance dust, and airborne fiberglass may be a problem when using this technology for the cutting of fiberglass-reinforced plywood crates. No industrial hygiene sampling was conducted while the Adamant saw was in use. Engineering controls should be used to eliminate these problems whenever possible. Where this is not possible, administrative controls, training, and proper personal protective equipment (PPE) should be used. Respirators should be used if engineering controls do not sufficiently control the dust or fiberglass generated. Respirators should be equipped with an organic vapor and acid gas cartridge with High Efficiency Particulate Air (HEPA) filter, since during the demonstration, the workers complained of an odd smell, which may have been the breakdown of the fiberglass.

  10. A surface acoustic wave (SAW)-enhanced grating-coupling phase-interrogation surface plasmon resonance (SPR) microfluidic biosensor.

    PubMed

    Sonato, A; Agostini, M; Ruffato, G; Gazzola, E; Liuni, D; Greco, G; Travagliati, M; Cecchini, M; Romanato, F

    2016-03-23

    A surface acoustic wave (SAW)-enhanced, surface plasmon resonance (SPR) microfluidic biosensor in which SAW-induced mixing and phase-interrogation grating-coupling SPR are combined in a single lithium niobate lab-on-a-chip is demonstrated. Thiol-polyethylene glycol adsorption and avidin/biotin binding kinetics were monitored by exploiting the high sensitivity of grating-coupling SPR under azimuthal control. A time saturation binding kinetics reduction of 82% and 24% for polyethylene and avidin adsorption was obtained, respectively, due to the fluid mixing enhancement by means of the SAW-generated chaotic advection. These results represent the first implementation of a nanostructured SAW-SPR microfluidic biochip capable of significantly improving the molecule binding kinetics on a single, portable device. In addition, the biochip here proposed is suitable for a great variety of biosensing applications. PMID:26932784

  11. Piezoelectric shunt damping of a circular saw blade with autonomous power supply for noise and vibration reduction

    NASA Astrophysics Data System (ADS)

    Pohl, Martin; Rose, Michael

    2016-01-01

    Circular saws are widespread tools for machining metal, wood or even ceramics. Due to the thin blade and excitation by the workpiece contact of the cutting edges, circular saws are prone to vibration and intense noise emission. Damping the blade will lower the hearing protection requirements of the users and possibly increase precision. Therefore a new damping concept for circular saw blades is presented in this paper. It is based on negative capacitance shunted piezoelectric transducers which are applied to the saw blade core. The required energy for the electronics is harvested from the rotation by a generator, so that no change of the machine tool is required. All components are integrated into an autonomous saw tool. Finally, the system is experimentally investigated without rotation, in idling and in cutting condition in a circular saw test stand in the Institute for Machine Tools and Production Engineering (IWF) at TU Braunschweig. The experimental investigation shows a good reduction of the vibration amplitude over a wide frequency range in the non-rotating condition. When rotating, the damping effect is lower and limited to some narrow frequency bands. The proposed reason for the reduced damping effect in rotating condition consists in the saturation of the electronic circuits due to the limited supply voltage capabilities.

  12. iSAW: Integrating Structure, Actors, and Water to study socio-hydro-ecological systems

    NASA Astrophysics Data System (ADS)

    Hale, Rebecca L.; Armstrong, Andrea; Baker, Michelle A.; Bedingfield, Sean; Betts, David; Buahin, Caleb; Buchert, Martin; Crowl, Todd; Dupont, R. Ryan; Ehleringer, James R.; Endter-Wada, Joanna; Flint, Courtney; Grant, Jacqualine; Hinners, Sarah; Horsburgh, Jeffery S.; Jackson-Smith, Douglas; Jones, Amber S.; Licon, Carlos; Null, Sarah E.; Odame, Augustina; Pataki, Diane E.; Rosenberg, David; Runburg, Madlyn; Stoker, Philip; Strong, Courtenay

    2015-03-01

    Urbanization, climate, and ecosystem change represent major challenges for managing water resources. Although water systems are complex, a need exists for a generalized representation of these systems to identify important components and linkages to guide scientific inquiry and aid water management. We developed an integrated Structure-Actor-Water framework (iSAW) to facilitate the understanding of and transitions to sustainable water systems. Our goal was to produce an interdisciplinary framework for water resources research that could address management challenges across scales (e.g., plot to region) and domains (e.g., water supply and quality, transitioning, and urban landscapes). The framework was designed to be generalizable across all human-environment systems, yet with sufficient detail and flexibility to be customized to specific cases. iSAW includes three major components: structure (natural, built, and social), actors (individual and organizational), and water (quality and quantity). Key linkages among these components include: (1) ecological/hydrologic processes, (2) ecosystem/geomorphic feedbacks, (3) planning, design, and policy, (4) perceptions, information, and experience, (5) resource access and risk, and (6) operational water use and management. We illustrate the flexibility and utility of the iSAW framework by applying it to two research and management problems: understanding urban water supply and demand in a changing climate and expanding use of green storm water infrastructure in a semi-arid environment. The applications demonstrate that a generalized conceptual model can identify important components and linkages in complex and diverse water systems and facilitate communication about those systems among researchers from diverse disciplines.

  13. High-energy x-ray optics with silicon saw-tooth refractive lenses.

    SciTech Connect

    Shastri, S. D.; Almer, J. A.; Ribbing, C. R.; Cederstrom, B. C.; X-Ray Science Division; Uppsala Univ.; Royal Inst. of Tech.

    2007-01-01

    Silicon saw-tooth refractive lenses have been in successful use for vertical focusing and collimation of high-energy X-rays (50-100 keV) at the 1-ID undulator beamline of the Advanced Photon Source. In addition to presenting an effectively parabolic thickness profile, as required for aberration-free refractive optics, these devices allow high transmission and continuous tunability in photon energy and focal length. Furthermore, the use of a single-crystal material (i.e. Si) minimizes small-angle scattering background. The focusing performance of such saw-tooth lenses, used in conjunction with the 1-ID beamline's bent double-Laue monochromator, is presented for both short ({approx}1:0.02) and long ({approx}1:0.6) focal-length geometries, giving line-foci in the 2 {micro}m-25 {micro}m width range with 81 keV X-rays. In addition, a compound focusing scheme was tested whereby the radiation intercepted by a distant short-focal-length lens is increased by having it receive a collimated beam from a nearer (upstream) lens. The collimation capabilities of Si saw-tooth lenses are also exploited to deliver enhanced throughput of a subsequently placed small-angular-acceptance high-energy-resolution post-monochromator in the 50-80 keV range. The successful use of such lenses in all these configurations establishes an important detail, that the pre-monochromator, despite being comprised of vertically reflecting bent Laue geometry crystals, can be brilliance-preserving to a very high degree.

  14. Achievable Performance and Effective Interrogator Design for SAW RFID Sensor Tags

    NASA Technical Reports Server (NTRS)

    Barton, Richard J.

    2011-01-01

    For many NASA missions, remote sensing is a critical application that supports activities such as environmental monitoring, planetary science, structural shape and health monitoring, non-destructive evaluation, etc. The utility of the remote sensing devices themselves is greatly increased if they are passive that is, they do not require any on-board power supply such as batteries and if they can be identified uniquely during the sensor interrogation process. Additional passive sensor characteristics that enable greater utilization in space applications are small size and weight, long read ranges with low interrogator power, ruggedness, and operability in extreme environments (vacuum, extreme high/low temperature, high radiation, etc.) In this paper, we consider one very promising passive sensor technology, called surface acoustic wave (SAW) radio-frequency identification (RFID), that satisfies all of these criteria. Although SAW RFID tags have great potential for use in numerous space-based remote sensing applications, the limited collision resolution capability of current generation tags limits the performance in a cluttered sensing environment. That is, as more SAW-based sensors are added to the environment, numerous tag responses are superimposed at the receiver and decoding all or even a subset of the telemetry becomes increasingly difficult. Background clutter generated by reflectors other than the sensors themselves is also a problem, as is multipath interference and signal distortion, but the limiting factor in many remote sensing applications can be expected to be tag mutual interference. This problem may be greatly mitigated by proper design of the SAW tag waveform, but that remains an open research problem, and in the meantime, several other related questions remain to be answered including: What are the fundamental relationships between tag parameters such as bit-rate, time-bandwidth-product, SNR, and achievable collision resolution? What are the differences in optimal or near-optimal interrogator designs between noise-limited environments and interference-limited environments? What are the performance characteristics of different interrogator designs in term of parameters such as transmitter power level, range, and number of interfering tags? In this paper, we present the results of a research effort aimed at providing at least partial answers to all of these questions.

  15. Numerical study of the spectral 3-D green's function singularities for piezoelectric SAW components.

    PubMed

    Durn, Mario; Ndlec, Jean-Claude; Ossandn, Sebastin

    2005-12-01

    This article deals with the numerical study of the singularities appearing in the spectral 3-D Green's function associated with the piezoelectric surface acoustic wave components (so-called SAW components). These electrical units are currently used today in several devices produced by the telecommunications industry (radio, TV, radar, and digital telecommunication systems). The need to improve their performance has motivated engineers and researchers to use mathematical modeling intensively, in particular the integral equations technique here used, which requires the computing of the associated Green's function and the study of its properties. PMID:16463506

  16. Self-avoiding-walks (SAW's) on diluted lattices, a Monte Carlo analysis

    NASA Astrophysics Data System (ADS)

    Kremer, Kurt

    1981-06-01

    A Monte Carlo study of SAW's on a diluted diamond lattice is presented. We find that the exponent v does not change by dilution, v?0.59 as in the undiluted case, in contrast to the original conclusion of Chakrabarti and Kertsz. This result cannot be understood by the Harris criterion. At the percolation concentration p c of the lattice we find a higher exponent v pc ?2/3. A scaling form of the crossover between these exponents near p c is proposed and found to be consistent with the Monte Carlo results.

  17. Proposal for generalised supersymmetry Les Houches Accord for see-saw models and PDG numbering scheme

    NASA Astrophysics Data System (ADS)

    Basso, L.; Belyaev, A.; Chowdhury, D.; Hirsch, M.; Khalil, S.; Moretti, S.; O'Leary, B.; Porod, W.; Staub, F.

    2013-03-01

    The SUSY Les Houches Accord (SLHA) 2 extended the first SLHA to include various generalisations of the Minimal Supersymmetric Standard Model (MSSM) as well as its simplest next-to-minimal version. Here, we propose further extensions to it, to include the most general and well-established see-saw descriptions (types I/II/III, inverse, and linear) in both an effective and a simple gauged extension of the MSSM framework. In addition, we generalise the PDG numbering scheme to reflect the properties of the particles.

  18. Safety and security monitoring of dams using nano-micromachined-based surface acoustic wave (SAW) sensors

    NASA Astrophysics Data System (ADS)

    Ross, Wayne, Jr.; Saafi, Mohamed; Romine, Peter; Xiao, Zhigang; Pett, Dave

    2006-03-01

    Concerns about the safety of concrete dams have increased during recent years, partly because the population at risk in locations downstream of major dams continues to expand and also because these old dams are experiencing long-term damage and the seismic design concepts used to build them were inadequate. Reliable techniques for continuous monitoring of certain key parameters affecting the dams' integrity are currently nonexistent and this is because of the lack of sensing technology capable to function in a hostile environment such as low temperatures and high moisture level. This paper presents new low cost, passive and wireless micro-machined SAW-based sensors to monitor the safety and security of dams. These SAW sensors are composed of MEMS transducers, Nano-polymer actuators and an antenna, and are deposited on a thin film substrate. The sensors are passive, do not require power on-board and can be interrogated wireless using a radar. When embedded into concrete dams, the devices will be able to detect and locate internal cracks and measure certain key parameters affecting the durability of dams such as temperature, moisture, pH, chloride and carbon dioxide.

  19. Development of flexible SAW sensors for non-destructive testing of structure

    NASA Astrophysics Data System (ADS)

    Takpara, R.; Duquennoy, M.; Courtois, C.; Gonon, M.; Ouaftouh, M.; Martic, G.; Rguiti, M.; Jenot, F.; Seronveaux, L.; Pelegris, C.

    2016-02-01

    In order to accurately examine structures surfaces, it is interesting to use surface SAW (Surface Acoustic Wave). Such waves are well suited for example to detect early emerging cracks or to test the quality of a coating. In addition, when coatings are thin or when emergent cracks are precocious, it is necessary to excite surface waves beyond 10MHz. Finally, when structures are not flat, it makes sense to have flexible or conformable sensors for their characterization. To address this problem, we propose to develop SAW type of interdigital sensors (or IDT for InterDigital Transducer), based on flexible piezoelectric plates. Initially, in order to optimize these sensors, we modeled the behavior of these sensors and identified the optimum characteristic sizes. In particular, the thickness of the piezoelectric plate and the width of the interdigital electrodes have been studied. Secondly, we made composites based on barium titanate foams in order to have flexible piezoelectric plates and to carry out thereafter sensors. Then, we studied several techniques in order to optimize the interdigitated electrodes deposition on this type of material. One of the difficulties concerns the fineness of these electrodes because the ratio between the length (typically several millimeters) and the width (a few tens of micrometers) of electrodes is very high. Finally, mechanical, electrical and acoustical characterizations of the sensors deposited on aluminum substrates were able to show the quality of our achievement.

  20. SAW-based fluid atomization using mass-producible chip devices.

    PubMed

    Winkler, A; Harazim, S M; Menzel, S B; Schmidt, H

    2015-09-21

    Surface acoustic wave (SAW)-based fluid atomizers are ideally suited to generate micrometer-sized droplets without any moving parts or nozzles. Versatile application fields can be found for instance in biomedical, aerosol or thin film technology, including medical inhalators or particle deposition for advanced surface treatment. Such atomizers also show great potential for on-chip integration and can lead to economic production of hand-held and even disposable devices, with either a single functionality or integrated in more complex superior systems. However, this potential was limited in the past by fluid supply mechanisms inadequate for mass production, accuracy and reliability. In this work, we briefly discuss existing fluid supply methods and demonstrate a straightforward new approach suited for reliable and cost-effective mass-scale manufacturing of SAW atomizer chips. Our approach is based on a fluid supply at the boundary of the acoustic beam via SU-8 microchannels produced by a novel one-layer/double-exposure photolithography method. Using this technique, we demonstrate precise and stable fluid atomization with almost ideal aerosol plume geometry from a dynamically stabilized thin fluid film. Additionally, we demonstrate the possibility of in situ altering the droplet size distribution by controlling the amount of fluid available in the active region of the chip. PMID:26262577

  1. Highly focused high-frequency travelling surface acoustic waves (SAW) for rapid single-particle sorting.

    PubMed

    Collins, David J; Neild, Adrian; Ai, Ye

    2016-01-26

    High-speed sorting is an essential process in a number of clinical and research applications, where single cells, droplets and particles are segregated based on their properties in a continuous flow. With recent developments in the field of microscale actuation, there is increasing interest in replicating the functions available to conventional fluorescence activated cell sorting (FACS) flow cytometry in integrated on-chip systems, which have substantial advantages in cost and portability. Surface acoustic wave (SAW) devices are ideal for many acoustofluidic applications, and have been used to perform such sorting at rates on the order of kHz. Essential to the accuracy of this sorting, however, is the dimensions of the region over which sorting occurs, where a smaller sorting region can largely avoid inaccurate sorting across a range of sample concentrations. Here we demonstrate the use of flow focusing and a highly focused SAW generated by a high-frequency (386 MHz), 10 ?m wavelength set of focused interdigital transducers (FIDTs) on a piezoelectric lithium niobate substrate, yielding an effective sorting region only ~25 ?m wide, with sub-millisecond pulses generated at up to kHz rates. Furthermore, because of the use of high frequencies, actuation of particles as small as 2 ?m can be realized. Such devices represent a substantial step forward in the evolution of highly localized forces for lab-on-a-chip microfluidic applications. PMID:26646200

  2. Exotic see-saw mechanism for neutrinos and leptogenesis in a Pati-Salam model

    NASA Astrophysics Data System (ADS)

    Addazi, Andrea; Bianchi, Massimo; Ricciardi, Giulia

    2016-02-01

    We discuss non-perturbative corrections to the neutrino sector, in the context of a D-brane Pati-Salam-like model, that can be obtained as a simple alternative to SO(10) GUT's in theories with open and unoriented strings. In such D-brane models, exotic stringy instantons can correct the right-handed neutrino mass matrix in a calculable way, thus affecting mass hierarchies and modifying the see-saw mechanism to what we name exotic see-saw. For a wide range of parameters, a compact spectrum of right-handed neutrino masses can occur that gives rise to a predictive scenario for low energy observables. This model also provides a viable mechanism for Baryon Asymmetry in the Universe (BAU) through leptogenesis. Finally, a Majorana mass for the neutron is naturally predicted in the model, leading to potentially testable neutron-antineutron oscillations. Combined measurements in neutrino and neutron-antineutron sectors could provide precious informations on physics at the quantum gravity scale.

  3. Polymer coating behavior of Rayleigh-SAW resonators with gold electrode structure for gas sensor applications.

    PubMed

    Avramov, Ivan D; Lnge, Kerstin; Rupp, Swen; Rapp, Bastian; Rapp, Michael

    2007-01-01

    Results from systematic polymer coating experiments on surface acoustic wave (SAW) resonators and coupled resonator filters (CRF) on ST-cut quartz with a corrosion-proof electrode structure entirely made of gold (Au) are presented and compared with data from similar SAW devices using aluminium (Al) electrodes. The recently developed Au devices are intended to replace their earlier Al counterparts in sensor systems operating in highly reactive chemical gas environments. Solid parylene C and soft poly[chlorotrifluoroethylene-co-vinylidene fluoride] (PCFV) polymer films are deposited under identical conditions onto the surface of Al and Au devices. The electrical performance of the Parylene C coated devices is monitored online during film deposition. The PCVF coated devices are evaluated after film deposition. The experimental data show that the Au devices can stand up to 40% thicker solid films for the same amount of loss increase than the Al devices and retain better resonance and phase characteristics. The frequency sensitivities of Au and Al devices to parylene C deposition are nearly identical. After coating with soft PCFV sensing film, the Au devices provide up to two times higher gas sensitivity when probed with cooling agent, octane, or tetrachloroethylene. PMID:17225810

  4. A novel 440 MHz wireless SAW microsensor integrated with pressure temperature sensors and ID tag

    NASA Astrophysics Data System (ADS)

    Lee, Keekeun; Wang, Wen; Kim, Taehyun; Yang, Sangsik

    2007-03-01

    This paper presents the development of a 440 MHz range surface acoustic wave (SAW)-based microsensor integrated with pressure-temperature sensors and ID tag. Two piezoelectric substrates were bonded, in which a ~150 m air gap was structured by metal poles. The pressure sensor was placed on the top substrate, whereas the ID tag and temperature sensor were located on the bottom substrate. Coupling of modes (COM) modeling was used to find optimal design parameters. Using the extracted optimal design parameters, the SAW device was fabricated. In wireless device testing using a network analyzer, sharp reflection peaks with high S/N ratio, small signal attenuation and small spurious peaks were observed in the time domain. All the reflection peaks were well matched with the predicted values from the simulation. With 10 mW RF power from the network analyzer, a ~1 m readout distance was observed. Depending on applied external pressure, the phase shifts of the reflection peaks were linearly varied. The evaluated sensitivity was about ~2.9 kPa-1. Eight sharp ON reflection peaks were observed for the ID tag. The temperature sensor was characterized from 20 C to 200 C. A large phase shift per unit temperature change was observed.

  5. SoilSaw{trademark} demonstration. Final report, September 1992--January 1995

    SciTech Connect

    Saugier, K.; Isaac, R.E.

    1996-02-01

    The US Department of Energy (DOE) has identified leaking underground storage tanks and buried mixed waste at numerous sites within the DOE complex. Preventing these wastes from entering the environment is a challenging task. One method of preventing waste migration is to isolate the contaminants using subsurface containment barriers. Isolation and containment can be accomplished by both in situ and ex situ methods. This report describes a novel in situ construction method of forming vertical containment barriers (slurry walls) using the SoilSaw{trademark} Barrier System. The SoilSaw{trademark} Barrier System is shown to be a feasible process for constructing subsurface vertical containment barriers to depths of fifty feet. The process is most efficient in sandy soil (including free flowing sand) with barrier construction rates of over 130 square feet per minute. Productivity diminishes to approximately 30 square feet per minute as soils become harder and more cohesive. The present hardware is designed to form a barrier of approximately 12 inch in width. Additional barrier widths can be constructed with this technology by application of wider jet heads. The requirement for a varied arrangement of barrier widths is an increase in hydraulic horse power and additional jet heads.

  6. Design and fabrication of passive wireless sensor array system using composite coding resonant SAW transducer

    NASA Astrophysics Data System (ADS)

    Li, Ping; Wen, Yumei

    2006-02-01

    This paper presents a novel composite SAW (surface acoustic wave) passive wireless sensor system involving a resonator and a delay line. While the interrogational signal is a sinusoidal burst, the response is a delayed and damped oscillation. The frequency and the delay time of response are related to the measurand and the coding of the sensor element, respectively. The composite sensor consists of a SAW resonator and a delay line. It combines the advantages of these two devices and can be used as elements of multiple sensors for longer distance passive wireless measurements. As the wireless sensing response is weak and transient, in order to get the response with the maximum signal-to-noise ratio, the interrogational frequency is designed to be adjustable according to the result of frequency estimation. As a result, an optimal sensing result is achieved. In the transceiver set-up, the software DDS (direct digital synthesis) source with a rather high resolution is implemented to track the passive wireless sensor. An isolated switch is set in transmitter to depress the correlation leakage noise after switching off the wireless RF (radio frequency) interrogation signal. In this paper, the characteristics of the response, the working procedure of the signal processing, sensor temperature test results and the system error analyses are elaborated. A prototype instrument is built. Experimental results show the effectiveness of the instrumentation and the advantages of the composite sensor system.

  7. Buzz-saw noise : propagation of shock waves in aero-engine inlet ducts

    NASA Astrophysics Data System (ADS)

    Fernando, Rasika; Marchiano, Rgis; Coulouvrat, Franois; Druon, Yann

    2008-06-01

    For supersonic flows relative to turbo-engine fan blades, measured acoustic spectra near the inlet present tones at fan blade passing frequency (BPF), engine shaft rotation frequency, or Engine Order (EO), and their respective harmonics. The latter are responsible for the Buzz-saw noise and are thus referred to as "Buzz-saw" or "multiple pure" tones. This work first attempts to reformulate McAlpine and Fisher's frequency domain model (2001) for the propagation of a unidimensional sawtooth waveform spiralling inside a hard-walled cylindrical duct in the presence of a uniform flow. The non-dissipative Burgers equation is solved using a shock fitting method, and modal attenuation and dispersion are added using a split-step computational method. In practice, shocks do not only occur at blade tips but on a significant portion of the blade span. The plane wave hypothesis being no longer valid, a new three dimensional model is required. This model is based on the computation of the axially varying amplitudes of the modal solutions, in order to take into account the nonlinear modal interactions.

  8. Achievable Performance and Effective Interrogator Design for SAW RFID Sensor Tags

    NASA Technical Reports Server (NTRS)

    Barton Richard J.

    2012-01-01

    For many NASA missions, remote sensing is a critical application that supports activities such as environmental monitoring, planetary science, structural shape and health monitoring, non-destructive evaluation, etc. The utility of the remote sensing devices themselves is greatly increased if they are passive V that is, they do not require any on-board power supply such as batteries V and if they can be identified uniquely during the sensor interrogation process. Additional passive sensor characteristics that enable greater utilization in space applications are small size and weight, long read ranges with low interrogator power, ruggedness, and operability in extreme environments (vacuum, extreme high/low temperature, high radiation, etc.) In this paper, we consider one very promising passive sensor technology, called surface acoustic wave (SAW) radio-frequency identification (RFID), that satisfies all of these criteria. In general, RFID is a method of identifying items using radio waves to interrogate tags encoded with a unique identifier that are affixed to the items of interest. In the case of passive tags, only the interrogator, which transmits power to the tags in the form of radio-frequency electromagnetic radiation, requires access to a power supply. Passive RFID technologies are used today in many applications, including asset tracking and management, security and access control, and remote sensing. To date, most of the development and application in RFID technology has focused on either asset/inventory tracking and control or security and access control because these are the largest commercial application areas. Recently however, there has been growing interest in using passive RFID technology for remote sensing applications, and SAW devices are at the forefront of RFID sensing technology development. Although SAW RFID tags have great potential for use in numerous space-based remote sensing applications, the limited collision resolution capability of current generation tags limits the performance in a cluttered sensing environment. That is, as more SAW-based sensors are added to the environment, numerous tag responses are superimposed at the receiver and decoding all or even a subset of the telemetry becomes increasingly difficult. Background clutter generated by reflectors other than the sensors themselves is also a problem, as is multipath interference and signal distortion, but the limiting factor in many remote sensing applications can be expected to be tag mutual interference. This problem may be greatly mitigated by proper design of the SAW tag waveform, but that remains an open research problem, and in the meantime, several other related questions remain to be answered including: (1) What are the fundamental relationships between tag parameters such as bit-rate, time-bandwidth-product, SNR, and achievable collision resolution? (2) What are the differences in optimal or near-optimal interrogator designs between noise-limited environments and interference-limited environments? (3) What are the performance characteristics of different interrogator designs in term of parameters such as transmitter power level, range, and number of interfering tags? In this paper, we will present the results of a research effort aimed at providing at least partial answers to all of these questions.

  9. [The peculiarities of deposition of foreign particles in the skin region experimentally damaged by the electrical saw cutting element].

    PubMed

    Nazarov, Yu V

    2015-01-01

    The objective of the present study was to detect the deposition of foreign particles and other introduced objects in the human skin region damaged by the electrical saw cutting elements and to use the data thus obtained for the estimation of the speed and the type of the instrument, the main characteristics of the cutter covering and/or composition of its surface. The experiments included the sawing of the skin fragments using the small steel saws differing in the type of the surface cover, such as the uncoated (steel), stained, nickel- or chromium-plated, blue-finished saws with the movement speed of the cutting element 500, 1000, 2500, 2,000, and 3,000 revolutions per minute. The study provided information about the peculiarities of deposition of foreign particles and other introduced objects in the damaged regions of the human skin that allow not only to establish the fact of using the electrical saw with a high-speed back-and-forth movements of the cutting element but also the type of the instrument and the main characteristics of its cover and/or the composition of its surface. PMID:26856056

  10. Occupational Injuries in Ohio Wood Product Manufacturing: A Descriptive Analysis With Emphasis on Saw-Related Injuries and Associated Causes

    PubMed Central

    Beery, Lindsay; Harris, James R.; Collins, James W.; Current, Richard S.; Amendola, Alfred A.; Meyers, Alysha R.; Wurzelbacher, Steven J.; Lampl, Mike; Bertke, Stephen J.

    2015-01-01

    Background Stationary sawing machinery is often a basic tool in the wood product manufacturing industry and was the source for over 2,500 injury/illness events that resulted in days away from work in 2010. Methods We examined 9 years of workers compensation claims for the state of Ohio in wood product manufacturing with specific attention to saw-related claims. For the study period, 8,547 claims were evaluated; from this group, 716 saw-related cases were examined. Results The sawmills and wood preservation sub-sector experienced a 71% reduction in average incidence rate and an 87% reduction in average lost-time incidence rate from 2001 to 2009. The top three injury category descriptions for lost-time incidents within saw-related claims were fracture (35.8%), open wounds (29.6%), and amputation (14.8%). Conclusions For saw-related injuries, preventing blade contact remains important but securing the work piece to prevent kickback is also important. PMID:25123487

  11. Efficient light deflection of a narrow guided beam in LiNbO3 using two SAW pulses

    NASA Astrophysics Data System (ADS)

    Yamashita, T.; Matano, M.; Inoue, N.; Katoh, M.

    1985-01-01

    Consideration is given to a new narrow guided beam design with enhanced optical deflection efficiency due to dual surface acoustic wave (SAW) pulses. The main idea behind the design is the use of multiple SAW transducers aligned along the axes of an LiNbO3 waveguide so that: (1) all the excited SAW pulses are deflected simultaneously; and (2) each light beam deflected by a corresponding SAW pulse is not interfered with by an adjacent SAW pulse. The performance characteristics of the device were investigated experimentally using a He-Ne laser and a photomultiplier connected to a pair of wide-channel waveguides and a slab waveguide. Waveforms of the Bragg deflection in the single-transducer and dual-transducer configurations were obtained, and deflection efficiencies were derived as a function of the electrical input power of 350 MHz. It is shown that the deflection efficiency of the waveguide was increased by 20 percent in the dual-transducer configuration. Some applications of acoustooptic narrow guided beams in signal processing devices are discussed.

  12. Comparison of the sensitive property between soman and its simulant DMMP by hydrogen-bond acidic polymer coated SAW sensor

    NASA Astrophysics Data System (ADS)

    Wang, Yang; Du, Xiaosong; Long, Yin; Jiang, Yadong

    2014-08-01

    Hydrogen-bond acidic (HBA) polymers are widely used for the detection of dimethyl methyl phosphonate (DMMP, a simulant of real nerve agents) based on surface acoustic wave (SAW) sensors. This paper presented an HBA polymer PLF, and subsequently the polymer was dissolved into chloroform and spray-coated on a SAW device to fabricate a gas sensor. Then the sensor was equipped into a SAW test platform to investigate its sensitive property to soman vapor and its simulant DMMP at the concentrations below 20 mg/m3. Results revealed that the sensor showed high sensitivity to the analyte vapors, furthermore, the response of the sensor to soman vapor was relatively smaller and slower than that to DMMP. Tests to some common interference vapors were studied at the concentration of 10 mg/m3, and the results indicated that the sensor showed a good selective property.

  13. [Dispersion of the nematodes belonging to the Bursaphelenchus xylophilus species group with saw timber in Russian Federation].

    PubMed

    Akhmatovich, N A; Ryss, A Iu

    2009-01-01

    Four new records of Bursaphelenchus mucronatus in saw-timbers from the Asian part of Russia (Irkutsk Oblast and Krasnoyarsk Krai, larch, pine and spruce wood) intercepted in St. Petersburg, are described, measured and illustrated. The diagnosis of B. mucronatus is amended and its relationships within species group xylophilus, and especially its differences from a quarantine pests B. xylophilus, are given. The record of the B. mucronatus transition from Asiatic into European part of Russia suggests possible transcontinental way of the xylophilus group penetration with saw-timber. Pest risk analysis of B. xylophilus for the European part of Russia is discussed in scope of the global warming. PMID:20198962

  14. Application of Taguchi robust design method to SAW mass sensing device.

    PubMed

    Wu, Der Ho; Chen, Hsin Hua

    2005-12-01

    It is essential that measurement systems provide an accurate and robust performance over a wide range of input conditions. This paper adopts Taguchi's signal-to-noise ratio (SNR) analysis to develop a robust design for the Rayleigh surface acoustic wave (SAW) gas sensing device operated in a conventional delay-line configuration. The goal of the present Taguchi design activity is to increase the sensitivity of this sensor while simultaneously reducing its variability. A time- and cost-efficient finite-element analysis method is used to investigate the effects on the sensor's response output of variations in the carbon dioxide (CO2) gas deposited mass. The simulation results for the resonant frequency and wave mode analysis are all shown to be in good agreement with the values predicted theoretically. PMID:16463507

  15. Trusted Network Selection using SAW and TOPSIS Algorithms for Heterogeneous Wireless Networks

    NASA Astrophysics Data System (ADS)

    Savitha, K.; Chandrasekar, C.

    2011-07-01

    Seamless continuity is the main goal in fourth generation Wireless networks (FGWNs), to achieve this "HANDOVER" technique is used, when a mobile terminal(MT) is in overlapping area for service continuity, Handover mechanism are mainly used. In Heterogeneous wireless networks main challenge is continual connection among the different networks like WiFi, WiMax, WLAN, WPAN etc. In this paper, Vertical handover decision schemes are compared and Multi Attribute Decision Making (MADM) is used to choose the best network from the available Visitor networks (VTs) for the continuous connection by the mobile terminal. In our work we mainly concentrated to the handover decision phase and to reduce the processing delay in the period of handover. MADM algorithms SAW and TOPSIS where compared to reduce the processing delay by using NS2 to evaluate the parameters for processing delay.

  16. Shape-Selectivity with Liquid Crystal and Side-Chain Liquid Crystalline Polymer SAW Sensor Interfaces

    SciTech Connect

    FRYE-MASON,GREGORY CHARLES; OBORNY,MICHAEL C.; PUGH,COLEEN; RICCO,ANTONIO; THOMAS,ROSS C.; ZELLERS,EDWARD T.; ZHANG,GUO-ZHENG

    1999-09-23

    A liquid crystal (LC) and a side-chain liquid crystalline polymer (SCLCP) were tested as surface acoustic wave (SAW) vapor sensor coatings for discriminating between pairs of isomeric organic vapors. Both exhibit room temperature smectic mesophases. Temperature, electric-field, and pretreatment with self-assembled monolayers comprising either a methyl-terminated or carboxylic acid-terminated alkane thiol anchored to a gold layer in the delay path of the sensor were explored as means of affecting the alignment and selectivity of the LC and SCLCP films. Results for the LC were mixed, while those for the SCLCP showed a consistent preference for the more rod-like isomer of each isomer pair examined.

  17. Automatic computer-aided design of SAW filters using slanted finger interdigital transducers.

    PubMed

    Yatsuda, H; Yamanouchi, K

    2000-01-01

    This paper describes a design procedure for surface acoustic wave (SAW) filters using slanted finger interdigital transducers (SFIT) that are suitable for mid-band or wideband applications. The SFITs cannot represent the impulse response directly, in contrast to apodized IDTs. A design method for SFITs based on a building-block approach in the frequency domain is described. An automatic computer-aided design tool for SFIT filters has been achieved. The SFIT filters can be designed using a withdrawal weighting for stop-band responses, an aperture weighting for pass-band amplitude responses, and a distance weighting for pass-band phase responses. In addition, a SFIT pattern for photo mask can be automatically designed using this tool. Using this tool, an SFIT filter with a relative bandwidth of 15% was designed on an x-cut 112y-direction LiTaO(3) substrate. PMID:18238525

  18. SAW RFID-Tags for Mass-Sensitive Detection of Humidity and Vapors.

    PubMed

    Lieberzeit, Peter A; Palfinger, Christian; Dickert, Franz L; Fischerauer, Gerhard

    2009-01-01

    One-port surface acoustic wave (SAW) devices with defined reflector patterns give characteristic signal patterns in the time domain making them identifiable and leading to so-called RFID-Tags. Each sensor responds with a burst of signals, their timed positions giving the identification code, while the amplitudes can be related to the analyte concentration. This paper presents the first combination of such a transducer with chemically sensitive layer materials. These include crosslinked polyvinyl alcohol for determining relative humidity and tert-butylcalix[4]arene for detecting solvent vapors coated on the free space between the reflectors. In going from the time domain to the frequency domain by Fourier transformation, changes in frequency and phase lead to sensor responses. Hence, it is possible to measure the concentration of tetrachloroethene in air down to 50 ppm, as well as 1% changes in relative humidity. PMID:22303149

  19. Los Alamos National Laboratory corregated metal pipe saw facility preliminary safety analysis report. Volume I

    SciTech Connect

    1990-09-19

    This Preliminary Safety Analysis Report addresses site assessment, facility design and construction, and design operation of the processing systems in the Corrugated Metal Pipe Saw Facility with respect to normal and abnormal conditions. Potential hazards are identified, credible accidents relative to the operation of the facility and the process systems are analyzed, and the consequences of postulated accidents are presented. The risk associated with normal operations, abnormal operations, and natural phenomena are analyzed. The accident analysis presented shows that the impact of the facility will be acceptable for all foreseeable normal and abnormal conditions of operation. Specifically, under normal conditions the facility will have impacts within the limits posted by applicable DOE guidelines, and in accident conditions the facility will similarly meet or exceed the requirements of all applicable standards. 16 figs., 6 tabs.

  20. Economics of ingot slicing with an internal diameter saw for low-cost solar cells

    NASA Technical Reports Server (NTRS)

    Daud, T.; Liu, J. K.; Fiegl, G.

    1981-01-01

    Slicing of silicon ingots using diamond impregnated internal diameter blade saws has been a standard technology of the semiconductor industry. This paper describes work on improvements to this technology for 10 cm diameter ingot slicing. Ingot rotation, dynamic blade edge control with feedback, mechanized blade dressing and development of thinner blades are the approaches tried. A comparison of the results for wafering with and without ingot rotation is also made. A sensitivity analysis of the major cost elements in wafering is performed for 10 cm diameter ingot and extended to the 15 cm diameter ingot case. Various parameter values such as machine cost, feed rate and consumable materials cost are identified both for single and multiple ingot slicing.

  1. Ultra low-power hybrid spintronics-straintronics clocked with Surface Acoustic Waves (SAW)

    NASA Astrophysics Data System (ADS)

    Salehi Fashami, Mohammad; Bandyopadhyay, Supriyo; Atulasimha, Jayasimha

    2014-03-01

    The study of magnetization dynamics in magnetostrictive materials triggered with surface acoustic waves (SAWs) is of great interest not only from a fundamental point of view, but also for potential applications in energy efficient nanomagnetic computing. In this presentation, we model magnetization dynamics in dipole coupled arrays of nanomagnets clocked by acoustic waves. Specifically, this theoretical work demonstrates the feasibility of sequential logic devices such as flip-flops by showing that NAND gates and information propagation with cross-over of nanomagnet ``wires'' can be implemented and synchronously clocked with surface acoustic waves. We acknowledge support of the National Science Foundation (NSF) under NSF CAREER grant CCF-1253370, the NEB2020 Grant ECCS-1124714 and SHF grant CCF-1216614 as well as the Semiconductor Research Company (SRC) under NRI task 2203.001.

  2. Evaluation of Residual Stresses Using Laser-Generated SAWs on Surface of Laser-Welding Plates

    NASA Astrophysics Data System (ADS)

    Dong, Li-ming; Li, Jia; Ni, Chen-yin; Shen, Zhong-hua; Ni, Xiao-wu

    2013-06-01

    In this paper, residual stresses in laser-welding plates are studied by both numerical simulation and experiment based on laser ultrasonics. First, a three-dimensional finite-element model is developed to predict temperature distributions and thermo-structure response during the laser-welding process of an aluminum alloy plate, and the residual stresses around the joint are described from structure analysis. After that, experiments based on surface acoustic waves generated by a pulsed laser are carried out to determine the velocity distribution of SAWs around the joint, from which the distribution of main residual stresses are calculated according to acoustoelastic theory. By comparing the thermal-structure model results with the measurements, it is found that the numerical simulation results are in good agreement with the experimental data.

  3. Transverse waveguide mode suppression for Pt-electrode SAW resonators on quartz and LGS.

    PubMed

    Meulendyk, Bennett J; Pereira da Cunha, Mauricio

    2011-12-01

    SAW resonators on ST-X quartz and langasite (LGS) [0, 144, 24] are currently being used for hydrogen fluoride (HF) vapor sensing and high-temperature sensing, respectively. For these applications, the use of Pt-based electrodes allows the resonators to withstand the targeted harsh environments. This work reveals that for Pt-electrode resonators with conventional short-circuit gratings on the aforementioned quartz and LGS orientations, acoustic energy leaks from the grating region to the bus bars, thus degrading the resonator response. To resolve this problem, this paper proposes and implements open-circuit gratings for resonators fabricated with these substrate/metal combinations. The open-circuit gratings guide the acoustic energy within the grating region, resulting in greater quality factors and reduced losses in the resonator response. In addition, scalar potential theory is utilized in this work to identify transverse waveguide modes in the responses of open-circuit grating resonators on quartz and LGS. A transverse waveguide mode dispersion relation was derived to extend the scalar potential theory to account for asymmetry in the slowness curve around the propagation direction. This is the case for several commonly used LGS orientations, in particular LGS [0, 144, 24]. Finally, this work addresses spurious transverse mode mitigation by scaling both the transducer's grating aperture and electrode overlap width. Open circuit grating resonators with appropriately scaled transducer designs were fabricated and tested, resulting in a 71% increase in quality factor and a spurious mode rejection of over 26 dBc for Pt-electrode devices on ST-X quartz. This progress directly translates into better frequency resolution and increased dynamic range for HF vapor sensors and high-temperature SAW devices. PMID:23443708

  4. Distraction osteogenesis for complex foot deformities: Gigli saw midfoot osteotomy with external fixation.

    PubMed

    Lamm, Bradley M; Gourdine-Shaw, Monique C; Thabet, Ahmed M; Jindal, Gaurav; Herzenberg, John E; Burghardt, Rolf D

    2014-01-01

    Open midfoot wedge osteotomy correction can cause neurovascular compromise, requires extensive exposure, sacrifices normal joints, and shortens the foot. We used a minimally invasive technique to treat complex foot deformities by combining percutaneous Gigli saw midfoot osteotomy, circular external fixation, and acute, gradual, or gradual with acute manipulation correction. The medical records of 23 patients (26 feet) with complex foot deformities (congenital, 18 feet; neuromuscular, 4 feet; post-traumatic, 3 feet; malunion, 1 foot) who had undergone treatment within an 18-year period (1990 through 2007) were retrospectively reviewed. We also performed the procedure on 10 cadaveric limbs to determine whether anatomic structures were at risk. Correction was achieved in all feet. The mean duration of external fixation treatment was 4.2 (range 3 to 7) months. The mean follow-up duration was 4.7 (range 2 to 18) years. A significant difference was observed in the pre- and postoperative, lateral view, talar-first metatarsal angle (p = .001). Minor complications (4 feet) consisted of bony exostoses. Major complications included recurrent deformity in 3 feet and sural nerve entrapment in 1 foot. Two patients had mild and one moderate foot pain. Three patients had impaired gait function; the remaining patients had functional gait. The mean interval until wearing regular shoes after external fixation removal was 2.3 (range 1 to 4) months. All but 1 of the patients were satisfied with the final results. We observed no cadaveric neurovascular injury. Our results have shown that percutaneous Gigli saw midfoot osteotomy can be performed without neurovascular injury and is capable of successfully correcting complex foot deformities. PMID:24891089

  5. Combination of a SAW-biosensor with MALDI mass spectrometric analysis.

    PubMed

    Treitz, G; Gronewold, T M A; Quandt, E; Zabe-Khn, M

    2008-05-15

    A S-sens K5 surface acoustic wave biosensor was coupled with mass spectrometry (SAW-MS) for the analysis of a protein complex consisting of human blood clotting cascade factor alpha-thrombin and human antithrombin III, a specific blood plasma inhibitor of thrombin. Specific binding of antithrombin III to thrombin was recorded as a function of time with a S-sens K5 biosensor. Two out of five elements of the sensor chip were used as references. To the remaining three elements coated with RNA anti-thrombin aptamers, thrombin and antithrombin III were bound consecutively. The biosensor measures mass changes on the chip surface showing that 20% of about 400fmol/cm2 thrombin formed a complex with the 1.7-times larger antithrombin III. Mass spectrometry (MS) was applied to identify the bound proteins. Sensor chips with aptamer-captured (1) thrombin and (2) thrombin-antithrombin III complex (TAT-complex) were digested with proteases on the sensor element and subsequently identified by peptide mass fingerprint (PMF) with matrix assisted laser desorption/ionization time-of-flight (MALDI-ToF) mass spectrometry. A significant identification of thrombin was achieved by measuring the entire digest with MALDI-ToF MS directly from the sensor chip surface. For the significant identification of both proteins in the TAT-complex, the proteolytic peptides had to be separated by nano-capillary-HPLC prior to MALDI-ToF MS. SAW-MS is applicable to protein interaction analysis as in functional proteomics and to miniaturized diagnostics. PMID:18316185

  6. New Mass Properties Engineers Aerospace Ballasting Challenge Facilitated by the SAWE Community

    NASA Technical Reports Server (NTRS)

    Cutright, Amanda; Shaughnessy, Brendan

    2010-01-01

    The discipline of Mass Properties Engineering tends to find the engineers; not typically vice versa. In this case, two engineers quickly found their new responsibilities deep in many aspects of mass properties engineering and required to meet technical challenges in a fast paced environment. As part of NASA's Constellation Program, a series of flight tests will be conducted to evaluate components of the new spacecraft launch vehicles. One of these tests is the Pad Abort 1 (PA-1) flight test which will test the Launch Abort System (LAS), a system designed to provide escape for astronauts in the event of an emergency. The Flight Test Articles (FTA) used in this flight test are required to match mass properties corresponding to the operational vehicle, which has a continually evolving design. Additionally, since the structure and subsystems for the Orion Crew Module (CM) FTA are simplified versions of the final product, thousands of pounds of ballast are necessary to achieve the desired mass properties. These new mass properties engineers are responsible for many mass properties aspects in support of the flight test, including meeting the ballasting challenge for the CM Boilerplate FTA. SAWE expert and experienced mass properties engineers, both those that are directly on the team and many that supported via a variety of Society venues, significantly contributed to facilitating the success of addressing this particular mass properties ballasting challenge, in addition to many other challenges along the way. This paper discusses the details regarding the technical aspects of this particular mass properties challenge, as well as identifies recommendations for new mass properties engineers that were learned from the SAWE community along the way.

  7. AlN films deposited by dc magnetron sputtering and high power impulse magnetron sputtering for SAW applications

    NASA Astrophysics Data System (ADS)

    Ait Aissa, K.; Achour, A.; Elmazria, O.; Simon, Q.; Elhosni, M.; Boulet, P.; Robert, S.; Djouadi, M. A.

    2015-04-01

    In this work, aluminium nitride (AlN) films were deposited on silicon substrates buffered by an epitaxial AlN thin film for surface acoustic wave (SAW) applications. The films were deposited by dc magnetron sputtering (dcMS) and high power impulse magnetron sputtering (HiPIMS) deposition techniques. The structural properties of AlN films were investigated using x-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy and atomic force microscopy. In both cases of films deposited by dcMS and HiPIMS, the XRD results showed that the obtained films are oriented, with full width at half maximum rocking curves of around 1°. Raman spectroscopy revealed higher residual stress relaxation in the AlN epilayers grown by HiPIMS compared to AlN grown by dcMS, highlighted by a blue shift in the E2(high) Raman mode. The SAW measurements indicated an insertion loss of AlN-SAW devices of about 53 and 35 dB for the AlN films deposited by dcMS and HiPIMS respectively. The relation between the structural properties of AlN and the characteristics of AlN-SAW devices were correlated and discussed.

  8. On the Old Saw That Dialogue Is a Socratic but Not an Aristotelian Method of Moral Education

    ERIC Educational Resources Information Center

    Kristjnsson, Kristjn

    2014-01-01

    Kristjn Kristjnsson's aim in this article is to bury the old saw that dialogue is exclusively a Socratic but not an Aristotelian method of education for moral character. Although the truncated discussion in Aristotle's "Nicomachean Ethics" of the character development of the young may indicate that it is merely the result of

  9. On the Old Saw That Dialogue Is a Socratic but Not an Aristotelian Method of Moral Education

    ERIC Educational Resources Information Center

    Kristjánsson, Kristján

    2014-01-01

    Kristján Kristjánsson's aim in this article is to bury the old saw that dialogue is exclusively a Socratic but not an Aristotelian method of education for moral character. Although the truncated discussion in Aristotle's "Nicomachean Ethics" of the character development of the young may indicate that it is merely the result of…

  10. 76 FR 62678 - Table Saw Blade Contact Injuries; Advance Notice of Proposed Rulemaking; Request for Comments and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-11

    ... accidental contact with the blade. In the Federal Register of July 9, 2003 (68 FR 40912) and September 5, 2003 (68 FR 52753), we invited comments on the issues raised by the petition (Petition No. CP03-2). We... COMMISSION 16 CFR Chapter II Table Saw Blade Contact Injuries; Advance Notice of Proposed Rulemaking;...

  11. DNA immobilization and SAW response in ZnO nanotips grown on LiNbO3 substrates.

    PubMed

    Zhang, Zheng; Emanetoglu, Nuri William; Saraf, Gaurav; Chen, Yimin; Wu, Pan; Zhong, Jian; Lu, Yicheng; Chen, Jingqiu; Mirochnitchenko, Oleg; Inouye, Masayori

    2006-04-01

    DNA immobilization enhancement is demonstrated in a structure consisting of ZnO nanotips on 128 degrees Y-cut LiNbO3. The ZnO nanotips are grown by metalorganic chemical vapor deposition (MOCVD) on the top of a SiO2 layer that is deposited and patterned on the LiNbO3 SAW delay path. The effects of ZnO nanotips on the SAW response are investigated. X-ray diffraction and scanning electron microscopy are used to analyze the ZnO nanotips, which are of single crystalline quality, and they are uniformly aligned with their c-axis perpendicular to the substrate surface. The photoluminescence (PL) spectrum of the ZnO nanotips shows strong near bandedge transition with insignificant deep level emission, confirming their good optical property. DNA immobilization enhancement is experimentally validated by radioactive labeling tests and SAW response changes. The ZnO nanotips enhance the DNA immobilization by a factor of 200 compared to ZnO film with flat surface. DNA hybridization with complementary and noncomplementary second strand DNA oligonucleotides is used to study the selective binding of the structure. This device structure possesses the advantages of both traditional SAW sensors and ZnO nanostructures. PMID:16615583

  12. Surface Acoustic Waves (SAW)-Based Biosensing for Quantification of Cell Growth in 2D and 3D Cultures

    PubMed Central

    Wang, Tao; Green, Ryan; Nair, Rajesh Ramakrishnan; Howell, Mark; Mohapatra, Subhra; Guldiken, Rasim; Mohapatra, Shyam Sundar

    2015-01-01

    Detection and quantification of cell viability and growth in two-dimensional (2D) and three-dimensional (3D) cell cultures commonly involve harvesting of cells and therefore requires a parallel set-up of several replicates for time-lapse or dose–response studies. Thus, developing a non-invasive and touch-free detection of cell growth in longitudinal studies of 3D tumor spheroid cultures or of stem cell regeneration remains a major unmet need. Since surface acoustic waves (SAWs) permit mass loading-based biosensing and have been touted due to their many advantages including low cost, small size and ease of assembly, we examined the potential of SAW-biosensing to detect and quantify cell growth. Herein, we demonstrate that a shear horizontal-surface acoustic waves (SH-SAW) device comprising two pairs of resonators consisting of interdigital transducers and reflecting fingers can be used to quantify mass loading by the cells in suspension as well as within a 3D cell culture platform. A 3D COMSOL model was built to simulate the mass loading response of increasing concentrations of cells in suspension in the polydimethylsiloxane (PDMS) well in order to predict the characteristics and optimize the design of the SH-SAW biosensor. The simulated relative frequency shift from the two oscillatory circuit systems (one of which functions as control) were found to be concordant to experimental data generated with RAW264.7 macrophage and A549 cancer cells. In addition, results showed that SAW measurements per se did not affect viability of cells. Further, SH-SAW biosensing was applied to A549 cells cultured on a 3D electrospun nanofiber scaffold that generate tumor spheroids (tumoroids) and the results showed the device's ability to detect changes in tumor spheroid growth over the course of eight days. Taken together, these results demonstrate the use of SH-SAW device for detection and quantification of cell growth changes over time in 2D suspension cultures and in 3D cell culture models, which may have potential applications in both longitudinal 3D cell cultures in cancer biology and in regenerative medicine. PMID:26703604

  13. Surface Acoustic Waves (SAW)-Based Biosensing for Quantification of Cell Growth in 2D and 3D Cultures.

    PubMed

    Wang, Tao; Green, Ryan; Nair, Rajesh Ramakrishnan; Howell, Mark; Mohapatra, Subhra; Guldiken, Rasim; Mohapatra, Shyam Sundar

    2015-01-01

    Detection and quantification of cell viability and growth in two-dimensional (2D) and three-dimensional (3D) cell cultures commonly involve harvesting of cells and therefore requires a parallel set-up of several replicates for time-lapse or dose-response studies. Thus, developing a non-invasive and touch-free detection of cell growth in longitudinal studies of 3D tumor spheroid cultures or of stem cell regeneration remains a major unmet need. Since surface acoustic waves (SAWs) permit mass loading-based biosensing and have been touted due to their many advantages including low cost, small size and ease of assembly, we examined the potential of SAW-biosensing to detect and quantify cell growth. Herein, we demonstrate that a shear horizontal-surface acoustic waves (SH-SAW) device comprising two pairs of resonators consisting of interdigital transducers and reflecting fingers can be used to quantify mass loading by the cells in suspension as well as within a 3D cell culture platform. A 3D COMSOL model was built to simulate the mass loading response of increasing concentrations of cells in suspension in the polydimethylsiloxane (PDMS) well in order to predict the characteristics and optimize the design of the SH-SAW biosensor. The simulated relative frequency shift from the two oscillatory circuit systems (one of which functions as control) were found to be concordant to experimental data generated with RAW264.7 macrophage and A549 cancer cells. In addition, results showed that SAW measurements per se did not affect viability of cells. Further, SH-SAW biosensing was applied to A549 cells cultured on a 3D electrospun nanofiber scaffold that generate tumor spheroids (tumoroids) and the results showed the device's ability to detect changes in tumor spheroid growth over the course of eight days. Taken together, these results demonstrate the use of SH-SAW device for detection and quantification of cell growth changes over time in 2D suspension cultures and in 3D cell culture models, which may have potential applications in both longitudinal 3D cell cultures in cancer biology and in regenerative medicine. PMID:26703604

  14. A phytochemical comparison of saw palmetto products using gas chromatography and 1H nuclear magnetic resonance spectroscopy metabolomic profiling

    PubMed Central

    Booker, Anthony; Suter, Andy; Krnjic, Ana; Strassel, Brigitte; Zloh, Mire; Said, Mazlina; Heinrich, Michael

    2014-01-01

    Objectives Preparations containing saw palmetto berries are used in the treatment of benign prostatic hyperplasia (BPH). There are many products on the market, and relatively little is known about their chemical variability and specifically the composition and quality of different saw palmetto products notwithstanding that in 2000, an international consultation paper from the major urological associations from the five continents on treatments for BPH demanded further research on this topic. Here, we compare two analytical approaches and characterise 57 different saw palmetto products. Methods An established method gas chromatography was used for the quantification of nine fatty acids, while a novel approach of metabolomic profiling using 1H nuclear magnetic resonance (NMR) spectroscopy was used as a fingerprinting tool to assess the overall composition of the extracts. Key findings The phytochemical analysis determining the fatty acids showed a high level of heterogeneity of the different products in the total amount and of nine single fatty acids. A robust and reproducible 1H NMR spectroscopy method was established, and the results showed that it was possible to statistically differentiate between saw palmetto products that had been extracted under different conditions but not between products that used a similar extraction method. Principal component analysis was able to determine those products that had significantly different metabolites. Conclusions The metabolomic approach developed offers novel opportunities for quality control along the value chain of saw palmetto and needs to be followed further, as with this method, the complexity of a herbal extract can be better assessed than with the analysis of a single group of constituents. PMID:24417505

  15. Predicting the Relationship Between System Vibration with Rock Brittleness Indexes in Rock Sawing Process

    NASA Astrophysics Data System (ADS)

    Mikaeil, Reza; Ataei, Mohammad; Ghadernejad, Saleh; Sadegheslam, Golsa

    2014-03-01

    The system vibration is a very significant measure of the sawing performance, because it indicates the amount of energy required to saw the rock. The maintenance cost of system is also dependant on system vibration. A few increases in system vibration cause a huge increase in the maintenance cost of the system. In this paper, the vibration of system in terms of RMSa was investigated and models for estimation of vibration by means of rock brittleness indexes and operational specifications were designed via statistical models and multiple curvilinear regression analysis. In this study, the relationships between rock brittleness indexes and operational specifications were investigated by regression analysis in statistical package for social science (SPSS) and the results of determination coefficients have been presented. In the second part, the diagrams show that a point lying on the line indicates an exact estimation. In the plot for model, the points are scattered uniformly about the diagonal line, suggesting that the models are good. It is very useful to evaluate the vibration of system and select the suitable operational characteristics by only some mechanical properties of rock. Drgania uk?adu uwa?ane s? za miernik wydajno?ci procesu urabiania, poniewa? pokazuj? ilo?? energii niezb?dnej do urabiania ska?y. Od poziomu drga? zale?? tak?e koszty eksploatacji systemu. Nieznaczny nawet wzrost poziomu drga? prowadzi do znacznego zwi?kszenia kosztw eksploatacyjnych urz?dzenia. W pracy tej przeprowadzono analiz? drga? (ich warto?ci skutecznych) i opracowano model estymacji poziomu drga? w oparciu o wsp?czynnik krucho?ci ska? i parametry eksploatacyjne urz?dzenia. W pracy wykorzystano modele statystyczne i wielokrotn? analiz? metod? regresji krzywoliniowej. W pracy obecnej zwi?zek pomi?dzy wsp?czynnikiem krucho?ci ska? a parametrami eksploatacyjnymi urz?dzenia badano z wykorzystaniem analizy metod? regresji dost?pnej w statystycznym pakiecie oprogramowania dla nauk spo?ecznych (SPSS) a wyniki podano w postaci wyznaczonych wsp?czynnikw. W drugiej cz??ci pracy przedstawiono wykres pokazuj?cy, ze punkt le??cy na linii oznacza dok?adne oszacowanie. W wykresie wykonanym dla modelu punkty rozrzucone s? rwnomiernie wok? linii przek?tnej, co sugeruje ?e modele s? w?a?ciwe. Okre?lenie poziomu drga? urz?dzenia jest niezwykle korzystnym zabiegiem pozwalaj?cym na dobr parametrw pracy urz?dzenia jedynie w oparciu o mechaniczne w?a?ciwo?ci ska?.

  16. Characterizing components of the Saw Palmetto Berry Extract (SPBE) on prostate cancer cell growth and traction.

    PubMed

    Scholtysek, Carina; Krukiewicz, Aleksandra A; Alonso, José-Luis; Sharma, Karan P; Sharma, Pal C; Goldmann, Wolfgang H

    2009-02-13

    Saw Palmetto Berry Extract (SPBE) is applied for prostate health and treatment of urinary tract infections, nonbacterial prostitis and Benign Prostatic Hyperplasia (BPH) in man. An assumption is that SPBE affects tumor cell progression and migration in breast and prostate tissue. In this work, DU-145 cells were used to demonstrate that SPBE and its sterol components, beta-sitosterol and stigmasterol, inhibit prostate cancer growth by increasing p53 protein expression and also inhibit carcinoma development by decreasing p21 and p27 protein expression. In the presence of cholesterol, these features are not only reversed but increased significantly. The results show for the first time the potential of SPBE, beta-sitosterol and stigmasterol as potential anti-tumor agents. Since the protein p53 is also regarded as nuclear matrix protein facilitating actin cytoskeletal binding, 2D tractions were measured. The cell adhesion strength in the presence of SPBE, beta-sitosterol and cholesterol and the observation was that the increase in p53 expression triggered an increase in the intracellular force generation. The results suggest a dual function of p53 in cells. PMID:19059205

  17. Hierarchical nanostructures of diblock copolymer thin films directed by a saw-toothed substrate.

    PubMed

    Peng, Mengjie; Ma, Shiying; Hu, Jinglei; Wang, Rong

    2015-09-01

    An extensive and systematic calculation was performed to explore hierarchical cylindrical structures and the order-to-order transitions of AB diblock copolymers (f(A) = 0.3) on a saw-toothed substrate using self-consistent mean-field theory. We obtained fifteen relatively simple morphologies, including the existing morphologies observed experimentally and from simulations, and five more complicated structures, by varying the lateral periodicity of the substrate, the film thickness of diblock copolymers, the interaction between the A-block and the substrate and the tilt angles (or the shape) of the substrate. These structures show that the orientation and number of layers of cylinders can be tailored. Even lamellae and spherical microdomains were observed. Most interestingly, hierarchical structures are also observed, such as the morphology of C(ab)(//) within the upper cylinder perpendicular to the bottom cylinder, SC(b)(//) morphology that the upper is a cylinder but the bottom is a sphere. In addition, we discussed these complex hierarchical structures in detail and have analyzed the order-to-order transitions between the cylindrical morphologies with distinct orientations and layers. PMID:26212500

  18. [Effect of adding amendments on preserving nitrogen during chicken manure and saw composting].

    PubMed

    Huang, Yimei; Qu, Dong; Li, Guoxue

    2003-03-01

    In the automatic aerobic compost device, experiments were carried out to investigate the effect of four amendments on inhibition of nitrogen losses during the chicken manure and saw composting. The changes of chemical parameters, temperature, pH, water soluble ammonium and organic nitrogen, total nitrogen and organic carbon with time during the aerobic composting process were investigated. The results suggested that adding four amendments have certain effect on preserve nitrogen and chemical parameters. Treatments added different amendments all decreased the nitrogen losses and increased the decomposition of organic carbon for 40 days-composting. The effect extent of four amendments was adding peat and superphosphate together > adding peat > adding superphosphate > adding zeolite. Especially adding peat and superphosphate together prolonged the high temperature stage 5 days, decreased the pH 0.89 pH unit in the initial stage and 0.44 pH unit in the high temperature stage during composting, and it decreased the nitrogen losses about 65.1% during the composting. PMID:12800680

  19. Flux composition, microstructure and mechanical properties of HY-100 SAW weldments

    SciTech Connect

    Brothers, D.G.; Kettell, K.W.; Fox, A.G.

    1994-12-31

    The mechanical properties of submerged arc welds (SAW) on high strength steels are sensitive to weld-metal chemistry and thus the chemical composition of the welding consumables. Consumable chemistry determines the size, distribution, and composition of the nonmetallic inclusions present in the weld metal which together with cooling rate determines weld-metal microstructure and thus mechanical properties. Multirun submerged arc welds were made on HY-100 steel and all-weld variables were kept constant except the flux composition for which five different commercial fluxes were investigated. The basicity of each flux was calculated and correlated with weld-metal chemistry and it was found that lower basicity fluxes appeared to generate a higher oxygen activity in the weld-metal leading to more pronounced oxidation of carbon, manganese, and silicon and thus loss of weld-metal yield strength. Inclusion analyses showed the inclusion in the weld-metals to contain MnO, Al{sub 2}O{sub 3}, SiO{sub 2}, and TiO{sub 2}. These results suggest that the optimum flux for welding high-strength steels should have a high enough basicity and MnO content to avoid the loss of alloying elements from the weld metal due to high oxygen activity and to generate sufficient numbers of non-metallic inclusions to keep the DBTT low by forming significant amounts of acicular ferrite.

  20. Characterizing components of the Saw Palmetto Berry Extract (SPBE) on prostate cancer cell growth and traction

    SciTech Connect

    Scholtysek, Carina; Krukiewicz, Aleksandra A.; Alonso, Jose-Luis; Goldmann, Wolfgang H.

    2009-02-13

    Saw Palmetto Berry Extract (SPBE) is applied for prostate health and treatment of urinary tract infections, nonbacterial prostitis and Benign Prostatic Hyperplasia (BPH) in man. An assumption is that SPBE affects tumor cell progression and migration in breast and prostate tissue. In this work, DU-145 cells were used to demonstrate that SPBE and its sterol components, {beta}-sitosterol and stigmasterol, inhibit prostate cancer growth by increasing p53 protein expression and also inhibit carcinoma development by decreasing p21 and p27 protein expression. In the presence of cholesterol, these features are not only reversed but increased significantly. The results show for the first time the potential of SPBE, {beta}-sitosterol and stigmasterol as potential anti-tumor agents. Since the protein p53 is also regarded as nuclear matrix protein facilitating actin cytoskeletal binding, 2D tractions were measured. The cell adhesion strength in the presence of SPBE, {beta}-sitosterol and cholesterol and the observation was that the increase in p53 expression triggered an increase in the intracellular force generation. The results suggest a dual function of p53 in cells.

  1. Chemical quality of the Saw Mill River, Westchester County, New York, 1981-83

    USGS Publications Warehouse

    Rogers, R.J.

    1984-01-01

    Surface waters, bottom sediments and coatings formed on artificial substrates (ceramic tiles) were analyzed to evaluate the chemical quality of the Saw Mill River, New York. Heavy metals, nutrients, and organic contaminants were studied. Dissolved orthophosphate concentrations were highest in the lower third of the river. Dissolved manganese was the only metal to exceed U.S. Environmental Protection Agency water-quality criteria. Arsenic, cadmium, copper, lead, and zinc concentrations were highest in waters from the lowest 4 river miles. Concentrations of copper, lead, and zinc in bottom sediments from the lowest 3 river miles were greater than in upstream sediments. Concentrations of nine heavy metals were higher on tiles emplaced below river mile 3 than on tiles upstream. Few organic compounds were detected in the water column; none persisted at all sites. Chlordane, DDD, DDE, DDT, dieldrin, and polychlorinated biphenyls (PCB's) were found in bottom sediments throughout the basin. PCB concentrations were highest in the lowest 6 river miles; the other organic compounds exhibited no spatial patterns. Polynuclear aromatic hydrocarbons were most abundant in bottom sediments from the lowest 2 river miles. Collectively the distribution of contaminants indicates that river quality deteriorates in the lower, more heavily urbanized reach. (USGS)

  2. Application of convolve-multiply-convolve SAW processor for satellite communications

    NASA Technical Reports Server (NTRS)

    Lie, Y. S.; Ching, M.

    1991-01-01

    There is a need for a satellite communications receiver than can perform simultaneous multi-channel processing of single channel per carrier (SCPC) signals originating from various small (mobile or fixed) earth stations. The number of ground users can be as many as 1000. Conventional techniques of simultaneously processing these signals is by employing as many RF-bandpass filters as the number of channels. Consequently, such an approach would result in a bulky receiver, which becomes impractical for satellite applications. A unique approach utilizing a realtime surface acoustic wave (SAW) chirp transform processor is presented. The application of a Convolve-Multiply-Convolve (CMC) chirp transform processor is described. The CMC processor transforms each input channel into a unique timeslot, while preserving its modulation content (in this case QPSK). Subsequently, each channel is individually demodulated without the need of input channel filters. Circuit complexity is significantly reduced, because the output frequency of the CMC processor is common for all input channel frequencies. The results of theoretical analysis and experimental results are in good agreement.

  3. Saw-tooth refractive lens for high energy x-ray focusing

    NASA Astrophysics Data System (ADS)

    Antimonov, Mikhail A.; Khounsary, Ali M.

    2014-09-01

    Saw-tooth refractive lens (SRL) provides a comparatively attractive option for X-ray focusing. An SRL assembly consists of two parts, each with an array of triangular structures (prisms), set tilted symmetrically with respect to the incoming beam. Its main advantage is a simple, continuous tunability in energy and focal length. SRLs can be used for both long and short focal length focusing. Long focal distance focusing of an SRL can accurately be predicted using simple analytical relations. However, the focus size at short focal distances focusing may deviate appreciably from the expected demagnified source size when: (1) the length of the SRL is comparable with the focusing distance, (2) the incident beam is not monochromatic, and (3) and the distance between adjacent prism tips, the tip step, is large . The first factor was considered in a previous work while the other two are addressed is this paper. This preliminary work is aimed at a better understanding of the SRL lenses for focusing an undulator beamline at the Advanced Photon Source (APS).

  4. Continuous in vivo blood pressure measurements using a fully implantable wireless SAW sensor.

    PubMed

    Murphy, Olive H; Bahmanyar, Mohammad Reza; Borghi, Alessandro; McLeod, Christopher N; Navaratnarajah, Manoraj; Yacoub, Magdi H; Toumazou, Christofer

    2013-10-01

    In this paper, the development of a fully implantable wireless sensor able to provide continuous real-time accurate pressure measurements is presented. Surface Acoustic Wave (SAW) technology was used to deposit resonators on crystalline quartz wafers; the wafers were then assembled to produce a pressure sensitive device. Excitation and reading via a miniature antenna attached to the pressure sensor enables continuous external interrogation. The main advantages of such a configuration are the long term stability of quartz and the low power necessary for the interrogation, which allows 24/7 interrogation by means of a hand-held, battery powered device. Such data are of vital importance to clinicians monitoring and treating the effects of hypertension and heart failure. A prototype was designed and tested using both a bio-phantom test rig and an animal model. The pressure traces for both compare very well with a commercially available catheter tip pressure transducer. The work presented in this paper is the first known wireless pressure data from the left ventricle of the heart of a living swine. PMID:23559403

  5. Design of SAW filters in SS-FDMA routers for mobile satellite systems

    NASA Astrophysics Data System (ADS)

    Ananasso, Fulvio; Deacon, John M.

    1989-11-01

    The present paper reports the design of a SAW filter bank consisting of 26 linear phase filters with bandwidths ranging from 60 to 2180 kHz, 0.5/40 dB transition width narrower than 30 kHz, and stopband rejection as high as possible. Passbank amplitude and phase ripple limits are 1 dB and 4 deg peak-to-peak respectively. Three candidate filters of bandwidth 60 kHz, 400 kHz and 2.180 MHz were selected for detailed design, taking into account spurious effects such as acoustic regeneration and diffraction as well as technology limits. The electrical specifications are met by all but the 2180 kHz filter, whose shape factor, for a 30 kHz transition band, would be 1.027 : 1, beyond the state of the art. The filter bank has about 27 dB insertion loss per filter, plus roughly 14 dB (1 : 26) power split loss.

  6. Pharmacological effects of saw palmetto extract in the lower urinary tract

    PubMed Central

    Suzuki, Mayumi; Ito, Yoshihiko; Fujino, Tomomi; Abe, Masayuki; Umegaki, Keizo; Onoue, Satomi; Noguchi, Hiroshi; Yamada, Shizuo

    2009-01-01

    Saw palmetto extract (SPE), an extract from the ripe berries of the American dwarf palm, has been widely used as a therapeutic remedy for urinary dysfunction due to benign prostatic hyperplasia (BPH) in Europe. Numerous mechanisms of action have been proposed for SPE, including the inhibition of 5α-reductase. Today, α1-adrenoceptor antagonists and muscarinic cholinoceptor antagonists are commonly used in the treatment of men with voiding symptoms secondary to BPH. The improvement of voiding symptoms in patients taking SPE may arise from its binding to pharmacologically relevant receptors in the lower urinary tract, such as α1-adrenoceptors, muscarinic cholinoceptors, 1,4-dihyropyridine receptors and vanilloid receptors. Furthermore, oral administration of SPE has been shown to attenuate the up-regulation of α1-adrenoceptors in the rat prostate induced by testosterone. Thus, SPE at clinically relevant doses may exert a direct effect on the pharmacological receptors in the lower urinary tract, thereby improving urinary dysfunction in patients with BPH and an overactive bladder. SPE does not have interactions with co-administered drugs or serious adverse events in blood biochemical parameters, suggestive of its relative safety, even with long-term intake. Clinical trials (placebo-controlled and active-controlled trials) of SPE conducted in men with BPH were also reviewed. This review should contribute to the understanding of the pharmacological effects of SPE in the treatment of patients with BPH and associated lower urinary tract symptoms (LUTS). PMID:19262550

  7. INTERNATIONAL UNION OF OPERATING ENGINEERS NATIONAL HAZMAT PROGRAM - PORTER-CABLE CIRCULAR SAW OENHP: 2001-04, VERSION A

    SciTech Connect

    Unknown

    2002-01-15

    Florida International University's (FIU) Hemispheric Center for Environmental Technology (HCET) evaluated five saws for their effectiveness in cutting specially prepared fiberglass-reinforced plywood crates. These crates were built as surrogates for crates that presently hold radioactively contaminated glove boxes at the Department of Energy's (DOE) Los Alamos facility. The Porter-Cable circular saw was assessed on August 15-16, 2001 (Porter-Cable No.1 and Porter-Cable No.2, respectively). During the FIU test of efficacy, a team from the Operating Engineers National Hazmat Program (OENHP) evaluated the occupational safety and health issues associated with this technology. The Porter-Cable saw is a straightforward machine for cutting wood of varying thickness. The blade is fully guarded with a fixed upper and a lower retractable guard. The lower guard retracts as the blade engages the work piece. The unit is operated with an on/off guarded trigger switch and is supported with a handgrip mounted near the front of the saw. The saw is equipped with a directional nozzle, which aims sawdust away from the operator and the line of cut. An optional vacuum system, attached to the directional nozzle, is used to remove and collect dust. During the demonstration of Porter-Cable No.1, personal noise sampling indicated that one worker was under and one was at the Occupational Safety and Health Administration's (OSHA) Action Level of 85 decibels (dBA) with time-weighted averages (TWA's) of 82.7 and 84.6 dBA, respectively. During the demonstration of Porter-Cable No.2, however, both workers did exceed the Action Level with TWA's of 89.7 and 90.0 dBA. These data are not entirely representative as they were gathered during a simulation and not at the actual worksite. Additional sampling should be conducted on-site, but the workers should wear hearing protection until it is determined that it is no longer necessary. The total nuisance dust sample for Porter-Cable No.1 was 3.53 milligrams per cubic meter (mg/m{sup 3}), which is lower than the OSHA Permissible Exposure Limit (PEL) of 15 mg/m{sup 3} and the American Conference of Governmental Industrial Hygienists' (ACGIH) Threshold Limit Value (TLV) of 10 mg/m{sup 3}. Porter-Cable No.2's nuisance dust results yielded a value of 22.05 mg/m{sup 3}, which is over the PEL and TLV. The fiber analysis for the first demonstration yielded 12.9 fibers per cubic centimeter (f/cc), which is much higher than the PEL of 1 f/cc. Galson Laboratories considered the fiber analysis for the second demonstration void due to the overloading of dust on the filter. Kickback, the sudden reaction to a pinched blade, is possible with this saw and could cause the saw to lift up and out of the work piece and toward the operator. Proper work position and firm control of the saw minimizes the potential for a sprain or strain. Care needs to be exercised to support the work piece properly and to not force the tool.

  8. INTERNATIONAL UNION OF OPERATING ENGINEERS NATIONAL HAZMAT PROGRAM - EVOLUTION 180 CIRCULAR SAW OENHP: 2001-03, VERSION A

    SciTech Connect

    Unknown

    2002-01-25

    Florida International University's (FIU) Hemispheric Center for Environmental Technology (HCET) evaluated five saws for their effectiveness in cutting specially prepared fiberglass-reinforced plywood crates. These crates were built as surrogates for crates that presently hold radioactively contaminated gloveboxes at the Department of Energy's (DOE) Los Alamos facility. The Evolution 180 circular saw was assessed on August 14, 2001. During the FIU test of efficacy, a team from the Operating Engineers National Hazmat Program (OENHP) evaluated the occupational safety and health issues associated with this technology. The Evolution 180 is a portable, metal cutting circular saw with a 7-inch diameter blade. The blade is contained within the main housing and has a retractable lower blade guard to prevent operator access to the blade during operation and shutdown. The saw is equipped with a chip collector. The maximum cutting thickness for metal is one-quarter inch and can cut steel tubing and pipe 2 inches in diameter. The unit is operated with an on/off guarded trigger switch and is supported with the hand guide mounted to the side of the saw. An adjustable lever sets the depth of the cut. The machine's circuitry will automatically shut the saw motor off if excessive overload is detected during operation. The one-half hour demonstration involved vertical and horizontal cuts and blade changes. During this process, operators experienced binding of the saw. This caused the blade to become hot, causing the sawdust collected in the chip collector to smoke. Care should be exercised to use the appropriate blade for the application, operator training, and personal protective equipment (PPE). Personal noise sampling indicated that neither worker was over the Occupational Safety and Health Administration's (OSHA) Action Level of 85 decibels (dBA) with time-weighted averages (TWA's) of 69.1 and 68.8 dBA. The personal noise sample taken during the special demonstration with the stainless steel plate had a TWA of 69.8 dBA. These data are not entirely representative as they were gathered during a simulation and not at the actual worksite. Additional sampling should be conducted on-site, but the workers should wear hearing protection until it is determined that it is no longer necessary. The total nuisance dust sample for the Evolution 180 circular saw was 3.5 milligrams per cubic meter (mg/m{sup 3}), which is lower than the OSHA Permissible Exposure Limit (PEL) of 15 mg/m{sup 3} and the American Conference of Governmental Industrial Hygienists' (ACGIH) Threshold Limit Value (TLV) of 10 mg/m{sup 3}. The fiber analysis yielded 1.74 fibers per cubic centimeter (f/cc), which is above the PEL of 1 f/cc. Although the nuisance dust levels were low, fiberglass dust levels were higher than the PEL. Since fiberglass dust is known to be a strong skin irritant and a possible human carcinogen, the workers should continue to wear appropriate suits and gloves, as well as a full-face air-purifying respirator. The respirator should be equipped with a combination organic vapor and acid gas cartridge in combination with a High Particulate Air (HEPA) filter, since particulate filter, since during the demonstration, the workers complained of an odd smell, which may have been from the breakdown of the fiberglass.

  9. A forest without trees: Development of high-surface-area materials for enhanced-sensitivity SAW arrays

    SciTech Connect

    Yelton, W.G.; Ricco, A.J.; Staton, A.W.

    1998-08-01

    Chemical sensor arrays are an alternative to the tedious development of highly specific single-analyte detectors. Recent efforts have focused on the chemical and physical diversity of interface materials for SAW sensor arrays. However, the issues of wide dynamic range and high sensitivity must also be addressed for sensor arrays to compete in applications requiring low detection limits. Because SAW devices respond in proportion to change in mass per nominal unit area of the device surface, sensitivity is enhanced by surface modification with high-area, thin-film coating materials: a greater mass of analyte is adsorbed at a given ambient concentration. The authors are exploring several classes of electrochemically prepared high-area films, materials whose formulations and processing are well documented for applications other than chemical sensors. They present results from films formed by anodization, chemical conversion, and electroplating, yielding surface area enhancements as high as 170x.

  10. The 2.2 GHz Surface Acoustic Wave (SAW) oscillator development Ku-band frequency source development

    NASA Technical Reports Server (NTRS)

    1979-01-01

    Two 2.2 GHz SAW oscillators using aluminum nitride on sapphire (AlN/Al2O3) delay lines were fabricated. The oscillators were electronically temperature compensated and characterized. One of the oscillators was used as the frequency reference for the Ku band source; the second oscillator is available for continued evaluation. A 15 GHz frequency source was designed and fabricated. The 15 GHz source consists of a Ku band FET oscillator which is phase locked to the frequency multiplied (X7) output of the 2.2 GHz SAW reference source. The Ku band source was built using microstrip circuit designs, which are hybrid compatible. Two wafer runs of 2.2 GHz TED devices were fabricated and evaluated. The devices were mounted on microstrip test substrates and evaluated as 15 GHz divide by 7 circuits. The device evaluation indicated that in their present form the TED is not a practical circuit element.

  11. Control of surface mobility for conformal deposition of Mo-Si multilayers on saw-tooth substrates

    NASA Astrophysics Data System (ADS)

    Voronov, D. L.; Anderson, E. H.; Gullikson, E. M.; Salmassi, F.; Warwick, T.; Yashchuk, V. V.; Padmore, H. A.

    2013-11-01

    Multilayer-coated blazed gratings (MBG) are the most promising solution for ultra-high resolution soft X-ray spectroscopy, since they can have very high groove density and provide high-order operation and very high diffraction efficiency. The performance of MBGs however depends critically on the conformal deposition of the multilayer (ML) stack on a saw-tooth substrate and the minimization of roughness. We present an analysis of the roughening and smoothing processes during growth of Mo/Si multilayers deposited over a range of pressures of Ar sputtering gas on flat and saw-tooth substrates. A Linear Continuum Model (LCM) of the film growth was used to understand the interplay between smoothing and roughening of the ML films and to predict the optimum conditions for deposition. The MBG coated under the optimal deposition conditions demonstrated high diffraction efficiency in the EUV and soft X-ray wavelength ranges

  12. Detection of coffee flavour ageing by solid-phase microextraction/surface acoustic wave sensor array technique (SPME/SAW).

    PubMed

    Bari, Nicole; Bcking, Mark; Stahl, Ullrich; Rapp, Michael

    2015-06-01

    The use of polymer coated surface acoustic wave (SAW) sensor arrays is a very promising technique for highly sensitive and selective detection of volatile organic compounds (VOCs). We present new developments to achieve a low cost sensor setup with a sampling method enabling the highly reproducible detection of volatiles even in the ppb range. Since the VOCs of coffee are well known by gas chromatography (GC) research studies, the new sensor array was tested for an easy assessable objective: coffee ageing during storage. As reference method these changes were traced with a standard GC/FID set-up, accompanied by sensory panellists. The evaluation of GC data showed a non-linear characteristic for single compound concentrations as well as for total peak area values, disabling prediction of the coffee age. In contrast, the new SAW sensor array demonstrates a linear dependency, i.e. being capable to show a dependency between volatile concentration and storage time. PMID:25624226

  13. Hierarchical saw-like ZnO nanobelt/ZnS nanowire heterostructures induced by polar surfaces.

    PubMed

    Shen, Guozhen; Chen, Di; Lee, Cheol Jin

    2006-08-17

    Saw-like nanostructures composed of single-crystalline ZnO nanobelts and single-crystalline ZnS nanowires have been successfully synthesized by a vapor-solid process. Several techniques, including scanning electron microscope, transmission electron microscopy, and photoluminescence spectroscopy, were used to investigate the structures, morphology, and photoluminescence properties of the products. Due to the similar crystal habits of wurtzite ZnO and ZnS with chemically active Zn-terminated (0001) and chemically inactive O-terminated (or S-terminated) (000) polar surfaces, hierarchical saw-like nanostructures were considered to be formed by the initiation of a chemically active Zn-terminated ZnO (0001) polar surface. Photoluminescence properties of the heterostructures, different from pure ZnO nanobelts or ZnS nanowires, were also studied at room temperature. PMID:16898712

  14. Survey of blood parasites in two forest owls, Northern Saw-whet Owls and Flammulated Owls, of western North America.

    PubMed

    Leppert, Lynda L; Dufty, Alfred M; Stock, Sarah; Oleyar, M David; Kaltenecker, Greg S

    2008-04-01

    Except for a few studies in the eastern United States, little has been published on hemoparasites in owls. We surveyed the blood parasites of 108 Northern Saw-whet Owls (Aegolius acadicus) and 24 Flammulated Owls (Otus flammeolus) in Idaho during autumn migration in 1999 and 2000. We also surveyed 15 Flammulated Owls (FLOW) during breeding season in Utah from 2000. Leucocytozoon ziemanni, Haemoproteus syrnii, Haemoproteus noctuae, and Trypanosoma avium were identified. The overall prevalence of infection was 53% (78/147) and for the combined species, prevalences of Haemoproteus, Leucocytozoon, and Trypanosoma species were 20%, 39%, and 4%, respectively. Northern Saw-whet Owls (NSWO) had an overall prevalence of 51% (55/108), with prevalences of 6%, 47%, and 4% by hemoparasite genus, respectively. Flammulated Owls had an overall prevalence of 59% (23/39), with prevalences of 56%, 18%, and 5% by genus, respectively. This study provides baseline hematozoa information for two boreal owl species. PMID:18436683

  15. Achieving optimal flatness and surface roughness properties for novel x-ray optic structures formed by dicing saws

    NASA Astrophysics Data System (ADS)

    Wieczorek, Michael; Khachatryan, Ruben; Shvyd'ko, Yuri; Smith, Robert H.; Iwasaki, Kenichi; Miller, Suzanne; Qian, Jun; Huang, Xianrong; Assoufid, Lahsen

    2012-10-01

    Crystal-based x-ray optics are widely used in the synchrotron radiation field. Such optics include monochromators, channel-cut crystals, spectral analyzers, and phase plates that are generally made with standard fabrication tools such as grinders, ultrasonic mills, blade saws, and wire saws. However, modern synchrotron radiation instruments require more complicated and high-precision crystal structures that cannot be fabricated by these conventional tools. Examples include narrow channels and crystal cavities that require smooth and strain-free sidewalls or inner surfaces. Since it is extremely difficult to polish such surfaces by conventional means, specialized cutting tools are required to make the as-cut surfaces as smooth as possible. A possible way to obtain such smooth surfaces is to use a dicing saw as a fabrication tool - a tool typically used in the microelectronics industry to cut or dice semiconductor and other materials. Here we present our studies on the use of dicing saws for cutting innovative, monolithic, x-ray optic devices comprised of tall, narrow-standing, thin crystal-plate arrays. We report cutting parameters that include the rotational speed of the cutting blade (a.k.a. spindle speed), cutting speed (a.k.a. feed rate), number of passes for each cut depth (if required), and diamond grit size for producing the flattest and most smooth side walls. Blade type and construction (sintered, Ni, and resin) also play critical roles in achieving optimum results. The best experimental data obtained produced an average surface roughness of 49 nm and a peak-to-valley flatness of 3625 nm. By achieving these results, we have been able to assist experimenters in the synchrotron radiation field in their efforts to create functional and novel optical devices.

  16. Effects of pumpkin seed oil and saw palmetto oil in Korean men with symptomatic benign prostatic hyperplasia

    PubMed Central

    Hong, Heeok; Kim, Chun-Soo

    2009-01-01

    This study was to investigate the role of complementary and alternative medicine in the prevention and treatment of benign prostatic hyperplasia. For this purpose, a randomized, double-blind, placebo-controlled trial was performed over 12 months on 47 benign prostatic hyperplasia patients with average age of 53.3 years and international prostate symptom score over 8. Subjects received either sweet potato starch (group A, placebo, 320 mg/day), pumpkin seed oil (group B, 320 mg/day), saw palmetto oil (group C, 320 mg/day) or pumpkin seed oil plus saw palmetto oil (group D, each 320 mg/day). International prostate symptom score, quality of life, serum prostate specific antigen, prostate volume and maximal urinary flow rate were measured. In groups B, C and D, the international prostate symptom score were reduced by 3 months. Quality of life score was improved after 6 months in group D, while those of groups B and C were improved after 3 months, compared to the baseline value. Serum prostate specific antigen was reduced only in group D after 3 months, but no difference was observed in prostate volume in all treatment groups. Maximal urinary flow rate were gradually improved in groups B and C, with statistical significance after 6 months in group B and after 12 months in group C. None of the parameters were significantly improved by combined treatment with pumpkin seed oil and saw palmetto oil. From these results, it is suggested that administrations of pumpkin seed oil and saw palmetto oil are clinically safe and may be effective as complementary and alternative medicine treatments for benign prostatic hyperplasia. PMID:20098586

  17. Quasi-static field analysis of SAW devices with arbitrary geometries of electrodes and of metallic enclosures.

    PubMed

    Reichinger, H; Baghai-Wadji, A R

    1994-01-01

    An easy-to-implement, accurate, and fast method to calculate 2-D quasi-static capacitance and inductance of electrodes in SAW devices is presented. The method is outlined by considering electrodes with any cross-section geometries in dielectric environment, consisting of two anisotropic materials with a plane interface. The analysis allows the inclusion of arbitrarily shaped metallic packages. A significant shift of charges on enclosures, due to the substrate anisotropy, is observed. PMID:18263267

  18. A New Hyphenated ? TrapGCSurface Acoustic Wave (SAW) Based Electronic Nose For Monitoring Of Coffee Quality

    NASA Astrophysics Data System (ADS)

    Carvalho, Mauro; Voigt, Achim; Rapp, Michael

    2009-05-01

    An easy-to-use and versatile analytical method for complex matrix analisis like coffee was developed. The system consists of a microtrap sample preparation, a home made simplified gaschomatographic separation unit and an 8-fold surface acoustic wave based sensors (SAW) array detector. For the coffee quality analysis a successful discrimination of three coffee samples could be achieved. The system would be further developed into a fully automated, low cost version that can be broadly used by the coffee producers.

  19. Material property evaluations of bimetallic welds, stainless steel saw fusion lines, and materials affected by dynamic strain aging

    SciTech Connect

    Rudland, D.; Scott, P.; Marschall, C.; Wilkowski, G.

    1997-04-01

    Pipe fracture analyses can often reasonably predict the behavior of flawed piping. However, there are material applications with uncertainties in fracture behavior. This paper summarizes work on three such cases. First, the fracture behavior of bimetallic welds are discussed. The purpose of the study was to determine if current fracture analyses can predict the response of pipe with flaws in bimetallic welds. The weld joined sections of A516 Grade 70 carbon steel to F316 stainless steel. The crack was along the carbon steel base metal to Inconel 182 weld metal fusion line. Material properties from tensile and C(T) specimens were used to predict large pipe response. The major conclusion from the work is that fracture behavior of the weld could be evaluated with reasonable accuracy using properties of the carbon steel pipe and conventional J-estimation analyses. However, results may not be generally true for all bimetallic welds. Second, the toughness of austenitic steel submerged-arc weld (SAW) fusion lines is discussed. During large-scale pipe tests with flaws in the center of the SAW, the crack tended to grow into the fusion line. The fracture toughness of the base metal, the SAW, and the fusion line were determined and compared. The major conclusion reached is that although the fusion line had a higher initiation toughness than the weld metal, the fusion-line J-R curve reached a steady-state value while the SAW J-R curve increased. Last, carbon steel fracture experiments containing circumferential flaws with periods of unstable crack jumps during steady ductile tearing are discussed. These instabilities are believed to be due to dynamic strain aging (DSA). The paper discusses DSA, a screening criteria developed to predict DSA, and the ability of the current J-based methodologies to assess the effect of these crack instabilities. The effect of loading rate on the strength and toughness of several different carbon steel pipes at LWR temperatures is also discussed.

  20. Combined FEM and Green's function analysis of periodic SAW structure, application to the calculation of reflection and scattering parameters.

    PubMed

    Ventura, P; Hod, J M; Desbois, J; Solal, M

    2001-09-01

    Because of more and more stringent requirements on SAW filter performances, it is important to compute, with very good accuracy, the SAW propagation characteristics, which include the calculation of reflection and scattering parameters. For that reason, the analysis of periodic structures on a semi-infinite piezoelectric substrate is one of the most important problems being investigated by SAW researchers. For infinite periodic grating modeling, we developed numerical mixed FEM/BEM (finite element method-boundary element method) models using an efficient interpolation basis function that takes into account the singularity at both edges of each electrode. In this paper, a review of the numerical program that has been developed during the past few years will be presented. For an infinite periodic grating, it is convenient to solve the propagation problem in the Fourier domain (wave number space and harmonic excitation), and important efforts have been spent to properly integrate the so-called periodic harmonic Green function. Using this numerical model together with the general P- matrix formalism, it is possible to compute all of the basic parameters with a very good accuracy. These consist of the single strip reflectivity, acoustic wave-phase velocity, and position offset between reflection and transduction centers. Simulations and comparisons with experiments are shown for each model. PMID:11570750

  1. Safe fronto-orbito-zygomatic osteotomy using a diamond-coated threadwire saw in orbito-zygomatic craniotomy

    PubMed Central

    Wada, Kojiro; Mori, Kentaro; Toyooka, Terushige; Otani, Naoki; Fujii, Kazuya; Ueno, Hideaki; Tomura, Satoshi; Tomiyama, Arata

    2015-01-01

    Orbito-zygomatic craniotomy is a widely accepted skull-based technique, but osteotomy at the malar eminence (ME) is complicated. We have developed a safe fronto-orbito-zygomatic (FOZ) osteotomy by creating small guide burr holes in the superior and lateral parts of the orbital wall and cutting the bone using a diamond-coated threadwire saw. This method involves standard two-piece osteotomy by creating small superior and lateral guide orbital burr holes instead of sectioning into the superior and inferior orbital fissures. The guide burr holes are connected using a diamond-coated threadwire saw to create the FOZ bar. This method was applied to the treatment of four patients with skull-based tumors or internal carotid and basilar artery aneurysms. Postoperative three-dimensional bone density computed tomography showed minimum bone gap in the ME. No craniotomy-related complication has occurred. FOZ osteotomy by creating guide burr holes in the orbital wall and cutting the bone using a diamond-coated threadwire saw is safe and results in minimum bone gap in the ME. PMID:26396621

  2. A comparison of protocols for the optimisation of detection of bacteria using a surface acoustic wave (SAW) biosensor.

    PubMed

    Howe, E; Harding, G

    2000-01-01

    A dual channel surface acoustic wave (SAW) device has been used as a biosensor to detect two different microorganisms, Legionella and Escherichia coli, simultaneously. A series of experiments was conducted to optimise the use of the SAW for bacterial detection using a novel protocol of coating bacteria on the sensor surface prior to addition of the antibody. Results were compared with an experiment in which a conventional protocol was utilised, where antibody was coated on the sensor surface prior to exposure to bacteria. The concentration of bacteria that attached to the surface of the SAW device was related to the antibody that specifically bound to it and therefore to frequency in a dose dependent fashion. Unlike conventional microbiological techniques quantitative results can be obtained for Legionella and E. coli down to 10(6) cells per ml within 3 h. In addition E. coli was detected down to 10(5) cells per ml in a modified protocol using sheep IgG as a blocking agent. PMID:11213225

  3. Modelling based on Spatial Impulse Response Model for Optimization of Inter Digital Transducers (SAW Sensors) for Non Destructive Testing

    NASA Astrophysics Data System (ADS)

    Fall, D.; Duquennoy, M.; Ouaftouh, M.; Piwakowski, B.; Jenot, F.

    This study deals with modelling SAW-IDT transducers for their optimization. These sensors are specifically developed to characterize properties of thin layers, coatings and functional surfaces. Among the methods of characterization, the ultrasonic methods using Rayleigh surface waves are particularly interesting because the propagation of these waves is close to the surface of material and the energy is concentrated within a layer under the surface of about one wavelength thick. In order to characterize these coatings and structures, it is necessary to work in high frequencies, this is why in this study, SAW-IDT sensors are realized for surface acoustic wave generation. For optimization of these SAW-IDT sensors, particularly their band-width, it is necessary to study various IDT configurations by varying the number of electrodes, dimensions of the electrodes, their shapes and spacings. Thus it is necessary to implement effective and rapid technique for modelling. The originality of this study is to develop simulation tools based on Spatial Impulse Response model. Therefore it will be possible to reduce considerably computing time and results are obtained in a few seconds, instead of several hours (or days) by using finite element method. In order to validate this method, theoretical and experimental results are compared with finite element method and Interferometric measurements. The results obtained show a good overall concordance and confirm effectiveness of suggested method.

  4. Detection, Identification, Location, and Remote Sensing using SAW RFID Sensor Tags

    NASA Technical Reports Server (NTRS)

    Barton, Richard J.

    2009-01-01

    In this presentation, we will consider the problem of simultaneous detection, identification, location estimation, and remote sensing for multiple objects. In particular, we will describe the design and testing of a wireless system capable of simultaneously detecting the presence of multiple objects, identifying each object, and acquiring both a low-resolution estimate of location and a high-resolution estimate of temperature for each object based on wireless interrogation of passive surface acoustic wave (SAW) radiofrequency identification (RFID) sensor tags affixed to each object. The system is being studied for application on the lunar surface as well as for terrestrial remote sensing applications such as pre-launch monitoring and testing of spacecraft on the launch pad and monitoring of test facilities. The system utilizes a digitally beam-formed planar receiving antenna array to extend range and provide direction-of-arrival information coupled with an approximate maximum-likelihood signal processing algorithm to provide near-optimal estimation of both range and temperature. The system is capable of forming a large number of beams within the field of view and resolving the information from several tags within each beam. The combination of both spatial and waveform discrimination provides the capability to track and monitor telemetry from a large number of objects appearing simultaneously within the field of view of the receiving array. In the presentation, we will summarize the system design and illustrate several aspects of the operational characteristics and signal structure. We will examine the theoretical performance characteristics of the system and compare the theoretical results with results obtained from experiments in both controlled laboratory environments and in the field.

  5. Mechanical comparison of fixation techniques for the offset V osteotomy: a saw bone study.

    PubMed

    Jacobson, Keith; Gough, Adam; Mendicino, Samuel S; Rockett, Matthew S

    2003-01-01

    Four different techniques for the fixation of an offset V bunionectomy were tested on solid-foam saw-bone models for the purpose of determining the strongest form of fixation for the osteotomy. Twenty identical models were placed into 4 different groups. Groups varied as to the placement and caliber of fixation. Models were loaded with a servo-hydraulic testing machine until failure of fixation occurred. Video analysis was used to record the pattern of failure of the fixation. Failure occurred either distal to the first screw, through the first screw hole, between the 2 screws, through the second screw hole, or proximal to the second screw. The mean force to failure of the groups was group 1, 58.1 N; group 2, 59.3 N; group 3, 64.0 N; and group 4, 105.66 N. There was a statistical significant difference between group 4 and the other 3 groups (F(1) = 55.45, P < 0.05). There was no statistical difference between groups 1 to 3. In groups 1 to 3, 87% of the failures were through the distal screw hole, whereas the remaining 13% were through the proximal screw hole. In group 4, 60% of the failures were through the proximal screw hole and 40% were through the distal screw hole. It was concluded that, in this model, the strongest form of fixation for an offset V osteotomy was the 2.7-mm cortical screw placed distally with the proximal point of fixation being a threaded 0.062-inch Kirschner wire. PMID:14688775

  6. See-saw rocking: an in vitro model for mechanotransduction research

    PubMed Central

    Tucker, R. P.; Henningsson, P.; Franklin, S. L.; Chen, D.; Ventikos, Y.; Bomphrey, R. J.; Thompson, M. S.

    2014-01-01

    In vitro mechanotransduction studies, uncovering the basic science of the response of cells to mechanical forces, are essential for progress in tissue engineering and its clinical application. Many varying investigations have described a multitude of cell responses; however, as the precise nature and magnitude of the stresses applied are infrequently reported and rarely validated, the experiments are often not comparable, limiting research progress. This paper provides physical and biological validation of a widely available fluid stimulation device, a see-saw rocker, as an in vitro model for cyclic fluid shear stress mechanotransduction. This allows linkage between precisely characterized stimuli and cell monolayer response in a convenient six-well plate format. Models of one well were discretized and analysed extensively using computational fluid dynamics to generate convergent, stable and consistent predictions of the cyclic fluid velocity vectors at a rocking frequency of 0.5 Hz, accounting for the free surface. Validation was provided by comparison with flow velocities measured experimentally using particle image velocimetry. Qualitative flow behaviour was matched and quantitative analysis showed agreement at representative locations and time points. Maximum shear stress of 0.22 Pa was estimated near the well edge, and time-average shear stress ranged between 0.029 and 0.068 Pa. Human tenocytes stimulated using the system showed significant increases in collagen and GAG secretion at 2 and 7 day time points. This in vitro model for mechanotransduction provides a versatile, flexible and inexpensive method for the fluid shear stress impact on biological cells to be studied. PMID:24898022

  7. Structural Loading on the QCM/SAW Instrument Aboard the ER-2 Used for Atmospheric Testing

    NASA Technical Reports Server (NTRS)

    Bainum, Peter M.; Jones, Phyllis D.; Irish, Sandra M.; Xing, Guang-Qian

    1998-01-01

    Several experiments have been proposed to capture and evaluate samples of the atmosphere where SST's travel. One means to achieve this is to utilize the quartz crystal microbalance (QCM) / surface acoustical wave (SAW) instrument installed aboard the ER-2, formerly the U-2 reconnaissance aircraft. The QCM is a cascade impactor designed to perform in-situ, real-time measurements of aerosols and chemical vapors at an altitude of 60,000-70,000 feet. The primary use of the ER-2 is by NASA for Earth resources to test new sensor systems before being placed aboard satellites. One of the main reasons the ER-2 is used for this flight experiment is its capability to fly approximately twelve miles above the sea level (can reach an altitude of 78,000 feet). Because the ER-2 operates at such a high altitude, it is of special interest to scientists interested in space exploration or supersonic aircraft. The purpose of some of the experiments is to extinct data from the atmosphere around the ER-2. For the current CSTEA flight experiment, the housing of the QCM is in a frame that connects to an outer pod that attaches to the fuselage of the ER-2. Due to the location of the QCM within the housing frame and the location of the pod on the ER-2, the pod and its contents are subject to structural loads. In addition to structural loads, structural vibrations are also of importance because the QCM output data is based on the determination of beat frequencies between a pair of oscillators (one coated, the second uncoated, according to the chemical reaction being monitored). A structural analysis of this system can indicate whether potential resonances may exist between the (higher) structural modal frequencies and the beat frequencies. In addition undesirable deformations may result due to maximum expected static or dynamic loads during typical flight conditions. If the deformations are excessive they may adversely affect the accuracy the instrumentation output.

  8. INTERNATIONAL UNION OF OPERATING ENGINEERS NATIONAL HAZMAT PROGRAM - DEWALT RECIPROCATING SAW OENHP{number_sign}: 2001-01, VERSION A

    SciTech Connect

    Unknown

    2002-01-31

    Florida International University's (FIU) Hemispheric Center for Environmental Technology (HCET) evaluated five saws for their effectiveness in cutting specially prepared fiberglass-reinforced plywood crates. These crates were built as surrogates for crates that presently hold radioactively contaminated glove boxes at the Department of Energy's (DOE) Los Alamos facility. The DeWalt reciprocating saw was assessed on August 13, 2001. During the FIU test of efficacy, a team from the Operating Engineers National Hazmat Program (OENHP) evaluated the occupational safety and health issues associated with this technology. The DeWalt reciprocating saw is a hand-held industrial tool used for cutting numerous materials, including wood and various types of metals depending upon the chosen blade. Its design allows for cutting close to floors, corners, and other difficult areas. An adjustable shoe sets the cut at three separate depths. During the demonstration for the dismantling of the fiberglass-reinforced plywood crate, the saw was used for extended continuous cutting, over a period of approximately two hours. The dismantling operation involved vertical and horizontal cuts, saw blade changes, and material handling. During this process, operators experienced vibration to the hand and arm in addition to a temperature rise on the handgrip. The blade of the saw is partially exposed during handling and fully exposed during blade changes. Administrative controls, such as duty time of the operators and the machine, operator training, and personal protective equipment (PPE), such as gloves, should be considered when using the saw in this application. Personal noise sampling indicated that both workers were exposed to noise levels exceeding the Occupational Safety and Health Administration's (OSHA) Action Level of 85 decibels (dBA) with time-weighted averages (TWA's) of 88.3 and 90.6 dBA. Normally, a worker would be placed in a hearing conservation program if his TWA was greater than the Action Level. In this case, however, monitoring was conducted during a simulation, not during the actual work conducted at the worksite. Additional sampling should be conducted at the worksite to determine the actual noise levels for the workers. Until it is determined that the actual TWA's are less than the Action Level, the workers should use PPE. A training program on the proper use and wearing of the selected PPE should be provided to each worker. Nuisance dust monitoring yielded a concentration of 10.69 milligrams per cubic meter (mg/m{sup 3}). Although this is less than the OSHA Permissible Exposure Limit (PEL) of 15 mg/m{sup 3}, it is above the American Conference of Governmental Industrial Hygienists' (ACGIH) Threshold Limit Value (TLV) of 10 mg/m{sup 3}. Fiberglass dust monitoring yielded a fiber count of 1.7 fibers per cubic centimeter (f/cc). This is above the PEL and the TLV of 1.0 f/cc. Therefore, controls should be implemented (engineering or PPE) to reduce the workers' exposure to the dust. Respirators should be used if engineering controls do not sufficiently control the dust or fiberglass generated. Respirators should be equipped with an organic vapor and acid gas cartridge with a High Efficiency Particulate Air (HEPA) filter, since during the demonstration, the workers complained of an odd smell, which may have been from the breakdown of the fiberglass.

  9. [The establishment of the fact of the application of an electric circular saw with the high-speed reciprocating motion of the blade].

    PubMed

    Nazarov, Iu V; Tolmachev, I A; Bozhchenko, A P

    2014-01-01

    This paper reports a case of forensic medical expertise of an unintentional (accidental) injury inflicted by an electric circular saw with the high-speed reciprocating motion of the blade (jigsaw) under conditions of human operational activities. PMID:25764881

  10. A SAW-Based Chemical Sensor for Detecting Sulfur-Containing Organophosphorus Compounds Using a Two-Step Self-Assembly and Molecular Imprinting Technology

    PubMed Central

    Pan, Yong; Yang, Liu; Mu, Ning; Shao, Shengyu; Wang, Wen; Xie, Xiao; He, Shitang

    2014-01-01

    This paper presents a new effective approach for the sensitive film deposition of surface acoustic wave (SAW) chemical sensors for detecting organophosphorus compounds such as O-ethyl-S-2-diisopropylaminoethyl methylphosphonothiolate (VX) containing sulfur at extremely low concentrations. To improve the adsorptive efficiency, a two-step technology is proposed for the sensitive film preparation on the SAW delay line utilizing gold electrodes. First, mono[6-deoxy-6-[(mercaptodecamethylene)thio

  11. A SAW-based chemical sensor for detecting sulfur-containing organophosphorus compounds using a two-step self-assembly and molecular imprinting technology.

    PubMed

    Pan, Yong; Yang, Liu; Mu, Ning; Shao, Shengyu; Wang, Wen; Xie, Xiao; He, Shitang

    2014-01-01

    This paper presents a new effective approach for the sensitive film deposition of surface acoustic wave (SAW) chemical sensors for detecting organophosphorus compounds such as O-ethyl-S-2-diisopropylaminoethyl methylphosphonothiolate (VX) containing sulfur at extremely low concentrations. To improve the adsorptive efficiency, a two-step technology is proposed for the sensitive film preparation on the SAW delay line utilizing gold electrodes. First, mono[6-deoxy-6-[(mercaptodecamethylene)thio

  12. Deep Sub-micro mol{\\cdot }mol^{-1} Water-Vapor Measurement by Dual-Ball SAW Sensors for Temperature Compensation

    NASA Astrophysics Data System (ADS)

    Takeda, N.; Oizumi, T.; Tsuji, T.; Akao, S.; Takayanagi, K.; Nakaso, N.; Yamanaka, K.

    2015-12-01

    A collimated surface acoustic wave (SAW) circles around the equator of a sphere hundreds of times. Because of the long distance travel of the collimated SAW, a small change in the SAW propagation caused by the environment of the sphere can be accumulated as a measurable range in amplitude and/or in delay time. So, a spherical SAW device enables highly sensitive water-vapor measurements. In this paper, deep sub \\upmu mol{\\cdot }mol^{-1} water-vapor detection by 1 mm diameter quartz crystal ball SAW sensors is described. To measure such a low water-vapor concentration in real time, it is necessary to compensate the temperature dependence of the ball SAW sensor, which is about 20 ppm{\\cdot }°C^{-1} in delay time change. A dual-frequency burst analog detector was developed for the temperature compensation in real time. By using a harmonic SAW sensor, which was excited by 80 MHz and 240 MHz at the same time, it was confirmed that the delay time drift for a temperature range of 21.0°C ± 1.0°C became less than 0.05 ppm in delay time change. By using dual-ball SAW sensors (which included a 150 MHz sensor with a water-vapor sensitive layer and a 240 MHz sensor as a reference), water-vapor concentrations from 0.1 \\upmu mol{\\cdot }mol^{-1} to 5 \\upmu mol{\\cdot }mol^{-1} were successfully measured. It appears that the delay time change is proportional to the square root of the water-vapor concentration. The detection limit determined by the electrical noise of the system was estimated at 0.01 \\upmu mol{\\cdot }mol^{-1}.

  13. Local heat transfer distribution in a square channel with 90 continuous, 90 saw tooth profiled and 60 broken ribs

    SciTech Connect

    Gupta, Abhishek; SriHarsha, V.; Prabhu, S.V.; Vedula, R.P.

    2008-02-15

    Internal channel cooling is employed in advanced gas turbines blade to allow high inlet temperatures so as to achieve high thrust/weight ratios and low specific fuel consumption. The objective of the present study is to measure the local heat transfer distributions in a double wall ribbed square channel with 90 continuous, 90 saw tooth profiled and 60 V-broken ribs. Comparison is made between the 90 continuous ribs (P/e = 7 and 10 for a e/D = 0.15) and 90 saw tooth profiled rib configurations (P/e = 7 for an e/D = 0.15) for the same rib height to the hydraulic diameter ratio (e/D). The effect of pitch to rib height ratio (P/e = 7.5,10 and 12) of 60 V-broken ribbed channel with a constant rib height to hydraulic diameter ratio (e/D) of 0.0625 on the local heat transfer distribution is studied. The Reynolds number based on duct hydraulic diameter is ranging from 10,000 to 30,000. A thin stainless steel foil of 0.05 mm thickness is used as heater and infrared thermography technique is used to obtain the local temperature distribution on the surface. The images are captured in the periodically fully developed region of the channel. It is observed that the heat transfer augmentations in the channel with 90 saw tooth profiled ribs are comparable with those of 90 continuous ribs. The enhancements caused by 60 V-broken ribs are higher than those of 90 continuous ribs. The effect of pitch to the rib height ratio (P/e) is not significant for channel with 60 V-broken ribs for a given rib height to hydraulic diameter ratio (e/D = 0.0625). (author)

  14. A solution to reducing insertion loss and achieving high sidelobe rejection for wavelet transform and reconstruction processor using SAW devices

    NASA Astrophysics Data System (ADS)

    Jiang, Hua; Lu, Wenke; Zhang, Guoan; Xie, Zhengguang

    2013-02-01

    An arbitrary wavelet transform and reconstruction processor is composed of multiple single-scale wavelet transform devices (SSWTDs) with different scales. For improving the performance of the processor using surface acoustic wave (SAW) devices, this research investigates how to reduce the insertion loss (IL) and achieve a high sidelobe rejection. To reduce the triple transit echo (TTE) and to achieve a high signal-noise ratio (SNR), the structure of the SSWTD consists of two electrode-widths-controlled (EWC) single phase unidirectional transducers (SPUDTs). In the propagation process of the SAW, the unidirectional characteristic of the new structure reduces the bidirectional loss of the entire device. In addition, to enlarge the fractional bandwidth and the sidelobe rejection, the internal structure of the SSWTD uses an input apodized transducer according to the envelope of the Morlet wavelet function as well as an output withdrawal weighting transducer. In this paper, we present a SSWTD for scale 2-2 as an example to illustrate the design method and experimental results. The new device is fabricated on 128 rotated YX-cut lithium niobate (Y128X-LiNbO3) with the electromechanical coupling coefficient k2 = 5.5% and the SAW velocity 3992 m/s. We get the experimental frequency response with the center frequency 68.14 MHz, the minimum IL -9.96 dB, the fractional bandwidth 3.3%, the maximum passband ripples 0.4 dB and the sidelobe rejection greater than 40 dB. The proposed method and structure can be extended to an arbitrary SSWTD. The experimental results confirm that the performance of the wavelet transform and reconstruction processor can be improved by the proposed solution.

  15. Dynamics of vegetation and soils of oak/saw palmetto scrub after fire: Observations from permanent transects

    NASA Technical Reports Server (NTRS)

    Schmalzer, Paul A.; Hinkle, G. Ross

    1991-01-01

    Ten permanent 15 m transects previously established in two oak/saw palmetto scrub stands burned in December 1986, while two transects remained unburned. Vegetation in the greater than 0.5 m and the less than 0.5 m layers on these transects was sampled at 6, 12, 18, 24, and 36 months postburn and determined structural features of the vegetation (height, percent bare ground, total cover). The vegetation data were analyzed from each sampling by height layer using detrended correspondence analysis ordination. Vegetation data for the greater than 0.5 m layer for the entire time sequence were combined and analyzed using detrended correspondence analysis ordination. Soils were sampled at 6, 12, 18, and 24 months postburn and analyzed for pH, conductivity, organic matter, exchangeable cations (Ca, Mg, K, Na), NO3-N, NH4-N, Al, available metals (Cu, Fe, Mn, Zn), and PO4-P. Shrub species recovered at different rates postfire with saw palmetto reestablishing cover greater than 0.5 m within one year, but the scrub oaks had not returned to preburn cover greater than 0.5 m in 3 years after the fire. These differences in growth rates resulted in dominance shifts after the fire with saw palmetto increasing relative to the scrub oaks. Overall changes in species richness were minor, although changes occurred in species richness by height layers due to different growth rates. Soils of well drained and poorly drained sites differed markedly. Soil responses to the fire appeared minor. Soil pH increased at 6 and 12 months postfire; calcium increased at 6 months postburn. Nitrate-nitrogen increased at 12 months postburn. Low values of conductivity, PO4-P, Mg, K, Na, and Fe at 12 months postburn may be related to heavy rainfall the preceding month. Seasonal variability in some soil parameters appeared to occur.

  16. Laboratory evaluation to reduce respirable crystalline silica dust when cutting concrete roofing tiles using a masonry saw.

    PubMed

    Carlo, Rebecca V; Sheehy, John; Feng, H Amy; Sieber, William K

    2010-04-01

    Respirable crystalline silica dust exposure in residential roofers is a recognized hazard resulting from cutting concrete roofing tiles. Roofers cutting tiles using masonry saws can be exposed to high concentrations of respirable dust. Silica exposures remain a serious threat for nearly two million U.S. construction workers. Although it is well established that respiratory diseases associated with exposure to silica dust are preventable, they continue to occur and cause disability or death. The effectiveness of both a commercially available local exhaust ventilation (LEV) system and a water suppression system in reducing silica dust was evaluated separately. The LEV system exhausted 0.24, 0.13, or 0.12 m(3)/sec of dust laden air, while the water suppression system supplied 0.13, 0.06, 0.03, or 0.02 L/sec of water to the saw blade. Using a randomized block design, implemented under laboratory conditions, the aforementioned conditions were evaluated independently on two types of concrete roofing tiles (s-shape and flat) using the same saw and blade. Each engineering control (LEV or water suppression) was replicated eight times, or four times for each type of tile. Analysis of variance was performed by comparing the mean airborne respirable dust concentrations generated during each run and engineering control treatment. The use of water controls and ventilation controls compared with the "no control" treatment resulted in a statistically significant (p < 0.05) reduction of mean respirable dust concentrations generated per tile cut. The percent reduction for respirable dust concentrations was 99% for the water control and 91% for the LEV. Results suggest that water is an effective method for reducing crystalline silica exposures. However, water damage potential, surface discolorations, cleanup, slip hazards, and other requirements may make the use of water problematic in many situations. Concerns with implementing an LEV system to control silica dust exposures include sufficient capture velocity, additional weight of the saw with the LEV system, electricity connections, and cost of air handling unit. PMID:20169490

  17. Effect of particle bombardment on the orientation and the residual stress of sputtered AlN films for SAW devices.

    PubMed

    Iborra, Enrique; Clement, Marta; Sangrador, Jess; Sanz-Hervs, Alfredo; Vergara, Luca; Aguilar, Miguel

    2004-03-01

    We present a study of the effect of particle bombardment on the preferred orientation and the residual stress of polycrystalline aluminum nitride (AlN) thin films for surface acoustic wave (SAW) applications. Films were deposited on silicon (100) substrates by radio frequency (RF) sputtering of an aluminum target in an argon and nitrogen gas mixture. The main deposition parameters were changed as follows: the total pressure from 4 mTorr to 11 mTorr, the N2 content in the gas mixture from 20% to 80%, and the substrate self-bias voltage from -10 V to -30 V. If a sufficiently high negative substrate self-bias voltage is induced, (00.2)-oriented films are obtained over the full ranges of pressure and N2 content. Such films have values of residual stress ranging from -3 GPa to +1 GPa, depending on the deposition conditions. Our results suggest that the energy of the Ar ions colliding with the substrate controls the preferred orientation of the films, whereas the directionality of the ions (for the same energy) is the main factor determining the residual stress. To demonstrate the suitability of our material for the intended application, SAW filters with good electroacoustic response have been fabricated using AlN thin films with optimized (00.2) orientation and controlled residual stress. PMID:15128222

  18. Rectified cell migration on saw-like micro-elastically patterned hydrogels with asymmetric gradient ratchet teeth.

    PubMed

    Kidoaki, Satoru; Sakashita, Hiroyuki

    2013-01-01

    To control cell motility is one of the essential technologies for biomedical engineering. To establish a methodology of the surface design of elastic substrate to control the long-range cell movements, here we report a sophisticated cell culture hydrogel with a micro-elastically patterned surface that allows long-range durotaxis. This hydrogel has a saw-like pattern with asymmetric gradient ratchet teeth, and rectifies random cell movements. Durotaxis only occurs at boundaries in which the gradient strength of elasticity is above a threshold level. Consequently, in gels with unit teeth patterns, durotaxis should only occur at the sides of the teeth in which the gradient strength of elasticity is above this threshold level. Therefore, such gels are expected to support the long-range biased movement of cells via a mechanism similar to the Feynman-Smoluchowski ratchet, i.e., rectified cell migration. The present study verifies this working hypothesis by using photolithographic microelasticity patterning of photocurable gelatin gels. Gels in which each teeth unit was 100-120 m wide with a ratio of ascending:descending elasticity gradient of 1:2 and a peak elasticity of ca. 100 kPa supported the efficient rectified migration of 3T3 fibroblast cells. In addition, long-range cell migration was most efficient when soft lanes were introduced perpendicular to the saw-like patterns. This study demonstrates that asymmetric elasticity gradient patterning of cell culture gels is a versatile means of manipulating cell motility. PMID:24147112

  19. [Confusing injury findings in a suicidal gunshot fired to the chest from a carbine with a sawed-off barrel].

    PubMed

    Perdekamp, Markus Grosse; Bohnert, Michael; Braunwarth, Roland; Pollak, Stefan

    2006-01-01

    The stellate bullet entrance wound is one of the facultative features of a contact shot. For the formation of a star-shaped wound two factors are of special importance: first, an extensive bony support underlying the skin in the entrance region, and second, a strong propellant charge of the cartridge fired. Contact shots to the precordial region usually do not cause stellate entrance wounds, even if high-powered rifle ammunition is used. In the reported case, an injury pattern was observed that was not in line with normal findings and seemed confusing at first. Following a suicidal gunshot to the chest from a sawed-off carbine 98a (cal. 8 x 57 Js), a 4.5 cm wide, gaping bullet entrance wound with radiating tears was found. Instead of the usual pocket, the anterior thoracic wall showed a fist-sized area of destruction with extensive undermining of the subcutis. Not far from the entrance hole, a rib fragment had become displaced retrogradely thus perforating the skin from the inside out. The unusual pattern of findings could be explained by the fact that the barrel had been sawed off: as a result of this manipulation, a considerable part of the propellant charge had been converted outside the barrel, i.e. in the initial section of the bullet path. PMID:16529177

  20. Highly sensitive room-temperature surface acoustic wave (SAW) ammonia sensors based on Co₃O₄/SiO₂ composite films.

    PubMed

    Tang, Yong-Liang; Li, Zhi-Jie; Ma, Jin-Yi; Su, Hai-Qiao; Guo, Yuan-Jun; Wang, Lu; Du, Bo; Chen, Jia-Jun; Zhou, Weilie; Yu, Qing-Kai; Zu, Xiao-Tao

    2014-09-15

    Surface acoustic wave (SAW) sensors based on Co3O4/SiO2 composite sensing films for ammonia detection were investigated at room temperature. The Co3O4/SiO2 composite films were deposited onto ST-cut quartz SAW resonators by a sol-gel method. SEM and AFM characterizations showed that the films had porous structures. The existence of SiO2 was found to enhance the ammonia sensing property of the sensor significantly. The sensor based on a Co3O4/SiO2 composite film, with 50% Co3O4 loading, which had the highest RMS value (3.72), showed the best sensing property. It exhibited a positive frequency shift of 3500 Hz to 1 ppm ammonia as well as excellent selectivity, stability and reproducibility at room temperature. Moreover, a 37% decrease in the conductance of the composite film as well as a positive frequency shift of 12,500 Hz were observed when the sensor was exposed to 20 ppm ammonia, indicating the positive frequency shift was derived from the decrease in film conductance. PMID:25151235

  1. Pulse mode shear horizontal-surface acoustic wave (SH-SAW) system for liquid based sensing applications.

    PubMed

    Martin, Fabrice; Newton, Michael I; McHale, Glen; Melzak, Kathryn A; Gizeli, Electra

    2004-01-15

    In this work, we describe a novel pulse mode shear horizontal-surface acoustic wave (SH-SAW) polymer coated biosensor that monitors rapid changes in both amplitude and phase. The SH-SAW sensors were fabricated on 36 degrees rotated Y-cut X propagating lithium tantalate (36 YX.LT). The sensitivity of the device to both mass loading and visco-elastic effects may be increased by using a thin guiding layer of cross-linked polymer. Two acoustic modes are excited by the electrodes in this crystalline direction. Metallisation of the propagation path of the 36 YX.LT devices allows the two modes to be discriminated. Successive polymer coatings resulted in the observation of resonant conditions in both modes as the layer thickness was increased. Using the 36 YX.LT devices, we have investigated the application of a novel pulse mode system by sensing a sequence of deposition and removal of a biological layer consisting of vesicles of the phospholipid POPC. A continuous wave system was used to verify the accuracy of the pulse mode system by sensing a series of poly(ethylene glycol) (PEG) solutions. The data clearly demonstrates the ability of the 36 YX.LT pulse mode system to provide rapid measurements of both amplitude and phase for biosensing applications. PMID:14683647

  2. Specific targeting of ultrasound contrast agent (USCA) for diagnostic application: an in vitro feasibility study based on SAW biosensor.

    PubMed

    Joseph, Shiba; Gronewold, Thomas Marten Arnold; Schlensog, Marc Dominic; Olbrich, Carsten; Quandt, Eckhard; Famulok, Michael; Schirner, Michael

    2005-03-15

    The present study described a new strategy to examine the interaction between the targeted ultrasound contrast agent (USCA) and its target under flow conditions with a surface acoustic wave (SAW) transducer. The sensing principle is based on the measurement of the phase change on the sensing element upon the binding of specific biomolecules. Love-wave biosensor array was consisting of sensor elements and reference elements. The sensor elements have been prepared by coating the sensor surface with tumor marker EDB-fibronectin by means of SAM technique and carbodiimide chemistry. Reference elements were left blank or coated with fibronectin and used to eliminate thermal drift, unspecific binding, and turbulence from injection of liquids by calculating the differential phase shift with respect to the sensor elements. The binding of targeted USCA to the sensor surface was constantly recorded by monitoring the phase shift on the sensor element. The binding of targeted USCA generated a high phase shift on the sensor elements, but almost no change on the reference elements. Control experiments using non-targeted and isotype-targeted USCA confirmed the specificity of binding due to anti-EDB-fibronectin scFv-antibody-fragment-EDB-fibronectin antigen interaction. The suitability of the SAW technique to monitor the specific binding behavior of targeted micron-sized USCA in real time has been well established. PMID:15681200

  3. INTERNATIONAL UNION OF OPERATING ENGINEERS NATIONAL HAZMAT PROGRAM - MILWAUKEE WORM DRIVE CIRCULAR SAW OENHP{number_sign}: 2001-02, VERSION A

    SciTech Connect

    Unknown

    2002-01-05

    Florida International University's (FIU) Hemispheric Center for Environmental Technology (HCET) evaluated five saws for their effectiveness in cutting specially prepared fiberglass-reinforced plywood crates. These crates were built as surrogates for crates that presently hold radioactively contaminated glove boxes at the Department of Energy's (DOE) Los Alamos facility. The Milwaukee worm drive circular saw was assessed on August 14, 2001. During the FIU test of efficacy, a team from the Operating Engineers National Hazmat Program (OENHP) evaluated the occupational safety and health issues associated with this technology. The Milwaukee worm drive circular saw is a hand-held tool with a 7 1/4-inch diameter circular blade for cutting wood. The saw contains a fixed upper and a retractable lower blade guard to prevent access to the blade during use. The unit is operated with an on/off guarded trigger switch; and is supported with a handgrip mounted on top of the saw. An adjustable lever sets the depth of cut. The retractable blade guard permits blind or plunge cuts and protects from blade access during shutdown and blade coast. Kickback, the sudden reaction to a pinched blade, is possible when using this saw and could cause the saw to lift up and out of the work piece toward the operator. Proper work position and firm control of the saw minimizes the potential for a sprain or strain. Care needs to be exercised to support the work piece properly and to not force the tool. Personal noise sampling indicated that one worker was near the Occupational Safety and Health Administration's (OSHA) Action Level of 85 decibels (dBA) while the other was at the Action Level with time-weighted averages (TWA's) of 82.7 and 84.6 dBA, respectively. These data are not entirely representative as they were gathered during a simulation and not at the actual worksite. Additional sampling should be conducted on-site, but the workers should wear hearing protection until it is determined that it is no longer necessary. Air sampling was performed while the workers dismantled the fiberglass-reinforced crates. The total nuisance dust sample for the Milwaukee circular saw was 36.07 milligrams per cubic meter (mg/m{sup 3}), which is much higher than the OSHA Permissible Exposure Limit (PEL) of 15 mg/m{sup 3} and the American Conference of Governmental Industrial Hygienists' (ACGIH) Threshold Limit Value (TLV) of 10 mg/m{sup 3}. Galson Laboratories considered the fiber analysis void due to the overloading of the filter. The PEL for fiberglass is 1 fiber per cubic centimeter (f/cc).

  4. Suppression of transverse mode responses in ultra-wideband SAW resonators fabricated on a Cu-grating/15 degrees YX-linbO3 structure.

    PubMed

    Omori, Tatsuya; Matsuda, Kenji; Yokoyama, Naofumi; Hashimoto, Ken-ya; Yamaguchi, Masatsune

    2007-10-01

    This paper discusses a technique to suppress spurious transverse mode responses appearing in ultra-wideband SAW resonators fabricated on a Cu-grating/15 degrees YX-LiNbO3 structure. The basic idea of the technique is inserting length- and width-weighted dummy electrodes between a bus-bar and interdigital electrodes. For practical device design, an analysis was made to show how the profile (field distribution) of both dominant and spurious transverse modes depends on the length and width (equivalent to SAW velocity) of the dummy electrodes. IDT-type SAW resonators were fabricated on a Cu-grating/15 degrees YX-LiNbO3 structure using the length- and width-weighted dummy electrodes. The experimental results were in good agreement with the theoretical analysis and prediction, showing that the proposed technique is effective in suppressing the spurious responses caused by the transverse modes. PMID:18019230

  5. Performance, kinetics, and equilibrium of methylene blue adsorption on biochar derived from eucalyptus saw dust modified with citric, tartaric, and acetic acids.

    PubMed

    Sun, Lei; Chen, Dongmei; Wan, Shungang; Yu, Zebin

    2015-12-01

    Biochar derived from eucalyptus saw dust modified with citric, tartaric, and acetic acids at low temperatures was utilized as adsorbent to remove methylene blue (MB) from aqueous solutions. Fourier transform infrared spectroscopy analysis showed that the carboxyl group was introduced on the biochar surface. Adsorption experiment data indicated that eucalyptus saw dust modified with citric acid showed higher MB adsorption efficiency than that modified with tartaric and acetic acids. Pseudo-second-order kinetics was the most suitable model for describing MB adsorption on biochar compared with pseudo-first-order, Elovich, and intraparticle diffusion models. The calculated values of ?G(0) and ?H(0) indicated the spontaneous and endothermic nature of the adsorption process. MB adsorption on biochar followed the Langmuir isotherm. The maximum adsorption capacities for eucalyptus saw dust modified with citric, tartaric, and acetic acids were 178.57, 99.01, and 29.94 mg g(-1), respectively, at 35C. PMID:26402873

  6. Development of Methods of Producing Large Areas of Silicon Sheet by the Slicing of Silicon Ingots Using Inside Diameter (I.D.) Saws

    NASA Technical Reports Server (NTRS)

    Aharonyan, P.

    1979-01-01

    Methods of producing large areas of silicon sheets were developed by using inside diameter (I.D.) saws to slice silicon ingots. A 16 inch automated I.D. slicing machine was modified to accept programmable electric feed system, a crystal rotating system and a dyna-track blade monitoring and control system. The saw and accessories were used to slice 75 mm diameter single crystal silicon ingots while rotating them. The automated saw automatically recovered the wafers and loaded them into a cassette. The amount of material lost during slicing was reduced by using smaller blades than ones normally used to slice the wafers. Slicing runs on 100 mm diameter silicon is the next goal.

  7. Enhancing chemical identification efficiency by SAW sensor transients through a data enrichment and information fusion strategya simulation study

    NASA Astrophysics Data System (ADS)

    Singh, Prashant; Yadava, R. D. S.

    2013-05-01

    The paper proposes a new approach for improving the odor recognition efficiency of a surface acoustic wave (SAW) transient sensor system based on a single polymer coating. The vapor identity information is hidden in transient response shapes through dependences on specific vapor solvation and diffusion parameters in the polymer coating. The variations in the vapor exposure and purge durations and the sensor operating frequency have been used to create diversity in transient shapes via termination of the vapor-polymer equilibration process up to different stages. The transient signals were analyzed by the discrete wavelet transform using Daubechies-4 mother wavelet basis. The wavelet approximation coefficients were then processed by principal component analysis for creating feature space. The set of principal components define the vapor identity information. In an attempt to enhance vapor class separability we analyze two types of information fusion methods. In one, the sensor operation frequency is fixed and the sensing and purge durations are varied, and in the second, the sensing and purge durations are fixed and the sensor operating frequency is varied. The fusion is achieved by concatenation of discrete wavelet coefficients corresponding to various transients prior to the principal component analysis. The simulation experiments with polyisobutylene SAW sensor coating for operation frequencies over [55-160] MHz and sensing durations over [5-60] s were analyzed. The target vapors are seven volatile organics: chloroform, chlorobenzene, o-dichlorobenzene, n-heptane, toluene, n-hexane and n-octane whose concentrations were varied over [10-100] ppm. The simulation data were generated using a SAW sensor transient response model that incorporates the viscoelastic effects due to polymer coating and an additive noise source in the output. The analysis reveals that: (i) in single transient analysis the class separability increases with sensing duration for a given frequency of operation, and also with frequency for a given sensing duration, and (ii) the information fusion based on both the multiple sensing cycles and the multiple sensing frequencies enhances the class separability by nearly an order of magnitude.

  8. Chemical class specificity using self-assembled monolayers on SAW devices: Effects of adsorption time and substrate grain size

    SciTech Connect

    Thomas, R.C.; Ricco, A.J.; DiRubio, C.R.; Yang, H.C.; Crooks, R.M.

    1997-07-01

    The authors report selectivity and sensitivity for 97-MHz SAW (surface acoustic wave) sensors functionalized with (COO{sup {minus}}){sub 2}/Cu{sup 2+}-terminated, organomercaptan-based, self-assembled monolayers (SAMs). Responses were obtained as a function of SAM formation time on thin Au films of controlled grain size. The authors find that the SAM films (1) preferentially adsorb classes of organic analytes according to simple chemical interaction concepts, (2) reversibly adsorb multilayers of some analytes well below their saturation vapor pressure, (3) adsorb more diisopropylmethylphosphonate (DIMP) at a given partial pressure as SAM solution-phase adsorption time increases, and (4) adsorb more DIMP at a given partial pressure as the grain size of the supporting Au film decreases.

  9. Staircase and saw-tooth field emission steps from nanopatterned n-type GaSb surfaces

    SciTech Connect

    Kildemo, M.; Levinsen, Y. Inntjore; Le Roy, S.; Soenderga ring rd, E.

    2009-09-15

    High resolution field emission experiments from nanopatterned GaSb surfaces consisting of densely packed nanocones prepared by low ion-beam-energy sputtering are presented. Both uncovered and metal-covered nanopatterned surfaces were studied. Surprisingly, the field emission takes place by regular steps in the field emitted current. Depending on the field, the steps are either regular, flat, plateaus, or saw-tooth shaped. To the author's knowledge, this is the first time that such results have been reported. Each discrete jump in the field emission may be understood in terms of resonant tunneling through an extended surface space charge region in an n-type, high aspect ratio, single GaSb nanocone. The staircase shape may be understood from the spatial distribution of the aspect ratio of the cones.

  10. Single-monolayer in situ modulus measurements using a SAW device: Photocrosslinking of a diacetylenic thiol-based monolayer

    SciTech Connect

    Ricco, A.J.; Staton, A.W.; Crooks, R.M.; Kim, Taisun

    1997-10-01

    We report direct measurement of the modulus change that accompanies the crosslinking of a single molecular monolayer. We measured a change in elastic modulus of 5 x 10{sup 10} dyn/cm{sup 2} as a result of ultraviolet-induced photocrosslinking of a single surface-confined monolayer of the conjugated diacetylenic thiol HS(CH{sub 2}){sub 10}C{triple_bond}CC{triple_bond}C(CH{sub 2}){sub 10}COOH, designated {open_quotes}DAT{close_quotes} hereafter. The modulus measurement was made on a monolayer of DAT chemisorbed upon a gold film on the surface of a 97-MHz ST-quartz surface acoustic wave delay line. The ratio of the changes recorded in SAW velocity and attenuation, approximately 4:1, suggests that the measured effect is mainly a change in the elastic (real) component of the complex shear modulus, viscous changes playing a lesser role. In relation to typical polymer modulus values, the change of 5 x 10{sup 10} dyn/cm{sup 2} is consistent with a change from a rubbery material (G{prime} {approximately} 10{sup 7} - 10{sup 8} dyn/cm{sup 2}) to a fairly rigid, glassy material (G{prime} {approximately} 10{sup 10} dyn/cm{sup 2}), reasonable for comparison of the monolayer in its as-adsorbed and crosslinked forms. This report of the direct SAW-based measurement of the modulus change associated with the crosslinking of a single molecular monolayer is complementary to and consistent with previous in-situ measurements of this process using thickness-shear mode resonators.

  11. Evaluation of surgically assisted rapid maxillary expansion with piezosurgery versus oscillating saw and chisel osteotomy - a randomized prospective trial

    PubMed Central

    2013-01-01

    Background Ultrasonic bone-cutting surgery has been introduced as a feasible alternative to the conventional sharp instruments used in craniomaxillofacial surgery because of its precision and safety. The piezosurgery medical device allows the efficient cutting of mineralized tissues with minimal trauma to soft tissues. Piezoelectric osteotome has found its role in surgically assisted rapid maxillary expansion (SARME), a procedure well established to correct transverse maxillary discrepancies. The advantages include minimal risk to critical anatomic structures. The purpose of this clinical comparative study (CIS 2007-237-M) was to present the advantages of the piezoelectric cut as a minimally invasive device in surgically assisted, rapid maxillary expansion by protecting the maxillary sinus mucosal lining. Methods Thirty patients (18 females and 12 males) at the age of 18 to 54 underwent a surgically assisted palatal expansion of the maxilla with a combined orthodontic and surgical approach. The patients were randomly divided into two separate treatment groups. While Group 1 received conventional surgery using an oscillating saw, Group 2 was treated with piezosurgery. The following parameters were examined: blood pressure, blood values, required medication, bleeding level in the maxillary sinus, duration of inpatient stay, duration of surgery and height of body temperature. Results The results displayed no statistically significant differences between the two groups regarding laboratory blood values and inpatient stay. The duration of surgery revealed a significant discrepancy. Deploying piezosurgery took the surgeon an average of 10minutes longer than working with a conventional-saw technique. However, the observation of the bleeding level in the paranasal sinus presented a major and statistically significant advantage of piezosurgery: on average the bleeding level was one category above the one of the remaining patients. Conclusion This method of piezoelectric surgery with all its advantages is going to replace many conventional operating procedures in oral and maxillofacial surgery. Trial registration CIS 2007-237-M PMID:23414112

  12. Evaluation of a gas chromatograph with a novel surface acoustic wave detector (SAW GC) for screening of volatile organic compounds in Hanford waste tank samples

    SciTech Connect

    Lockrem, L.L.

    1998-01-12

    A novel instrument, a gas chromatograph with a Surface Acoustic Wave Detector (SAW GC), was evaluated for the screening of organic compounds in Hanford tank headspace vapors. Calibration data were developed for the most common organic compounds, and the accuracy and precision were measured with a certified standard. The instrument was tested with headspace samples collected from seven Hanford waste tanks.

  13. Approaching sub-50 nanoradian measurements by reducing the saw-tooth deviation of the autocollimator in the Nano-Optic-Measuring Machine

    NASA Astrophysics Data System (ADS)

    Qian, Shinan; Geckeler, Ralf D.; Just, Andreas; Idir, Mourad; Wu, Xuehui

    2015-06-01

    Since the development of the Nano-Optic-Measuring Machine (NOM), the accuracy of measuring the profile of an optical surface has been enhanced to the 100-nrad rms level or better. However, to update the accuracy of the NOM system to sub-50 nrad rms, the large saw-tooth deviation (269 nrad rms) of an existing electronic autocollimator, the Elcomat 3000/8, must be resolved. We carried out simulations to assess the saw-tooth-like deviation. We developed a method for setting readings to reduce the deviation to sub-50 nrad rms, suitable for testing plane mirrors. With this method, we found that all the tests conducted in a slowly rising section of the saw-tooth show a small deviation of 28.8 to <40 nrad rms. We also developed a dense-measurement method and an integer-period method to lower the saw-tooth deviation during tests of sphere mirrors. Further research is necessary for formulating a precise test for a spherical mirror. We present a series of test results from our experiments that verify the value of the improvements we made.

  14. Fatty acid analysis of saw palmetto (Serenoa repens) and pygeum (Prunus africanum) in dietary supplements by mass spectrometry in the selected ion monitoring mode

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Saw palmetto and pygeum are natural products commonly used in dietary supplements for the treatment of enlarged prostate glands. These plant materials are rich in fatty acids, and the fatty acid compositions of both plants are similar. The goal of this study was to develop a gas chromatography-mass ...

  15. The effect of purification of single-walled carbon nanotube bundles on the alcohol sensitivity of nanocomposite Langmuir Blodgett films for SAW sensing applications

    NASA Astrophysics Data System (ADS)

    Penza, M.; Tagliente, M. A.; Aversa, P.; Re, M.; Cassano, G.

    2007-05-01

    HiPco (high-pressure CO dissociation process) single-walled carbon nanotube (SWCNT) bundles containing Fe particles were purified in a two-step purification process by thermal annealing in oxygen and post-treatment in HCl. Nanocomposite films of pristine and purified SWCNTs embedded in an organic matrix of cadmium arachidate (CdA) were prepared by a Langmuir-Blodgett (LB) molecular engineering technique with a fixed weight filler content of 75 wt% onto a surface acoustic wave (SAW) transducer operating as an oscillator at a frequency of 433 MHz. The raw and purified samples were characterized at various stages of the purification process using thermogravimetric analysis (TGA), high-resolution transmission electron microscopy (HR-TEM), along with energy-dispersive x-ray spectroscopy (EDS), field emission scanning electron microscopy (FE-SEM) and x-ray diffraction (XRD). Functional characterizations of the SWCNT-nanocomposite-based SAW sensors were investigated towards methanol, isopropanol and ethanol, and demonstrated high sensitivity, reversibility, fast response and ppm level detection at room temperature. Results indicate that the sensitivity of the SAW sensors based on a nanocomposite film of oxygen-annealed SWCNTs is enhanced to the alcohols tested at room temperature. Purification of the SWCNTs in the nanocomposite film affects the SAW sensitivity to alcohol by modulating the sensing properties. The sensing mechanisms are analysed and discussed.

  16. Facile synthesis of silver nano/micro-ribbons or saws assisted by polyoxomolybdate as mediator agent and vanadium(IV) as reducing agent.

    PubMed

    Marchal-Roch, Catherine; Mayer, Cdric R; Michel, Aude; Dumas, Eddy; Liu, Feng-Xian; Scheresse, Francis

    2007-09-28

    Original and effective syntheses of crystalline silver wires and saw bundles, using reduced Keggin polyoxomolybdovanadate (POM) as mediator and reducing agent, were performed in acetonitrile at room temperature; several parameters influencing the final silver 1D-structures, with micrometric length and nanometric thickness, were varied: the nature of the POM, silver salts, vanadium(iv) source and the mild conditions. PMID:17851616

  17. Muscle activity and spine load during anterior chain whole body linkage exercises: the body saw, hanging leg raise and walkout from a push-up.

    PubMed

    McGill, Stuart; Andersen, Jordan; Cannon, Jordan

    2015-01-01

    This study examined anterior chain whole body linkage exercises, namely the body saw, hanging leg raise and walkout from a push-up. Investigation of these exercises focused on which particular muscles were challenged and the magnitude of the resulting spine load. Fourteen males performed the exercises while muscle activity, external force and 3D body segment motion were recorded. A sophisticated and anatomically detailed 3D model used muscle activity and body segment kinematics to estimate muscle force, and thus sensitivity to each individual's choice of motor control for each task. Gradations of muscle activity and spine load characteristics were observed across tasks. On average, the hanging straight leg raise created approximately 3000 N of spine compression while the body saw created less than 2500 N. The hanging straight leg raise created the highest challenge to the abdominal wall (>130% MVC in rectus abdominis, 88% MVC in external oblique). The body saw resulted in almost 140% MVC activation of the serratus anterior. All other exercises produced substantial abdominal challenge, although the body saw did so in the most spine conserving way. These findings, along with consideration of an individual's injury history, training goals and current fitness level, should assist in exercise choice and programme design. PMID:25111163

  18. Identification and Affinity-Quantification of ß-Amyloid and α-Synuclein Polypeptides Using On-Line SAW-Biosensor-Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Slamnoiu, Stefan; Vlad, Camelia; Stumbaum, Mihaela; Moise, Adrian; Lindner, Kathrin; Engel, Nicole; Vilanova, Mar; Diaz, Mireia; Karreman, Christiaan; Leist, Marcel; Ciossek, Thomas; Hengerer, Bastian; Vilaseca, Marta; Przybylski, Michael

    2014-08-01

    Bioaffinity analysis using a variety of biosensors has become an established tool for detection and quantification of biomolecular interactions. Biosensors, however, are generally limited by the lack of chemical structure information of affinity-bound ligands. On-line bioaffinity-mass spectrometry using a surface-acoustic wave biosensor (SAW-MS) is a new combination providing the simultaneous affinity detection, quantification, and mass spectrometric structural characterization of ligands. We describe here an on-line SAW-MS combination for direct identification and affinity determination, using a new interface for MS of the affinity-isolated ligand eluate. Key element of the SAW-MS combination is a microfluidic interface that integrates affinity-isolation on a gold chip, in-situ sample concentration, and desalting with a microcolumn for MS of the ligand eluate from the biosensor. Suitable MS- acquisition software has been developed that provides coupling of the SAW-MS interface to a Bruker Daltonics ion trap-MS, FTICR-MS, and Waters Synapt-QTOF- MS systems. Applications are presented for mass spectrometric identifications and affinity (KD) determinations of the neurodegenerative polypeptides, ß-amyloid (Aß), and pathophysiological and physiological synucleins (α- and ß-synucleins), two key polypeptide systems for Alzheimer's disease and Parkinson's disease, respectively. Moreover, first in vivo applications of αSyn polypeptides from brain homogenate show the feasibility of on-line affinity-MS to the direct analysis of biological material. These results demonstrate on-line SAW-bioaffinity-MS as a powerful tool for structural and quantitative analysis of biopolymer interactions.

  19. Identification and affinity-quantification of -amyloid and ?-synuclein polypeptides using on-line SAW-biosensor-mass spectrometry.

    PubMed

    Slamnoiu, Stefan; Vlad, Camelia; Stumbaum, Mihaela; Moise, Adrian; Lindner, Kathrin; Engel, Nicole; Vilanova, Mar; Diaz, Mireia; Karreman, Christiaan; Leist, Marcel; Ciossek, Thomas; Hengerer, Bastian; Vilaseca, Marta; Przybylski, Michael

    2014-08-01

    Bioaffinity analysis using a variety of biosensors has become an established tool for detection and quantification of biomolecular interactions. Biosensors, however, are generally limited by the lack of chemical structure information of affinity-bound ligands. On-line bioaffinity-mass spectrometry using a surface-acoustic wave biosensor (SAW-MS) is a new combination providing the simultaneous affinity detection, quantification, and mass spectrometric structural characterization of ligands. We describe here an on-line SAW-MS combination for direct identification and affinity determination, using a new interface for MS of the affinity-isolated ligand eluate. Key element of the SAW-MS combination is a microfluidic interface that integrates affinity-isolation on a gold chip, in-situ sample concentration, and desalting with a microcolumn for MS of the ligand eluate from the biosensor. Suitable MS-acquisition software has been developed that provides coupling of the SAW-MS interface to a Bruker Daltonics ion trap-MS, FTICR-MS, and Waters Synapt-QTOF- MS systems. Applications are presented for mass spectrometric identifications and affinity (K(D)) determinations of the neurodegenerative polypeptides, -amyloid (A), and pathophysiological and physiological synucleins (?- and -synucleins), two key polypeptide systems for Alzheimer's disease and Parkinson's disease, respectively. Moreover, first in vivo applications of ?Syn polypeptides from brain homogenate show the feasibility of on-line affinity-MS to the direct analysis of biological material. These results demonstrate on-line SAW-bioaffinity-MS as a powerful tool for structural and quantitative analysis of biopolymer interactions. PMID:24845351

  20. Detection of cellular damage by hydrogen peroxide using SV40-T2 cells on shear horizontal surface acoustic wave (SH-SAW) sensor.

    PubMed

    Higashiyama, Takumi; Katsuyama, Akihiro; Otori, Hideki; Kamimura, Toru; Uehara, Atsushi; Kainuma, Miho; Takumi, Ryo; Kudo, Yukako; Ebina, Masayuki; Mochitate, Katsumi; Kon, Tasuku; Furuya, Yasubumi; Kikuchi, Hideaki

    2014-08-01

    The rat lung epithelial cell line SV40-T2 was used to develop a cellular biosensing system to assay for environmental toxicants. The novel approach on which this system is based involves direct attachment of cultured rat or human cells onto a cell-adhesive matrix on the device through which shear horizontal surface acoustic waves (SH-SAW) are transmitted using 50 MHz SAW resonator. This novel design enables sensitive monitoring of changes of the electrophysical characteristics of cells, such as their conductivity and relative permittivity. A time-dependent change of phase of SAW and change of insertion loss (change of amplitude) were observed when the cells were treated with 0.5 or 1.0 mM H2O2. The change of insertion loss was biphasic, with an early phase (1-3 h) and a late phase (3-6 h). The late phase coincided with the destruction of cell-cell tight junctions detected by measurement of the transepithelial electrical resistance and paracellular permeability; in contrast, the early phase coincided with the destruction of intracellular actin filaments by H2O2. The early-phase effect of H2O2 on phase shift may be attributable to the change of intracellular permittivity by a change of cellular polarity. Immunofluorescence microscopy showed the disappearance of zonula occludens protein 1 from the region of cell-cell contact. These results suggest the correlation between the change of insertion loss as an SAW parameter and the destruction of tight junctions of the cells on the SH-SAW device in the late phase. PMID:24835005

  1. Saw1 localizes to repair sites but is not required for recruitment of Rad10 to repair intermediates bearing short non-homologous 3' flaps during single-strand annealing in S. cerevisiae.

    PubMed

    Mardirosian, Melina; Nalbandyan, Linette; Miller, Aaron D; Phan, Claire; Kelson, Eric P; Fischhaber, Paula L

    2016-01-01

    SAW1 is required for efficient removal by the Rad1-Rad10 nuclease of 3' non-homologous DNA ends (flaps) formed as intermediates during two modes of double-strand break (DSB) repair in S. cerevisiae, single-strand annealing (SSA) and synthesis-dependent strand annealing. Saw1 was shown in vitro to bind flaps with high affinity, but displayed diminished affinity when flaps were short (<30 deoxynucleotides [nt]), consistent with it not being required for short flap cleavage. Accordingly, this study, using in vivo fluorescence microscopy showed that SAW1 was not required for recruitment of Rad10-YFP to DNA DSBs during their repair by SSA when the flaps were ~10nt. In contrast, recruitment of Rad10-YFP to DSBs when flaps were ~500nt did require SAW1 in G1 phase of cell cycle. Interestingly, we observed a substantial increase in colocalization of Saw1-CFP and Rad10-YFP at DSBs when short flaps were formed during repair, especially in G1, indicating significant recruitment of Saw1 despite there being no requirement for Saw1 to recruit Rad10. Saw1-CFP was seldom observed at DSBs without Rad10-YFP. Together, these results support a model in which Saw1 and Rad1-Rad10 are recruited as a complex to short and long flaps in all phases of cell cycle, but that Saw1 is only required for recruitment of Rad1-Rad10 to DSBs when long flaps are formed in G1. PMID:26699908

  2. A comparative study of the SSC resistance of a novel welding process IEA with SAW and MIG

    SciTech Connect

    Natividad, C. . E-mail: consnatividad@yahoo.com.mx; Salazar, M. . E-mail: salazarm@imp.mx; Espinosa-Medina, M.A.; Perez, R.

    2007-08-15

    The Stress Sulphide Cracking resistance of X65 weldments produced by Indirect Electric Arc, Submerged Arc Welding (SAW) and Metal Inert Gas (MIG) processes were evaluated in a NACE solution saturated with H{sub 2}S at 25 deg. C, 37 deg. C and 50 deg. C using Slow Strain Rate Tests (SSRT) and electrochemical measurements. Weldments produced by the Indirect Electric Arc presented the best Stress Sulphide Cracking resistance at 25 deg. C. This behavior is attributed to the microstructural modification of the weld bead from ferrite in a needlelike form to a fine grain microstructure, which was not observed at 37 deg. C and 50 deg. C. In addition, the hydrogen permeation flux increased with the temperature, this result is associated with the ferrite phase. The electrochemical results show a decrease of the trapping sites for the atomic hydrogen on this weldment. This behavior has not been observed for the other welding processes due to their microstructure (a typical columnar growth of coarse grain)

  3. Numerical simulation of operation modes in atmospheric pressure uniform barrier discharge excited by a saw-tooth voltage

    SciTech Connect

    Li Xuechen; Niu Dongying; Yin Zengqian; Fang Tongzhen; Wang Long

    2012-08-15

    The characteristics of dielectric barrier discharge excited by a saw-tooth voltage are simulated in atmospheric pressure helium based on a one-dimensional fluid model. A stepped discharge is obtained per half voltage cycle with gas gap width less than 2 mm by the simulation, which is different to the pulsed discharge excited by a sinusoidal voltage. For the stepped discharge, the plateau duration increases with increasing the voltage amplitude and decreasing the gas gap. Therefore, uniform discharge with high temporal duty ratio can be realized with small gap through increasing the voltage amplitude. The maximal densities of both electron and ion appear near the anode and the electric field is almost uniformly distributed along the gap, which indicates that the stepped discharge belongs to a Townsend mode. In contrast to the stepped discharge with small gas gap, a pulsed discharge can be obtained with large gas gap. Through analyzing the spatial density distributions of electron and ion and the electric field, the pulsed discharge is in a glow mode. The voltage-current (V-I) characteristics are analyzed for the above mentioned discharges under different gas gaps, from which the different discharge modes are verified.

  4. Noise-induced generation of saw-tooth type transitions between climate attractors and stochastic excitability of paleoclimate

    NASA Astrophysics Data System (ADS)

    Alexandrov, Dmitri V.; Bashkirtseva, Irina A.; Ryashko, Lev B.

    2015-11-01

    Motivated by important paleoclimate applications we study a three dimensional model of the Quaternary climatic variations in the presence of stochastic forcing. It is shown that the deterministic system exhibits a limit cycle and two stable system equilibria. We demonstrate that the closer paleoclimate system to its bifurcation points (lying either in its monostable or bistable zone) the smaller noise generates small or large amplitude stochastic oscillations, respectively. In the bistable zone with two stable equilibria, noise induces a complex multimodal stochastic regime with intermittency of small and large amplitude stochastic fluctuations. In the monostable zone, the small amplitude stochastic oscillations localized in the vicinity of unstable equilibrium appear along with the large amplitude oscillations near the stable limit cycle. For the analysis of these noise-induced effects, we develop the stochastic sensitivity technique and use the Mahalanobis metric in the three-dimensional case. To approximate the distribution of random trajectories in Poincare sections, we use a method of confidence ellipses. A spatial configuration of these ellipses is defined by the stochastic sensitivity and noise intensity. The glaciation/deglaciation transitions going between two polar Earth's states with the warm and cold climate become easier and quicker with increasing the noise intensity. Our stochastic analysis demonstrates a near 100 ky saw-tooth type climate self fluctuations known from paleoclimate records. In addition, the enhancement of noise intensity blurs the sharp climate cycles and reduces the glaciation-deglaciation periods of the Earth's paleoclimate.

  5. Co-pyrolysis behaviors of saw dust and Shenfu coal in drop tube furnace and fixed bed reactor.

    PubMed

    Li, Shuaidan; Chen, Xueli; Wang, Li; Liu, Aibin; Yu, Guangsuo

    2013-11-01

    Co-pyrolysis behaviors of saw dust (SD) and Shenfu bituminous coal (SF) were studied in a drop tube furnace and a fixed bed reactor at different temperatures respectively. Six different biomass/coal ratios (B:C) were used. Compared the results with the calculated value obtained by the additional behavior, CO volume yields were lower while H2, CH4, CO2, volume yields were higher. Blend char yields had a good agreement with the calculated values, and their structures remained similar with SD and SF char's. Synergy effect occurred in gaseous phase, which was mainly caused by the secondary reactions. Compared the blend char yields in the drop tube furnace with those in the fixed bed reactor, the results showed the contacting way of biomass and coal particles had little influence on char yield in co-pyrolysis process. The reactivity index of blend char achieved the minimum at B:C=40:60 and the maximum at B:C=80:20. PMID:24041762

  6. Field portable detection of VOCs using a SAW/GC system. Final report, June 21, 1994--September 21, 1996

    SciTech Connect

    Chang, F.; Staples, E.J.

    1998-06-01

    This report describes research on a fast GC vapor analysis system which uses a new type of Surface Acoustic Wave detector technology to characterize organic contamination in soil and groundwater. The project was sponsored by the Department of Energy, Morgantown Energy Technology Center, whose mission, in addition to other goals, is the development of tools and methods for characterization, remediation, and monitoring of underground environmental conditions. The research tasks were to demonstrate detectability and specificity of a Surface Acoustic Wave Gas Chromatograph (SAW/GC) to a representative number of VOC materials followed by field demonstrations of the new technology at a DOE site. All tasks of the project were successfully carried out and a fast vapor analysis system based upon a new type of Surface Acoustic Wave detector technology was developed. The prototype analyzer has the ability to characterize organic contamination in soil and groundwater at the part per billion level in less than 10 seconds. The detector is unique because it utilized an uncoated quartz crystal, contrary to current developments of using coated crystals.

  7. Nursing Homes That Increased The Proportion Of Medicare Days Saw Gains In Quality Outcomes For Long-Stay Residents.

    PubMed

    Lepore, Michael; Leland, Natalie E

    2015-12-01

    Nursing homes are increasingly providing rehabilitative care to short-stay residents under Medicare's skilled nursing facility coverage, which is much more generous than Medicaid's coverage for long-stay residents. This shift creates the potential for both beneficial and detrimental effects on outcomes for such residents. Examining nationwide facility-level nursing home data for the period 2007-10, we found that increasing the proportion of Medicare-covered patient days in a nursing home was significantly associated with improvements in the quality of the three outcomes we considered for long-stay residents. We saw significant decreases in the percentages of long-stay residents with daily pain (from 5.1percent to 3.4percent), with worsening pressure ulcers (from 2.5percent to 2.0percent), and with a decline in performing activities of daily living (from 15.9percent to 14.9percent). These findings reinforce previous research indicating that quality outcomes tend to be superior in nursing homes with greater financial resources. They also bolster arguments for financial investments in nursing homes, including increases in Medicaid payment rates, to support better care for long-stay residents. PMID:26643633

  8. The investigation of preferred orientation growth of ZnO films on the PbTiO 3-based ceramics and its application for SAW devices

    NASA Astrophysics Data System (ADS)

    Chu, Sheng-Yuan; Chen, Te-Yi; Water, Walter

    2003-10-01

    Poly-crystal ZnO films with c-axis (0 0 2) orientation have been successfully grown on the lead-based ceramic substrates by RF magnetron sputtering technique. The deposited films were characterized as a function of deposition time, argon-oxygen gas flow ratio, and RF power. Crystalline structures of the films were investigated by X-ray diffraction, scanning electron microscopy and atomic force microscopy. Highly oriented films with c-axis normal to the substrates can be obtained by depositing under a total pressure of 10 mTorr containing 50% argon and 50% oxygen and RF power of 70 W for 3 h. The phase velocity, electromechanical coupling coefficient and temperature coefficient of frequency of surface acoustic wave (SAW) device with ZnO/IDT/PT-ceramic structure were investigated. It shows that the preferred oriented ZnO film is beneficial for improving the electromechanical coupling coefficient of SAW device.

  9. Antigen-antibody selective recognition using LiTaO3 SH-SAW sensors: investigations on macromolecules effects on binding kinetic constants

    NASA Astrophysics Data System (ADS)

    Bergaoui, Y.; Zerrouki, C.; Fourati, N.; Fougnion, J. M.; Abdelghani, A.

    2011-10-01

    A gravimetric surface acoustic wave (SAW) biosensor, based on the biotin-streptavidin and antistreptavidin-streptavidin recognitions, has been carried out. A network analyser and a pulse excitation technique were used to monitor both amplitude and phase changes. The SAW biosensor presented a total selective recognition of streptavidin-antistreptavidin and HRPstreptavidin-antistreptavidin. The presence of HRP (Horseradish peroxidase) affects neither the selectivity nor the sensitivity (of order of 0.25/nM) of the biosensor, nevertheless, it causes a reduction of binding kinetics by a factor ranging between 2 to 5, as well as a diminution of antistreptavidin saturation concentration (of 40%). Results showed that equilibrium constants can be different, depending on evaluation method (from saturation values or from linear part of the output signal variation according to solution concentration).

  10. Reduction in airborne contamination levels at the 9201-5 Arc Melt sawing operation. A Y-12 Plant 1982 ALARA goal

    SciTech Connect

    Beck, D.E.; West, C.M.

    1983-02-01

    Lowering the uranium airborne contamination level at the two saws in the 9201-5 Arc Melt Area was chosen as a Y-12 Plant As-Low-As-Reasonably-Achievable (ALARA) goal for 1982. This priority was convincingly communicated to those involving by giving specific instructions to suspend saw operations any time there was evidence of a problem until that problem could be corrected. Using control charts on air flow rates into the saw enclosures and pressure drops across filters in the saw ventilation (Delta Phase I) exhaust system, it was possible to decide when filter changes or other adjustments were necessary to maintain the exhaust flow rates needed for improved airborne contamination control. The keeping of these charts, along with the actions taken on the basis of the data gathered, made it possible to meet the goal of reducing airborne contamination levels in 1982, as compared with 1981, although production in the Arc Melt Area increased significantly. These data also showed that use of one brand of filter in the prefilter system resulted in the need to change filters more frequently than when another brand was used. This fact triggered an investigation which revealed the cause for the shorter useful life of that filter and a request that only specifically approved filters be purchased for use in this system. Use of these control data also made it possible to establish that the exhaust system operated more effectively without the Roto-clone hydrostatic pecipitators because exhaust air flow was increased without reduction in filter life.

  11. Camphor sulfonic acid-doped polyaniline nanofiber-based 64o YX LiNbO3 SAW hydrogen gas sensor

    NASA Astrophysics Data System (ADS)

    Wlodarski, W.; Sadek, Abu Z.; Baker, C.; Kalantar-zadeh, K.; Kaner, R. B.; Mulcahy, Dennis

    2007-01-01

    A template-free, rapidly-mixed reaction was employed to synthesize polyaniline nanofibers using chemical oxidative polymerization of aniline. Camphor sulfonic acid (CSA) was used in the synthesis to obtain 50 nm average diameter polyaniline nanofibers. The nanofibers were deposited onto a 64 YX LiNbO 3 SAW transducer. The sensor was tested towards hydrogen (H II) gas while operating at room temperature. A fast response and recovery with high sensitivity and good repeatability were observed.

  12. Influence of spinel substrate and over-layer for enhanced SAW and AO properties with KNbO3 thin film.

    PubMed

    Nayak, Ranu; Gupta, Vinay; Sreenivas, Kondepudy

    2003-06-01

    Surface acoustic wave (SAW) propagation characteristics have been studied using modeling calculations for a potassium niobate (KNbO3) thin film-layered structure with (001) and (110) orientation on a single crystal spinel (MgAl2O4) substrate, and a spinel buffer layer on silicon. Variation in the electromechanical coupling and acoustic attenuation has been compared. A significantly high value of coupling factor (k2max = 23%) is obtained for the (001)KNbO3/spinel structure by introducing an optimum thickness of spinel over-layer for potential wide bandwidth SAW device applications. The dispersion characteristics with the (110) KNbO3 orientation indicate an initial peak in the coupling coefficient value (k2max = 8.8%) at a relatively low KNbO3 film thickness that appears attractive for fabricating devices with thinner films. The KNbO3 film with (001) orientation is found attractive for efficient acousto-optic (AO) device application with the formation of a symmetric waveguide structure (spinel(0.5 microm)/KNbO3(1.0 microm)/spinel). A high value of k2 = 23.5% with 50% diffraction efficiency has been obtained for the spinel(0.5 microm)/KNbO3(1.0 microm)/spinel structure at 1 GHz SAW frequency and 633 nm optical wavelength at a very low input drive power of 15.4 mW. PMID:12839169

  13. Repositioning of Cranial Bone Flaps Cut with a Diamond-Coated Threadwire Saw: 5-Year Experience with Cosmetic Cranioplasty without Fixation Devices.

    PubMed

    Shimizu, Satoru; Kondo, Koji; Yamazaki, Tomoya; Nakayama, Kenji; Yamamoto, Isao; Fujii, Kiyotaka

    2011-09-01

    Artificial fixation systems for cranial bone flaps have problems related to their materials and designs. We developed an alternative technique for supratentorial craniotomy that employs a diamond-coated threadwire saw (diamond T-saw), originally developed for spinal surgery, and reduces the bone gap for fitted bone flap fixation. The study subjects were 77 adults undergoing elective supratentorial craniotomy. After placing a burr hole at each corner of the craniotomy, we performed osteotomy between adjacent burr holes to approximately one-third of the length of the osteotomy with a craniotome; this leaves a bony bridge at each corner. The diamond T-saw was introduced between adjacent burr holes through the epidural space and a bridge was cut with reciprocating strokes. On closure, the bridge firmly supports the flap and only sutures are needed for fixation. Successful bone flap fixation was obtained in all followed-up cases. There were no technique-related complications such as dural laceration, flap displacement, or resorption. Our method is ideal for bone cuts in cosmetic cranioplasty; it is easy, safe, and inexpensive and avoids the need for flap fixation with artificial devices. PMID:22451833

  14. Recognition of organic solvents molecules by simultaneous detection using SAW oscillator sensors and optical fiber devices coated by Langmuir-Blodgett cadmium arachidate films.

    PubMed

    Penza, Michele; Cassano, Gennaro; Aversa, Patrizia; Antolini, Francesco; Cusano, Andrea; Cutolo, Antonello; Giordano, Michele; Nicolais, Luigi

    2006-08-01

    Surface acoustic waves (SAW) 433 and 315 MHz, two-port resonator-based oscillators coated with a Langmuir-Blodgett (LB) thin layer of chemosensitive cadmium arachidate (CdA) provide highly sensitive chemical acoustic sensors for detection and monitoring of organic vapors, at room temperature. LB CdA film-coated silica optical fibers (SOF) have been successfully fabricated and studied for organic solvents molecules sensing applications. The sensing performance of both types of acoustic and optical transducers has been compared for detecting six molecular species. Simultaneous measurements of frequency changes (delta f) and optoelectronic signal changes (deltaV) of the LB CdA film assembled onto SAW sensors and SOF devices have been realized for organic vapors recognition purposes. Six molecular species such as ethanol, methanol, isopropanol, ethylacetate, acetone, and toluene have been identified and recognized by a specific index (deltaf/deltaV), which can be considered a characteristic property of the chemosensitive material. The discrimination of the six molecular species examined also has been obtained by chemical patterns using a couple of specific index (deltaf433/deltaV; deltaf315/deltaV) measured by combining SAW 433 or 315 MHz oscillators and SOF sensing devices. Transient responses, calibration curves, intertransducer relationships, and chemical patterns are presented and discussed. PMID:16921902

  15. An Acoustic Charge Transport Imager for High Definition Television Applications: Low-Voltage SAW Amplifiers on Multilayer GaAs/ZnO Substrates

    NASA Technical Reports Server (NTRS)

    Hunt, W. D.; Brennan, K. F.; Summers, C. J.; Cameron, Thomas P.

    1996-01-01

    This thesis addresses the acoustoelectric issues concerning the amplification of surface acoustic waves (SAWs) and the reflection of SAWs from slanted reflector gratings on GaAs, with application to a novel acoustic charge transport (ACT) device architecture. First a simple model of the SAWAMP was developed, which was subsequently used to define the epitaxially grown material structure necessary to provide simultaneously high resistance and high electron mobility. In addition, a segmented SAWAMP structure was explored with line widths on the order of an acoustic wavelength. This resulted in the demonstration of SAWAMPS with an order of magnitude less voltage and power requirements than previously reported devices. A two-dimensional model was developed to explain the performance of devices with charge confinement layers less then 0.5 mm, which was experimentally verified. This model was extended to predict a greatly increased gain from the addition of a ZnO overlay. These overlays were experimentally attempted, but no working devices were reported due to process incompatibilities. In addition to the SAWAMP research, the reflection of SAWs from slanted gratings on GaAs was also studied and experimentally determined reflection coefficients for both 45 deg grooves and Al stripes on GaAs have been reported for the first time. The SAWAMp and reflector gratings were combined to investigate the integrated ring oscillator for application to the proposed ACT device and design parameters for this device have been provided.

  16. Eating with a saw for a jaw: functional morphology of the jaws and tooth-whorl in Helicoprion davisii.

    PubMed

    Ramsay, Jason B; Wilga, Cheryl D; Tapanila, Leif; Pruitt, Jesse; Pradel, Alan; Schlader, Robert; Didier, Dominique A

    2015-01-01

    The recent reexamination of a tooth-whorl fossil of Helicoprion containing intact jaws shows that the symphyseal tooth-whorl occupies the entire length of Meckel's cartilage. Here, we use the morphology of the jaws and tooth-whorl to reconstruct the jaw musculature and develop a biomechanical model of the feeding mechanism in these early Permian predators. The jaw muscles may have generated large bite-forces; however, the mechanics of the jaws and whorl suggest that Helicoprion was better equipped for feeding on soft-bodied prey. Hard shelled prey would tend to slip anteriorly from the closing jaws due to the curvature of the tooth-whorl, lack of cuspate teeth on the palatoquadrate (PQ), and resistance of the prey. When feeding on soft-bodied prey, deformation of the prey traps prey tissue between the two halves of the PQ and the whorl. The curvature of the tooth-whorl and position of the exposed teeth relative to the jaw joint results in multiple tooth functions from anterior to posterior tooth that aid in feeding on soft-bodied prey. Posterior teeth cut and push prey deeper into the oral cavity, while middle teeth pierce and cut, and anterior teeth hook and drag more of the prey into the mouth. Furthermore, the anterior-posterior edges of the teeth facilitate prey cutting with jaw closure and jaw depression. The paths traveled by each tooth during jaw depression are reminiscent of curved pathways used with slashing weaponry such as swords and knifes. Thus, the jaws and tooth-whorl may have formed a multifunctional tool for capturing, processing, and transporting prey by cyclic opening and closing of the lower jaw in a sawing fashion. PMID:25181366

  17. Electric field enhancement due to a saw-tooth asperity in a channel and implications on microscale gas breakdown

    NASA Astrophysics Data System (ADS)

    Venkattraman, Ayyaswamy

    2014-10-01

    The electric field enhancement due to an isolated saw-tooth asperity in an infinite channel is considered with the goal of providing some inputs to the choice of field enhancement factors used to describe microscale gas breakdown. The Schwarz-Christoffel transformation is used to map the interior of the channel to the upper half of the transformed plane. The expression for the electric field in the transformed plane is then used to determine the electric field distribution in the channel as well as field enhancement near the asperity. The effective field enhancement factor is determined and its dependence on operating and geometrical parameters is studied. While the effective field enhancement factor depends only weakly on the height of the asperity in comparison to the channel, it is influenced significantly by the base angles of the asperity. Due to the strong dependence of field emission current density on electric field, the effective field enhancement factor (βeff) is shown to vary rapidly with the applied electric field irrespective of the geometrical parameters. This variation is included in the analysis of microscale gas breakdown and compared with results obtained using a constant βeff as is done traditionally. Even though results for a varying βeff may be approximately reproduced using an equivalent constant βeff independent of E-field, it might be important for a range of operating conditions. This is confirmed by extracting βeff from experimental data for breakdown in argon microgaps with plane-parallel cathodes and comparing its dependence on the E-field. While the use of two-dimensional asperities is shown to be a minor disadvantage of the proposed approach in its current form, it can potentially help in developing predictive capabilities as opposed to treating βeff as a curve-fitting parameter.

  18. Prediction of Performance of Diamond Wire Saw with Respect to Texture Characteristics of Rock / Prognozowanie Wydajno?ci Pracy Strunowej Pi?y Diamentowej W Odniesieniu Do Charakterystyki Tekstury Ska?

    NASA Astrophysics Data System (ADS)

    Ghaysari, N.; Ataei, M.; Sereshki, F.; Mikaiel, R.

    2012-12-01

    In this study, prediction of production rate in diamond wire saw has been investigated. Performance measurements of diamond wire saw carried out in 7 different quarries of carbonate rocks in Iran. For determination textural properties, rock samples were collected from these quarries. At first, a thin section was prepared for each rock and then 5 digital photographs were taken from each section. After this, all images were digitized using AutoCAD software. Then, area, perimeter, longest diameter and shortest diameter were assigned. According to these parameters, all of the other textural characteristics and texture coefficient were determined too. The correlation between sawing rate and textural characteristics were evaluated using multiple and simple regression analyses. Then developed model was validated by P-value test. It was concluded that area, perimeter, diameter equivalent and index of grain size homogeneity are very effective on production rate. Production rate using diamond wire saw can reliably be predicted using developed model.

  19. Palaeolimnological evidence for an east-west climate see-saw in the Mediterranean since AD 900

    NASA Astrophysics Data System (ADS)

    Roberts, Neil; Moreno, Ana; Valero-Garcs, Blas L.; Corella, Juan Pablo; Jones, Matthew; Allcock, Samantha; Woodbridge, Jessie; Morelln, Mario; Luterbacher, Juerg; Xoplaki, Elena; Trke?, Murat

    2012-03-01

    During the period of instrumental records, the North Atlantic Oscillation (NAO) has strongly influenced inter-annual precipitation variations in the western Mediterranean, while some eastern parts of the basin have shown an anti-phase relationship in precipitation and atmospheric pressure. Here we explore how the NAO and other atmospheric circulation modes operated over the longer timescales of the Medieval Climate Anomaly (MCA) and Little Ice Age (LIA). High-resolution palaeolimnological evidence from opposite ends of the Mediterranean basin, supplemented by other palaeoclimate data, is used to track shifts in regional hydro-climatic conditions. Multiple geochemical, sedimentological, isotopic and palaeoecological proxies from Estanya and Montcorts lakes in northeast Spain and Nar lake in central Turkey have been cross-correlated at decadal time intervals since AD 900. These dryland lakes capture sensitively changes in precipitation/evaporation (P/E) balance by adjustments in water level and salinity, and are especially valuable for reconstructing variability over decadal-centennial timescales. Iberian lakes show lower water levels and higher salinities during the 11th to 13th centuries synchronous with the MCA and generally more humid conditions during the LIA' (15th-19th centuries). This pattern is also clearly evident in tree-ring records from Morocco and from marine cores in the western Mediterranean Sea. In the eastern Mediterranean, palaeoclimatic records from Turkey, Greece and the Levant show generally drier hydro-climatic conditions during the LIA and a wetter phase during the MCA. This implies that a bipolar climate see-saw has operated in the Mediterranean for the last 1100 years. However, while western Mediterranean aridity appears consistent with persistent positive NAO state during the MCA, the pattern is less clear in the eastern Mediterranean. Here the strongest evidence for higher winter season precipitation during the MCA comes from central Turkey in the northeastern sector of the Mediterranean basin. This in turn implies that the LIA/MCA hydro-climatic pattern in the Mediterranean was determined by a combination of different climate modes along with major physical geographical controls, and not by NAO forcing alone, or that the character of the NAO and its teleconnections have been non-stationary.

  20. Combination of e-beam lithography and of high velocity AIN/diamond-layered structure for SAW filters in X band.

    PubMed

    Kirsch, Philippe; Assouar, Mohamed B; Elmazria, Omar; Hakiki, M El; Mortet, Vincent; Alnot, Patrick

    2007-07-01

    In this work, we report on the fabrication results of surface acoustic wave (SAW) devices operating at frequencies up to 8 GHz. In previous work, we have shown that high acoustic velocities (9 to 12 km/s) are obtained from the layered AIN/diamond structure. The interdigital transducers (IDTs) made of aluminium with resolutions up to 250 nm were successfully patterned on AIN/diamond-layered structures with an adapted technological process. The uniformity and periodicity of IDTs were confirmed by field emission scanning electron microscopy and atomic force microscopy analyses. A highly oriented (002) piezoelectric aluminum nitride thin film was deposited on the nucleation side of the CVD diamond by magnetron sputtering technique. The X-ray diffraction effectuated on the AIN/diamond-layered structure exhibits high intensity peaks related to the (002) AIN and (111) diamond orientations. According to the calculated dispersion curves of velocity and the electromechanical coupling coefficient (K2), the AIN layer thickness was chosen in order to combine high velocity and high K2. Experimental data extracted from the fabricated SAW devices match with theoretical values quite well. PMID:17718340

  1. Evaluation and selection of LiNbO(3) and LiTaO(3) substrates for SAW devices by the LFB ultrasonic material characterization system.

    PubMed

    Kushibiki, J; Ohashi, Y; Ono, Y

    2000-01-01

    This paper demonstrates the evaluation and selection of commercially available LiNbO(3) and LiTaO(3) single crystals and wafers for surface acoustic wave (SAW) devices using the line-focus-beam ultrasonic material characterization (LFB-UMC) system. This system enables measuring leaky-SAW (LSAW) propagation characteristics precisely and efficiently for a number of specimens. The wafers are prepared from the top, middle, and bottom parts of four 128 degrees YX LiNbO(3) and seven X-112 degrees Y LiTaO(3) single crystals. For both series of crystals, the measured LSAW velocities increase from top to bottom in the crystals and with the increasing crystal growth number. The velocity changes for all wafers are 0.036% for 128 degrees YX LiNbO(3) and 0.035% for X-112 degrees Y LiTaO(3), corresponding to changes of 0.038 mol% and 0.075 mol% in Li(2)O concentration, respectively. Moreover, the inhomogeneity in the first X-112 degrees Y LiTaO(3) single crystal caused by some undesirable wafer fabrication processes can be detected precisely, although it is difficult for the conventional methods to obtain such information. PMID:18238642

  2. Binary Channel SAW Mustard Gas Sensor Based on PdPc0.3PANI0.7 hybrid Sensitive Film

    NASA Astrophysics Data System (ADS)

    Shi, Y. B.; Xiang, J. J.; Feng, Q. H.; Hu, Z. P.; Zhang, H. Q.; Guo, J. Y.

    2006-10-01

    This paper discussed the working principle of binary channel surface acoustic wave (SAW) lithium niobate piezoelectric chip detecting mustard, established the mathematic model of beat frequency output ?f and the mustard gas density ?. The MEMS craft solved the parameters of the binary channel SAW chip such as its interdigital electrode number was 15~25 couple, width and spacing were both 25m, degree of overlapping was 2mm, fundamental frequency was 10~35MHz, frequency-domain width was 5~20Hz, and its back pt hot film's. According to TG-DSC thermal analysis, vacuum coating craft was adopted to solve the hybrid sensitive film forming craft parameter of PdPc0.3PANI0.7(phthalocyanine palladium0.3Poiyaniline0.7). The micro-appearance of sensitive film was analyzed through SEM. The sensor's sensitivity and response characteristic were tested and analyzed: appear linear change, its response time is less than 5min while its recovery time is less than 8min.

  3. An evaluation of an aftermarket local exhaust ventilation device for suppressing respirable dust and respirable crystalline silica dust from powered saws.

    PubMed

    Garcia, Alberto; Jones, Erica; Echt, Alan S; Hall, Ronald M

    2014-01-01

    The objective of this study was to quantify the respirable dust and respirable silica exposures of roofing workers using an electric-powered circular saw with an aftermarket local exhaust ventilation attachment to cut concrete roofing tiles. The study was conducted to determine whether the local exhaust ventilation attachment was able to control respirable dust and respirable silica exposure below occupational exposure limits (OELs). Time-integrated filter samples and direct reading respirable dust concentrations were evaluated. The local exhaust ventilation consisted of a shroud attached to the cutting plane of the saw; the shroud was then connected to a small electric axial fan, which is intended to collect dust at the point of generation. All sampling was conducted with the control in use. Roofers are defined as those individuals who only lay tiles. Cutters/roofers are defined as those workers who operate the powered saw to cut tiles and also lay tiles. Respirable dust from this evaluation ranged from 0.13 to 6.59 milligrams per cubic meter (mg/m(3)) with a geometric mean of 0.38 mg/m(3) for roofers and from 0.45 to 3.82 mg/m(3) with a geometric mean of 1.84 mg/m(3) for cutters/roofers. Cutters/roofers usually handle areas close to crevices, edges, or tips of the roof whereas roofers handle areas where complete tiles can be placed. The respirable dust exposures for all cutters/roofers indicated concentrations exceeding the Occupational Safety and Health Administration's (OSHA) permissible exposure limit (PEL) for respirable dust containing silica; it was also exceeded for some of the roofers. The respirable silica concentrations ranged from 0.04 to 0.15 mg/m(3) with a geometric mean of 0.09 mg/m(3) for roofers, and from 0.13 to 1.21 mg/m(3) with a geometric mean of 0.48 mg/m(3) for cutters/roofers. As with respirable dust, the respirable silica exposures for cutters/roofers were higher than the exposures for roofers. PMID:25148513

  4. An Evaluation of an Aftermarket Local Exhaust Ventilation Device for Suppressing Respirable Dust and Respirable Crystalline Silica Dust from Powered Saws

    PubMed Central

    Garcia, Alberto; Jones, Erica; Echt, Alan S.; Hall, Ronald M.

    2015-01-01

    The objective of this study was to quantify the respirable dust and respirable silica exposures of roofing workers using an electric powered circular saw with an aftermarket local exhaust ventilation attachment to cut concrete roofing tiles. The study was conducted to determine whether the local exhaust ventilation attachment was able to control respirable dust and respirable silica exposure below occupational exposure limits. Time-integrated filter samples and direct reading respirable dust concentrations were evaluated. The local exhaust ventilation consisted of a shroud attached to the cutting plane of the saw; the shroud was then connected to a small electric axial fan, which is intended to collect dust at the point of generation. All sampling was conducted with the control in use. Roofers are defined as those individuals who solely lay tiles. Cutters/roofers are defined as those workers who operate the powered saw to cut tiles and also lay tiles. Respirable dust from this evaluation ranged from 0.13 to 6.59 milligrams per cubic meter (mg/m3) with a geometric mean of 0.38 mg/m3 for roofers and from 0.45 to 3.82 mg/m3 with a geometric mean of 1.84 mg/m3 for cutters/roofers. Cutters/roofers usually handle areas close to crevices, edges, or tips of the roof whereas roofers handle areas where complete tiles can be placed. The respirable dust exposures for all cutters/roofers indicated concentrations exceeding the Occupational Safety and Health Administrations (OSHA) permissible exposure limit (PEL) for respirable dust containing silica; it was also exceeded for some of the roofers. The respirable silica concentrations ranged from 0.04 to 0.15 mg/m3 with an average of 0.09 mg/m3 for roofers, and from 0.13 to 1.21 mg/m3 with an average of 0.48 mg/m3 for cutters/roofers. As with respirable dust, the respirable silica exposures to cutters/roofers were higher than the exposures for roofers. PMID:25148513

  5. Development of methods of producing large areas of silicon sheet by the slicing of silicon ingots using Inside Diameter (I.D.) saws

    NASA Technical Reports Server (NTRS)

    Aharonyan, P.

    1980-01-01

    Modifications to a 16 inch STC automated saw included: a programmable feed system; a crystal rotating system; and a STC dynatrack blade boring and control system. By controlling the plating operation and by grinding the cutting edge, 16 inch I.D. blades were produced with a cutting edge thickness of .22 mm. Crystal rotation mechanism was used to slice 100 mm diameter crystals with a 16 inch blade down to a thickness of .20 mm. Cutting rates with crystal rotation were generally slower than with standard plunge I.D. slicing techniques. Using programmed feeds and programmed rotation, maximum cutting rates were from 0.3 to 1.0 inches per minute.

  6. Development of methods of producing large areas of silicon sheet by the slicing of silicon ingots using Inside-Diameter (I.D.) saws

    NASA Technical Reports Server (NTRS)

    Aharonyan, P.

    1980-01-01

    Inside diametar wafering equipment, blades and processes were used to develop methods to produce large areas of silicon sheet. Modifications to a 16 inch STC automated saw included: programmable feed system, crystal rotating system, and STC dynatrack blade monitoring and control system. By controlling the plating operation and by grinding of the cutting edge, 16 inch ID blades with a cutting edge thickness of .22 mm can be produced. Crystal rotation mechanism was used to slice 100 mm diameter crystals with a 16 inch blade down to a thickness of .20 mm. Cutting rates with crystal rotation were generally slower than with standard plunge ID slicing techniques. Using programmed feeds and programmed rotation, maximum cutting rates were from 0.3 to 1.0 inches per minute.

  7. Precision distance measurement using a two-photon absorption process in a silicon avalanche photodiode with saw-tooth phase modulation.

    PubMed

    Tanaka, Yosuke; Tominaka, Seiji; Kurokawa, Takashi

    2015-10-01

    We present a novel configuration of a precision laser distance measurement based on the two-photon absorption (TPA) photocurrent from a silicon avalanche photodiode (Si-APD). The proposed system uses saw-tooth phase modulation, known as serrodyne modulation, in order to shift the frequency of the reference light from that of the probe light. It suppresses the coherent interference noise between the probe and the reference. The serrodyne modulation also enables lock-in detection of the TPA photocurrent. Furthermore, it contributes to the reduction of the system components. The precision measurement is experimentally demonstrated by measuring a fiber length difference of 2.6 m with a standard deviation of 27 ?m under constant temperature. The high-precision displacement measurement is also demonstrated by measuring the temperature-induced change in the optical path length difference of a fiber interferometer. PMID:26479662

  8. Using Nano-mechanics and Surface Acoustic Wave (SAW) for Disease Monitoring and Diagnostics at a Cellular Level in Red Blood Cells

    NASA Astrophysics Data System (ADS)

    Sivanantha, Ninnuja; Ma, Charles; Collins, David J.; Sesen, Muhsincan; Brenker, Jason; Coppel, Ross L.; Neild, Adrian; Alan, Tuncay

    A popular approach to monitoring diseases and their diagnosis is through biological, pathological or immunological characterization. However, at a cellular level progression of certain diseases manifests itself through mechanical effects as well. Here, we present a method which exploits localised flow; surface acoustic wave (SAW) induced acoustic streaming in a 9 μL droplet to characterize the adhesive properties of red blood cells (healthy, gluteraldehyde treated and malaria infected) in approximately 50 seconds. Our results show a 79% difference in cell mobilization between healthy malaria infected RBCs (and a 39% difference between healthy and treated ones), indicating that the method can serve as a platform for rapid clinical diagnosis; where separation of two or more different cell populations in a mixed solution is desirable. It can also act as a key biomarker for monitoring some diseases offering quantitative measures of disease progression and response to therapy.

  9. Use of Classical Least Squares/Partial Least Squares (CLS/PLS) hybrid algorithm for calibration and calibration maintenance of Surface Acoustic Wave (SAW) devices.

    SciTech Connect

    Simonson, Robert Joseph; Rivera, Dion Arledge; Staton, Alan W.; Alam, Mary Kathleen; Yelton, William Graham

    2003-06-01

    Many data analysis algorithms that are currently employed in SAW sensors lack the ability to easily maintain calibration models in the presence of unmodeled interferents or sensor drift. The classical least squares/partial least squares (CLS/PLS) hybrid algorithm is tested in this study for its ability to update calibration models for unmodeled interferents and sensor drift with information from only a single recalibration standard. Use of the CLS/PLS hybrid algorithm for calibration and calibration maintenance of surface acoustic wave (SAW) devices was investigated for synthetic mixtures of iso-octane-methanol-water and with synthetic mixtures of nerve agent analogs, di-iso-propyl methyl phosphonate (DIMP)-kerosene-water along with a true ternary mixture of dimethyl methyl phosphonate (DMMP)-kerosene-water. Calibration statistics using the hybrid algorithm were found to be as good as those obtained from a standard partial least squares (PLS) analysis. In prediction, the hybrid algorithm models were found to perform equivalently to PLS models in the absence of unmodeled interferents or sensor drift, with an accuracy of 5-10% of the reference values and a high degree of precision. In the case of prediction in the presence of unmodeled interferents and/or sensor drift, PLS models and prediction augmented CLS/PLS (PACLS/PLS) hybrid models were compared using a single standard sample to update each model for prediction. For the cases studied, PACLS/PLS hybrid models were comparable to or outperformed updated PLS models that used subset recalibration or piece-wise direct standardization.

  10. The visual response properties of neurons in the nucleus of the basal optic root of the northern saw-whet owl (Aegolius acadicus).

    PubMed

    Wylie, D R; Shaver, S W; Frost, B J

    1994-01-01

    The nucleus of the basal optic root (nBOR) in birds is a component of the accessory optic system (AOS) which is involved in the analysis of visual flowfields normally resulting from self-motion. Using standard extracellular techniques, we recorded from 81 single-unit and multi-unit clusters in the nBOR of the northern saw-whet owl, Aegolius acadicus, an avian species that has a visual system with frontal emphasis. These cells responded best to large patterns of random dots moving either upward (52%), downward (31%) or nasal to temporal (N-T; contralateral visual field; 15%). Only 2 units (2%) preferred temporal to nasal motion. 'Up' units were found in the dorsal portion of the nucleus whereas 'Down' units were located more ventrally. The N-T units were found in both the lateral margin of the nucleus and ventral to the Down units in the lateral half of the nucleus. About half of the units tested (10/19) responded to stimulation of the ipsilateral as well as the contralateral eye. For all but one cell, the direction preference of both eyes was the same in visual space. When compared with previous studies of pigeons (Columba livia) and chickens (Gallus domesticus), these findings reveal that the nBOR in all three avian species have important similarities with respect to direction preference and functional compartmentalization. Furthermore, the high proportion of binocular neurons found in the nBOR of the saw-whet owl is similar to the condition generally reported in frontal eyed mammals and hence may reflect adaptation. PMID:8306188

  11. Investigations of AlN thin film crystalline properties in a wide temperature range by in situ X-ray diffraction measurements: Correlation with AlN/sapphire-based SAW structure performance.

    PubMed

    At Assa, Keltouma; Elmazria, Omar; Boulet, Pascal; Aubert, Thierry; Legrani, Ouadra; Mangin, Denis

    2015-07-01

    Aluminum nitride on sapphire is a promising substrate for SAW sensors operating at high temperatures and high frequencies. To get a measure of the suitability and temperature stability of such devices, an experimental relationship between the SAW performance and the structural properties of the AlN thin films was investigated in the temperature range between the ambient temperature and 1000C. The crystalline structure of the AlN films was examined in situ versus temperature by X-ray diffraction. The results reveal that the AlN films remain (002) oriented even at high temperatures. A gradual increase of the tensile stress in the film due to the thermal expansion mismatch with the substrate has been observed. This increase accelerates around 600C as the AlN film crystalline quality improves. This phenomenon could explain the amelioration in the SAW performance of AlN/sapphire devices observed previously between 600C and 850C. At higher temperatures, surface oxidation of the AlN films reduces the SAW performance. The potential of ZnO thin films as protective layers was finally examined. PMID:26168184

  12. Determination of Campesterol, Stigmasterol, and Beta-Sitosterol in Saw Palmetto Raw Materials and Dietary Supplements by Gas Chromatography: Collaborative Study

    PubMed Central

    Sorenson, Wendy R.; Sullivan, Darryl

    2008-01-01

    An interlaboratory study was conducted to evaluate a method for the determination of campesterol, stigmasterol, and beta-sitosterol in saw palmetto raw materials and dietary supplements at levels >1.00 mg/100 g based on a 2?3 g sample. Test samples were saponified at high temperature with ethanolic KOH solution. The unsaponifiable fraction containing phytosterols (campesterol, stigmasterol, and beta-sitosterol) was extracted with toluene. Phytosterols were derivatized to trimethylsilyl ethers and then quantified by gas chromatography with hydrogen flame ionization detection. Twelve blind duplicates, one of which was fortified, were successfully analyzed by 10 collaborators. Recoveries were obtained for the sample that was fortified. The results were 99.8, 111, and 111% for campesterol, stigmasterol, and beta-sitosterol, respectively. For repeatability, the relative standard deviation (RSDr) ranged from 3.93 to 17.3% for campesterol, 3.56 to 22.7% for stigmasterol, and 3.70 to 43.9% for beta-sitosterol. For reproducibility, the RSDR ranged from 7.97 to 22.6%, 0 to 26.7%, and 5.27 to 43.9% for campesterol, stigmasterol, and beta-sitosterol, respectively. Overall, the Study Director approved 5 materials with acceptable HorRat values for campesterol, stigmasterol, and beta-sitosterol ranging from 1.02 to 2.16. PMID:17580618

  13. The Different Sensitive Behaviors of a Hydrogen-Bond Acidic Polymer-Coated SAW Sensor for Chemical Warfare Agents and Their Simulants

    PubMed Central

    Long, Yin; Wang, Yang; Du, Xiaosong; Cheng, Luhua; Wu, Penglin; Jiang, Yadong

    2015-01-01

    A linear hydrogen-bond acidic (HBA) linear functionalized polymer (PLF), was deposited onto a bare surface acoustic wave (SAW) device to fabricate a chemical sensor. Real-time responses of the sensor to a series of compounds including sarin (GB), dimethyl methylphosphonate (DMMP), mustard gas (HD), chloroethyl ethyl sulphide (2-CEES), 1,5-dichloropentane (DCP) and some organic solvents were studied. The results show that the sensor is highly sensitive to GB and DMMP, and has low sensitivity to HD and DCP, as expected. However, the sensor possesses an unexpected high sensitivity toward 2-CEES. This good sensing performance can’t be solely or mainly attributed to the dipole-dipole interaction since the sensor is not sensitive to some high polarity solvents. We believe the lone pair electrons around the sulphur atom of 2-CEES provide an electron-rich site, which facilitates the formation of hydrogen bonding between PLF and 2-CEES. On the contrary, the electron cloud on the sulphur atom of the HD molecule is offset or depleted by its two neighbouring strong electron-withdrawing groups, hence, hydrogen bonding can hardly be formed. PMID:26225975

  14. A wideband multi-mode SAW filter employing pitch-modulated IDTs on Cu-grating/15 degrees YX-LiNbO3-substrate structure.

    PubMed

    Hashimoto, Ken-ya; Miyamoto, Takashi; Shimada, Ken-ta; Omori, Tatsuya; Yamaguchi, Masatsune

    2010-05-01

    This paper describes an attempt to develop extremely wideband multi-mode surface acoustic wave (MMS) filters in the gigahertz range. The Cu-grating/15 degrees YX-LiNbO3 (15-LN)-substrate structure is employed. First, a design tool developed for the present purpose is detailed. Precise simulation is performed using a modified coupling-of-modes model, in which the coupling between propagating surface and bulk acoustic waves is taken into account. Parameters necessary for the simulation are determined experimentally. Next, this simulation tool is used to design a wideband MMS filter employing pitch-modulated IDTs proposed by the authors. It is shown that a fractional bandwidth of more than 12% is achievable by successfully using six SAW resonances supported in the MMS structure. The designed MMS filter was fabricated on a Cu-grating/15-LN-substrate structure. The passband width of 12.6% and the minimum insertion loss of 1.2 dB were experimentally obtained around 850 MHz. The measured result was in good agreement with the simulation. PMID:20442030

  15. Effects of different levels of wheat bran, rice bran and maize powder supplementation with saw dust on the production of shiitake mushroom (Lentinus edodes (Berk.) Singer).

    PubMed

    Moonmoon, Mahbuba; Shelly, Nasrat Jahan; Khan, Md Asaduzzaman; Uddin, Md Nazim; Hossain, Kamal; Tania, Mousumi; Ahmed, Saleh

    2011-10-01

    The cultivation of shiitake mushroom (Lentinus edodes) is increasing rapidly in Bangladesh due to its nutritional and medicinal importance with excellent flavor and longer shelf life. With the aim of increased production, we have cultivated L. edodes on saw dust (SD) supplemented with different levels (10%, 15%, 20%, 25%, 30%, 35% and 40%) of wheat bran (WB), rice bran (RB), maize powder (MP) and their combination (WB+RB+MP=1:1:1) to investigate the growth, yield and quality of this mushroom. Most of the growth, yield and quality parameters varied significantly when mushrooms were cultivated with different levels of supplementation. The yield of mushroom was increased with the level of each supplementation upto a certain level, and then decreased. SD supplemented with 25% WB produced the highest number of fruiting bodies (34.8/500g packet), highest biological yield (153.3/500g packet), and biological efficiency (76.6%) of L. edodes. But the yield of the best quality mushroom was observed on SD with 40% WB supplementation; however, the qualities were not always supplementation dose dependent. In this study, we report that 25% WB supplementation with SD may be very effective for higher yield and 40% WB supplementation for better quality of L. edodes. PMID:23961143

  16. Effects of different levels of wheat bran, rice bran and maize powder supplementation with saw dust on the production of shiitake mushroom (Lentinus edodes (Berk.) Singer)

    PubMed Central

    Moonmoon, Mahbuba; Shelly, Nasrat Jahan; Khan, Md. Asaduzzaman; Uddin, Md. Nazim; Hossain, Kamal; Tania, Mousumi; Ahmed, Saleh

    2010-01-01

    The cultivation of shiitake mushroom (Lentinus edodes) is increasing rapidly in Bangladesh due to its nutritional and medicinal importance with excellent flavor and longer shelf life. With the aim of increased production, we have cultivated L. edodes on saw dust (SD) supplemented with different levels (10%, 15%, 20%, 25%, 30%, 35% and 40%) of wheat bran (WB), rice bran (RB), maize powder (MP) and their combination (WB+RB+MP=1:1:1) to investigate the growth, yield and quality of this mushroom. Most of the growth, yield and quality parameters varied significantly when mushrooms were cultivated with different levels of supplementation. The yield of mushroom was increased with the level of each supplementation upto a certain level, and then decreased. SD supplemented with 25% WB produced the highest number of fruiting bodies (34.8/500g packet), highest biological yield (153.3/500g packet), and biological efficiency (76.6%) of L. edodes. But the yield of the best quality mushroom was observed on SD with 40% WB supplementation; however, the qualities were not always supplementation dose dependent. In this study, we report that 25% WB supplementation with SD may be very effective for higher yield and 40% WB supplementation for better quality of L. edodes. PMID:23961143

  17. The Different Sensitive Behaviors of a Hydrogen-Bond Acidic Polymer-Coated SAW Sensor for Chemical Warfare Agents and Their Simulants.

    PubMed

    Long, Yin; Wang, Yang; Du, Xiaosong; Cheng, Luhua; Wu, Penglin; Jiang, Yadong

    2015-01-01

    A linear hydrogen-bond acidic (HBA) linear functionalized polymer (PLF), was deposited onto a bare surface acoustic wave (SAW) device to fabricate a chemical sensor. Real-time responses of the sensor to a series of compounds including sarin (GB), dimethyl methylphosphonate (DMMP), mustard gas (HD), chloroethyl ethyl sulphide (2-CEES), 1,5-dichloropentane (DCP) and some organic solvents were studied. The results show that the sensor is highly sensitive to GB and DMMP, and has low sensitivity to HD and DCP, as expected. However, the sensor possesses an unexpected high sensitivity toward 2-CEES. This good sensing performance can't be solely or mainly attributed to the dipole-dipole interaction since the sensor is not sensitive to some high polarity solvents. We believe the lone pair electrons around the sulphur atom of 2-CEES provide an electron-rich site, which facilitates the formation of hydrogen bonding between PLF and 2-CEES. On the contrary, the electron cloud on the sulphur atom of the HD molecule is offset or depleted by its two neighbouring strong electron-withdrawing groups, hence, hydrogen bonding can hardly be formed. PMID:26225975

  18. The effect of a SiO2 layer on the performance of a ZnO-based SAW device for high sensitivity biosensor applications

    NASA Astrophysics Data System (ADS)

    Chen, Xi; Liu, Dali; Chen, Jiansheng; Wang, Guolei

    2009-11-01

    The properties of ZnO/SiO2/Si surface acoustic wave (SAW) love mode biosensors are studied in this paper. This specific structure is very suitable for biosensors since the reactive ZnO surface offers the opportunity for effective bio-ZnO interfaces, and the development of sensors directly on Si substrates provides the chance for full integration with read-out and signal processing circuitry in the mature Si technology. However, investigations of the dependence of buffer layer SiO2 on the performance of biosensors are very few. Therefore, the main interest of this paper is to find the relation between the properties of biosensors and the SiO2 layer. Some important results are obtained by solving the coupled electromechanical field equations. It is found that the mass loading sensitivity can be further improved by adding the SiO2 layer; furthermore, the maximal sensitivity of the biosensors can be obtained by adjusting the thicknesses of the two layers. Accordingly, consideration of the buffer layer is very important in the optimization of devices. On the other hand, it is found that the thickness of the piezoelectric guiding layer has an evident effect on the electromechanical coupling coefficient, while that of the SiO2 layer has a tiny effect on it. Moreover, we find that the effect of initial stresses on the properties of biosensors depends on the distribution of acoustic flow power in the two layers. This analysis is meaningful for the manufacture and applications of the ZnO/SiO2/Si structure love wave biosensor.

  19. Thermal development of Cephalonomia tarsalis (Hymenoptera: Bethylidae) parasitoid of the saw-toothed stored product beetles of the genus Oryzaephilus sp. (Coleoptera: Sylvanidae).

    PubMed

    Eliopoulos, Panagiotis A; Kontodimas, Dimitrios C

    2016-02-01

    The effect of temperature on the development and survival of Cephalonomia tarsalis (Ashmead) (Hymenoptera: Bethylidae), larval ectoparasitoid of beetles of Oryzaephilus sp. (Coleoptera: Silvanidae) was studied in the laboratory. Durations of the development of the egg, larva and pupa were measured in eight constant temperatures (15, 17.5, 20, 25, 30, 32.5, 35 and 37.5°C) parasitizing larvae of the saw-toothed beetle Oryzaephilus surinamensis (L.) (Coleoptera: Silvanidae). The duration of development was decreased with temperature increase within the range 17.5-32.5°C. Survival was higher when immatures were exposed to medium temperatures (20-30°C) compared with those lived in a more extreme temperature regime (<20 and >30°C). Wasps failed to complete their development at 15 and 37.5°C. Thermal parameters (upper, lower and optimum developmental threshold, thermal constant) were estimated by fitting the linear and a non-linear (Logan I) model to our data. Upper and lower developmental thresholds ranged between 35.1-37.0°C and 13.2-13.8°C, respectively. The optimum temperature for development was estimated between 33.6°C and 34.6°C. Tests for developmental rate isomorphy (DRI) showed that change in the average proportion of time spent in each developmental stage was marginally significant, proving that development of C. tarsalis is probably incompatible with DRI. However, this conclusion is questionable given that lower developmental thresholds did not differ significantly among various developmental stages (bootstrap test). Thermal constant for total development was calculated 212.4 degree-days. Our results are discussed not only on the basis of thermal biology, but also of improving the efficiency of C. tarsalis as biocontrol agent. PMID:26857981

  20. Understanding processing-microstructure-properties relationships in Bi2Sr2CaCu2Ox/Ag round wires and enhanced transport through saw-tooth processing

    NASA Astrophysics Data System (ADS)

    Naderi, Golsa; Liu, Xiaotao; Nachtrab, William; Schwartz, Justin

    2013-10-01

    Superconducting magnets generating magnetic fields above 25 T are needed for many scientific applications. Due to fundamental limitations in NbTi and Nb3Sn, such high-field superconducting magnets require alternative high-field conductors. One candidate conductor is round wire composites of Bi2Sr2CaCu2Ox sheathed in a Ag-alloy matrix (Bi2212/Ag). The performance of such wires is sensitive to the heat treatment, so improvements in the critical current density (Jc) require a thorough understanding of the processing-structure-properties relationships. Here we present a two-part study. In part I, a new heat treatment approach, saw-tooth processing (STP), is introduced based upon previous results showing that Bi2212 nucleation is site-saturation limited. The microstructural evolution of Bi2212 filaments during processing is discussed and results from STP are compared with those from other processes. STP is shown to increase Jc by 120% and 70% relative to partial-melt processing at 5 T and self-field respectively, and by 65% and 34% relative to split-melt processing. Yet STP also complicates the heat treatment by introducing a number of new heat treatment variables that affect the grain morphology, phase assemblage and oxygen content of the Bi2212 filaments and thus the transport properties. In part II, the effects of STP heat treatment parameters on the microstructure and transport properties are discussed. It is shown that wires with the highest transport critical current densities primarily have filaments with two types of microstructures, one comprised primarily of highly textured Bi2212 grains, and another with a noticeable amount of Bi2Sr2CuOx with the Bi2212.

  1. Gilgamesh: He Who Saw All.

    ERIC Educational Resources Information Center

    California Univ., Berkeley. Office of Resources for International and Area Studies.

    The historical Gilgamesh was a Sumarian king of Uruk around 2700 B.C. Sumarian fragments of the legend that grew up around him have been found dating back to about 2000 B.C. These lesson plans on Gilgamesh were developed during the Office of Resources for International and Area Studies (ORIAS) summer institute on history through literature, in

  2. I ``Saw'' Newton's Three Laws

    NASA Astrophysics Data System (ADS)

    Shaw, Mike

    2012-11-01

    Would you like to build an inexpensive, highly visible, quickly assembled device that dramatically illustrates Newton's three laws of motion? This model incorporates sturdiness, high-profile visibility, and a student interest component that is sure to capture and hold their attention.

  3. Galileo SAW Jupiter's Rings, Too

    NASA Astrophysics Data System (ADS)

    Daubar, I. J.; Ockert-Bell, M. E.; Burns, J. A.; Veverka, J. F.; Thomas, P.; Belton, M.; Klaasen, K.; Galileo Imaging Team

    1997-07-01

    Because of better spatial resolution, different phase coverage, and superior signal-to-noise, Galileo's thirteen clear images of Jupiter's ring system taken during a single pass through the planet's shadow improve substantially upon Voyager data. In addition two Adrastea images fortuitously included the rings at phase angles around 83(deg) . By assuming a circular and equatorial main ring, and using the position of a star found in one ansa image, we fix the main ring's outer radius at 128940+/-50 km, slightly less than Voyager's value of 129130+/-100 km, and very close to Adrastea's orbit (128980 km). The ring's halo rises gradually starting near the 3:2 vertical Lorentz resonance at 122733 km. The gossamer ring, discovered in a single Voyager image, is clearly visible out to the frame's edge at 2.3 RJ. The main ring exhibits a marked drop in brightness at 127849+/-50 km, lying almost atop Metis's orbit at 127978 km. The ansa images also show apparent azimuthal structure: longitudinally alternating bright and dim patches. As previously noted in Voyager images, the brightnesses of the near and far arms differ by 10% or more. In contrast to Voyager, Galileo images show the near arm to be brighter. Galileo's shallow viewing angle (0.5(deg) above the ring plane) through the diaphanous ring may play a role in brightness variations. Results will also be presented describing the morphologies of the halo and gossamer ring, as well as phase functions for the ring's components.

  4. Equivalent networks for SAW gratings.

    PubMed

    Koshiba, M; Mitobe, S

    1988-01-01

    An equivalent-network approach is described for the analysis of surface-acoustic-wave gratings. Circuit parameters can be theoretically determined by applying the finite-element method to an infinite array. In this approach, all of the effects of piezoelectric perturbation, mechanical perturbation, and energy storage are taken into account. To show the validity and usefulness of this approach, examples are computed for groove and metallic gratings. Both short and open circuited metallic gratings are treated. For grooves on isotropic and Y-Z LiNbO(3) substrates, the dependence of reflection characteristics on groove depth is investigated. For aluminum strips on X-112 degrees Y LiTaO(3) 34 degrees Y-X quartz, Y-Z LiNbO(3), and 128 degrees Y -X LiNbO(3) substrates, the dependence on metallization ratio is investigated in detail. PMID:18290184

  5. SAWFAST - a SAW diffraction channelizer

    SciTech Connect

    Elliott, J.H.; Stokes, R.B.; Yen, K.H.

    1986-09-01

    One important aspect of modern electronic warfare systems is the ability to sort signals according to their frequency. This paper describes a novel surface acoustic wave channelizer to perform this sorting at IF frequencies. The operating principles are analogous to an optical diffraction grating. Prototype devices that cover a 260 MHz bandwidth with a sidelobe rejection to about 40 dB are described.

  6. Germany as We Saw It.

    ERIC Educational Resources Information Center

    Stanford Univ., CA.

    Close-up studies of German life in the Stuttgart area are reported by participants of Stanford University's 1961 National Defense Education Act second-level institute for secondary school teachers of German, held at Bad Boll, Germany. Topics covered include: (1) religious life, (2) political life, (3) problems of settlement, (4) occupational…

  7. Clay Swelling and Particle Redistribution in a Saw-Cut Fracture in the Paintbrush Nonwelded Unit of the Topopah Spring Tuff

    NASA Astrophysics Data System (ADS)

    Kneafsey, T. J.; Oldenburg, C. M.; Salve, R.

    2001-12-01

    Flow through the altered nonwelded tuffs of the Paintbrush unit (PTn) at Yucca Mountain, Nevada, is thought to be primarily through the highly porous rock matrix. Due to matrix flow and the sloping structure of the unit, the PTn is thought to divert downward-flowing water laterally. However, large fractures and faults in the PTn may also provide pathways for flow through the unit and these may prevent or interrupt lateral flow through the unit. In field tests where water was released directly into a fault in the altered PTn, flow rates declined over time. To evaluate processes such as matrix swelling and particle redistribution that might explain this decline, we performed a laboratory experiment using a 12 cm diameter x 21.6 cm long core with an axial saw-cut fracture. The core was extracted from the argillic Tpbt2C layer. We monitored permeability, inlet and outlet flow rate, and the volume change of the rock core (contained in a pressure vessel) while flow occurred through the fracture and matrix. Water containing various sodium chloride concentrations (1 M, 0.5 M, 0 M, and 1M) was flowed through the fracture to observe the effect of salt concentration on fracture permeability in the smectite-rich rock core. The sample swelled initially, despite the high salt concentration (1 M) of the inlet water. The permeability of the fracture decreased with declining salt concentration and increased with increasing salt concentration indicating that clay swelling decreased fracture aperture and reduced the flow rate. Particle redistribution (dispersion and flocculation) was indicated by particles in the effluent. Particles from lower salinity flows remained suspended in the effluent container, while those from higher salinity flows settled more easily, were larger, and more compact. If particle redistribution were controlling the flow, the permeability should have increased during low salinity water flow because of particle erosion. This work was supported by the Director, Office of Civilian Radioactive Waste Management, U.S. Department of Energy, through Memorandum Purchase Order EA9013MC5X between Bechtel SAIC Company, LLC and the Ernest Orlando Lawrence Berkeley National Laboratory (Berkeley Lab). The support is provided to Berkeley Lab through the U.S. Department of Energy Contract No. DE-AC03-76SF00098.

  8. Adaptive deconvolution using a SAW storage correlator

    NASA Astrophysics Data System (ADS)

    Bowers, J. E.; Kino, G. S.; Behar, D.; Olaisen, H.

    1981-05-01

    A new analog adaptive filter for deconvolving distorted signals is described. The filter uses a storage correlator which implements a clipped version of the least mean squared algorithm and uses a special iterative technique to achieve fast convergence. The new filter has a potential bandwidth of 100 MHz and would eventually handle pulsed signals of 10-microsecond width. For signals with time-bandwidth products of less than 100, the adaptation time is less than 1 ms, which allows operation in real time for most applications, including resolution of radar signals in a cluttered environment, removal of echoes from television signals, deconvolution of distorted signals in nondestructive evaluation, and also in telephony. The filter is particularly suited for radar and communications, as it processes signals directly in the VHF range. Two experiments related to ghost suppression of a pulse and to the field of NDE are described in this paper. The results are in good agreement with computer simulations and show a ghost suppression of 15 dB for the first example and a sidelobe suppression of 8 dB for a transducer signal. The adaptation time is less than 450 microseconds.

  9. Sensors based on SAW and FBAR technologies

    NASA Astrophysics Data System (ADS)

    Garca-Gancedo, L.; Milne, W. I.; Luo, J. K.; Flewitt, A. J.

    2013-08-01

    Over the last few years a number of sensing platforms are being investigated for their use in drug development, microanalysis or medical diagnosis. Lab-on-a-chip (LOC) are devices integrating more than one laboratory functions on a single device chip of a very small size, and typically consist of two main components: microfluidic handling systems and sensors. The physical mechanisms that are generally used for microfluidics and sensors are different, hence making the integration of these components difficult and costly. In this work we present a lab-on-a-chip system based on surface acoustic waves (for fluid manipulation) and film bulk acoustic resonators (for sensing). Coupling surface acoustic waves into liquids induces acoustic streaming and motion of micro-droplets, whilst it is well-known that bulk acoustic waves can be used to fabricate microgravimetric sensors. Both technologies offer exceptional sensitivity and can be fabricated from piezoelectric thin films deposited on Si substrates, reducing the fabrication time/cost of the LOC devices.

  10. What Brown saw and you can too

    NASA Astrophysics Data System (ADS)

    Pearle, Philip; Collett, Brian; Bart, Kenneth; Bilderback, David; Newman, Dara; Samuels, Scott

    2010-12-01

    A discussion of Robert Brown's original observations of particles ejected by pollen of the plant Clarkia pulchella undergoing what is now called Brownian motion is given. We consider the nature of those particles and how he misinterpreted the Airy disk of the smallest particles to be universal organic building blocks. Relevant qualitative and quantitative investigations with a modern microscope and with a "homemade" single lens microscope similar to Brown's are presented.

  11. Analysis of aging data on SAW oscillators

    NASA Technical Reports Server (NTRS)

    Parker, T. E.

    1980-01-01

    Test oscillators including delay lines and resonators in the 300-400 MHz range have been investigated with reference to the long-term stability (aging) characteristics. All devices were fabricated on rotated Y-cut quartz plates (40 deg), and either gold or platinum metallization was used; all packages were high-quality hermetic enclosures, and the mounting was strictly mechanical, with no organics or silicone rubbers used. It is shown that drift of less than 2 ppm in the first year can be obtained on a significant fraction of the devices when reasonably clean packages are used. The data also suggest that the transducer metallization (at least for aluminum) is very likely the source of the relaxation mechanism that causes the frequency drift.

  12. Wireless SAW Sensors Having Integrated Antennas

    NASA Technical Reports Server (NTRS)

    Gallagher, Mark (Inventor); Malocha, Donald C. (Inventor)

    2015-01-01

    A wireless surface acoustic wave sensor includes a piezoelectric substrate, a surface acoustic wave device formed on the substrate, and an antenna formed on the substrate. In some embodiments, the antenna is formed on the surface of the substrate using one or more of photolithography, thin film processing, thick film processing, plating, and printing.

  13. Effects of D-004, a lipid extract of the fruit of the Cuban royal palm (Roystonea regia) or the lipidosterolic extract of saw palmetto (Serenoa repens) on the sexual activity in male rats: A controlled, experimental study

    PubMed Central

    Fernndez, Lilia C.; Mas, Rosa; Fernndez, Julio; Mendoza, Sarah; Gmez, Rafael; Pardo, Balia

    2008-01-01

    Background: The etiology of benign prostatic hyperplasia (BPH) is not completely understood, but hormonal changes in aging men seem to be pivotal. Dihydrotestosterone, a potent, active metabolite of testosterone, is formed by the enzymatic action of prostate 5?-reductase and causes cell growth and hyperplasia. Consistent with this action, male sexual dysfunction has been clinically documented to be among the drug-related adverse events associated with 5?-reductase inhibitors. The lipidosterolic extract of saw palmetto (LESP) fruit (Serenoa repens) has been used to treat BPH. D-004, a lipid extract of Roystonea regia Royal palm fruit, has been found to prevent prostatic hyperplasia induced by testoste-rone in rodents and to competitively inhibit prostate 5?-reductase activity in vitro. Objective: The purpose of this study was to assess the effects of D-004 and LESP, administered as single or repeated doses, on the sexual activity in male rats. Methods: This controlled, experimental study was conducted at the Pharmacology Department, Centre of Natural Products, National Centre for Scientific Research, Havana City, Cuba. Adult male Wistar rats weighing 250 to 300 g were randomized into 5 groups: 2 groups treated orally with D-004 (400 and 800 mg/kg); 2 groups treated orally with LESP (400 and 800 mg/kg); and 1 control group orally administered a water vehicle. Sexual activity behavior (the number of mounts and intromissions, mount latency, and intromission latency) was assessed during 2 observation periods: 90 minutes after the initial dose and at the end of the 30-day treatment. Latency was defined as time elapsed between the first mount and intromission. Results: A total of 50 rats (mean [SD] age, 10 [3] weeks; mean [SD] weight, 295 [10] g) were included in the experiment. There were no significant difterences in the mean number of mounts, intromissions, mount latency, or intromission latency in the groups treated with single or repeated doses of D-004 or LESP (400 and 800 mg/kg) compared with the controls. There was also no between-group difterence in mating behavior among the active treatment groups. All rats survived up to study completion, with normal behavior (weight gain, food intake, daily observations, without any sign of toxicity). There were no observable adverse events during the study. Conclusions: D-004 and LESP administered as a single dose or repeated doses for 30 days did not significantly affect male rat sexual activity behavior compared with a vehicle control group. PMID:24692784

  14. Weighted SAW reflector gratings for orthogonal frequency coded SAW tags and sensors

    NASA Technical Reports Server (NTRS)

    Puccio, Derek (Inventor); Malocha, Donald (Inventor)

    2011-01-01

    Weighted surface acoustic wave reflector gratings for coding identification tags and sensors to enable unique sensor operation and identification for a multi-sensor environment. In an embodiment, the weighted reflectors are variable while in another embodiment the reflector gratings are apodized. The weighting technique allows the designer to decrease reflectively and allows for more chips to be implemented in a device and, consequently, more coding diversity. As a result, more tags and sensors can be implemented using a given bandwidth when compared with uniform reflectors. Use of weighted reflector gratings with OFC makes various phase shifting schemes possible, such as in-phase and quadrature implementations of coded waveforms resulting in reduced device size and increased coding.

  15. I Can't Believe I Saw the Whole Thing!

    ERIC Educational Resources Information Center

    Asimov, Isaac

    1972-01-01

    The author explains some of the principles underlying holography, a process by which literally hundreds of images can be stored on a single piece of film and then reproduced, one by one, in three dimension.'' (Editor/AK)

  16. Surface photovoltage measurements and finite element modeling of SAW devices.

    SciTech Connect

    Donnelly, Christine

    2012-03-01

    Over the course of a Summer 2011 internship with the MEMS department of Sandia National Laboratories, work was completed on two major projects. The first and main project of the summer involved taking surface photovoltage measurements for silicon samples, and using these measurements to determine surface recombination velocities and minority carrier diffusion lengths of the materials. The SPV method was used to fill gaps in the knowledge of material parameters that had not been determined successfully by other characterization methods. The second project involved creating a 2D finite element model of a surface acoustic wave device. A basic form of the model with the expected impedance response curve was completed, and the model is ready to be further developed for analysis of MEMS photonic resonator devices.

  17. The Sun as you never saw it before

    NASA Astrophysics Data System (ADS)

    1997-02-01

    The remarkable images come from SOHO's visible-light coronagraph LASCO. It masks the intense rays from the Sun's surface in order to reveal the much fainter glow of the solar atmosphere, or corona. Operated with its widest field of view, in its C3 instrument, LASCO's unprecedented sensitivity enables it to see the thin ionized gas of the solar wind out to the edges of the picture, 22 million kilometres from the Sun's surface. Many stars are brighter than the gas, and they create the background scene. The results alter human perceptions of the Sun. Nearly 30 years ago, Apollo photographs of the Earth persuaded everyone of what until then they knew only in theory, that we live on a small planet. Similarly the new imagery shows our motion in orbit around the Sun, and depicts it as one star among - yet close enough to fill the sky emanations that engulf us. For many centuries even astrologers knew that the Sun was in Sagittarius in December and drifting towards the next zodiacal constellation, Capricornus. This was a matter of calculation only, because the Sun's own brightness prevented a direct view of the starfield. The SOHO-LASCO movie makes this elementary point of astronomy a matter of direct observation for the first time. The images are achievable only from a vantage point in space, because the blue glow of the Earth's atmosphere hides the stars during the day. A spacial allocation of observing time, and of data tranmission from the SOHO spacecraft, enabled the LASCO team to obtain large numbers of images over the period 22-28 December 1996. Since then, a sustained effort in image processing, frame by frame, has achieved a result of high technical and aesthetic quality. Only now is the leader of the LASCO team, Guenter Brueckner of the US Naval Research Laboratory, satisfied with the product and ready to authorize its release. "I spend my life examining the Sun," Brueckner says, "but this movie is a special thrill. For a moment I forget the years of effort that went into creating LASCO and SOHO, and leave aside the many points of scientific importance in the images, I am happy to marvel at a new impression of the busy star that gives us life, and which affects our environment in many ways that we are only now beginning to understand." Transatlantic cooperation The Solar and Heliospheric Observatory SOHO is a project of international cooperation between ESA and NASA. ESA and the European aerospace industry built the spacecraft, and NASA launched it on 2 December 1995. Operating 1,500,000 kilometres out on the sunward side of the Earth, near the position called Lagrangian point L1, SOHO has an uninterrupted view of the Sun from an undisturbed vantage point, and a precision of pointing which makes delicate observations possible. SOHO carries 12 sets of instruments provided by scientific teams, each led by a European or an American principal investigator. They study the solar interior by helioseismology, the solar atmosphere seen by ultraviolet and visible light, and the solar wind and energetic particles. There is much transatlantic collaboration within the various teams. Besides the Naval Research Laboratory in Washington, LASCO involves the Max-Planck-Institüt für Aeronomie at Lindau (Germany), the Unversity of Birmingham (England) and Laboratoire d'Astronomie Spatiale at Marseille (France). Sharing LASCO's electronic systems, and many operations and analyses, is SOHO's extreme ultraviolet imager EIT. This is the responsibility of a team led from Orsay (France) and it observes activity in the Sun's hot atmosphere related to the wider events seen by LASCO. Roger Bonnet, who presides over the multinational effort as ESA's Director of Science, shares the enthusiasm for the Christmas movie. "For the first time we see the Sun clearly among the stars, thanks to SOHO and LASCO," Bonnet comments. "Now when we say that the Sun is a typical star, and a key to understanding the whole Universe, that is no longer a theoretical statement but something everyone can see. The quality of the images confirms that SOHO is the finest and most stable spacecraft ever devoted to the study of the Sun." Features of the motion picture North is at the top of the scene, which corresponds with the orientation of the Sun as seen at midday in the northern hemisphere of the Earth. SOHO's progress in orbit around the Sun remains in step with the Earth's motion. It travels towards the right (west) in relation to the stars, during the period of observation. As a result, the Sun's position appears to shift to the left (eastwards) in front of the stars. LASCO C3 observes an area of the sky 32 times wider than the visible Sun itself. If you spread the fingers of one hand and hold them at arm's length towards the sky, they will span the 17-degree width of LASCO's field of view. For comparison, the Sun is less than half the width of your little finger. At the time of the observations, SOHO is looking towards the heart of the Milky Way Galaxy, which lies in the constellation of Sagittarius. The Milky Way, made by the light of billions of distant stars, forms a luminous band slanting down and to the right. Dark lanes seen in the Milky Way are real features familiar to astronomers. They are created by dust clouds in the disk of the Galaxy which obscure the distant stars. A doomed comet, previously unknown, enters on the left of the image on 22 December. Its path curves towards the Sun and on 23 December. Its path curves towards the Sun and on 23 December it disappears behind the occulting mask of the coronagraph. It fails to reappear on the far side of the Sun. Whether or not its trajectory took it directly towards the visible surface, the comet must have evaporated in Sun's atmosphere. It was one of a family of comets known as sungrazers, believed to be remnants of a large comet that that broke up perhaps 900 years ago. Other fragments were responsible for spectacular comet apparitions in 1843, 1882 and 1965. The object in the movie is called Comet SOHO 6. It is one of seven sungrazers discovered so far by LASCO, with its unparalleled view of the solar vicinity. Analyses of the comets'orbits, now in progress, are a prerequisite for their inclusion in the official record of comet discoveries. LASCO also provided unique pictures of Comet Hyakutake passing behind the Sun at the beginning of May 1996. Debris strewn from the tails of many comets makes a disk of dust around the Sun, in the ecliptic plane where the planets orbit. It scatters sunlight and is sometimes visible at twilight on the Earth, as the Zodiacal Light. In the raw images obtained by LASCO, the Zodiacal Light is brighter than the solar corona. Image processing has to subtract its effects precisely, to bring the solar wind and the Milky Way into plain view. Random flashes of light in the images are due to cosmic rays striking the detector. These should be regarded, not as blemishes, but as part of the scenery. Cosmic rays are energetic particles coming from exploded stars in the Milky Way, and variations in the solar wind influence their intensity in the vicinity of SOHO and the Earth. Operating beyond the Earth's magnetic field, which repels many particles, SOHO is more exposed to the cosmic rays. In the largest outburst from the Sun seen in the Christmas movie, a mass ejection causes billions of tonnes of gas to race out into space on the right-hand (western) side of the Sun. The origin of this event much lower in the Sun's atmosphere was evident in an expanding bubble seen in processed images from the extreme ultraviolet imager EIT. Coronagraph views obtained during the same Christmas period in the narrower fields of LASCO's C1 and C2 instruments also helped to reveal the Sun's complex behaviour. Coronal mass ejections are the hurricanes of space weather. SOHO is ideally placed and instrumented to report and even anticipate their origins in the Sun's atmosphere. Although the Sun is supposedly very quiet at present, being close to the minimum count of sunspots, LASCO observes so many outbursts large and small - roughly one a day - that scientists are having to think again about how to define a coronal mass ejection. SOHO's continuing success Later LASCO images, on 6 January 1997, revealed a large mass ejection directed towards the Earth. As it swelled it appeared as a halo around the Sun. The mass ejection reached SOHO itself less than four days later, and the solar-wind analyser CELIAS detected an acceleration in the solar wind, from 350 to more than 500 kilometres per second. Soon afterwards, American, Russian and Japanese satellites operating closer to the Earth registered the event, which caused a magnetic storm and bright auroras. The failure of an American TV satellite on 11 January may have been directly related to this event. Mass ejections and other upheavals on the Sun will become even commoner during the coming years, as the count of sunspots increases towards the expected maximum of solar activity in 2000-01. Meanwhile, SOHO is seeking the fundamental reason for the cycle of sunspot activity, which is essentially a magnetic phenomenon. One of the helioseismic instruments probing the solar interior, SOI/MDI, has detected a likely source for the Sun's puzzling magnetism. There may be a natural dynamo operating at the base of the turbulent outer region of the Sun, called the convective zone. This rotates about 7 per cent faster than the underlying and more cohesive region of dense gas, the radiative zone. With the spacecraft in excellent condition and their instruments performing beyond expectations, SOHO's scientists are urging ESA and NASA to allow them to continue their work beyond April 1998, when the initial year of their scientific operations will have been completed.

  18. Chop Saw SUCCESS!: "Crash Proofing" a Metalworking Lab

    ERIC Educational Resources Information Center

    Domermuth, David

    2004-01-01

    The Technology Department at Appalachian State University runs a metals lab to introduce students to basic metalworking processes. Many of the students have never worked with metal before. The class objectives call for teaching students metal properties, processing, and design problem solving. The average student is a 20-year-old junior whom…

  19. Fiber properties of saw and roller ginned naturally colored cotton

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Naturally colored cottons have economic and environmental appeal because they do not require dyeing. Naturally colored cottons do not have the same fiber length and strength as white cotton cultivars. To determine the optimal ginning process for colored fiber two Upland (G. hirsutim) colors were r...

  20. Germany As We Saw It. Third Edition, 1963.

    ERIC Educational Resources Information Center

    Stanford Univ., CA.

    Closeup studies of German life in the Stuttgart area are reported here by 79 participants of Stanford University's 1963 National Defense Education Act Second-Level Institute for Elementary and Secondary School Teachers held at Bad Boll, Germany. Elementary and secondary education, work and family life, and housing and housing developments are…

  1. See What Galileo Saw - And More! With Online Telescopes

    NASA Astrophysics Data System (ADS)

    Steel, Simon J.

    2008-05-01

    This presentation introduces the Galileo activity from MicroObservatory, an online robotic telescope network that can deliver images free of charge and within 24 hours to anyone with an email address. I will describe the MicroObservatory network, its free image processing software, and examples of how users can follow in Galileo's footsteps by making their own observations and comparing them both to Galileo's sketches and images from modern space telescopes and planetary missions. I will also describe a new "Observing with NASA portal to MicroObservatory that is being developed for IYA.

  2. See What Galileo Saw---And More! With Online Telescopes

    NASA Astrophysics Data System (ADS)

    Steel, S. J.

    2008-11-01

    This presentation introduces the Galileo activity from MicroObservatory, an online robotic telescope network that can deliver images free of charge and within 24 hours to anyone with an email address. I will describe the MicroObservatory network, its free image processing software, and examples of how users can follow in Galileo's footsteps by making their own observations and comparing them both to Galileo's sketches and images from modern space telescopes and planetary missions. I will also describe a new ``Observing with NASA'' portal to MicroObservatory that is being developed for IYA.

  3. Hole saw drill attachment has zero force reaction

    NASA Technical Reports Server (NTRS)

    Holmes, A. E.; Riley, R. H., Jr.

    1966-01-01

    Zero reaction tools require no force application by workers in space. The tool accomplishes hole cutting by holding the workpiece and feeding the cutting blade into and through it by forces entirely absorbed within the tool.

  4. Temperature and Strain Coefficient of Velocity for Langasite SAW Devices

    NASA Technical Reports Server (NTRS)

    Wilson, W. C.; Atkinson, G. M.

    2013-01-01

    Surface Acoustic Wave sensors on Langasite substrates are being investigated for aerospace applications. Characterization of the Langasite material properties must be performed before sensors can be installed in research vehicles. The coefficients of velocity for both strain and temperature have been determined. These values have also been used to perform temperature compensation of the strain measurements.

  5. Performance evaluation of algorithms for SAW-based temperature measurement.

    PubMed

    Schuster, Stefan; Scheiblhofer, Stefan; Reindl, Leonhard; Stelzer, Andreas

    2006-06-01

    Whenever harsh environmental conditions such as high temperatures, accelerations, radiation, etc., prohibit usage of standard temperature sensors, surface acoustic wave-based temperature sensors are the first choice for highly reliable wireless temperature measurement. Interrogation of these sensors is often based on frequency modulated or frequency stepped continuous wave-based radars (FMCW/FSCW). We investigate known algorithms regarding their achievable temperature accuracy and their applicability in practice. Furthermore, some general rules of thumb for FMCW/FSCW radar-based range estimation by means of the Cramer-Rao lower bound (CRLB) for frequency and phase estimation are provided. The theoretical results are verified on both simulated and measured data. PMID:16846150

  6. "I Saw the Universe and I Saw the World": Exploring Spiritual Literacy with Young Children in a Primary Classroom

    ERIC Educational Resources Information Center

    Binder, Marni J.

    2011-01-01

    This paper explores the concept of promoting spiritual literacy as viewed through the eyes of a holistic educator of young children in an inner-city primary classroom. Similar to discussions of spirituality in education, the idea of spiritual literacy is often elusive and can create discomfort and tensions. Drawing on stories of experience, the

  7. '"We Saw Inhumanity Close up." What Is Gained by School Students from Scotland Visiting Auschwitz?

    ERIC Educational Resources Information Center

    Cowan, Paula; Maitles, Henry

    2011-01-01

    As the education for citizenship agenda continues to impact on schools in the UK and with the Holocaust Educational Trust (HET) in conjunction with the Scottish Government introducing its Lessons From Auschwitz (LFA) project for students and teachers in Scotland, this article focuses on the Scottish context and investigates the school processes by

  8. Interesting differences between CH4 and d18Oatm records of bipolar see-saw activity

    NASA Astrophysics Data System (ADS)

    Severinghaus, Jeffrey; Baggenstos, Daniel; Rhodes, Rachael; Brook, Edward

    2014-05-01

    Abrupt changes in atmospheric methane concentration have long been used to infer changes in low-latitude hydrology. A lesser-used tracer is the oxygen-18 content of atmospheric dioxygen (d18Oatm), which is produced by photosynthesis and records the O-18 content of chloroplast water among other variables. Observations from ice core trapped air records suggest that strong Asian monsoons produce dioxygen with a relatively negative d18Oatm, whereas periods of weak Asian monsoon rainfall and strong southern hemisphere monsoons are characterized by relatively positive d18Oatm (Severinghaus et al., 2009, Science). Generally, CH4 and d18Oatm are anticorrelated, with high CH4 and negative d18Oatm during times of northern hemisphere warmth, strong Asian monsoons, and the bipolar seesaw in its "warm north" mode. However, interesting exceptions to this pattern occur during Heinrich Stadials and during the initial phases of the last deglaciation. Here, ice core data suggest episodes in which CH4 rise is not associated with negative d18Oatm, but instead positive d18Oatm. It is suggested that these intervals can be explained as being times of strong southern hemisphere low-latitude rainfall, which creates the positive values in d18Oatm. We hypothesize that dioxygen produced in southern hemisphere locales generally has higher O-18 content, due to the higher O-18 content of chloroplast water and the prevailing precipitation O-18 in those regions. In summary, we hypothesize that d18O of photosynthetic O2 is a more monotonic function of latitude, compared with methane production, which can be bimodally produced in the low latitudes of both hemispheres.

  9. Warpage Analysis of Silicon Wafer in Ingot Slicing by Wire-Saw Machine

    NASA Astrophysics Data System (ADS)

    Yamada, Toshiro; Kinai, Fumiaki; Ichikawa, Takesh; Yokoyama, Atsushi; Fukunaga, Moritaka; Ohshita, Takashi

    2004-06-01

    It is possible thermal expansion from heat generation by slicing deforms a single-crystal silicon ingot but the authors can find no report on the point. In addition, numerical analysis is useful to clarify the mechanism of wafer warping but no paper has been reported the numerical analysis from the start to end of the wafer slicing process. The authors carried out experiments for the wafer slicing. In addition, a finite element analysis was carried out in order to solve the warping mechanism from the start to end of the wafer slicing process. The warp of wafer in the vertical direction was 6.05 ? m in the experiment whereas the warp in the finite element analysis was 5.30 ? m. The result by the finite element analysis gave good agreement with experimental one. This paper suggests that thermal expansion of the ingot has great influence on the warp of wafer.

  10. What the Butler Saw: Lee Daniels's Studies in Biography and History

    ERIC Educational Resources Information Center

    Beck, Bernard

    2014-01-01

    The movie "Lee Daniels' The Butler" is an example of a work that is meant not only to entertain but to convey an important attitude and offer important viewpoints. The movie deals with a deep issue in the history of movies and the history of the country: racial inequality. Three issues are discussed in this article: (a) African

  11. They Saw a Movie: Long-Term Memory for an Extended Audiovisual Narrative

    ERIC Educational Resources Information Center

    Furman, Orit; Dorfman, Nimrod; Hasson, Uri; Davachi, Lila; Dudai, Yadin

    2007-01-01

    We measured long-term memory for a narrative film. During the study session, participants watched a 27-min movie episode, without instructions to remember it. During the test session, administered at a delay ranging from 3 h to 9 mo after the study session, long-term memory for the movie was probed using a computerized questionnaire that assessed

  12. They Went, They Saw, They Learned: Medical Students' Reflections on Community Clinic Visits

    ERIC Educational Resources Information Center

    Beylefeld, Adriana A.

    2014-01-01

    Medicine has become a profession with increasing accountability to the needs of society. To meet this need, real-world, community-located experiences and reflection are frequently used to promote students' learning and personal growth. This article reports first-year medical students' reflective writing after visiting a primary…

  13. The see-saw a vertical-lift incubator designed for channel catfish egg masses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Channel catfish egg masses are typically incubated in baskets that are suspended in water that is agitated with rotating or oscillating paddles. We designed and tested a new vertical-lift incubator (the “See-Saw”) to incubate channel catfish egg masses. Preliminary research in commercial hatcheries...

  14. '"We Saw Inhumanity Close up." What Is Gained by School Students from Scotland Visiting Auschwitz?

    ERIC Educational Resources Information Center

    Cowan, Paula; Maitles, Henry

    2011-01-01

    As the education for citizenship agenda continues to impact on schools in the UK and with the Holocaust Educational Trust (HET) in conjunction with the Scottish Government introducing its Lessons From Auschwitz (LFA) project for students and teachers in Scotland, this article focuses on the Scottish context and investigates the school processes by…

  15. Soldering Process and Cutting Performance of Micro SAW Wire Bonded with Diamond Grains

    NASA Astrophysics Data System (ADS)

    Kamiya, Osamu; Miyano, Yasuyuki; Takahashi, Mamoru; Oga, Yuichi; Chen, Zhan Wen; Funaoka, Kennji

    This paper will demonstrate that diamond grains can be bonded to W micro-wires (AD wires) with a specially developed metal solder in a continuous process capable of producing the wire of 1000 m in length. Cutting experiments using a specially designed cutting machine have been conducted. We will demonstrate that AD wire can cut WC (HV2500) and that AD wire performs superior compared to other commercial cutting wires bonded with diamond grains using either Ni plating or resin type. It has also been found that for wire diameter less than 100 m cutting life of the wire was short and failed in a torsion fracture mode. This will be explained by comparing the friction induced torsion to the twist strength of the wire.

  16. ENSO-driven carbon see saw in the Indo-Pacific

    NASA Astrophysics Data System (ADS)

    Rixen, Tim; Ittekkot, Venugopalan; Herunadi, Bambang; Wetzel, Patrick; Maier-Reimer, E.; Gaye-Haake, Birgit

    2006-04-01

    The sediment trap experiments have been carried out during the 2001/2002 El Nio/La Nia transition in the monsoon-driven and freshwater influenced upwelling system off South Java. The results indicate that enhanced precipitation rates and associated river discharges increase the CO2-uptake of the biological pump by increasing the organic carbon export and reducing the carbonate precipitation. The freshwater, furthermore, forms a buoyant low salinity surface layer that caps off the nutrient and CO2-rich subsurface waters which shortens the upwelling season during wet La Nia conditions. A reduced capping-effect during dryer El Nio conditions strengthens the upwelling and as shown by our model results increase CO2 emission into the atmosphere along the freshwater influenced continental margins in SE Asia. By contrast El Nio weakens upwelling and reduces the CO2 emission in the equatorial Pacific Ocean.

  17. Utility Theory for Evaluation of Optimal Process Condition of SAW: A Multi-Response Optimization Approach

    SciTech Connect

    Datta, Saurav; Biswas, Ajay; Bhaumik, Swapan; Majumdar, Gautam

    2011-01-17

    Multi-objective optimization problem has been solved in order to estimate an optimal process environment consisting of optimal parametric combination to achieve desired quality indicators (related to bead geometry) of submerged arc weld of mild steel. The quality indicators selected in the study were bead height, penetration depth, bead width and percentage dilution. Taguchi method followed by utility concept has been adopted to evaluate the optimal process condition achieving multiple objective requirements of the desired quality weld.

  18. Utility Theory for Evaluation of Optimal Process Condition of SAW: A Multi-Response Optimization Approach

    NASA Astrophysics Data System (ADS)

    Datta, Saurav; Biswas, Ajay; Bhaumik, Swapan; Majumdar, Gautam

    2011-01-01

    Multi-objective optimization problem has been solved in order to estimate an optimal process environment consisting of optimal parametric combination to achieve desired quality indicators (related to bead geometry) of submerged arc weld of mild steel. The quality indicators selected in the study were bead height, penetration depth, bead width and percentage dilution. Taguchi method followed by utility concept has been adopted to evaluate the optimal process condition achieving multiple objective requirements of the desired quality weld.

  19. Defect detection in partially completed SAW and TIG welds using online radioscopy and image processing

    NASA Astrophysics Data System (ADS)

    Bonser, Gary R.; Lawson, Shaun W.

    1998-03-01

    An application of machine vision applied to the analysis of radioscopic images of incomplete weld geometries is described. The rationale of the work is to identify weld defects as soon as they are produced, thereby reducing the costs of any subsequent repairs. Existing methods of weld and defect identification are compared, leading to the development of filtering and 'window' based variance operator for segmentation of suspect defect areas inside the weld region is described. The software and radioscopic imaging system have been benchmarked through a series of demonstration trials on both 80 mm thick carbon steel submerged arc welded testpieces, and 25mm thick carbon steel tungsten inert gas welded testpieces. The range of intentionally implanted defects, from root cracks to lack of side wall fusion, were detected with an overall accuracy of 87 percent, and classified in terms of defect size, shape, and position within the weld region.

  20. Influence of macrostructure on tensile properties of multipass SAW C-Mn steel deposits

    NASA Astrophysics Data System (ADS)

    Yongyuth, P.; Ghosh, P. K.; Gupta, P. C.; Patwardhan, A. K.; Prakash, Satya

    1993-06-01

    Blocks of 'all weld' metal were prepared by a multipass submerged arc process, using a C-Mn filler wire, at different welding currents and speeds by keeping the arc voltage constant. The variation in welding parameters was found to alter the macrostructure primarily by influencing its co-axial dendrite content. The chemical composition and hardness of the dendritic and the heat affected regions were affected little by the welding parameters. A dendrite content up to 37%, had no significant effect on the tensile properties. However an increase in it beyond 37% was found to enhance the UTS and YS and reduce percent elongation. The tensile strength was found to be a maximum in the L orientation and a minimum in the S direction. The use of post-weld heat treatment (PWHT) at 873 K caused spheroidization of cementite there by somewhat reducing the hardness and strength. The treatment while not affecting the basic dendritic morphology reduced the observed difference in tensile properties along the L, T and S directions. Implications of the data vis-a-vis industrial applications have been discussed.

  1. As the Europeans Saw Them: The Aleuts of the Eighteenth Century, Social Studies Unit, Book II.

    ERIC Educational Resources Information Center

    Partnow, Patricia H., Comp.

    This booklet is intended for use as reading material for the social studies unit, The Aleuts of the Eighteenth Century. Excerpts from journals of seven 18th-century explorers or travelers describe the inhabitants of the Aleutian Islands. The accounts have been translated from original notes kept by members of the Russian navy, ship commanders, a

  2. Investigations of the polyaniline and nafion bilayer sensor structure in SAW system

    NASA Astrophysics Data System (ADS)

    Jakubik, W. P.; Urba?czyk, M.; Maciak, E.

    2006-11-01

    Presented here are the preliminary results concerning an investigations of a novel bilayer sensor structure of polyaniline and Nafion as a toxic gas sensors in a Surface Acoustic Wave system. The investigations were performed with different concentrations of the various toxic gases like SO{2}, CO, H{2}S and ammonia (NH{3}) in synthetic dry air. The prototype polyaniline and nafion bilayer structure has been manufactured by two deposition technologies: 180 nm of PANI by PVD technology and thin Nafion film by spin coating technology and specific process of annealing. A good interaction with various concentrations of ammonia for the bilayer structure (PANI film with Nafion) has been observed.

  3. NASA Lewis Helps Develop Advanced Saw Blades for the Lumber Industry

    NASA Technical Reports Server (NTRS)

    1998-01-01

    NASA Lewis Research Center's Structures and Material Divisions are centers of excellence in high-temperature alloys for aerospace applications such as advanced aircraft and rocket engines. Lewis' expertise in these fields was enlisted in the development of a new generation of circular sawblades for the lumber industry to use in cutting logs into boards. The U.S. Department of Agriculture's (USDA) Forest Products Laboratory and their supplier had succeeded in developing a thinner sawblade by using a nickel-based alloy, but they needed to reduce excessive warping due to residual stresses. They requested assistance from Lewis' experts, who successfully eliminated the residual stress problem and increased blade strength by over 12 percent. They achieved this by developing an innovative heat treatment based on their knowledge of nickel-based superalloys used in aeropropulsion applications.

  4. One GHz leaky SAW velocity of metal layers and bilayers evaporated onto fused quartz

    NASA Technical Reports Server (NTRS)

    Walikainen, Dale

    1992-01-01

    An acoustic microscope operating at 1 GHz was used to determine the surface acoustic wave velocities v of thin film metal layers and metal bilayers deposited onto fused quartz. V(0)'s influence was reduced by gating. This produced a calibrated accuracy of 3 percent. A program was constructed from the explicitly solved 6 x 6 theoretical determinant. Single film thicknesses were decided upon by using this theory to produce a v equal to a standard. Since the single film v's were linear with respect to their thickness, half the single film thicknesses were used for the bilayered films. The velocities for these bilayered films agreed with theory. This experimentally confirms the theoretical technique used here to examine bilayered systems, or a prototype composite interphase. No discrepancy was seen for gold films as others have reported. V(z) seemed insensitive to the formation of intermetallics or CuO. Some annealed and unannealed platinum films did not change the v from that of fused quartz. Two platinum films whose v's were in agreement with theory peeled off with the tape test.

  5. Surface acoustic wave (SAW) microsensor array for measuring VOCs in drinking water.

    PubMed

    Groves, W A; Grey, A B; O'Shaughnessy, P T

    2006-09-01

    Exposure to volatile organic chemicals (VOCs) in drinking water has been linked to a number of adverse health effects including cancer, liver, and kidney damage. However, the large number of potential contaminants and the cost and complexity of existing analytical methods limits the extent to which water quality is routinely characterized. This project focused on the laboratory development and evaluation of an instrument for field analysis of VOCs in drinking water. The instrument is based on an array of six polymer-coated surface-acoustic-wave microsensors. A test-set consisting of dichloromethane, chloroform, 1,1,1-trichloroethane, perchloroethylene, and m-xylene was used in a series of experiments designed to optimize the purge-trap preconcentration system, calibrate the instrument over the concentration range of 0.2-2 times the USEPA maximum contaminant levels (MCLs), and compare results to those of a reference laboratory. The primary goal was to develop a cost-effective alternative for on-site evaluation of VOCs in water. Calibration and evaluation test results for spiked water samples demonstrate adequate sensitivity for 19 of the 21 regulated VOCs considered using a ten minute sampling and analysis cycle. Monte Carlo simulations characterized the performance of trained artificial neural networks (ANNs) which had correct classification rates of 99%, 90%, and 80% for the five individual test-set vapors and their binary and ternary mixtures, respectively. These results demonstrate the excellent potential of this technology for addressing the need for improved VOC field-screening methods for water supplies. PMID:16951753

  6. Monitoring complex formation in the blood-coagulation cascade using aptamer-coated SAW sensors.

    PubMed

    Gronewold, T M A; Glass, S; Quandt, E; Famulok, M

    2005-04-15

    Specific binding of the anticoagulants heparin and antithrombin III to the blood clotting cascade factor human thrombin was recorded as a function of time with a Love-wave biosensor array consisting of five sensor elements. Two of the sensor elements were used as references. Three sensor elements were coated with RNA or DNA aptamers for specific binding of human thrombin. The affinity between the aptamers and thrombin, measured using the biosensor, was within the same range as the value of K(D) measured by filter binding experiments. Consecutive binding of the thrombin inhibitors heparin, antithrombin III or the heparin-antithrombin III complex to the immobilized thrombin molecules, and binding of a ternary complex of heparin, anithrombin III, and thrombin to aptamers was evaluated. The experiments showed attenuation of binding to thrombin due to heparin-antithrombin III complex formation. Binding of heparin activated the formation of the inhibitory complex of antithrombin III with thrombin about 2.7-fold. Binding of the DNA aptamer to exosite II appeared to inhibit heparin binding to exosite I. PMID:15741074

  7. TALSPEAK CURVE: AN ILLUSTRATION OF A SEE-SAW EFFECT IN SEPARATIONS

    SciTech Connect

    Peter Zalupski; Leigh Martin

    2010-11-01

    A superbly balanced thermodynamic struggle for metal ion coordination by aqueous aminopolycarboxylate reagent, DTPA, and non-aqueous organophosphorous phase transfer reagent, HDEHP, affords the separation of trivalent actinides from trivalent lanthanides under the umbrella of the Talspeak liquid-liquid distribution process. This thermodynamic relationship has been linked to an analogous “see-saw” behavior, where the balance is distorted when either of the key complexing players is subject to adverse conditions that interfere with their optimal operation. The thermodynamic balance is tipped in favour of HDEHP whenever increased acidity of the aqueous solution out-competes the metal ion complexation by aqueous complexing agent. Also enhanced steric crowding may switch-off efficient coordination of the metal ion. When HDEHP is depolymerised due to the presence of aliphatic alcohol in the organic phase its phase transferring power is diminished. Such complication paves way for DTPA to establish its dominance on the distribution of trivalent metal ions in the 2-phase system. The illustrated sensitivity of the thermodynamic balance between DTPA and HDEHP in Talspeak-type systems may serve as informative tool when studying less-predictable realms of Talspeak chemistry.

  8. PSAW/MicroSWIS [Microminiature Surface Acoustic Wave (SAW) based Wirelesss Instrumentation System

    NASA Technical Reports Server (NTRS)

    Heermann, Doug; Krug, Eric

    2004-01-01

    This Final Report for the PSAW/MicroSWIS Program is provided in compliance with contract number NAS3-01118. This report documents the overall progress of the program and presents project objectives, work carried out, and results obtained. Program Conceptual Design Package stated the following objectives: To develop a sensor/transceiver network that can support networking operations within spacecraft with sufficient bandwidth so that (1) flight control data, (2) avionics data, (3) payload/experiment data, and (4) prognostic health monitoring sensory information can flow to appropriate locations at frequencies that contain the maximum amount of information content but require minimum interconnect and power: a very high speed, low power, programmable modulation, spread-spectrum radio sensor/transceiver.

  9. HIGH SURFACE AREA POLYMER COATINGS FOR SAW-BASED CHEMICAL SENSOR APPLICATIONS. (R826648)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  10. "Remember where you last saw that card": children's production of external symbols as a memory aid.

    PubMed

    Eskritt, Michelle; Lee, Kang

    2002-03-01

    Four experiments examined the age at which children start to use external symbols to aid their memory and how external symbol use affects both their memory performance and information allocation strategies. In Experiment 1, children in Grades 1, 3, 5, and 7 played a memory card game (Concentration) twice, once with the opportunity to make notes to aid performance and once without the opportunity. Grades I and 3 students tended to produce nonmnemonic notations, whereas Grades 5 and 7 students were more likely to produce functional, adultlike notations that aided performance in the task. In Experiments 2a and 2b, unexpected removal of children's notations led to a decrease in performance. suggesting that the spontaneously produced notations were being used as an external store rather than as an aid to encoding information. Experiment 3 examined whether all information was placed in external storage or if some types of information remained in memory. Grade 7 students who had their notations unexpectedly taken away were able to recognize the identity of the cards they had previously seen but had more difficulty remembering their locations. They appeared to place the location information mainly in external storage while retaining the identity information in memory. These results suggest that in mid-childhood, children begin to distribute information actively between internal and external memory storage. PMID:11881760

  11. The Income Volatility See-Saw: Implications for School Lunch. Economic Research Report Number 23

    ERIC Educational Resources Information Center

    Newman, Constance

    2006-01-01

    Income volatility challenges the effectiveness of the safety net that USDA food assistance programs provide low-income families. This study examines income volatility among households with children and the implications of volatility for eligibility in the National School Lunch Program (NSLP). The results show that income volatility was higher for…

  12. They Went, They Saw, They Learned: Medical Students' Reflections on Community Clinic Visits

    ERIC Educational Resources Information Center

    Beylefeld, Adriana A.

    2014-01-01

    Medicine has become a profession with increasing accountability to the needs of society. To meet this need, real-world, community-located experiences and reflection are frequently used to promote students' learning and personal growth. This article reports first-year medical students' reflective writing after visiting a primary

  13. Comparison of high-speed roller and saw ginning on Texas high plains cotton

    Technology Transfer Automated Retrieval System (TEKTRAN)

    New high-quality cotton cultivars have been adopted in the Southern High Plains recently and, as a result, interest has grown in finding harvest and ginning practices that better preserve fiber quality. Advancements in roller ginning technology have increased the ginning rate of some roller gins to ...

  14. Quality Comparison of Saw and Roller Ginning Three Mid-South Cultivars

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Three cultivars; Fibermax 960 BR, Deltapine 147 RF, and Deltapine 164 B2RF; were grown normally at Stoneville, MS and spindle harvested during the 2008 crop year. The cottons were processed with the same precleaning: dryer at 250F, cylinder cleaner, stick machine, dryer at 240F, and cylinder clea...

  15. Monolithic integration of GaAs SAW chemical microsensor arrays and detection electronics

    SciTech Connect

    CASALNUOVO,STEPHEN A.; HIETALA,VINCENT M.; HELLER,EDWIN J.; ASON,GREGORY CHARLES; BACA,ALBERT G.

    2000-04-17

    The authors describe the integration of an array of surface acoustic wave delay line chemical sensors with the associated RF microelectronics such that the resulting device operates in a DC in/DC out mode. The microelectronics design for on-chip RF generation and detection is presented. Both hybrid and monolithic approaches are discussed. This approach improves system performance, simplifies packaging and assembly, and significantly reduces overall system size. The array design can be readily scaled to include a large number of sensors.

  16. Old Saws and New Materials: A Consideration of Some Ethical Problems.

    ERIC Educational Resources Information Center

    Morse, John F.

    1968-01-01

    Reports of job-hopping, opportunism, grantsmanship, and wheeling-dealing, based on the availability of federal research funds, by university faculty has created much concern in governmental and educational circles about the ethical problems these activities pose for the academic profession. In 1963, the Office of Science and Technology(OST) and

  17. "Hey, I Saw Your Grandparents at Walmart": Teacher Education for Rural Schools and Communities

    ERIC Educational Resources Information Center

    Eppley, Karen

    2015-01-01

    This is a case study about how teacher education might better prepare rural teacher candidates for rural schools. Parents, teachers, community members, and students associated with a rural school described what is important in the preparation of teachers for today's rural schools. Their goals and wishes for their children's school and

  18. "I Saw it in a Different Light": International Learning Experiences in Baccalaureate Nursing Education.

    ERIC Educational Resources Information Center

    Walsh, Linda V.; DeJoseph, Jeanne

    2003-01-01

    Ten nursing students and two faculty mentors participated in an immersion experience in Guatemala. Themes from interviews included the experience of being "other," growth as a professional nurse, and expansion of world views. (Contains 16 references.) (SK)

  19. "Such a smoking nation as this I never saw...": smoking, nationalism, and manliness in nineteenth-century Hungary.

    PubMed

    Maxwell, Alexander

    2006-01-01

    Tobacco smoking became an important marker of Hungarian national identity during the nineteenth century. this national symbol ultimately had an economic origin: Hungarian tobacco producers resisted the tobacco monopoly of the Habsburg central government, and led an ultimately successful consumer boycott of Austrian products. Tobacco nationalism, however, became a common theme in Hungarian popular culture in its own right, as tobacco use came to symbolize community and fraternity. The use of tobacco was also highly gendered; smoking as a metaphor for membership shows that the Hungarian nation was a gender-exclusive "national brotherhood." PMID:20058399

  20. Channel catfish hatchery production efficiency using a vertical-lift incubator the see-saw at various egg loading densities

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Channel catfish spawns are typically incubated in ¼-in mesh baskets suspended in water that is agitated with paddles positioned between baskets. We tested a new vertical-lift incubator (the “See-Saw”) to incubate channel catfish spawns. Previous research demonstrated that when loaded with spawns at...

  1. They Know I Saw It: Evaluation Apprehension and Diffusion of Responsibility in Bystander Reactions to a Violent Crime.

    ERIC Educational Resources Information Center

    Gottlieb, Avi; Schwartz, Shalom H.

    Male and female bystanders witnessed a violent theft in the course of a bogus "ESP Experiment." In addition to the subjects' sex, two experimental manipulations were orthogonally crossed. The subject was either the only one to witness the emergency, or witnessed it with an additional participant (diffusion of responsibility), and the subject's

  2. COGEMA Experience on Retrieving and Automatically Remote Cutting Large Metallic Structures Using Special Saw During Nuclear Decommissioning Operations

    SciTech Connect

    Bodin, F.; Barandas, C.

    2002-02-26

    Used spent fuel baskets have been stored in the La Hague North-West concrete-lined pits until decommissioning. In 1998, COGEMA decided to retrieve, cut and condition these spent fuel baskets. This paper describes the experience gained, since the start up of this operation in 1999, discusses resulting dosimetry and waste produced, during retrieving and remotely cutting of LL activity large metallic structures. This process result in significantly lower exposures to workers in the D and D operations. In addition the work was carried out in an environmentally safe manner with reasonable financial costs.

  3. Optimization of the Depth of Penetration by Welding Input Parameters in SAW Process Using Response Surface Methodology

    NASA Astrophysics Data System (ADS)

    Kazemi, Mohsen; Aghakhani, Masood; Haghshenas-Jazi, Ehsan; Behmaneshfar, Ali

    2016-02-01

    The aim of this paper is to optimize the depth of penetration with regard to the effect of MgO nanoparticles and welding input parameters. For this purpose, response surface methodology (RSM) with central composite rotatable design (CCRD) was used. The welding current, arc voltage, nozzle-to-plate distance, welding speed, and thickness of MgO nanoparticles were determined as the factors, and depth of penetration was considered as the response. Quadratic polynomial model was used for determining the relationship between the response and factors. A reduced model was obtained from the data which the values of R 2, R 2 (pred), and R 2 (adj) of this model were 92.05, 69.05, and 86.31 pct, respectively. Thus, this model was suitable, and it was used to determine the optimum levels of factors. The results show that the welding current, arc voltage, and nozzle-to-plate distance factors should be adjusted in high level, and welding speed and thickness of MgO nanoparticles factors should be adjusted in low level.

  4. I saw where you have been-The topography of human demonstration affects dogs' search patterns and perseverative errors.

    PubMed

    Péter, András; Topál, József; Miklósi, Ádám; Pongrácz, Péter

    2016-04-01

    Performance in object search tasks is not only influenced by the subjects' object permanence ability. For example, ostensive cues of the human manipulating the target markedly affect dogs' choices. However, the interference between the target's location and the spatial cues of the human hiding the object is still unknown. In a five-location visible displacement task, the experimental groups differed in the hiding route of the experimenter. In the 'direct' condition he moved straight towards the actual location, hid the object and returned to the dog. In the 'indirect' conditions, he additionally walked behind each screen before returning. The two 'indirect' conditions differed from each other in that the human either visited the previously baited locations before (proactive interference) or after (retroactive interference) hiding the object. In the 'indirect' groups, dogs' performance was significantly lower than in the 'direct' group, demonstrating that for dogs, in an ostensive context, spatial cues of the hider are as important as the observed location of the target. Based on their incorrect choices, dogs were most attracted to the previously baited locations that the human visited after hiding the object in the actual trial. This underlines the importance of retroactive interference in multiple choice tasks. PMID:26869220

  5. The mechanical properties of 2. 25Cr-1Mo weld metals deposited by the SAW-NG process

    SciTech Connect

    Chandel, R.; Gianetto, R.F.; Knight, R.F.; McGrath, J.A.; Orr, R.F.

    1985-09-01

    A series of narrow gap welds were prepared in 2.25Cr-1Mo steel plate using the submerged arc, narrow gap process with a Miller square wave ac 1000 power source. The notch toughness properties were assessed in the PWHT condition and after a temperembrittlement step-cooling treatment. Optimum notch toughness properties (>54 J at -40C) were achieved in the PWHT condition in welds with a low oxygen and sulfur content (total <0.035 pct), a fine bainitic microstructure, and a high (approx. =80 pct) proportion of recrystallized structure. For welds subject to the temper-embrittlement step-cooling treatment, the upward shift in Charpy transition temperature was of the order of 20 to 25C, irrespective of the levels of impurity elements, P, Sn, Sb, and As.

  6. Diffraction of a surface optical wave in an optical slab waveguide by a surface acoustic wave /SAW/

    NASA Astrophysics Data System (ADS)

    Parygin, V. N.; Tankovskii, N. S.

    1982-12-01

    A general equation is formulated for the interaction of a light wave and a surface acoustic wave in an optical slab waveguide, and a solution is obtained which determines the light intensity in all the possible modes and diffraction orders. It is shown that there is an analogy between light diffraction in a multimode optical waveguide and light diffraction in an anisotropic medium.

  7. The "See-saw" - A High-intensity Catfish Egg Incubator Designed to Save Space and Conserve Water

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Catfish spawns (egg masses) have been incubated and hatched in much the same way for nearly a century. Spawns are placed in ¼”-mesh hardware cloth baskets suspended in metal troughs and water is circulated with paddles placed between the baskets. While this practical system has apparently worked wel...

  8. FEM simulation of Rayleigh waves for CMOS compatible SAW devices based on AlN/SiO?/Si(100).

    PubMed

    Kaletta, Udo Christian; Wenger, Christian

    2014-01-01

    A simulation study of Rayleigh wave devices based on a stacked AlN/SiO?/Si(100) device was carried out. Dispersion curves with respect to acoustic phase velocity, reflectivity and electromechanical coupling efficiency for tungsten W and aluminium Al electrodes and different layer thicknesses were quantified by 2D FEM COMSOL simulations. Simulated acoustic mode shapes are presented. The impact of these parameters on the observed Rayleigh wave modes was discussed. High coupling factors of 2% and high velocities up to 5000 m/s were obtained by optimizing the AlN/SiO? thickness ratio. PMID:23684473

  9. The First Time Ever I Saw Your Feet: Inversion Effect in Newborns' Sensitivity to Biological Motion

    ERIC Educational Resources Information Center

    Bardi, Lara; Regolin, Lucia; Simion, Francesca

    2014-01-01

    Inversion effect in biological motion perception has been recently attributed to an innate sensitivity of the visual system to the gravity-dependent dynamic of the motion. However, the specific cues that determine the inversion effect in naïve subjects were never investigated. In the present study, we have assessed the contribution of the local…

  10. Real-time monitoring of calcium carbonate and cationic peptide deposition on carboxylate-SAM using a microfluidic SAW biosensor

    PubMed Central

    Pohl, Anna

    2014-01-01

    Summary A microfluidic biosensor with surface acoustic wave technology was used in this study to monitor the interaction of calcium carbonate with standard carboxylate self-assembled monolayer sensor chips. Different fluids, with and without biomolecular components, were investigated. The pH-dependent surface interactions of two bio-inspired cationic peptides, AS8 and ES9, which are similar to an extracellular domain of the chitin synthase involved in mollusc shell formation, were also investigated in a biological buffer system. A range of experimental conditions are described that are suitable to study non-covalent molecular interactions in the presence of ionic substances, such as, mineral precursors below the solubility equilibrium. The peptide ES9, equal to the mollusc chitin synthase epitope, is less sensitive to changes in pH than its counterpart AS8 with a penta-lysine core, which lacks the flanking acidic residues. This study demonstrates the extraordinary potential of microfluidic surface acoustic wave biosensors to significantly expand our experimental capabilities for studying the principles underlying biomineralization in vitro. PMID:25383294

  11. Analysis of chain saw lubricating oils commonly used in Thailand's southern border provinces for forensic science purpose.

    PubMed

    Choodum, Aree; Tripuwanard, Kijja; Daeid, Niamh Nic

    2014-08-01

    In recent years, Thailand's southern border provinces (Malay-Muslim-majority border provinces) have become the scene of violence and insurgency. One of the attack patterns is the blocking of roads with perennial plants followed by planned attacks using improvised explosive devices (IEDs) or weapons on first responders. Containers of viscous dark lubricating oil and traces of lubricants on the felled trees were usually found at the scene. These were suspected to be chain oil lubricant from the chainsaws used to cut down the trees used for the roadblock. This work aimed to differentiate the chromatographic patterns of used lubricating oils available in automobile repair shops from various locations across Thailand's southern border provinces. Lubricating oils were analyzed using gas chromatography/flame ionization detector (GC/FID) every two weeks to study their variation in chemical compositions over time. The results obtained from GC/FID were normalized for differentiation. This included four two-stroke, six four-stroke, and three recycled oils. Two lubricating oils found at an incident scene were also analyzed and the results compared with the chain oil from five seized chainsaws. PMID:24875837

  12. Hybrid method for the precise calculation of the general dyadic Greens functions for SAW and leaky wave substrates.

    SciTech Connect

    Branch, Darren W.

    2008-05-01

    Recently, the generalized method for calculation of the 16-element Green's function for analysis of surface acoustic waves has proven crucial to develop more sophisticated transducers. The generalized Green's function provides a precise relationship between the acoustic stresses and electric displacement on the three mechanical displacements and electric potential. This generalized method is able to account for mass loading effects which is absent in the effective permittivity approach. However, the calculation is numerically intensive and may lead to numerical instabilities when solving for both the eigenvalues and eigenvectors simultaneously. In this work, the general eigenvalue problem was modified to eliminate the numerical instabilities in the solving procedure. An algorithm is also presented to select the proper eigenvalues rapidly to facilitate analysis for all types of acoustic propagation. The 4 x 4 Green's functions and effective permittivities were calculated for materials supporting Rayleigh, leaky, and leaky longitudinal waves as demonstration of the method.

  13. Interfacing low-energy SAW nebulization with Liquid Chromatography-Mass Spectrometry for the analysis of biological samples

    PubMed Central

    Tveen-Jensen, Karina; Gesellchen, Frank; Wilson, Rab; Spickett, Corinne M.; Cooper, Jonathan M.; Pitt, Andrew R.

    2015-01-01

    Soft ionization methods for the introduction of labile biomolecules into a mass spectrometer are of fundamental importance to biomolecular analysis. Previously, electrospray ionization (ESI) and matrix assisted laser desorption-ionization (MALDI) have been the main ionization methods used. Surface acoustic wave nebulization (SAWN) is a new technique that has been demonstrated to deposit less energy into ions upon ion formation and transfer for detection than other methods for sample introduction into a mass spectrometer (MS). Here we report the optimization and use of SAWN as a nebulization technique for the introduction of samples from a low flow of liquid, and the interfacing of SAWN with liquid chromatographic separation (LC) for the analysis of a protein digest. This demonstrates that SAWN can be a viable, low-energy alternative to ESI for the LC-MS analysis of proteomic samples. PMID:25978651

  14. Real-time monitoring of calcium carbonate and cationic peptide deposition on carboxylate-SAM using a microfluidic SAW biosensor.

    PubMed

    Pohl, Anna; Weiss, Ingrid M

    2014-01-01

    A microfluidic biosensor with surface acoustic wave technology was used in this study to monitor the interaction of calcium carbonate with standard carboxylate self-assembled monolayer sensor chips. Different fluids, with and without biomolecular components, were investigated. The pH-dependent surface interactions of two bio-inspired cationic peptides, AS8 and ES9, which are similar to an extracellular domain of the chitin synthase involved in mollusc shell formation, were also investigated in a biological buffer system. A range of experimental conditions are described that are suitable to study non-covalent molecular interactions in the presence of ionic substances, such as, mineral precursors below the solubility equilibrium. The peptide ES9, equal to the mollusc chitin synthase epitope, is less sensitive to changes in pH than its counterpart AS8 with a penta-lysine core, which lacks the flanking acidic residues. This study demonstrates the extraordinary potential of microfluidic surface acoustic wave biosensors to significantly expand our experimental capabilities for studying the principles underlying biomineralization in vitro. PMID:25383294

  15. TGfU--Would You Know It if You Saw It? Benchmarks from the Tacit Knowledge of the Founders

    ERIC Educational Resources Information Center

    Butler, Joy

    2014-01-01

    This paper explores the tacit expert knowledge and understanding about games curriculum and pedagogy of three men, Len Almond, David Bunker, and Rod Thorpe, credited as the founders of the Teaching Games for Understanding (TGfU) model. The model emerged from teacher practice in the late 1970s and was little theorized at the time, apart from a

  16. Non-Destructive Detection of Rebar Buried in a Reinforced Concrete Wall with Wireless Passive SAW Sensor

    NASA Astrophysics Data System (ADS)

    Fan, Yanping; Ji, Xiaojun; Cai, Ping; Lu, Qianhui

    2013-01-01

    In order to reduce the damage to the old reinforced concrete walls and work out the best construction scheme during the renovation of old buildings, it is often required to detect the position of rebar buried in concrete walls. In this paper, we propose a non-destructive method to detect the buried rebar by self-inductive sensor combined with surface acoustic wave resonator (SAWR). The proposed method has the advantages of wireless, passive and convenient operations. In our new design, the sensing element of self-inductance coil was made as a component of SAWR matching network. The distribution of rebar could be measured according to the system resonant frequency, using a signal demodulation device set. The depth of buried rebar and the deviation of output resonant frequency from inherent frequency of SAWR have an inverse relation. Finally, the validity of the method was verified in theoretical calculation and simulation.

  17. A see-saw of pre-Columbian boom regions in southern Peru, determined by large-scale circulation changes

    NASA Astrophysics Data System (ADS)

    Mchtle, B.; Schittek, K.; Forbriger, M.; Schbitz, F.; Eitel, B.

    2012-04-01

    Environmental changes and cultural transitions during several periods of Peruvian history show a strong coincidence between humid and dry climatic oscillations and the rise and decline of cultures. It is noteworthy, that alternating periods of geo-ecological fragility and stability occurred in time and space between the coastal Nasca region (14.5 S) and the high Andean northern Titicaca basin, just a few hundred kilometers to the east. Based on a multi-proxy palynological and sedimentological approach to reconstruct palaeoenvironmental changes, we found that the Nasca region received a maximum of precipitation during the archaeological boom times of the Early Horizon and the Early Intermediate Period (800 BC - 650 AD, Paracas and Nasca cultures) as well as during the late intermediate period (1150-1450 AD), whereas, in contrast, the Titicaca region further to the south-east experienced drought and cultural depression during that times. During the Middle Horizon (650 - 1150 AD), the Tiwanaku agronomy and culture boomed in the Titicaca region and expanded to the west, contemporaneous with a raised lake level and more humid conditions. In the Nasca region, runoff for irrigation purposes was reduced and less reliable due to drought. Considering a coincidence between environmental and cultural changes, we state that success and decline of civilizations were controlled by hydrological oscillations, triggering fertility as well as a critical loss of natural resources. In response to spatial changing resources, cultural foci were shifted. Therefore, the success of pre-Columbian civilizations was closely coupled to areas of geo-ecological favorability, which were directly controlled by distinct regional impacts of large-scale circulation mechanisms, including El Nio - Southern Oscillation (ENSO). Changes in the position of the intertropical convergence zone (ITCZ) and the Bolivian anticyclone determined meridional shifts in moisture transport across the Andes, which directly triggered human migration to the respective granaries.

  18. Defect detection of partially complete SAW and TIG welds using the ultrasonic time-of-flight diffraction method

    NASA Astrophysics Data System (ADS)

    Lawson, Shaun W.; Bonser, Gary R.

    1998-03-01

    An application of machine vision applied to the analysis of ultrasonic images formed using the time-of-flight diffraction (TOFD) method on incomplete weld geometries is described. The rationale of the work being to identify weld defects as soon as they are produced, thereby reducing the costs of any subsequent repairs. The analysis uses TOFD scans as input to a filtering and 'window' based variance operator for the segmentation of suspect defect areas inside the weld region. A suite of pc based software and a high temperature TOFD data acquisition system have been benchmarked through a series of demonstration trials on both 80mm thick carbon steel submerged arc welded testpieces, and 25mm thick carbon steel tungsten inert gas welded testpieces. The range of intentionally implanted defects, from root cracks to lack of side wall fusion, were detected with an overall accuracy of 79 percent on a data set of 174 defects on scans performed at 10-90 percent weld completion.

  19. 'See-saw' expression of microRNA-198 and FSTL1 from a single transcript in wound healing.

    PubMed

    Sundaram, Gopinath M; Common, John E A; Gopal, Felicia E; Srikanta, Satyanarayana; Lakshman, Krishnaswamy; Lunny, Declan P; Lim, Thiam C; Tanavde, Vivek; Lane, E Birgitte; Sampath, Prabha

    2013-03-01

    Post-transcriptional switches are flexible effectors of dynamic changes in gene expression. Here we report a new post-transcriptional switch that dictates the spatiotemporal and mutually exclusive expression of two alternative gene products from a single transcript. Expression of primate-specific exonic microRNA-198 (miR-198), located in the 3'-untranslated region of follistatin-like 1 (FSTL1) messenger RNA, switches to expression of the linked open reading frame of FSTL1 upon wounding in a human ex vivo organ culture system. We show that binding of a KH-type splicing regulatory protein (KSRP, also known as KHSRP) to the primary transcript determines the fate of the transcript and is essential for the processing of miR-198: transforming growth factor-? signalling switches off miR-198 expression by downregulating KSRP, and promotes FSTL1 protein expression. We also show that FSTL1 expression promotes keratinocyte migration, whereas miR-198 expression has the opposite effect by targeting and inhibiting DIAPH1, PLAU and LAMC2. A clear inverse correlation between the expression pattern of FSTL1 (pro-migratory) and miR-198 (anti-migratory) highlights the importance of this regulatory switch in controlling context-specific gene expression to orchestrate wound re-epithelialization. The deleterious effect of failure of this switch is apparent in non-healing chronic diabetic ulcers, in which expression of miR-198 persists, FSTL1 is absent, and keratinocyte migration, re-epithelialization and wound healing all fail to occur. PMID:23395958

  20. TGfU--Would You Know It if You Saw It? Benchmarks from the Tacit Knowledge of the Founders

    ERIC Educational Resources Information Center

    Butler, Joy

    2014-01-01

    This paper explores the tacit expert knowledge and understanding about games curriculum and pedagogy of three men, Len Almond, David Bunker, and Rod Thorpe, credited as the founders of the Teaching Games for Understanding (TGfU) model. The model emerged from teacher practice in the late 1970s and was little theorized at the time, apart from a…