Science.gov

Sample records for non-intrusive characterization methods

  1. Non-Intrusive Optical Diagnostic Methods for Flowfield Characterization

    NASA Technical Reports Server (NTRS)

    Tabibi, Bagher M.; Terrell, Charles A.; Spraggins, Darrell; Lee, Ja. H.; Weinstein, Leonard M.

    1997-01-01

    Non-intrusive optical diagnostic techniques such as Electron Beam Fluorescence (EBF), Laser-Induced Fluorescence (LIF), and Focusing Schlieren (FS) have been setup for high-speed flow characterization and large flowfield visualization, respectively. Fluorescence emission from the First Negative band of N2(+) with the (0,0) vibration transition (at lambda =391.44 nm) was obtained using the EBF technique and a quenching rate of N2(+)* molecules by argon gas was reported. A very high sensitivity FS system was built and applied in the High-Speed Flow Generator (HFG) at NASA LaRC. A LIF system is available at the Advanced Propulsion Laboratory (APL) on campus and a plume exhaust velocity measurement, measuring the Doppler shift from lambda = 728.7 nm of argon gas, is under way.

  2. Characterization of mixed waste for sorting and inspection using non-intrusive methods

    SciTech Connect

    Roberson, G.P.; Ryon, R.W.; Bull, N.L.

    1994-12-01

    Characterization of mixed wastes (that is, radioactive and otherwise hazardous) requires that all hazardous, non-conforming, and radioactive materials be identified, localized, and quantified. With such information, decisions can be made regarding whether the item is treatable or has been adequately treated. Much of the required information can be gained without taking representative samples and analyzing them in a chemistry laboratory. Non-intrusive methods can be used to provide this information on-line at the waste treatment facility. Ideally, the characterization would be done robotically, and either automatically or semi-automatically in order to improve efficiency and safety. For the FY94 Mixed Waste Operations (MWO) project, a treatable waste item is defined as a homogeneous metal object that has external radioactive or heavy metal hazardous contamination. Surface treatment of some kind would therefore be the treatment method to be investigated. The authors developed sorting and inspection requirements, and assessed viable non-intrusive techniques to meet these requirements. They selected radiography, computed tomography and X-ray fluorescence. They have characterized selected mock waste items, and determined minimum detectable amounts of materials. They have demonstrated the efficiency possible by integrating radiographic with tomographic data. Here, they developed a technique to only use radiographic data where the material is homogeneous (fast), and then switching to tomography in those areas where heterogeneity is detected (slower). They also developed a tomographic technique to quantify the volume of each component of a mixed material. This is useful for such things as determining ash content. Lastly, they have developed a document in MOSAIC, an Internet multi-media browser. This document is used to demonstrate the ability to share data and information world-wide.

  3. Integrating Intrusive and Non-intrusive Characterization Methods To Achieve A Conceptual Site Model For The SLDA FUSRAP

    SciTech Connect

    Durham, L.A.; Peterson, J.M.; Frothingham, D.G.; Frederick, W.T.; Lenart, W.

    2008-07-01

    The U.S. Army Corps of Engineers (USACE) is addressing radiological contamination following Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) requirements at the Shallow Land Disposal Area (SLDA) site, which is a radiologically contaminated property that is part of the Formerly Utilized Sites Remedial Action Program (FUSRAP). The SLDA is an 18-hectare (44- acre) site in Parks Township, Armstrong County, Pennsylvania, about 37 kilometers (23 miles) east-northeast of Pittsburgh. According to historical record, radioactive wastes were disposed of at the SLDA in a series of trenches by the Nuclear Materials and Equipment Company (NUMEC) in the 1960's. The wastes originated from the nearby Apollo nuclear fuel fabrication facility, which began operations under NUMEC in the late 1950's and fabricated enriched uranium into naval reactor fuel elements. It is believed that the waste materials were buried in a series of pits constructed adjacent to one another in accordance with an Atomic Energy Commission (AEC) regulation that has since been rescinded. A CERCLA remedial investigation/feasibility study (RI/FS) process was completed for the SLDA site, and the results of the human health risk assessment indicated that the radiologically contaminated wastes could pose a risk to human health in the future. There are no historical records that provide the exact location of these pits. However, based on geophysical survey results conducted in the 1980's, these pits were defined by geophysical anomalies and were depicted on historical site drawings as trenches. At the SLDA site, a combination of investigative methods and tools was used in the RI/FS and site characterization activities. The SLDA site provides an excellent example of how historical documents and data, historical aerial photo analysis, physical sampling, and non-intrusive geophysical and gamma walkover surveys were used in combination to reduce the uncertainty in the location of the

  4. Non-Intrusive Pressure/Multipurpose Sensor and Method

    NASA Technical Reports Server (NTRS)

    Smith, William C. (Inventor)

    2001-01-01

    Method and apparatus are provided for determining pressure using a non-intrusive sensor that is easily attachable to the plumbing of a pressurized system. A bent mode implementation and a hoop mode implementation of the invention are disclosed. Each of these implementations is able to nonintrusively measure pressure while fluid is flowing. As well, each implementation may be used to measure mass flow rate simultaneously with pressure. An ultra low noise control system is provided for making pressure measurements during gas flow. The control system includes two tunable digital bandpass filters with center frequencies that are responsive to a clock frequency. The clock frequency is divided by a factor of N to produce a driving vibrational signal for resonating a metal sensor section.

  5. Non-intrusive method of measuring PCV blowby constituents

    SciTech Connect

    Crane, M.E.; Ariga, S.; Boulard, R.; Lindamood, B.

    1994-10-01

    A technique is presented that has been successfully demonstrated to non-intrusively and quickly sample gases typically found in PCV systems. Color Detection Tubes (CDTs) were used with a simple sampling arrangement to monitor CO{sub 2}, NO{sub x}, O{sub 2}, and H{sub 2}O(g) at the closure line, crankcase, and PCV line. Measurements were accurate and could be made instantaneously. Short Path Thermal Desorbtion Tubes (SPTDTs) were used at the same engine locations for the characterization of fuel- and oil-derived hydrocarbon (HC) fractions and required only 50 cc samples. High engine loads caused pushover of blowby vapors as indicated by increased concentrations of CO{sub 2}, NO{sub x}, H{sub 2}O(g), and fuel HCs in the engines` fresh air inlets during WOT operation. Peak concentrations of blowby vapors were measured in the crankcase under no load and part throttle conditions. Oxygen concentrations always opposed the trends of CO{sub 2}, NO{sub x}, and H{sub 2}O(g). SPTDT data revealed that the PCV system consumes approximately 100-200 times more fuel vapors than oil vapors, on a mass basis; however, PCV-derived oil consumption represented almost 12 percent of total engine oil consumption under no load conditions. 8 refs., 17 figs.

  6. Non-intrusive measurement and hydrodynamics characterization of gas-solid fluidized beds: a review

    NASA Astrophysics Data System (ADS)

    Sun, Jingyuan; Yan, Yong

    2016-11-01

    Gas-solid fluidization is a well-established technique to suspend or transport particles and has been applied in a variety of industrial processes. Nevertheless, our knowledge of fluidization hydrodynamics is still limited for the design, scale-up and operation optimization of fluidized bed reactors. It is, therefore, essential to characterize the two-phase flow behaviours in gas-solid fluidized beds and monitor the fluidization processes for control and optimization. A range of non-intrusive techniques have been developed or proposed for measuring the fluidization dynamic parameters and monitoring the flow status without disturbing or distorting the flow fields. This paper presents a comprehensive review of the non-intrusive measurement techniques and the current state of knowledge and experience in the characterization and monitoring of gas-solid fluidized beds. These techniques are classified into six main categories as per sensing principles, electrostatic, acoustic emission and vibration, visualization, particle tracking, laser Doppler anemometry and phase Doppler anemometry as well as pressure-fluctuation methods. Trends and future developments in this field are also discussed.

  7. A Non-Intrusive Method for Monitoring the Degradation of MOSFETs

    PubMed Central

    Wu, Li-Feng; Zheng, Yu; Guan, Yong; Wang, Guo-Hui; Li, Xiao-Juan

    2014-01-01

    Highly reliable embedded systems have been widely applied in the fields of aerospace, nuclear power, high-speed rail, etc., which are related to security and economic development. The reliability of the power supply directly influences the security of the embedded system, and has been the research focus of numerous electronic information and energy studies. The degradation of power modules occupies a dominant position among the key factors affecting the power supply reliability. How to dynamically determine the degradation state and forecast the remaining useful life of working power modules is critical. Therefore, an online non-intrusive method of obtaining the degradation state of MOSFETs based on the Volterra series is proposed. It uses the self-driving signal of MOSFETs as a non-intrusive incentive, and extracts the degradation characteristics of MOSFETs by the frequency-domain kernel of the Volterra series. Experimental results show that the identification achieved by the method agrees well with the theoretical analysis. PMID:24434873

  8. Research on optical fiber flow test method with non-intrusion

    NASA Astrophysics Data System (ADS)

    Shang, Ying; Liu, Xiaohui; Wang, Chang; Zhao, Wenan

    2014-06-01

    In the field of oil well logging, real-time monitoring of the fluid flow parameter provides a scientific basis for oil and gas optimization exploration and increase in reservoir recovery, so a non-intrusive flow test method based on turbulent vibration was proposed. The specific length of the sensor fiber wound tightly around the outer wall of the pipe was connected with the optical fiber gratings at both ends, and the sensor fiber and the optical fiber gratings composed the flow sensing unit. The dynamic pressure was generated by the turbulence when fluid flows through the pipe, and the dynamic pressure resulted in the light phase shift of the sensor fiber. The phase information was demodulated by the fiber optic interferometer technology, time division multiplexing technology, and phase generated carrier modulation and demodulation techniques. The quadratic curve relationship between the phase change and flow rate was found by experimental data analysis, and the experiment confirmed the feasibility of the optical fiber flow test method with non-intrusion and achieved the real-time monitoring of the fluid flow.

  9. A non-intrusive method for temperature measurements in flames produced by milligram-sized solid samples

    NASA Astrophysics Data System (ADS)

    Frances, Colleen Elizabeth

    Fires are responsible for the loss of thousands of lives and billions of dollars in property damage each year in the United States. Flame retardants can assist in the prevention of fires through mechanisms which either prevent or greatly inhibit flame spread and development. In this study samples of both brominated and non-brominated polystyrene were tested in the Milligram-scale Flaming Calorimeter and images captured with two DSL-R cameras were analyzed to determine flame temperatures through use of a non-intrusive method. Based on the flame temperature measurement results, a better understanding of the gas phase mechanisms of flame retardants may result, as temperature is an important diagnostic in the study of fire and combustion. Measurements taken at 70% of the total flame height resulted in average maximum temperatures of about 1656 K for polystyrene and about 1614 K for brominated polystyrene, suggesting that the polymer flame retardant may reduce flame temperatures.

  10. A proposed non-intrusive method for finding coefficients of slip and molecular reflectivity in microgravity

    NASA Technical Reports Server (NTRS)

    Noever, D. A.; Rosenberger, F. E.

    1989-01-01

    A proposed experimental program to look at a series of vapor transport properties measured along solid and liquid surfaces is described. The research objectives proposed are: (1) with accuracy otherwise unobtainable on ground, to determine the coefficient of slip measured between gases and the surfaces of liquids and solids; (2) for the first time, to classify and tabulate dominant surface effects found for a variety of solids, particularly those crystalized by vapor transport; and (3) to extend understanding of settling rates predicted for cosmic dust and condensed vapor falling through planetary atmospheres. The method used to obtain these objectives, has aided, to an order of magnitude, understanding of various liquid-gas interfaces such as oil and water. But to date, no similar characterization has proved successful for solids or liquids of uncertain densities. Likewise, no data exist in either ground-based research or as part of a microgravity program that, when collected with the high accuracy expected in low gravity, could definitely settle outstanding questions in kinetic theory, molecular dynamics, and cosmic physics.

  11. Method for Non-Intrusively Identifying a Contained Material Utilizing Uncollided Nuclear Transmission Measurements

    SciTech Connect

    Morrison, John L.; Stephens, Alan G.; Grover Blaine S.

    1999-02-26

    An improved nuclear diagnostic method identifies a contained target material by measuring on-axis, mono-energetic uncollided particle radiation transmitted through a target material for two penetrating radiation beam energies, and applying specially developed algorithms to estimate a ratio of macroscopic neutron cross-sections for the uncollided particle radiation at the two energies, where the penetrating radiation is a neutron beam, or a ratio of linear attenuation coefficients for the uncollided particle radiation at the two energies, where the penetrating radiation is a gamma-ray beam. Alternatively, the measurements are used to derive a minimization formula based on the macroscopic neutron cross-sections for the uncollided particle radiation at the two neutron beam energies, or the linear attenuation coefficients for the uncollided particle radiation at the two gamma-ray beam energies. A candidate target material database, including known macroscopic neutron cross-sections or linear attenuation coefficients for target materials at the selected neutron or gamma-ray beam energies, is used to approximate the estimated ratio or to solve the minimization formula, such that the identity of the contained target material is discovered.

  12. Method for non-intrusively identifying a contained material utilizing uncollided nuclear transmission measurements

    DOEpatents

    Morrison, John L.; Stephens, Alan G.; Grover, S. Blaine

    2001-11-20

    An improved nuclear diagnostic method identifies a contained target material by measuring on-axis, mono-energetic uncollided particle radiation transmitted through a target material for two penetrating radiation beam energies, and applying specially developed algorithms to estimate a ratio of macroscopic neutron cross-sections for the uncollided particle radiation at the two energies, where the penetrating radiation is a neutron beam, or a ratio of linear attenuation coefficients for the uncollided particle radiation at the two energies, where the penetrating radiation is a gamma-ray beam. Alternatively, the measurements are used to derive a minimization formula based on the macroscopic neutron cross-sections for the uncollided particle radiation at the two neutron beam energies, or the linear attenuation coefficients for the uncollided particle radiation at the two gamma-ray beam energies. A candidate target material database, including known macroscopic neutron cross-sections or linear attenuation coefficients for target materials at the selected neutron or gamma-ray beam energies, is used to approximate the estimated ratio or to solve the minimization formula, such that the identity of the contained target material is discovered.

  13. Non-intrusive hydro-geophysical characterization of the unsaturated zone of South India-A case study

    NASA Astrophysics Data System (ADS)

    Arora, Tanvi; Boisson, Alexandre; Ahmed, Shakeel

    2016-10-01

    The unsaturated zone is the gateway for water movement from the land surface to the saturated zone. The amount of recharge to aquifer, related to the percolation, is constrained by the characteristics of the unsaturated zone. Unsaturated zone research is still needed to understand the flow paths of the recharge through it, particularly in heterogeneous media. One possibility for this understanding is to use time lapse electrical resistivity tomography [TLERT]. However, the relationship between moisture and electrical resistivity changes still need to be investigated. A time lapse electrical resistivity tomography experiment was carried out in the unsaturated zone of granitic terrain at National Geophysical Research Institute, Hyderabad to develop a relationship between soil moisture and electrical resistivity changes. The measurements of soil moisture using neutron probe and resistivity from TLERT images were correlated. To extend the spatial information between point measurements using neutron probe, a variographic analysis was performed. Variograms were computed using MS-EXCEL to ensure a desired number of pairs for a variogram. The two different datasets (resistivity and moisture) were amalgamated on a common platform by geostatistical tools to relate the soil moisture and resistivity. A relation is established between moisture variations in the form of saturation versus the resistivity. This relation has been tested both from an experiment in laboratory and in field. It shows that initially a non-linear relation exist between soil moisture and resistivity. However, the resistivity becomes invariant even with the moisture increase in the range of 11%-13%. Recharge is reflected in resistivity images by a decrease, along the preferred permeable zones. Since the unsaturated zone exhibit extremely high variability, both in space and time, the surface geophysical investigations such as TLERT (Time Lapse Electrical Resistivity Tomography) is a useful method to

  14. Non-intrusive refrigerant charge indicator

    DOEpatents

    Mei, Viung C.; Chen, Fang C.; Kweller, Esher

    2005-03-22

    A non-intrusive refrigerant charge level indicator includes a structure for measuring at least one temperature at an outside surface of a two-phase refrigerant line section. The measured temperature can be used to determine the refrigerant charge status of an HVAC system, and can be converted to a pressure of the refrigerant in the line section and compared to a recommended pressure range to determine whether the system is under-charged, properly charged or over-charged. A non-intrusive method for assessing the refrigerant charge level in a system containing a refrigerant fluid includes the step of measuring a temperature at least one outside surface of a two-phase region of a refrigerant containing refrigerant line, wherein the temperature measured can be converted to a refrigerant pressure within the line section.

  15. TTP AL921102: An integrated geophysics program for non-intrusive characterization of mixed-Waste landfill sites. Final report

    SciTech Connect

    Hasbrouck, J.C.

    1993-09-01

    This Technical Task conducted for the US Department of Energy Office of Technology Development demonstrates the effectiveness of integrating several surface geophysical techniques to nonintrusively characterize mixed-waste landfill sites. An integrated approach enables an area to be characterized faster and cheaper because repeated access is not necessary and offers data and interpretations not attainable by a single technique. Field demonstrations using the complex galvanic resistivity, spontaneous potential (SP), ground-penetrating radar (GPR), time-domain electromagnetic (TDEM), shear-wave (S-wave) seismic and compressional-wave (P-wave) seismic geophysical techniques were conducted at the Mixed-Waste Landfill Integrated Demonstration (MWLID) test site at the Sandia National Laboratories/New Mexico in Albuquerque. Data were acquired in two areas that have both known and unknown attributes. Although data from numerous profiles were analyzed, three lines were chosen as representative of the landfill site: Line 20E that crosses both the known Chromic Acid and Organics Pits, Line 60E that transectes an essentially barren area, and Line 125E located in an area with unknown subsurface conditions.

  16. Transient Torque Method: A Fast and Non-Intrusive Technique to Simultaneously Determine Viscosity and Electrical Conductivity of Semiconducting and Metallic Melts

    NASA Technical Reports Server (NTRS)

    Li, C.; Ban, H.; Lin, B.; Scripa, R. N.; Su, C.; Lehoczky, S. L.; Zhu, S.

    2003-01-01

    A transient torque method was developed to rapidly and simultaneously determine the viscosity and electrical conductivity of semiconducting or metallic melts. The experimental setup is similar to that for the oscillation cup technique. The melt sample is sealed inside a fused silica ampoule, and the ampoule is suspended by a long quartz fiber to form a torsional oscillation system. A rotating magnetic field is used to induce a rotating flow in the conductive melt, which causes the ampoule to rotate along its axis. A sensitive angular detector is used to measure the deflection angle of the ampoule. Based on the transient behavior of the deflection angle as the rotating magnetic field is applied, the electrical conductivity and viscosity of the melt can be obtained simultaneously by numerically fitting the data to a set of governing equations. The transient torque viscometer was applied successfully to measure the viscosity and electrical conductivity of high purity mercury at 53.4 C. The results were in excellent agreement with the published data. The main advantage of the technique is that the measurement can be completed in one or two minutes, as opposed to the one or two-hour measurement time required by the oscillation cup technique. The method is non-intrusive; capable of rapid measurement of the viscosity of toxic, high vapor pressure melts at elevated temperatures. In addition, the transient torque viscometer can also be operated as an oscillation cup viscometer if desired.

  17. A Novel Non-Intrusive Method to Resolve the Thermal-Dome-Effect of Pyranometers: Radiometric Calibration and Implications

    NASA Technical Reports Server (NTRS)

    Ji, Qiang; Tsay, Si-Chee; Lau, K. M.; Hansell, R. A.; Butler, J. J.; Cooper, J. W.

    2011-01-01

    Traditionally the calibration equation for pyranometers assumes that the measured solar irradiance is solely proportional to the thermopile's output voltage; therefore only a single calibration factor is derived. This causes additional measurement uncertainties because it does not capture sufficient information to correctly account for a pyranometer's thermal effect. In our updated calibration equation, temperatures from the pyranometer's dome and case are incorporated to describe the instrument's thermal behavior, and a new set of calibration constants are determined, thereby reducing measurement uncertainties. In this paper, we demonstrate why a pyranometer's uncertainty using the traditional calibration equation is always larger than a-few-percent, but with the new approach can become much less than 1% after the thermal issue is resolved. The highlighted calibration results are based on NIST-traceable light sources under controlled laboratory conditions. The significance of the new approach lends itself to not only avoiding the uncertainty caused by a pyranometer's thermal effect but also the opportunity to better isolate and characterize other instrumental artifacts, such as angular response and non-linearity of the thermopile, to further reduce additional uncertainties. We also discuss some of the implications, including an example of how the thermal issue can potentially impact climate studies by evaluating aerosol's direct-radiative effect using field measurements with and without considering the pyranometer's thermal effect. The results of radiative transfer model simulation show that a pyranometer's thermal effect on solar irradiance measurements at the surface can be translated into a significant alteration of the calculated distribution of solar energy inside the column atmosphere.

  18. Non-intrusive speed sensor

    NASA Technical Reports Server (NTRS)

    Wyett, L.

    1986-01-01

    In Phase I of the Non-Intrusive Speed Sensor program, a computerized literature search was performed to identify candidate technologies for remote, non-intrusive speed sensing applications in Space Shuttle Main Engine (SSME) turbopumps. The three most promising technologies were subjected to experimental evaluation to quantify their performance characteristics under the harsh environmental requirements within the turbopumps. Although the infrared and microwave approaches demonstrated excellent cavitation immunity in laboratory tests, the variable-source magnetic speed sensor emerged as the most viable approach. Preliminary design of this speed sensor encountered no technical obstacles and resulted in viable and feasible speed nut, sensor housing, and sensor coil designs. Phase II of this program developed the variable-source magnetic speed sensor through the detailed design task and guided the design into breadboard fabrication. The speed sensor and its integral speed nut were evaluated at both unit and system level testing. The final room-temperature and cryogenic spin testing of the hardware demonstrated that the sensor was capable of generating sufficient output signal to enable remote speed sensing from 1500 to 40000 rpm over a speed nut/sensor separation of 3.5 inches.

  19. Nuclear data needs for non-intrusive inspection.

    SciTech Connect

    Smith, D. L.; Michlich, B. J.

    2000-11-29

    Various nuclear-based techniques are being explored for use in non-intrusive inspection. Their development is motivated by the need to prevent the proliferation of nuclear weapons, to thwart trafficking in illicit narcotics, to stop the transport of explosives by terrorist organizations, to characterize nuclear waste, and to deal with various other societal concerns. Non-intrusive methods are sought in order to optimize inspection speed, to minimize damage to packages and containers, to satisfy environmental, health and safety requirements, to adhere to legal requirements, and to avoid inconveniencing the innocent. These inspection techniques can be grouped into two major categories: active and passive. They almost always require the use of highly penetrating radiation and therefore are generally limited to neutrons and gamma rays. Although x-rays are widely employed for these purposes, their use does not constitute nuclear technology and therefore is not discussed here. This paper examines briefly the basic concepts associated with nuclear inspection and investigates the related nuclear data needs. These needs are illustrated by considering four of the methods currently being developed and tested.

  20. Non-Intrusive Grammar in Writing.

    ERIC Educational Resources Information Center

    Roberts, Claudette M.; Boggase, Barbara A.

    Since introducing a grammar unit can be daunting and frustrating for both teachers and students, a collaborative unit for a 10th-grade class was planned that would satisfy an administrative requirement but also maintain the integrity of the writing program. The unit was planned by developing an approach of non-intrusive grammar instruction at the…

  1. Non-intrusive cooling system

    DOEpatents

    Morrison, Edward F.; Bergman, John W.

    2001-05-22

    A readily replaceable heat exchange cooling jacket for applying fluid to a system conduit pipe. The cooling jacket comprises at least two members, separable into upper and lower portions. A chamber is formed between the conduit pipe and cooling jacket once the members are positioned about the pipe. The upper portion includes a fluid spray means positioned above the pipe and the bottom portion includes a fluid removal means. The heat exchange cooling jacket is adaptable with a drain tank, a heat exchanger, a pump and other standard equipment to provide a system for removing heat from a pipe. A method to remove heat from a pipe, includes the steps of enclosing a portion of the pipe with a jacket to form a chamber between an outside surface of the pipe and the cooling jacket; spraying cooling fluid at low pressure from an upper portion of the cooling jacket, allowing the fluid to flow downwardly by gravity along the surface of the pipe toward a bottom portion of the chamber; and removing the fluid at the bottom portion of the chamber.

  2. Non-intrusive appliance monitor apparatus

    DOEpatents

    Hart, George W.; Kern, Jr., Edward C.; Schweppe, Fred C.

    1989-08-15

    A non-intrusive monitor of energy consumption of residential appliances is described in which sensors, coupled to the power circuits entering a residence, supply analog voltage and current signals which are converted to digital format and processed to detect changes in certain residential load parameters, i.e., admittance. Cluster analysis techniques are employed to group change measurements into certain categories, and logic is applied to identify individual appliances and the energy consumed by each.

  3. Non-intrusive appliance monitor apparatus

    DOEpatents

    Hart, G.W.; Kern, E.C. Jr.; Schweppe, F.C.

    1989-08-15

    A non-intrusive monitor of energy consumption of residential appliances is described in which sensors, coupled to the power circuits entering a residence, supply analog voltage and current signals which are converted to digital format and processed to detect changes in certain residential load parameters, i.e., admittance. Cluster analysis techniques are employed to group change measurements into certain categories, and logic is applied to identify individual appliances and the energy consumed by each. 9 figs.

  4. Non-intrusive electric field sensing

    NASA Astrophysics Data System (ADS)

    Schultz, S. M.; Selfridge, R.; Chadderdon, S.; Perry, D.; Stan, N.

    2014-04-01

    This paper presents an overview of non-intrusive electric field sensing. The non-intrusive nature is attained by creating a sensor that is entirely dielectric, has a small cross-sectional area, and has the interrogation electronics a long distance away from the system under test. One non-intrusive electric field sensing technology is the slab coupled optical fiber sensor (SCOS). The SCOS consists of an electro-optic crystal attached to the surface of a D-shaped optical fiber. It is entirely dielectric and has a cross-sectional area down to 0.3mm by 0.3mm. The SCOS device functions as an electric field sensor through use of resonant mode coupling between the crystal waveguide and the core of a D-shaped optical fiber. The resonant mode coupling of a SCOS device occurs at specific wavelengths whose spectral locations are determined in part by the effective refractive index of the modes in the slab. An electric field changes the refractive index of the slab causing a shift in the spectral position of the resonant modes. This paper describes an overview of the SCOS technology including the theory, fabrication, and operation. The effect of crystal orientation and crystal type are explained with respect to directional sensitivity and frequency response.

  5. INEL cold test pit demonstration of improvements in information derived from non-intrusive geophysical methods over buried waste sites. Phase 1, Final report

    SciTech Connect

    Not Available

    1993-09-08

    The objectives of this research project were to lay the foundation for further improvement in the use of geophysical methods for detection of buried wastes, and to increase the information content derived from surveys. Also, an important goal was to move from mere detection to characterization of buried wastes. The technical approach to achieve these objectives consisted of: (1) Collect a data set of high spatial density; (2) Acquire data with multiple sensors and integrate the interpretations inferred from the various sensors; (3) Test a simplified time domain electromagnetic system; and (4) Develop imaging and display formats of geophysical data readily understood by environmental scientists and engineers. The breadth of application of this work is far reaching. Not only are uncontrolled waste pits and trenches, abandoned underground storage tanks, and pipelines found throughout most US DOE facilities, but also at military installations and industrial facilities. Moreover, controlled land disposal sites may contain ``hot spots`` where drums and hazardous material may have been buried. The technologies addressed by the R&D will benefit all of these activities.

  6. INEL cold test pit demonstration of improvements in information derived from non-intrusive geophysical methods over buried waste sites. Phase 2, Final report

    SciTech Connect

    Not Available

    1994-04-29

    Under Contract between US DOE Idaho National Engineering Laboratory (INEL) and the Blackhawk Geosciences Division of Coleman Research Corporation (BGD-CRC), geophysical investigations were conducted to improve the detection of buried wastes. Site characterization is a costly and time consuming process with the most costly components being drilling, sampling, and chemical analysis of samples. There is a focused effort at US DOE and other agencies to investigate methodologies that reduce costs and shorten the time between characterization and clean-up. These methodologies take the form of employing non-invasive (geophysical) and minimal invasive (e.g., cone penetrometer driving) techniques of characterization, and implementing a near real-time, rational decision-making process (Expedited Site Characterization). Over the Cold Test Pit (CTP) at INEL, data were acquired with multiple sensors on a dense grid. Over the CTP the interpretations inferred from geophysical data are compared with the known placement of various waste forms in the pit. The geophysical sensors employed were magnetics, frequency and time domain electromagnetics, and ground penetrating radar. Also, because of the high data density acquired, filtering and other data processing and imaging techniques were tested. The conclusions derived from the geophysical surveys were that pit boundaries, berms between cells within the pit, and individual objects placed in the pit were best mapped by the new Geonics EM61 time domain EM metal detector. Part of the reason for the effectiveness of the time domain metal detector is that objects buried in the pit are dominantly metallic. Also, the utility of geophysical data is significantly enhanced by dimensional and 3-dimensional imaging formats. These images will particularly assist remediation engineers in visualizing buried wastes.

  7. Non-Intrusive, Distributed Gas Sensing Technology for Advanced Spacesuits

    NASA Technical Reports Server (NTRS)

    Delgado, Jesus; Phillips, Straun; Rubtsov, Vladimir; Chullen, Cinda

    2015-01-01

    Chemical sensors for monitoring gas composition, including oxygen, humidity, carbon dioxide, and trace contaminants, are needed to characterize and validate spacesuit design and operating parameters. This paper reports on the first prototypes of a non-intrusive gas sensing technology based on flexible sensitive patches positioned inside spacesuit prototypes and interrogated via optical fibers routed outside the suit, taking advantage of the transparent materials of the suit prototypes. The sensitive patches are based on luminescent materials whose emission parameters vary with the partial pressure of a specific gas. Patches sensitive to carbon dioxide, humidity, and temperature have been developed, and their preliminary laboratory characterization in Mark III-like helmet parts is described. The first prototype system consists of a four-channel fiber optic luminescent detector that can be used to monitor any of the selected target gases at four locations. To switch from one gas to another we replace the (disposable) sensor patches and adjust the system settings. Repeatability among sensitive patches and of sensor performance from location to location has been confirmed, assuring that suit engineers will have flexibility in selecting multiple sensing points, fitting the sensor elements into the spacesuit, and easily repositioning the sensor elements as desired. The evaluation of the first prototype for monitoring carbon dioxide during washout studies in a spacesuit prototype is presented.

  8. Non-Intrusive, Distributed Gas Sensing Technology for Advanced Spacesuits

    NASA Technical Reports Server (NTRS)

    Delgado, Jesus; Phillips, Straun; Rubtsov, Vladimir; Chullen, Cinda

    2015-01-01

    Chemical sensors for monitoring gas composition, including oxygen, humidity, carbon dioxide, and trace contaminants are needed to characterize and validate spacesuit design and operating parameters. This paper reports on the first prototypes of a non-intrusive gas sensing technology based on flexible sensitive patches positioned inside spacesuit prototypes and interrogated by optical fibers routed outside the suit, taking advantage of the transparent materials of the suit prototypes. The sensitive patches are based on luminescent materials whose emission parameters vary with the partial pressure of a specific gas. Patches sensitive to carbon dioxide, humidity, oxygen, and ammonia have been developed, and their preliminary characterization in the laboratory using Mark III-like helmet parts is described. The first prototype system consists of a four-channel fiber optic luminescent detector that can be used to monitor any of the selected target gases at four locations. To switch from one gas to another we replace the (disposable) sensor patches and adjust the system settings. Repeatability among sensitive patches and of sensor performance from location to location has been confirmed, assuring that suit engineers will have flexibility in selecting multiple sensing points, fitting the sensor elements into the spacesuit, and easily repositioning the sensor elements as desired. The evaluation of the first prototype for monitoring carbon dioxide during washout studies in a space suit prototype is presented.

  9. Non-intrusive measurements in a rocket engine combustor

    NASA Astrophysics Data System (ADS)

    Farhangi, S.; Gylys, V. T.; Jensen, R. J.

    1993-07-01

    In recent years analytical tools to characterize combustor flow have been developed in order to support design. To facilitate anchoring of combustion related physical models and the CFD codes in which they are incorporated, considerable development and application of non-intrusive combustion diagnostic capabilities has occurred. Raman spectroscopy can be used to simultaneously detect all polyatomic molecules present in significant concentrations and to determine gas temperature. This is because all molecules possess a distinct temperature dependent Raman spectrum. A multi-point diagnostic system for non-intrusive temperature and species profiling in rocket engines has been developed at Rocketdyne. In the present effort, the system has been undergoing validation for application to rocket engine component testing. A 4 inch diameter windowed combustor with a coaxial gas-gas injector was chosen for this series of validation experiments. Initially an excimer-pumped tunable dye laser and later a solid state Nd-Yag laser served as excitation sources. The Raman signal was dispersed by a monochromator and detected by a gated, intensified Charged Coupled Device (CCD) array. Experiments were carried out prior to each series of hot fire tests to ensure that the Raman signal detected was due to a spontaneous rather than a stimulated Raman emission process. Over sixty hot fire tests were conducted during the first series of tests with the excimer/dye laser. All hot fire testing was at a mixture ratio of 0.5 and chamber pressures of approximately 100 and approximately 300 psia. The Raman spectra of hydrogen, water vapor and oxygen recorded during single element hot fire tests were reduced and analyzed. A significant achievement was the attainment of single shot Raman spectra in cold flow tests. Unfortunately, the single shot signal-to-noise ratio deteriorated to an unacceptable level during the hot fire testing. Attempts to obtain temperature data from the hydrogen Q1-branch

  10. Non-intrusive measurements in a rocket engine combustor

    NASA Technical Reports Server (NTRS)

    Farhangi, S.; Gylys, V. T.; Jensen, R. J.

    1993-01-01

    In recent years analytical tools to characterize combustor flow have been developed in order to support design. To facilitate anchoring of combustion related physical models and the CFD codes in which they are incorporated, considerable development and application of non-intrusive combustion diagnostic capabilities has occurred. Raman spectroscopy can be used to simultaneously detect all polyatomic molecules present in significant concentrations and to determine gas temperature. This is because all molecules possess a distinct temperature dependent Raman spectrum. A multi-point diagnostic system for non-intrusive temperature and species profiling in rocket engines has been developed at Rocketdyne. In the present effort, the system has been undergoing validation for application to rocket engine component testing. A 4 inch diameter windowed combustor with a coaxial gas-gas injector was chosen for this series of validation experiments. Initially an excimer-pumped tunable dye laser and later a solid state Nd-Yag laser served as excitation sources. The Raman signal was dispersed by a monochromator and detected by a gated, intensified Charged Coupled Device (CCD) array. Experiments were carried out prior to each series of hot fire tests to ensure that the Raman signal detected was due to a spontaneous rather than a stimulated Raman emission process. Over sixty hot fire tests were conducted during the first series of tests with the excimer/dye laser. All hot fire testing was at a mixture ratio of 0.5 and chamber pressures of approximately 100 and approximately 300 psia. The Raman spectra of hydrogen, water vapor and oxygen recorded during single element hot fire tests were reduced and analyzed. A significant achievement was the attainment of single shot Raman spectra in cold flow tests. Unfortunately, the single shot signal-to-noise ratio deteriorated to an unacceptable level during the hot fire testing. Attempts to obtain temperature data from the hydrogen Q1-branch

  11. Active Learning Framework for Non-Intrusive Load Monitoring: Preprint

    SciTech Connect

    Jin, Xin

    2016-05-16

    Non-Intrusive Load Monitoring (NILM) is a set of techniques that estimate the electricity usage of individual appliances from power measurements taken at a limited number of locations in a building. One of the key challenges in NILM is having too much data without class labels yet being unable to label the data manually for cost or time constraints. This paper presents an active learning framework that helps existing NILM techniques to overcome this challenge. Active learning is an advanced machine learning method that interactively queries a user for the class label information. Unlike most existing NILM systems that heuristically request user inputs, the proposed method only needs minimally sufficient information from a user to build a compact and yet highly representative load signature library. Initial results indicate the proposed method can reduce the user inputs by up to 90% while still achieving similar disaggregation performance compared to a heuristic method. Thus, the proposed method can substantially reduce the burden on the user, improve the performance of a NILM system with limited user inputs, and overcome the key market barriers to the wide adoption of NILM technologies.

  12. Nuclear data for non-intrusive inspection systems

    SciTech Connect

    Bendahan, J.; Loveman, R.; Gozani, T.

    1994-12-31

    Non-intrusive inspection systems based on nuclear techniques utilize the interaction of neutrons and gamma rays to determine the elemental constituents of the inspected object. The Thermal Neutron Analysis System has been used to detect explosives and narcotics concealed in passenger luggage and small objects. More recently the Pulsed Fast Neutron Analysis technique is being used to detect contraband in large cargo containers and has been proposed for the characterization of waste drums. The design of these systems requires the utilization of simulation codes where the accuracy of the results depends largely on the nuclear libraries. Several nuclear data evaluations were reviewed and compared with existing data to identify the most accurate ones. Large discrepancies were found among the various nuclear libraries, mainly in the production cross sections and angular distributions of gamma rays, stimulated by neutron interactions. An experimental program was carried out to correct and complement the required data. Evaluations of gamma-ray production cross sections for carbon, oxygen and chlorine are reviewed and compared with existing and new experimental data.

  13. Non-intrusive measurement techniques for hydroelectric applicants

    SciTech Connect

    Birch, R.; Lemon, D.

    1995-12-31

    Non-intrusive acoustic methods for measuring flows, originally developed for oceanographic applications, are being used in and around hydroelectric dams. The acoustic methods can be categorized as either back-scattering or forward-scattering. The first, using the back-scattered signal, measures the Doppler shift of the returning echo to determine the along-beam component of flow. These instruments are generally called Acoustic Doppler Current Profilers (ADCP). Three beam solutions allow computation of the velocity components. Time gating the return provides a velocity profile with bin segments as small as 0.25 in. In areas of strong magnetic deviation, often the case beside large dams, a gyrocompass can be used to provide directional orientation. The velocity data can also be used to quickly compute river or channel discharge. Typical applications and several case studies are presented. The second acoustic technique is based on a forward-scattering phenomenon known as scintillation. This technique has been used on the Fraser River to monitor flows, and properties of the signal have recently been correlated with the biomass of upstream-migrating salmon. Acoustic scintillation flow measurements are well suited to applications with limited space in the along-flow direction. Applications to hydroelectric dams include turbine intake flow measurements, and a system has been developed to measure flow along fish diversion screens.

  14. Non-intrusive practitioner pupil detection for unmodified microscope oculars.

    PubMed

    Fuhl, Wolfgang; Santini, Thiago; Reichert, Carsten; Claus, Daniel; Herkommer, Alois; Bahmani, Hamed; Rifai, Katharina; Wahl, Siegfried; Kasneci, Enkelejda

    2016-12-01

    Modern microsurgery is a long and complex task requiring the surgeon to handle multiple microscope controls while performing the surgery. Eye tracking provides an additional means of interaction for the surgeon that could be used to alleviate this situation, diminishing surgeon fatigue and surgery time, thus decreasing risks of infection and human error. In this paper, we introduce a novel algorithm for pupil detection tailored for eye images acquired through an unmodified microscope ocular. The proposed approach, the Hough transform, and six state-of-the-art pupil detection algorithms were evaluated on over 4000 hand-labeled images acquired from a digital operating microscope with a non-intrusive monitoring system for the surgeon eyes integrated. Our results show that the proposed method reaches detection rates up to 71% for an error of ≈3% w.r.t the input image diagonal; none of the state-of-the-art pupil detection algorithms performed satisfactorily. The algorithm and hand-labeled data set can be downloaded at:: www.ti.uni-tuebingen.de/perception.

  15. A Non-Intrusive Algorithm for Sensitivity Analysis of Chaotic Flow Simulations

    NASA Technical Reports Server (NTRS)

    Blonigan, Patrick J.; Wang, Qiqi; Nielsen, Eric J.; Diskin, Boris

    2017-01-01

    We demonstrate a novel algorithm for computing the sensitivity of statistics in chaotic flow simulations to parameter perturbations. The algorithm is non-intrusive but requires exposing an interface. Based on the principle of shadowing in dynamical systems, this algorithm is designed to reduce the effect of the sampling error in computing sensitivity of statistics in chaotic simulations. We compare the effectiveness of this method to that of the conventional finite difference method.

  16. Non-Intrusive Media Forensics Framework

    DTIC Science & Technology

    2012-03-01

    JPEG images via dct coefficient analysis ,” in Proc. of ECCV, 2006, vol. 3593, pp. 423–435. [20] S. Ye, Q.n Sun, and E.-C. Chang , “ Detecting digital...no universal method of detecting digital forgeries exists. Instead, several forensic tests must be designed to identify the fingerprints of a variety... methods designed to detect general forms globally and locally applied contrast enhancement, and show how the detection of localized contrast

  17. Non-intrusive detection of rotating stall in pump-turbines

    NASA Astrophysics Data System (ADS)

    Botero, F.; Hasmatuchi, V.; Roth, S.; Farhat, M.

    2014-10-01

    When operated far from their optimum conditions, pump-turbines may exhibit strong hydrodynamic instabilities, often called rotating stall, which lead to substantial increase of vibration and risk of mechanical failure. In the present study, we have investigated the flow filed in a model of radial pump-turbine with the help of tuft visualization, wall pressure measurement and structure-borne noise monitoring. As the rotation speed is increased, the machine is brought from its optimum operation to runaway with zero torque on the shaft. The runaway operation is characterized by a significant increase of pressure fluctuation at the rotor-stator interaction frequency. As the speed is further increased, the flow exhibits sub-synchronous instability, which rotates at 70% of the rotation frequency. Tuft visualization clearly shows that, as the instability evolves, the flow in a given distributor channel suddenly stalls and switches to reverse pumping mode in periodic way. We have also investigated the monitoring of the rotating stall with the help of vibration signals. A specific signal processing method, based on amplitude demodulation, was developed. The use of 2 accelerometers allows for the identification of the optimum carrier frequency by computing the cyclic coherence of vibration signals. This non-intrusive method is proved to be efficient in detecting the rotating stall instability and the number of stall cells. We strongly believe that it could be implemented in full scale pump-turbines.

  18. Non-intrusive calibration for three-dimensional particle imaging

    NASA Astrophysics Data System (ADS)

    Schosser, Constantin; Fuchs, Thomas; Hain, Rainer; Kähler, Christian J.

    2016-05-01

    This letter introduces a non-intrusive calibration scheme for three-dimensional (3D) optical flow velocimetry techniques. For these 3D techniques, including tomographic PIV and 3D-PTV, calibration targets need to be imaged within the measurement volume at different depth positions. However, for domains with limited access and with small dimensions, it is difficult or impossible to place a calibration target. Therefore, a non-intrusive calibration approach is proposed to overcome these drawbacks, by employing light reflections of a continuous wave laser in the measurement domain. The laser is translated to different locations, yielding a set of calibration points, comprising the spatial coordinates of the light reflections and their corresponding sensor coordinates.

  19. Non-Intrusive Gaze Tracking Using Artificial Neural Networks

    DTIC Science & Technology

    1994-01-05

    Artificial Neural Networks Shumeet Baluja & Dean...this paper appear in: Baluja, S. & Pomerleau, D.A. "Non-Intrusive Gaze Tracking Using Artificial Neural Networks ", Advances in Neural Information...document hLc-s been opproved t0T 011bhiC leleWOe cad ý’ir/4 its di stT-b’ution Ls •_nii•ite6. - Keywords Gaze Tracking, Artificial Neural Networks ,

  20. Non-intrusive speed sensor. [space shuttle main engine turbopumps

    NASA Technical Reports Server (NTRS)

    Maram, J.; Wyett, L.

    1984-01-01

    A computerized literature search was performed to identify candidate technologies for remote, non-intrusive speed sensing applications in Space Shuttle Main Engine (SSME) turbopumps. The three most promising technologies were subjected to experimental evaluation to quantify their performance characteristics under the harsh environmental requirements within the turbopumps. Although the infrared and microwave approaches demonstrated excellent cavitation immunity in laboratory tests, the variable-source magnetic speed sensor emerged as the most viable approach. Preliminary design of this speed sensor encountered no technical obstacles and resulted in viable and feasible speed nut, sensor housing, and sensor coil designs.

  1. Non-intrusive measurement of internal pressure and flow in pipelines using fiber Bragg grating

    NASA Astrophysics Data System (ADS)

    Salgado, Pedro; Filograno, Massimo L.; Senent, Fernando D.; Corredera, Pedro

    2013-10-01

    In this paper we propose and demonstrate a non-intrusive measurement method for internal pressure and water flow in hydraulic pipeline systems. Fiber Bragg Gratings are used to measure deformations in the external side of pipes under different working conditions for two different experiments. In the first experiment a PVC sewerage pipeline with a diameter of 90 mm was subjected to a variable air pressures up to 4 bars; in the second a PVC sewerage pipeline with a diameter of 32 mm was subjected to a water flow between 10 and 35 liters per minute.

  2. Non-intrusive flow measurements on a reentry vehicle

    NASA Technical Reports Server (NTRS)

    Miles, R. B.; Satavicca, D. A.; Zimmermann, G. M.

    1983-01-01

    This study evaluates the utility of various non-intrusive techniques for the measurement of the flow field on the windward side of the Space Shuttle or a similar re-entry vehicle. Included are linear (Rayleigh, Raman, Mie, Laser Doppler Velocimetry, Resonant Doppler Velocimetry) and nonlinear (Coherent Anti-Stokes Raman, Laser Induced Fluorescence) light scattering, electron beam fluorescence, thermal emission and mass spectroscopy. Flow field properties are taken from a nonequilibrium flow model by Shinn, Moss and Simmonds at NASA Langley. Conclusions are, when possible, based on quantitative scaling of known laboratory results to the conditions projected. Detailed discussion with researchers in the field contributed further to these conclusions and provided valuable insights regarding the experimental feasibility of each of the techniques.

  3. Non-Intrusive Impedance-Based Cable Tester

    NASA Technical Reports Server (NTRS)

    Medelius, Pedro J. (Inventor); Simpson, Howard J. (Inventor)

    1999-01-01

    A non-intrusive electrical cable tester determines the nature and location of a discontinuity in a cable through application of an oscillating signal to one end of the cable. The frequency of the oscillating signal is varied in increments until a minimum, close to zero voltage is measured at a signal injection point which is indicative of a minimum impedance at that point. The frequency of the test signal at which the minimum impedance occurs is then employed to determine the distance to the discontinuity by employing a formula which relates this distance to the signal frequency and the velocity factor of the cable. A numerically controlled oscillator is provided to generate the oscillating signal, and a microcontroller automatically controls operation of the cable tester to make the desired measurements and display the results. The device is contained in a portable housing which may be hand held to facilitate convenient use of the device in difficult to access locations.

  4. Non-intrusive Ensemble Kalman filtering for large scale geophysical models

    NASA Astrophysics Data System (ADS)

    Amour, Idrissa; Kauranne, Tuomo

    2016-04-01

    Advanced data assimilation techniques, such as variational assimilation methods, present often challenging implementation issues for large-scale models, both because of computational complexity and because of complexity of implementation. We present a non-intrusive wrapper library that addresses this problem by isolating the direct model and the linear algebra employed in data assimilation from each other completely. In this approach we have adopted a hybrid Variational Ensemble Kalman filter that combines Ensemble propagation with a 3DVAR analysis stage. The inverse problem of state and covariance propagation from prior to posterior estimates is thereby turned into a time-independent problem. This feature allows the linear algebra and minimization steps required in the variational step to be conducted outside the direct model and no tangent linear or adjoint codes are required. Communication between the model and the assimilation module is conducted exclusively via standard input and output files of the model. This non-intrusive approach is tested with the comprehensive 3D lake and shallow sea model COHERENS that is used to forecast and assimilate turbidity in lake Säkylän Pyhäjärvi in Finland, using both sparse satellite images and continuous real-time point measurements as observations.

  5. Reduction of Motion Artifacts and Improvement of R Peak Detecting Accuracy Using Adjacent Non-Intrusive ECG Sensors

    PubMed Central

    Choi, Minho; Jeong, Jae Jin; Kim, Seung Hun; Kim, Sang Woo

    2016-01-01

    Non-intrusive electrocardiogram (ECG) monitoring has many advantages: easy to measure and apply in daily life. However, motion noise in the measured signal is the major problem of non-intrusive measurement. This paper proposes a method to reduce the noise and to detect the R peaks of ECG in a stable manner in a sitting arrangement using non-intrusive sensors. The method utilizes two capacitive ECG sensors (cECGs) to measure ECG, and another two cECGs located adjacent to the sensors for ECG are added to obtain the information on motion. Then, active noise cancellation technique and the motion information are used to reduce motion noise. To verify the proposed method, ECG was measured indoors and during driving, and the accuracy of the detected R peaks was compared. After applying the method, the sum of sensitivity and positive predictivity increased 8.39% on average and 26.26% maximally in the data. Based on the results, it was confirmed that the motion noise was reduced and that more reliable R peak positions could be obtained by the proposed method. The robustness of the new ECG measurement method will elicit benefits to various health care systems that require noninvasive heart rate or heart rate variability measurements. PMID:27196910

  6. Mathematical Methods for Non-Intrusive Load Monitoring

    DTIC Science & Technology

    2010-06-01

    considered. 15. SUBJECT TERMS 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT Same as Report (SAR) 18. NUMBER OF PAGES 197 19a. NAME OF...ethernet (IEEE 802.3) or Bluetooth (IEEE 802.15.1) or ZigBee , or to change the storage system to, for example, a microSD card. An FPGA permits the

  7. A Non-Intrusive GMA Welding Process Quality Monitoring System Using Acoustic Sensing

    PubMed Central

    Cayo, Eber Huanca; Alfaro, Sadek Crisostomo Absi

    2009-01-01

    Most of the inspection methods used for detection and localization of welding disturbances are based on the evaluation of some direct measurements of welding parameters. This direct measurement requires an insertion of sensors during the welding process which could somehow alter the behavior of the metallic transference. An inspection method that evaluates the GMA welding process evolution using a non-intrusive process sensing would allow not only the identification of disturbances during welding runs and thus reduce inspection time, but would also reduce the interference on the process caused by the direct sensing. In this paper a nonintrusive method for weld disturbance detection and localization for weld quality evaluation is demonstrated. The system is based on the acoustic sensing of the welding electrical arc. During repetitive tests in welds without disturbances, the stability acoustic parameters were calculated and used as comparison references for the detection and location of disturbances during the weld runs. PMID:22399990

  8. A Non-Intrusive GMA Welding Process Quality Monitoring System Using Acoustic Sensing.

    PubMed

    Cayo, Eber Huanca; Alfaro, Sadek Crisostomo Absi

    2009-01-01

    Most of the inspection methods used for detection and localization of welding disturbances are based on the evaluation of some direct measurements of welding parameters. This direct measurement requires an insertion of sensors during the welding process which could somehow alter the behavior of the metallic transference. An inspection method that evaluates the GMA welding process evolution using a non-intrusive process sensing would allow not only the identification of disturbances during welding runs and thus reduce inspection time, but would also reduce the interference on the process caused by the direct sensing. In this paper a nonintrusive method for weld disturbance detection and localization for weld quality evaluation is demonstrated. The system is based on the acoustic sensing of the welding electrical arc. During repetitive tests in welds without disturbances, the stability acoustic parameters were calculated and used as comparison references for the detection and location of disturbances during the weld runs.

  9. Non-Intrusive Load Monitoring Approaches for Disaggregated Energy Sensing: A Survey

    PubMed Central

    Zoha, Ahmed; Gluhak, Alexander; Imran, Muhammad Ali; Rajasegarar, Sutharshan

    2012-01-01

    Appliance Load Monitoring (ALM) is essential for energy management solutions, allowing them to obtain appliance-specific energy consumption statistics that can further be used to devise load scheduling strategies for optimal energy utilization. Fine-grained energy monitoring can be achieved by deploying smart power outlets on every device of interest; however it incurs extra hardware cost and installation complexity. Non-Intrusive Load Monitoring (NILM) is an attractive method for energy disaggregation, as it can discern devices from the aggregated data acquired from a single point of measurement. This paper provides a comprehensive overview of NILM system and its associated methods and techniques used for disaggregated energy sensing. We review the state-of-the art load signatures and disaggregation algorithms used for appliance recognition and highlight challenges and future research directions. PMID:23223081

  10. Active, Non-Intrusive Inspection Technologies for Homeland Defense

    SciTech Connect

    James L. Jones

    2003-06-01

    Active, non-intrusive inspection or interrogation technologies have been used for 100 years - with the primary focus being radiographic imaging. During the last 50 years, various active interrogation systems have been investigated and most have revealed many unique and interesting capabilities and advantages that have already benefited the general public. Unfortunately, except for medical and specific industrial applications, these unique capabilities have not been widely adopted, largely due to the complexity of the technology, the overconfident reliance on passive detection systems to handle most challenges, and the unrealistic public concerns regarding radiation safety issues for a given active inspection deployment. The unique homeland security challenges facing the United States today are inviting more "out-of-the-box" solutions and are demanding the effective technological solutions that only active interrogation systems can provide. While revolutionary new solutions are always desired, these technology advancements are rare, and when found, usually take a long time to fully understand and implement for a given application. What's becoming more evident is that focusing on under-developed, but well-understood, active inspection technologies can provide many of the needed "out-of-the-box" solutions. This paper presents a brief historical overview of active interrogation. It identifies some of the major homeland defense challenges being confronted and the commercial and research technologies presently available and being pursued. Finally, the paper addresses the role of the Idaho National Engineering and Environmental Laboratory and its partner, the Idaho Accelerator Center at Idaho State University, in promoting and developing active inspection technologies for homeland defense.

  11. Non-Intrusive Techniques of Inspections During the Pre-Launch Phase of Space Vehicle

    NASA Technical Reports Server (NTRS)

    Thirumalainambi, Rejkumar; Bardina, Jorge E.

    2005-01-01

    This paper addresses a method of non-intrusive local inspection of surface and sub-surface conditions, interfaces, laminations and seals in both space vehicle and ground operations with an integrated suite of imaging sensors during pre-launch operations. It employs an advanced Raman spectrophotometer with additional spectrophotometers and lidar mounted on a flying robot to constantly monitor the space hardware as well as inner surface of the vehicle and ground operations hardware. This paper addresses a team of micro flying robots with necessary sensors and photometers to monitor the entire space vehicle internally and externally. The micro flying robots can reach altitude with least amount of energy, where astronauts have difficulty in reaching and monitoring the materials and subsurface faults. The micro flying robot has an embedded fault detection system which acts as an advisory system and in many cases micro flying robots act as a Supervisor to fix the problems. As missions expand to a sustainable presence in the Moon, and extend for durations longer than one year in lunar outpost, the effectiveness of the instrumentation and hardware has to be revolutionized if NASA is to meet high levels of mission safety, reliability, and overall success. The micro flying robot uses contra-rotating propellers powered by an ultra-thin, ultrasonic motor with currently the world's highest power weight ratio, and is balanced in mid-air by means of the world's first stabilizing mechanism using a linear actuator. The essence of micromechatronics has been brought together in high-density mounting technology to minimize the size and weight. The robot can take suitable payloads of photometers, embedded chips for image analysis and micro pumps for sealing cracks or fixing other material problems. This paper also highlights advantages that this type of non-intrusive techniques offer over costly and monolithic traditional techniques.

  12. A non-intrusive reduced-order model for compressible fluid and fractured solid coupling and its application to blasting

    NASA Astrophysics Data System (ADS)

    Xiao, D.; Yang, P.; Fang, F.; Xiang, J.; Pain, C. C.; Navon, I. M.; Chen, M.

    2017-02-01

    This work presents the first application of a non-intrusive reduced order method to model solid interacting with compressible fluid flows to simulate crack initiation and propagation. In the high fidelity model, the coupling process is achieved by introducing a source term into the momentum equation, which represents the effects of forces of the solid on the fluid. A combined single and smeared crack model with the Mohr-Coulomb failure criterion is used to simulate crack initiation and propagation. The non-intrusive reduced order method is then applied to compressible fluid and fractured solid coupled modelling where the computational cost involved in the full high fidelity simulation is high. The non-intrusive reduced order model (NIROM) developed here is constructed through proper orthogonal decomposition (POD) and a radial basis function (RBF) multi-dimensional interpolation method. The performance of the NIROM for solid interacting with compressible fluid flows, in the presence of fracture models, is illustrated by two complex test cases: an immersed wall in a fluid and a blasting test case. The numerical simulation results show that the NIROM is capable of capturing the details of compressible fluids and fractured solids while the CPU time is reduced by several orders of magnitude. In addition, the issue of whether or not to subtract the mean from the snapshots before applying POD is discussed in this paper. It is shown that solutions of the NIROM, without mean subtracted before constructing the POD basis, captured more details than the NIROM with mean subtracted from snapshots.

  13. Non-Intrusive Electric Appliances Load Monitoring System-Experiment for Real Household-

    NASA Astrophysics Data System (ADS)

    Murata, Hiroshi; Onoda, Takashi; Yoshimoto, Katsuhisa; Nakano, Yukio; Kondo, Syuhei

    This paper presents applying results of four estimation algorithms of non-intrusive monitoring system for real household. We conclude that all algorithms have practicable ability. 1) support vector machine(SVM): SVM was used to estimate ON/OFF states for fluorescent and refrigerator. SVM has the performance equivalent to best performance of sigmoid function networks(SFN). However, SVM has high estimating ability constantly. 2) RBF networks(RBFN): RBFN was used to estimate power consumption for air conditioner. RBFN has the performance equivalent to best performance of SFN. However, RBFN has high estimating ability constantly. 3) step change detection method(SCD): SCD was used to estimate ON/OFF states and power consumption for IH cooking range. SCD does not need the necessary learning process for SFN and has higher estimating ability than SFN. 4) spectrum reference method(SRM): SRM was used to estimate working conditions for rice cocker and washing machine. SRM is able to estimate these working conditions that cannot be estimated by earlier methods.

  14. A Non-Intrusive Cyber Physical Social Sensing Solution to People Behavior Tracking: Mechanism, Prototype, and Field Experiments.

    PubMed

    Jia, Yunjian; Zhou, Zhenyu; Chen, Fei; Duan, Peng; Guo, Zhen; Mumtaz, Shahid

    2017-01-13

    Tracking people's behaviors is a main category of cyber physical social sensing (CPSS)-related people-centric applications. Most tracking methods utilize camera networks or sensors built into mobile devices such as global positioning system (GPS) and Bluetooth. In this article, we propose a non-intrusive wireless fidelity (Wi-Fi)-based tracking method. To show the feasibility, we target tracking people's access behaviors in Wi-Fi networks, which has drawn a lot of interest from the academy and industry recently. Existing methods used for acquiring access traces either provide very limited visibility into media access control (MAC)-level transmission dynamics or sometimes are inflexible and costly. In this article, we present a passive CPSS system operating in a non-intrusive, flexible, and simplified manner to overcome above limitations. We have implemented the prototype on the off-the-shelf personal computer, and performed real-world deployment experiments. The experimental results show that the method is feasible, and people's access behaviors can be correctly tracked within a one-second delay.

  15. A Non-Intrusive Cyber Physical Social Sensing Solution to People Behavior Tracking: Mechanism, Prototype, and Field Experiments

    PubMed Central

    Jia, Yunjian; Zhou, Zhenyu; Chen, Fei; Duan, Peng; Guo, Zhen; Mumtaz, Shahid

    2017-01-01

    Tracking people’s behaviors is a main category of cyber physical social sensing (CPSS)-related people-centric applications. Most tracking methods utilize camera networks or sensors built into mobile devices such as global positioning system (GPS) and Bluetooth. In this article, we propose a non-intrusive wireless fidelity (Wi-Fi)-based tracking method. To show the feasibility, we target tracking people’s access behaviors in Wi-Fi networks, which has drawn a lot of interest from the academy and industry recently. Existing methods used for acquiring access traces either provide very limited visibility into media access control (MAC)-level transmission dynamics or sometimes are inflexible and costly. In this article, we present a passive CPSS system operating in a non-intrusive, flexible, and simplified manner to overcome above limitations. We have implemented the prototype on the off-the-shelf personal computer, and performed real-world deployment experiments. The experimental results show that the method is feasible, and people’s access behaviors can be correctly tracked within a one-second delay. PMID:28098772

  16. Characterization methods

    SciTech Connect

    Glass, J.T.

    1993-01-01

    Methods discussed in this compilation of notes and diagrams are Raman spectroscopy, scanning electron microscopy, transmission electron microscopy, and other surface analysis techniques (auger electron spectroscopy, x-ray photoelectron spectroscopy, electron energy loss spectroscopy, and scanning tunnelling microscopy). A comparative evaluation of different techniques is performed. In-vacuo and in-situ analyses are described.

  17. Non-Intrusive Measurement Techniques Applied to the Hybrid Solid Fuel Degradation

    NASA Astrophysics Data System (ADS)

    Cauty, F.

    2004-10-01

    The knowledge of the solid fuel regression rate and the time evolution of the grain geometry are requested for hybrid motor design and control of its operating conditions. Two non-intrusive techniques (NDT) have been applied to hybrid propulsion : both are based on wave propagation, the X-rays and the ultrasounds, through the materials. X-ray techniques allow local thickness measurements (attenuated signal level) using small probes or 2D images (Real Time Radiography), with a link between the size of field of view and accuracy. Beside the safety hazards associated with the high-intensity X-ray systems, the image analysis requires the use of quite complex post-processing techniques. The ultrasound technique is more widely used in energetic material applications, including hybrid fuels. Depending upon the transducer size and the associated equipment, the application domain is large, from tiny samples to the quad-port wagon wheel grain of the 1.1 MN thrust HPDP motor. The effect of the physical quantities has to be taken into account in the wave propagation analysis. With respect to the various applications, there is no unique and perfect experimental method to measure the fuel regression rate. The best solution could be obtained by combining two techniques at the same time, each technique enhancing the quality of the global data.

  18. Electrical signature analysis applications for non-intrusive automotive alternator diagnostics

    SciTech Connect

    Ayers, C.W.

    1996-03-01

    Automotive alternators are designed to supply power for automobile engine ignition systems as well as charge the storage battery. This product is used in a large market where consumers are concerned with acoustic noise and vibration that comes from the unit. as well as overall quality and dependability. Alternators and generators in general are used in industries other than automotive, such as transportation and airline industries and in military applications. Their manufacturers are interested in pursuing state-of-the-art methods to achieve higher quality and reduced costs. Preliminary investigations of non-intrusive diagnostic techniques utilizing the inherent voltage signals of alternators have been performed with promising results. These techniques are based on time and frequency domain analyses of specially conditioned signals taken from several alternators under various test conditions. This paper discusses investigations that show correlations of the alternator output voltage to airborne noise production. In addition these signals provide insight into internal magnetic characteristics that relate to design and/or assembly problems.

  19. Non-Intrusive Magneto-Optic Detecting System for Investigations of Air Switching Arcs

    NASA Astrophysics Data System (ADS)

    Zhang, Pengfei; Zhang, Guogang; Dong, Jinlong; Liu, Wanying; Geng, Yingsan

    2014-07-01

    In current investigations of electric arc plasmas, experiments based on modern testing technology play an important role. To enrich the testing methods and contribute to the understanding and grasping of the inherent mechanism of air switching arcs, in this paper, a non-intrusive detecting system is described that combines the magneto-optic imaging (MOI) technique with the solution to inverse electromagnetic problems. The detecting system works in a sequence of main steps as follows: MOI of the variation of the arc flux density over a plane, magnetic field information extracted from the magneto-optic (MO) images, arc current density distribution and spatial pattern reconstruction by inverting the resulting field data. Correspondingly, in the system, an MOI set-up is designed based on the Faraday effect and the polarization properties of light, and an intelligent inversion algorithm is proposed that involves simulated annealing (SA). Experiments were carried out for high current (2 kA RMS) discharge cases in a typical low-voltage switchgear. The results show that the MO detection system possesses the advantages of visualization, high resolution and response, and electrical insulation, which provides a novel diagnostics tool for further studies of the arc.

  20. Extracting Features from an Electrical Signal of a Non-Intrusive Load Monitoring System

    NASA Astrophysics Data System (ADS)

    Figueiredo, Marisa B.; de Almeida, Ana; Ribeiro, Bernardete; Martins, António

    Improving energy efficiency by monitoring household electrical consumption is of significant importance with the present-day climate change concerns. A solution for the electrical consumption management problem is the use of a non-intrusive load monitoring system (NILM). This system captures the signals from the aggregate consumption, extracts the features from these signals and classifies the extracted features in order to identify the switched on appliances. An effective device identification (ID) requires a signature to be assigned for each appliance. Moreover, to specify an ID for each device, signal processing techniques are needed for extracting the relevant features. This paper describes a technique for the steady-states recognition in an electrical digital signal as the first stage for the implementation of an innovative NILM. Furthermore, the final goal is to develop an intelligent system for the identification of the appliances by automated learning. The proposed approach is based on the ratio value between rectangular areas defined by the signal samples. The computational experiments show the method effectiveness for the accurate steady-states identification in the electrical input signals.

  1. Non-Intrusive Load Monitoring of HVAC Components using Signal Unmixing

    SciTech Connect

    Rahimpour, Alireza; Qi, Hairong; Fugate, David L; Kuruganti, Teja

    2015-01-01

    Heating, Ventilating and Air Conditioning units (HVAC) are a major electrical energy consumer in buildings. Monitoring of the operation and energy consumption of HVAC would increase the awareness of building owners and maintenance service providers of the condition and quality of performance of these units, enabling conditioned-based maintenance which would help achieving higher energy efficiency. In this paper, a novel non-intrusive load monitoring method based on group constrained non-negative matrix factorization is proposed for monitoring the different components of HVAC unit by only measuring the whole building aggregated power signal. At the first level of this hierarchical approach, power consumption of the building is decomposed to energy consumption of the HVAC unit and all the other electrical devices operating in the building such as lighting and plug loads. Then, the estimated power signal of the HVAC is used for estimating the power consumption profile of the HVAC major electrical loads such as compressors, condenser fans and indoor blower. Experiments conducted on real data collected from a building testbed maintained at the Oak Ridge National Laboratory (ORNL) demonstrate high accuracy on the disaggregation task.

  2. Uncertainty propagation for nonlinear vibrations: A non-intrusive approach

    NASA Astrophysics Data System (ADS)

    Panunzio, A. M.; Salles, Loic; Schwingshackl, C. W.

    2017-02-01

    The propagation of uncertain input parameters in a linear dynamic analysis is reasonably well established today, but with the focus of the dynamic analysis shifting towards nonlinear systems, new approaches is required to compute the uncertain nonlinear responses. A combination of stochastic methods (Polynomial Chaos Expansion, PCE) with an Asymptotic Numerical Method (ANM) for the solution of the nonlinear dynamic systems is presented to predict the propagation of random input uncertainties and assess their influence on the nonlinear vibrational behaviour of a system. The proposed method allows the computation of stochastic resonance frequencies and peak amplitudes based on multiple input uncertainties, leading to a series of uncertain nonlinear dynamic responses. One of the main challenges when using the PCE is thereby the Gibbs phenomenon, which can heavily impact the resulting stochastic nonlinear response by introducing spurious oscillations. A novel technique to avoid the Gibbs phenomenon is be presented in this paper, leading to high quality frequency response predictions. A comparison of the proposed stochastic nonlinear analysis technique to traditional Monte Carlo simulations, demonstrates comparable accuracy at a significantly reduced computational cost, thereby validating the proposed approach.

  3. Hierarchically Structured Non-Intrusive Sign Language Recognition. Chapter 2

    NASA Technical Reports Server (NTRS)

    Zieren, Jorg; Zieren, Jorg; Kraiss, Karl-Friedrich

    2007-01-01

    This work presents a hierarchically structured approach at the nonintrusive recognition of sign language from a monocular frontal view. Robustness is achieved through sophisticated localization and tracking methods, including a combined EM/CAMSHIFT overlap resolution procedure and the parallel pursuit of multiple hypotheses about hands position and movement. This allows handling of ambiguities and automatically corrects tracking errors. A biomechanical skeleton model and dynamic motion prediction using Kalman filters represents high level knowledge. Classification is performed by Hidden Markov Models. 152 signs from German sign language were recognized with an accuracy of 97.6%.

  4. New in-situ, non-intrusive calibration

    NASA Astrophysics Data System (ADS)

    Zunino, Heather; Adrian, Ronald; Ding, Liuyang; Prestridge, Kathy

    2014-11-01

    Tomographic particle image velocimetry (PIV) experiments require precise and accurate camera calibration. Standard techniques make assumptions about hard-to-measure camera parameters (i.e. optical axis angle, distortions, etc.)-reducing the calibration accuracy. Additionally, vibrations and slight movements after calibration may cause significant errors-particularly for tomographic PIV. These problems are exacerbated when a calibration target cannot be placed within the test section. A new PIV camera calibration method has been developed to permit precise calibration without placing a calibration target inside the test section or scanning the target over a volume. The method is capable of correcting for dynamic calibration changes occurring between PIV laser pulses. A transparent calibration plate with fine marks on both sides is positioned on the test section window. Dual-plane mapping makes it possible to determine a mapping function containing both position and angular direction of central rays from particles. From this information, central rays can be traced into the test section with high accuracy. Image distortion by the lens and refraction at various air-glass-liquid interfaces are accounted for, and no information about the position or angle of the camera(s) is required.

  5. Non-intrusive Experimental Study on Nuclear Fuel Assembly Response to Seismic Loads

    NASA Astrophysics Data System (ADS)

    Weichselbaum, Noah A.

    length run times needed to capture the effect of the seismic transients on the fluid velocity field. A custom DIC system is used to non-intrusively measure the structural displacements at the same time the PIV measurements are recorded. With this non-intrusive system, simultaneous full field fluid velocity measurements and structural response measurements to seismic forcing are obtained for the first time. Furthermore, the RIM facility allows for fluid measurements within the fuel bundle that have not been accessible before. This work presents data on fluid structure interaction (FSI) measurements in still fluid, and with axial flow at Reynolds number typical to a PWR, with seismic forcing from a shake table. Analysis of the cases in still water will show development of a vertical pulsatile flow, in addition to a cross flow, created by the horizontal oscillations of the fuel bundle driving pressure gradients in both the vertical and spanwise directions. Furthermore in still water the onset of vortices being shed from the bundle oscillations is found to occur at a critical Keulegan Carpenter number which has a direct impact on bundle dynamics. The insights from the still water cases are paramount in improving the understanding of what occurs in the more complex case with axial flow, where the vertical pulsatile flow is found to be prevalent as well. Additionally this data provides for the first time high spatial and temporal full field fluid velocity measurements that can be used for validation of numerical codes.

  6. Non-intrusive uncertainty quantification using reduced cubature rules

    NASA Astrophysics Data System (ADS)

    van den Bos, L. M. M.; Koren, B.; Dwight, R. P.

    2017-03-01

    For the purpose of uncertainty quantification with collocation, a method is proposed for generating families of one-dimensional nested quadrature rules with positive weights and symmetric nodes. This is achieved through a reduction procedure: we start with a high-degree quadrature rule with positive weights and remove nodes while preserving symmetry and positivity. This is shown to be always possible, by a lemma depending primarily on Carathéodory's theorem. The resulting one-dimensional rules can be used within a Smolyak procedure to produce sparse multi-dimensional rules, but weight positivity is lost then. As a remedy, the reduction procedure is directly applied to multi-dimensional tensor-product cubature rules. This allows to produce a family of sparse cubature rules with positive weights, competitive with Smolyak rules. Finally the positivity constraint is relaxed to allow more flexibility in the removal of nodes. This gives a second family of sparse cubature rules, in which iteratively as many nodes as possible are removed. The new quadrature and cubature rules are applied to test problems from mathematics and fluid dynamics. Their performance is compared with that of the tensor-product and standard Clenshaw-Curtis Smolyak cubature rule.

  7. Department of Defense counterdrug technology development of non-intrusive inspection systems

    NASA Astrophysics Data System (ADS)

    Pennella, John J.

    1997-02-01

    The Naval Surface Warfare Center Dahlgren Division serves as the executive agent for the DoD's Contraband Detection and Cargo Container Inspection Technology Development Program. The goal of the DoD non-intrusive inspection (NII) program is to develop prototype equipment that can be used to inspect containers and vehicles, quickly and in large numbers without unnecessary delays in the movement of legitimate cargo. This paper summaries the past accomplishments of the program, current status, and future plans.

  8. On the Non-Intrusive Determination of Electron Density in the Sheath of a Spherical Probe

    DTIC Science & Technology

    2007-04-20

    PAGE 18. NUMBER OF PAGES 17. LIMITATION OF ABSTRACT On the Non-intrusive Determination of Electron Density in the Sheath of a Spherical Probe David N...07-9033 Approved for public release; distribution is unlimited. Unclassified Unclassified Unclassified UL 15 David Walker (202) 767-2248 Plasma...approximations where the ion flow velocity is well known from the Bohm condition. When plasmas become highly collisional, the analysis is further

  9. Non-intrusive ultrasonic liquid-in-line detector for small diameter tubes

    DOEpatents

    Piper, Thomas C.

    1982-01-01

    An arrangement for deleting liquid in a line, using non-intrusive ultrasonic techniques is disclosed. In this arrangement, four piezoelectric crystals are arranged in pairs about a 0.072 inch o.d. pipe. An ultrasonic tone burst is transmitted along the pipe, between crystal pairs, and the amplitude of the received tone burst indicates the absence/presence of liquid in the pipe.

  10. Optimal Placement of Non-Intrusive Waste Heat Recovery Devices in Exhaust Ducts

    DTIC Science & Technology

    2015-06-01

    exchangers for energy recovery in waste and biomass to energy technologies–I. Energy recovery from flue gas,” Appl. Therm. Eng., vol. 64, pp. 213...CODE 13. ABSTRACT (maximum 200 words) The Secretary of the Navy has ordered the U.S. Navy and Marine Corps to reduce energy usage. This study...explores how to optimize placement and size of a non-intrusive waste heat recovery device for energy recovery in exhaust ducts. Additionally, it

  11. Evaluation and analysis of non-intrusive techniques for detecting illicit substances

    SciTech Connect

    Micklich, B.J.; Roche, C.T.; Fink, C.L.; Yule, T.J.; Demirgian, J.C.; Kunz, T.D.; Ulvick, S.J.; Cui, J.

    1995-12-31

    Argonne National Laboratory (ANL) and the Houston Advanced Research Center (HARC) have been tasked by the Counterdrug Technology Assessment Center of the Office of National Drug Control Policy to conduct evaluations and analyses of technologies for the non-intrusive inspection of containers for illicit substances. These technologies span the range of nuclear, X-ray, and chemical techniques used in nondestructive sample analysis. ANL has performed assessments of nuclear and X-ray inspection concepts and undertaken site visits with developers to understand the capabilities and the range of applicability of candidate systems. ANL and HARC have provided support to law enforcement agencies (LEAs), including participation in numerous field studies. Both labs have provided staff to assist in the Narcotics Detection Technology Assessment (NDTA) program for evaluating drug detection systems. Also, the two labs are performing studies of drug contamination of currency. HARC has directed technical evaluations of automated ballistics imaging and identification systems under consideration by law enforcement agencies. ANL and HARC have sponsored workshops and a symposium, and are participating in a Non-Intrusive Inspection Study being led by Dynamics Technology, Incorporated.

  12. Non-intrusive optical study of gas and its exchange in human maxillary sinuses

    NASA Astrophysics Data System (ADS)

    Persson, L.; Andersson, M.; Svensson, T.; Cassel-Engquist, M.; Svanberg, K.; Svanberg, S.

    2007-07-01

    We demonstrate a novel non-intrusive technique based on tunable diode laser absorption spectroscopy to investigate human maxillary sinuses in vivo. The technique relies on the fact that free gases have much sharper absorption features (typical a few GHz) than the surrounding tissue. Molecular oxygen was detected at 760 nm. Volunteers have been investigated by injecting near-infrared light fibre-optically in contact with the palate inside the mouth. The multiply scattered light was detected externally by a handheld probe on and around the cheek bone. A significant signal difference in oxygen imprint was observed when comparing volunteers with widely different anamnesis regarding maxillary sinus status. Control measurements through the hand and through the cheek below the cheekbone were also performed to investigate any possible oxygen offset in the setup. These provided a consistently non-detectable signal level. The passages between the nasal cavity and the maxillary sinuses were also non-intrusively optically studied, to the best of our knowledge for the first time. These measurements provide information on the channel conductivity which may prove useful in facial sinus diagnostics. The results suggest that a clinical trial together with an ear-nose-throat (ENT) clinic should be carried out to investigate the clinical use of the new technique.

  13. Non-intrusive load monitoring systems: Considerations for use and potential applications

    SciTech Connect

    Sharp, T.R.

    1994-12-31

    The value of measured energy performance data and the desire to acquire them without the cost, complexity, and intrusiveness of standard submetering techniques have led to recent research on non-intrusive load monitoring systems. These systems offer installation simplicity and the ability to discriminate important load changes through high-resolution, higher-speed sampling at a central monitoring point such as a building`s electrical service entrance. Important hardware and installation considerations learned from Oak Ridge National Laboratory`s (ORNL) experience with these systems are reviewed. In addition, the ability to discern important load changes in residential and commercial buildings using these systems is discussed based on recent ORNL experiments in two buildings. Potential applications, with examples, are also discussed. Using a non-intrusive load monitoring system, an experienced user can collect valuable building power profiles that provide insight into building operations, energy use, demand, and building systems problems easily and at low cost. These systems, when available, could be valuable to DSM and energy management professionals, utilities, researchers, building management firms, energy service companies, and others.

  14. Non-intrusive head movement analysis of videotaped seizures of epileptic origin.

    PubMed

    Mandal, Bappaditya; Eng, How-Lung; Lu, Haiping; Chan, Derrick W S; Ng, Yen-Ling

    2012-01-01

    In this work we propose a non-intrusive video analytic system for patient's body parts movement analysis in Epilepsy Monitoring Unit. The system utilizes skin color modeling, head/face pose template matching and face detection to analyze and quantify the head movements. Epileptic patients' heads are analyzed holistically to infer seizure and normal random movements. The patient does not require to wear any special clothing, markers or sensors, hence it is totally non-intrusive. The user initializes the person-specific skin color and selects few face/head poses in the initial few frames. The system then tracks the head/face and extracts spatio-temporal features. Support vector machines are then used on these features to classify seizure-like movements from normal random movements. Experiments are performed on numerous long hour video sequences captured in an Epilepsy Monitoring Unit at a local hospital. The results demonstrate the feasibility of the proposed system in pediatric epilepsy monitoring and seizure detection.

  15. A Web-Based Non-Intrusive Ambient System to Measure and Classify Activities of Daily Living

    PubMed Central

    Urwyler, Prabitha; Rampa, Luca; Müri, René; Mosimann, Urs P

    2014-01-01

    Background The number of older adults in the global population is increasing. This demographic shift leads to an increasing prevalence of age-associated disorders, such as Alzheimer’s disease and other types of dementia. With the progression of the disease, the risk for institutional care increases, which contrasts with the desire of most patients to stay in their home environment. Despite doctors’ and caregivers’ awareness of the patient’s cognitive status, they are often uncertain about its consequences on activities of daily living (ADL). To provide effective care, they need to know how patients cope with ADL, in particular, the estimation of risks associated with the cognitive decline. The occurrence, performance, and duration of different ADL are important indicators of functional ability. The patient’s ability to cope with these activities is traditionally assessed with questionnaires, which has disadvantages (eg, lack of reliability and sensitivity). Several groups have proposed sensor-based systems to recognize and quantify these activities in the patient’s home. Combined with Web technology, these systems can inform caregivers about their patients in real-time (eg, via smartphone). Objective We hypothesize that a non-intrusive system, which does not use body-mounted sensors, video-based imaging, and microphone recordings would be better suited for use in dementia patients. Since it does not require patient’s attention and compliance, such a system might be well accepted by patients. We present a passive, Web-based, non-intrusive, assistive technology system that recognizes and classifies ADL. Methods The components of this novel assistive technology system were wireless sensors distributed in every room of the participant’s home and a central computer unit (CCU). The environmental data were acquired for 20 days (per participant) and then stored and processed on the CCU. In consultation with medical experts, eight ADL were classified

  16. Non-intrusive tunable resonant microwave cavity for optical detected magnetic resonance of NV centres in nanodiamonds

    NASA Astrophysics Data System (ADS)

    Le Floch, Jean-Michel; Bradac, Carlo; Volz, Thomas; Tobar, Michael E.; Castelletto, Stefania

    2013-12-01

    Optically detected magnetic resonance (ODMR) in nanodiamond nitrogen-vacancy (NV) centres is usually achieved by applying a microwave field delivered by micron-size wires, strips or antennas directly positioned in very close proximity (~ μm) of the nanodiamond crystals. The microwave field couples evanescently with the ground state spin transition of the NV centre (2.87 GHz at zero magnetic field), which results in a reduction of the centre photoluminescence. We propose an alternative approach based on the construction of a dielectric resonator. We show that such a resonator allows for the efficient detection of NV spins in nanodiamonds without the constraints associated to the laborious positioning of the microwave antenna next to the nanodiamonds, providing therefore improved flexibility. The resonator is based on a tunable Transverse Electric Mode in a dielectric-loaded cavity, and we demonstrate that the resonator can detect single NV centre spins in nanodiamonds using less microwave power than alternative techniques in a non-intrusive manner. This method can achieve higher precision measurement of ODMR of paramagnetic defects spin transition in the micro to millimetre-wave frequency domain. Our approach would permit the tracking of NV centres in biological solutions rather than simply on the surface, which is desirable in light of the recently proposed applications of using nanodiamonds containing NV centres for spin labelling in biological systems with single spin and single particle resolution.

  17. Evaluation of non-intrusive flow measurement techniques for a re-entry flight experiment

    NASA Technical Reports Server (NTRS)

    Miles, R. B.; Santavicca, D. A.; Zimmermann, M.

    1983-01-01

    This study evaluates various non-intrusive techniques for the measurement of the flow field on the windward side of the Space Shuttle orbiter or a similar reentry vehicle. Included are linear (Rayleigh, Raman, Mie, Laser Doppler Velocimetry, Resonant Doppler Velocimetry) and nonlinear (Coherent Anti-Stokes Raman, Laser-Induced Fluorescence) light scattering, electron-beam fluorescence, thermal emission, and mass spectroscopy. Flow-field properties were taken from a nonequilibrium flow model by Shinn, Moss, and Simmonds at the NASA Langley Research Center. Conclusions are, when possible, based on quantitative scaling of known laboratory results to the conditions projected. Detailed discussion with researchers in the field contributed further to these conclusions and provided valuable insights regarding the experimental feasibility of each of the techniques.

  18. Non-intrusive high voltage measurement using slab coupled optical sensors

    NASA Astrophysics Data System (ADS)

    Stan, Nikola; Chadderdon, Spencer; Selfridge, Richard H.; Schultz, Stephen M.

    2014-03-01

    We present an optical fiber non-intrusive sensor for measuring high voltage transients. The sensor converts the unknown voltage to electric field, which is then measured using slab-coupled optical fiber sensor (SCOS). Since everything in the sensor except the electrodes is made of dielectric materials and due to the small field sensor size, the sensor is minimally perturbing to the measured voltage. We present the details of the sensor design, which eliminates arcing and minimizes local dielectric breakdown using Teflon blocks and insulation of the whole structure with transformer oil. The structure has a capacitance of less than 3pF and resistance greater than 10 GΩ. We show the measurement of 66.5 kV pulse with a 32.6μs time constant. The measurement matches the expected value of 67.8 kV with less than 2% error.

  19. Multifidelity, Multidisciplinary Design Under Uncertainty with Non-Intrusive Polynomial Chaos

    NASA Technical Reports Server (NTRS)

    West, Thomas K., IV; Gumbert, Clyde

    2017-01-01

    The primary objective of this work is to develop an approach for multifidelity uncertainty quantification and to lay the framework for future design under uncertainty efforts. In this study, multifidelity is used to describe both the fidelity of the modeling of the physical systems, as well as the difference in the uncertainty in each of the models. For computational efficiency, a multifidelity surrogate modeling approach based on non-intrusive polynomial chaos using the point-collocation technique is developed for the treatment of both multifidelity modeling and multifidelity uncertainty modeling. Two stochastic model problems are used to demonstrate the developed methodologies: a transonic airfoil model and multidisciplinary aircraft analysis model. The results of both showed the multifidelity modeling approach was able to predict the output uncertainty predicted by the high-fidelity model as a significant reduction in computational cost.

  20. Non-intrusive Packet-Layer Model for Monitoring Video Quality of IPTV Services

    NASA Astrophysics Data System (ADS)

    Yamagishi, Kazuhisa; Hayashi, Takanori

    Developing a non-intrusive packet-layer model is required to passively monitor the quality of experience (QoE) during service. We propose a packet-layer model that can be used to estimate the video quality of IPTV using quality parameters derived from transmitted packet headers. The computational load of the model is lighter than that of the model that takes video signals and/or video-related bitstream information such as motion vectors as input. This model is applicable even if the transmitted bitstream information is encrypted because it uses transmitted packet headers rather than bitstream information. For developing the model, we conducted three extensive subjective quality assessments for different encoders and decoders (codecs), and video content. Then, we modeled the subjective video quality assessment characteristics based on objective features affected by coding and packet loss. Finally, we verified the model's validity by applying our model to unknown data sets different from training data sets used above.

  1. Non-intrusive gesture recognition system combining with face detection based on Hidden Markov Model

    NASA Astrophysics Data System (ADS)

    Jin, Jing; Wang, Yuanqing; Xu, Liujing; Cao, Liqun; Han, Lei; Zhou, Biye; Li, Minggao

    2014-11-01

    A non-intrusive gesture recognition human-machine interaction system is proposed in this paper. In order to solve the hand positioning problem which is a difficulty in current algorithms, face detection is used for the pre-processing to narrow the search area and find user's hand quickly and accurately. Hidden Markov Model (HMM) is used for gesture recognition. A certain number of basic gesture units are trained as HMM models. At the same time, an improved 8-direction feature vector is proposed and used to quantify characteristics in order to improve the detection accuracy. The proposed system can be applied in interaction equipments without special training for users, such as household interactive television

  2. Evolution of optically nondestructive and data-non-intrusive credit card verifiers

    NASA Astrophysics Data System (ADS)

    Sumriddetchkajorn, Sarun; Intaravanne, Yuttana

    2010-04-01

    Since the deployment of the credit card, the number of credit card fraud cases has grown rapidly with a huge amount of loss in millions of US dollars. Instead of asking more information from the credit card's holder or taking risk through payment approval, a nondestructive and data-non-intrusive credit card verifier is highly desirable before transaction begins. In this paper, we review optical techniques that have been proposed and invented in order to make the genuine credit card more distinguishable than the counterfeit credit card. Several optical approaches for the implementation of credit card verifiers are also included. In particular, we highlight our invention on a hyperspectral-imaging based portable credit card verifier structure that offers a very low false error rate of 0.79%. Other key features include low cost, simplicity in design and implementation, no moving part, no need of an additional decoding key, and adaptive learning.

  3. Non-intrusive measurement of inner bore temperature of small arms using integrated ultrasonic transducers

    NASA Astrophysics Data System (ADS)

    Lévesque, D.; Pimentel, R.; Lord, M.; Beauchesne, A.; Kruger, S. E.; Stowe, R.; Wong, F.; Monchalin, J.-P.

    2016-02-01

    Management of thermal input to a small arms weapons system is a significant design and operational constraint. A collaborative project was initiated with the objective to measure non-intrusively the inner bore barrel temperature of a small arm during actual firing. The approach uses integrated ultrasonic transducers (IUTs) and the velocity temperature dependence of the longitudinal wave propagating through thickness. IUT is successfully implemented on a small arm at 3 locations and results from several firing tests are presented. The small but systematic increase in ultrasonic time delay of less than 1 ns after each firing shot is reliably measured, in agreement with a simple 1D model of heat conduction, and measured temperature rises are consistent with the thicknesses at the different locations. The evaluation of the peak inner bore temperatures using IUT and their validation using eroding surface thermocouples at the same locations in the barrel are discussed.

  4. Non intrusive sensors -- An answer to annulus pressure monitoring in subsea wellhead equipment

    SciTech Connect

    Adamek, F.C.; Jennings, C.; Aarskog, A.

    1995-12-01

    On offshore platform and jackup surface wellhead completions, there is the potential for leakage from the high pressure production tubing and casing strings into the low pressure outer casing string, or from poor cementing jobs. Historically, these completions maintain the capability of regularly monitoring wellhead annulus pressure so that appropriate action can be taken should a leak be detected. In the past, subsea completions have been oil producers, however, gas production, extreme reservoir pressures, and deeper waters are becoming common place. Although subsea wellhead technology and reliability have significantly improved with the introduction of the metal-to-metal sealing system, the potential for annulus pressure buildup still exists. Up to the present, the ability to monitor pressure beyond the first casing string has been virtually non-existent. This paper describes the design, development, testing, and application of non intrusive sensor technology for pressure measurement in subsea wellheads and production trees. The data and test results define and describe the phenomenon of ``inverse magnetostriction``. This phenomenon allows magnetic sensors to non intrusively penetrate three to four inches of steel in a subsea wellhead housing and measure annulus pressure from less than 30 psi to more than 15,000 psi. In addition, test data, charts, and graphs illustrate the sensor`s capability of differentiating between pressure, tension, compression, and bending stress imposed on the wellhead. The electronic interface description details how the data is obtained from the sensors, stored, and later transmitted to existing control systems or to the user interface at the surface via an ROV.

  5. Non-intrusive measurements of frictional forces between micro-spheres and flat surfaces

    NASA Astrophysics Data System (ADS)

    Lin, Wei-Hsun; Daraio, Chiara; Daraio's Group Team

    2014-03-01

    We report a novel, optical pump-probe experimental setup to study micro-friction phenomena between micro-particles and a flat surface. We present a case study of stainless steel microspheres, of diameter near 250 μm, in contact with different surfaces of variable roughness. In these experiments, the contact area between the particles and the substrates is only a few nanometers wide. To excite the particles, we deliver an impulse using a pulsed, high-power laser. The reaction force resulting from the surface ablation induced by the laser imparts a controlled initial velocity to the target particle. This initial velocity can be varied between 10-5 to 1 m/s. We investigate the vibrating and rolling motions of the micro-particles by detecting their velocity and displacement with a laser vibrometer and a high-speed microscope camera. We calculate the effective Hamaker constant from the vibrating motion of a particle, and study its relation to the substrate's surface roughness. We analyze the relation between rolling friction and the minimum momentum required to break surface bonding forces. This non-contact and non-intrusive technique could be employed to study a variety of contact and tribology problems at the microscale.

  6. Assessing Human Activity in Elderly People Using Non-Intrusive Load Monitoring

    PubMed Central

    Alcalá, José M.; Ureña, Jesús; Hernández, Álvaro; Gualda, David

    2017-01-01

    The ageing of the population, and their increasing wish of living independently, are motivating the development of welfare and healthcare models. Existing approaches based on the direct heath-monitoring using body sensor networks (BSN) are precise and accurate. Nonetheless, their intrusiveness causes non-acceptance. New approaches seek the indirect monitoring through monitoring activities of daily living (ADLs), which proves to be a suitable solution. ADL monitoring systems use many heterogeneous sensors, are less intrusive, and are less expensive than BSN, however, the deployment and maintenance of wireless sensor networks (WSN) prevent them from a widespread acceptance. In this work, a novel technique to monitor the human activity, based on non-intrusive load monitoring (NILM), is presented. The proposal uses only smart meter data, which leads to minimum intrusiveness and a potential massive deployment at minimal cost. This could be the key to develop sustainable healthcare models for smart homes, capable of complying with the elderly people’ demands. This study also uses the Dempster-Shafer theory to provide a daily score of normality with regard to the regular behavior. This approach has been evaluated using real datasets and, additionally, a benchmarking against a Gaussian mixture model approach is presented. PMID:28208672

  7. Contextualising Water Use in Residential Settings: A Survey of Non-Intrusive Techniques and Approaches

    PubMed Central

    Carboni, Davide; Gluhak, Alex; McCann, Julie A.; Beach, Thomas H.

    2016-01-01

    Water monitoring in households is important to ensure the sustainability of fresh water reserves on our planet. It provides stakeholders with the statistics required to formulate optimal strategies in residential water management. However, this should not be prohibitive and appliance-level water monitoring cannot practically be achieved by deploying sensors on every faucet or water-consuming device of interest due to the higher hardware costs and complexity, not to mention the risk of accidental leakages that can derive from the extra plumbing needed. Machine learning and data mining techniques are promising techniques to analyse monitored data to obtain non-intrusive water usage disaggregation. This is because they can discern water usage from the aggregated data acquired from a single point of observation. This paper provides an overview of water usage disaggregation systems and related techniques adopted for water event classification. The state-of-the art of algorithms and testbeds used for fixture recognition are reviewed and a discussion on the prominent challenges and future research are also included. PMID:27213397

  8. Experiments using non-intrusive particle tracing techniques for granular chute flows. Final report

    SciTech Connect

    Rosato, A.D.; Dave, R.N.; Fischer, I.S.

    1998-12-31

    The objective of this contract was to develop a system capable of non-intrusively tracking the motion of an individual particle for the study of granular flows down inclined chutes. The result of the project is a system capable of following the three-dimensional translational and rotational motion of an individual particle embedded with a flowing granular material. The basic system consists of a sphere embedded with three orthogonal transmitters emitting at different frequencies which induce voltages in an antenna array surrounding the flow regime. Analysis of the induced voltage signals within the framework of a derived model yields both the position and orientation of the sphere. Tests were performed in a small scale model chute as well as in a cylindrical vibrated granular bed, which clearly demonstrates the capability of the system. As a result of discussions at meetings held semi-annually for the Granular Flow Advanced Research Objectives (GFARO) contractors, it was deemed necessary to pursue an additional experimental program as part of this contract related to the measurement of sphere collision properties. The outcome of the work (reported in Appendix C) is the determination of certain properties which are needed for use in computer simulations and theory.

  9. New Non-Intrusive Inspection Technologies for Nuclear Security and Nonproliferation

    NASA Astrophysics Data System (ADS)

    Ledoux, Robert J.

    2015-10-01

    Comprehensive monitoring of the supply chain for nuclear materials has historically been hampered by non-intrusive inspection systems that have such large false alarm rates that they are impractical in the flow of commerce. Passport Systems, Inc. (Passport) has developed an active interrogation system which detects fissionable material, high Z material, and other contraband in land, sea and air cargo. Passport's design utilizes several detection modalities including high resolution imaging, passive radiation detection, effective-Z (EZ-3D™) anomaly detection, Prompt Neutrons from Photofission (PNPF), and Nuclear Resonance Fluorescence (NRF) isotopic identification. These technologies combine to: detect fissionable, high-Z, radioactive and contraband materials, differentiate fissionable materials from high-Z shielding materials, and isotopically identify actinides, Special Nuclear Materials (SNM), and other contraband (e.g. explosives, drugs, nerve agents). Passport's system generates a 3-D image of the scanned object which contains information such as effective-Z and density, as well as a 2-D image and isotopic and fissionable information for regions of interest.

  10. [INVITED] Non-intrusive optical imaging of face to probe physiological traits in Autism Spectrum Disorder

    NASA Astrophysics Data System (ADS)

    Samad, Manar D.; Bobzien, Jonna L.; Harrington, John W.; Iftekharuddin, Khan M.

    2016-03-01

    Autism Spectrum Disorders (ASD) can impair non-verbal communication including the variety and extent of facial expressions in social and interpersonal communication. These impairments may appear as differential traits in the physiology of facial muscles of an individual with ASD when compared to a typically developing individual. The differential traits in the facial expressions as shown by facial muscle-specific changes (also known as 'facial oddity' for subjects with ASD) may be measured visually. However, this mode of measurement may not discern the subtlety in facial oddity distinctive to ASD. Earlier studies have used intrusive electrophysiological sensors on the facial skin to gauge facial muscle actions from quantitative physiological data. This study demonstrates, for the first time in the literature, novel quantitative measures for facial oddity recognition using non-intrusive facial imaging sensors such as video and 3D optical cameras. An Institutional Review Board (IRB) approved that pilot study has been conducted on a group of individuals consisting of eight participants with ASD and eight typically developing participants in a control group to capture their facial images in response to visual stimuli. The proposed computational techniques and statistical analyses reveal higher mean of actions in the facial muscles of the ASD group versus the control group. The facial muscle-specific evaluation reveals intense yet asymmetric facial responses as facial oddity in participants with ASD. This finding about the facial oddity may objectively define measurable differential markers in the facial expressions of individuals with ASD.

  11. TAD2: the first truly non-intrusive lie detection system deployed in real crime cases

    NASA Astrophysics Data System (ADS)

    Sumriddetchkajorn, Sarun; Somboonkaew, Armote

    2010-11-01

    Interrogation is an important step for seeking truth from the suspect. With the limit of the intrusive nature of the current polygraph, we show here a highly-sought-after non-intrusive lie detection system with a user-friendly interface called TAD2. The key idea behind our TAD2 is based on the analysis of far-infrared data obtained remotely from the periorbital and nostril areas of the suspect during the interrogation. In this way, measured change in skin temperature around two periorbital areas is converted to a relative blood flow velocity while a respiration pattern is simultaneously determined from the measured change in temperature around the nostril region. In addition, TAD2 is embedded with our automatic baseline assignment that is used for distinguishing the subject's response into normal or abnormal stage. In our TAD2, the officer can choose to perform one of the three standard lie detection tests, namely, a modified zone comparison test, a modified general question test, and an irrelevant & relevant test. Field test results from suspects in real crime cases are discussed.

  12. Contextualising Water Use in Residential Settings: A Survey of Non-Intrusive Techniques and Approaches.

    PubMed

    Carboni, Davide; Gluhak, Alex; McCann, Julie A; Beach, Thomas H

    2016-05-20

    Water monitoring in households is important to ensure the sustainability of fresh water reserves on our planet. It provides stakeholders with the statistics required to formulate optimal strategies in residential water management. However, this should not be prohibitive and appliance-level water monitoring cannot practically be achieved by deploying sensors on every faucet or water-consuming device of interest due to the higher hardware costs and complexity, not to mention the risk of accidental leakages that can derive from the extra plumbing needed. Machine learning and data mining techniques are promising techniques to analyse monitored data to obtain non-intrusive water usage disaggregation. This is because they can discern water usage from the aggregated data acquired from a single point of observation. This paper provides an overview of water usage disaggregation systems and related techniques adopted for water event classification. The state-of-the art of algorithms and testbeds used for fixture recognition are reviewed and a discussion on the prominent challenges and future research are also included.

  13. PELAN for non-intrusive inspection of ordnance, containers, and vehicles

    NASA Astrophysics Data System (ADS)

    Holslin, Daniel T.; Shyu, Chaur-Ming; Sullivan, Robert A.; Vourvopoulos, George

    2006-05-01

    When neutrons interact with nuclei, the resulting energy of the interaction can be released in the form of gamma rays, whose energy is characteristic of the nucleus involved in the reaction. The PELAN (Pulsed Elemental Analysis with Neutrons) system uses a pulsed neutron generator and an integral thermalizing shield that induce reactions that cover most of the entire neutron energy range. The neutron generator uses a d-T reaction, which releases fast 14 MeV neutrons responsible for providing information on chemical elements such as C, N, and O. During the time period between pulses, the fast neutrons undergo multiple elastic and inelastic interactions that lower their energy making them easier to be captured by chemical elements, such as H and Cl. The PELAN system has been used for a number of applications where non-intrusive, non-destructive interrogation is needed. This report illustrates examples of its performance in interrogations for unexploded ordnance (UXO), landmines, large vehicle bombs and illicit drug detection.

  14. Non-intrusive detection of methanol in gas phase using infrared degenerate four-wave mixing

    NASA Astrophysics Data System (ADS)

    Zhou, J.; Sahlberg, A. L.; Nilsson, H.; Lundgren, E.; Zetterberg, J.

    2015-11-01

    Sensitive and non-intrusive detection of gas-phase methanol with high spatial and temporal resolution has for the first time been reported using mid-infrared degenerate four-wave mixing (IR-DFWM). IR-DFWM spectra of methanol have been successfully recorded in nitrogen-diluted gas flows at room temperature and at 300 °C, by probing ro-vibrational transitions belonging to the fundamental C-H stretching modes, ν 2 and ν 9, and the O-H stretching mode, ν 1. The detection limit of methanol vapor at room temperature and atmospheric pressure is estimated to be 250 ppm with the present setup. Potential interference from CH4 and CO2 is discussed from recorded IR-DFWM spectra of CH4 and CO2, and it was found that detection of methanol free from CH4 and CO2 interference is possible. These results show the potential of the detection of methanol with IR-DFWM for applications in both combustion and catalytic environments, such as CO2 hydrogenation and CH4 oxidation.

  15. Non-intrusive telemetry applications in the oilsands: from visible light and x-ray video to acoustic imaging and spectroscopy

    NASA Astrophysics Data System (ADS)

    Shaw, John M.

    2013-06-01

    While the production, transport and refining of oils from the oilsands of Alberta, and comparable resources elsewhere is performed at industrial scales, numerous technical and technological challenges and opportunities persist due to the ill defined nature of the resource. For example, bitumen and heavy oil comprise multiple bulk phases, self-organizing constituents at the microscale (liquid crystals) and the nano scale. There are no quantitative measures available at the molecular level. Non-intrusive telemetry is providing promising paths toward solutions, be they enabling technologies targeting process design, development or optimization, or more prosaic process control or process monitoring applications. Operation examples include automated large object and poor quality ore during mining, and monitoring the thickness and location of oil water interfacial zones within separation vessels. These applications involve real-time video image processing. X-ray transmission video imaging is used to enumerate organic phases present within a vessel, and to detect individual phase volumes, densities and elemental compositions. This is an enabling technology that provides phase equilibrium and phase composition data for production and refining process development, and fluid property myth debunking. A high-resolution two-dimensional acoustic mapping technique now at the proof of concept stage is expected to provide simultaneous fluid flow and fluid composition data within porous inorganic media. Again this is an enabling technology targeting visualization of diverse oil production process fundamentals at the pore scale. Far infrared spectroscopy coupled with detailed quantum mechanical calculations, may provide characteristic molecular motifs and intermolecular association data required for fluid characterization and process modeling. X-ray scattering (SAXS/WAXS/USAXS) provides characteristic supramolecular structure information that impacts fluid rheology and process

  16. Non-intrusive schemes for speed and axle identification in bridge-weigh-in-motion systems

    NASA Astrophysics Data System (ADS)

    Kalhori, Hamed; Makki Alamdari, Mehrisadat; Zhu, Xinqun; Samali, Bijan; Mustapha, Samir

    2017-02-01

    Bridge weigh-in-motion (BWIM) is an approach through which the axle and gross weight of trucks travelling at normal highway speed are identified using the response of an instrumented bridge. The vehicle speed, the number of axles, and the axle spacing are crucial parameters, and are required to be determined in the majority of BWIM algorithms. Nothing-on-the-road (NOR) strategy suggests using the strain signals measured at some particular positions underneath the deck or girders of a bridge to obtain this information. The objective of this research is to present a concise overview of the challenges of the current non-intrusive schemes for speed and axle determination through bending-strain and shear-strain based approaches. The problem associated with the global bending-strain responses measured at quarter points of span is discussed and a new sensor arrangement is proposed as an alternative. As for measurement of local responses rather than the global responses, the advantage of shear strains over bending strains is presented. However, it is illustrated that shear strains at quarter points of span can only provide accurate speed estimation but fail to detect the correct number of axles. As a remedy, it is demonstrated that, even for closely-spaced axles, the shear strain at the beginning of the bridge is capable of reliably identifying the number of axles. In order to provide a fully automated speed and axle identification system, appropriate signal processing including low-pass filtering and wavelet transforms are applied to the raw time signals. As case studies, the results of experimental testing in laboratory and on a real bridge are presented.

  17. Non-intrusive measurements of transitional and turbulent convective heat transfer in a rectangular microchannel

    NASA Astrophysics Data System (ADS)

    Natrajan, V. K.; Christensen, K. T.

    2011-08-01

    The thermal-transport characteristics of transitional and turbulent flow through smooth- and rough-wall rectangular microchannels (Dh = 600 μm) under constant-heat-flux conditions at three of the four walls were investigated by performing non-intrusive and spatially resolved measurements of fluid temperature via two-color fluorescent thermometry. These measurements, along with bulk pressure-drop measurements, were performed over the Reynolds-number range 1300\\le {\\emph {Re}} \\le 5200. The pressure-drop results revealed the onset of transition above {\\emph {Re}_{cr}}\\cong 1800 for the smooth-wall case, consistent with the onset of transition at the macroscale. However, with increasing surface roughness, deviation from laminar behavior was noted at progressively lower Re which indicates that {\\emph {Re}_{cr}} is a function of roughness. Mean temperature profiles calculated from data sets acquired in the transitional regime for the smooth- and rough-wall cases illustrated deviation from fully developed laminar behavior for {\\emph {Re} \\gt \\emph {Re}_{cr}}. Nevertheless, these profiles still suggest similarities in the transitional pathway of the thermal-transport behavior for the smooth and rough cases save for a relative shift due to the onset of transition at lower Re with increasing surface roughness. Estimates of the bulk Nusselt number indicated enhancement in thermal transport over the smooth-wall case with increasing surface roughness in both the transitional and turbulent regimes, though the smooth-wall data agreed well with macroscale predictions over the range of turbulent Re considered. While the shift in the transitional pathway of the thermal transport behavior toward lower Re accounts for a portion of this enhancement, an increase in turbulent convection with increasing surface roughness might also contribute in this regard.

  18. Cosmic Rays to Acoustics: Non-intrusive Monitoring for Nuclear Applications

    SciTech Connect

    Stanley, S.J.; Scully, P.

    2007-07-01

    The radioactive nature of the material handled during nuclear reprocessing or fuel manufacture often makes both process monitoring and process diagnostics most challenging. Fox example, quantifying material inside a radiation shielded storage vessel, locating sediment layers and the associated interfaces represents a difficult challenge. Alternatively, measuring the extent of sludge re-suspension and quantifying the amounts of sludge transferred during a sludge movement campaign also represents a re-occurring problem. Remote non-invasive process monitoring and imaging techniques are most applicable in the nuclear sector as they provide a means to monitor or image the given process, container or vessel allowing a remote interrogation whilst reducing operator dosage uptake. A number of currently used types of non-intrusive process monitoring and imaging techniques are discussed in this paper, each with their associated applications. Firstly, the use of (very) high energy naturally occurring cosmic ray muons for imaging the internal contents of large or radiation shielded vessels is discussed. Secondly, the use of non-invasive acoustic monitoring techniques to detect the presence of a gas-core inside a stirred vessel as well as the detection of flowing solids is described. Finally, the use of electrical resistance tomography for imaging the ease of sludge re-suspension in a storage vessel is also discussed. Within the UK Nuclear Sector, the use of non-invasive imaging and process monitoring techniques in recent years has shown a marked increase. Being able to 'see inside' the process represents a powerful tool allowing the quantification, location and characterisation of material whilst increasing the overall understanding of the given process providing significant safety, economical and operational benefits. (authors)

  19. Waste Characterization Methods

    SciTech Connect

    Vigil-Holterman, Luciana R.; Naranjo, Felicia Danielle

    2016-02-02

    This report discusses ways to classify waste as outlined by LANL. Waste Generators must make a waste determination and characterize regulated waste by appropriate analytical testing or use of acceptable knowledge (AK). Use of AK for characterization requires several source documents. Waste characterization documentation must be accurate, sufficient, and current (i.e., updated); relevant and traceable to the waste stream’s generation, characterization, and management; and not merely a list of information sources.

  20. Predicting the intelligibility of reverberant speech for cochlear implant listeners with a non-intrusive intelligibility measure.

    PubMed

    Chen, Fei; Hazrati, Oldooz; Loizou, Philipos C

    2013-05-01

    Reverberation is known to reduce the temporal envelope modulations present in the signal and affect the shape of the modulation spectrum. A non-intrusive intelligibility measure for reverberant speech is proposed motivated by the fact that the area of the modulation spectrum decreases with increasing reverberation. The proposed measure is based on the average modulation area computed across four acoustic frequency bands spanning the signal bandwidth. High correlations (r = 0.98) were observed with sentence intelligibility scores obtained by cochlear implant listeners. Proposed measure outperformed other measures including an intrusive speech-transmission index based measure.

  1. Predicting the intelligibility of reverberant speech for cochlear implant listeners with a non-intrusive intelligibility measure

    PubMed Central

    Chen, Fei; Hazrati, Oldooz; Loizou, Philipos C.

    2012-01-01

    Reverberation is known to reduce the temporal envelope modulations present in the signal and affect the shape of the modulation spectrum. A non-intrusive intelligibility measure for reverberant speech is proposed motivated by the fact that the area of the modulation spectrum decreases with increasing reverberation. The proposed measure is based on the average modulation area computed across four acoustic frequency bands spanning the signal bandwidth. High correlations (r = 0.98) were observed with sentence intelligibility scores obtained by cochlear implant listeners. Proposed measure outperformed other measures including an intrusive speech-transmission index based measure. PMID:23710246

  2. Characterization Methods of Encapsulates

    NASA Astrophysics Data System (ADS)

    Zhang, Zhibing; Law, Daniel; Lian, Guoping

    , reliable methods which can be used to characterize these properties of encapsulates are vital. In this chapter, the state-of-art of these methods, their principles and applications, and release mechanisms are described as follows.

  3. Characterization of electrical appliances based on their immitance

    NASA Astrophysics Data System (ADS)

    Wójcik, Augustyn; Winiecki, Wiesław; Kowalik, Ryszard

    2016-09-01

    The article contains an overview of electrical devices parameters employed in non-intrusive load monitoring system. Most frequently used parameters of household appliances, based on current and power supply voltage waveforms, are presented. On the basis of performed experiments, the impact of the load on the pattern parameters is demonstrated. The new method for characterization of electrical devices based on their immitance parameters is proposed. The new set of parameters, calculated with the use of designed method and evaluated, is discussed.

  4. Investigation of non-premixed flame combustion characters in GO2/GH2 shear coaxial injectors using non-intrusive optical diagnostics

    NASA Astrophysics Data System (ADS)

    Dai, Jian; Yu, NanJia; Cai, GuoBiao

    2015-12-01

    Single-element combustor experiments are conducted for three shear coaxial geometry configuration injectors by using gaseous oxygen and gaseous hydrogen (GO2/GH2) as propellants. During the combustion process, several spatially and timeresolved non-intrusive optical techniques, such as OH planar laser induced fluorescence (PLIF), high speed imaging, and infrared imaging, are simultaneously employed to observe the OH radical concentration distribution, flame fluctuations, and temperature fields. The results demonstrate that the turbulent flow phenomenon of non-premixed flame exhibits a remarkable periodicity, and the mixing ratio becomes a crucial factor to influence the combustion flame length. The high speed and infrared images have a consistent temperature field trend. As for the OH-PLIF images, an intuitionistic local flame structure is revealed by single-shot instantaneous images. Furthermore, the means and standard deviations of OH radical intensity are acquired to provide statistical information regarding the flame, which may be helpful for validation of numerical simulations in future. Parameters of structure configurations, such as impinging angle and oxygen post thickness, play an important role in the reaction zone distribution. Based on a successful flame contour extraction method assembled with non-linear anisotropic diffusive filtering and variational level-set, it is possible to implement a fractal analysis to describe the fractal characteristics of the non-premixed flame contour. As a result, the flame front cannot be regarded as a fractal object. However, this turbulent process presents a self-similarity characteristic.

  5. Non-Intrusive Sensor for In-Situ Measurement of Recession Rate of Ablative and Eroding Materials

    NASA Technical Reports Server (NTRS)

    Papadopoulos, George (Inventor); Tiliakos, Nicholas (Inventor); Benel, Gabriel (Inventor); Thomson, Clint (Inventor)

    2014-01-01

    A non-intrusive sensor for in-situ measurement of recession rate of heat shield ablatives. An ultrasonic wave source is carried in the housing. A microphone is also carried in the housing, for collecting the reflected ultrasonic waves from an interface surface of the ablative material. A time phasing control circuit is also included for time-phasing the ultrasonic wave source so that the waves reflected from the interface surface of the ablative material focus on the microphone, to maximize the acoustic pressure detected by the microphone and to mitigate acoustic velocity variation effects through the material through a de-coupling process that involves a software algorithm. A software circuit for computing the location off of which the ultrasonic waves scattered to focus back at the microphone is also included, so that the recession rate of the heat shield ablative may be monitored in real-time through the scan-focus approach.

  6. A system for the non-intrusive detection of damage in underground power cables: Damage modeling and sensor system design

    NASA Astrophysics Data System (ADS)

    Gorgen, Marvin Alexander

    A system for non-intrusive sensing of underground power cable impedance is presented. The impedance sensor is used for the detection of damage to underground power cables. The system is capable of taking measurements without the need to interrupt power service. To isolate the impedance measurement from the effects of customer loading, a blocking unit is proposed which presents an open circuit to the impedance sensor in the transmission line at the point where the blocker is clamped onto the cable. Both of the proposed devices are prototyped and evaluated. The impedance sensor is demonstrated to be capable of accurate impedance measurements within a 2% error over a range from 50 to 1000 Ohms. The blocker is demonstrated to provide approximately 30 dB of attenuation over the designed ranged of measurement frequencies. The system can detect impedance changes resulting from corrosion or damage in underground power cables.

  7. Non-Intrusive Device for Real-Time Circulatory System Assessment with Advanced Signal Processing Capabilities

    NASA Astrophysics Data System (ADS)

    Pinheiro, E.; Postolache, O.; Girão, P.

    2010-01-01

    This paper presents a device that uses three cardiography signals to characterize several important parameters of a subject's circulatory system. Using electrocardiogram, finger photoplethysmogram, and ballistocardiogram, three heart rate estimates are acquired from beat-to-beat time interval extraction. Furthermore, pre-ejection period, pulse transit time (PTT), and pulse arrival time (PAT) are computed, and their long-term evolution is analyzed. The system estimates heart rate variability (HRV) and blood pressure variability (BPV) from the heart rate and PAT time series, to infer the activity of the cardiac autonomic system. The software component of the device evaluates the frequency content of HRV and BPV, and also their fractal dimension and entropy, thus providing a detailed analysis of the time series' regularity and complexity evolution, to allow personalized subject evaluation.

  8. Counting in the dark: non-intrusive laser scanning for population counting and identifying roosting bats.

    PubMed

    Azmy, Suzanna Noor; Sah, Shahrul Anuar Mohd; Shafie, Nur Juliani; Ariffin, Azman; Majid, Zulkepli; Ismail, Muhamad Nor Akmal; Shamsir, Mohd Shahir

    2012-01-01

    Population surveys and species recognition for roosting bats are either based on capture, sight or optical-mechanical count methods. However, these methods are intrusive, are tedious and, at best, provide only statistical estimations. Here, we demonstrated the successful use of a terrestrial Light Detection and Ranging (LIDAR) laser scanner for remotely identifying and determining the exact population of roosting bats in caves. LIDAR accurately captured the 3D features of the roosting bats and their spatial distribution patterns in minimal light. The high-resolution model of the cave enabled an exact count of the visibly differentiated Hipposideros larvatus and their roosting pattern within the 3D topology of the cave. We anticipate that the development of LIDAR will open up new research possibilities by allowing researchers to study roosting behaviour within the topographical context of a cave's internal surface, thus facilitating rigorous quantitative characterisations of cave roosting behaviour.

  9. Non-intrusive beam power monitor for high power pulsed or continuous wave lasers

    DOEpatents

    Hawsey, Robert A.; Scudiere, Matthew B.

    1993-01-01

    A system and method for monitoring the output of a laser is provided in which the output of a photodiode disposed in the cavity of the laser is used to provide a correlated indication of the laser power. The photodiode is disposed out of the laser beam to view the extraneous light generated in the laser cavity whose intensity has been found to be a direct correlation of the laser beam output power level. Further, the system provides means for monitoring the phase of the laser output beam relative to a modulated control signal through the photodiode monitor.

  10. Non-intrusive measurement of hot gas temperature in a gas turbine engine

    DOEpatents

    DeSilva, Upul P.; Claussen, Heiko; Yan, Michelle Xiaohong; Rosca, Justinian; Ulerich, Nancy H.

    2016-09-27

    A method and apparatus for operating a gas turbine engine including determining a temperature of a working gas at a predetermined axial location within the engine. An acoustic signal is encoded with a distinct signature defined by a set of predetermined frequencies transmitted as a non-broadband signal. Acoustic signals are transmitted from an acoustic transmitter located at a predetermined axial location along the flow path of the gas turbine engine. A received signal is compared to one or more transmitted signals to identify a similarity of the received signal to a transmitted signal to identify a transmission time for the received signal. A time-of-flight is determined for the signal and the time-of-flight for the signal is processed to determine a temperature in a region of the predetermined axial location.

  11. Advanced Fine Particulate Characterization Methods

    SciTech Connect

    Steven Benson; Lingbu Kong; Alexander Azenkeng; Jason Laumb; Robert Jensen; Edwin Olson; Jill MacKenzie; A.M. Rokanuzzaman

    2007-01-31

    The characterization and control of emissions from combustion sources are of significant importance in improving local and regional air quality. Such emissions include fine particulate matter, organic carbon compounds, and NO{sub x} and SO{sub 2} gases, along with mercury and other toxic metals. This project involved four activities including Further Development of Analytical Techniques for PM{sub 10} and PM{sub 2.5} Characterization and Source Apportionment and Management, Organic Carbonaceous Particulate and Metal Speciation for Source Apportionment Studies, Quantum Modeling, and High-Potassium Carbon Production with Biomass-Coal Blending. The key accomplishments included the development of improved automated methods to characterize the inorganic and organic components particulate matter. The methods involved the use of scanning electron microscopy and x-ray microanalysis for the inorganic fraction and a combination of extractive methods combined with near-edge x-ray absorption fine structure to characterize the organic fraction. These methods have direction application for source apportionment studies of PM because they provide detailed inorganic analysis along with total organic and elemental carbon (OC/EC) quantification. Quantum modeling using density functional theory (DFT) calculations was used to further elucidate a recently developed mechanistic model for mercury speciation in coal combustion systems and interactions on activated carbon. Reaction energies, enthalpies, free energies and binding energies of Hg species to the prototype molecules were derived from the data obtained in these calculations. Bimolecular rate constants for the various elementary steps in the mechanism have been estimated using the hard-sphere collision theory approximation, and the results seem to indicate that extremely fast kinetics could be involved in these surface reactions. Activated carbon was produced from a blend of lignite coal from the Center Mine in North Dakota and

  12. Damage assessment using advanced non-intrusive inspection methods: integration of space, UAV, GPR, and field spectroscopy

    NASA Astrophysics Data System (ADS)

    Themistocleous, Kyriacos; Neocleous, Kyriacos; Pilakoutas, Kypros; Hadjimitsis, Diofantos G.

    2014-08-01

    The predominant approach for conducting road condition surveys and analyses is still largely based on extensive field observations. However, visual assessment alone cannot identify the actual extent and severity of damage. New non-invasive and cost-effective non-destructive (NDT) remote sensing technologies can be used to monitor road pavements across their life cycle, including remotely sensed aerial and satellite visual and thermal image (AI) data, Unmanned Aerial Vehicles (UAVs), Spectroscopy and Ground Penetrating Radar (GRP). These non-contact techniques can be used to obtain surface and sub-surface information about damage in road pavements, including the crack depth, and in-depth structural failure. Thus, a smart and cost-effective methodology is required that integrates several of these non-destructive/ no-contact techniques for the damage assessment and monitoring at different levels. This paper presents an overview of how an integration of the above technologies can be used to conduct detailed road condition surveys. The proposed approach can also be used to predict the future needs for road maintenance; this information is proven to be valuable to a strategic decision making tools that optimizes maintenance based on resources and environmental issues.

  13. Application and assessment of ultrasonic inspection methods for flaw detection and characterization of manganese steel frogs

    NASA Astrophysics Data System (ADS)

    Cinson, A.; Diaz, A.; Prowant, M.

    2011-04-01

    Ultrasonic nondestructive examination (NDE) has a long and successful history of application across a wide array of industries, including nuclear, aerospace, and transportation sectors. In coarse-grained, cast Manganese (Mn) steel frog components, NDE/inspection challenges are encountered both in-field (after the frogs have been installed on a rail line) and at the manufacturing facilities during post-fabrication QA/QC activities. Periodically inherently flawed frogs are received from a manufacturer, and put into service, as most railroad operators do not have a means to conduct pre-service examinations on received components. Accordingly, there is a need for a pre-service inspection system that can provide a rapid, cost-effective and non-intrusive inspection capability for detection of defects, flaws, and other anomalies in frog components, in order to avoid premature initiation of cracks or failures of these components during service. This study focused on evaluating use of a volumetric phased-array ultrasonic testing (PA-UT) method to monitor fabrication quality assurance. In this preliminary assessment of using PA-UT, data were acquired at a frequency of 2.0 MHz on a known, flawed Mn steel frog component directly from a manufacturing facility. The component contained flaws commonly found as a result of the manufacturing process of these cast rail components. The data were analyzed and the anomalies were detected, localized and characterized. Results were compared against baseline radiographic data. A detection metric was reported in the form of signal-to-noise values.

  14. Evaluation of Electrochemical Methods for Electrolyte Characterization

    NASA Technical Reports Server (NTRS)

    Heidersbach, Robert H.

    2001-01-01

    This report documents summer research efforts in an attempt to develop an electrochemical method of characterizing electrolytes. The ultimate objective of the characterization would be to determine the composition and corrosivity of Martian soil. Results are presented using potentiodynamic scans, Tafel extrapolations, and resistivity tests in a variety of water-based electrolytes.

  15. Application of geophysical methods for fracture characterization

    SciTech Connect

    Lee, K.H.; Majer, E.L.; McEvilly, T.V. |; Morrison, H.F. |

    1990-01-01

    One of the most crucial needs in the design and implementation of an underground waste isolation facility is a reliable method for the detection and characterization of fractures in zones away from boreholes or subsurface workings. Geophysical methods may represent a solution to this problem. If fractures represent anomalies in the elastic properties or conductive properties of the rocks, then the seismic and electrical techniques may be useful in detecting and characterizing fracture properties. 7 refs., 3 figs.

  16. Minimizing Characterization - Derived Waste at the Department of Energy Savannah River Site, Aiken, South Carolina

    SciTech Connect

    Van Pelt, R. S.; Amidon, M. B.; Reboul, S. H.

    2002-02-25

    Environmental restoration activities at the Department of Energy Savannah River Site (SRS) utilize innovative site characterization approaches and technologies that minimize waste generation. Characterization is typically conducted in phases, first by collecting large quantities of inexpensive data, followed by targeted minimally invasive drilling to collect depth-discrete soil/groundwater data, and concluded with the installation of permanent multi-level groundwater monitoring wells. Waste-reducing characterization methods utilize non-traditional drilling practices (sonic drilling), minimally intrusive (geoprobe, cone penetrometer) and non-intrusive (3-D seismic, ground penetration radar, aerial monitoring) investigative tools. Various types of sensor probes (moisture sensors, gamma spectroscopy, Raman spectroscopy, laser induced and X-ray fluorescence) and hydrophobic membranes (FLUTe) are used in conjunction with depth-discrete sampling techniques to obtain high-resolution 3-D plume profiles. Groundwater monitoring (short/long-term) approaches utilize multi-level sampling technologies (Strata-Sampler, Cone-Sipper, Solinst Waterloo, Westbay) and low-cost diffusion samplers for seepline/surface water sampling. Upon collection of soil and groundwater data, information is portrayed in a Geographic Information Systems (GIS) format for interpretation and planning purposes. At the SRS, the use of non-traditional drilling methods and minimally/non intrusive investigation approaches along with in-situ sampling methods has minimized waste generation and improved the effectiveness and efficiency of characterization activities.

  17. A non-intrusive fluid-wave actuator and sensor pair for the active control of fluid-borne vibrations in a pipe

    NASA Astrophysics Data System (ADS)

    Brennan, M. J.; Elliott, S. J.; Pinnington, R. J.

    1996-06-01

    This paper describes the design of a non-intrusive fluid-wave actuator and sensor pair for use in an active control system to control fluid-borne vibrations in pipework systems. Piping systems can be excited by sources such as pumps and compressors and vibrational energy can propagate both in the pipe wall and the fluid. The transducers developed in this paper are designed only for the control of the fluid-borne vibrational energy. A theoretical framework is developed that integrates the transducers into the pipe and couples them to the motion of the fluid inside the pipe. A hydraulic actuator driven with a magnetostrictive element and fitted to a water-filled perspex pipe has been designed and tested. The sensor was made from piezoelectric elements fitted around the outer circumference of the pipe. Experimental results show that the actuator is capable of suppressing a propagating fluid-wave, but in doing so it increases the vibration of the pipe-wall in the vicinity of the actuator. When the sensor is employed as an error sensor together with the actuator in the frequency range 10 - 1000 Hz, a reduction in the fluid-wave amplitude of around 20 dB is possible.

  18. Combustion behaviors of GO2/GH2 swirl-coaxial injector using non-intrusive optical diagnostics

    NASA Astrophysics Data System (ADS)

    GuoBiao, Cai; Jian, Dai; Yang, Zhang; NanJia, Yu

    2016-06-01

    This research evaluates the combustion behaviors of a single-element, swirl-coaxial injector in an atmospheric combustion chamber with gaseous oxygen and gaseous hydrogen (GO2/GH2) as the propellants. A brief simulated flow field schematic comparison between a shear-coaxial injector and the swirl-coaxial injector reveals the distribution characteristics of the temperature field and streamline patterns. Advanced optical diagnostics, i.e., OH planar laser-induced fluorescence and high-speed imaging, are simultaneously employed to determine the OH radical spatial distribution and flame fluctuations, respectively. The present study focuses on the flame structures under varying O/F mixing ratios and center oxygen swirl intensities. The combined use of several image-processing methods aimed at OH instantaneous images, including time-averaged, root-mean-square, and gradient transformation, provides detailed information regarding the distribution of the flow field. The results indicate that the shear layers anchored on the oxygen injector lip are the main zones of chemical heat release and that the O/F mixing ratio significantly affects the flame shape. Furthermore, with high-speed imaging, an intuitionistic ignition process and several consecutive steady-state images reveal that lean conditions make it easy to drive the combustion instabilities and that the center swirl intensity has a moderate influence on the flame oscillation strength. The results of this study provide a visualized analysis for future optimal swirl-coaxial injector designs.

  19. Non-Intrusive Cable Tester

    NASA Technical Reports Server (NTRS)

    Medelius, Pedro J. (Inventor); Simpson, Howard J. (Inventor)

    1999-01-01

    A cable tester is described for low frequency testing of a cable for faults. The tester allows for testing a cable beyond a point where a signal conditioner is installed, minimizing the number of connections which have to be disconnected. A magnetic pickup coil is described for detecting a test signal injected into the cable. A narrow bandpass filter is described for increasing detection of the test signal. The bandpass filter reduces noise so that a high gain amplifier provided for detecting a test signal is not completely saturate by noise. To further increase the accuracy of the cable tester, processing gain is achieved by comparing the signal from the amplifier with at least one reference signal emulating the low frequency input signal injected into the cable. Different processing techniques are described evaluating a detected signal.

  20. Enhanced damage characterization using wavefield imaging methods

    NASA Astrophysics Data System (ADS)

    Blackshire, James L.

    2017-02-01

    Wavefield imaging methods are becoming a popular tool for characterizing and studying elastic field interactions in a wide variety of material systems. By using a scanning laser vibrometry detection system, the transient displacement fields generated by an ultrasonic source can be visualized and studied in detail. As a tool for quantitative nondestructive evaluation, the visualization of elastic waves provides a unique opportunity for understanding the scattering of elastic waves from insipient damage, where the detection and characterization of damage features using ultrasound can be enhanced in many instances. In the present effort, the detection and direct imaging of fatigue cracks in metals, and delaminations in composites, is described. An examination of the transient displacement fields near the scattering sites show additional details related to the local damage morphology, which can be difficult to account for using traditional far-field NDE sensing methods. A combination of forward models and experimental wavefield imaging methods were used to explore enhancement opportunities for the full 3-dimensional characterization of surface-breaking cracks and delaminations.

  1. Characterization methods for ultrasonic test systems

    SciTech Connect

    Busse, L.J.; Becker, F.L.; Bowey, R.E.; Doctor, S.R.; Gribble, R.P.; Posakony, G.J.

    1982-07-01

    Methods for the characterization of ultrasonic transducers (search units) and instruments are presented. The instrument system is considered as three separate components consisting of a transducer, a receiver-display, and a pulser. The operation of each component is assessed independently. The methods presented were chosen because they provide the greatest amount of information about component operation and were not chosen based upon such conditions as cost, ease of operation, field implementation, etc. The results of evaluating a number of commercially available ultrasonic test instruments are presented.

  2. Application of the optical flow method for the experimental analysis of turbulent flame propagation in a transparent engine

    NASA Astrophysics Data System (ADS)

    Barone, Mario; Lombardi, Simone; Continillo, Gaetano; Sementa, Paolo; Vaglieco, Bianca Maria

    2016-12-01

    This paper illustrates the analysis conducted on high-definition, high sampling rate image sequences collected in experiments with a single spark ignition optically accessible engine. Images are first processed to identify the reaction front, and then analyzed by an optical flow estimation technique. The results show that each velocity component of the estimated flow field has an ECDF very similar to the CDF of a Gaussian distribution, whereas the velocity magnitude has an ECDF well fitted by a Rayleigh probability distribution. The proposed non-intrusive method provides a fast statistical characterization of the flame propagation phenomenon in the engine combustion chamber.

  3. Method Of Characterizing An Electrode Binder

    DOEpatents

    Cocciantelli, Jean-Michel; Coco, Isabelle; Villenave, Jean-Jacques

    1999-05-11

    In a method of characterizing a polymer binder for cell electrodes in contact with an electrolyte and including a current collector and a paste containing an electrochemically active material and said binder, a spreading coefficient of the binder on the active material is calculated from the measured angle of contact between standard liquids and the active material and the binder, respectively. An interaction energy of the binder with the electrolyte is calculated from the measured angle of contact between the electrolyte and the binder. The binder is selected such that the spreading coefficient is less than zero and the interaction energy is at least 60 mJ/m.sup.2.

  4. Automated Weld Characterization Using the Thermoelectric Method

    NASA Technical Reports Server (NTRS)

    Fulton, J. P.; Wincheski, B.; Namkung, M.

    1992-01-01

    The effective assessment of the integrity of welds is a complicated NDE problem that continues to be a challenge. To be able to completely characterize a weld, detailed knowledge of its tensile strength, ductility, hardness, microstructure, macrostructure, and chemical composition is needed. NDE techniques which can provide information on any of these features are extremely important. In this paper, we examine a seldom used approach based on the thermoelectric (TE) effect for characterizing welds and their associated heat affected zone (HAZ). The thermoelectric method monitors the thermoelectric power which is sensitive to small changes in the kinetics of the conduction electrons near the Fermi surface that can be caused by changes in the local microstructure. The technique has been applied to metal sorting, quality testing, flaw detection, thickness gauging of layers, and microscopic structural analysis. To demonstrate the effectiveness of the technique for characterizing welds, a series of tungsten-inert-gas welded Inconel-718 samples were scanned with a computer controlled TE probe. The samples were then analyzed using a scanning electron microscope and Rockwell hardness tests to characterize the weld and the associated HAZ. We then correlated the results with the TE measurements to provide quantitative information on the size of the HAZ and the degree of hardness of the material in the weld region. This provides potentially valuable information on the strength and fatigue life of the weld. We begin the paper by providing a brief review of the TE technique and then highlight some of the factors that can effect the measurements. Next, we provide an overview of the experimental procedure and discuss the results. Finally, we summarize our findings and consider areas for future research.

  5. Polylactides-Methods of synthesis and characterization.

    PubMed

    Pretula, Julia; Slomkowski, Stanislaw; Penczek, Stanislaw

    2016-12-15

    Polylactides with various molar masses, microstructures and crystallinities are used as degradable and biocompatible polymers suitable for preparation of drug carriers and temporary medical implants. This paper presents state of current knowledge on synthesis of lactic acids, high purity lactide monomers and their polymerization. Syntheses of high molar mass polylactides by polycondensation of lactic acid and by ring-opening polymerization of lactides are described and their advantages and disadvantages are discussed. Mechanisms of lactide polymerization initiated by metal alkoxides are described. There are presented also results of more recent studies of polymerization initiated with the so-called "no metal" organocatalysts; both anionic and cationic. Presented are advantages and limitations of synthesis of PLA by all the major polymerization processes until now. Some properties of PLA and most important methods used for PLA characterization are also described.

  6. Smart Optical Material Characterization System and Method

    NASA Technical Reports Server (NTRS)

    Choi, Sang Hyouk (Inventor); Park, Yeonjoon (Inventor)

    2015-01-01

    Disclosed is a system and method for characterizing optical materials, using steps and equipment for generating a coherent laser light, filtering the light to remove high order spatial components, collecting the filtered light and forming a parallel light beam, splitting the parallel beam into a first direction and a second direction wherein the parallel beam travelling in the second direction travels toward the material sample so that the parallel beam passes through the sample, applying various physical quantities to the sample, reflecting the beam travelling in the first direction to produce a first reflected beam, reflecting the beam that passes through the sample to produce a second reflected beam that travels back through the sample, combining the second reflected beam after it travels back though the sample with the first reflected beam, sensing the light beam produced by combining the first and second reflected beams, and processing the sensed beam to determine sample characteristics and properties.

  7. Frequency-Domain Methods for Characterization of Pulsed Power Diagnostics

    SciTech Connect

    White, A D; Anderson, R A; Ferriera, T J; Goerz, D A

    2009-07-27

    This paper discusses methods of frequency-domain characterization of pulsed power sensors using vector network analyzer and spectrum analyzer techniques that offer significant simplification over time-domain methods, while mitigating or minimizing the effect of the difficulties present in time domain characterization. These methods are applicable to characterization of a wide variety of sensors.

  8. Spectral Analysis of Surface Waves and Standard Penetration Test for Sub-Soil Characterization: A Comparison Study.

    NASA Astrophysics Data System (ADS)

    Villagomez, Jessica

    2016-04-01

    Spectral Analysis of Surface Waves (SASW) is a method used for sub-soil characterization. SASW has the advantage of being non-intrusive and non-invasive. Commonly used in current geotechnical engineering for being faster and cheaper than other laboratory tests. Standard Penetration test (SPT), which is used to obtain stratigraphic profiles of the sub-soil, contrary to SASW test, is invasive, destructive and not less important, expensive. The SASW method uses dispersive characteristics of Rayleigh waves in stratified or half-space media to obtain their physical parameters and henceforward its characterization. From this, a soil profile is estimated. A comparison between a geophysical method, Spectral Analysis of Surface Waves (SASW), and the N-value obtained from a classic geotechnical test (SPT) to estimate and characterize the in-site sub-soil properties at Patillas Dam, Puerto Rico, will be given in this work.

  9. Marine electromagnetic methods for gas hydrate characterization

    NASA Astrophysics Data System (ADS)

    Weitemeyer, Karen Andrea

    Gas hydrate is a type of clathrate consisting of a gas molecule (usually methane) encased in a water lattice, and is found worldwide in marine and permafrost regions. Hydrate is important because it is a geo-hazard, has potential as an energy resource, and is a possible contributor to climate change. There are large uncertainties about the global amount of hydrate present, partly because the characterization of hydrate with seismic methods is unreliable. Marine electromagnetic (EM) methods can be used to image the bulk resistivity structure of the subsurface and are able to augment seismic data to provide valuable information about gas hydrate distribution in the marine environment. Marine controlled source electromagnetic (CSEM) sounding data from a pilot survey at Hydrate Ridge, located on the Cascadia subduction zone, show that regions with higher concentrations of hydrate are resistive. The apparent resistivities computed from the CSEM data are consistent for both apparent resistivity pseudosections and two-dimensional regularized inversion results. The 2D inversion results provide evidence of a strong resistor near the seismic bottom simulating reflector (BSR), and geologic structures are imaged to about a kilometer depth. Comparisons with electrical resistivity logging while drilling (LWD) data from Ocean Drilling Program Leg 204 show a general agreement except for one of three sites where the CSEM inversion shows a large resistor at depth as compared to the LWD. An overlay of the CSEM inversion with a collocated seismic line 230 from Trehu et al. (2001) exhibits remarkable similarities with the sedimentary layering, geologic structures, and the seismic BSR. Magnetotelluric (MT) sounding data collected simultaneously during the CSEM survey provide an electrical image of the oceanic crust and mantle (50 km depth) and the folding associated with the accretionary complex (top 2 km depth). In addition, the MT model provides a complementary low-resolution image of

  10. DETECTION OF HISTORICAL PIPELINE LEAK PLUMES USING NON-INTRUSIVE SURFACE-BASED GEOPHYSICAL TECHNIQUES AT THE HANFORD NUCLEAR SITE WASHINGTON USA

    SciTech Connect

    SKORSKA MB; FINK JB; RUCKER DF; LEVITT MT

    2010-12-02

    Historical records from the Department of Energy Hanford Nuclear Reservation (in eastern WA) indicate that ruptures in buried waste transfer pipelines were common between the 1940s and 1980s, which resulted in unplanned releases (UPRs) of tank: waste at numerous locations. A number of methods are commercially available for the detection of active or recent leaks, however, there are no methods available for the detection of leaks that occurred many years ago. Over the decades, leaks from the Hanford pipelines were detected by visual observation of fluid on the surface, mass balance calculations (where flow volumes were monitored), and incidental encounters with waste during excavation or drilling. Since these detection methods for historic leaks are so limited in resolution and effectiveness, it is likely that a significant number of pipeline leaks have not been detected. Therefore, a technology was needed to detect the specific location of unknown pipeline leaks so that characterization technologies can be used to identify any risks to groundwater caused by waste released into the vadose zone. A proof-of-concept electromagnetic geophysical survey was conducted at an UPR in order to image a historical leak from a waste transfer pipeline. The survey was designed to test an innovative electromagnetic geophysical technique that could be used to rapidly map the extent of historical leaks from pipelines within the Hanford Site complex. This proof-of-concept test included comprehensive testing and analysis of the transient electromagnetic method (TEM) and made use of supporting and confirmatory geophysical methods including ground penetrating radar, magnetics, and electrical resistivity characterization (ERC). The results for this initial proof-of-concept test were successful and greatly exceeded the expectations of the project team by providing excellent discrimination of soils contaminated with leaked waste despite the interference from an electrically conductive pipe.

  11. A novel P700 redox kinetics probe for rapid, non-intrusive and whole-tissue determination of photosystem II functionality, and the stoichiometry of the two photosystems in vivo.

    PubMed

    Jia, Husen; Dwyer, Simon A; Fan, Da-Yong; Han, Yaqin; Badger, Murray R; von Caemmerer, Susanne; Chow, Wah Soon

    2014-11-01

    We sought a rapid, non-intrusive, whole-tissue measure of the functional photosystem II (PS II) content in leaves. Summation of electrons, delivered by a single-turnover flash to P700(+) (oxidized PS I primary donor) in continuous background far-red light, gave a parameter S in absorbance units after taking into account an experimentally determined basal electron flux that affects P700 redox kinetics. S was linearly correlated with the functional PS II content measured by the O(2) yield per single-turnover repetitive flash in Arabidopsis thaliana expressing an antisense construct to the PsbO (manganese-stabilizing protein in PS II) proteins of PS II (PsbO mutants). The ratio of S to z(max) (total PS I content in absorbance units) was comparable to the PS II/PS I reaction-center ratio in wild-type A. thaliana and in control Spinacea oleracea. Both S and S/z(max) decreased in photoinhibited spinach leaf discs. The whole-tissue functional PS II content and the PS II/photosystem I (PS I) ratio can be non-intrusively monitored by S and S/z(max), respectively, using a quick P700 absorbance protocol compatible with modern P700 instruments.

  12. Non-Intrusive, Laser-Based Imaging of Jet-A Fuel Injection and Combustion Species in High Pressure, Subsonic Flows

    NASA Technical Reports Server (NTRS)

    Locke, Randy J.; Hicks, Yolanda R.; Anderson, Robert C.; deGroot, Wilhelmus A.

    2001-01-01

    The emphasis of combustion research efforts at NASA Glenn Research Center (GRC) is on collaborating with industry to design and test gas-turbine combustors and subcomponents for both sub- and supersonic applications. These next-generation aircraft combustors are required to meet strict international environmental restrictions limiting emissions. To meet these goals, innovative combustor concepts require operation at temperatures and pressures far exceeding those of cur-rent designs. New and innovative diagnostic tools are necessary to characterize these flow streams since existing methods are inadequate. The combustion diagnostics team at GRC has implemented a suite of highly sensitive, nonintrusive optical imaging methods to diagnose the flowfields of these new engine concepts. By using optically accessible combustors and flametubes, imaging of fuel and intermediate combustion species via planar laser-induced fluorescence (PLIF) at realistic pressures are now possible. Direct imaging of the fuel injection process through both planar Mie scattering and PLIF methods is also performed. Additionally, a novel combination of planar fuel fluorescence imaging and computational analysis allows a 3-D examination of the flowfield, resulting in spatially and temporally resolved fuel/air volume distribution maps. These maps provide detailed insight into the fuel injection process at actual conditions, thereby greatly enhancing the evaluation of fuel injector performance and other combustion phenomena. Stable species such as CO2, O2, N2O. and hydrocarbons are also investigated by a newly demonstrated 1-D, spontaneous Raman spectroscopic method. This visible wavelength Raman technique allows the acquisition of quantitative. stable species concentration measurements from the flow.

  13. Non-Intrusive, Laser-Based Imaging of Jet-A Fuel Injection and Combustion Species in High Pressure, Subsonic Flows

    NASA Technical Reports Server (NTRS)

    Locke, R. J.; Hicks, Y. R.; Anderson, R. C.; deGroot, W. A.

    2000-01-01

    The emphasis of combustion research efforts at NASA Glenn Research Center (GRC) is on collaborating with industry to design and test gas-turbine combustors and subcomponents for both sub- and supersonic applications. These next-generation aircraft combustors are required to meet strict international environmental restrictions limiting emissions. To meet these goals, innovative combustor concepts require operation at temperatures and pressures far exceeding those of current designs. New and innovative diagnostic tools are necessary to characterize these flow streams since existing methods are inadequate. The combustion diagnostics team at GRC has implemented a suite of highly sensitive, nonintrusive optical imaging methods to diagnose the flowfields of these new engine concepts. By using optically accessible combustors and flame-tubes, imaging of fuel and intermediate combustion species via planar laser-induced fluorescence (PLIF) at realistic pressures are now possible. Direct imaging of the fuel injection process through both planar Mie scattering and PLIF methods is also performed. Additionally, a novel combination of planar fuel fluorescence imaging and computational analysis allows a 3-D examination of the flowfield, resulting in spatially and temporally resolved fuel/air volume distribution maps. These maps provide detailed insight into the fuel injection process at actual conditions, thereby greatly enhancing the evaluation of fuel injector performance and other combustion phenomena. Stable species such as CO2, O2, N2, H2O, and hydrocarbons are also investigated by a newly demonstrated 1-D, spontaneous Raman spectroscopic method. This visible wavelength Raman technique allows the acquisition of quantitative, stable species concentration measurements from the flow.

  14. General Characterization Methods for Photoelectrochemical Cells for Solar Water Splitting.

    PubMed

    Shi, Xinjian; Cai, Lili; Ma, Ming; Zheng, Xiaolin; Park, Jong Hyeok

    2015-10-12

    Photoelectrochemical (PEC) water splitting is a very promising technology that converts water into clean hydrogen fuel and oxygen by using solar light. However, the characterization methods for PEC cells are diverse and a systematic introduction to characterization methods for PEC cells has rarely been attempted. Unlike most other review articles that focus mainly on the material used for the working electrodes of PEC cells, this review introduces general characterization methods for PEC cells, including their basic configurations and methods for characterizing their performance under various conditions, regardless of the materials used. Detailed experimental operation procedures with theoretical information are provided for each characterization method. The PEC research area is rapidly expanding and more researchers are beginning to devote themselves to related work. Therefore, the content of this Minireview can provide entry-level knowledge to beginners in the area of PEC, which might accelerate progress in this area.

  15. Methods for Characterization of Alternative RNA Splicing.

    PubMed

    Harvey, Samuel E; Cheng, Chonghui

    2016-01-01

    Quantification of alternative splicing to detect the abundance of differentially spliced isoforms of a gene in total RNA can be accomplished via RT-PCR using both quantitative real-time and semi-quantitative PCR methods. These methods require careful PCR primer design to ensure specific detection of particular splice isoforms. We also describe analysis of alternative splicing using a splicing "minigene" in mammalian cell tissue culture to facilitate investigation of the regulation of alternative splicing of a particular exon of interest.

  16. Spectral methods applied to fluidized-bed combustors

    SciTech Connect

    Brown, R.C.; Raines, T.S.; Thiede, T.D.

    1995-11-01

    The goal of this research is to characterize coals and sorbents during the normal operation of an industrial-scale circulating fluidized bed (CFB) boiler. The method determines coal or sorbent properties based on the analysis of transient CO{sub 2} or SO{sub 2} emissions from the boiler. Fourier Transform Infrared (FTIR) spectroscopy is used to qualitatively and quantitatively analyze the gaseous products of combustion. Spectral analysis applied to the transient response of CO{sub 2} and SO{sub 2} resulting from introduction of a batch of coal or limestone into the boiler yields characteristic time constants from which combustion or sorbent models are developed. The method is non-intrusive and is performed under realistic combustion conditions. Results are presented from laboratory studies and power plant monitoring.

  17. A thermoluminescent method for aerosol characterization

    NASA Technical Reports Server (NTRS)

    Long, E. R., Jr.; Rogowski, R. S.

    1976-01-01

    A thermoluminescent method has been used to study the interactions of aerosols with ozone. The preliminary results show that ozone reacts with many compounds found in aerosols, and that the thermoluminescence curves obtained from ozonated aerosols are characteristic of the aerosol. The results suggest several important applications of the thermoluminescent method: development of a detector for identification of effluent sources; a sensitive experimental tool for study of heterogeneous chemistry; evaluation of importance of aerosols in atmospheric chemistry; and study of formation of toxic, electronically excited species in airborne particles.

  18. Methods of characterization of synthetic opal films

    NASA Astrophysics Data System (ADS)

    Koryukin, A. V.; Akhmadeev, A. A.; Salakhov, M. Kh

    2013-12-01

    We developed methods for determination of thickness, number of layers and filling fraction of silica particles for synthetic opals. We show that the filling fraction is considerably less than for ideal close-packed structure, which is important for practical and theoretical applications.

  19. Method For Characterizing Residual Stress In Metals

    DOEpatents

    Jacobson, Loren A.; Michel, David J.; Wyatt, Jeffrey R.

    2002-12-03

    A method is provided for measuring the residual stress in metals. The method includes the steps of drilling one or more holes in a metal workpiece to a preselected depth and mounting one or more acoustic sensors on the metal workpiece and connecting the sensors to an electronic detecting and recording device. A liquid metal capable of penetrating into the metal workpiece placed at the bottom of the hole or holes. A recording is made over a period of time (typically within about two hours) of the magnitude and number of noise events which occur as the liquid metal penetrates into the metal workpiece. The magnitude and number of noise events are then correlated to the internal stress in the region of the workpiece at the bottom of the hole.

  20. a Novel Method for Gas Sensors Characterization

    NASA Astrophysics Data System (ADS)

    Mielle, P.; Marquis, F.; Trivier, V.

    2000-12-01

    For E-nose applications, sensors are never specified towards the aroma chemicals, because it is difficult to generate a known amount of chemical vapours from a condensed phase. A method was developed, that allows the specification of gas sensors towards food samples, using a GC/sensors coupling. We have found the ADL lower than the GC-FID detector, and an unexpected response for E.V. Olive Oil.

  1. Analysis of Uncertainty and Variability in Finite Element Computational Models for Biomedical Engineering: Characterization and Propagation

    PubMed Central

    Mangado, Nerea; Piella, Gemma; Noailly, Jérôme; Pons-Prats, Jordi; Ballester, Miguel Ángel González

    2016-01-01

    Computational modeling has become a powerful tool in biomedical engineering thanks to its potential to simulate coupled systems. However, real parameters are usually not accurately known, and variability is inherent in living organisms. To cope with this, probabilistic tools, statistical analysis and stochastic approaches have been used. This article aims to review the analysis of uncertainty and variability in the context of finite element modeling in biomedical engineering. Characterization techniques and propagation methods are presented, as well as examples of their applications in biomedical finite element simulations. Uncertainty propagation methods, both non-intrusive and intrusive, are described. Finally, pros and cons of the different approaches and their use in the scientific community are presented. This leads us to identify future directions for research and methodological development of uncertainty modeling in biomedical engineering. PMID:27872840

  2. Analysis of Uncertainty and Variability in Finite Element Computational Models for Biomedical Engineering: Characterization and Propagation.

    PubMed

    Mangado, Nerea; Piella, Gemma; Noailly, Jérôme; Pons-Prats, Jordi; Ballester, Miguel Ángel González

    2016-01-01

    Computational modeling has become a powerful tool in biomedical engineering thanks to its potential to simulate coupled systems. However, real parameters are usually not accurately known, and variability is inherent in living organisms. To cope with this, probabilistic tools, statistical analysis and stochastic approaches have been used. This article aims to review the analysis of uncertainty and variability in the context of finite element modeling in biomedical engineering. Characterization techniques and propagation methods are presented, as well as examples of their applications in biomedical finite element simulations. Uncertainty propagation methods, both non-intrusive and intrusive, are described. Finally, pros and cons of the different approaches and their use in the scientific community are presented. This leads us to identify future directions for research and methodological development of uncertainty modeling in biomedical engineering.

  3. Standard method for characterizing SERS substrates

    NASA Astrophysics Data System (ADS)

    Guicheteau, Jason A.; Hankus, Mikella E.; Christesen, Steven D.; Fountain, Augustus W., III; Pellegrino, Paul M.; Emmons, Erik D.; Tripathi, Ashish; Wilcox, Phillip; Emge, Darren

    2012-06-01

    We present the methodology and results of a standard assessment protocol to evaluate disparate SERS substrates that were developed for the Defense Advanced Research Programs Agency (DARPA) SERS Science and Technology Fundamentals Program. The results presented are a snapshot of a collaborative effort between the US Army Edgewood Chemical Biological Center, and the US Army Research Laboratory-Aldelphi Laboratory Center to develop a quantitative analytical method with spectroscopic figures of merit to unambiguously compare the sensitivity and reproducibility of various SERS substrates submitted by the program participants. We present the design of a common assessment protocol and the definition of a SERS enhancement value (SEV) in order to effectively compare SERS active surfaces.

  4. Novel method to characterize superhydrophobic coatings.

    PubMed

    Samaha, Mohamed A; Vahedi Tafreshi, Hooman; Gad-el-Hak, Mohamed

    2013-04-01

    Superhydrophobic coatings possess a strong water-repellent characteristic, which, among several other potential applications, enhances the mobility of water droplets over the surface. The coating traps air within its micropores, such that a submerged moving body experiences shear-free and no-slip regions over, respectively, the air pockets and the solid surface. This, in turn, may lead to significant skin-friction reduction. The coating maintains its superhydrophobicity as long as the air remains entrapped. It is therefore of great interest to precisely measure the amount of trapped air, which is particularly difficult to estimate for coatings with disordered microstructures. A novel method to measure the effective thickness and gas volume fraction of superhydrophobic coatings with either ordered or random microroughness is advanced. The technique is applied to both aerogel and electrospun fibrous coatings. The experiments utilize a sensitive weighing scale (down to 10(-4) gm) and height gauge (down to 10 μm) to determine the buoyancy force on an immersed, coated glass-slide substrate. The measured force is used to calculate the volume fraction of entrapped air. The coating's effective thickness also follows from the same calculations. The sensitivity of our particular scale enables the measuring of thicknesses down to 3 μm, which is not readily possible with conventional thickness gauges. Smaller thicknesses could be measured using more sensitive scales.

  5. ASTM test methods for composite characterization and evaluation

    NASA Technical Reports Server (NTRS)

    Masters, John E.

    1994-01-01

    A discussion of the American Society for Testing and Materials is given. Under the topic of composite materials characterization and evaluation, general industry practice and test methods for textile composites are presented.

  6. Exactly Embedded Wavefunction Methods for Characterizing Nitrogen Reduction Catalysis

    DTIC Science & Technology

    2015-01-15

    AFRL-OSR-VA-TR-2015-0038 Exactly Embedded Wavefunction Methods for Characterizing Nitrogen THOMAS MILLER CALIFORNIA INSTITUTE OF TECHNOLOGY Final...SUBTITLE Exactly Embedded Wavefunction Methods for Characterizing Nitrogen Reduction Catalysis 5a. CONTRACT NUMBER N/A 5b. GRANT NUMBER FA9550...catalysis, such as hydrogen and nitrogen reduction. In a significant methodological advance from the past year, we developed an accurate and

  7. Site characterization and petroleum hydrocarbon plume mapping

    SciTech Connect

    Ravishankar, K.

    1996-12-31

    This paper presents a case study of site characterization and hydrocarbon contamination plume mapping/delineation in a gas processing plant in southern Mexico. The paper describes innovative and cost-effective use of passive (non-intrusive) and active (intrusive) techniques, including the use of compound-specific analytical methods for site characterization. The techniques used, on a demonstrative basis, include geophysical, geochemical, and borehole drilling. Geochemical techniques used to delineate the horizontal extent of hydrocarbon contamination at the site include soil gas surveys. The borehole drilling technique used to assess the vertical extent of contamination and confirm geophysical and geochemical data combines conventional hollow-stem auguring with direct push-probe using Geoprobe. Compound-specific analytical methods, such as hydrocarbon fingerprinting and a modified method for gasoline range organics, demonstrate the inherent merit and need for such analyses to properly characterize a site, while revealing the limitations of noncompound-specific total petroleum hydrocarbon analysis. The results indicate that the techniques used in tandem can properly delineate the nature and extent of contamination at a site; often supplement or complement data, while reducing the risk of errors and omissions during the assessment phase; and provide data constructively to focus site-specific remediation efforts. 7 figs.

  8. Method for material characterization in a non-anechoic environment

    NASA Astrophysics Data System (ADS)

    Pometcu, L.; Sharaiha, A.; Benzerga, R.; Tamas, R. D.; Pouliguen, P.

    2016-04-01

    This paper presents a characterization method for extracting the reflection coefficient of materials and the real part of their permittivity. The characterization is performed in a real environment, as opposed to the classical measurement methods that require an anechoic chamber. In order to reduce the effects of the multipath propagation, a free space bistatic measurement was performed at different distances material-antennas in far field. By using a Teflon sample and a commercial absorbing material sample, measurements have been performed in order to validate the characterization technique.

  9. The characterization of kerogen-analytical limitations and method design

    SciTech Connect

    Larter, S.R.

    1987-04-01

    Methods suitable for high resolution total molecular characterization of kerogens and other polymeric SOM are necessary for a quantitative understanding of hydrocarbon maturation and migration phenomena in addition to being a requirement for a systematic understanding of kerogen based fuel utilization. Gas chromatographic methods, in conjunction with analytical pyrolysis methods, have proven successful in the rapid superficial characterization of kerogen pyrolysates. Most applications involve qualitative or semi-quantitative assessment of the relative concentration of aliphatic, aromatic, or oxygen-containing species in a kerogen pyrolysate. More recently, the use of alkylated polystyrene internal standards has allowed the direct determination of parameters related to the abundance of, for example, normal alkyl groups or single ring aromatic species in kerogens. The future of methods of this type for improved kerogen typing is critically discussed. The conceptual design and feasibility of methods suitable for the more complete characterization of complex geopolymers on the molecular level is discussed with practical examples.

  10. Transuranic waste characterization sampling and analysis methods manual. Revision 1

    SciTech Connect

    Suermann, J.F.

    1996-04-01

    This Methods Manual provides a unified source of information on the sampling and analytical techniques that enable Department of Energy (DOE) facilities to comply with the requirements established in the current revision of the Transuranic Waste Characterization Quality Assurance Program Plan (QAPP) for the Waste Isolation Pilot Plant (WIPP) Transuranic (TRU) Waste Characterization Program (the Program) and the WIPP Waste Analysis Plan. This Methods Manual includes all of the testing, sampling, and analytical methodologies accepted by DOE for use in implementing the Program requirements specified in the QAPP and the WIPP Waste Analysis Plan. The procedures in this Methods Manual are comprehensive and detailed and are designed to provide the necessary guidance for the preparation of site-specific procedures. With some analytical methods, such as Gas Chromatography/Mass Spectrometry, the Methods Manual procedures may be used directly. With other methods, such as nondestructive characterization, the Methods Manual provides guidance rather than a step-by-step procedure. Sites must meet all of the specified quality control requirements of the applicable procedure. Each DOE site must document the details of the procedures it will use and demonstrate the efficacy of such procedures to the Manager, National TRU Program Waste Characterization, during Waste Characterization and Certification audits.

  11. New Laboratory Methods for Characterizing the Immersion Factors for Irradiance

    NASA Technical Reports Server (NTRS)

    Hooker, Stanford B. (Editor); Firestone, Elaine R. (Editor); Zibordi, Giuseppe; DAlimonte, Davide; vaderLinde, Dirk; Brown, James W.

    2003-01-01

    The experimental determination of the immersion factor, I(sub f)(lambda), of irradiance collectors is a requirement of any in-water radiometer. The eighth SeaWiFS Intercalibration Round-Robin Experiment (SIRREX-8) showed different implementations, at different laboratories, of the same I(sub f)(lambda) measurement protocol. The different implementations make use of different setups, volumes, and water types. Consequently, they exhibit different accuracies and require different execution times for characterizing an irradiance sensor. In view of standardizing the characterization of I(sub f)(lambda) values for in-water radiometers, together with an increase in the accuracy of methods and a decrease in the execution time, alternative methods are presented, and assessed versus the traditional method. The proposed new laboratory methods include: a) the continuous method, in which optical measurements taken with discrete water depths are substituted by continuous profiles created by removing the water from the water vessel at a constant flow rate (which significantly reduces the time required for the characterization of a single radiometer); and b) the Compact Portable Advanced Characterization Tank (ComPACT) method, in which the commonly used large tanks are replaced by a small water vessel, thereby allowing the determination of I(sub f)(lambda) values with a small water volume, and more importantly, permitting I(sub f)(lambda) characterizations with pure water. Intercomparisons between the continuous and the traditional method showed results within the variance of I(sub f) (lambda) determinations. The use of the continuous method, however, showed a much shorter realization time. Intercomparisons between the ComPACT and the traditional method showed generally higher I(sub f)(lambda) values for the former. This is in agreement with the generalized expectations of a reduction in scattering effects, because of the use of pure water with the ComPACT method versus the use of

  12. Methodology Using Inverse Methods for Pit Characterization in Multilayer Structures

    NASA Astrophysics Data System (ADS)

    Aldrin, John C.; Sabbagh, Harold A.; Sabbagh, Elias H.; Murphy, R. Kim; Concordia, Michael; Judd, David R.; Lindgren, Eric; Knopp, Jeremy

    2006-03-01

    This paper presents a methodology incorporating ultrasonic and eddy current data and NDE models to characterize pits in first and second layers. Approaches such as equivalent pit dimensions, approximate probe models, and iterative inversion schemes were designed to improve the reliability and speed of inverse methods for second layer pit characterization. A novel clutter removal algorithm was developed to compensate for coherent background noise. Validation was achieved using artificial and real pitting corrosion samples.

  13. Methods of Isolation and Characterization of Oligogalacturonide Elicitors.

    PubMed

    Benedetti, Manuel; Mattei, Benedetta; Pontiggia, Daniela; Salvi, Gianni; Savatin, Daniel Valentin; Ferrari, Simone

    2017-01-01

    Oligogalacturonides (OGs) are pectic fragments derived from the partial degradation of homogalacturonan in the plant cell wall and able to elicit plant defence responses. Recent methodological advances in the isolation of OGs from plant tissues and their characterization have confirmed their role as bona fide plant Damage-Associated Molecular Patterns. Here, we describe the methods for the isolation of OGs from Arabidopsis leaf tissues and for the characterization of OG structure and biological activity.

  14. Non-intrusive measurement of particle charge: Electrostatic dry coal cleaning. Technical progress report No. 11, January 1, 1994--March 31, 1994

    SciTech Connect

    Not Available

    1994-06-01

    As has been previously reported, the charge measurement portion of this project has been broadened to include direct measurement techniques which yield an average particle charge per unit mass. These methods, which now include current measurements from the charging loop, an electrolytic collection solution and a Faraday cage have been employed to expand the charge measurement capabilities over those that were originally developed using the PDPA. The effects of gas velocity, humidity and temperature as well as particle size on charge was evaluated for different coals and silica. The charge accumulated on silica particles was linearly dependent on their velocity in the tribocharger for the velocities and mass loadings which were investigated. For coals, a linear increase in charge occurred over a more limited velocity range. Transport gas humidity had a much stronger effect on the charge established on silica particles than on coal particles.

  15. Quantification and correction of the error due to limited PIV resolution on the accuracy of non-intrusive spatial pressure measurement using a DNS channel flow database

    NASA Astrophysics Data System (ADS)

    Liu, Xiaofeng; Siddle-Mitchell, Seth

    2016-11-01

    The effect of the subgrid-scale (SGS) stress due to limited PIV resolution on pressure measurement accuracy is quantified using data from a direct numerical simulation database of turbulent channel flow (JHTDB). A series of 2000 consecutive realizations of sample block data with 512x512x49 grid nodal points were selected and spatially filtered with a coarse 17x17x17 and a fine 5x5x5 box averaging, respectively, giving rise to corresponding PIV resolutions of roughly 62.6 and 18.4 times of the viscous length scale. Comparison of the reconstructed pressure at different levels of pressure gradient approximation with the filtered pressure shows that the neglect of the viscous term leads to a small but noticeable change in the reconstructed pressure, especially in regions near the channel walls. As a contrast, the neglect of the SGS stress results in a more significant increase in both the bias and the random errors, indicating the SGS term must be accounted for in PIV pressure measurement. Correction using similarity SGS modeling reduces the random error due to the omission of SGS stress from 114.5% of the filtered pressure r.m.s. fluctuation to 89.1% for the coarse PIV resolution, and from 66.5% to 35.9% for the fine PIV resolution, respectively, confirming the benefit of the error compensation method and the positive influence of increasing PIV resolution on pressure measurement accuracy improvement.

  16. Soil characterization methods for unsaturated low-level waste sites

    SciTech Connect

    Wierenga, P.J.; Young, M.H. . Dept. of Soil and Water Science); Gee, G.W.; Kincaid, C.T. ); Hills, R.G. . Dept. of Mechanical Engineering); Nicholson, T.J.; Cady, R.E. )

    1993-01-01

    To support a license application for the disposal of low-level radioactive waste (LLW), applicants must characterize the unsaturated zone and demonstrate that waste will not migrate from the facility boundary. This document provides a strategy for developing this characterization plan. It describes principles of contaminant flow and transport, site characterization and monitoring strategies, and data management. It also discusses methods and practices that are currently used to monitor properties and conditions in the soil profile, how these properties influence water and waste migration, and why they are important to the license application. The methods part of the document is divided into sections on laboratory and field-based properties, then further subdivided into the description of methods for determining 18 physical, flow, and transport properties. Because of the availability of detailed procedures in many texts and journal articles, the reader is often directed for details to the available literature. References are made to experiments performed at the Las Cruces Trench site, New Mexico, that support LLW site characterization activities. A major contribution from the Las Cruces study is the experience gained in handling data sets for site characterization and the subsequent use of these data sets in modeling studies.

  17. Porosity and Variations in Microgravity Aerogel Nano-Structures. 2; New Laser Speckle Characterization Methods

    NASA Technical Reports Server (NTRS)

    Hunt, A. J.; Ayers, M. R.; Sibille, L.; Smith, D. D.

    2001-01-01

    The transition from sol to gel is a process that is critical to the properties of engineered nanomaterials, but one with few available techniques for observing the dynamic processes occurring during the evolution of the gel network. Specifically, the observation of various cluster aggregation models, such as diffusion-limited and reaction-limited cluster growth can be quite difficult. This can be rather important as the actual aggregation model can dramatically influence the mechanical properties of gels, and is significantly affected by the presence of convective flows, or their absence in microgravity. We have developed two new non-intrusive optical methods for observing the aggregation processes within gels in real time. These make use of the dynamic behavior of laser speckle patterns produced when an intense laser source is passed through a gelling sol. The first method is a simplified time-correlation measurement, where the speckle pattern is observed using a CCD camera and information on the movement of the scattering objects is readily apparent. This approach is extremely sensitive to minute variations in the flow field as the observed speckle pattern is a diffraction-based image, and is therefore sensitive to motions within the sol on the order of the wavelength of the probing light. Additionally, this method has proven useful in determining a precise time for the gel-point, an event often difficult to measure. Monitoring the evolution of contrast within the speckle field is another method that has proven useful for studying aeration. In this case, speckle contrast is dependent upon the size (correlation length) and number of scattering centers, increasing with increasing size, and decreasing with increasing numbers. The dynamic behavior of cluster growth in gels causes both of these to change simultaneously with time, the exact rate of which is determined by the specific aggregation model involved. Actual growth processes can now be observed, and the

  18. Technical Advice and Support for the Joint Integrated Non-Intrusive Inspection (JINII) Program Task 2.2 Transmission Digital Radiography (DR)

    SciTech Connect

    Martz, H; Chinn, D; Pincus, C

    2011-03-03

    The Cargo Advanced Automated Radiography System (CAARS) program aims to utilize advanced radiographic systems to detect radiological and nuclear threats. Validation of initial design and testing concepts is a precondition for prototype system development and large-scale deployment. As expected, Depleted Uranium (DU) is a valid surrogate for Special Nuclear Materials (SNM) in CAARS Advanced Technology Demonstration (ATD) performance field-tests of transmission radiography systems. Dual-energy transmission measurements of DU are nearly identical to SNM, and are distinct from lower Z materials, provided the samples are matched to equal areal density. Results from an alternative method, using samples of equal thickness, showed sample discrimination by material density, rather than by atomic number (Z). The transmission measurements of DU and SNM were made with equipment that is nearly identical to current field systems. X-ray source beams at endpoint energies of 5.4 MeV and 9.6 MeV were used to measure transmission through the selected sample materials. The ratio of the x-ray linear attenuation coefficient times length ({micro}L) at 5.4 MeV, to {micro}L at 9.6 MeV is a metric for atomic number based discrimination of materials. The measured ratios were compared with computed values based on LLNL photon cross section data and LLNL developed models of x-ray detector characteristics. Measured ratios for DU differed from HEU by an average of 0.25%, and from WGPu by 0.08%, which is within the noise level of 0.4 to 0.5%. For comparison, measured ratios for Sn differed from HEU by 3.2%, and from WGPu by 3.6%, well beyond the measurement noise. Measured ratios for W differed from HEU by 0.01%, and from WGPu by 0.32%. The measured ratio values presented in Table 1 demonstrate the feasibility of using a threshold ratio to discriminate low-Z (Z < 72) from high-Z (Z {ge} 72) materials (as defined by CAARS specification). In the case of our test system, a threshold ratio of 1

  19. Bayesian methods for characterizing unknown parameters of material models

    DOE PAGES

    Emery, J. M.; Grigoriu, M. D.; Field Jr., R. V.

    2016-02-04

    A Bayesian framework is developed for characterizing the unknown parameters of probabilistic models for material properties. In this framework, the unknown parameters are viewed as random and described by their posterior distributions obtained from prior information and measurements of quantities of interest that are observable and depend on the unknown parameters. The proposed Bayesian method is applied to characterize an unknown spatial correlation of the conductivity field in the definition of a stochastic transport equation and to solve this equation by Monte Carlo simulation and stochastic reduced order models (SROMs). As a result, the Bayesian method is also employed tomore » characterize unknown parameters of material properties for laser welds from measurements of peak forces sustained by these welds.« less

  20. Bayesian methods for characterizing unknown parameters of material models

    SciTech Connect

    Emery, J. M.; Grigoriu, M. D.; Field Jr., R. V.

    2016-02-04

    A Bayesian framework is developed for characterizing the unknown parameters of probabilistic models for material properties. In this framework, the unknown parameters are viewed as random and described by their posterior distributions obtained from prior information and measurements of quantities of interest that are observable and depend on the unknown parameters. The proposed Bayesian method is applied to characterize an unknown spatial correlation of the conductivity field in the definition of a stochastic transport equation and to solve this equation by Monte Carlo simulation and stochastic reduced order models (SROMs). As a result, the Bayesian method is also employed to characterize unknown parameters of material properties for laser welds from measurements of peak forces sustained by these welds.

  1. A Method for Characterizing the Surface Cleanliness During Adhesion Testing

    DTIC Science & Technology

    1969-03-01

    It has been shown that the degree of adhesion of metals depends upon the surface cleanliness . This paper presents a method that was used to...characterize the surface cleanliness of nickel during an adhesion experiment. The change in the work function of the surface as the metal was cleaned was used

  2. Overview of geotechnical methods to characterize rock masses

    SciTech Connect

    Heuze, F.E.

    1981-12-01

    The methods that are used to characterize discontinuous rock masses from a geotechnical point of view are summarized. Emphasis is put on providing key references on each subject. The topics of exploration, in-situ stresses, mechanical properties, thermal properties, and hydraulic properties are addressed.

  3. Methods And Devices For Characterizing Duplex Nucleic Acid Molecules

    DOEpatents

    Akeson, Mark; Vercoutere, Wenonah; Haussler, David; Winters-Hilt, Stephen

    2005-08-30

    Methods and devices are provided for characterizing a duplex nucleic acid, e.g., a duplex DNA molecule. In the subject methods, a fluid conducting medium that includes a duplex nucleic acid molecule is contacted with a nanopore under the influence of an applied electric field and the resulting changes in current through the nanopore caused by the duplex nucleic acid molecule are monitored. The observed changes in current through the nanopore are then employed as a set of data values to characterize the duplex nucleic acid, where the set of data values may be employed in raw form or manipulated, e.g., into a current blockade profile. Also provided are nanopore devices for practicing the subject methods, where the subject nanopore devices are characterized by the presence of an algorithm which directs a processing means to employ monitored changes in current through a nanopore to characterize a duplex nucleic acid molecule responsible for the current changes. The subject methods and devices find use in a variety of applications, including, among other applications, the identification of an analyte duplex DNA molecule in a sample, the specific base sequence at a single nulceotide polymorphism (SNP), and the sequencing of duplex DNA molecules.

  4. DNAPL characterization using the Ribbon NAPL sampler: Methods and results

    SciTech Connect

    Riha, B.D.

    2000-04-25

    The Ribbon NAPL Sampler (RNS) is a direct sampling device that provides detailed depth discrete mapping of Non Aqueous Phase Liquids (NAPLs) in a borehole. This characterization method provides a yes or no answer to the presence of NAPLs and is used to complement and enhance other characterization techniques. Several cone penetrometer deployment methods are in use and methods for other drilling techniques are under development. The RNS has been deployed in the vadose and saturated zones at four different sites. Three of the sites contain DNAPLs from cleaning and degreasing operations and the fourth site contains creosote from a wood preserving plant. A brief description of the process history and geology is provided for each site. Where available, lithology and contaminant concentration information is provided and discussed in context with the RNS results.

  5. Methods to characterize non-Gaussian noise in TAMA

    NASA Astrophysics Data System (ADS)

    Ando, Masaki; Arai, K.; Takahashi, R.; Tatsumi, D.; Beyersdorf, P.; Kawamura, S.; Miyoki, S.; Mio, N.; Moriwaki, S.; Numata, K.; Kanda, N.; Aso, Y.; Fujimoto, M.-K.; Tsubono, K.; Kuroda, K.; TAMA Collaboration

    2003-09-01

    We present a data characterization method for the main output signal of the interferometric gravitational-wave detector, in particular targetting at effective detection of burst gravitational waves from stellar core collapse. The time scale of non-Gaussian events is evaluated in this method, and events with longer time scale than real signals are rejected as non-Gaussian noises. As a result of data analysis using 1000 h of real data with the interferometric gravitational-wave detector TAMA300, the false-alarm rate was improved 103 times with this non-Gaussian noise evaluation and rejection method.

  6. The numerical mirage method for photothermal characterization of materials.

    PubMed

    Demko, Michael T; Hostler, Stephen R; Abramson, Alexis R

    2008-04-01

    Noncontact thermal measurement techniques offer rapid thermal characterization without modification or destruction of the sample being studied. A simple and versatile method has been developed, termed the "numerical mirage method," that utilizes the transient photothermal deflection of a laser beam traversing a modulated temperature gradient. This method expands the range and simplifies the experimental procedure of traditional mirage methods. A numerical solver is used to create accurate deflection profile models and a linear curve fitting routine is developed, from which the thermal diffusivity of a material may be determined. This method allows for rapid modification of sample and heating configurations. Verification of the method is performed on bismuth and fused quartz reference samples, and good agreement with literature is obtained.

  7. Integrating asthma hazard characterization methods for consumer products.

    PubMed

    Maier, A; Vincent, M J; Gadagbui, B; Patterson, J; Beckett, W; Dalton, P; Kimber, I; Selgrade, M J K

    2014-10-01

    Despite extensive study, definitive conclusions regarding the relationship between asthma and consumer products remain elusive. Uncertainties reflect the multi-faceted nature of asthma (i.e., contributions of immunologic and non-immunologic mechanisms). Many substances used in consumer products are associated with occupational asthma or asthma-like syndromes. However, risk assessment methods do not adequately predict the potential for consumer product exposures to trigger asthma and related syndromes under lower-level end-user conditions. A decision tree system is required to characterize asthma and respiratory-related hazards associated with consumer products. A system can be built to incorporate the best features of existing guidance, frameworks, and models using a weight-of-evidence (WoE) approach. With this goal in mind, we have evaluated chemical hazard characterization methods for asthma and asthma-like responses. Despite the wealth of information available, current hazard characterization methods do not definitively identify whether a particular ingredient will cause or exacerbate asthma, asthma-like responses, or sensitization of the respiratory tract at lower levels associated with consumer product use. Effective use of hierarchical lines of evidence relies on consideration of the relevance and potency of assays, organization of assays by mode of action, and better assay validation. It is anticipated that the analysis of existing methods will support the development of a refined WoE approach.

  8. Integral structural-functional method for characterizing microbial populations

    NASA Astrophysics Data System (ADS)

    Yakushev, A. V.

    2015-04-01

    An original integral structural-functional method has been proposed for characterizing microbial communities. The novelty of the approach is the in situ study of microorganisms based on the growth kinetics of microbial associations in liquid nutrient broth media under selective conditions rather than on the level of taxa or large functional groups. The method involves the analysis of the integral growth model of a periodic culture. The kinetic parameters of such associations reflect their capacity of growing on different media, i.e., their physiological diversity, and the metabolic capacity of the microorganisms for growth on a nutrient medium. Therefore, the obtained parameters are determined by the features of the microbial ecological strategies. The inoculation of a dense medium from the original inoculate allows characterizing the taxonomic composition of the dominants in the soil community. The inoculation from the associations developed on selective media characterizes the composition of syntrophic groups, which fulfill a specific function in nature. This method is of greater information value than the classical methods of inoculation on selective media.

  9. Tracer Methods for Characterizing Fracture Creation in Engineered Geothermal Systems

    SciTech Connect

    Rose, Peter; Harris, Joel

    2014-05-08

    The aim of this proposal is to develop, through novel high-temperature-tracing approaches, three technologies for characterizing fracture creation within Engineered Geothermal Systems (EGS). The objective of a first task is to identify, develop and demonstrate adsorbing tracers for characterizing interwell reservoir-rock surface areas and fracture spacing. The objective of a second task is to develop and demonstrate a methodology for measuring fracture surface areas adjacent to single wells. The objective of a third task is to design, fabricate and test an instrument that makes use of tracers for measuring fluid flow between newly created fractures and wellbores. In one method of deployment, it will be used to identify qualitatively which fractures were activated during a hydraulic stimulation experiment. In a second method of deployment, it will serve to measure quantitatively the rate of fluid flowing from one or more activated fracture during a production test following a hydraulic stimulation.

  10. Analytical Methods for Biomass Characterization during Pretreatment and Bioconversion

    SciTech Connect

    Pu, Yunqiao; Meng, Xianzhi; Yoo, Chang Geun; Li, Mi; Ragauskas, Arthur J

    2016-01-01

    Lignocellulosic biomass has been introduced as a promising resource for alternative fuels and chemicals because of its abundance and complement for petroleum resources. Biomass is a complex biopolymer and its compositional and structural characteristics largely vary depending on its species as well as growth environments. Because of complexity and variety of biomass, understanding its physicochemical characteristics is a key for effective biomass utilization. Characterization of biomass does not only provide critical information of biomass during pretreatment and bioconversion, but also give valuable insights on how to utilize the biomass. For better understanding biomass characteristics, good grasp and proper selection of analytical methods are necessary. This chapter introduces existing analytical approaches that are widely employed for biomass characterization during biomass pretreatment and conversion process. Diverse analytical methods using Fourier transform infrared (FTIR) spectroscopy, gel permeation chromatography (GPC), and nuclear magnetic resonance (NMR) spectroscopy for biomass characterization are reviewed. In addition, biomass accessibility methods by analyzing surface properties of biomass are also summarized in this chapter.

  11. A method for characterizing aerodynamic sound sources in turbomachines

    NASA Astrophysics Data System (ADS)

    Mongeau, L.; Thompson, D. E.; Mclaughlin, D. K.

    1995-03-01

    A method based on Weidemann's acoustic similarity laws [1] was used to investigate the aerodynamic sound generated by a partially ducted centrifugal pump rotor. The primary objective of the method was to determine the spectral characteristics of the sound source by isolating the effects of acoustic phenomena such as duct resonances or sound reflections. Pump-radiated sound pressure spectra were measured for different impeller rotational speeds, keeping the operating condition constant. The spectra, assumed to be expressed as the product of a source spectral distribution function and an acoustic frequency response function, were then decomposed into a product form following a computer-implemented algorithm. The method was successful in accurately determining the spectral distribution of the broadband aerodynamic noise generating mechanisms involved and that of the acoustic frequency response of the system. The absolute levels of the source function and the acoustic function were established by assuming that, over a limited low frequency range, the average gain of the frequency response function is unity so that comparisons between different pump operating conditions could be made. The source spectral distribution was found to be independent of the microphone location and the acoustic loading. When applicable, this method therefore allows the characterization of aerodynamic sound sources by measuring ordinary sound pressure spectra, at any one point around the source, without having to isolate the source from the system. The source characterization method was instrumental in the study of sound generation by rotating stall presented in a previous publication [2].

  12. DIII-D dust particulate characterization (June 1998 Vent)

    SciTech Connect

    Carmack, W.J.

    1999-01-01

    Dust is a key component of fusion power device accident source term. Understanding the amount of dust expected in fusion power devices and its physical and chemical characteristics is needed to verify assumptions currently used in safety analyses. An important part of this safety research and development work is to characterize dust from existing experimental tokamaks. In this report, the authors present the collection, data analysis methods used, and the characterization of dust particulate collected from various locations inside the General Atomics DIII-D vacuum vessel following the June 1998 vent. The collected particulate was analyzed at the Idaho National Engineering and Environmental Laboratory (INEEL). Two methods were used to collect particulate with the goal of preserving the particle size distribution and physical characteristics of the particulate. Choice of collection technique is important because the sampling method used can bias the particle size distribution collected. Vacuum collection on substrates and adhesion removal with metallurgical replicating tape were chosen as non-intrusive sampling methods. Seventeen samples were collected including plasma facing surfaces in lower, upper, and horizontal locations, surfaces behind floor tiles, surfaces behind divert or tiles, and surfaces behind ceiling tiles. The results of the analysis are presented.

  13. DIII-D Dust Particulate Characterization (June 1998 Vent)

    SciTech Connect

    Carmack, William Jonathan

    1999-01-01

    Dust is a key component of fusion power device accident source term. Understanding the amount of dust expected in fusion power devices and its physical and chemical characteristics is needed to verify assumptions currently used in safety analyses. An important part of this safety research and development work is to characterize dust from existing experimental tokamaks. In this report, we present the collection, data analysis methods used, and the characterization of dust particulate collected from various locations inside the General Atomics DIII-D vacuum vessel following the June 1998 vent. The collected particulate was analyzed at the Idaho National Engineering and Environmental Laboratory (INEEL). Two methods were used to collect particulate with the goal of preserving the particle size distribution and physical characteristics of the particulate. Choice of collection technique is important because the sampling method used can bias the particle size distribution collected. Vacuum collection on substrates and adhesion removal with metallurgical replicating tape were chosen as non-intrusive sampling methods. Seventeen samples were collected including plasma facing surfaces in lower, upper, and horizontal locations, surfaces behind floor tiles, surfaces behind divertor tiles, and surfaces behind ceiling tiles. The results of the analysis are presented.

  14. Characterizing lentic freshwater fish assemblages using multiple sampling methods

    USGS Publications Warehouse

    Fischer, Jesse R.; Quist, Michael

    2014-01-01

    Characterizing fish assemblages in lentic ecosystems is difficult, and multiple sampling methods are almost always necessary to gain reliable estimates of indices such as species richness. However, most research focused on lentic fish sampling methodology has targeted recreationally important species, and little to no information is available regarding the influence of multiple methods and timing (i.e., temporal variation) on characterizing entire fish assemblages. Therefore, six lakes and impoundments (48–1,557 ha surface area) were sampled seasonally with seven gear types to evaluate the combined influence of sampling methods and timing on the number of species and individuals sampled. Probabilities of detection for species indicated strong selectivities and seasonal trends that provide guidance on optimal seasons to use gears when targeting multiple species. The evaluation of species richness and number of individuals sampled using multiple gear combinations demonstrated that appreciable benefits over relatively few gears (e.g., to four) used in optimal seasons were not present. Specifically, over 90 % of the species encountered with all gear types and season combinations (N = 19) from six lakes and reservoirs were sampled with nighttime boat electrofishing in the fall and benthic trawling, modified-fyke, and mini-fyke netting during the summer. Our results indicated that the characterization of lentic fish assemblages was highly influenced by the selection of sampling gears and seasons, but did not appear to be influenced by waterbody type (i.e., natural lake, impoundment). The standardization of data collected with multiple methods and seasons to account for bias is imperative to monitoring of lentic ecosystems and will provide researchers with increased reliability in their interpretations and decisions made using information on lentic fish assemblages.

  15. A Novel Method for Characterizing Spacesuit Mobility Through Metabolic Cost

    NASA Technical Reports Server (NTRS)

    McFarland, Shane M.; Norcross, Jason R.

    2014-01-01

    Historically, spacesuit mobility has been characterized by directly measuring both range of motion and joint torque of individual anatomic joints. The work detailed herein aims to improve on this method, which is often prone to uncertainly, lack of repeatability, and a general lack of applicability to real-world functional tasks. Specifically, the goal of this work is to characterize suited mobility performance by directly measuring the metabolic performance of the occupant. Pilot testing was conducted in 2013, employing three subjects performing a range of functional tasks in two different suits prototypes, the Mark III and Z-1. Cursory analysis of the results shows the approach has merit, with consistent performance trends toward one suit over the other. Forward work includes the need to look at more subjects, a refined task set, and another suit in a different mass/mobility regime to validate the approach.

  16. Characterization of Engineered L1 Retrotransposition Events: The Recovery Method.

    PubMed

    Cano, David; Morell, Santiago; Pulgarin, Andres J; Amador, Suyapa; Garcia-Pérez, Jose L

    2016-01-01

    Long Interspersed Element class 1 retrotransposons (LINE-1 or L1) are abundant Transposable Elements in mammalian genomes and their mobility continues to impact the human genome. The development of engineered retrotransposition assays has been instrumental to understand how these elements are regulated and to identify domains involved in the process of retrotransposition. Additionally, the modification of a retrotransposition indicator cassette has allowed developing straightforward approaches to characterize the site of new L1 insertions in cultured cells. In this chapter, we describe a method termed "L1-recovery" that has been used to characterize the site of insertion on engineered L1 retrotransposition events in cultured mammalian cells. Notably, the recovery assay is based on a genetic strategy and avoids the use of PCR and thus reduces to a minimum the appearance of false positives/artifacts.

  17. Tip Characterization Method using Multi-feature Characterizer for CD-AFM

    PubMed Central

    Orji, Ndubuisi G.; Itoh, Hiroshi; Wang, Chumei; Dixson, Ronald G.; Walecki, Peter S.; Schmidt, Sebastian W.; Irmer, Bernd

    2016-01-01

    In atomic force microscopy (AFM) metrology, the tip is a key source of uncertainty. Images taken with an AFM show a change in feature width and shape that depends on tip geometry. This geometric dilation is more pronounced when measuring features with high aspect ratios, and makes it difficult to obtain absolute dimensions. In order to accurately measure nanoscale features using an AFM, the tip dimensions should be known with a high degree of precision. We evaluate a new AFM tip characterizer, and apply it to critical dimension AFM (CD-AFM) tips used for high aspect ratio features. The characterizer is made up of comb-shaped lines and spaces, and includes a series of gratings that could be used as an integrated nanoscale length reference. We also demonstrate a simulation method that could be used to specify what range of tip sizes and shapes the characterizer can measure. Our experiments show that for non re-entrant features, the results obtained with this characterizer are consistent to 1 nm with the results obtained by using widely accepted but slower methods that are common practice in CD-AFM metrology. A validation of the integrated length standard using displacement interferometry indicates a uniformity of better than 0.75%, suggesting that the sample could be used as highly accurate and SI traceable lateral scale for the whole evaluation process. PMID:26720439

  18. Characterization of nutraceuticals and functional foods by innovative HPLC methods.

    PubMed

    Corradini, Claudio; Galanti, Roberta; Nicoletti, Isabella

    2002-04-01

    In recent years there is a growing interest in food and food ingredient which may provide health benefits. Food as well as food ingredients containing health-preserving components, are not considered conventional food, but can be defined as functional food. To characterise such foods, as well as nutraceuticals specific, high sensitive and reproducible analytical methodologies are needed. In light of this importance we set out to develop innovative HPLC methods employing reversed phase narrow bore column and high-performance anion-exchange chromatographic methods coupled with pulsed amperometric detection (HPAEC-PAD), which are specific for carbohydrate analysis. The developed methods were applied for the separation and quantification of citrus flavonoids and to characterize fructooligosaccharide (FOS) and fructans added to functional foods and nutraceuticals.

  19. Total Gamma Count Rate Analysis Method for Nondestructive Assay Characterization

    SciTech Connect

    Cecilia R. Hoffman; Yale D. Harker

    2006-03-01

    A new approach to nondestructively characterize waste for disposal, based on total gamma response, has been developed at the Idaho Cleanup Project by CH2M-WG Idaho, LLC and Idaho State University, and is called the total gamma count rate analysis method. The total gamma count rate analysis method measures gamma interactions that produce energetic electrons or positrons in a detector. Based on previous experience with waste assays, the radionuclide content of the waste container is then determined. This approach potentially can yield minimum detection limits of less than 10 nCi/g. The importance of this method is twofold. First, determination of transuranic activity can be made for waste containers that are below the traditional minimum detection limits. Second, waste above 10 nCi/g and below 100 nCi/g can be identified, and a potential path for disposal resolved.

  20. Molecular Diagnostic Methods for Detection and Characterization of Human Noroviruses

    PubMed Central

    Chen, Haifeng; Hu, Yuan

    2016-01-01

    Human noroviruses are a group of viral agents that afflict people of all age groups. The viruses are now recognized as the most common causative agent of nonbacterial acute gastroenteritis and foodborne viral illness worldwide. However, they have been considered to play insignificant roles in the disease burden of acute gastroenteritis for the past decades until the recent advent of new and more sensitive molecular diagnostic methods. The availability and application of the molecular diagnostic methods have led to enhanced detection of noroviruses in clinical, food and environmental samples, significantly increasing the recognition of noroviruses as an etiologic agent of epidemic and sporadic acute gastroenteritis. This article aims to summarize recent efforts made for the development of molecular methods for the detection and characterization of human noroviruses. PMID:27335620

  1. A novel method for material characterization of reusable products.

    PubMed

    Fortuna, Lorena M; Diyamandoglu, Vasil

    2016-06-01

    Product reuse contributes favorably to waste management and resource recovery by diverting products from terminal disposal to second-hand urban markets. Many organizations with social mission incorporate in their activities the process of reuse, thus making valuable products available to second-hand customers through their thrift stores. Data management and product classification are an important aspect of quantitative analysis of second-hand products circulating through reuse organizations. The New York City Center for Materials Reuse has, for the last 10years, organized the reuse activities of most not for profit organizations, and collected valuable information on the strengths and weaknesses of their operations. One such finding is the casual, and inconsistent approach used by these organizations to keep a record of the level and value of the reuse efforts they undertake. This paper describes a novel methodology developed to standardize record keeping and characterize commonly reused post-consumer products by assessing the outgoing product flow from reuse organizations. The approach groups material composition of individual products into main product categories, creating a simplified method to characterize products. Furthermore, by linking product categories and material composition, the method creates a matrix to help identify the material composition of products handled by reuse organizations. As part of the methodology, whenever adequate data are not available about certain types of products, a process identified as "field characterization study" is proposed and incorporated in the implementation to develop meaningful and useful data on the weight and material composition. Finally, the method incorporates the estimation of the environmental impact of reuse using standard models available through the U.S. Environmental Protection Agency and other worldwide entities. The diversified weight and size of products poses a challenge to the statistical significance

  2. Non-contact method for characterization of a rotational table

    NASA Astrophysics Data System (ADS)

    La Moure Shattuck, Judson, III; Parisi, Vincent M.; Smerdon, Arryn J.

    2007-04-01

    The United States Air Force (USAF) uses and evaluates a variety of helmet-mounted trackers for incorporation into their high performance aircraft. The primary head tracker technologies commercially available are magnetic trackers, inertial trackers, and optical trackers. Each head tracker has a unique method of determining the pilot's head position within the cockpit of the aircraft. Magnetic trackers generally have a small head mounted size and minimal head weight. Because they sense a generated magnetic field, their accuracy can be affected by other magnetic fields or ferrous components within the cockpit. Inertial trackers cover the entire head motion box but require constant motion in order to accommodate drifting of the inertial sensors or a secondary system that updates the inertial system, often referred to as a hybrid system. Although optical head trackers (OHT) are immune to magnetic fields some of their limitations may be daylight/night vision goggle (NVG) compatibility issues and, depending on system configuration, may require numerous emitters and/or receivers to cover a large head motion box and provide a wide field of regard. The Dynamic Tracker Test Fixture (DTTF) was designed by the Helmet Mounted Sensory Technology (HMST) laboratory to accurately measure azimuth rotation in both static and dynamic conditions for the purpose of determining the accuracy of a variety of head trackers. Before the DTTF could be used as an evaluation tool, it required characterization to determine the amount and location of any induced elevation or roll as the table rotated in azimuth. Optimally, the characterization method would not affect the DTTF's movement so a non-contact method was devised. This paper describes the characterization process and its results.

  3. Apparatus and method for characterizing conductivity of materials

    DOEpatents

    Doss, J.D.

    1988-04-13

    Apparatus and method for noncontact, radio-frequency shielding current characterization of materials. Self- or mutual inductance changes in one or more inductive elements, respectively, occur when materials capable of supporting shielding currents are placed in proximity thereto, or undergo change in resistivity while in place. Such changes can be observed by incorporating the inductor(s) in a resonant circuit and determining the frequency of oscillation or by measuring the voltage induced on a coupled inductive element. The present invention is useful for determining the critical temperature and superconducting transition width for superconducting samples. 8 figs.

  4. Method and apparatus for characterizing reflected ultrasonic pulses

    NASA Technical Reports Server (NTRS)

    Yost, William T. (Inventor); Cantrell, John H., Jr. (Inventor)

    1991-01-01

    The invention is a method of and apparatus for characterizing the amplitudes of a sequence of reflected pulses R1, R2, and R3 by converting them into corresponding electric signals E1, E2, and E3 to substantially the same value during each sequence thereby restoring the reflected pulses R1, R2, and R3 to their initial reflection values by timing means, an exponential generator, and a time gain compensator. Envelope and baseline reject circuits permit the display and accurate location of the time spaced sequence of electric signals having substantially the same amplitude on a measurement scale on a suitable video display or oscilloscope.

  5. Tensor analysis methods for activity characterization in spatiotemporal data

    SciTech Connect

    Haass, Michael Joseph; Van Benthem, Mark Hilary; Ochoa, Edward M.

    2014-03-01

    Tensor (multiway array) factorization and decomposition offers unique advantages for activity characterization in spatio-temporal datasets because these methods are compatible with sparse matrices and maintain multiway structure that is otherwise lost in collapsing for regular matrix factorization. This report describes our research as part of the PANTHER LDRD Grand Challenge to develop a foundational basis of mathematical techniques and visualizations that enable unsophisticated users (e.g. users who are not steeped in the mathematical details of matrix algebra and mulitway computations) to discover hidden patterns in large spatiotemporal data sets.

  6. Apparatus and method for characterizing ultrafast polarization varying optical pulses

    DOEpatents

    Smirl, Arthur; Trebino, Rick P.

    1999-08-10

    Practical techniques are described for characterizing ultrafast potentially ultraweak, ultrashort optical pulses. The techniques are particularly suited to the measurement of signals from nonlinear optical materials characterization experiments, whose signals are generally too weak for full characterization using conventional techniques.

  7. Statistical Methods for Characterizing Variability in Stellar Spectra

    NASA Astrophysics Data System (ADS)

    Cisewski, Jessi; Yale Astrostatistics

    2017-01-01

    Recent years have seen a proliferation in the number of exoplanets discovered. One technique for uncovering exoplanets relies on the detection of subtle shifts in the stellar spectra due to the Doppler effect caused by an orbiting object. However, stellar activity can cause distortions in the spectra that mimic the imprint of an orbiting exoplanet. The collection of stellar spectra potentially contains more information than is traditionally used for estimating its radial velocity curve. I will discuss some statistical methods that can be used for characterizing the sources of variability in the spectra. Statistical assessment of stellar spectra is a focus of the Statistical and Applied Mathematical Sciences Institute (SAMSI)'s yearlong program on Statistical, Mathematical and Computational Methods for Astronomy's Working Group IV (Astrophysical Populations).

  8. Nondestructive characterization methods for monolithic solid oxide fuel cells

    SciTech Connect

    Ellingson, W.A.

    1993-01-01

    Monolithic solid oxide fuel cells (MSOFCS) represent a potential breakthrough in fuel cell technology, provided that reliable fabrication methods can be developed. Fabrication difficulties arise in several steps of the processing: First is the fabrication of uniform thin (305 {mu}m) single-layer and trilayer green tapes (the trilayer tapes of anode/electrolyte/cathode and anode/interconnect/cathode must have similar coefficients of thermal expansion to sinter uniformly and to have the necessary electrochemical properties); Second is the development of fuel and oxidant channels in which residual stresses are likely to develop in the tapes; Third is the fabrication of a ``complete`` cell for which the bond quality between layers and the quality of the trilayers must be established; and Last, attachment of fuel and oxidant manifolds and verification of seal integrity. Purpose of this report is to assess nondestructive characterization methods that could be developed for application to laboratory, prototype, and full-scale MSOFCs.

  9. Hybrid Solution of Stochastic Optimal Control Problems Using Gauss Pseudospectral Method and Generalized Polynomial Chaos Algorithms

    DTIC Science & Technology

    2012-03-01

    rem for a minimum. Bolza and Bliss built upon Weierstrass’ work at the University of Chicago giving CV its current rigorous mathematical structure...M. S. “Recent Advances in Non- Intrusive Polynomial Chaos and Stochas- tic Collocation Methods for Uncertainty Analysis and Design”. 50th AIAA/AS- ME

  10. A method for distinctly marking honey bees, Apis mellifera originating from multiple apiary locations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Inexpensive and non-intrusive marking methods are essential to track natural behavior of insects for biological experiments. An inexpensive, easy to construct, and easy to install bee marking device is described. The device is mounted at the entrance of a standard honey bee, Apis mellifera L. (Hymen...

  11. Characterization of peak flow events with local singularity method

    NASA Astrophysics Data System (ADS)

    Cheng, Q.; Li, L.; Wang, L.

    2009-07-01

    Three methods, return period, power-law frequency plot (concentration-area) and local singularity index, are introduced in the paper for characterizing peak flow events from river flow data for the past 100 years from 1900 to 2000 recorded at 25 selected gauging stations on rivers in the Oak Ridges Moraine (ORM) area, Canada. First a traditional method, return period, was applied to the maximum annual river flow data. Whereas the Pearson III distribution generally fits the values, a power-law frequency plot (C-A) on the basis of self-similarity principle provides an effective mean for distinguishing "extremely" large flow events from the regular flow events. While the latter show a power-law distribution, about 10 large flow events manifest departure from the power-law distribution and these flow events can be classified into a separate group most of which are related to flood events. It is shown that the relation between the average water releases over a time period after flow peak and the time duration may follow a power-law distribution. The exponent of the power-law or singularity index estimated from this power-law relation may be used to characterize non-linearity of peak flow recessions. Viewing large peak flow events or floods as singular processes can anticipate the application of power-law models not only for characterizing the frequency distribution of peak flow events, for example, power-law relation between the number and size of floods, but also for describing local singularity of processes such as power-law relation between the amount of water released versus releasing time. With the introduction and validation of singularity of peak flow events, alternative power-law models can be used to depict the recession property as well as other types of non-linear properties.

  12. Physical and chemical methods for the characterization of hazardous wastes

    NASA Astrophysics Data System (ADS)

    Francis, C. W.; Maskarinec, M. P.; Lee, D. W.

    Numerous test methods have been proposed and developed to evaluate the hazards associated with handling and disposal of wastes in landfills. The major concern is the leaching of toxic constituents from the wastes. The fate of hazardous constituents in landfilled wastes is highly dependent on the physical and chemical characteristics of the waste. Thus, the primary objective in the selection of waste characterization procedures should be focused on those methods that gauge the fate of the waste's hazardous constituents in a specific landfill environment. Waste characterization in the United States has centered around the characteristics of ignitability, corrosivity, reactivity, and toxicity. The strategy employed in the development of most regulatory waste characterization procedures has been a pass or fail approach, usually tied to some form of a mismanagement scenario for that waste. For example, USEPA has chosen the disposal of a waste in a municipal waste landfill as a mismanagement scenario for the development of the waste leaching tests to determine the toxicity characteristic. Many wastes, such as large-volume utility wastes or mining wastes, are not disposed of in municipal waste landfills. As a consequence, more effort is needed in the development of waste leaching tests that determine the long-term leaching characteristics of that waste in the landfill environment in which the waste is to be disposed. Waste leaching models also need to be developed and tested as to their ability to simulate actual disposal environments. These models need to be compared with laboratory leaching tests, and, if practical, coupled with groundwater transport models.

  13. Characterizing Awake and Anesthetized States Using a Dimensionality Reduction Method.

    PubMed

    Mirsadeghi, M; Behnam, H; Shalbaf, R; Jelveh Moghadam, H

    2016-01-01

    Distinguishing between awake and anesthetized states is one of the important problems in surgery. Vital signals contain valuable information that can be used in prediction of different levels of anesthesia. Some monitors based on electroencephalogram (EEG) such as the Bispectral (BIS) index have been proposed in recent years. This study proposes a new method for characterizing between awake and anesthetized states. We validated our method by obtaining data from 25 patients during the cardiac surgery that requires cardiopulmonary bypass. At first, some linear and non-linear features are extracted from EEG signals. Then a method called "LLE"(Locally Linear Embedding) is used to map high-dimensional features in a three-dimensional output space. Finally, low dimensional data are used as an input to a quadratic discriminant analyzer (QDA). The experimental results indicate that an overall accuracy of 88.4 % can be obtained using this method for classifying the EEG signal into conscious and unconscious states for all patients. Considering the reliability of this method, we can develop a new EEG monitoring system that could assist the anesthesiologists to estimate the depth of anesthesia accurately.

  14. Synthesis and characterization of iron orthophosphate by solution combustion method

    SciTech Connect

    Baykan, Demet; Oztas, Nursen Altuntas

    2012-12-15

    Graphical abstract: Display Omitted Highlights: ► Solution combustion synthesis was firstly employed to prepare FePO{sub 4}. ► Pure, well-crystallized and porous FePO{sub 4} was obtained and characterized. ► The results proved SCS a time saving and practically applicable method. -- Abstract: The present work applies solution combustion synthesis (SCS) by employing glycine as organic fuel to stimulate the synthesis of pure iron orthophosphate with well-defined reaction parameters. The structural and morphological properties of the products were characterized and confirmed by powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and surface analyzer, respectively. Thermal behaviors were also investigated by TG/DT analyses. The optimal condition was set at 500 °C in a few minutes, giving pure iron orthophosphate with a good level of crystallinity and 11,769 m{sup 2}/g surface area. The results proved SCS a time saving and practically applicable method.

  15. Hydrogeological-Geophysical Methods for Subsurface Site Characterization - Final Report

    SciTech Connect

    Rubin, Yoram

    2001-01-01

    The goal of this research project is to increase water savings and show better ecological control of natural vegetation by developing hydrogeological-geophysical methods for characterizing the permeability and content of water in soil. The ground penetrating radar (GPR) tool was developed and used as the surface geophysical method for monitoring water content. Initial results using the tool suggest that surface GPR is a viable technique for obtaining precision volumetric water content profile estimates, and that laboratory-derived petrophysical relationships could be applied to field-scale GPR data. A field-scale bacterial transport study was conducted within an uncontaminated sandy Pleistocene aquifer to evaluate the importance of heterogeneity in controlling the transport of bacteria. Geochemical, hydrological, geological, and geophysical data were collected to characterize the site prior to and after chemical and bacterial injection experiments. Study results shows that, even within the fairly uniform shallow marine deposits of the narrow channel focus area, heterogeneity existed that influenced the chemical tracer transport over lateral distances of a few meters and vertical distances of less than a half meter. The interpretation of data suggest that the incorporation of geophysical data with limited hydrological data may provide valuable information about the stratigraphy, log conductivity values, and the spatial correlation structure of log conductivity, which have traditionally been obtainable only by performing extensive and intrusive hydrological sampling.

  16. Method to characterize dielectric properties of powdery substances

    NASA Astrophysics Data System (ADS)

    Tuhkala, M.; Juuti, J.; Jantunen, H.

    2013-07-01

    An open ended coaxial cavity method for dielectric characterization of powdery substance operating at 4.5 GHz in TEM mode is presented. Classical mixing rules and electromagnetic modeling were utilized with measured effective permittivities and Q factors to determine the relative permittivity and dielectric loss tangent of different powders with ɛr up to 30. The modeling enabled determination of the correction factor for the simplified equation for the relative permittivity of an open ended coaxial resonator and mixing rules having the best correlation with experiments. SiO2, Al2O3, LTCC CT 2000, ZrO2, and La2O3 powders were used in the experiments. Based on the measured properties and Bruggeman symmetric and Looyenga mixing rules, the determined dielectric characteristics of the powders exhibited good correlation with values in the literature. The presented characterization method enabled the determination of dielectric properties of powdery substances within the presented range, and therefore could be applied to various research fields and applications where dielectric properties of powders need to be known and controlled.

  17. Amyloid oligomer structure characterization from simulations: A general method

    SciTech Connect

    Nguyen, Phuong H.; Li, Mai Suan

    2014-03-07

    Amyloid oligomers and plaques are composed of multiple chemically identical proteins. Therefore, one of the first fundamental problems in the characterization of structures from simulations is the treatment of the degeneracy, i.e., the permutation of the molecules. Second, the intramolecular and intermolecular degrees of freedom of the various molecules must be taken into account. Currently, the well-known dihedral principal component analysis method only considers the intramolecular degrees of freedom, and other methods employing collective variables can only describe intermolecular degrees of freedom at the global level. With this in mind, we propose a general method that identifies all the structures accurately. The basis idea is that the intramolecular and intermolecular states are described in terms of combinations of single-molecule and double-molecule states, respectively, and the overall structures of oligomers are the product basis of the intramolecular and intermolecular states. This way, the degeneracy is automatically avoided. The method is illustrated on the conformational ensemble of the tetramer of the Alzheimer's peptide Aβ{sub 9−40}, resulting from two atomistic molecular dynamics simulations in explicit solvent, each of 200 ns, starting from two distinct structures.

  18. Novel analytical methods for the characterization of oral wafers.

    PubMed

    Garsuch, Verena; Breitkreutz, Jörg

    2009-09-01

    This study aims at compensating the lack of adequate methods for the characterization of the novel dosage forms buccal wafers by applying recent advanced analytical techniques. Fast-dissolving oral wafers need special methods for assessing their properties in drug development and quality control. For morphologic investigations, scanning electron microscopy (SEM) and near-infrared chemical imaging (NIR-CI) were used. Differences in the distribution of the active pharmaceutical ingredient within wafers can be depicted by NIR-CI. Film thickness was determined by micrometer screw and coating thickness gauge revealing no significant differences between the obtained values. To distinguish between the mechanical properties of different polymers, tensile test was performed. Suitable methods to predict disintegration behaviour are thermomechanical analysis and contact angle measurement. The determination of drug release was carried out by three different methods. Fibre-optic sensor systems allow an online measurement of the drug release profiles and the thorough analysis even within the first seconds of disintegration and drug dissolution.

  19. Amyloid oligomer structure characterization from simulations: A general method

    NASA Astrophysics Data System (ADS)

    Nguyen, Phuong H.; Li, Mai Suan; Derreumaux, Philippe

    2014-03-01

    Amyloid oligomers and plaques are composed of multiple chemically identical proteins. Therefore, one of the first fundamental problems in the characterization of structures from simulations is the treatment of the degeneracy, i.e., the permutation of the molecules. Second, the intramolecular and intermolecular degrees of freedom of the various molecules must be taken into account. Currently, the well-known dihedral principal component analysis method only considers the intramolecular degrees of freedom, and other methods employing collective variables can only describe intermolecular degrees of freedom at the global level. With this in mind, we propose a general method that identifies all the structures accurately. The basis idea is that the intramolecular and intermolecular states are described in terms of combinations of single-molecule and double-molecule states, respectively, and the overall structures of oligomers are the product basis of the intramolecular and intermolecular states. This way, the degeneracy is automatically avoided. The method is illustrated on the conformational ensemble of the tetramer of the Alzheimer's peptide Aβ9-40, resulting from two atomistic molecular dynamics simulations in explicit solvent, each of 200 ns, starting from two distinct structures.

  20. Amyloid oligomer structure characterization from simulations: a general method.

    PubMed

    Nguyen, Phuong H; Li, Mai Suan; Derreumaux, Philippe

    2014-03-07

    Amyloid oligomers and plaques are composed of multiple chemically identical proteins. Therefore, one of the first fundamental problems in the characterization of structures from simulations is the treatment of the degeneracy, i.e., the permutation of the molecules. Second, the intramolecular and intermolecular degrees of freedom of the various molecules must be taken into account. Currently, the well-known dihedral principal component analysis method only considers the intramolecular degrees of freedom, and other methods employing collective variables can only describe intermolecular degrees of freedom at the global level. With this in mind, we propose a general method that identifies all the structures accurately. The basis idea is that the intramolecular and intermolecular states are described in terms of combinations of single-molecule and double-molecule states, respectively, and the overall structures of oligomers are the product basis of the intramolecular and intermolecular states. This way, the degeneracy is automatically avoided. The method is illustrated on the conformational ensemble of the tetramer of the Alzheimer's peptide Aβ9-40, resulting from two atomistic molecular dynamics simulations in explicit solvent, each of 200 ns, starting from two distinct structures.

  1. Impulse response method for characterization of echogenic liposomesa)

    PubMed Central

    Raymond, Jason L.; Luan, Ying; van Rooij, Tom; Kooiman, Klazina; Huang, Shao-Ling; McPherson, David D.; Versluis, Michel; de Jong, Nico; Holland, Christy K.

    2015-01-01

    An optical characterization method is presented based on the use of the impulse response to characterize the damping imparted by the shell of an air-filled ultrasound contrast agent (UCA). The interfacial shell viscosity was estimated based on the unforced decaying response of individual echogenic liposomes (ELIP) exposed to a broadband acoustic impulse excitation. Radius versus time response was measured optically based on recordings acquired using an ultra-high-speed camera. The method provided an efficient approach that enabled statistical measurements on 106 individual ELIP. A decrease in shell viscosity, from 2.1 × 10−8 to 2.5 × 10−9 kg/s, was observed with increasing dilatation rate, from 0.5 × 106 to 1 × 107 s−1. This nonlinear behavior has been reported in other studies of lipid-shelled UCAs and is consistent with rheological shear-thinning. The measured shell viscosity for the ELIP formulation used in this study [κs = (2.1 ± 1.0) × 10−8 kg/s] was in quantitative agreement with previously reported values on a population of ELIP and is consistent with other lipid-shelled UCAs. The acoustic response of ELIP therefore is similar to other lipid-shelled UCAs despite loading with air instead of perfluorocarbon gas. The methods described here can provide an accurate estimate of the shell viscosity and damping for individual UCA microbubbles. PMID:25920822

  2. Spectroscopic Methods of Remote Sensing for Vegetation Characterization

    NASA Astrophysics Data System (ADS)

    Kokaly, R. F.

    2013-12-01

    Imaging spectroscopy (IS), often referred to as hyperspectral remote sensing, is one of the latest innovations in a very long history of spectroscopy. Spectroscopic methods have been used for understanding the composition of the world around us, as well as, the solar system and distant parts of the universe. Continuous sampling of the electromagnetic spectrum in narrow bands is what separates IS from previous forms of remote sensing. Terrestrial imaging spectrometers often have hundreds of channels that cover the wavelength range of reflected solar radiation, including the visible, near-infrared (NIR), and shortwave infrared (SWIR) regions. In part due to the large number of channels, a wide variety of methods have been applied to extract information from IS data sets. These can be grouped into several broad classes, including: multi-channel indices, statistical procedures, full spectrum mixing models, and spectroscopic methods. Spectroscopic methods carry on the more than 150 year history of laboratory-based spectroscopy applied to material identification and characterization. Spectroscopic methods of IS relate the positions and shapes of spectral features resolved by airborne and spaceborne sensors to the biochemical and physical composition of vegetation in a pixel. The chlorophyll 680nm, water 980nm, water 1200nm, SWIR 1700nm, SWIR 2100nm, and SWIR 2300nm features have been the subject of study. Spectral feature analysis (SFA) involves isolating such an absorption feature using continuum removal (CR) and calculating descriptors of the feature, such as center position, depth, width, area, and asymmetry. SFA has been applied to quantify pigment and non-pigment biochemical concentrations in leaves, plants, and canopies. Spectral feature comparison (SFC) utilizes CR of features in each pixel's spectrum and linear regression with continuum-removed features in reference spectra in a library of known vegetation types to map vegetation species and communities. SFC has

  3. Raman spectroscopic instrumentation and plasmonic methods for material characterization

    NASA Astrophysics Data System (ADS)

    Tanaka, Kazuki

    The advent of nanotechnology has led to incredible growth in how we consume, make and approach advanced materials. By exploiting nanoscale material properties, unique control of optical, thermal, mechanical, and electrical characteristics becomes possible. This thesis describes the development of a novel localized surface plasmon resonant (LSPR) color sensitive photosensor, based on functionalization of gold nanoparticles onto tianium dioxide nanowires and sensing by a metal-semiconducting nanowire-metal photodiode structure. This LSPR photosensor has been integrated into a system that incorporates Raman spectroscopy, microfluidics, optical trapping, and sorting flow cytometry into a unique material characterization system called the microfluidic optical fiber trapping Raman sorting flow cytometer (MOFTRSFC). Raman spectroscopy is utilized as a powerful molecular characterization technique used to analyze biological, mineralogical and nanomaterial samples. To combat the inherently weak Raman signal, plasmonic methods have been applied to exploit surface enhanced Raman scattering (SERS) and localized surface plasmon resonance (LSPR), increasing Raman intensity by up to 5 orders of magnitude. The resultant MOFTRSFC system is a prototype instrument that can effectively trap, analyze, and sort micron-sized dielectric particles and biological cells. Raman spectroscopy has been presented in several modalities, including the development of a portable near-infrared Raman spectrometer and other emerging technologies.

  4. Optofluidic nanotweezer methods for characterizing nanoparticles and viruses (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Erickson, David

    2016-03-01

    Direct measurements of the strength of particle interactions are critical for characterizing the stability and behavior of colloidal and nanoparticle suspensions. Current techniques are limited in their ability to measure pico-newton scale interaction forces on sub-micrometer particles due to signal detection limits, thermal noise, and throughput. We have recently developed a technique for making direct mechanical measurements of the force and work associated with the steric and electrostatic effects that stabilize colloidal nanoparticles. "Nanophotonic Force Microscopy", as we call it, is unique in that it uses statistical methods to provide direct measurements of these forces at the individual particle scale, while still being sufficiently high-throughput to produce meaningful population level data. In this talk I will introduce the technology, it's advantages, and some of the major uses. Specific case studies will include label-free monitoring of binding of individual antibodies onto single viruses and the measurement of the strength of nanoparticle coatings used for steric stabilization.

  5. Methods to Characterize the Oligonucleotide Functionalization of Quantum Dots.

    PubMed

    Weichelt, Richard; Leubner, Susanne; Henning-Knechtel, Anja; Mertig, Michael; Gaponik, Nikolai; Schmidt, Thorsten-Lars; Eychmüller, Alexander

    2016-09-01

    Currently, DNA nanotechnology offers the most programmable, scalable, and accurate route for the self-assembly of matter with nanometer precision into 1, 2, or 3D structures. One example is DNA origami that is well suited to serve as a molecularly defined "breadboard", and thus, to organize various nanomaterials such as nanoparticles into hybrid systems. Since the controlled assembly of quantum dots (QDs) is of high interest in the field of photonics and other optoelectronic applications, a more detailed view on the functionalization of QDs with oligonucleotides shall be achieved. In this work, four different methods are presented to characterize the functionalization of thiol-capped cadmium telluride QDs with oligonucleotides and for the precise quantification of the number of oligonucleotides bound to the QD surface. This study enables applications requiring the self-assembly of semiconductor-oligonucleotide hybrid materials and proves the conjugation success in a simple and straightforward manner.

  6. Novel method for mechanical characterization of polymeric nanofibers

    NASA Astrophysics Data System (ADS)

    Naraghi, Mohammad; Chasiotis, Ioannis; Kahn, Harold; Wen, Yongkui; Dzenis, Yuris

    2007-08-01

    A novel method to perform nanoscale mechanical characterization of highly deformable nanofibers has been developed. A microelectromechanical system (MEMS) test platform with an on-chip leaf-spring load cell that was tuned with the aid of a focused ion beam was built for fiber gripping and force measurement and it was actuated with an external piezoelectric transducer. Submicron scale tensile tests were performed in ambient conditions under an optical microscope. Engineering stresses and strains were obtained directly from images of the MEMS platform, by extracting the relative rigid body displacements of the device components by digital image correlation. The accuracy in determining displacements by this optical method was shown to be better than 50nm. In the application of this method, the mechanical behavior of electrospun polyacrylonitrite nanofibers with diameters ranging from 300to600nm was investigated. The stress-strain curves demonstrated an apparent elastic-perfectly plastic behavior with elastic modulus of 7.6±1.5GPa and large irreversible strains that exceeded 220%. The large fiber stretch ratios were the result of a cascade of periodic necks that formed during cold drawing of the nanofibers.

  7. Applying analytical and experimental methods to characterize engineered components

    NASA Astrophysics Data System (ADS)

    Munn, Brian S.

    A variety of analytical and experimental methods were employed to characterize two very different types of engineered components. The engineered components of interest were monolithic silicon carbide tiles and M12 x 1.75 Class 9.8 steel fasteners. A new application applying the hole drilling technique was developed on monolithic silicon-carbide tiles of varying thicknesses. This work was driven by a need to first develop a reliable method to measure residual stresses and, then, to validate the methodology through characterizing residual stresses on the tiles of interest. The residual stresses measured in all tiles were tensile in nature. The highest residual stresses were measured at the surface, and decreased exponentially. There was also a trend for the residual tensile stresses to decrease with increasing specimen thickness. Thermal-mechanical interactions were successfully analyzed via a one-way, coupled FEA modeled approach. The key input for a successful FEA analysis was an appropriate heat transfer rate. By varying the heat transfer rate in the FEA model and, then, comparing stress output to experimental residual stress values, provided a favorable numerical solution in determining a heat transfer rate. Fatigue behavior of a M12 x 1.75 Class 9.8 steel test fastener was extensively studied through the use of a variety of experimental and analytical techniques. Of particular interest, was the underlying interaction between notch plasticity and overall fatigue behavior. A very large data set of fastener fatigue behavior was generated with respect to mean stress. A series of endurance limit curves were established for different mean stress values ranging from minimal to the yield strength of the steel fastener (0 ≤ sigmam ≤ sigmay). This wide range in mean stress values created a change in notch tip plasticity which caused a local diminishing of the mean stress increasing expected fatigue life. The change in notch plasticity was identified by residual stress

  8. An electromagnetic induction method for underground target detection and characterization

    SciTech Connect

    Bartel, L.C.; Cress, D.H.

    1997-01-01

    An improved capability for subsurface structure detection is needed to support military and nonproliferation requirements for inspection and for surveillance of activities of threatening nations. As part of the DOE/NN-20 program to apply geophysical methods to detect and characterize underground facilities, Sandia National Laboratories (SNL) initiated an electromagnetic induction (EMI) project to evaluate low frequency electromagnetic (EM) techniques for subsurface structure detection. Low frequency, in this case, extended from kilohertz to hundreds of kilohertz. An EMI survey procedure had already been developed for borehole imaging of coal seams and had successfully been applied in a surface mode to detect a drug smuggling tunnel. The SNL project has focused on building upon the success of that procedure and applying it to surface and low altitude airborne platforms. Part of SNL`s work has focused on improving that technology through improved hardware and data processing. The improved hardware development has been performed utilizing Laboratory Directed Research and Development (LDRD) funding. In addition, SNL`s effort focused on: (1) improvements in modeling of the basic geophysics of the illuminating electromagnetic field and its coupling to the underground target (partially funded using LDRD funds) and (2) development of techniques for phase-based and multi-frequency processing and spatial processing to support subsurface target detection and characterization. The products of this project are: (1) an evaluation of an improved EM gradiometer, (2) an improved gradiometer concept for possible future development, (3) an improved modeling capability, (4) demonstration of an EM wave migration method for target recognition, and a demonstration that the technology is capable of detecting targets to depths exceeding 25 meters.

  9. Cavitating vortex characterization based on acoustic signal detection

    NASA Astrophysics Data System (ADS)

    Digulescu, A.; Murgan, I.; Candel, I.; Bunea, F.; Ciocan, G.; Bucur, D. M.; Dunca, G.; Ioana, C.; Vasile, G.; Serbanescu, A.

    2016-11-01

    In hydraulic turbines operating at part loads, a cavitating vortex structure appears at runner outlet. This helical vortex, called vortex rope, can be cavitating in its core if the local pressure is lower that the vaporization pressure. An actual concern is the detection of the cavitation apparition and the characterization of its level. This paper presents a potentially innovative method for the detection of the cavitating vortex presence based on acoustic methods. The method is tested on a reduced scale facility using two acoustic transceivers positioned in ”V” configuration. The received signals were continuously recorded and their frequency content was chosen to fit the flow and the cavitating vortex. Experimental results showed that due to the increasing flow rate, the signal - vortex interaction is observed as modifications on the received signal's high order statistics and bandwidth. Also, the signal processing results were correlated with the data measured with a pressure sensor mounted in the cavitating vortex section. Finally it is shown that this non-intrusive acoustic approach can indicate the apparition, development and the damping of the cavitating vortex. For real scale facilities, applying this method is a work in progress.

  10. Apparatus and method for characterizing ultrafast polarization varying optical pulses

    DOEpatents

    Smirl, A.; Trebino, R.P.

    1999-08-10

    Practical techniques are described for characterizing ultrafast potentially ultraweak, ultrashort optical pulses. The techniques are particularly suited to the measurement of signals from nonlinear optical materials characterization experiments, whose signals are generally too weak for full characterization using conventional techniques. 2 figs.

  11. A spatiotemporal characterization method for the dynamic cytoskeleton

    PubMed Central

    Alhussein, Ghada; Shanti, Aya; Farhat, Ilyas A. H.; Timraz, Sara B. H.; Alwahab, Noaf S. A.; Pearson, Yanthe E.; Martin, Matthew N.; Christoforou, Nicolas

    2016-01-01

    The significant gap between quantitative and qualitative understanding of cytoskeletal function is a pressing problem; microscopy and labeling techniques have improved qualitative investigations of localized cytoskeleton behavior, whereas quantitative analyses of whole cell cytoskeleton networks remain challenging. Here we present a method that accurately quantifies cytoskeleton dynamics. Our approach digitally subdivides cytoskeleton images using interrogation windows, within which box‐counting is used to infer a fractal dimension (D f) to characterize spatial arrangement, and gray value intensity (GVI) to determine actin density. A partitioning algorithm further obtains cytoskeleton characteristics from the perinuclear, cytosolic, and periphery cellular regions. We validated our measurement approach on Cytochalasin‐treated cells using transgenically modified dermal fibroblast cells expressing fluorescent actin cytoskeletons. This method differentiates between normal and chemically disrupted actin networks, and quantifies rates of cytoskeletal degradation. Furthermore, GVI distributions were found to be inversely proportional to D f, having several biophysical implications for cytoskeleton formation/degradation. We additionally demonstrated detection sensitivity of differences in D f and GVI for cells seeded on substrates with varying degrees of stiffness, and coated with different attachment proteins. This general approach can be further implemented to gain insights on dynamic growth, disruption, and structure of the cytoskeleton (and other complex biological morphology) due to biological, chemical, or physical stimuli. © 2016 The Authors. Cytoskeleton Published by Wiley Periodicals, Inc. PMID:27015595

  12. A rotating disk electrokinetic method for characterizing polyelectrolyte pharmaceutical gels.

    PubMed

    Qu, Beibei; Lee, Ping I

    2012-05-01

    Charge groups in polyelectrolyte gels can affect the entrapment and release of ionic drugs as well as influencing the stability of colloidal and nanoparticulate drug delivery systems. An accurate knowledge of gel charge properties is therefore important to the understanding and design of such drug delivery systems. Existing rotating disk method for quantifying the surface potential of flat surfaces is based on the classical electrokinetic model that neglects the effect of surface conductivity and is therefore only applicable to ion-impenetrable hard surfaces. This classical electrokinetic model would be inaccurate for polyelectrolyte gel systems involving ion-penetrable charged layers or "soft" surfaces. In this study, we developed a new rotating disk model for characterizing charge properties of ion penetrable soft surfaces and tested it on polyvinyl alcohol (PVA)/polyacrylic acid (PAA), gelatin, and gelatin/PAA polyelectrolyte gels. In addition to classical electrokinetic parameters, the contribution of surface conductivity known to be very significant for soft and ion-penetrable gel surfaces has been taken into account in this new rotating disk model. Based on this new approach, two rotating gel disks of different radius but with identical gel composition and preparation procedures were employed for determining the gel surface potential and density of fixed charge groups. A comparison of the resulting data with that obtained from existing rotating disk model ignoring the surface conductivity reveals a significant underestimation of the gel surface potential and the density of fixed charge groups by the ion-impenetrable hard surface approach. Our results thus confirm that the contribution of surface conductivity is significant in the electrokinetic characterization of polyelectrolyte gels that can be evaluated with our new rotating disk model.

  13. A Novel Method for Characterizing Spacesuit Mobility through Metabolic Cost

    NASA Technical Reports Server (NTRS)

    McFarland, Shane; Norcross, Jason

    2014-01-01

    Spacesuit mobility has historically been defined and characterized by a combination of range of motion and joint torque of the individual anatomical joints when performing isolated motions meant to drive that joint only in a given orthogonal plane. While this has been the standard approach for several decades, there are numerous shortcomings that suit designers and engineers would like to see rectified. First, the lack of a standardized method for collecting both range of motion and joint torque translates to many different test setups, procedures and methods of data analysis. Second, all of these previously used methods for data collection lack some degree of repeatability, even within the same test setup and the same conductor; in addition, attempts at higher fidelity data collection techniques require high overhead and cost with minimal improvement. Lastly, isolated motions in standard anatomical planes are not representative of real-world tasks that a crewmember would be performing during an EVA, be it microgravity or surface exploration based. To address these shortcomings, options are being explored within the Space Suit and Crew Survival Systems Branch to ascertain the feasibility of an alternative approach to defining mobility - one that is more repeatable, lower overhead, and more tied to functional EVA tasks. This paper serves to document the first attempt at such an alternative option - one that looks at the metabolic energy-cost of a spacesuit. In other words, can we objectively compare the mobility of a spacesuit by evaluating the metabolic cost of that suit to the wearer while performing a battery of functional EVA tasks?

  14. Site characterization for calibration of radiometric sensors using vicarious method

    NASA Astrophysics Data System (ADS)

    Parihar, Shailesh; Rathore, L. S.; Mohapatra, M.; Sharma, A. K.; Mitra, A. K.; Bhatla, R.; Singh, R. S.; Desai, Yogdeep; Srivastava, Shailendra S.

    2016-05-01

    Radiometric performances of earth observation satellite/sensors vary from ground pre-launch calibration campaign to post launch period extended to lifetime of the satellite due to launching vibrations. Therefore calibration is carried out worldwide through various methods throughout satellite lifetime. In India Indian Space Research Organization (ISRO) calibrates the sensor of Resourcesat-2 satellite by vicarious method. One of these vicarious calibration methods is the reflectance-based approach that is applied in this study for radiometric calibration of sensors on-board Resouresat-2 satellite. The results of ground-based measurement of atmospheric conditions and surface reflectance are made at Bap, Rajasthan Calibration/Validation (Cal/Val) site. Cal/Val observations at site were carried out with hyper-spectral Spectroradiometer covering spectral range of 350nm- 2500nm for radiometric characterization of the site. The Sunphotometer/Ozonometer for measuring the atmospheric parameters has also been used. The calibrated radiance is converted to absolute at-sensor spectral reflectance and Top-Of-Atmosphere (TOA) radiance. TOA radiance was computed using radiative transfer model `Second simulation of the satellite signal in the solar spectrum' (6S), which can accurately simulate the problems introduced by the presence of the atmosphere along the path from Sun to target (surface) to Sensor. The methodology for band averaged reflectance retrieval and spectral reflectance fitting process are described. Then the spectral reflectance and atmospheric parameters are put into 6S code to predict TOA radiance which compare with Resourcesat-2 radiance. Spectral signature and its reflectance ratio indicate the uniformity of the site. Thus the study proves that the selected site is suitable for vicarious calibration of sensor of Resourcesat-2. Further the study demonstrates the procedure for similar exercise for site selection for Cal/Val analysis of other satellite over India

  15. Molecular methods for identification and characterization of novel papillomaviruses.

    PubMed

    Kocjan, B J; Bzhalava, D; Forslund, O; Dillner, J; Poljak, M

    2015-09-01

    Papillomaviruses (PV) are a remarkably heterogeneous family of small DNA viruses that infect a wide variety of vertebrate species and are aetiologically linked with the development of various neoplastic changes of the skin and mucosal epithelia. Based on nucleotide similarity, PVs are hierarchically classified into genera, species and types. Novel human PV (HPV) types are given a unique number only after the whole genome has been cloned and deposited with the International HPV Reference Center. As of 9 March 2015, 200 different HPV types, belonging to 49 species, had been recognized by the International HPV Reference Center. In addition, 131 animal PV types identified from 66 different animal species exist. Recent advances in molecular techniques have resulted in an explosive increase in the identification of novel HPV types and novel subgenomic HPV sequences in the last few years. Among PV genera, the γ-PV genus has been growing most rapidly in recent years with 80 completely sequenced HPV types, followed by α-PV and β-PV genera that have 65 and 51 recognized HPV types, respectively. We reviewed in detail the contemporary molecular methods most often used for identification and characterization of novel PV types, including PCR, rolling circle amplification and next-generation sequencing. Furthermore, we present a short overview of 12 and 10 novel HPV types recently identified in Sweden and Slovenia, respectively. Finally, an update on the International Human Papillomavirus Reference Center is provided.

  16. Characterization of nuclear graphite elastic properties using laser ultrasonic methods

    NASA Astrophysics Data System (ADS)

    Zeng, Fan W.; Han, Karen; Olasov, Lauren R.; Gallego, Nidia C.; Contescu, Cristian I.; Spicer, James B.

    2015-05-01

    Laser ultrasonic methods have been used to characterize the elastic behaviors of commercially-available and legacy nuclear graphites. Since ultrasonic techniques are sensitive to various aspects of graphite microstructure including preferred grain orientation, microcrack orientation and porosity, laser ultrasonics is a candidate technique for monitoring graphite degradation and structural integrity in environments expected in high-temperature, gas-cooled nuclear reactors. Aspects of materials texture can be assessed by studying ultrasonic wavespeeds as a function of propagation direction and polarization. Shear wave birefringence measurements, in particular, can be used to evaluate elastic anisotropy. In this work, laser ultrasonic measurements of graphite moduli have been made to provide insight into the relationship between the microstructures and the macroscopic stiffnesses of these materials. In particular, laser ultrasonic measurements have been made using laser line sources to produce shear waves with specific polarizations. By varying the line orientation relative to the sample, shear wave birefringence measurements have been recorded. Results from shear wave birefringence measurements show that an isostatically molded graphite, such as PCIB, behaves isotropically, while an extruded graphite, such as H-451, displays significant ultrasonic texture. Graphites have complicated microstructures that depend on the manufacturing processes used, and ultrasonic texture in these materials could originate from grain orientation and preferred microcrack alignment. Effects on material isotropy due to service related microstructural changes are possible and the ultimate aim of this work is to determine the degree to which these changes can be assessed nondestructively using laser ultrasonics measurements.

  17. Characterization of nuclear graphite elastic properties using laser ultrasonic methods

    SciTech Connect

    Zeng, Fan W; Han, Karen; Olasov, Lauren R; Gallego, Nidia C; Contescu, Cristian I; Spicer, James B

    2015-01-01

    Laser ultrasonic methods have been used to characterize the elastic behaviors of commercially-available and legacy nuclear graphites. Since ultrasonic techniques are sensitive to various aspects of graphite microstructure including preferred grain orientation, microcrack orientation and porosity, laser ultrasonics is a candidate technique for monitoring graphite degradation and structural integrity in environments expected in high-temperature, gas-cooled nuclear reactors. Aspects of materials texture can be assessed by studying ultrasonic wavespeeds as a function of propagation direction and polarization. Shear wave birefringence measurements, in particular, can be used to evaluate elastic anisotropy. In this work, laser ultrasonic measurements of graphite moduli have been made to provide insight into the relationship between the microstructures and the macroscopic stiffnesses of these materials. In particular, laser ultrasonic measurements have been made using laser line sources to produce shear waves with specific polarizations. By varying the line orientation relative to the sample, shear wave birefringence measurements have been recorded. Results from shear wave birefringence measurements show that an isostatically molded graphite, such as PCIB, behaves isotropically, while an extruded graphite, such as H-451, displays significant ultrasonic texture. Graphites have complicated microstructures that depend on the manufacturing processes used, and ultrasonic texture in these materials could originate from grain orientation and preferred microcrack alignment. Effects on material isotropy due to service related microstructural changes are possible and the ultimate aim of this work is to determine the degree to which these changes can be assessed nondestructively using laser ultrasonics measurements

  18. Methods for Characterization of Batteries Using Acoustic Interrogation

    NASA Astrophysics Data System (ADS)

    Bhadra, Shoham

    Batteries are a ubiquitous form of electrochemical energy storage, but thus far the methods for measuring the mechanical properties of batteries and their component materials in operando have lagged far behind the methods for measuring the corresponding electrical properties. In this thesis, I demonstrate methods for determining the changes in materials properties of an electrochemical energy storage cell both ex situ and in operando.. I begin by establishing the impact of micro-scale morphology changes on the macro-scale dynamic mechanical response in commercial alkaline AA cells. Using a bounce test, the coefficient of restitution (COR) of the cell is shown to increase non-linearly as a function of state of charge (SOC). I show that the reason for the increase in the COR stems from the spatially-dependent oxidation of the Zn anode, with an initial increase corresponding to the formation of a percolation pathway of ZnO-clad Zn particles spanning the radius of the anode. The subsequent saturation of the COR is shown to result from the ultimate solidification and desiccation of the Zn anode. Building from this, I present a generalized in operando solution for materials characterization in batteries using ultrasonic interrogation. The materials properties of battery components change during charge and discharge, resulting in a change in the sound speed of the materials. By attaching transducers to a battery during cycling and sending ultrasonic pulses through each cell I observe the changes in the time of flight (ToF) of the pulses, both in reflection and transmission. I show that the changes in ToF correspond to both SOC and state of health (SOH) in a variety of battery chemistries and geometries, and detail a corresponding acoustic conservation law model framework. Finally, I perform these electrochemical acoustic time of flight (EAToF) experiments on commercial alkaline AA cells. By correlating the results with energy dispersive x-ray diffraction (EDXRD) data and

  19. Method for microbubble characterization using primary radiation force.

    PubMed

    Vos, Hendrik J; Guidi, Francesco; Boni, Enrico; Tortoli, Piero

    2007-07-01

    Medical ultrasound contrast agents (UCAs) have evolved from straight image enhancers to pathophysiological markers and drug delivery vehicles. However, the exact dynamic behavior of the encapsulated bubbles composing UCAs is still not entirely known. In this article, we propose to characterize full populations of UCAs, by looking at the translational effects of ultrasound radiation force on each bubble in a diluted population. The setup involves a sensitive, fully programmable transmitter/receiver and two unconventional, real-time display modes. Such display modes are used to measure the displacements produced by irradiation at frequencies in the range 2-8 MHz and pressures between 150 kPa and 1.5 MPa. The behavior of individual bubbles freely moving in a water tank is clearly observed, and it is shown that it depends on the bubble physical dimensions as well as on the viscoelastic properties of the encapsulation. A new method also is distilled that estimates the viscoelastic properties of bubble encapsulation by fitting the experimental bubble velocities to values simulated by a numerical model based on the modified Herring equation and the Bjerknes force. The fit results are a shear modulus of 18 MPa and a viscosity of 0.23 Pas for a thermoplastic PVC-AN shell. Phospholipid shell elasticity and friction parameter of the experimental contrast agent are estimated as 0.8 N/m and 1 10(-7) kg/s, respectively (shear modulus of 32 MPa and viscosity of 0.19 Pas, assuming 4-nm shell thickness).

  20. A simplified method for random vibration analysis of structures with random parameters

    NASA Astrophysics Data System (ADS)

    Ghienne, Martin; Blanzé, Claude

    2016-09-01

    Piezoelectric patches with adapted electrical circuits or viscoelastic dissipative materials are two solutions particularly adapted to reduce vibration of light structures. To accurately design these solutions, it is necessary to describe precisely the dynamical behaviour of the structure. It may quickly become computationally intensive to describe robustly this behaviour for a structure with nonlinear phenomena, such as contact or friction for bolted structures, and uncertain variations of its parameters. The aim of this work is to propose a non-intrusive reduced stochastic method to characterize robustly the vibrational response of a structure with random parameters. Our goal is to characterize the eigenspace of linear systems with dynamic properties considered as random variables. This method is based on a separation of random aspects from deterministic aspects and allows us to estimate the first central moments of each random eigenfrequency with a single deterministic finite elements computation. The method is applied to a frame with several Young's moduli modeled as random variables. This example could be expanded to a bolted structure including piezoelectric devices. The method needs to be enhanced when random eigenvalues are closely spaced. An indicator with no additional computational cost is proposed to characterize the ’’proximity” of two random eigenvalues.

  1. Assessing the reliability of nondestructive evaluation methods for damage characterization

    NASA Astrophysics Data System (ADS)

    Aldrin, John C.; Annis, Charles; Sabbagh, Harold A.; Knopp, Jeremy S.; Lindgren, Eric A.

    2014-02-01

    A comprehensive approach to NDE characterization error evaluation is presented that follows the framework of the `ahat-versus-a' model evaluation process for probability of detection (POD) assessment. Before characterization error model building is performed, an intermediate step must evaluate the presence and frequency of several possible classes of poor characterization results. A case study is introduced based on the estimation the length, depth and width of surface breaking cracks using bolt hole eddy current (BHEC) NDE. This study highlights the importance of engineering and statistical expertise in the model-building process to ensure all key effects and possible interactions are addressed.

  2. Nondestructive Method for Bulk Chemical Characterization of Barred Olivine Chondrules

    NASA Astrophysics Data System (ADS)

    Montoya-Perez, M. A.; Cervantes-de la Cruz, K. E.; Ruvalcaba-Sil, J. L.

    2017-02-01

    This work develops a bulk chemical characterization of barred olivine chondrules based on the XRF analysis using a portable equipment at the National Research and Conservation Science Laboratory of Cultural Heritage (LANCIC-IF) in Mexico City.

  3. Computational Methods for Predictive Simulation of Stochastic Turbulence Systems

    DTIC Science & Technology

    2015-11-05

    Enter title and subtitle with volume number and part number, if applicable . On classified documents, enter the title classification in parentheses. 5a...accuracy, and range of applicability of non-intrusive methods, such as stochastic collocation methods, and intrusive techniques, such as stochastic...engineering flows) over a long time interval is not possible within time and resource constraints. Many applications central to predictive CFD today

  4. Airborne and Ground-Based Optical Characterization of Legacy Underground Nuclear Test Sites

    NASA Astrophysics Data System (ADS)

    Vigil, S.; Craven, J.; Anderson, D.; Dzur, R.; Schultz-Fellenz, E. S.; Sussman, A. J.

    2015-12-01

    Detecting, locating, and characterizing suspected underground nuclear test sites is a U.S. security priority. Currently, global underground nuclear explosion monitoring relies on seismic and infrasound sensor networks to provide rapid initial detection of potential underground nuclear tests. While seismic and infrasound might be able to generally locate potential underground nuclear tests, additional sensing methods might be required to further pinpoint test site locations. Optical remote sensing is a robust approach for site location and characterization due to the ability it provides to search large areas relatively quickly, resolve surface features in fine detail, and perform these tasks non-intrusively. Optical remote sensing provides both cultural and surface geological information about a site, for example, operational infrastructure, surface fractures. Surface geological information, when combined with known or estimated subsurface geologic information, could provide clues concerning test parameters. We have characterized two legacy nuclear test sites on the Nevada National Security Site (NNSS), U20ak and U20az using helicopter-, ground- and unmanned aerial system-based RGB imagery and light detection and ranging (lidar) systems. The multi-faceted information garnered from these different sensing modalities has allowed us to build a knowledge base of how a nuclear test site might look when sensed remotely, and the standoff distances required to resolve important site characteristics.

  5. Method for Characterizing and Identifying Task Evoked Pupillary Responses During Varying Workload Levels

    DTIC Science & Technology

    2011-09-01

    Method for Characterizing and Identifying Task Evoked Pupillary Responses During Varying Workload Levels Allan Fong1, Ciara Sibley2, Joseph...have been shown to correlate with increases in mental workload. This paper proposes an automated method for characterizing and identifying task evoked...pupillary responses (TEPR) during various workload levels. This method captures findings and observations from previous TEPR studies in an automated

  6. Site characterization in densely fractured dolomite: Comparison of methods

    USGS Publications Warehouse

    Muldoon, M.; Bradbury, K.R.

    2005-01-01

    One of the challenges in characterizing fractured-rock aquifers is determining whether the equivalent porous medium approximation is valid at the problem scale. Detailed hydrogeologic characterization completed at a small study site in a densely fractured dolomite has yielded an extensive data set that was used to evaluate the utility of the continuum and discrete-fracture approaches to aquifer characterization. There are two near-vertical sets of fractures at the site; near-horizontal bedding-plane partings constitute a third fracture set. Eighteen boreholes, including five coreholes, were drilled to a depth of ???10.6 m. Borehole geophysical logs revealed several laterally extensive horizontal fractures and dissolution zones. Flowmeter and short-interval packer testing identified which of these features were hydraulically important. A monitoring system, consisting of short-interval piezometers and multilevel samplers, was designed to monitor four horizontal fractures and two dissolution zones. The resulting network consisted of >70 sampling points and allowed detailed monitoring of head distributions in three dimensions. Comparison of distributions of hydraulic head - and hydraulic conductivity determined by these two approaches suggests that even in a densely fractured-carbonate aquifer, a characterization approach using traditional long-interval monitoring wells is inadequate to characterize ground water movement for the purposes of regulatory monitoring or site remediation. In addition, traditional multiwell pumping tests yield an average or bulk hydraulic conductivity that is not adequate for predicting rapid ground water travel times through the fracture network, and the pumping test response does not appear to be an adequate tool for assessing whether the porous medium approximation is valid. Copyright ?? 2005 National Ground Water Association.

  7. Site characterization in densely fractured dolomite: comparison of methods.

    PubMed

    Muldoon, Maureen; Bradbury, Ken R

    2005-01-01

    One of the challenges in characterizing fractured-rock aquifers is determining whether the equivalent porous medium approximation is valid at the problem scale. Detailed hydrogeologic characterization completed at a small study site in a densely fractured dolomite has yielded an extensive data set that was used to evaluate the utility of the continuum and discrete-fracture approaches to aquifer characterization. There are two near-vertical sets of fractures at the site; near-horizontal bedding-plane partings constitute a third fracture set. Eighteen boreholes, including five coreholes, were drilled to a depth of approximately 10.6 m. Borehole geophysical logs revealed several laterally extensive horizontal fractures and dissolution zones. Flowmeter and short-interval packer testing identified which of these features were hydraulically important. A monitoring system, consisting of short-interval piezometers and multilevel samplers, was designed to monitor four horizontal fractures and two dissolution zones. The resulting network consisted of >70 sampling points and allowed detailed monitoring of head distributions in three dimensions. Comparison of distributions of hydraulic head and hydraulic conductivity determined by these two approaches suggests that even in a densely fractured-carbonate aquifer, a characterization approach using traditional long-interval monitoring wells is inadequate to characterize ground water movement for the purposes of regulatory monitoring or site remediation. In addition, traditional multiwell pumping tests yield an average or bulk hydraulic conductivity that is not adequate for predicting rapid ground water travel times through the fracture network, and the pumping test response does not appear to be an adequate tool for assessing whether the porous medium approximation is valid.

  8. Method for characterization of the redox condition of cementitious materials

    SciTech Connect

    Almond, Philip M.; Langton, Christine A.; Stefanko, David B.

    2015-12-22

    Disclosed are methods for determining the redox condition of cementitious materials. The methods are leaching methods that utilize an in situ redox indicator that is present in the cementitious materials as formed. The in situ redox indicator leaches from cementitious material and, when the leaching process is carried out under anaerobic conditions can be utilized to determine the redox condition of the material. The in situ redox indicator can exhibit distinct characteristics in the leachate depending upon the redox condition of the indicator.

  9. Methods for characterizing, classifying, and identifying unknowns in samples

    DOEpatents

    Grate, Jay W [West Richland, WA; Wise, Barry M [Manson, WA

    2002-01-01

    Disclosed is a method for taking the data generated from an array of responses from a multichannel instrument, and determining the characteristics of a chemical in the sample without the necessity of calibrating or training the instrument with known samples containing the same chemical. The characteristics determined by the method are then used to classify and identify the chemical in the sample. The method can also be used to quantify the concentration of the chemical in the sample.

  10. Methods for characterizing, classifying, and identifying unknowns in samples

    DOEpatents

    Grate, Jay W.; Wise, Barry M.

    2003-08-12

    Disclosed is a method for taking the data generated from an array of responses from a multichannel instrument, and determining the characteristics of a chemical in the sample without the necessity of calibrating or training the instrument with known samples containing the same chemical. The characteristics determined by the method are then used to classify and identify the chemical in the sample. The method can also be used to quantify the concentration of the chemical in the sample.

  11. Review of geophysical characterization methods used at the Hanford Site

    SciTech Connect

    GV Last; DG Horton

    2000-03-23

    This paper presents a review of geophysical methods used at Hanford in two parts: (1) shallow surface-based geophysical methods and (2) borehole geophysical methods. This review was not intended to be ``all encompassing'' but should represent the vast majority (>90% complete) of geophysical work conducted onsite and aimed at hazardous waste investigations in the vadose zone and/or uppermost groundwater aquifers. This review did not cover geophysical methods aimed at large-scale geologic structures or seismicity and, in particular, did not include those efforts conducted in support of the Basalt Waste Isolation Program. This review focused primarily on the more recent efforts.

  12. Apparatus and method for the characterization of respirable aerosols

    DOEpatents

    Clark, Douglas K.; Hodges, Bradley W.; Bush, Jesse D.; Mishima, Jofu

    2016-05-31

    An apparatus for the characterization of respirable aerosols, including: a burn chamber configured to selectively contain a sample that is selectively heated to generate an aerosol; a heating assembly disposed within the burn chamber adjacent to the sample; and a sampling segment coupled to the burn chamber and configured to collect the aerosol such that it may be analyzed. The apparatus also includes an optional sight window disposed in a wall of the burn chamber such that the sample may be viewed during heating. Optionally, the sample includes one of a Lanthanide, an Actinide, and a Transition metal.

  13. Development of techniques to characterize particulates emitted from gas turbine exhausts

    NASA Astrophysics Data System (ADS)

    Johnson, M. P.; Hilton, M.; Waterman, D. R.; Black, J. D.

    2003-07-01

    Particles emitted from aircraft play a role in the formation of contrails and it is essential to characterize them to understand the physical and chemical processes that are happening. Current methods for measuring aircraft particulate emissions study the reflectance of samples collected in filter papers. A series of experiments to more fully characterize particulates has been performed on a small-scale gas turbine engine. An intrusive sampling system conforming to current ICAO regulations for aircraft emissions was used with a scanning mobility particle sizer (SMPS). Non-intrusive measurements were made using laser induced incandescence (LII) and samples were taken from the exhaust to analyse using a transmission electron microscope. Results obtained from different techniques showed good agreement with each other. As engine power conditions increased, both the SMPS and LII indicated that the mass of soot had decreased. Differences were observed between measurements of diluted and undiluted samples. The mean particle size decreased with dilution but the size distribution became bi-modal. The study has shown how significant the sampling environment is for measuring particulates and careful techniques need to be used to ensure that accurate, consistent results can be obtained.

  14. Physics of enriched uranyl fluoride deposit characterizations using active neutron and gamma interrogation techniques with {sup 252}Cf

    SciTech Connect

    Wyatt, M.S.; Uckan, T.; Mihalczo, J.T.; Valentine, T.E.; Hannon, T.F.

    1998-08-01

    A method was developed and successfully applied to characterize large uranyl fluoride (UO{sub 2}F{sub 21}) deposits at the former Oak Ridge Gaseous Diffusion Plant. These deposits were formed by a wet air in-leakage into the UF{sub 6} process gas lines over a period of years. The resulting UO{sub 2}F{sub 2} is hygroscopic, readily absorbing moisture from the air to form hydrates as UO{sub 2}F{sub 2}-nH{sub 2}O. The ratio of hydrogen to uranium, denoted H/U, can vary from 0--16, and has significant nuclear criticality safety impacts for large deposits. In order to properly formulate the required course of action, a non-intrusive characterization of the distribution of the fissile material within the pipe, its total mass, and amount of hydration was needed. The Nuclear Weapons Identification System (NWIS) previously developed at the Oak Ridge Y-12 Plant for identification of uranium weapons components in storage containers was used to successfully characterize the distribution, hydration, and total mass of these deposits.

  15. Computational Biology Methods for Characterization of Pluripotent Cells.

    PubMed

    Araúzo-Bravo, Marcos J

    2016-01-01

    Pluripotent cells are a powerful tool for regenerative medicine and drug discovery. Several techniques have been developed to induce pluripotency, or to extract pluripotent cells from different tissues and biological fluids. However, the characterization of pluripotency requires tedious, expensive, time-consuming, and not always reliable wet-lab experiments; thus, an easy, standard quality-control protocol of pluripotency assessment remains to be established. Here to help comes the use of high-throughput techniques, and in particular, the employment of gene expression microarrays, which has become a complementary technique for cellular characterization. Research has shown that the transcriptomics comparison with an Embryonic Stem Cell (ESC) of reference is a good approach to assess the pluripotency. Under the premise that the best protocol is a computer software source code, here I propose and explain line by line a software protocol coded in R-Bioconductor for pluripotency assessment based on the comparison of transcriptomics data of pluripotent cells with an ESC of reference. I provide advice for experimental design, warning about possible pitfalls, and guides for results interpretation.

  16. Methods for characterization of mechanical and electrical prosthetic vacuum pumps.

    PubMed

    Komolafe, Oluseeni; Wood, Sean; Caldwell, Ryan; Hansen, Andrew; Fatone, Stefania

    2013-01-01

    Despite increasingly widespread adoption of vacuum-assisted suspension systems in prosthetic clinical practices, there remain gaps in the body of scientific knowledge guiding clinicians' choices of existing products. In this study, we identified important pump-performance metrics and developed techniques to objectively characterize the evacuation performance of prosthetic vacuum pumps. The sensitivity of the proposed techniques was assessed by characterizing the evacuation performance of two electrical (Harmony e-Pulse [Ottobock; Duderstadt, Germany] and LimbLogic VS [Ohio Willow Wood; Mt. Sterling, Ohio]) and three mechanical (Harmony P2, Harmony HD, and Harmony P3 [Ottobock]) prosthetic pumps in bench-top testing. Five fixed volume chambers ranging from 33 cm(3) (2 in.(3)) to 197 cm(3) (12 in.(3)) were used to represent different air volume spaces between a prosthetic socket and a liner-clad residual limb. All measurements were obtained at a vacuum gauge pressure of 57.6 kPa (17 inHg). The proposed techniques demonstrated sensitivity to the different electrical and mechanical pumps and, to a lesser degree, to the different setting adjustments of each pump. The sensitivity was less pronounced for the mechanical pumps, and future improvements for testing of mechanical vacuum pumps were proposed. Overall, this study successfully offers techniques feasible as standards for assessing the evacuation performance of prosthetic vacuum pump devices.

  17. Material Characterization methods in InAs/InAsSb Type-II superlattices

    SciTech Connect

    Kadlec, Emil Andrew

    2016-12-01

    This document presents a thesis proposal with three topics. It describes an in-depth comparison of lifetime measurement methods for material characterization of InAs/InAsSb type-II superlattices; develops a characterization method based on the 2nd harmonic of a modulated carrier density; and relates lifetime measurements to device performance.

  18. Method for hygromechanical characterization of graphite/epoxy composite

    NASA Technical Reports Server (NTRS)

    Yaniv, Gershon; Peimanidis, Gus; Daniel, Isaac M.

    1987-01-01

    An experimental method is described for measuring hygroscopic swelling strains and mechanical strains of moisture-conditioned composite specimens. The method consists of embedding encapsulated strain gages in the midplane of the composite laminate; thus it does not interfere with normal moisture diffusion. It is particularly suited for measuring moisture swelling coefficients and for mechanical testing of moisture-conditioned specimens at high strain rates. Results obtained by the embedded gage method were shown to be more reliable and reproducible than those obtained by surface gages, dial gages, or extensometers.

  19. A Fast Method of Fully Characterizing Sputtering Angular Dependence (Preprint)

    DTIC Science & Technology

    2008-06-17

    A new method has been demonstrated in which a single experiment is used to fully define the sputtering angular dependence of a given material. The...profilometry; the full sputtering angular dependence curve is then extracted using a numerical approach.

  20. Development of Methods of Characterizing Coal in Its Plastic State

    NASA Technical Reports Server (NTRS)

    Lloyd, W. G.

    1978-01-01

    Coal in its plastic state (typically 400-460 C) was examined by the isothermal Gieseler plastometry of seven selected coals of widely varying plastic properties. Kinetic models were proposed for the isothermal plastometric curves. Plastic behavior was compared with a variety of laboratory analyses and characterizations of these coals, including classical coal analysis; mineral analysis; microstructural analysis (extractable fractions, surface area measurement, and petrographic analysis); and thermal analysis (thermogravimetric analysis, thermomechanical analysis, and differential scanning calorimetry). The phenomenon of a sharp, large, poorly reproducible exotherm in the differential scanning calorimetric analysis of coking coals was examined. Several coal extrudates show mineral distribution, organic maceral composition and overall calorific value to be little affected by 800 F extrusion. Volatile matter and plastic properties are moderately reduced, and the network structure (as gauged by extractables) appears to be slightly degraded in the extrusion process.

  1. Stability Characterization of Quinazoline Derivative BG1188 by Optical Methods

    NASA Astrophysics Data System (ADS)

    Militaru, Andra; Smarandache, Adriana; Mahamoud, Abdallah; Damian, Victor; Ganea, Paul; Alibert, Sandrine; Pagès, Jean-Marie; Pascu, Mihail-Lucian

    2011-08-01

    3-[2-(dimethylamino)ethyl]-6-nitroquinazolin-4(3H)-one, labeled BG1188, is a new synthesized compound, out of a series of quinazoline derivatives developed to fight the multidrug resistance of antibiotics acquired by bacteria. A characterization of the BG1188 powder was made using FTIR spectra in order to evidence the functional groups in the medicine's molecule. The ultraviolet-visible (UV-Vis) absorption spectra were used to study the stability of the BG1188 solutions in two solvents and at different temperatures. BG1188 concentration in ultrapure water was varied between 2×10-3 M (stock solution) and 10-6 M. The concentration recommended by higher activity on bacteria was 10-3 M. For the same reason, this was the utilized concentration of BG1188 in dimethyl sulfoxide (DMSO). Time stability was characterized by comparing the time evolution of the UV-Vis absorption spectra of the BG1188 solutions in ultrapure de-ionized water or in DMSO. The spectra were recorded daily for about 4 months after the preparation for the BG1188 solutions in ultrapure water. Generally, samples are stable within the experimental errors at concentrations higher than 10-5 M, but the stability time interval may vary from 119 days at 10-4 M to 34 days at 10-5 M. Time evolution of the absorption spectra at 10-3 M in ultrapure water shows reproducibility within the measuring errors (±1.045%) for time intervals up to 1032 hours (more than 40 days) after preparation. On the other hand, BG1188 solutions in DMSO may be considered unstable because the absorption spectra modify in terms of peak shapes and intensities, indicating that the samples exhibit modifications immediately after preparation. Regardless the solvent used, some aggregation phenomena took place and wire-like aggregates were observed in all the solutions with the naked eye. These aggregates were analyzed, tentatively, using optical microscopy and FTIR.

  2. Quantitative, Qualitative and Geospatial Methods to Characterize HIV Risk Environments

    PubMed Central

    Conners, Erin E.; West, Brooke S.; Roth, Alexis M.; Meckel-Parker, Kristen G.; Kwan, Mei-Po; Magis-Rodriguez, Carlos; Staines-Orozco, Hugo; Clapp, John D.; Brouwer, Kimberly C.

    2016-01-01

    Increasingly, ‘place’, including physical and geographical characteristics as well as social meanings, is recognized as an important factor driving individual and community health risks. This is especially true among marginalized populations in low and middle income countries (LMIC), whose environments may also be more difficult to study using traditional methods. In the NIH-funded longitudinal study Mapa de Salud, we employed a novel approach to exploring the risk environment of female sex workers (FSWs) in two Mexico/U.S. border cities, Tijuana and Ciudad Juárez. In this paper we describe the development, implementation, and feasibility of a mix of quantitative and qualitative tools used to capture the HIV risk environments of FSWs in an LMIC setting. The methods were: 1) Participatory mapping; 2) Quantitative interviews; 3) Sex work venue field observation; 4) Time-location-activity diaries; 5) In-depth interviews about daily activity spaces. We found that the mixed-methodology outlined was both feasible to implement and acceptable to participants. These methods can generate geospatial data to assess the role of the environment on drug and sexual risk behaviors among high risk populations. Additionally, the adaptation of existing methods for marginalized populations in resource constrained contexts provides new opportunities for informing public health interventions. PMID:27191846

  3. Dynamic characterization of satellite components through non-invasive methods

    SciTech Connect

    Mullens, Joshua G; Wiest, Heather K; Mascarenas, David D; Park, Gyuhae

    2011-01-24

    The rapid deployment of satellites is hindered by the need to flight-qualify their components and the resulting mechanical assembly. Conventional methods for qualification testing of satellite components are costly and time consuming. Furthermore, full-scale vehicles must be subjected to launch loads during testing. The harsh testing environment increases the risk of component damage during qualification. The focus of this research effort was to assess the performance of Structural Health Monitoring (SHM) techniques as replacement for traditional vibration testing. SHM techniques were applied on a small-scale structure representative of a responsive satellite. The test structure consisted of an extruded aluminum space-frame covered with aluminum shear plates, which was assembled using bolted joints. Multiple piezoelectric patches were bonded to the test structure and acted as combined actuators and sensors. Various methods of SHM were explored including impedance-based health monitoring, wave propagation, and conventional frequency response functions. Using these methods in conjunction with finite element modeling, the dynamic properties of the test structure were established and areas of potential damage were identified and localized. The adequacy of the results from each SHM method was validated by comparison to results from conventional vibration testing.

  4. Quantitative, Qualitative and Geospatial Methods to Characterize HIV Risk Environments.

    PubMed

    Conners, Erin E; West, Brooke S; Roth, Alexis M; Meckel-Parker, Kristen G; Kwan, Mei-Po; Magis-Rodriguez, Carlos; Staines-Orozco, Hugo; Clapp, John D; Brouwer, Kimberly C

    2016-01-01

    Increasingly, 'place', including physical and geographical characteristics as well as social meanings, is recognized as an important factor driving individual and community health risks. This is especially true among marginalized populations in low and middle income countries (LMIC), whose environments may also be more difficult to study using traditional methods. In the NIH-funded longitudinal study Mapa de Salud, we employed a novel approach to exploring the risk environment of female sex workers (FSWs) in two Mexico/U.S. border cities, Tijuana and Ciudad Juárez. In this paper we describe the development, implementation, and feasibility of a mix of quantitative and qualitative tools used to capture the HIV risk environments of FSWs in an LMIC setting. The methods were: 1) Participatory mapping; 2) Quantitative interviews; 3) Sex work venue field observation; 4) Time-location-activity diaries; 5) In-depth interviews about daily activity spaces. We found that the mixed-methodology outlined was both feasible to implement and acceptable to participants. These methods can generate geospatial data to assess the role of the environment on drug and sexual risk behaviors among high risk populations. Additionally, the adaptation of existing methods for marginalized populations in resource constrained contexts provides new opportunities for informing public health interventions.

  5. Microbiological characterization of vermicomposts by the method of multisubstrate testing

    NASA Astrophysics Data System (ADS)

    Yakushev, A. V.; Byzov, B. A.

    2008-11-01

    A new modification of the method of multisubstrate testing (MST, BIOLOG) is suggested. It is based on the kinetic description of bacterial growth on nutrient media during 50 h. The results of the MST represent a set of three parameters (the initial optical density, the maximum specific growth rate, and the maximum optical density) of an equation describing the growth of microbial communities on individual substrates. Methods of multivariate statistics (cluster and discriminant analyses) have been used to compare these parameters for 24 organic substrates. It is supposed that a more detailed description of the growth of microorganisms should improve the information capacity of the MST method. The effect of earthworms on vermicomposting has been studied experimentally with the MST method. An empirical rule allowing one to distinguish between vermicomposts and ordinary composts using the results of MST is suggested. Manure, earthy matter from the intestinal tracts of earthworms ( Eisenia andrei), and their coprolites have been subjected to MST. A functional similarity between manure and fresh coprolites has been found. Also, three different lots of industrial vermicomposts have been compared. The cluster analysis has demonstrated a significant difference between them. The clusters depend on the nature of the initial substrates used for preparing these vermicomposts. Thus, unification of the initial substrates used for composting is necessary to obtain standardized vermicomposts.

  6. Dynamic characterization of satellite components through non-invasive methods

    SciTech Connect

    Mullins, Joshua G; Wiest, Heather K; Mascarenas, David D. L.; Macknelly, David

    2010-10-21

    The rapid deployment of satellites is hindered by the need to flight-qualify their components and the resulting mechanical assembly. Conventional methods for qualification testing of satellite components are costly and time consuming. Furthermore, full-scale vehicles must be subjected to launch loads during testing. This harsh testing environment increases the risk of component damage during qualification. The focus of this research effort was to assess the performance of Structural Health Monitoring (SHM) techniques as a replacement for traditional vibration testing. SHM techniques were applied on a small-scale structure representative of a responsive satellite. The test structure consisted of an extruded aluminum space-frame covered with aluminum shear plates, which was assembled using bolted joints. Multiple piezoelectric patches were bonded to the test structure and acted as combined actuators and sensors. Various methods of SHM were explored including impedance-based health monitoring, wave propagation, and conventional frequency response functions. Using these methods in conjunction with finite element modelling, the dynamic properties of the test structure were established and areas of potential damage were identified and localized. The adequacy of the results from each SHM method was validated by comparison to results from conventional vibration testing.

  7. Quantitative methods to characterize morphological properties of cell lines.

    PubMed

    Mancia, Annalaura; Elliott, John T; Halter, Michael; Bhadriraju, Kiran; Tona, Alessandro; Spurlin, Tighe A; Middlebrooks, Bobby L; Baatz, John E; Warr, Gregory W; Plant, Anne L

    2012-07-01

    Descriptive terms are often used to characterize cells in culture, but the use of nonquantitative and poorly defined terms can lead to ambiguities when comparing data from different laboratories. Although recently there has been a good deal of interest in unambiguous identification of cell lines via their genetic markers, it is also critical to have definitive, quantitative metrics to describe cell phenotypic characteristics. Quantitative metrics of cell phenotype will aid the comparison of data from experiments performed at different times and in different laboratories where influences such as the age of the population and differences in culture conditions or protocols can potentially affect cellular metabolic state and gene expression in the absence of changes in the genetic profile. Here, we present examples of robust methodologies for quantitatively assessing characteristics of cell morphology and cell-cell interactions, and of growth rates of cells within the population. We performed these analyses with endothelial cell lines derived from dolphin, bovine and human, and with a mouse fibroblast cell line. These metrics quantify some characteristics of these cells lines that clearly distinguish them from one another, and provide quantitative information on phenotypic changes in one of the cell lines over large number of passages.

  8. Membrane Characterization by Microscopic and Scattering Methods: Multiscale Structure

    PubMed Central

    Tamime, Rahma; Wyart, Yvan; Siozade, Laure; Baudin, Isabelle; Deumie, Carole; Glucina, Karl; Moulin, Philippe

    2011-01-01

    Several microscopic and scattering techniques at different observation scales (from atomic to macroscopic) were used to characterize both surface and bulk properties of four new flat-sheet polyethersulfone (PES) membranes (10, 30, 100 and 300 kDa) and new 100 kDa hollow fibers (PVDF). Scanning Electron Microscopy (SEM) with “in lens” detection was used to obtain information on the pore sizes of the skin layers at the atomic scale. White Light Interferometry (WLI) and Atomic Force Microscopy (AFM) using different scales (for WLI: windows: 900 × 900 μm2 and 360 × 360 μm2; number of points: 1024; for AFM: windows: 50 × 50 μm2 and 5 × 5 μm2; number of points: 512) showed that the membrane roughness increases markedly with the observation scale and that there is a continuity between the different scan sizes for the determination of the RMS roughness. High angular resolution ellipsometric measurements were used to obtain the signature of each cut-off and the origin of the scattering was identified as coming from the membrane bulk. PMID:24957612

  9. Membrane characterization by microscopic and scattering methods: multiscale structure.

    PubMed

    Tamime, Rahma; Wyart, Yvan; Siozade, Laure; Baudin, Isabelle; Deumie, Carole; Glucina, Karl; Moulin, Philippe

    2011-04-13

    Several microscopic and scattering techniques at different observation scales (from atomic to macroscopic) were used to characterize both surface and bulk properties of four new flat-sheet polyethersulfone (PES) membranes (10, 30, 100 and 300 kDa) and new 100 kDa hollow fibers (PVDF). Scanning Electron Microscopy (SEM) with "in lens" detection was used to obtain information on the pore sizes of the skin layers at the atomic scale. White Light Interferometry (WLI) and Atomic Force Microscopy (AFM) using different scales (for WLI: windows: 900 × 900 µm2 and 360 × 360 µm2; number of points: 1024; for AFM: windows: 50 × 50 µm2 and 5 × 5 µm2; number of points: 512) showed that the membrane roughness increases markedly with the observation scale and that there is a continuity between the different scan sizes for the determination of the RMS roughness. High angular resolution ellipsometric measurements were used to obtain the signature of each cut-off and the origin of the scattering was identified as coming from the membrane bulk.

  10. [Characterization of flowability of pharmaceutical powders based on multivariate analysis method].

    PubMed

    Du, Yan; Zhao, Li-Jie; Xiong, Yao-Kun; Li, Xiao-Hai; Wang, Song-Tao; Feng, Yi; Xu, De-Sheng

    2012-09-01

    The main methods of characterizing the flowability of pharmaceutical powders include repose angle method, HR method, Carr's index method, Jenike flow function method, fractal dimension method, and mass flow rate method, etc. Regarding powders with different flowabilities as the research subject, comprehensive features of pharmaceutical materials were investigated and characterized. The multivariate analysis method was employed to evaluate and analyze flowability values of the tested pharmaceutical materials. Comparing with the method of the mass flow rate, it was feasible to use multivariate analysis method to evaluate the flowability of powders. Simultaneously, the flowability of pharmaceutical materials could be ranked and definitely quantified, and critical values be determined according to the actual production, which has promoted the previous methods dependent only on the single parameter, i.e. repose angle and compression degree methods. A relatively objective standard method of evaluating flowability of powders is formed.

  11. Application of Patterson-function direct methods to materials characterization.

    PubMed

    Rius, Jordi

    2014-09-01

    The aim of this article is a general description of the so-called Patterson-function direct methods (PFDM), from their origin to their present state. It covers a 20-year period of methodological contributions to crystal structure solution, most of them published in Acta Crystallographica Section A. The common feature of these variants of direct methods is the introduction of the experimental intensities in the form of the Fourier coefficients of origin-free Patterson-type functions, which allows the active use of both strong and weak reflections. The different optimization algorithms are discussed and their performances compared. This review focuses not only on those PFDM applications related to powder diffraction data but also on some recent results obtained with electron diffraction tomography data.

  12. Characterization of Meta-Materials Using Computational Electromagnetic Methods

    NASA Technical Reports Server (NTRS)

    Deshpande, Manohar; Shin, Joon

    2005-01-01

    An efficient and powerful computational method is presented to synthesize a meta-material to specified electromagnetic properties. Using the periodicity of meta-materials, the Finite Element Methodology (FEM) is developed to estimate the reflection and transmission through the meta-material structure for a normal plane wave incidence. For efficient computations of the reflection and transmission over a wide band frequency range through a meta-material a Finite Difference Time Domain (FDTD) approach is also developed. Using the Nicholson-Ross method and the Genetic Algorithms, a robust procedure to extract electromagnetic properties of meta-material from the knowledge of its reflection and transmission coefficients is described. Few numerical examples are also presented to validate the present approach.

  13. Application of Patterson-function direct methods to materials characterization

    PubMed Central

    Rius, Jordi

    2014-01-01

    The aim of this article is a general description of the so-called Patterson-function direct methods (PFDM), from their origin to their present state. It covers a 20-year period of methodological contributions to crystal structure solution, most of them published in Acta Crystallographica Section A. The common feature of these variants of direct methods is the introduction of the experimental intensities in the form of the Fourier coefficients of origin-free Patterson-type functions, which allows the active use of both strong and weak reflections. The different optimization algorithms are discussed and their performances compared. This review focuses not only on those PFDM applications related to powder diffraction data but also on some recent results obtained with electron diffraction tomography data. PMID:25295171

  14. Review of Physical and Chemical Methods for Characterization of Fuels

    DTIC Science & Technology

    1981-12-01

    Chromatography-New Evaluation Methods of Mathematical Dead Time," Instituto de Quimica Fisica "Rocasolano", Madrid, Spain, Journal of Chromatographic Science...34Separation and Iden- tification of Aldehydes and Ketones From an Irati Oil Shale Bitumen. Use of the Solid Phase Extractor Technique," Instituto de Quimica ...discrepancies possibly caused bydifferences in 2 dynamometer type and ambient conditions. 41. Author Unknown, U.S. Army Test and Evaluation Test Operations

  15. Characterization method of hydrophobic anti-icing coatings

    NASA Astrophysics Data System (ADS)

    Morita, Katsuaki; Sakaue, Hirotaka

    2015-11-01

    For anti-icing, supercooled water should be removed before frozen onto the contact surface. We use a hydrophobic coating for anti-icing and introduce the static- and dynamic-evaluation methods. The methods describe the contact surface between the hydrophobic surface and a supercooled-water droplet. The former is based on the contact angle, and the latter is based on the sliding angle. The temperature factor is included in these models to evaluate the hydrophobic coating under the supercooled conditions. Four hydrophobic coatings are experimentally evaluated based on the static- and dynamic evaluation methods: C1-C3 (commercial fluorocarbon coatings), and Jaxa coating (original fluorocarbon coating). These are evaluated under the supercooled conditions of -10 to 0 °C. The static-evaluation shows variations in the temperature. However, change in the contact angle by the temperature is relatively small compared to that of the sliding angle for the dynamic evaluation. Only C3 and Jaxa coatings are tolerant to the sliding angle under the supercooled conditions tested. The dynamic evaluation shows that even if the coating is hydrophobic, the dynamic evaluation should be included to understand the characteristic of removal for a supercooled-water droplet.

  16. Characterization method of hydrophobic anti-icing coatings.

    PubMed

    Morita, Katsuaki; Sakaue, Hirotaka

    2015-11-01

    For anti-icing, supercooled water should be removed before frozen onto the contact surface. We use a hydrophobic coating for anti-icing and introduce the static- and dynamic-evaluation methods. The methods describe the contact surface between the hydrophobic surface and a supercooled-water droplet. The former is based on the contact angle, and the latter is based on the sliding angle. The temperature factor is included in these models to evaluate the hydrophobic coating under the supercooled conditions. Four hydrophobic coatings are experimentally evaluated based on the static- and dynamic evaluation methods: C1-C3 (commercial fluorocarbon coatings), and Jaxa coating (original fluorocarbon coating). These are evaluated under the supercooled conditions of -10 to 0 °C. The static-evaluation shows variations in the temperature. However, change in the contact angle by the temperature is relatively small compared to that of the sliding angle for the dynamic evaluation. Only C3 and Jaxa coatings are tolerant to the sliding angle under the supercooled conditions tested. The dynamic evaluation shows that even if the coating is hydrophobic, the dynamic evaluation should be included to understand the characteristic of removal for a supercooled-water droplet.

  17. An alternative method to characterize the surface urban heat island.

    PubMed

    Martin, Philippe; Baudouin, Yves; Gachon, Philippe

    2015-07-01

    An urban heat island (UHI) is a relative measure defined as a metropolitan area that is warmer than the surrounding suburban or rural areas. The UHI nomenclature includes a surface urban heat island (SUHI) definition that describes the land surface temperature (LST) differences between urban and suburban areas. The complexity involved in selecting an urban core and external thermal reference for estimating the magnitude of a UHI led us to develop a new definition of SUHIs that excludes any rural comparison. The thermal reference of these newly defined surface intra-urban heat islands (SIUHIs) is based on various temperature thresholds above the spatial average of LSTs within the city's administrative limits. A time series of images from Landsat Thematic Mapper (TM) and Enhanced Thematic Mapper Plus (ETM+) from 1984 to 2011 was used to estimate the LST over the warm season in Montreal, Québec, Canada. Different SIUHI categories were analyzed in consideration of the global solar radiation (GSR) conditions that prevailed before each acquisition date of the Landsat images. The results show that the cumulative GSR observed 24 to 48 h prior to the satellite overpass is significantly linked with the occurrence of the highest SIUHI categories (thresholds of +3 to +7 °C above the mean spatial LST within Montreal city). The highest correlation (≈0.8) is obtained between a pixel-based temperature that is 6 °C hotter than the city's mean LST (SIUHI + 6) after only 24 h of cumulative GSR. SIUHI + 6 can then be used as a thermal threshold that characterizes hotspots within the city. This identification approach can be viewed as a useful criterion or as an initial step toward the development of heat health watch and warning system (HHWWS), especially during the occurrence of severe heat spells across urban areas.

  18. An alternative method to characterize the surface urban heat island

    NASA Astrophysics Data System (ADS)

    Martin, Philippe; Baudouin, Yves; Gachon, Philippe

    2015-07-01

    An urban heat island (UHI) is a relative measure defined as a metropolitan area that is warmer than the surrounding suburban or rural areas. The UHI nomenclature includes a surface urban heat island (SUHI) definition that describes the land surface temperature (LST) differences between urban and suburban areas. The complexity involved in selecting an urban core and external thermal reference for estimating the magnitude of a UHI led us to develop a new definition of SUHIs that excludes any rural comparison. The thermal reference of these newly defined surface intra-urban heat islands (SIUHIs) is based on various temperature thresholds above the spatial average of LSTs within the city's administrative limits. A time series of images from Landsat Thematic Mapper (TM) and Enhanced Thematic Mapper Plus (ETM+) from 1984 to 2011 was used to estimate the LST over the warm season in Montreal, Québec, Canada. Different SIUHI categories were analyzed in consideration of the global solar radiation (GSR) conditions that prevailed before each acquisition date of the Landsat images. The results show that the cumulative GSR observed 24 to 48 h prior to the satellite overpass is significantly linked with the occurrence of the highest SIUHI categories (thresholds of +3 to +7 °C above the mean spatial LST within Montreal city). The highest correlation (≈0.8) is obtained between a pixel-based temperature that is 6 °C hotter than the city's mean LST (SIUHI + 6) after only 24 h of cumulative GSR. SIUHI + 6 can then be used as a thermal threshold that characterizes hotspots within the city. This identification approach can be viewed as a useful criterion or as an initial step toward the development of heat health watch and warning system (HHWWS), especially during the occurrence of severe heat spells across urban areas.

  19. Field methods for rapidly characterizing paint waste during bridge rehabilitation.

    PubMed

    Shu, Zhan; Axe, Lisa; Jahan, Kauser; Ramanujachary, Kandalam V

    2015-09-01

    For Department of Transportation (DOT) agencies, bridge rehabilitation involving paint removal results in waste that is often managed as hazardous. Hence, an approach that provides field characterization of the waste classification would be beneficial. In this study, an analysis of variables critical to the leaching process was conducted to develop a predictive tool for waste classification. This approach first involved identifying mechanistic processes that control leaching. Because steel grit is used to remove paint, elevated iron concentrations remain in the paint waste. As such, iron oxide coatings provide an important surface for metal adsorption. The diffuse layer model was invoked (logKMe=4.65 for Pb and logKMe=2.11 for Cr), where 90% of the data were captured within the 95% confidence level. Based on an understanding of mechanistic processes along with principal component analysis (PCA) of data obtained from field-portable X-ray fluorescence (FP-XRF), statistically-based models for leaching from paint waste were developed. Modeling resulted in 96% of the data falling within the 95% confidence level for Pb (R(2) 0.6-0.9, p ⩽ 0.04), Ba (R(2) 0.5-0.7, p ⩽ 0.1), and Zn (R(2) 0.6-0.7, p ⩽ 0.08). However, the regression model obtained for Cr leaching was not significant (R(2) 0.3-0.5, p ⩽ 0.75). The results of this work may assist DOT agencies with applying a predictive tool in the field that addresses the mobility of trace metals as well as disposal and management of paint waste during bridge rehabilitation.

  20. Risk-Informed Safety Margin Characterization Methods Development Work

    SciTech Connect

    Smith, Curtis L; Ma, Zhegang; Riley, Tom; Mandelli, Diego; Nielsen, Joseph W; Alfonsi, Andrea; Rabiti, Cristian

    2014-09-01

    This report summarizes the research activity developed during the Fiscal year 2014 within the Risk Informed Safety Margin and Characterization (RISMC) pathway within the Light Water Reactor Sustainability (LWRS) campaign. This research activity is complementary to the one presented in the INL/EXT-??? report which shows advances Probabilistic Risk Assessment Analysis using RAVEN and RELAP-7 in conjunction to novel flooding simulation tools. Here we present several analyses that prove the values of the RISMC approach in order to assess risk associated to nuclear power plants (NPPs). We focus on simulation based PRA which, in contrast to classical PRA, heavily employs system simulator codes. Firstly we compare, these two types of analyses, classical and RISMC, for a Boiling water reactor (BWR) station black out (SBO) initiating event. Secondly we present an extended BWR SBO analysis using RAVEN and RELAP-5 which address the comments and suggestions received about he original analysis presented in INL/EXT-???. This time we focus more on the stochastic analysis such probability of core damage and on the determination of the most risk-relevant factors. We also show some preliminary results regarding the comparison between RELAP5-3D and the new code RELAP-7 for a simplified Pressurized Water Reactors system. Lastly we present some conceptual ideas regarding the possibility to extended the RISMC capabilities from an off-line tool (i.e., as PRA analysis tool) to an online-tool. In this new configuration, RISMC capabilities can be used to assist and inform reactor operator during real accident scenarios.

  1. Relationship of roughness of building stones on the effective thermal conductivity determined by transient hot-wire method

    NASA Astrophysics Data System (ADS)

    Benoit, Merckx; Jean-Didier, Mertz; Patrick, Dudoignon; David, Giovannacci; Jean-Philippe, Garnier

    2013-04-01

    Alteration of inorganic materials in monuments is mainly related to relative humidity change in the porous network. Characterization of water content is a complex issue, specially in case of non-intrusive measurement. An innovative method is developed to quantify the water content using a direct calculation of the thermal conductivity. In order to validate the non-intrusive application to heritage stone, a control of the influence of the rock-sensor interface is required. The study was carried out on five sedimentary french rocks : three limestones (lithographic, oolithic and micritic), a sandstone of Fontainebleau and the so-called Tuffeau limestone. The textural properties are characterized by optical and electronical microscopy, X-ray diffraction, and mercury intrusion porosimetry. The transient hot-wire method is useful to obtain a quick value of effective conductivity of material. Initially used in liquids and gas, It's now more and more used for solid materials. The calculation of one effective thermal conductivity is formulated by the slope of recorded DT/ln(t) diagrams. In case of continuous and homogeneous media, only one slope can be measured. For heterogeneous solids a typical curve present two slopes : the first one measured in the short time acquisitions (<1s) mainly depends on the contact between the wire and grains and thus micro texture of the material. The second one, measured for longer time acquisitions, characterizes the mean effective thermal conductivity of the material. In the case of surface measurement, the first part of curve is relevant from the texture and roughness of the material. Roughness properties are determined by an interferometer system on different polished surfaces of the materials. For all studied stones, the arithmetic average roughness (Sa) is ranged between 44 µm and 1 µm, respectively for the coarse-grained limestone (Bretigny) and the finest one (Migné). According to the relative error of the apparatus (10%), the

  2. Characterization of the Space Shuttle Ascent Debris using CFD Methods

    NASA Technical Reports Server (NTRS)

    Murman, Scott M.; Aftosmis, Michael J.; Rogers, Stuart E.

    2005-01-01

    After video analysis of space shuttle flight STS-107's ascent showed that an object shed from the bipod-ramp region impacted the left wing, a transport analysis was initiated to determine a credible flight path and impact velocity for the piece of debris. This debris transport analysis was performed both during orbit, and after the subsequent re-entry accident. The analysis provided an accurate prediction of the velocity a large piece of foam bipod ramp would have as it impacted the wing leading edge. This prediction was corroborated by video analysis and fully-coupled CFD/six degree of freedom (DOF) simulations. While the prediction of impact velocity was accurate enough to predict critical damage in this case, one of the recommendations of the Columbia Accident Investigation Board (CAIB) for return-to-flight (RTF) was to analyze the complete debris environment experienced by the shuttle stack on ascent. This includes categorizing all possible debris sources, their probable geometric and aerodynamic characteristics, and their potential for damage. This paper is chiefly concerned with predicting the aerodynamic characteristics of a variety of potential debris sources (insulating foam and cork, nose-cone ablator, ice, ...) for the shuttle ascent configuration using CFD methods. These aerodynamic characteristics are used in the debris transport analysis to predict flight path, impact velocity and angle, and provide statistical variation to perform risk analyses where appropriate. The debris aerodynamic characteristics are difficult to determine using traditional methods, such as static or dynamic test data, due to the scaling requirements of simulating a typical debris event. The use of CFD methods has been a critical element for building confidence in the accuracy of the debris transport code by bridging the gap between existing aerodynamic data and the dynamics of full-scale, in-flight events.

  3. Pendant bubble method for an accurate characterization of superhydrophobic surfaces.

    PubMed

    Ling, William Yeong Liang; Ng, Tuck Wah; Neild, Adrian

    2011-12-06

    The commonly used sessile drop method for measuring contact angles and surface tension suffers from errors on superhydrophobic surfaces. This occurs from unavoidable experimental error in determining the vertical location of the liquid-solid-vapor interface due to a camera's finite pixel resolution, thereby necessitating the development and application of subpixel algorithms. We demonstrate here the advantage of a pendant bubble in decreasing the resulting error prior to the application of additional algorithms. For sessile drops to attain an equivalent accuracy, the pixel count would have to be increased by 2 orders of magnitude.

  4. Biogeographical characterization of Saccharomyces cerevisiae wine yeast by molecular methods

    PubMed Central

    Tofalo, Rosanna; Perpetuini, Giorgia; Schirone, Maria; Fasoli, Giuseppe; Aguzzi, Irene; Corsetti, Aldo; Suzzi, Giovanna

    2013-01-01

    Biogeography is the descriptive and explanatory study of spatial patterns and processes involved in the distribution of biodiversity. Without biogeography, it would be difficult to study the diversity of microorganisms because there would be no way to visualize patterns in variation. Saccharomyces cerevisiae, “the wine yeast,” is the most important species involved in alcoholic fermentation, and in vineyard ecosystems, it follows the principle of “everything is everywhere.” Agricultural practices such as farming (organic versus conventional) and floor management systems have selected different populations within this species that are phylogenetically distinct. In fact, recent ecological and geographic studies highlighted that unique strains are associated with particular grape varieties in specific geographical locations. These studies also highlighted that significant diversity and regional character, or ‘terroir,’ have been introduced into the winemaking process via this association. This diversity of wild strains preserves typicity, the high quality, and the unique flavor of wines. Recently, different molecular methods were developed to study population dynamics of S. cerevisiae strains in both vineyards and wineries. In this review, we will provide an update on the current molecular methods used to reveal the geographical distribution of S. cerevisiae wine yeast. PMID:23805132

  5. Characterization of a simplified method of cryopreserving human parathyroid tissue.

    PubMed

    Saxe, A W; Gibson, G W; Kay, S

    1990-12-01

    Cryopreservation of human parathyroid tissue plays an important role in managing difficult parathyroid disease. It also can permit investigators to conduct experiments without dependence on the operating room schedule. Availability of cryopreservation has been limited by the perceived need for expensive, complex equipment. We adapted a simple method of freezing cell suspensions to freezing human parathyroid tissue. Vials containing human parathyroid in culture media, dimethylsulfoxide, and patient serum were placed in a plastic rack in a metal pan containing prechilled (4 degrees C) ethanol and placed in a -70 degrees C freezer. We compared viability (trypan blue dye exclusion by collagenase dispersed cells) of tissue frozen in this manner to that of tissue frozen in a programmable liquid nitrogen freezer at 1 degrees C per minute, a cooling rate recommended for human parathyroid tissue. The viability of 30 patients' samples cooled in liquid nitrogen (average length of storage 5 months) was 74% +/- 15% and that of 64 patients' samples cooled in ethanol (average length of storage 26 months) was 71% +/- 15%. Viability of 19 samples of fresh tissue was 79% +/- 10%. Neither method had a statistically significant correlation between length of storage and viability. Successful cryopreservation with simplified technology may expand the availability of parathyroid tissue to meet both clinical and investigative requirements.

  6. An Extensive Unified Thermo-Electric Module Characterization Method

    PubMed Central

    Attivissimo, Filippo; Guarnieri Calò Carducci, Carlo; Lanzolla, Anna Maria Lucia; Spadavecchia, Maurizio

    2016-01-01

    Thermo-Electric Modules (TEMs) are being increasingly used in power generation as a valid alternative to batteries, providing autonomy to sensor nodes or entire Wireless Sensor Networks, especially for energy harvesting applications. Often, manufacturers provide some essential parameters under determined conditions, like for example, maximum temperature difference between the surfaces of the TEM or for maximum heat absorption, but in many cases, a TEM-based system is operated under the best conditions only for a fraction of the time, thus, when dynamic working conditions occur, the performance estimation of TEMs is crucial to determine their actual efficiency. The focus of this work is on using a novel procedure to estimate the parameters of both the electrical and thermal equivalent model and investigate their relationship with the operating temperature and the temperature gradient. The novelty of the method consists in the use of a simple test configuration to stimulate the modules and simultaneously acquire electrical and thermal data to obtain all parameters in a single test. Two different current profiles are proposed as possible stimuli, which use depends on the available test instrumentation, and relative performance are compared both quantitatively and qualitatively, in terms of standard deviation and estimation uncertainty. Obtained results, besides agreeing with both technical literature and a further estimation method based on module specifications, also provides the designer a detailed description of the module behavior, useful to simulate its performance in different scenarios. PMID:27983575

  7. An Automated Method for Characterizing the Relaxedness of Galaxy Clusters

    SciTech Connect

    George, Matt; /Harvard Coll. Observ. /SLAC

    2005-12-15

    Relaxed galaxy clusters are useful tools for probing cosmological parameters like the gas mass fraction of the universe. Selecting relaxed clusters for this purpose can be a time-consuming and subjective task, so we present methods to automate parts of the process. We fit elliptical isophotes to a diverse sample of Chandra cluster data and summarize other methods for quantifying relaxedness which will be included in future work. Analysis of the results of tests from isophote fitting, combined with numerical simulations of cluster structures and comparison to previous classifications will allow us to formulate criteria for selection of relaxed clusters. We find that they tend to have core radii less than approximately 60 kpc from King model fits, shifts in isophote centroids of less than 25 kpc over a range in semi-major axes of several hundred kpc, and significantly greater surface brightness profile gradients within 30 kpc of their cores than unrelaxed clusters. These criteria will help with future cosmological work as larger amounts of cluster data are taken and need objective classification.

  8. Purification and Characterization of Bovine Serum Albumin Using Chromatographic Method

    PubMed Central

    Balkani, Sanaz; Shamekhi, Sara; Raoufinia, Ramin; Parvan, Reza; Abdolalizadeh, Jalal

    2016-01-01

    Purpose: Albumin is an abundant protein of blood and has many biopharmaceutical applications. The aim of this study was to purify bovine serum albumin (BSA) using produced rabbit anti-BSA antibody. Methods: The polyclonal antibody was produced against the BSA in rabbits. Then, the pure BSA was injected to three white New Zealand rabbits. ELISA test was done to evaluate antibody production. After antibody purification,the purified antibody was attached to CNBr-activated sepharose and finally it was used for purification of albumin from bovine serum. Western blotting analysis was used for functional assessment of immunoaffinity purified BSA. Results: The titer of anti-bovine albumin determined by ELISA was obtained 1: 256000. The SDS-PAGE showed up to 98% purity of isolated BSA and western blotting confirmed the BSA functionality. Purified bovine serum albumin by affinity chromatography showed a single band with molecular weight of 66 KDa. Conclusion: Affinity chromatography using produced rabbit anti-BSA antibody would be an economical and safe method for purification of BSA. PMID:28101473

  9. Study of borehole probing methods to improve the ground characterization

    NASA Astrophysics Data System (ADS)

    Naeimipour, Ali

    Collecting geological information allows for optimizing ground control measures in underground structures. This includes understanding of the joints and discontinuities and rock strength to develop rock mass classifications. An ideal approach to collect such information is through correlating the drilling data from the roofbolters to assess rock strength and void location and properties. The current instrumented roofbolters are capable of providing some information on these properties but not fully developed for accurate ground characterization. To enhance existing systems additional instrumentation and testing was conducted in laboratory and field conditions. However, to define the geology along the boreholes, the use of probing was deemed to be most efficient approach for locating joints and structures in the ground and evaluation of rock strength. Therefore, this research focuses on selection and evaluation of proper borehole probes that can offer a reliable assessment of rock mass structure and rock strength. In particular, attention was paid to borehole televiewer to characterize rock mass structures and joints and development of mechanical rock scratcher for determination of rock strength. Rock bolt boreholes are commonly drilled in the ribs and the roof of underground environments. They are often small (about 1.5 inches) and short (mostly 2-3 meter). Most of them are oriented upward and thus, mostly dry or perhaps wet but not filled with water. No suitable system is available for probing in such conditions to identify the voids/joints and specifically to measure rock strength for evaluation of rock mass and related optimization of ground support design. A preliminary scan of available borehole probes proved that the best options for evaluation of rock structure is through analysis of borehole images, captured by optical televiewers. Laboratory and field trials with showed that these systems can be used to facilitate measurement of the location, frequency and

  10. Precipitation method and characterization of cobalt oxide nanoparticles

    NASA Astrophysics Data System (ADS)

    Prabaharan, D. Durai Manoharadoss; Sadaiyandi, K.; Mahendran, M.; Sagadevan, Suresh

    2017-04-01

    Cobalt oxide (Co3O4) nanoparticles were synthesized using precipitation method. The X-ray diffraction (XRD) pattern was used to determine the structure of Co3O4 nanoparticles. The presence of Co3O4 nanoparticles was confirmed by the FTIR spectrum. The fact about the surface morphology of Co3O4 nanoparticles was revealed by scanning electron microscopic analysis. Transmission electron microscopy was used to measure the particle size of the Co3O4 nanoparticles. The absorption spectrum made it possible to analyze the optical properties of Co3O4 nanoparticles. This work contributes to the study of dielectric properties such as the dielectric loss and the dielectric constant of Co3O4 nanoparticles, at varied frequencies and temperatures. The magnetic properties of the Co3O4 nanoparticles were also investigated.

  11. Characterization of Space Shuttle Ascent Debris Aerodynamics Using CFD Methods

    NASA Technical Reports Server (NTRS)

    Murman, Scott M.; Aftosmis, Michael J.; Rogers, Stuart E.

    2005-01-01

    An automated Computational Fluid Dynamics process for determining the aerodynamic Characteristics of debris shedding from the Space Shuttle Launch Vehicle during ascent is presented. This process uses Cartesian fully-coupled, six-degree-of-freedom simulations of isolated debris pieces in a Monte Carlo fashion to produce models for the drag and crossrange behavior over a range of debris shapes and shedding scenarios. A validation of the Cartesian methods against ballistic range data for insulating foam debris shapes at flight conditions, as well as validation of the resulting models, are both contained. These models are integrated with the existing shuttle debris transport analysis software to provide an accurate and efficient engineering tool for analyzing debris sources and their potential for damage.

  12. PSF and MTF Measurement Methods for Thick CCD Sensor Characterization

    SciTech Connect

    Takacs, P.Z.; Kotov, I.; Frank, J.; O'Connor, P.; Radeka, V.; Lawrence, D.M.

    2010-06-30

    Knowledge of the point spread function (PSF) of the sensors to be used in the Large Synoptic Survey Telescope (LSST) camera is essential for optimal extraction of subtle galaxy shape distortions caused by gravitational weak lensing. We have developed a number of techniques for measuring the PSF of candidate CCD sensors to be used in the LSST camera, each with its own strengths and weaknesses. The two main optical PSF measurement techniques that we use are the direct Virtual Knife Edge (VKE) scan as developed by Karcher, et al. and the indirect interference fringe method after Andersen and Sorensen that measures the modulation transfer function (MTF) directly. The PSF is derived from the MTF by Fourier transform. Other non-optical PSF measurement techniques that we employ include {sup 55}Fe x-ray cluster image size measurements and statistical distribution analysis, and cosmic ray muon track size measurements, but are not addressed here. The VKE technique utilizes a diffraction-limited spot produced by a Point-Projection Microscope (PPM) that is scanned across the sensor with sub-pixel resolution. This technique closely simulates the actual operating condition of the sensor in the telescope with the source spot size having an f/number close to the actual telescope design value. The interference fringe method uses a simple equal-optical-path Michelson-type interferometer with a single-mode fiber source that produces interference fringes with 100% contrast over a wide spatial frequency range sufficient to measure the MTF of the sensor directly. The merits of each measurement technique and results from the various measurement techniques on prototype LSST sensors are presented and compared.

  13. Advanced methods for preparation and characterization of infrared detector materials

    NASA Technical Reports Server (NTRS)

    Broerman, J. G.; Morris, B. J.; Meschter, P. J.

    1983-01-01

    Crystals were prepared by the Bridgman-Stockbarger method with a wide range of crystal growth rates and temperature gradients adequate to prevent constitutional supercooling under diffusion-limited, steady-state, growth conditions. The longitudinal compositional gradients for different growth conditions and alloy compositions were calculated and compared with experimental data to develop a quantitative model of solute redistribution during the crystal growth of the alloys. Measurements were performed to ascertain the effect of growth conditions on radial compositional gradients. The pseudobinary HgTe-CdTe constitutional phase diagram was determined by precision differential-thermal-analysis measurements and used to calculate the segregation coefficient of Cd as a function of x and interface temperature. Experiments were conducted to determine the ternary phase equilibria in selected regions of the Hg-Cd-Te constitutional phase diagram. Electron and hole mobilities as functions of temperature were analyzed to establish charge-carrier scattering probabilities. Computer algorithms specific to Hg(1-x)CdxTe were developed for calculations of the charge-carrier concentration, charge-carrier mobilities, Hall coefficient, and Dermi Fermi energy as functions of x, temperature, ionized donor and acceptor concentrations, and neutral defect concentrations.

  14. Study Methods to Characterize and Implement Thermography Nondestructive Evaluation (NDE)

    NASA Technical Reports Server (NTRS)

    Walker, James L.

    1998-01-01

    The limits and conditions under which an infrared thermographic nondestructive evaluation can be utilized to assess the quality of aerospace hardware is demonstrated in this research effort. The primary focus of this work is on applying thermography to the inspection of advanced composite structures such as would be found in the International Space Station Instrumentation Racks, Space Shuttle Cargo Bay Doors, Bantam RP-1 tank or RSRM Nose Cone. Here, the detection of delamination, disbond, inclusion and porosity type defects are of primary interest. In addition to composites, an extensive research effort has been initiated to determine how well a thermographic evaluation can detect leaks and disbonds in pressurized metallic systems "i.e. the Space Shuttle Main Engine Nozzles". In either case, research into developing practical inspection procedures was conducted and thermographic inspections were performed on a myriad of test samples, subscale demonstration articles and "simulated" flight hardware. All test samples were fabricated as close to their respective structural counterparts as possible except with intentional defects for NDE qualification. As an added benefit of this effort to create simulated defects, methods were devised for defect fabrication that may be useful in future NDE qualification ventures.

  15. Application of thermal methods for characterization of steel welded joints

    NASA Astrophysics Data System (ADS)

    Galietti, U.; Palumbo, D.

    2010-06-01

    Despite the large number of proposals in the field of fatigue prediction of welded joints, a globally accepted and unified theory, which applies easily to any load condition, does not exist. Real life components, indeed, differ in geometry and/or type of load from the structural design for which they are regarded by Standards, so that a lot of precautionary safety factors are used that lead to an underestimation of the actual fatigue life of joints. Infrared thermography has a great potential in this field, both from structural and thermomechanical points of view. It enables a full field stress analysis with a sufficient spatial resolution so that the complexity of the stress state at the weld toe and its time evolution are taken into account, emphasizing anomalies that may predict structural failure. A new methods for evaluation fatigue limit damage is presented in this paper and in particular interesting results derived from analysis of the evolution of thermoelastic signal phase. Variations in the value of signal phase indicate a not elastic behaviour and plastic dissipation in the material.

  16. Characterization of an enriched uranyl fluoride deposit in a valve and pipe intersection using time-of-flight transmission measurements with {sup 252}Cf

    SciTech Connect

    Wyatt, M.S.; Uckan, T.; Mihalczo, J.T.; Valentine, T.E.; Hannon, T.F.

    1998-06-01

    A method was developed and successfully applied to characterize large uranyl fluoride (UO{sub 2}F{sub 2}) deposits at the former Oak Ridge Gaseous Diffusion Plant. These deposits were formed by a wet air in-leakage into the UF{sub 6} process gas lines over a period of years. The resulting UO{sub 2}F{sub 2} is hygroscopic, readily absorbing moisture from the air to form hydrates as UO{sub 2}F{sub 2}-nH{sub 2}O. The ratio of hydrogen to uranium can vary from 0--16, and has significant nuclear criticality safety impacts for large deposits. In order to properly formulate the required course of action, a non-intrusive characterization of the distribution of the fissile material within the pipe, its total mass, and amount of hydration was necessary. The Nuclear Weapons Identification System (NWIS) previously developed at the Oak Ridge Y-12 Plant for identification of uranium weapons components in storage containers was used to successfully characterize these deposits.

  17. Characterization and diagnostic methods for geomagnetic auroral infrasound waves

    NASA Astrophysics Data System (ADS)

    Oldham, Justin J.

    Infrasonic perturbations resulting from auroral activity have been observed since the 1950's. In the last decade advances in infrasonic microphone sensitivity, high latitude sensor coverage, time series analysis methods and computational efficiency have elucidated new types of auroral infrasound. Persistent periods of infrasonic activity associated with geomagnetic sub-storms have been termed geomagnetic auroral infrasound waves [GAIW]. We consider 63 GAIW events recorded by the Fairbanks, AK infrasonic array I53US ranging from 2003 to 2014 and encompassing a complete solar cycle. We make observations of the acoustic features of these events alongside magnetometer, riometer, and all-sky camera data in an effort to quantify the ionospheric conditions suitable for infrasound generation. We find that, on average, the generation mechanism for GAIW is confined to a region centered about ~60 0 longitude east of the anti-Sun-Earth line and at ~770 North latitude. We note furthermore that in all cases considered wherein imaging riometer data are available, that dynamic regions of heightened ionospheric conductivity periodically cross the overhead zenith. Consistent features in concurrent magnetometer conditions are also noted, with irregular oscillations in the horizontal component of the field ubiquitous in all cases. In an effort to produce ionosphere based infrasound free from the clutter and unknowns typical of geophysical observations, an experiment was undertaken at the High Frequency Active Auroral Research Program [HAARP] facility in 2012. Infrasonic signals appearing to originate from a source region overhead were observed briefly on 9 August 2012. The signals were observed during a period when an electrojet current was presumed to have passed overhead and while the facilities radio transmitter was periodically heating the lower ionosphere. Our results suggest dynamic auroral electrojet currents as primary sources of much of the observed infrasound, with

  18. In-house reference material characterization using nuclear methods

    SciTech Connect

    Anderson, D.L.; Cunningham, W.C.

    1994-12-31

    Inclusion of standard reference materials (SRMs) in chemical analysis schemes is an important component of quality control (QC) programs. Effectiveness as QC materials depends on how closely SRM matrices match (in both bulk composition and analyte concentrations) those of the unknowns. For food analysis, wide ranges of matrices and compositions are encountered, and appropriate SRM availability is limited. Moreover, day-to-day use of gram quantities of SRMs during analyses of large numbers of food test samples, such as for the Food and Drug Administration`s (FDA`s) Total Diet Study Program, results in high costs and rapid depletion. To overcome these problems, FDA`s Elemental Research Branch has examined two off-the-shelf foods, soy-based powdered infant formula (SPIF), and cocoa powder, as candidates for in-house (secondary) reference materials. Both materials are relatively homogeneous in particle size and composition and have long shelf lives with no refrigeration. The SPIF is formulated to be a complete infant diet with proper fat content and is fortified with essential vitamins, minerals, and essential elements. At FDA`s Kansas City laboratory, cocoa powder was found to have enough fat to require (desirably) moderate effort for acid digestion and to have cadmium, nickel, and lead concentrations at levels appropriate for graphite furnace atomic absorption spectrometry QC procedures. This material also has suitable concentrations for determination of a number of other elements of interest (e.g., calcium, copper, chromium, iron, potassium, magnesium, manganese, and zinc). Basis weight stabilities, the number of analytes quantitatable by neutron activation methods, and homogeneities for these materials were investigated.

  19. Chemical characterization of Brickellia cavanillesii (Asteraceae) using gas chromatographic methods.

    PubMed

    Eshiet, Etetor R; Zhu, Jinqiu; Anderson, Todd A; Smith, Ernest E

    2014-03-01

    A methanol extract of lyophilized Brickellia cavanillesii was quantitatively analyzed using gas chromatographic (GC) techniques. The chromatographic methods employed were (i) GC-flame ionization detector (GC-FID), (ii) GC-mass spectrometry (GC-MS), and (iii) purge and trap GC-MS (P&T GC-MS). Thirteen compounds were identified with a quality match of 90% and above using GC-MS. The compounds were (1) Cyclohexene, 6-ethenyl-6-methyl-1-(1-methylethyl)-3-(1-methylethylidene)-, (S)-; (2) Bicylo (2.2.1) heptan-2-one, 1, 7, 7-trimethyl-(1S, 4S)-; (3) Phenol, 2-methoxy-4-(1-propenyl)-; (4) Benzene, 1-(1, 5-dimethyl-4-hexenyl)-4-methyl-; (5) Naphthalene, 1, 2, 3, 5, 6, 8a-hexahydro4, 7-dimethyl-1-1-(1-methylethyl)-, (1S-cis)-; (6) Phenol, 2-methoxy-; (7) Benzaldehyde, 3-hydroxy-4-methoxy-; (8) 11, 13-Eicosadienoic acid, methyl ester; (9) 2-Furancarboxaldehyde, 5-methyl-; (10) Maltol; (11) Phenol; (12) Hydroquinone; (13) 1H-Indene, 1-ethylideneoctahydro-7a-methyl-, (1E, 3a.alpha, 7a.beta.). Other compounds (14) 3-methyl butanal; (15) (D)-Limonene; (16) 1-methyl-4-(1-methyl ethyl) benzene; (17) Butanoic acid methyl ester; (18) 2-methyl propanal; (19) 2-butanone; (20) 2-pentanone; and (21) 2-methyl butane were also identified when P&T GC-MS was performed. Of the 21 compounds identified, 12 were validated using chemical standards. The identified compounds were found to be terpenes, derivatives of terpenes, esters, ketones, aldehydes, and phenol-derived aromatic compounds; these are the primary constituents of the essential oils of many plants and flowers.

  20. Chemical characterization of Brickellia cavanillesii (Asteraceae) using gas chromatographic methods

    PubMed Central

    Eshiet, Etetor R; Zhu, Jinqiu; Anderson, Todd A; Smith, Ernest E

    2014-01-01

    A methanol extract of lyophilized Brickellia cavanillesii was quantitatively analyzed using gas chromatographic (GC) techniques. The chromatographic methods employed were (i) GC-flame ionization detector (GC-FID), (ii) GC-mass spectrometry (GC-MS), and (iii) purge and trap GC-MS (P&T GC-MS). Thirteen compounds were identified with a quality match of 90% and above using GC-MS. The compounds were (1) Cyclohexene, 6-ethenyl-6-methyl-1-(1-methylethyl)-3-(1-methylethylidene)-, (S)-; (2) Bicylo (2.2.1) heptan-2-one, 1, 7, 7-trimethyl-(1S, 4S)-; (3) Phenol, 2-methoxy-4-(1-propenyl)-; (4) Benzene, 1-(1, 5-dimethyl-4-hexenyl)-4-methyl-; (5) Naphthalene, 1, 2, 3, 5, 6, 8a-hexahydro4, 7-dimethyl-1-1-(1-methylethyl)-, (1S-cis)-; (6) Phenol, 2-methoxy-; (7) Benzaldehyde, 3-hydroxy-4-methoxy-; (8) 11, 13-Eicosadienoic acid, methyl ester; (9) 2-Furancarboxaldehyde, 5-methyl-; (10) Maltol; (11) Phenol; (12) Hydroquinone; (13) 1H-Indene, 1-ethylideneoctahydro-7a-methyl-, (1E, 3a.alpha, 7a.beta.). Other compounds (14) 3-methyl butanal; (15) (D)-Limonene; (16) 1-methyl-4-(1-methyl ethyl) benzene; (17) Butanoic acid methyl ester; (18) 2-methyl propanal; (19) 2-butanone; (20) 2-pentanone; and (21) 2-methyl butane were also identified when P&T GC-MS was performed. Of the 21 compounds identified, 12 were validated using chemical standards. The identified compounds were found to be terpenes, derivatives of terpenes, esters, ketones, aldehydes, and phenol-derived aromatic compounds; these are the primary constituents of the essential oils of many plants and flowers. PMID:24804069

  1. Assessment of Proper Bonding Methods and Mechanical Characterization FPGA CQFPs

    NASA Technical Reports Server (NTRS)

    Davis, Milton C.

    2008-01-01

    This presentation discusses fractured leads on field-programmable gate array (FPGA) during flight vibration. Actions taken to determine root cause and resolution of the failure include finite element analysis (FEA) and vibration testing and scanning electron microscopy (with X-ray microanalysis) and energy dispersive spectrometry (SEM/EDS) failure assessment. Bonding methods for surface mount parts is assessed, including critical analysis and assessment of random fatigue damage. Regarding ceramic quad flat pack (CQFP) lead fracture, after disassembling the attitude control electronics (ACE) configuration, photographs showed six leads cracked on FPGA RTSX72SU-1 CQ208B package located on the RWIC card. An identical package (FPGA RTSX32SU-1 CQ208B) mounted on the RWIC did not results in cracked pins due to vibration. FPGA lead failure theories include workmanship issues in the lead-forming, material defect in the leads of the FPGA packages, and the insecure mounting of the board in the card guides, among other theories. Studies were conducted using simple calculations to determine the response and fatigue life of the package. Shorter packages exhibited more response when loaded by out-of-plane displacement of PCB while taller packages exhibit more response when loaded by in-plane acceleration of PCB. Additionally, under-fill did not contribute to reducing stress in leads due to out-of-plane PCB loading or from component twisting, as much as corner bonding. The combination of corner bond and under-fill is best to address mechanical and thermal S/C environment. Test results of bonded parts showed reduced (dampened) amplitude and slightly shifted peaks at the un-bonded natural frequency and an additional response at the bonded frequency. Stress due to PCBB out-of-plane loading was decreased on in the corners when only a corner bond was used. Future work may address CQFP fatigue assessment, including the investigation of discrepancy in predicted fatigue damage, as well as

  2. Development of method to characterize emissions from spray polyurethane foam insulation

    EPA Science Inventory

    This presentation updates symposium participants re EPA progress towards development of SPF insulation emissions characterization methods. The presentation highlights evaluation of experiments investigating emissions after application of SPF to substrates in micro chambers and i...

  3. The Development of Testing Methods for Characterizing Emissions and Sources of Exposures from Polyurethane Products

    EPA Science Inventory

    The relationship between onsite manufacture of spray polyurethane foam insulation (SPFI) and potential exposures is not well understood. Currently, no comprehensive standard test methods exist for characterizing and quantifying product emissions. Exposures to diisocyanate compoun...

  4. Efficient Characterization of Parametric Uncertainty of Complex (Bio)chemical Networks.

    PubMed

    Schillings, Claudia; Sunnåker, Mikael; Stelling, Jörg; Schwab, Christoph

    2015-08-01

    Parametric uncertainty is a particularly challenging and relevant aspect of systems analysis in domains such as systems biology where, both for inference and for assessing prediction uncertainties, it is essential to characterize the system behavior globally in the parameter space. However, current methods based on local approximations or on Monte-Carlo sampling cope only insufficiently with high-dimensional parameter spaces associated with complex network models. Here, we propose an alternative deterministic methodology that relies on sparse polynomial approximations. We propose a deterministic computational interpolation scheme which identifies most significant expansion coefficients adaptively. We present its performance in kinetic model equations from computational systems biology with several hundred parameters and state variables, leading to numerical approximations of the parametric solution on the entire parameter space. The scheme is based on adaptive Smolyak interpolation of the parametric solution at judiciously and adaptively chosen points in parameter space. As Monte-Carlo sampling, it is "non-intrusive" and well-suited for massively parallel implementation, but affords higher convergence rates. This opens up new avenues for large-scale dynamic network analysis by enabling scaling for many applications, including parameter estimation, uncertainty quantification, and systems design.

  5. Optical characterization of high speed microscanners based on static slit profiling method

    NASA Astrophysics Data System (ADS)

    Alaa Elhady, A.; Sabry, Yasser M.; Khalil, Diaa

    2017-01-01

    Optical characterization of high-speed microscanners is a challenging task that usually requires special high speed, extremely expensive camera systems. This paper presents a novel simple method to characterize the scanned beam spot profile and size in high-speed optical scanners under operation. It allows measuring the beam profile and the spot sizes at different scanning angles. The method is analyzed theoretically and applied experimentally on the characterization of a Micro Electro Mechanical MEMS scanner operating at 2.6 kHz. The variation of the spot size versus the scanning angle, up to ±15°, is extracted and the dynamic bending curvature effect of the micromirror is predicted.

  6. A Method for Eliminating Beam Steering Error for the Modulated Absorption-Emission Thermometry Technique

    DTIC Science & Technology

    2014-01-01

    currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE (DD-MM-YYYY) Jan 2014 2. REPORT TYPE Technical...Paper 3. DATES COVERED (From - To) Jan 2014- June 2014 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER In-House A Method for Eliminating Beam...14194 14. ABSTRACT Modulated absorption-emission thermometry (MAET) is a non-intrusive, radiometric technique for measuring line-of-sight average

  7. A Method for Eliminating Beam Steering Error for the Modulated Absorption-Emission Thermometry Technique

    DTIC Science & Technology

    2015-01-01

    currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE (DD-MM-YYYY) December 2014 2. REPORT TYPE...Briefing Charts 3. DATES COVERED (From - To) December 2014- January 2015 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER N/A A Method for Eliminating...Jan 2015. PA#14562. 14. ABSTRACT Modulated absorption-emission thermometry (MAET) is a non-intrusive, radiometric technique for measuring line-of

  8. Sensitive method to identify and characterize proteinases in situ after SDS-PAGE.

    PubMed

    Williams, J; McGrath, W J; Mangel, W F

    2000-11-01

    Cells and body fluids contain numerous, different proteinases; to identify and characterize them are both important and difficult tasks. Especially difficult to identify and characterize are highly specific proteinases. Here, we present an extremely sensitive and quantitative method to characterize proteinases fractionated by SDS-PAGE that cleave specific rhodamine-based fluorogenic substrates. To test the sensitivity of the technique, we used trypsin as our model system. Filter paper impregnated with rhodamine-based fluorogenic substrates was placed on a gel, and bands of fluorescence originating from specific proteinases were visualized in real time. The method is very sensitive; picogram amounts of trypsin can be detected. The method should be very general, in that even proteinases whose substrates require amino acids C-terminal to the cleavage site may be identified and characterized. The results allow one to obtain not only information on the substrate specificity of a specific enzyme but also information about its molecular weight.

  9. A method to characterize the roughness of 2-D line features: recrystallization boundaries.

    PubMed

    Sun, J; Zhang, Y B; Dahl, A B; Conradsen, K; Juul Jensen, D

    2017-03-01

    A method is presented, which allows quantification of the roughness of nonplanar boundaries of objects for which the neutral plane is not known. The method provides quantitative descriptions of both the local and global characteristics. How the method can be used to estimate the sizes of rough features and local curvatures is also presented. The potential of the method is illustrated by quantification of the roughness of two recrystallization boundaries in a pure Al specimen characterized by scanning electron microscopy.

  10. Characterization of molecularly imprinted polymers using a new polar solvent titration method.

    PubMed

    Song, Di; Zhang, Yagang; Geer, Michael F; Shimizu, Ken D

    2014-07-01

    A new method of characterizing molecularly imprinted polymers (MIPs) was developed and tested, which provides a more accurate means of identifying and measuring the molecular imprinting effect. In the new polar solvent titration method, a series of imprinted and non-imprinted polymers were prepared in solutions containing increasing concentrations of a polar solvent. The polar solvent additives systematically disrupted the templation and monomer aggregation processes in the prepolymerization solutions, and the extent of disruption was captured by the polymerization process. The changes in binding capacity within each series of polymers were measured, providing a quantitative assessment of the templation and monomer aggregation processes in the imprinted and non-imprinted polymers. The new method was tested using three different diphenyl phosphate imprinted polymers made using three different urea functional monomers. Each monomer had varying efficiencies of templation and monomer aggregation. The new MIP characterization method was found to have several advantages. To independently verify the new characterization method, the MIPs were also characterized using traditional binding isotherm analyses. The two methods appeared to give consistent conclusions. First, the polar solvent titration method is less susceptible to false positives in identifying the imprinting effect. Second, the method is able to differentiate and quantify changes in binding capacity, as measured at a fixed guest and polymer concentration, arising from templation or monomer aggregation processes in the prepolymerization solution. Third, the method was also easy to carry out, taking advantage of the ease of preparing MIPs.

  11. HPLC method to characterize cyanogen bromide collagen fractions containing pyridinoline groups.

    PubMed

    Bruno, R; Mazza, R; Calafiori, A R; Covello, C; Falbo, L; Martino, G; Marotta, M

    1997-01-01

    The HPLC method here described allows to separate CNBr collagen peptides within 2.5 h by reversed phase and gradient elution. The method is useful to determine both peptide bond and pyridinoline groups by absorbance spectophotometry. The fractions can be recovered and then submitted to other characterization techniques.

  12. Acousto-Optic Tunable Filter Hyperspectral Microscope Imaging Method for Characterizing Spectra from Foodborne Pathogens.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hyperspectral microscope imaging (HMI) method, which provides both spatial and spectral characteristics of samples, can be effective for foodborne pathogen detection. The acousto-optic tunable filter (AOTF)-based HMI method can be used to characterize spectral properties of biofilms formed by Salmon...

  13. A new method for anisotropic materials characterization based on phased-array ultrasonic transducers technology

    SciTech Connect

    Frenet, D.; Calmon, P.; Paradis, L.

    1999-12-02

    A method for materials characterization based on the utilization of a ultrasonic array transducer of conical shape has been developed at the CEA. The specific design of this transducer allows the generation and the detection of leaky surface acoustic waves (LSAW) in an efficient way. Additionally, anisotropic materials can be investigated in several azimuthal directions without any mechanical movement. The characterization process relies on the velocity measurement of the LSAW. Experimental results on both isotropic an anisotropic material are reported.

  14. Characterization of Large Grain Nb Ingot Microstructure Using EBSP Mapping and Laue Camera Methods

    NASA Astrophysics Data System (ADS)

    Kang, Di; Baars, Derek C.; Bieler, Thomas R.; Compton, Chris C.

    2011-03-01

    Large grain/single crystal Nb is currently being examined for fabricating superconducting radiofrequency (SRF) cavities as an alternative to using rolled sheet. Three ingot slices from different suppliers have been characterized and are compared. It is desirable to know the grain orientations of an ingot slice before fabrication. Characterization of an ingot slice has been done using electron backscattered pattern (EBSP) orientation imaging microscopy (OIM), which requires cutting out pieces from the slice, a destructive technique. Use of a Laue camera allows nondestructive characterization of grain orientations. The OIM method was used to examine ingot slices from CBMM and Ningxia, while the Laue method was used to examine a Heraeus ingot slice. The three ingot slices are compared in terms of their crystal orientations and grain boundary misorientations, indicating no obvious commonalities. The Laue method has practical advantages over OIM for evaluating ingot slices during the manufacturing process.

  15. Characterization of Large Grain Nb Ingot Microstructure Using EBSP Mapping and Laue Camera Methods

    SciTech Connect

    Kang Di; Baars, Derek C.; Bieler, Thomas R.; Compton, Chris C.

    2011-03-31

    Large grain/single crystal Nb is currently being examined for fabricating superconducting radiofrequency (SRF) cavities as an alternative to using rolled sheet. Three ingot slices from different suppliers have been characterized and are compared. It is desirable to know the grain orientations of an ingot slice before fabrication. Characterization of an ingot slice has been done using electron backscattered pattern (EBSP) orientation imaging microscopy (OIM), which requires cutting out pieces from the slice, a destructive technique. Use of a Laue camera allows nondestructive characterization of grain orientations. The OIM method was used to examine ingot slices from CBMM and Ningxia, while the Laue method was used to examine a Heraeus ingot slice. The three ingot slices are compared in terms of their crystal orientations and grain boundary misorientations, indicating no obvious commonalities. The Laue method has practical advantages over OIM for evaluating ingot slices during the manufacturing process.

  16. An Innovative Method for Dynamic Characterization of Fan FilterUnit Operation.

    SciTech Connect

    Xu, Tengfang

    2006-12-21

    Fan filter units (FFU) are widely used to deliver re-circulated air while providing filtration control of particle concentration in controlled environments such as cleanrooms, minienvironments, and operating rooms in hospitals. The objective of this paper is to document an innovative method for characterizing operation and control of an individual fan filter unit within its operable conditions. Built upon the draft laboratory method previously published [1] , this paper presents an updated method including a testing procedure to characterize dynamic operation of fan filter units, i.e., steady-state operation conditions determined by varied control schemes, airflow rates, and pressure differential across the units. The parameters for dynamic characterization include total electric power demand, total pressure efficiency, airflow rate, pressure differential across fan filter units, and airflow uniformity.

  17. Using pre-screening methods for an effective and reliable site characterization at megasites.

    PubMed

    Algreen, Mette; Kalisz, Mariusz; Stalder, Marcel; Martac, Eugeniu; Krupanek, Janusz; Trapp, Stefan; Bartke, Stephan

    2015-10-01

    This paper illustrates the usefulness of pre-screening methods for an effective characterization of polluted sites. We applied a sequence of site characterization methods to a former Soviet military airbase with likely fuel and benzene, toluene, ethylbenzene, and xylene (BTEX) contamination in shallow groundwater and subsoil. The methods were (i) phytoscreening with tree cores; (ii) soil gas measurements for CH4, O2, and photoionization detector (PID); (iii) direct-push with membrane interface probe (MIP) and laser-induced fluorescence (LIF) sensors; (iv) direct-push sampling; and (v) sampling from soil and from groundwater monitoring wells. Phytoscreening and soil gas measurements are rapid and inexpensive pre-screening methods. Both indicated subsurface pollution and hot spots successfully. The direct-push sensors yielded 3D information about the extension and the volume of the subsurface plume. This study also expanded the applicability of tree coring to BTEX compounds and tested the use of high-resolution direct-push sensors for light hydrocarbons. Comparison of screening results to results from conventional soil and groundwater sampling yielded in most cases high rank correlation and confirmed the findings. The large-scale application of non- or low-invasive pre-screening can be of help in directing and focusing the subsequent, more expensive investigation methods. The rapid pre-screening methods also yielded useful information about potential remediation methods. Overall, we see several benefits of a stepwise screening and site characterization scheme, which we propose in conclusion.

  18. Small-angle X-ray scattering method to characterize molecular interactions: Proof of concept.

    PubMed

    Allec, Nicholas; Choi, Mina; Yesupriya, Nikhil; Szychowski, Brian; White, Michael R; Kann, Maricel G; Garcin, Elsa D; Daniel, Marie-Christine; Badano, Aldo

    2015-07-10

    Characterizing biomolecular interactions is crucial to the understanding of biological processes. Existing characterization methods have low spatial resolution, poor specificity, and some lack the capability for deep tissue imaging. We describe a novel technique that relies on small-angle X-ray scattering signatures from high-contrast molecular probes that correlate with the presence of biomolecular interactions. We describe a proof-of-concept study that uses a model system consisting of mixtures of monomer solutions of gold nanoparticles (GNPs) as the non-interacting species and solutions of GNP dimers linked with an organic molecule (dimethyl suberimidate) as the interacting species. We report estimates of the interaction fraction obtained with the proposed small-angle X-ray scattering characterization method exhibiting strong correlation with the known relative concentration of interacting and non-interacting species.

  19. Contactless Method for Electrical Characterization of Silicon-on-Insulator Materials

    NASA Astrophysics Data System (ADS)

    Okumura, Tsugunori; Eguchi, Kazuyoshi; En, Aimin; Suhara, Michihiko

    2001-09-01

    The Kelvin-probe method, in combination with surface photovoltage (SPV) measurements, is applied to the nondestructive electrical characterization of silicon-on-insulator (SOI) materials. It is shown that a simple sandwich-type electrode configuration can be used for the contactless characterization of the SOI layer, when the capacitance between the vibrating electrode and the SOI surface is much smaller than the buried-oxide (BOX) and depletion-layer series capacitances. The light-intensity dependence of the SPV gives data equivalent to common cuurent-voltage (I-V) characteristics of diodes. Thus, we call the proposed method the contactless I-V method. Lastly, we demonstrate that UV illumination is effective for applying the contactless I-V method to ultrathin SOI layers such as fully depleted SOI material.

  20. A surface intrinsic feature based method (SIFBM) for the characterization of optical microstructure

    NASA Astrophysics Data System (ADS)

    Cheung, C. F.; Kong, L. B.; Lee, W. B.; To, S.

    2008-12-01

    Optical microstructures are small scale topologies which are generally classified as grooves, pyramids, microlens arrays, lenticulations, echells, etc. They are widely used in advanced optics applications. Currently, there is lack of methods for the characterization of surface quality for optical microstructures with sub-micromenter form accuracy and surface finish in the nanometer range. This paper presents a Surface Intrinsic Feature Based Method (SIFBM) which makes use of surface intrinsic properties such as curvatures, normal vectors, torsion, intrinsic frames, etc. They are mapped as special images and image processing techniques are then employed to conduct image registration or correspondences searching by some algorithms such as correlation functions. The surface matching is optimized by corresponding vectors deviations. In the present study, a prototype surface characterization system has been built based on the SIFBM. Primary experimental work has been conducted to validate the proposed method. The results demonstrate that the SIFBM has potential advantages over existing methods.

  1. Characterization and classification of pseudo-stationary phases in micellar electrokinetic chromatography using chemometric methods.

    PubMed

    Fu, Cexiong; Khaledi, Morteza G

    2014-03-04

    Two types of chemometric methods, principal component analysis (PCA) and cluster analysis, are employed to characterize and classify a total of 70 pseudostationary phases (54 distinct systems and 16 decoy systems) in micellar electrokinetic chromatography (MEKC). PCA excels at removing redundant information for micellar phase characterization and retaining principal determinants for phase classification. While PCA is useful in the characterization of micelle selectivities, it is ineffective in defining the grouping of micellar phases. Hierarchical clustering yields a complete dendrogram of cluster structures but provides only limited cluster characterizations. The combination of these two chemometric methods leads to a comprehensive interpretation of the micellar phase classification. Moreover, the k-means analysis can further discern subtle differences among those closely located micellar phases. All three chemometric methods result in similar classifications with respect to the similarities and differences of the 70 micelle systems investigated. These systems are categorized into 3 major clusters: fluoro-surfactants represent cluster I, identified as strong hydrogen bond donors and dipolar but weak hydrogen bond acceptors. Cluster II includes sulfonated acrylamide/acrylate copolymers and surfactants with trimethylammonium head groups, characterized by strong hydrophobicity (v) and weak hydrogen bond acidity (b). The last cluster consists of two subclusters: clusters III and IV. Cluster III includes siloxane-based polymeric micelles, exhibiting weak hydrophobicity and medium hydrogen bond acidity and basicity (a), and the cluster IV micellar systems are characterized by their strong hydrophobicity and medium hydrogen bond acidity and basicity but rather weak dipolarity. Cluster III differs from cluster IV by its slightly weaker hydrophobicity and hydrogen bond donating capability. The classification by chemometric methods is in good agreement with the

  2. A method of characterizing network topology based on the breadth-first search tree

    NASA Astrophysics Data System (ADS)

    Zhou, Bin; He, Zhe; Wang, Nianxin; Wang, Bing-Hong

    2016-05-01

    A method based on the breadth-first search tree is proposed in this paper to characterize the hierarchical structure of network. In this method, a similarity coefficient is defined to quantitatively distinguish networks, and quantitatively measure the topology stability of the network generated by a model. The applications of the method are discussed in ER random network, WS small-world network and BA scale-free network. The method will be helpful for deeply describing network topology and provide a starting point for researching the topology similarity and isomorphism of networks.

  3. Intrusive and Non-Intrusive Instruction in Dynamic Skill Training.

    DTIC Science & Technology

    1981-10-01

    Bachrach Environmental Stress Program Center I Dr. Lloyd Hitchcock Naval Medical Research Institute Human Factors Engineering Bethesda, MD 20014 Division...22217 Washington, DC 20350 5 Personnel & Training Research Programs 1 Dr. Alfred F. Smode (Code 458) Training Analysis & Evaluation Group Office of... Alfred R. Fregly Arlington, VA 22217 AFOSR/NL, Bldg. 410] Bolling AFB 1 DR. A.L. SLAFKOSKY Washington, DC 20332 SCIENTIFIC ADVISOR (CODE RD-i) HO

  4. Harmonic Approaches to Non-Intrusive Load Diagnostics

    DTIC Science & Technology

    2008-06-01

    physical characteristics, such as induction motor rotor slots, coupled with using clean current spectral regions support automated diagnostic system...3.4 Developing NILM-based Diagnostics for Induction Machines ....................................... 41 3.4.1 Identify key motor parameters...24 Figure 2-10: Typical Induction Motor Start-up Current Measurement [22]................................ 24 Figure 2-11: Block diagram of

  5. Improving Shipboard Applications of Non-Intrusive Load Monitoring

    DTIC Science & Technology

    2008-06-01

    hereafter created , Author m~~~;’;’~~;~i M~~h~~;~~1 E~~;~;~;i~~~~d System Design and Management Program Certified by ~ ~ay9:2.008 Robert W. Cox Assistant... Create the figure, the indications and the system diagram...8217); GUI_LAYOUT.ResetButton = uicontrol (GUI_LAYOUT. MainFigure , ’Style’ , ’pushbutton’, ... ’String’, ’Reset’, ... ’Position’, [660 480 90 30], ... ’Callback

  6. Shipboard Fluid System Diagnostics Using Non-Intrusive Load Monitoring

    DTIC Science & Technology

    2007-06-01

    funding Officers and Crew of the USCGC Escanaba Officers and Crew of the USCGC Seneca Professor Robert Cox for his enthusiasm, assistance, and...45 Figure 3-18: Seneca RO Unit Membrane Seal Failure Detection...Table 2-2: RC7000 Plus RO Unit Component Details ................................................................ 19 Table 2-3: Seneca NILM Setup

  7. Non-intrusive parameter identification procedure user's guide

    NASA Technical Reports Server (NTRS)

    Hanson, G. D.; Jewell, W. F.

    1983-01-01

    Written in standard FORTRAN, NAS is capable of identifying linear as well as nonlinear relations between input and output parameters; the only restriction is that the input/output relation be linear with respect to the unknown coefficients of the estimation equations. The output of the identification algorithm can be specified to be in either the time domain (i.e., the estimation equation coefficients) or in the frequency domain (i.e., a frequency response of the estimation equation). The frame length ("window") over which the identification procedure is to take place can be specified to be any portion of the input time history, thereby allowing the freedom to start and stop the identification procedure within a time history. There also is an option which allows a sliding window, which gives a moving average over the time history. The NAS software also includes the ability to identify several assumed solutions simultaneously for the same or different input data.

  8. Advanced Non-Intrusive Instrumentation for Propulsion Engines

    DTIC Science & Technology

    1998-05-01

    skirt extension liner materials, the original asbestos phenolic, and the LD quartz phenolic. Both nozzle liners rely on considerable fuel-film cool...boundary layer with comparably high wall shear stress. Thus, the velocity profiles visualize a la- minar separation in combination with turbulent...whereas in the la- minar region and in the fully developed turbulent boundary layer the periodic wakes cause no effects at all. Figure 12 visualizes

  9. Non-intrusive long-term monitoring approaches

    SciTech Connect

    Smathers, D.; Mangan, D.

    1998-08-01

    In order to promote internatinal confidence that the US and Russia are disarming per their commitments under Article 6 of the Non-Proliferation Treaty, an international verification regime may be applied to US and Russian excess fissile materials. Initially, it is envisioned that this verification regime would be applied at storage facilities; however, it should be anticipated that the verificatino regime would continue throughout any material disposition activities, should such activities be pursued. once the materials are accepted into the verification regime, it is assumed that long term monitoring will be used to maintain continuity of knowledge. The requirements for long term storage monitoring include unattended operation for extended periods of time, minimal intrusiveness on the host nation`s safety and security activities, data collection incorporating data authentication, and monitoring redundancy to allow resolution of anomalies and to continue coverage in the event of equipment failures. Additional requirements include effective data review and analysis processes, operation during storage facility loading, procedure for removal of inventory items for safety-related surveillance, and low cost, reliable equipment. A monitoring system might include both continuous monitoring of storagecontainers and continuous area monitoring. These would be complemented with periodic on-site inspections. A fissile material storage facility is not a static operation. The initial studies have shown there are a number of volid reasions why a host nation may need them to remove material from the storage facility. A practical monitoring system must be able to accommodate necessary material movements.

  10. COLLECTION OF AMBIENT PARTICULATE MATTER BY POROUS VEGETATION BARRIERS: SAMPLING AND CHARACTERIZATION METHODS

    EPA Science Inventory

    This manuscript describes work done by A. Reff as part of a collaboration begun 3 years ago at Rutgers University with A. Tiwary who was then at the University of Nottingham. The work describes sampling and characterization methods for investigating the effects of vegetative bar...

  11. Collision-induced fragmentation accurate mass spectrometric analysis methods to rapidly characterize phytochemicals in plant extracts

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The rapid advances in analytical chromatography equipment have made the reliable and reproducible measurement of a wide range of plant chemical components possible. Full chemical characterization of a given plant material is possible with the new mass spectrometers currently available. New methods a...

  12. Characterization methods for radiation crosslinked poly(vinyl methyl ether) hydrogels

    NASA Astrophysics Data System (ADS)

    Schmidt, Thomas; Querner, Claudia; Arndt, Karl-Friedrich

    2003-08-01

    The paper reviews recent results of radiation crosslinking of poly(vinyl methyl ether) (PVME). It will give an overview of possible characterization methods for both, soluble and crosslinked PVME. The irradiation of aqueous low concentrated PVME solutions with γ-rays of low doses results in structural changes of PVME molecules. We are able to monitor changes in the chemical structure by spectroscopic methods (IR, NMR) as well as the changes of molecular parameters (e.g. molecular weight, molecular weight distribution, branches) by classical methods for polymer characterization (size exclusion chromatography with diverse detector systems, SLS, viscosimetry). The characterization of the network parameters (crosslinking density νc, molecular weight of the network chains Mc) of PVME bulkgels crosslinked by irradiation at high dose values by classical methods (swelling and compression measurements) provides incorrect results because of the high porosity of the gels. PVME microgel particles can be prepared by irradiation of a phase separated diluted aqueous PVME solution above their lower critical solution temperature. These microgels with decreased dimensions were characterized by SLS, DLS and field emission scanning electron microscopy.

  13. Method of characterizing residual stress in ferromagnetic materials using a pulse histogram of acoustic emission signals

    NASA Technical Reports Server (NTRS)

    Namkung, Min (Inventor); Yost, William T. (Inventor); Kushnick, Peter W. (Inventor); Grainger, John L. (Inventor)

    1992-01-01

    The invention is a method and apparatus for characterizing residual uniaxial stress in a ferromagnetic test member by distinguishing between residual stresses resulting from positive (tension) forces and negative (compression) forces by using the distinct and known magnetoacoustic (MAC) and a magnetoacoustic emission (MAE) measurement circuit means. A switch permits the selective operation of the respective circuit means.

  14. TEST METHODS TO CHARACTERIZE PARTICULATE MATTER EMISSIONS AND DEPOSITION RATES IN A RESEARCH HOUSE

    EPA Science Inventory

    The paper discusses test methods to characterize particulate matter (PM) emissions and deposition rates in a research house. In a room in the research house, specially configured for PM source testing, a high-efficiency particulate air (HEPA)-filtered air supply system, used for...

  15. Reasoning Maps: A Generally Applicable Method for Characterizing Hypothesis-Testing Behaviour. Research Report

    ERIC Educational Resources Information Center

    White, Brian

    2004-01-01

    This paper presents a generally applicable method for characterizing subjects' hypothesis-testing behaviour based on a synthesis that extends on previous work. Beginning with a transcript of subjects' speech and videotape of their actions, a Reasoning Map is created that depicts the flow of their hypotheses, tests, predictions, results, and…

  16. Characterizing a novel and sensitive method to measure dsRNA in soil.

    PubMed

    Fischer, Joshua R; Zapata, Fatima; Dubelman, Samuel; Mueller, Geoffrey M; Jensen, Peter D; Levine, Steven L

    2016-10-01

    Performing environmental assessments for double-stranded RNA-based agricultural products require the development of sensitive and selective methods to measure biodegradation rates of dsRNAs. We developed and characterized a novel analytical procedure that uses a molecular hybridization assay (QuantiGene(®)) to accurately measure dsRNA extracted from diverse soils. In this report, we utilize this method to demonstrate that two dsRNAs with distinct size, structure, and sequence degrade rapidly in soil with indistinguishable kinetics.

  17. Guidance for characterizing explosives contaminated soils: Sampling and selecting on-site analytical methods

    SciTech Connect

    Crockett, A.B.; Craig, H.D.; Jenkins, T.F.; Sisk, W.E.

    1996-09-01

    A large number of defense-related sites are contaminated with elevated levels of secondary explosives. Levels of contamination range from barely detectable to levels above 10% that need special handling due to the detonation potential. Characterization of explosives-contaminated sites is particularly difficult due to the very heterogeneous distribution of contamination in the environment and within samples. To improve site characterization, several options exist including collecting more samples, providing on-site analytical data to help direct the investigation, compositing samples, improving homogenization of samples, and extracting larger samples. On-site analytical methods are essential to more economical and improved characterization. On-site methods might suffer in terms of precision and accuracy, but this is more than offset by the increased number of samples that can be run. While verification using a standard analytical procedure should be part of any quality assurance program, reducing the number of samples analyzed by the more expensive methods can result in significantly reduced costs. Often 70 to 90% of the soil samples analyzed during an explosives site investigation do not contain detectable levels of contamination. Two basic types of on-site analytical methods are in wide use for explosives in soil, calorimetric and immunoassay. Calorimetric methods generally detect broad classes of compounds such as nitroaromatics or nitramines, while immunoassay methods are more compound specific. Since TNT or RDX is usually present in explosive-contaminated soils, the use of procedures designed to detect only these or similar compounds can be very effective.

  18. Motor degradation prediction methods

    SciTech Connect

    Arnold, J.R.; Kelly, J.F.; Delzingaro, M.J.

    1996-12-01

    Motor Operated Valve (MOV) squirrel cage AC motor rotors are susceptible to degradation under certain conditions. Premature failure can result due to high humidity/temperature environments, high running load conditions, extended periods at locked rotor conditions (i.e. > 15 seconds) or exceeding the motor`s duty cycle by frequent starts or multiple valve stroking. Exposure to high heat and moisture due to packing leaks, pressure seal ring leakage or other causes can significantly accelerate the degradation. ComEd and Liberty Technologies have worked together to provide and validate a non-intrusive method using motor power diagnostics to evaluate MOV rotor condition and predict failure. These techniques have provided a quick, low radiation dose method to evaluate inaccessible motors, identify degradation and allow scheduled replacement of motors prior to catastrophic failures.

  19. Development of a method to characterize high-protein dairy powders using an ultrasonic flaw detector.

    PubMed

    Hauser, M; Amamcharla, J K

    2016-02-01

    Dissolution behavior of high-protein dairy powders plays a critical role for achieving functional and nutritional characteristics of a finished food product. Current methods for evaluating powder dissolution properties are time consuming, difficult to reproduce, and subjective. Ultrasound spectroscopy is a rapid and precise method, but requires expensive equipment and skilled technicians to carry out the tests. In the present study, an ultrasonic flaw detector (UFD) was used as an economical alternative to characterize the powder dissolution properties. The objective of study was to develop a method to characterize the dissolution behavior of milk protein concentrate (MPC) using a UFD. The experimental setup included a UFD connected to a 1-MHz immersion transducer that was kept a constant distance from a reflector plate. To validate the method, 2 batches of MPC80 from a commercial manufacturer were procured and stored at 25 and 40°C for 4 wk. Focus beam reflectance measurement and solubility index were used as reference methods. Relative ultrasound velocity and ultrasound attenuation were acquired during the dissolution of MPC samples. To characterize the MPC dissolution, 4 parameters including standard deviation of relative velocity, area under the attenuation curve, and peak attenuation were extracted from ultrasound data. As the storage temperature and time increased, the area under the attenuation curve and peak height decreased, indicating a loss of solubility. The proposed UFD-based method was able to capture the changes in dissolution of MPC during storage at 25 and 40°C. It was observed that a high-quality MPC had a low standard deviation and a larger area under the attenuation curve. As the MPC aged at 40°C, the particle dispersion rate decreased and, consequently, an increase in standard deviation and reduction in area were observed. Overall, the UFD can be a low-cost method to characterize the dissolution behavior of high-protein dairy powders.

  20. Emerging methods in proteomics: top-down protein characterization by multistage tandem mass spectrometry.

    PubMed

    Scherperel, Gwynyth; Reid, Gavin E

    2007-06-01

    "Top-down" mass spectrometry methods have emerged as an attractive alternative to conventional "bottom-up" approaches for the comprehensive characterization of co- and post-translational protein modifications. Here we present a brief overview of current strategies employed for top-down protein characterization and discuss the key technical challenges and solutions associated with their implementation on a range of mass spectrometry instrument platforms. For more specific details regarding the individual strategies described herein, interested readers are referred to the references cited at the end of this article.

  1. Multiple line arrays for the characterization of aeroacoustic sources using a time-reversal method.

    PubMed

    Mimani, A; Doolan, C J; Medwell, P R

    2013-10-01

    This letter investigates the use of multiple line arrays (LAs) in a Time-Reversal Mirror for localizing and characterizing multipole aeroacoustic sources in a uniform subsonic mean flow using a numerical Time-Reversal (TR) method. Regardless of the original source characteristics, accuracy of predicting the source location can be significantly improved using at least two LAs. Furthermore, it is impossible to determine the source characteristics using a single LA, rather a minimum of two are required to establish either the monopole or dipole source nature, while four LAs (fully surrounding the source) are required for characterizing a lateral quadrupole source.

  2. Characterization of a measurement reference standard and neutron fluence determination method in IRSN monoenergetic neutron fields

    NASA Astrophysics Data System (ADS)

    Gressier, V.; Lacoste, V.; Martin, A.; Pepino, M.

    2014-10-01

    The variation in the response of instruments with neutron energy has to be determined in well-characterized monoenergetic neutron fields. The quantities associated with these fields are the neutron fluence and the mean energy of the monoenergetic neutron peak needed to determine the related dosimetric quantities. At the IRSN AMANDE facility, the reference measurement standard for neutron fluence is based on a long counter calibrated in the IRSN reference 252Cf neutron field. In this paper, the final characterization of this device is presented as well as the method used to determine the reference fluence at the calibration point in monoenergetic neutron fields.

  3. Filtration characterization method as tool to assess membrane bioreactor sludge filterability-the delft experience.

    PubMed

    Lousada-Ferreira, Maria; Krzeminski, Pawel; Geilvoet, Stefan; Moreau, Adrien; Gil, Jose A; Evenblij, Herman; van Lier, Jules B; van der Graaf, Jaap H J M

    2014-04-30

    Prevention and removal of fouling is often the most energy intensive process in Membrane Bioreactors (MBRs), responsible for 40% to 50% of the total specific energy consumed in submerged MBRs. In the past decade, methods were developed to quantify and qualify fouling, aiming to support optimization in MBR operation. Therefore, there is a need for an evaluation of the lessons learned and how to proceed. In this article, five different methods for measuring MBR activated sludge filterability and critical flux are described, commented and evaluated. Both parameters characterize the fouling potential in full-scale MBRs. The article focuses on the Delft Filtration Characterization method (DFCm) as a convenient tool to characterize sludge properties, namely on data processing, accuracy, reproducibility, reliability, and applicability, defining the boundaries of the DFCm. Significant progress was made concerning fouling measurements in particular by using straight forward approaches focusing on the applicability of the obtained results. Nevertheless, a fouling measurement method is still to be defined which is capable of being unequivocal, concerning the fouling parameters definitions; practical and simple, in terms of set-up and operation; broad and useful, in terms of obtained results. A step forward would be the standardization of the aforementioned method to assess the sludge filtration quality.

  4. A new method for colors characterization of colored stainless steel using CIE and Munsell color systems

    NASA Astrophysics Data System (ADS)

    Ji, Keming; Xue, Yongqiang; Cui, Zixiang

    2015-09-01

    It is important to establish an accurate and comprehensive method of characterizing colors of colored stainless steel and understand the changing mechanism and the regularity of colors for the research, production and application of colored stainless steel. In this work, the method which combines reflectance-wavelength with both CIE and Munsell color systems is studied, the changing regularity of hue, brightness and saturation with increasing coloring potential differences is investigated, and the mechanism of color changing is discussed. The results show that by using this method the colors of colored stainless steel can be accurately and comprehensively characterized; with coloring potential differences and colored film thickness increasing, the peaks and troughs of the reflectance curves in visible region move toward long wave, causing the cyclically changing of hue and brightness; the amplitude of reflectance curves increases, resulting in growing of the saturation; the CIE 1931 coordinate curve of colors counterclockwise and cyclically changes around the equal energy light spot.

  5. Method of multi-dimensional moment analysis for the characterization of signal peaks

    SciTech Connect

    Pfeifer, Kent B; Yelton, William G; Kerr, Dayle R; Bouchier, Francis A

    2012-10-23

    A method of multi-dimensional moment analysis for the characterization of signal peaks can be used to optimize the operation of an analytical system. With a two-dimensional Peclet analysis, the quality and signal fidelity of peaks in a two-dimensional experimental space can be analyzed and scored. This method is particularly useful in determining optimum operational parameters for an analytical system which requires the automated analysis of large numbers of analyte data peaks. For example, the method can be used to optimize analytical systems including an ion mobility spectrometer that uses a temperature stepped desorption technique for the detection of explosive mixtures.

  6. A pump-and-probe method for the characterization of nonlinear material parameters within Fabry-Pérot microcavities

    NASA Astrophysics Data System (ADS)

    Gulde, Stephan; Jochim, Selim; Moll, Nikolaj; Mahrt, Rainer F.

    2006-08-01

    We present a pump-and-probe method based on optical Fabry-Pérot resonators that allows the characterization of third-order nonlinear materials relevant for all-optical technologies. The experiments show particular nonlinear optical resonator dynamics, which we analyze by numerical simulations. We highlight the pros and cons of our method compared with existing nonlinear material-characterization methods.

  7. Standardization of Nanoparticle Characterization: Methods for Testing Properties, Stability, and Functionality of Edible Nanoparticles.

    PubMed

    McClements, Jake; McClements, David Julian

    2016-06-10

    There has been a rapid increase in the fabrication of various kinds of edible nanoparticles for oral delivery of bioactive agents, such as those constructed from proteins, carbohydrates, lipids, and/or minerals. It is currently difficult to compare the relative advantages and disadvantages of different kinds of nanoparticle-based delivery systems because researchers use different analytical instruments and protocols to characterize them. In this paper, we briefly review the various analytical methods available for characterizing the properties of edible nanoparticles, such as composition, morphology, size, charge, physical state, and stability. This information is then used to propose a number of standardized protocols for characterizing nanoparticle properties, for evaluating their stability to environmental stresses, and for predicting their biological fate. Implementation of these protocols would facilitate comparison of the performance of nanoparticles under standardized conditions, which would facilitate the rational selection of nanoparticle-based delivery systems for different applications in the food, health care, and pharmaceutical industries.

  8. DOE assay methods used for characterization of contact-handled transuranic waste

    SciTech Connect

    Schultz, F.J. ); Caldwell, J.T. )

    1991-08-01

    US Department of Energy methods used for characterization of contact-handled transuranic (CH-TRU) waste prior to shipment to the Waste Isolation Pilot Plant (WIPP) are described and listed by contractor site. The methods described are part of the certification process. All CH-TRU waste must be assayed for determination of fissile material content and decay heat values prior to shipment and prior to storage on-site. Both nondestructive assay (NDA) and destructive assay methods are discussed, and new NDA developments such as passive-action neutron (PAN) crate counter improvements and neutron imaging are detailed. Specifically addressed are assay method physics; applicability to CH-TRU wastes; calibration standards and implementation; operator training requirements and practices; assay procedures; assay precision, bias, and limit of detection; and assay limitation. While PAN is a new technique and does not yet have established American Society for Testing and Materials. American National Standards Institute, or Nuclear Regulatory Commission guidelines or methods describing proper calibration procedures, equipment setup, etc., comparisons of PAN data with the more established assay methods (e.g., segmented gamma scanning) have demonstrated its reliability and accuracy. Assay methods employed by DOE have been shown to reliable and accurate in determining fissile, radionuclide, alpha-curie content, and decay heat values of CH-TRU wastes. These parameters are therefore used to characterize packaged waste for use in certification programs such as that used in shipment of CH-TRU waste to the WIPP. 36 refs., 10 figs., 7 tabs.

  9. Methods for Characterizing Participants’ Nonmainstream Dialect Use in Child Language Research

    PubMed Central

    Oetting, Janna B.; McDonald, Janet L.

    2012-01-01

    Three different approaches to the characterization of research participants’ nonmainstream dialect use can be found in the literature. They include listener judgment ratings, type-based counts of nonmainstream pattern use, and token-based counts. In this paper, we examined these three approaches, as well as shortcuts to these methods, using language samples from 93 children previously described in J. Oetting and J. McDonald (2001). Nonmainstream dialects represented in the samples included rural Louisiana versions of Southern White English (SWE) and Southern African American English (SAAE). Depending on the method and shortcut used, correct dialect classifications (SWE or SAAE) were made for 88% to 97% of the participants; however, regression algorithms had to be applied to the type- and token-based results to achieve these outcomes. For characterizing the rate at which the participants produced the nonmainstream patterns, the token-based methods were found to be superior to the others, but estimates from all approaches were moderately to highly correlated with each other. When type- and/or token-based methods were used to characterize participants’ dialect type and rate, the number of patterns included in the analyses could be substantially reduced without significantly affecting the validity of the outcomes. These findings have important implications for future child language studies that are done within the context of dialect diversity. PMID:12069003

  10. Analytical methods for characterization of explosives-contaminated sites on U.S. Army installations

    NASA Astrophysics Data System (ADS)

    Jenkins, Thomas F.; Walsh, Marianne E.; Thorne, Philip G.

    1995-10-01

    The U.S. Army manufactures munitions at facilities throughout the United States. Many of these facilities are contaminated with residues of explosives from production, disposal of off- specification, and out-of-data munitions. The first step in remediating these sites is careful characterization. Currently sites are being characterized using a combination of on-site field screening and off-site laboratory analysis. Most of the contamination is associated with TNT (2,4,6-trinitrotoluene) and RDX (hexahydro-1,3,5-tri-nitro-1,3,5-triazine) and their manufacturing impurities and environmental transformation products. Both colorimetric and enzyme immunoassay-based field screening methods have been used successfully for on-site characterization. These methods have similar detection capabilities but differ in their selectivity. Although field screening is very cost-effective, laboratory analysis is still required to fully characterize a site. Laboratory analysis for explosives residues in the United States is generally conducted using high-performance liquid chromatography equipped with a UV detector. Air-dried soils are extracted with acetonitrile in an ultrasonic bath. Water is analyzed directly if detection limits in the range of 10 - 20 (mu) g/L are acceptable, or preconcentrated using either salting-out solvent extraction with acetonitrile or solid phase extraction.

  11. A rapid method to characterize seabed habitats and associated macro-organisms

    USGS Publications Warehouse

    Anderson, T.J.; Cochrane, G.R.; Roberts, D.A.; Chezar, H.; Hatcher, G.; ,

    2007-01-01

    This study presents a method for rapidly collecting, processing, and interrogating real-time abiotic and biotic seabed data to determine seabed habitat classifications. This is done from data collected over a large area of an acoustically derived seabed map, along multidirectional transects, using a towed small camera-sled. The seabed, within the newly designated Point Harris Marine Reserve on the northern coast of San Miguel Island, California, was acoustically imaged using sidescan sonar then ground-truthed using a towed small camera-sled. Seabed characterizations were made from video observations, and were logged to a laptop computer (PC) in real time. To ground-truth the acoustic mosaic, and to characterize abiotic and biotic aspects of the seabed, a three-tiered characterization scheme was employed that described the substratum type, physical structure (i.e., bedform or vertical relief), and the occurrence of benthic macrofauna and flora. A crucial advantage of the method described here, is that preliminary seabed characterizations can be interrogated and mapped over the sidescan mosaic and other seabed information within hours of data collection. This ability to rapidly process seabed data is invaluable to scientists and managers, particularly in modifying concurrent or planning subsequent surveys.

  12. Borehole Fluid Logging Methods for Hydrogeologic Characterization: What Have We Learned in Twenty-Five Years?

    NASA Astrophysics Data System (ADS)

    Pedler, W. H.

    2012-12-01

    Over the past twenty-five years, several methods have been developed and enhanced to improve the capability to characterize hydraulically conductive intervals in wellbores. The principal, and most commonly employed, methods include the heat pulse flow meter, the electromagnetic flow meter, and hydrophysical (or FEC) logging. The primary objective of each of these methods is to identify the depth of the water bearing (conductive) intervals and estimate the volumetric flow rate of each conductive interval under one or more pressure conditions. The pressure conditions under which measurements are taken include ambient (native), pumping or injection of the subject well and/or pumping a well proximate to the subject (cross-hole testing). During this period, these methods have been applied in effectively all of the hydrogeologic systems including fractured bedrock, fractured sandstones, porous alluvium, massive and fractured clays, karst, and volcanics. Project applications range from contaminant fate and transport, geotechnical, mining and water supply. These methods evaluate flow in the wellbore fluid column by applying either stationary and/or profile-type logging measurements. Each of these methods evaluates flow in a distinct and unique way and, as such, there are limitations associated with each measurement method. The analytical methods to reduce the field data to the stated objectives also vary in complexity between the different methods. Numerous field and laboratory comparative studies have been conducted to evaluate, compare and verify the results of these methods. This poster will present a summary of these methods, recent updates, variety of applications and associated limitations.

  13. Mueller matrix holographic method for small particle characterization: theory and numerical studies.

    PubMed

    Gao, Meng; Yang, Ping; McKee, David; Kattawar, George W

    2013-07-20

    Holographic imaging has proved to be useful for spherical particle characterization, including the retrieval of particle size, refractive index, and 3D location. In this method, the interference pattern of the incident and scattered light fields is recorded by a camera and compared with the relevant Lorenz-Mie solutions. However, the method is limited to spherical particles, and the complete polarized scattering components have not been studied. This work extends the Mueller matrix formalism for the scattered light to describe the interference light field, and proposes a Mueller matrix holography method, through which complete polarization information can be obtained. The mathematical formalism of the holographic Mueller matrix is derived, and numerical examples of birefringent spheres are provided. The Mueller matrix holography method may provide a better opportunity than conventional methods to study anisotropic particles.

  14. Method for characterizing the coking tendencies of baseoils and additive-treated oils

    SciTech Connect

    Dickakian, G.B.

    1989-07-18

    This patent describes a method of characterizing the coking tendency of baseoil. The method consists the steps of: (a) subjecting the baseoil to conditions which accelerate asphaltene coke precursor formation in the baseoil, and (b) characterizing the coking tendency of the baseoil by determining (i) the onset and progression of asphaltene coke precursor formation as a function of time or (ii) the progression of asphaltene coke precursor formation as a function of time, wherein a faster onset of asphaltene coke precursor formation and a higher rate of asphaltene coke precursor formation or a higher rate of asphaltene coke precursor formation indicates a higher coking tendency of the baseoil than a slower onset of asphaltene coke precursor formation and a lower rate of asphaltene coke precursor formation or a lower rate of asphaltene coke precursor formation.

  15. A Novel Method for Characterization of Superconductors: Physical Measurements and Modeling of Thin Films

    NASA Technical Reports Server (NTRS)

    Kim, B. F.; Moorjani, K.; Phillips, T. E.; Adrian, F. J.; Bohandy, J.; Dolecek, Q. E.

    1993-01-01

    A method for characterization of granular superconducting thin films has been developed which encompasses both the morphological state of the sample and its fabrication process parameters. The broad scope of this technique is due to the synergism between experimental measurements and their interpretation using numerical simulation. Two novel technologies form the substance of this system: the magnetically modulated resistance method for characterizing superconductors; and a powerful new computer peripheral, the Parallel Information Processor card, which provides enhanced computing capability for PC computers. This enhancement allows PC computers to operate at speeds approaching that of supercomputers. This makes atomic scale simulations possible on low cost machines. The present development of this system involves the integration of these two technologies using mesoscale simulations of thin film growth. A future stage of development will incorporate atomic scale modeling.

  16. Ptychographic phase retrieval method for characterizing ultra-precise ellipsoidal mirrors

    NASA Astrophysics Data System (ADS)

    Takeo, Yoko; Saito, Takahiro; Mimura, Hidekazu

    2015-10-01

    Focusing and imaging optics can be characterized by evaluating the wavefront error of the focused beam. We have bean developing a ptychographic phase retrieval method using a visible laser to measure the wavefront error. In this study, the measurement accuracy of the method is increased by improving both the phase retrieval algorithm and the experimental setup. The system is applied to the characterization of an ellipsoidal mirror used for the focusing of soft X-rays. The posture of the mirror can be measured with a resolution of 1.4 μrad. The wavefront error originating from the surface profile error can be detected with an accuracy of 0.01λ (root mean square).

  17. "METHOD": A tool for mechanical, electrical, thermal, and optical characterization of single lens module design

    NASA Astrophysics Data System (ADS)

    Besson, Pierre; Dominguez, Cesar; Voarino, Philippe; Garcia-Linares, Pablo; Weick, Clement; Lemiti, Mustapha; Baudrit, Mathieu

    2015-09-01

    The optical characterization and electrical performance evaluation are essential in the design and optimization of a concentrator photovoltaic system. The geometry, materials, and size of concentrator optics are diverse and different environmental conditions impact their performance. CEA has developed a new concentrator photovoltaic system characterization bench, METHOD, which enables multi-physics optimization studies. The lens and cell temperatures are controlled independently with the METHOD to study their isolated effects on the electrical and optical performance of the system. These influences can be studied in terms of their effect on optical efficiency, focal distance, spectral sensitivity, electrical efficiency, or cell current matching. Furthermore, the irradiance map of a concentrator optic can be mapped to study its variations versus the focal length or the lens temperature. The present work shows this application to analyze the performance of a Fresnel lens linking temperature to optical and electrical performance.

  18. Use of an open-ended coaxial cavity method to characterize powdery substances exposed to humidity

    NASA Astrophysics Data System (ADS)

    Tuhkala, M.; Juuti, J.; Jantunen, H.

    2013-09-01

    The effect of moisture adsorption in the characterization of dielectric powders by an indirectly coupled open-ended coaxial cavity method operating at 4.5 GHz was analyzed. SiO2, Al2O3, and ZrO2 powders were exposed to 5% and 100% relative humidity levels and Bruggeman symmetric, Looyenga, and General Mixing Model equations were used to determine changes in permittivity and loss tangent of the inclusions. Low moisture adsorption (0.1-2.5 vol. %) induced only a small change in inclusion permittivity but had a pronounced impact on dielectric losses. Calculated moisture percentages based on responses of the resonator and the General Mixing Model correlated well with traditional mass based determination. The presented characterization method exhibited high sensitivity for the determination of dielectric properties of powders and their moisture content to be further utilized in, e.g., process and quality monitoring.

  19. Field Demonstrations of Five Geophysical Methods that Could Be Used to Characterize Deposits of Alluvial Aggregate

    USGS Publications Warehouse

    Ellefsen, K.J.; Burton, B.L.; Lucius, J.E.; Haines, S.S.; Fitterman, D.V.; Witty, J.A.; Carlson, D.; Milburn, B.; Langer, W.H.

    2007-01-01

    Personnel from the U.S. Geological Survey and Martin Marietta Aggregates, Inc., conducted field demonstrations of five different geophysical methods to show how these methods could be used to characterize deposits of alluvial aggregate. The methods were time-domain electromagnetic sounding, electrical resistivity profiling, S-wave reflection profiling, S-wave refraction profiling, and P-wave refraction profiling. All demonstrations were conducted at one site within a river valley in central Indiana, where the stratigraphy consisted of 1 to 2 meters of clay-rich soil, 20 to 35 meters of alluvial sand and gravel, 1 to 6 meters of clay, and multiple layers of limestone and dolomite bedrock. All geophysical methods, except time-domain electromagnetic sounding, provided information about the alluvial aggregate that was consistent with the known geology. Although time-domain electromagnetic sounding did not work well at this site, it has worked well at other sites with different geology. All of these geophysical methods complement traditional methods of geologic characterization such as drilling.

  20. On the application of Allan variance method for Ring Laser Gyro performance characterization

    SciTech Connect

    Ng, L.C.

    1993-10-15

    This report describes the method of Allan variance and its application to the characterization of a Ring Laser Gyro`s (RLG) performance. Allan variance, a time domain analysis technique, is an accepted IEEE standard for gyro specifications. The method was initially developed by David Allan of the National Bureau of Standards to quantify the error statistics of a Cesium beam frequency standard employed as the US Frequency Standards in 1960`s. The method can, in general, be applied to analyze the error characteristics of any precision measurement instrument. The key attribute of the method is that it allows for a finer, easier characterization and identification of error sources and their contribution to the overall noise statistics. This report presents an overview of the method, explains the relationship between Allan variance and power spectral density distribution of underlying noise sources, describes the batch and recursive implementation approaches, validates the Allan variance computation with a simulation model, and illustrates the Allan variance method using data collected from several Honeywell LIMU units.

  1. Surface topography characterization of automotive cylinder liner surfaces using fractal methods

    NASA Astrophysics Data System (ADS)

    Lawrence K, Deepak; Ramamoorthy, B.

    2013-09-01

    This paper explores the use of fractal approaches for the possible characterization of automotive cylinder bore surface topography by employing methods such as differential box counting method, power spectral method and structure function method. Three stage plateau honing experiments were conducted to manufacture sixteen cylinder liner surfaces with different surface topographies, for the study. The three fractal methods are applied on the image data obtained using a computer vision system and 3-D profile data obtained using vertical scanning white light interferometer from the cylinder liner surfaces. The computed fractal parameters (fractal dimension and topothesy) are compared and correlated with the measured 3-D Abbott-Firestone curve parameters (Sk, Spk, Svk, Sr1 and Sr2) that are currently used for the surface topography characterization cylinder liner surfaces. The analyses of the results indicated that the fractal dimension (D) computed using the vision data as well as 3-D profile data by employing three different fractal methods consistantly showed a negative correlation with the functional surface topographical parameters that represents roughness at peak (Spk),core (Sk) and valley (Svk) regions and positive correlation with the upper bearing area (Sr1) and lower bearing area (Sr2) of the automotive of cylinder bore surface.

  2. Optimal mask characterization by Surrogate Wafer Print (SWaP) method

    NASA Astrophysics Data System (ADS)

    Kimmel, Kurt R.; Hoellein, Ingo; Peters, Jan Hendrick; Ackmann, Paul; Connolly, Brid; West, Craig

    2008-10-01

    Traditionally, definition of mask specifications is done completely by the mask user, while characterization of the mask relative to the specifications is done completely by the mask maker. As the challenges of low-k1 imaging continue to grow in scope of designs and in absolute complexity, the inevitable partnership between wafer lithographers and mask makers has strengthened as well. This is reflected in the jointly owned mask facilities and device manufacturers' continued maintenance of fully captive mask shops which foster the closer mask-litho relationships. However, while some device manufacturers have leveraged this to optimize mask specifications before the mask is built and, therefore, improve mask yield and cost, the opportunity for post-fabrication partnering on mask characterization is more apparent and compelling. The Advanced Mask Technology Center (AMTC) has been investigating the concept of assessing how a mask images, rather than the mask's physical attributes, as a technically superior and lower-cost method to characterize a mask. The idea of printing a mask under its intended imaging conditions, then characterizing the imaged wafer as a surrogate for traditional mask inspections and measurements represents the ultimate method to characterize a mask's performance, which is most meaningful to the user. Surrogate wafer print (SWaP) is already done as part of leading-edge wafer fab mask qualification to validate defect and dimensional performance. In the past, the prospect of executing this concept has generally been summarily discarded as technically untenable and logistically intractable. The AMTC published a paper at BACUS 2007 successfully demonstrating the performance of SWaP for the characterization of defects as an alternative to traditional mask inspection [1]. It showed that this concept is not only feasible, but, in some cases, desirable. This paper expands on last year's work at AMTC to assess the full implementation of SWaP as an

  3. Method for in situ characterization of a medium of dispersed matter in a continuous phase

    DOEpatents

    Kaufman, E.N.

    1995-03-07

    A method is described for the in situ characterization of a medium of a dispersed phase in a continuous phase, including the steps of adding a fluorescent dye to one phase capable of producing fluorescence therein when the fluorescent dye is optically excited, optically exciting the fluorescent dye at a wavelength to produce fluorescence in the one phase, and monitoring the fluorescence to distinguish the continuous phase from the dispersed phase. 2 figs.

  4. Method for in situ characterization of a medium of dispersed matter in a continuous phase

    DOEpatents

    Kaufman, Eric N.

    1995-01-01

    A method for in situ characterization of a medium of a dispersed phase in a continuous phase, including the steps of adding a fluorescent dye to one phase capable of producing fluorescence therein when the fluorescent dye is optically excited, optically exciting the fluorescent dye at a wavelength to produce fluorescence in the one phase, and monitoring the fluorescence to distinguish the continuous phase from the dispersed phase.

  5. Improving Protection against Viral Aerosols Through Development of Novel Decontamination Methods and Characterization of Viral Aerosol

    DTIC Science & Technology

    2012-04-01

    AFRL-RX-TY-TP-2012-0040 IMPROVING PROTECTION AGAINST VIRAL AEROSOLS THROUGH DEVELOPMENT OF NOVEL DECONTAMINATION METHODS AND CHARACTERIZATION...Include area code) 16-APR-2012 Technical Paper (Thesis) 15-SEP-2007 -- 30-APR-2012 Improving Protection against Viral Aerosols Through Development of...medium showed that artificial saliva (AS) and beef serum extract (BE) produce a protective effect against UV compared to deionized (DI) water, that RH was

  6. Method and Characterization of Pyroelectric Coefficients for Determining Material Figures of Merit for Infrared (IR) Detectors

    DTIC Science & Technology

    2013-12-01

    iii Contents List of Figures iv 1. Introduction 1 2. Pyroelectric Effect 2 3. IR Detector Figure-of-Merits 2 4. Pyroelectric Measurement 4 5...accuracy and internal consistency of the characterization setup. Also, the basic pyroelectric effect , the material FoM for pyroelectric detectors...and methods to measure the material pyroelectric coefficient are briefly reviewed. 2. Pyroelectric Effect Pyroelectricity is a property of polar

  7. Quantitative Methods for Reservoir Characterization and Improved Recovery: Application to Heavy Oil Sands

    SciTech Connect

    Castle, James W.; Molz, Fred J.

    2003-02-07

    Improved prediction of interwell reservoir heterogeneity is needed to increase productivity and to reduce recovery cost for California's heavy oil sands, which contain approximately 2.3 billion barrels of remaining reserves in the Temblor Formation and in other formations of the San Joaquin Valley. This investigation involved application of advanced analytical property-distribution methods conditioned to continuous outcrop control for improved reservoir characterization and simulation.

  8. Comparison of Molecular and Phenotypic Methods for the Detection and Characterization of Carbapenem Resistant Enterobacteriaceae.

    PubMed

    Somily, Ali M; Garaween, Ghada A; Abukhalid, Norah; Absar, Muhammad M; Senok, Abiola C

    2016-03-01

    In recent years, there has been a rapid dissemination of carbapenem resistant Enterobacteriaceae (CRE). This study aimed to compare phenotypic and molecular methods for detection and characterization of CRE isolates at a large tertiary care hospital in Saudi Arabia. This study was carried out between January 2011 and November 2013 at the King Khalid University Hospital (KKUH) in Saudi Arabia. Determination of presence of extended-spectrum beta-lactamases (ESBL) and carbapenem resistance was in accordance with Clinical and Laboratory Standards Institute (CLSI) guidelines. Phenotypic classification was done by the MASTDISCS(TM) ID inhibitor combination disk method. Genotypic characterization of ESBL and carbapenemase genes was performed by the Check-MDR CT102. Diversilab rep-PCR was used for the determination of clonal relationship. Of the 883 ESBL-positive Enterobacteriaceae detected during the study period, 14 (1.6%) isolates were carbapenem resistant. Both the molecular genotypic characterization and phenotypic testing were in agreement in the detection of all 8 metalo-beta-lactamases (MBL) producing isolates. Of these 8 MBL-producers, 5 were positive for blaNDM gene and 3 were positive for blaVIM gene. Molecular method identified additional blaOXA gene isolates while MASTDISCS(TM) ID detected one AmpC producer isolate. Both methods agreed in identifying 2 carbapenem resistant isolates which were negative for carbapenemase genes. Diversilab rep-PCR analysis of the 9 Klebsiella pneumoniae isolates revealed polyclonal distribution into eight clusters. MASTDISCS(TM) ID is a reliable simple cheap phenotypic method for detection of majority of carbapenemase genes with the exception of the blaOXA gene. We recommend to use such method in the clinical laboratory.

  9. Electro-Optical Sensing Apparatus and Method for Characterizing Free-Space Electromagnetic Radiation

    DOEpatents

    Zhang, Xi-Cheng; Libelo, Louis Francis; Wu, Qi

    1999-09-14

    Apparatus and methods for characterizing free-space electromagnetic energy, and in particular, apparatus/method suitable for real-time two-dimensional far-infrared imaging applications are presented. The sensing technique is based on a non-linear coupling between a low-frequency electric field and a laser beam in an electro-optic crystal. In addition to a practical counter-propagating sensing technique, a co-linear approach is described which provides longer radiated field--optical beam interaction length, thereby making imaging applications practical.

  10. Methods for Quantifying and Characterizing Errors in Pixel-Based 3D Rendering.

    PubMed

    Hagedorn, John G; Terrill, Judith E; Peskin, Adele P; Filliben, James J

    2008-01-01

    We present methods for measuring errors in the rendering of three-dimensional points, line segments, and polygons in pixel-based computer graphics systems. We present error metrics for each of these three cases. These methods are applied to rendering with OpenGL on two common hardware platforms under several rendering conditions. Results are presented and differences in measured errors are analyzed and characterized. We discuss possible extensions of this error analysis approach to other aspects of the process of generating visual representations of synthetic scenes.

  11. Nonlinear optical characterization of ZnS thin film synthesized by chemical spray pyrolysis method

    NASA Astrophysics Data System (ADS)

    G, Sreeja V.; V, Sabitha P.; Anila, E. I.; R, Reshmi; John, Manu Punnan; Radhakrishnan, P.

    2014-10-01

    ZnS thin film was prepared by Chemical Spray Pyrolysis (CSP) method. The sample was characterized by X-ray diffraction method and Z scan technique. XRD pattern showed that ZnS thin film has hexagonal structure with an average size of about 5.6nm. The nonlinear optical properties of ZnS thin film was studied by open aperture Z-Scan technique using Q-switched Nd-Yag Laser at 532nm. The Z-scan plot showed that the investigated ZnS thin film has saturable absorption behavior. The nonlinear absorption coefficient and saturation intensity were also estimated.

  12. Characterization of single-wall carbon nanotubes produced by CCVD method

    NASA Astrophysics Data System (ADS)

    Colomer, J.-F.; Benoit, J.-M.; Stephan, C.; Lefrant, S.; Van Tendeloo, G.; Nagy, J. B.

    2001-09-01

    Carbon single-wall nanotubes (SWNTs) can be produced by the catalytic chemical vapor deposition (CCVD) method. They are synthesized by catalytic decomposition of methane at 1000 °C on 2.5 wt% Co/MgO catalyst. SWNT samples have been characterized by transmission electron microscopy (TEM) and Raman spectroscopy. Using these two techniques, a comparison between the SWNTs produced by CCVD and synthesized by electric arc discharge has been made. Finally, we give conclusions about the diameter distribution and the electronic structure of SWNTs produced by the CCVD method.

  13. Nonlinear optical characterization of ZnS thin film synthesized by chemical spray pyrolysis method

    SciTech Connect

    G, Sreeja V; Anila, E. I. R, Reshmi John, Manu Punnan; V, Sabitha P; Radhakrishnan, P.

    2014-10-15

    ZnS thin film was prepared by Chemical Spray Pyrolysis (CSP) method. The sample was characterized by X-ray diffraction method and Z scan technique. XRD pattern showed that ZnS thin film has hexagonal structure with an average size of about 5.6nm. The nonlinear optical properties of ZnS thin film was studied by open aperture Z-Scan technique using Q-switched Nd-Yag Laser at 532nm. The Z-scan plot showed that the investigated ZnS thin film has saturable absorption behavior. The nonlinear absorption coefficient and saturation intensity were also estimated.

  14. Analysis of parity between protein-based electrophoretic methods for the characterization of oral Candida species.

    PubMed

    Rosa, E A; Rosa, R T; Pereira, C V; Boriollo, M F; Höfling, J F

    2000-01-01

    Electrophoretic studies of multilocus-enzymes (MLEE) and whole-cell protein (SDS-PAGE) were carried out in order to evaluate the parity between different methods for the characterization of five Candida species commonly isolated from oral cavity of humans by numerical taxonomy methods. The obtained data revealed that sodium dodecyl sulfate polyacrylamide gel electrophoresis is more efficient in grouping strains in their respective species while MLEE has much limited resolution in organizing all strains in their respective species-specific clusters. MLEE technique must be regarded for surveys in which just one species of Candida is involved.

  15. Material grain size characterization method based on energy attenuation coefficient spectrum and support vector regression.

    PubMed

    Li, Min; Zhou, Tong; Song, Yanan

    2016-07-01

    A grain size characterization method based on energy attenuation coefficient spectrum and support vector regression (SVR) is proposed. First, the spectra of the first and second back-wall echoes are cut into several frequency bands to calculate the energy attenuation coefficient spectrum. Second, the frequency band that is sensitive to grain size variation is determined. Finally, a statistical model between the energy attenuation coefficient in the sensitive frequency band and average grain size is established through SVR. Experimental verification is conducted on austenitic stainless steel. The average relative error of the predicted grain size is 5.65%, which is better than that of conventional methods.

  16. Methods for characterizing magnetic footprints of perpendicular magnetic recording writer heads

    SciTech Connect

    Li, Shaoping Lin, Ed; George, Zach; Terrill, Dave; Mendez, H.; Santucci, J.; Yie, Derek

    2014-05-07

    In this work, the magnetic footprints, along with some of its dynamic features in recording process, of perpendicular magnetic recording writer heads have been characterized by using three different techniques. Those techniques are the spin-stand stationary footprint technique, the spin-stand dynamic footprint technique, and the coherent writing technique combined with magnetic force microscope imaging method. The characteristics of those techniques have been compared to one another. It was found experimentally that the spin-stand stationary method could not precisely catch some peculiar recording dynamics of the write heads in certain conditions. The advantages and disadvantages among all those techniques are also examined and discussed in detail.

  17. Electrically conductive proppant and methods for detecting, locating and characterizing the electrically conductive proppant

    DOEpatents

    Cannan, Chad; Bartel, Lewis; Palisch, Terrence; Aldridge, David

    2015-01-13

    Electrically conductive proppants and methods for detecting, locating, and characterizing same are provided. The electrically conductive proppant can include a substantially uniform coating of an electrically conductive material having a thickness of at least 500 nm. The method can include injecting a hydraulic fluid into a wellbore extending into a subterranean formation at a rate and pressure sufficient to open a fracture therein, injecting into the fracture a fluid containing the electrically conductive proppant, electrically energizing the earth at or near the fracture, and measuring three dimensional (x, y, and z) components of electric and magnetic field responses at a surface of the earth or in an adjacent wellbore.

  18. Complementary MS Methods Assist Conformational Characterization of Antibodies with Altered S-S Bonding Networks

    NASA Astrophysics Data System (ADS)

    Jones, Lisa M.; Zhang, Hao; Cui, Weidong; Kumar, Sandeep; Sperry, Justin B.; Carroll, James A.; Gross, Michael L.

    2013-06-01

    As therapeutic monoclonal antibodies (mAbs) become a major focus in biotechnology and a source of the next-generation drugs, new analytical methods or combination methods are needed for monitoring changes in higher order structure and effects of post-translational modifications. The complexity of these molecules and their vulnerability to structural change provide a serious challenge. We describe here the use of complementary mass spectrometry methods that not only characterize mutant mAbs but also may provide a general framework for characterizing higher order structure of other protein therapeutics and biosimilars. To frame the challenge, we selected members of the IgG2 subclass that have distinct disulfide isomeric structures as a model to evaluate an overall approach that uses ion mobility, top-down MS sequencing, and protein footprinting in the form of fast photochemical oxidation of proteins (FPOP). These three methods are rapid, sensitive, respond to subtle changes in conformation of Cys → Ser mutants of an IgG2, each representing a single disulfide isoform, and may be used in series to probe higher order structure. The outcome suggests that this approach of using various methods in combination can assist the development and quality control of protein therapeutics.

  19. An evaporation study for phthalic acids--a rapid method for pharmaceutical characterization.

    PubMed

    Chatterjee, Koustuv; Hazra, Anasuya; Dollimore, David; Alexander, Kenneth S

    2002-04-01

    The objective of this study was to develop and analyze an analytical method in order to evaluate preformulation candidates by their thermodynamic parameters and evaporation characteristics. Ortho, meta and tere-phthalic acids were chosen as model compounds. The relative advantages and disadvantages of a rapid thermogravimetric method have been studied in detail, which would aid in the preformulation characterization for pharmaceuticals. Methyl paraben was taken as the model compound for calibration, as its evaporation characteristics are well known. Using the Antoine and the Langmuir equation for evaporation conjointly, the parameter k, known as the coefficient of evaporation was determined. The value for this constant was validated by three methods simultaneously. Previously the use of such methods for compounds having uninhibited zero order evaporation has been documented. In the present study, phthalic acid was chosen as the model compound since its evaporation is a two-step overlapping phenomenon. In this study we have shown the use of Pressure Differential Scanning Calorimetry in separating such simultaneous endothermic processes. The Clausius-Clapeyron equation seemingly has anomalous behavior for vapor pressure over high temperature ranges. In this study a modification of the equation has been suggested to take into account the changes in the heat capacities that result due to high temperature effects. This study aims at documenting a concise method for rapid pharmaceutical characterization and suggests modifications for some basic thermodynamic parameters over higher temperature ranges.

  20. Complementary MS Methods Assist Conformational Characterization of Antibodies with Altered S–S Bonding Networks

    PubMed Central

    Jones, Lisa M.; Zhang, Hao; Cui, Weidong; Kumar, Sandeep; Sperry, Justin B.; Carroll, James A.; Gross, Michael L.

    2013-01-01

    As therapeutic monoclonal antibodies (mAbs) become a major focus in biotechnology and a source of the next-generation drugs, new analytical methods or combination methods are needed for monitoring changes in higher order structure and effects of post-translational modifications. The complexity of these molecules and their vulnerability to structural change provide a serious challenge. We describe here the use of complementary mass spectrometry methods that not only characterize mutant mAbs but also may provide a general framework for characterizing higher order structure of other protein therapeutics and biosimilars. To frame the challenge, we selected members of the IgG2 subclass that have distinct disulfide isomeric structures as a model to evaluate an overall approach that uses ion mobility, top-down MS sequencing, and protein footprinting in the form of fast photochemical oxidation of proteins (FPOP). These three methods are rapid, sensitive, respond to subtle changes in conformation of Cys→Ser mutants of an IgG2, each representing a single disulfide isoform, and may be used in series to probe higher order structure. The outcome suggests that this approach of using various methods in combination can assist the development and quality control of protein therapeutics. PMID:23483515

  1. Comparison of microcrystalline characterization results from oil palm midrib alpha cellulose using different delignization method

    NASA Astrophysics Data System (ADS)

    Yuliasmi, S.; Pardede, T. R.; Nerdy; Syahputra, H.

    2017-03-01

    Oil palm midrib is one of the waste generated by palm plants containing 34.89% cellulose. Cellulose has the potential to produce microcrystalline cellulose can be used as an excipient in tablet formulations by direct compression. Microcrystalline cellulose is the result of a controlled hydrolysis of alpha cellulose, so the alpha cellulose extraction process of oil palm midrib greatly affect the quality of the resulting microcrystalline cellulose. The purpose of this study was to compare the microcrystalline cellulose produced from alpha cellulose extracted from oil palm midrib by two different methods. Fisrt delignization method uses sodium hydroxide. Second method uses a mixture of nitric acid and sodium nitrite, and continued with sodium hydroxide and sodium sulfite. Microcrystalline cellulose obtained by both method was characterized separately, including organoleptic test, color reagents test, dissolution test, pH test and determination of functional groups by FTIR. The results was compared with microcrystalline cellulose which has been available on the market. The characterization results showed that microcrystalline cellulose obtained by first method has the most similar characteristics to the microcrystalline cellulose available in the market.

  2. X-ray based methods for non-destructive testing and material characterization

    NASA Astrophysics Data System (ADS)

    Hanke, Randolf; Fuchs, Theobald; Uhlmann, Norman

    2008-06-01

    The increasing complexity and miniaturization in the field of new materials as well as in micro-production requires in the same way improvements and technical advances in the field of micro-NDT to provide better quality data and more detailed knowledge about the internal structures of micro-components. Therefore, non-destructive methods like radioscopy, ultrasound, optical or thermal imaging increasingly gain in importance with respect to ongoing product and material development in the different phases like material characterization, production control or module reliability testing. Because of the manifold different application fields, i.e., certain physical NDT methods applied to material inspection, characterization or reliability testing, this contribution will focus on the radioscopic-based methods related to their most important applications. Today, in modern industrial quality control, X-ray transmission is used in two different ways: Two-dimensional radioscopic transmission imaging (projection technique), usually applied to inline inspection tasks in application fields like lightweight material production, electronic component soldering or food production. Computed tomography (CT) for generation of three-dimensional data, representing spatial information and density distribution of objects. CT application fields are on the one hand the understanding of production process failure or component and module inspection (completeness) and on the other hand the dimensional measuring of hidden geometrical outlines (metrology). This paper demonstrates the methods including technical set-ups (X-ray source and detector), imaging and reconstruction results and the methods for high speed and high-resolution volume data generation and evaluation.

  3. Subsurface and Surface Characterization using an Information Framework Model

    NASA Astrophysics Data System (ADS)

    Samuel-Ojo, Olusola

    inelastic deformations under the influence of an underlying geologic southward plate motion within the theory of plate tectonics. It also explains the impact of a history of heavy pumpage of groundwater during the agricultural and urbanization era. Thus the persistent scatterer interferometry method offers an attractive, non-intrusive, cost-effective augmentation of the conventional method of monitoring groundwater for water resource development and stability of soil mass.

  4. Beyond van der Pauw: Novel methods for four-point magnetotransport characterization

    NASA Astrophysics Data System (ADS)

    Zhou, Wang

    In this thesis, the conventional four-point measurement technique and the van der Pauw (vdP) method are systematically investigated in the presence of non-ideal conditions, namely, non-uniform carrier density distribution and absence of ohmic contacts, which are nonetheless commonly encountered in semiconductor characterizations. Upon understanding the challenges in the conventional methods, novel characterization techniques are developed to address these challenges. A longitudinal magnetoresistance asymmetry method was developed to study the carrier density non-uniformity in two-dimensional samples. By analyzing the asymmetric longitudinal magnetoresistance under positive and negative B-fields, an analytical model based on a linear density gradient across the sample was deduced to quantitatively describe the asymmetry. Based on the theoretical model, a practical method was described which enabled one to experimentally measure the density gradient within a single sample. The method requires only measurements of longitudinal resistances R xx and Ryy under both positive and negative B-fields, and equations have been provided to extract both the angle and the magnitude of density gradients from the measured resistances. The method was demonstrated in a GaAs quantum well wafer at cryogenic temperatures and n-GaAs bulk-doped wafer at room temperature. In both systems, the density gradient vectors extracted with our method matched well with the interpolated density gradient vectors estimated from actual density distribution maps as a base comparison set, suggesting that our method can be a universal extension of the vdP method to extract density gradients in various systems. The method also allows one to uncover the true local longitudinal resistivity rhoxx at the center of the sample, which the conventional vdP method cannot describe in the presence of non-uniform densities. The ability to find rhoxx makes it possible to study interesting physics in semiconductors such

  5. Error baseline rates of five sample preparation methods used to characterize RNA virus populations.

    PubMed

    Kugelman, Jeffrey R; Wiley, Michael R; Nagle, Elyse R; Reyes, Daniel; Pfeffer, Brad P; Kuhn, Jens H; Sanchez-Lockhart, Mariano; Palacios, Gustavo F

    2017-01-01

    Individual RNA viruses typically occur as populations of genomes that differ slightly from each other due to mutations introduced by the error-prone viral polymerase. Understanding the variability of RNA virus genome populations is critical for understanding virus evolution because individual mutant genomes may gain evolutionary selective advantages and give rise to dominant subpopulations, possibly even leading to the emergence of viruses resistant to medical countermeasures. Reverse transcription of virus genome populations followed by next-generation sequencing is the only available method to characterize variation for RNA viruses. However, both steps may lead to the introduction of artificial mutations, thereby skewing the data. To better understand how such errors are introduced during sample preparation, we determined and compared error baseline rates of five different sample preparation methods by analyzing in vitro transcribed Ebola virus RNA from an artificial plasmid-based system. These methods included: shotgun sequencing from plasmid DNA or in vitro transcribed RNA as a basic "no amplification" method, amplicon sequencing from the plasmid DNA or in vitro transcribed RNA as a "targeted" amplification method, sequence-independent single-primer amplification (SISPA) as a "random" amplification method, rolling circle reverse transcription sequencing (CirSeq) as an advanced "no amplification" method, and Illumina TruSeq RNA Access as a "targeted" enrichment method. The measured error frequencies indicate that RNA Access offers the best tradeoff between sensitivity and sample preparation error (1.4-5) of all compared methods.

  6. Growth and characterization of unidirectional (100) KDP single crystal by Sankaranarayanan-Ramasamy (SR) method.

    PubMed

    Balamurugan, S; Ramasamy, P

    2009-01-01

    Unidirectional (100) potassium dihydrogen orthophosphate (KDP) single crystals were grown by Sankaranarayanan-Ramasamy (SR) method. The (100) oriented seed crystals were mounted at the bottom of the glass ampoules and the crystals of 20mm diameter, 30 mm height and 15 mm diameter, 65 mm height were grown by SR method. The grown crystals were characterized by high-resolution X-ray diffractometry anlaysis, UV-vis spectroscopy, dielectric and microhardness studies. The high-resolution X-ray diffractometry anlaysis indicates that the crystalline perfection is excellent without having any very low angle internal structural grain boundaries. The SR method-grown unidirectional KDP has 15% higher transmittance compared to conventional method-grown crystals. The dielectric constant was higher and the dielectric loss was less in SR method-grown crystal. The crystals grown by SR method have much higher hardness value than conventional method-grown crystals. The quality of the crystal grown by SR method is better than conventional method-grown crystal.

  7. Instructional Review: An Introduction to Optical Methods for Characterizing Liquid Crystals at Interfaces

    PubMed Central

    Miller, Daniel S.; Carlton, Rebecca J.; Mushenheim, Peter C.; Abbott, Nicholas L.

    2013-01-01

    This Instructional Review describes methods and underlying principles that can be used to characterize both the orientations assumed spontaneously by liquid crystals (LCs) at interfaces and the strength with which the LCs are held in those orientations (so-called anchoring energies). The application of these methods to several different classes of LC interfaces is described, including solid and aqueous interfaces as well as planar and non-planar interfaces (such as those that define a LC-in-water emulsion droplet). These methods, which enable fundamental studies of the ordering of LCs at polymeric, chemically-functionalized and biomolecular interfaces, are described in this article at a level that can be easily understood by a non-expert reader such as an undergraduate or graduate student. We focus on optical methods because they are based on instrumentation that is found widely in research and teaching laboratories. PMID:23347378

  8. Characterization, thermal stability studies, and analytical method development of Paromomycin for formulation development.

    PubMed

    Khan, Wahid; Kumar, Neeraj

    2011-06-01

    Paromomycin (PM) is an aminoglycoside antibiotic, first isolated in the 1950s, and approved in 2006 for treatment of visceral leishmaniasis. Although isolated six decades back, sufficient information essential for development of pharmaceutical formulation is not available for PM. The purpose of this paper was to determine thermal stability and development of new analytical method for formulation development of PM. PM was characterized by thermoanalytical (DSC, TGA, and HSM) and by spectroscopic (FTIR) techniques and these techniques were used to establish thermal stability of PM after heating PM at 100, 110, 120, and 130 °C for 24 h. Biological activity of these heated samples was also determined by microbiological assay. Subsequently, a simple, rapid and sensitive RP-HPLC method for quantitative determination of PM was developed using pre-column derivatization with 9-fluorenylmethyl chloroformate. The developed method was applied to estimate PM quantitatively in two parenteral dosage forms. PM was successfully characterized by various stated techniques. These techniques indicated stability of PM for heating up to 120 °C for 24 h, but when heated at 130 °C, PM is liable to degradation. This degradation is also observed in microbiological assay where PM lost ∼30% of its biological activity when heated at 130 °C for 24 h. New analytical method was developed for PM in the concentration range of 25-200 ng/ml with intra-day and inter-day variability of < 2%RSD. Characterization techniques were established and stability of PM was determined successfully. Developed analytical method was found sensitive, accurate, and precise for quantification of PM. Copyright © 2010 John Wiley & Sons, Ltd.

  9. Non-contact method for characterization of small size thermoelectric modules

    NASA Astrophysics Data System (ADS)

    Manno, Michael; Yang, Bao; Bar-Cohen, Avram

    2015-08-01

    Conventional techniques for characterization of thermoelectric performance require bringing measurement equipment into direct contact with the thermoelectric device, which is increasingly error prone as device size decreases. Therefore, the novel work presented here describes a non-contact technique, capable of accurately measuring the maximum ΔT and maximum heat pumping of mini to micro sized thin film thermoelectric coolers. The non-contact characterization method eliminates the measurement errors associated with using thermocouples and traditional heat flux sensors to test small samples and large heat fluxes. Using the non-contact approach, an infrared camera, rather than thermocouples, measures the temperature of the hot and cold sides of the device to determine the device ΔT and a laser is used to heat to the cold side of the thermoelectric module to characterize its heat pumping capacity. As a demonstration of the general applicability of the non-contact characterization technique, testing of a thin film thermoelectric module is presented and the results agree well with those published in the literature.

  10. Qualitative and quantitative characterization of protein-phosphoinositide interactions with liposome-based methods.

    PubMed

    Busse, Ricarda A; Scacioc, Andreea; Hernandez, Javier M; Krick, Roswitha; Stephan, Milena; Janshoff, Andreas; Thumm, Michael; Kühnel, Karin

    2013-05-01

    We characterized phosphoinositide binding of the S. cerevisiae PROPPIN Hsv2 qualitatively with density flotation assays and quantitatively through isothermal titration calorimetry (ITC) measurements using liposomes. We discuss the design of these experiments and show with liposome flotation assays that Hsv2 binds with high specificity to both PtdIns3P and PtdIns(3,5)P 2. We propose liposome flotation assays as a more accurate alternative to the commonly used PIP strips for the characterization of phosphoinositide-binding specificities of proteins. We further quantitatively characterized PtdIns3P binding of Hsv2 with ITC measurements and determined a dissociation constant of 0.67 µM and a stoichiometry of 2:1 for PtdIns3P binding to Hsv2. PtdIns3P is crucial for the biogenesis of autophagosomes and their precursors. Besides the PROPPINs there are other PtdIns3P binding proteins with a link to autophagy, which includes the FYVE-domain containing proteins ZFYVE1/DFCP1 and WDFY3/ALFY and the PX-domain containing proteins Atg20 and Snx4/Atg24. The methods described could be useful tools for the characterization of these and other phosphoinositide-binding proteins.

  11. Apparatus for characterizing the temporo-spatial properties of a dynamic fluid front and method thereof

    DOEpatents

    Battiste, Richard L.

    2007-12-25

    Methods and apparatus are described for characterizing the temporal-spatial properties of a dynamic fluid front within a mold space while the mold space is being filled with fluid. A method includes providing a mold defining a mold space and having one or more openings into the mold space; heating a plurality of temperature sensors that extend into the mold space; injecting a fluid into the mold space through the openings, the fluid experiencing a dynamic fluid front while filling the mold space with the fluid; and characterizing temporal-spatial properties of the dynamic fluid front by monitoring a temperature of each of the plurality of heated temperature sensors while the mold space is being filled with the fluid. An apparatus includes a mold defining a mold space; one or more openings for introducing a fluid into the mold space and filling the mold space with the fluid, the fluid experiencing a dynamic fluid front while filling the mold space; a plurality of heated temperature sensors extending into the mold space; and a computer coupled to the plurality of heated temperature sensors for characterizing the temporal-spatial properties of the dynamic fluid front.

  12. Apparatus for characterizing the temporo-spatial properties of a dynamic fluid front and method thereof

    DOEpatents

    Battiste, Richard L

    2013-12-31

    Methods and apparatus are described for characterizing the temporal-spatial properties of a dynamic fluid front within a mold space while the mold space is being filled with fluid. A method includes providing a mold defining a mold space and having one or more openings into the mold space; heating a plurality of temperature sensors that extend into the mold space; injecting a fluid into th emold space through the openings, the fluid experiencing a dynamic fluid front while filling the mold space with a fluid; and characterizing temporal-spatial properties of the dynamic fluid front by monitoring a termperature of each of the plurality of heated temperature sensors while the mold space is being filled with the fluid. An apparatus includes a mold defining a mold space; one or more openings for introducing a fluid into th emold space and filling the mold space with the fluid, the fluid experiencing a dynamic fluid front while filling the mold space; a plurality of heated temperature sensors extending into the mold space; and a computer coupled to the plurality of heated temperature sensors for characterizing the temporal-spatial properties of the dynamic fluid front.

  13. Methods for characterizing x-ray detectors for use at the National Ignition Facility.

    PubMed

    Khan, S F; Benedetti, L R; Hargrove, D R; Glenn, S M; Simanovskaia, N; Holder, J P; Barrios, M A; Hahn, D; Nagel, S R; Bell, P M; Bradley, D K

    2012-10-01

    Gated and streaked x-ray detectors generally require corrections in order to counteract instrumental effects in the data. The method of correcting for gain variations in gated cameras fielded at National Ignition Facility (NIF) is described. Four techniques for characterizing the gated x-ray detectors are described. The current principal method of characterizing x-ray instruments is the production of controlled x-ray emission by laser-generated plasmas as a dedicated shot at the NIF. A recently commissioned pulsed x-ray source has the potential to replace the other characterization systems. This x-ray source features a pulsed power source consisting of a Marx generator, capacitor bank that is charged in series and discharged in parallel, producing up to 300 kV. The pulsed x-ray source initially suffered from a large jitter (∼60 ns), but the recent addition of a pulsed laser to trigger the spark gap has reduced the jitter to ∼5 ns. Initial results show that this tool is a promising alternative to the other flat fielding techniques.

  14. Fractal model and Lattice Boltzmann Method for Characterization of Non-Darcy Flow in Rough Fractures

    PubMed Central

    Ju, Yang; Zhang, Qingang; Zheng, Jiangtao; Chang, Chun; Xie, Heping

    2017-01-01

    The irregular morphology of single rock fracture significantly influences subsurface fluid flow and gives rise to a complex and unsteady flow state that typically cannot be appropriately described using simple laws. Yet the fluid flow in rough fractures of underground rock is poorly understood. Here we present a numerical method and experimental measurements to probe the effect of fracture roughness on the properties of fluid flow in fractured rock. We develop a series of fracture models with various degrees of roughness characterized by fractal dimensions that are based on the Weierstrass–Mandelbrot fractal function. The Lattice Boltzmann Method (LBM), a discrete numerical algorithm, is employed for characterizing the complex unsteady non-Darcy flow through the single rough fractures and validated by experimental observations under the same conditions. Comparison indicates that the LBM effectively characterizes the unsteady non-Darcy flow in single rough fractures. Our LBM model predicts experimental measurements of unsteady fluid flow through single rough fractures with great satisfactory, but significant deviation is obtained from the conventional cubic law, showing the superiority of LBM models of single rough fractures. PMID:28145476

  15. Fractal model and Lattice Boltzmann Method for Characterization of Non-Darcy Flow in Rough Fractures.

    PubMed

    Ju, Yang; Zhang, Qingang; Zheng, Jiangtao; Chang, Chun; Xie, Heping

    2017-02-01

    The irregular morphology of single rock fracture significantly influences subsurface fluid flow and gives rise to a complex and unsteady flow state that typically cannot be appropriately described using simple laws. Yet the fluid flow in rough fractures of underground rock is poorly understood. Here we present a numerical method and experimental measurements to probe the effect of fracture roughness on the properties of fluid flow in fractured rock. We develop a series of fracture models with various degrees of roughness characterized by fractal dimensions that are based on the Weierstrass-Mandelbrot fractal function. The Lattice Boltzmann Method (LBM), a discrete numerical algorithm, is employed for characterizing the complex unsteady non-Darcy flow through the single rough fractures and validated by experimental observations under the same conditions. Comparison indicates that the LBM effectively characterizes the unsteady non-Darcy flow in single rough fractures. Our LBM model predicts experimental measurements of unsteady fluid flow through single rough fractures with great satisfactory, but significant deviation is obtained from the conventional cubic law, showing the superiority of LBM models of single rough fractures.

  16. Fractal model and Lattice Boltzmann Method for Characterization of Non-Darcy Flow in Rough Fractures

    NASA Astrophysics Data System (ADS)

    Ju, Yang; Zhang, Qingang; Zheng, Jiangtao; Chang, Chun; Xie, Heping

    2017-02-01

    The irregular morphology of single rock fracture significantly influences subsurface fluid flow and gives rise to a complex and unsteady flow state that typically cannot be appropriately described using simple laws. Yet the fluid flow in rough fractures of underground rock is poorly understood. Here we present a numerical method and experimental measurements to probe the effect of fracture roughness on the properties of fluid flow in fractured rock. We develop a series of fracture models with various degrees of roughness characterized by fractal dimensions that are based on the Weierstrass–Mandelbrot fractal function. The Lattice Boltzmann Method (LBM), a discrete numerical algorithm, is employed for characterizing the complex unsteady non-Darcy flow through the single rough fractures and validated by experimental observations under the same conditions. Comparison indicates that the LBM effectively characterizes the unsteady non-Darcy flow in single rough fractures. Our LBM model predicts experimental measurements of unsteady fluid flow through single rough fractures with great satisfactory, but significant deviation is obtained from the conventional cubic law, showing the superiority of LBM models of single rough fractures.

  17. Capillary Drop Penetration Method to Characterize the Liquid Wetting of Powders.

    PubMed

    Liu, Zhanjie; Wang, Yifan; Muzzio, Fernando J; Callegari, Gerardo; Drazer, German

    2017-01-10

    We present a method to characterize the wettability of powders, based on the penetration dynamics of a sessile drop deposited on a slightly compressed powder bed. First, we show that a direct comparison of the wetting properties of different liquids is possible without having to solve the three-dimensional liquid penetration problem, by considering the appropriate dimensionless variables. We show that the contact area between the sessile drop and the powder bed remains constant during most of the penetration process and demonstrate that as a result, the evolution of the dimensionless penetration volume is given by a universal function of the dimensionless time, with no dimensionless parameters. Then, using a reference liquid that completely wets the powder, it is possible to obtain an effective contact angle for a test liquid of interest, independent of other properties of the powder bed, such as permeability and a characteristic pore size. We apply the proposed method to estimate the contact angle of water with different powder blends, by using silicone oil as the reference liquid. Finally, to highlight the potential of the proposed method to characterize pharmaceutical powders, we consider a blend of lactose, acetaminophen, and a small amount of lubricant (magnesium stearate). The proposed method adequately captures a significant decrease in hydrophilicity that results from exposing the blend to excessive mixing, a well-known effect in the pharmaceutical industry.

  18. Development of a capillary electrophoresis method for the characterization of "palo azul" (Eysenhardtia polystachya).

    PubMed

    Salinas-Hernández, Pastora; López-Bermúdez, Francisco J; Rodríguez-Barrientos, Damaris; Ramírez-Silva, María Teresa; Romero-Romo, Mario A; Morales-Anzures, Fernando; Rojas-Hernández, Alberto

    2008-03-01

    The tree Eysenhardtia polystachya (Ortega) Sarg. has quite a wide popular use within the traditional Mexican medicine as herbal remedy. Popular practices constitute a relevant enough basis to design optimum analytical methods in order to determine basic principles of diverse medicinal plants. This has become one of the essentials needed to characterize such products, for which it is fundamentally important to develop an efficient and reliable separation method. This work presents the results concerning the development and optimization of a novel CE method for the separation of components from water/etanol (1:1) extracts of E. polystachya, using the following conditions, considered the best obtained: phosphate buffer 10 mM, 20 kV voltage, and pH 8.1 at 214 nm and 50 mM, 12.5 kV voltage with pH 8.1 at 426 nm. The optimization takes into account the parameters associated in the resulting electropherograms, such as number of peaks, migration times, and the Deltat(m) of the neighboring peaks. Under optimal conditions the separation intended was attained within 15 and 20 min for 214 and 426 nm, respectively. The characterization method developed was applied to the analysis of diverse extracts of E. polystachya.

  19. Detection and characterization of impact damage in composite panels using multiple ultrasonic methods

    NASA Astrophysics Data System (ADS)

    Williams, Westin B.; Michaels, Thomas E.; Michaels, Jennifer E.

    2015-03-01

    Abrupt impacts to solid laminate composite panels often produce internal damage that is not visible on the impacted surface. It is important that such damage be promptly detected since it can compromise the strength of composite structures. Ultrasonic C-scan imaging has been extensively used to detect and characterize impact damage using both pulse-echo and through-transmission methods. More recently developed guided wave imaging methods, such as sparse array imaging with baseline subtraction and wavefield imaging, have also been used to successfully detect damage in composite panels; however, their performance is generally not comparable to that achieved with bulk wave C-scans. For this study, various force impacts were used to create defect conditions ranging from barely detectable damage to extensive damage that was visible on the impact surface. Guided wave signals were recorded from an attached sparse transducer array before and after the impacts, and panels were scanned using both conventional ultrasonic C-scan methods and acoustic wavefield imaging. For each method, imaging results are presented and compared in terms of their ability to locate and characterize impact damage.

  20. A novel preparation method for drug nanocrystals and characterization by ultrasonic spray-assisted electrostatic adsorption

    PubMed Central

    Gao, Bing; Wang, Jun; Wang, Dunju; Zhu, Ziqiang; Qiao, Zhiqiang; Yang, Guangcheng; Nie, Fude

    2013-01-01

    Purpose The purpose of this study was to develop a novel and continuous method for preparing a nanosized particle of drug crystals and to characterize its properties. Materials and methods A new apparatus was introduced to crystallize nanosized drug crystals of amitriptyline hydrochloride as a model drug. The samples were prepared in the pure state by ultrasonic spray, and elaborated deposition was completed via electrostatic adsorption. Scanning electron microscopy, X-ray powder diffraction, and atomic force microscopy were used to characterize the size of the particles; this was subsequently followed by differential scanning calorimetry. Results and discussion Nanoparticles of drug crystals were successfully prepared. The size of the drug crystals ranged from 20 nm to 400 nm; the particle size of amitriptyline hydrochloride was approximately 71 nm. The particles were spherical and rectangular in shape. Moreover, the melting point of the nanoparticles decreased from 198.2°C to 196.3°C when compared to raw particle crystals. Furthermore, the agglomeration effect was also attenuated as a result of electrostatic repulsion among each particle when absorbed, and depositing on the inner wall of the gathering unit occurred under the electrostatic effect. Conclusion Ultrasonic spray-assisted electrostatic adsorption is a very effective and continuous method to produce drug nanocrystals. This method can be applied to poorly water-soluble drugs, and it can also be a very effective alternative for industrial production. Once the working parameters are given, drug nanocrystals will be produced continuously. PMID:24143097

  1. Characterizing the uncertainty of classification methods and its impact on the performance of crowdsourcing

    NASA Astrophysics Data System (ADS)

    Ribera, Javier; Tahboub, Khalid; Delp, Edward J.

    2015-03-01

    Video surveillance systems are widely deployed for public safety. Real-time monitoring and alerting are some of the key requirements for building an intelligent video surveillance system. Real-life settings introduce many challenges that can impact the performance of real-time video analytics. Video analytics are desired to be resilient to adverse and changing scenarios. In this paper we present various approaches to characterize the uncertainty of a classifier and incorporate crowdsourcing at the times when the method is uncertain about making a particular decision. Incorporating crowdsourcing when a real-time video analytic method is uncertain about making a particular decision is known as online active learning from crowds. We evaluate our proposed approach by testing a method we developed previously for crowd flow estimation. We present three different approaches to characterize the uncertainty of the classifier in the automatic crowd flow estimation method and test them by introducing video quality degradations. Criteria to aggregate crowdsourcing results are also proposed and evaluated. An experimental evaluation is conducted using a publicly available dataset.

  2. X-ray methods for the chemical characterization of atmospheric aerosols

    SciTech Connect

    Jaklevic, J.M.; Thompson, A.C.

    1981-05-01

    The development and use of several x-ray methods for the chemical characterization of atmospherical aerosol particulate samples are described. These methods are based on the emission, absorption, and scattering of x-ray photons with emphasis on the optimization for the non-destructive analysis of dilute specimens. Techniques discussed include photon induced energy dispersive x-ray fluorescence, extended x-ray absorption fine structure spectroscopy using synchrotron radiation and high-rate x-ray powder diffractometry using a position-sensitive gas proportional counter. These x-ray analysis methods were applied to the measurement of the chemical compositions of size-segregated aerosol particulate samples obtained with dichotomous samplers. The advantages of the various methods for use in such measurements are described and results are presented. In many cases, the complementary nature of the analytical information obtained from the various measurements is an important factor in the characterization of the sample. For example, the multiple elemental analyses obtained from x-ray fluorescence can be used as a cross check on the major compounds observed by powder diffraction.

  3. Evaluation of the capacitively coupled resistivity (line antenna) method for the characterization of vadose zone dynamics

    NASA Astrophysics Data System (ADS)

    Niu, Qifei; Wang, Yu-Hsing; Zhao, Kairan

    2014-07-01

    The electrical resistivity survey, traditionally realized by the direct current (DC) resistivity method, has shown great value for characterizing vadose zone dynamics. Compared with the DC resistivity method, the capacitively coupled (CC) resistivity method has a higher ratio of measurement speed to data density, and thus is economically preferred for resistivity surveys that require high data density, e.g., hydrological characterizations. To test the applicability of the CC resistivity method to the study of vadose zone dynamics, we conducted time-lapse resistivity surveys using a commercial CC resistivity (line antenna) system, the OhmMapper, to monitor the water content change in an unsaturated zone due to artificial rainfall infiltration. Special considerations were paid to the inversion of CC resistivity (line antenna) measurements in order to increase the accuracy of inversion results. The derived resistivity of the subsurface clearly captures the water movement in the vadose zone and shows the applicability of the CC resistivity method. The experiment also showed a limitation of the equipment: when the ground surface became extremely conductive, the OhmMapper falsely interpreted the current level. If the wrong current level is identified in the measurement, the measured resistance should be corrected accordingly. The overestimation of the ground resistivity of the CC resistivity method, arising from the decrease in the ground resistivity, was also examined and discussed. Although the measurement bias was found to be negligible in our study, one should still be cautious about it when using the CC resistivity method for similar applications, especially when the measurement is made with a short dipole cable.

  4. Analytical characterization of cyclodextrins: History, official methods and recommended new techniques.

    PubMed

    Szente, Lajos; Szemán, Julianna; Sohajda, Tamás

    2016-10-25

    The main goal of this review is to provide a comprehensive overview on the methods used for analysis of cyclodextrins (CDs) and CD-derivatives. The paper intends to act as a guide for the readers in looking around the classical and modern instrumental analytical methods suitable for identification, characterization and determination of CDs themselves, CDs in finished products or even in biological samples. At present, in the European and United States Pharmacopoeias, the three parent CDs and two synthetic derivatives, namely the (2-hydroxypropyl)-beta-CD and sulfobutylether-beta-CD Na salt are official. Besides these modified CDs, two other derivatives are approved as excipients in human pharmaceutical products: the (2-hydroxypropyl)-gamma-CD and the randomly methylated-beta-CD. Although most of the official analysis methods in the pharmacopoeias have been well used for decades, new aspects of the functional excipient CD characterization suggest a need to revisit compendial methods. Comparison of strengths and weaknesses of current official methods with new improved techniques intends to help analysts to decide on changing traditional analytical methods with improved new ones. This review also deals with the analytical aspects of the first single isomer CD derivative approved as a drug active (Sugammadex/Bridion(®)) as well as analytical considerations of using CDs themselves as active pharmaceutical ingredients. Stability-indicating instrumental methods suitable to adequately follow chemical- and enzymatic degradation of CDs will also be discussed. Challenges in the determination of CDs in different biological matrices will be illustrated on real pharmaco- and toxicokinetic studies of CD-enabled drug formulations.

  5. Characterization of edible film fabricated with channel catfish (Ictalurus punctatus) gelatin extract using selected pretreatment methods.

    PubMed

    Zhang, S; Wang, Y; Herring, J L; Oh, J-H

    2007-11-01

    Farm-raised catfish are important to the economy of the southeastern states in the United States, and catfish processing produces about 55% of by-products for inexpensive sale. Therefore, the utilization of catfish by-products is of great interest to the catfish industry. The objectives of this research were to determine the optimum pretreatment method to extract catfish gelatin for edible film application, and to characterize physical, mechanical, and barrier properties of edible films fabricated with catfish skin gelatin. Catfish skins obtained from a local plant were treated with 6 selected pretreatment methods. The main extraction was performed with deionized water at 50 degrees C after pretreatment. The gelatin yield was calculated and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) was performed to characterize molecular weight (MW) profile. Color, tensile strength (TS), elongation, and water barrier property were determined to characterize the fabricated catfish gelatin films. From the results of gelatin yield, color, SDS-PAGE, as well as mechanical and barrier properties of the film, the pretreatment method with 0.25 M NaOH and 0.09 M acetic acid, followed by extraction at 50 degrees C for 3 h, was determined as the optimum extraction method. The catfish gelatin exhibited higher MW fractions than commercial mammalian gelatin. The catfish gelatin extracts possessed film-forming properties determined by TS, elongation, and water vapor permeability (WVP) comparable to those of commercial mammalian gelatin. The selected formula for catfish gelatin film was determined as 1% gelatin and 20% glycerol, resulting in greatest TS and lowest WVP.

  6. Optogenetic characterization methods overcome key challenges in synthetic and systems biology.

    PubMed

    Olson, Evan J; Tabor, Jeffrey J

    2014-07-01

    Systems biologists aim to understand how organism-level processes, such as differentiation and multicellular development, are encoded in DNA. Conversely, synthetic biologists aim to program systems-level biological processes, such as engineered tissue growth, by writing artificial DNA sequences. To achieve their goals, these groups have adapted a hierarchical electrical engineering framework that can be applied in the forward direction to design complex biological systems or in the reverse direction to analyze evolved networks. Despite much progress, this framework has been limited by an inability to directly and dynamically characterize biological components in the varied contexts of living cells. Recently, two optogenetic methods for programming custom gene expression and protein localization signals have been developed and used to reveal fundamentally new information about biological components that respond to those signals. This basic dynamic characterization approach will be a major enabling technology in synthetic and systems biology.

  7. Systematic method for electrical characterization of random telegraph noise in MOSFETs

    NASA Astrophysics Data System (ADS)

    Marquez, Carlos; Rodriguez, Noel; Gamiz, Francisco; Ohata, Akiko

    2017-02-01

    This work introduces a new protocol which aims to facilitate massive on-wafer characterization of Random Telegraph Noise (RTN) in MOS transistors. The methodology combines the noise spectral density scanning by gate bias assisted with a modified Weighted Time Lag Plot algorithm to identify unequivocally the single-trap RTN signals in optimum bias conditions for their electrical characterization. The strength of the method is demonstrated by its application for monitoring the distribution of traps over the transistors of a SOI wafer. The influence of the back-gate bias on the RTN characteristics of the SOI devices with coupled front- and back-interfaces has revealed unusual characteristics compatible with the carrier emission to the gate metal contact.

  8. Novel electrochemical method for the characterization of the degree of chirality in chiral polyaniline.

    PubMed

    Feng, Zhang; Li, Ma; Yan, Yang; Jihai, Tang; Xiao, Li; Wanglin, Li

    2013-01-01

    A novel method to indicate the degree of chirality in polyaniline (PANI) was developed. The (D-camphorsulfonic acid)- and (HCl)-PANI-based electrodes exhibited significantly different electrochemical performances in D- and L-Alanine (Ala) aqueous solution, respectively, which can be used for the characterization the optical activity of chiral PANI. Cyclic voltammogram, tafel, and open circuit potential of PANI-based electrodes were measured within D- and L-Ala electrolyte solution, respectively. The open circuit potentials under different reacting conditions were analyzed by Doblhofer model formula, in which [C(+)](poly1)/[C(+)](poly2) was used as a parameter to characterize the degree of chirality in chiral PANI. The results showed that [C(+)](poly1)/[C(+)](poly2) can be increased with increasing concentrations of (1S)-(+)- and (1R)-(-)-10-camphorsulfonic acid. In addition, we detected that appropriate response time and lower temperature are necessary to improve the degree of chirality.

  9. New Method for Characterizing the State of Optical and Opto-Mechanical Systems

    NASA Technical Reports Server (NTRS)

    Keski-Kuha, Ritva; Saif, Babak; Feinberg, Lee; Chaney, David; Bluth, Marcel; Greenfield, Perry; Hack, Warren; Smith, Scott; Sanders, James

    2014-01-01

    James Webb Space Telescope Optical Telescope Element (OTE) is a three mirror anastigmat consisting of a 6.5 m primary mirror (PM), secondary mirror (SM) and a tertiary mirror. The primary mirror is made out of 18 segments. The telescope and instruments will be assembled at Goddard Space Flight Center (GSFC) to make it the Optical Telescope Element-Integrated Science Instrument Module (OTIS). The OTIS will go through environmental testing at GSFC before being transported to Johnson Space Center for testing at cryogenic temperature. The objective of the primary mirror Center of Curvature test (CoC) is to characterize the PM before and after the environmental testing for workmanship. This paper discusses the CoC test including both a surface figure test and a new method for characterizing the state of the primary mirror using high speed dynamics interferometry.

  10. Characterizing night vision goggle noise using the method of paired comparisons

    NASA Astrophysics Data System (ADS)

    Reis, George A.; Marasco, Peter L.; Havig, Paul R.; Heft, Eric L.; Goodyear, Charles D.

    2005-05-01

    Users of night vision goggles (NVGs) have reported differences in NVG noise across different as well as the same type of NVG. To better understand these differences, we attempted to characterize NVG noise by having subjects choose parameters in an NVG simulation to best match the noise in real NVGs. From our previous efforts, we observed interdependence of simulation parameters and variability across observers. This has lead us to use the method of paired comparisons as a process for characterizing NVG noise. The results suggest that people perceive NVG noise differently in terms of spatial, temporal, and contrast combinations. In addition, we provide a methodology for determining psychophysically the best parameter combinations in a simulation"s algorithm to match the real environment that the simulation represents.

  11. Characterization of Material Response During Arc-Jet Testing with Optical Methods Status and Perspectives

    NASA Technical Reports Server (NTRS)

    Winter, Michael

    2012-01-01

    The characterization of ablation and recession of heat shield materials during arc jet testing is an important step towards understanding the governing processes during these tests and therefore for a successful extrapolation of ground test data to flight. The behavior of ablative heat shield materials in a ground-based arc jet facility is usually monitored through measurement of temperature distributions (across the surface and in-depth), and through measurement of the final surface recession. These measurements are then used to calibrate/validate materials thermal response codes, which have mathematical models with reasonably good fidelity to the physics and chemistry of ablation, and codes thus calibrated are used for predicting material behavior in flight environments. However, these thermal measurements only indirectly characterize the pyrolysis processes within an ablative material pyrolysis is the main effect during ablation. Quantification of pyrolysis chemistry would therefore provide more definitive and useful data for validation of the material response codes. Information of the chemical products of ablation, to various levels of detail, can be obtained using optical methods. Suitable optical methods to measure the shape and composition of these layers (with emphasis on the blowing layer) during arc jet testing are: 1) optical emission spectroscopy (OES) 2) filtered imaging 3) laser induced fluorescence (LIF) and 4) absorption spectroscopy. Several attempts have been made to optically measure the material response of ablative materials during arc-jet testing. Most recently, NH and OH have been identified in the boundary layer of a PICA ablator. These species are suitable candidates for a detection through PLIF which would enable a spatially-resolved characterization of the blowing layer in terms of both its shape and composition. The recent emission spectroscopy data will be presented and future experiments for a qualitative and quantitative

  12. How many routes lead to migration? Comparison of methods to assess and characterize migratory movements.

    PubMed

    Cagnacci, Francesca; Focardi, Stefano; Ghisla, Anne; van Moorter, Bram; Merrill, Evelyn H; Gurarie, Eliezer; Heurich, Marco; Mysterud, Atle; Linnell, John; Panzacchi, Manuela; May, Roel; Nygård, Torgeir; Rolandsen, Christer; Hebblewhite, Mark

    2016-01-01

    Decreasing rate of migration in several species as a consequence of climate change and anthropic pressure, together with increasing evidence of space-use strategies intermediate between residency and complete migration, are very strong motivations to evaluate migration occurrence and features in animal populations. The main goal of this paper was to perform a relative comparison between methods for identifying and characterizing migration at the individual and population level on the basis of animal location data. We classified 104 yearly individual trajectories from five populations of three deer species as migratory or non-migratory, by means of three methods: seasonal home range overlap, spatio-temporal separation of seasonal clusters and the Net Squared Displacement (NSD) method. For migratory cases, we also measured timing and distance of migration and residence time on the summer range. Finally, we compared the classification in migration cases across methods and populations. All methods consistently identified migration at the population level, that is, they coherently distinguished between complete or almost complete migratory populations and partially migratory populations. However, in the latter case, methods coherently classified only about 50% of the single cases, that is they classified differently at the individual-animal level. We therefore infer that the comparison of methods may help point to 'less-stereotyped' cases in the residency-to-migration continuum. For cases consistently classified by all methods, no significant differences were found in migration distance, or residence time on summer ranges. Timing of migration estimated by NSD was earlier than by the other two methods, both for spring and autumn migrations. We suggest three steps to identify improper inferences from migration data and to enhance understanding of intermediate space-use strategies. We recommend (i) classifying migration behaviours using more than one method, (ii

  13. A centrifugation-based physicochemical characterization method for the interaction between proteins and nanoparticles

    NASA Astrophysics Data System (ADS)

    Bekdemir, Ahmet; Stellacci, Francesco

    2016-10-01

    Nanomedicine requires in-depth knowledge of nanoparticle-protein interactions. These interactions are studied with methods limited to large or fluorescently labelled nanoparticles as they rely on scattering or fluorescence-correlation signals. Here, we have developed a method based on analytical ultracentrifugation (AUC) as an absorbance-based, label-free tool to determine dissociation constants (KD), stoichiometry (Nmax), and Hill coefficient (n), for the association of bovine serum albumin (BSA) with gold nanoparticles. Absorption at 520 nm in AUC renders the measurements insensitive to unbound and aggregated proteins. Measurements remain accurate and do not become more challenging for small (sub-10 nm) nanoparticles. In AUC, frictional ratio analysis allows for the qualitative assessment of the shape of the analyte. Data suggests that small-nanoparticles/protein complexes significantly deviate from a spherical shape even at maximum coverage. We believe that this method could become one of the established approaches for the characterization of the interaction of (small) nanoparticles with proteins.

  14. Flowing gas in mass spectrometer: method for characterization and impact on ion processing.

    PubMed

    Zhou, Xiaoyu; Ouyang, Zheng

    2014-10-21

    Mass spectrometers are complex instrumentation systems where ions are transferred though different pressure regions and mass-analyzed under high vacuum. In this work, we have investigated the impact of the gas flows that exit almost universally in all pressure regions. We developed a method that incorporates the dynamic gas field with the electric field in the simulation of ion trajectories. The scope of the electro-hydrodynamic simulation (EHS) method was demonstrated for characterizing the ion optical systems at atmospheric pressure interfaces. With experimental validation, the trapping of the externally injected ions in a linear ion trap at low pressure was also studied. Further development of the EHS method and the knowledge acquired in this research are expected to be useful in the design of hybrid instruments and the study of ion energetics.

  15. A new method to characterize the complex mineralogy of ultimate wastes

    SciTech Connect

    Forestier, L. Le; Brown, W.L.; Libourel, G. |

    1995-12-31

    Ultimate wastes, resulting from the incineration of municipal solid wastes, contain high amounts of toxic elements that require stabilization before storage. However, whatever the stabilization processed involved, characterization of their crystal chemistry is essential. In this paper, the authors present a method which allows the determination of the mineralogy of ultimate wastes in detail. They present here an example of results from an ultimate waste, resulting from electrofiltration of fumes. This method is based on grain size and density separations coupled with X-ray diffraction, ICP-ES, ICP-MS, wet chemical methods and electron microprobe analyses. Despite the complexity of this waste, they show that it is possible, not only to determine its mineralogy, but also to give the modal proportions of each phase, and to provide some insights into the crystal chemistry of the main pollutants of this ultimate waste product.

  16. Characterization of reservoir rocks and fluids by surface electromagnetic transient methods

    SciTech Connect

    Hoekstra, P.; Blohm, M.W.; Stoyer, C.H.; James, B.A.

    1992-07-17

    The objectives of this research were to improve the interpretations of transient electromagnetic (TEM) measurements over two-dimensional subsurface structures. TEM is a surface electromagnetic method employed in fossil energy reservoir exploration and characterization. Electrical measurements find application in (i) assisting in fossil energy exploration mainly in areas where seismic methods yield inadequate data quality, such as volcanic covered terrain, permafrost areas, and the Rocky Mountain Overthrust; (ii) mapping contacts between hydrocarbon and brines in shallow producing horizon, and (iii) in monitoring enhanced oil recovery processes which cause zones of lower resistivity. The work under this contract consisted of three tasks: (1) Selection of a test site and acquisition of a high density, 3-component data set over the test site; (2) development of finite element modeling algorithms for computing 3-D EM fields over 2-D EM fields over 2-D subsurface structures; and development of TEM 2-D subsurface imaging method. Accomplishments for this period are described.

  17. Methods for characterizing subsurface volatile contaminants using in-situ sensors

    DOEpatents

    Ho, Clifford K.

    2006-02-21

    An inverse analysis method for characterizing diffusion of vapor from an underground source of volatile contaminant using data taken by an in-situ sensor. The method uses one-dimensional solutions to the diffusion equation in Cartesian, cylindrical, or spherical coordinates for isotropic and homogenous media. If the effective vapor diffusion coefficient is known, then the distance from the source to the in-situ sensor can be estimated by comparing the shape of the predicted time-dependent vapor concentration response curve to the measured response curve. Alternatively, if the source distance is known, then the effective vapor diffusion coefficient can be estimated using the same inverse analysis method. A triangulation technique can be used with multiple sensors to locate the source in two or three dimensions. The in-situ sensor can contain one or more chemiresistor elements housed in a waterproof enclosure with a gas permeable membrane.

  18. Models and methods to characterize site amplification from a pair of records

    USGS Publications Warehouse

    Safak, E.

    1997-01-01

    The paper presents a tutorial review of the models and methods that are used to characterize site amplification from the pairs of rock- and soil-site records, and introduces some new techniques with better theoretical foundations. The models and methods discussed include spectral and cross-spectral ratios, spectral ratios for downhole records, response spectral ratios, constant amplification factors, parametric models, physical models, and time-varying filters. An extensive analytical and numerical error analysis of spectral and cross-spectral ratios shows that probabilistically cross-spectral ratios give more reliable estimates of site amplification. Spectral ratios should not be used to determine site amplification from downhole-surface recording pairs because of the feedback in the downhole sensor. Response spectral ratios are appropriate for low frequencies, but overestimate the amplification at high frequencies. The best method to be used depends on how much precision is required in the estimates.

  19. Advanced digital image analysis method dedicated to the characterization of the morphology of filamentous fungus.

    PubMed

    Hardy, N; Moreaud, M; Guillaume, D; Augier, F; Nienow, A; Béal, C; Ben Chaabane, F

    2017-02-06

    Filamentous fungi have a complex morphology that induces fermentation process development issues, as a consequence of viscosity increase and diffusion limitations. In order to better understand the relationship between viscosity changes and fungus morphology during fermentations of Trichoderma reesei, an accurate image analysis method has been developed to provide quantitative and representative data for morphological analysis. This method consisted of a new algorithm called FACE that allowed sharp images to be created at all positions, segmentation of fungus, and morphological analysis using skeleton and topological approaches. It was applied and validated by characterizing samples of an industrial strain of Trichoderma reesei that had or had not been exposed to an extreme shear stress. This method allowed many morphological characteristics to be identified, among which nine relevant criteria were extracted, regarding the impact of shear stress on the fungus and on the viscosity of the fermentation medium.

  20. Multiscale characterization method for line edge roughness based on redundant second generation wavelet transform

    SciTech Connect

    Wang Fei; Zhao Xuezeng; Li Ning

    2010-10-15

    We introduce a multiscale characterization method for line edge roughness (LER) based on redundant second generation wavelet transform. This method involves decomposing LER characteristics into independent bands with different spatial frequency components at different scales, and analyzing the reconstructed signals to work out the roughness exponent, the spatial frequency distribution characteristics, as well as the rms value. The effect of noise can be predicted using detailed signals in the minimum space of scale. This method was applied to numerical profiles for validation. Results show that according to the line edge profiles with similar amplitudes, the roughness exponent R can effectively reflect the degree of irregularity of LER and intuitively provide information on LER spatial frequency distribution.

  1. Flowing Gas in Mass Spectrometer: Method for Characterization and Impact on Ion Processing

    PubMed Central

    Zhou, Xiaoyu; Ouyang, Zheng

    2014-01-01

    Mass spectrometers are complex instrumentation systems with ions transferred though different pressure regions and mass analyzed at high vacuum. In this work, we have investigated the impacts of the gas flows that exit almost universally in all pressure regions and developed a method incorporating the dynamic gas field with the electric (E) field in the simulation of ion trajectories. The capability of the electro-hydrodynamic simulation (EHS) method was demonstrated for characterizing the ion optical systems in atmospheric pressure interfaces. With experimental validation, the trapping of the externally-injected ions in a linear ion trap at low pressure has also been studied. Further development of the EHS method and the knowledge acquired in this research are expected to be useful in the design of hybrid instruments and study of ion energetics. PMID:25121805

  2. An Evaluation of Fractal Surface Measurement Methods for Characterizing Landscape Complexity from Remote-Sensing Imagery

    NASA Technical Reports Server (NTRS)

    Lam, Nina Siu-Ngan; Qiu, Hong-Lie; Quattrochi, Dale A.; Emerson, Charles W.; Arnold, James E. (Technical Monitor)

    2001-01-01

    The rapid increase in digital data volumes from new and existing sensors necessitates the need for efficient analytical tools for extracting information. We developed an integrated software package called ICAMS (Image Characterization and Modeling System) to provide specialized spatial analytical functions for interpreting remote sensing data. This paper evaluates the three fractal dimension measurement methods: isarithm, variogram, and triangular prism, along with the spatial autocorrelation measurement methods Moran's I and Geary's C, that have been implemented in ICAMS. A modified triangular prism method was proposed and implemented. Results from analyzing 25 simulated surfaces having known fractal dimensions show that both the isarithm and triangular prism methods can accurately measure a range of fractal surfaces. The triangular prism method is most accurate at estimating the fractal dimension of higher spatial complexity, but it is sensitive to contrast stretching. The variogram method is a comparatively poor estimator for all of the surfaces, particularly those with higher fractal dimensions. Similar to the fractal techniques, the spatial autocorrelation techniques are found to be useful to measure complex images but not images with low dimensionality. These fractal measurement methods can be applied directly to unclassified images and could serve as a tool for change detection and data mining.

  3. Using different chemical methods for deposition of copper selenide thin films and comparison of their characterization.

    PubMed

    Güzeldir, Betül; Sağlam, Mustafa

    2015-11-05

    Different chemical methods such as Successive Ionic Layer Adsorption and Reaction (SILAR), spin coating and spray pyrolysis methods were used to deposite of copper selenide thin films on the glass substrates. The films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), energy dispersive X-ray analysis (EDX) spectroscopy and UV-vis spectrophotometry. The XRD and SEM studies showed that all the films exhibit polycrystalline nature and crystallinity of copper selenide thin films prepared with spray pyrolysis greater than spin coating and SILAR methods. From SEM and AFM images, it was observed copper selenide films were uniform on the glass substrates without any visible cracks or pores. The EDX spectra showed that the expected elements exist in the thin films. Optical absorption studies showed that the band gaps of copper selenide thin films were in the range 2.84-2.93 eV depending on different chemical methods. The refractive index (n), optical static and high frequency dielectric constants (ε0, ε∞) values were calculated by using the energy bandgap values for each deposition method. The obtained results from different chemical methods revealed that the spray pyrolysis technique is the best chemical deposition method to fabricate copper selenide thin films. This absolute advantage was lead to play key roles on performance and efficiency electrochromic and photovoltaic devices.

  4. Method and apparatus for off-gas composition sensing

    DOEpatents

    Ottesen, David Keith; Allendorf, Sarah Williams; Hubbard, Gary Lee; Rosenberg, David Ezechiel

    1999-01-01

    An apparatus and method for non-intrusive collection of off-gas data in a steelmaking furnace includes structure and steps for transmitting a laser beam through the off-gas produced by a steelmaking furnace, for controlling the transmitting to repeatedly scan the laser beam through a plurality of wavelengths in its tuning range, and for detecting the laser beam transmitted through the off-gas and converting the detected laser beam to an electrical signal. The electrical signal is processed to determine characteristics of the off-gas that are used to analyze and/or control the steelmaking process.

  5. Single cell PCR from archival stained bone marrow slides: a method for molecular diagnosis and characterization.

    PubMed

    Zanssen, Stefanie

    2004-01-01

    Molecular analysis of isolated single cells is a powerful tool for clarifying issues of cell origin and clonality. Previous reports have described PCR amplifications from total DNA and RNA extracted from archival bone marrow and peripheral blood smears and have also shown the feasibility of amplifications from single cells, microdissected from stained histological sections. In this study, a method is described for performing PCR from morphologically defined single cells isolated from archival May-Gruenwald-Giemsa-stained bone-marrow and blood smears. Using three DNA extraction procedures, the organic lysis showed reproducible high efficiencies of amplifications. With this method, we were able to amplify long range amplicons up to 14.5 kb from mitochondrial DNA as well as PCR products of conventional length. The usability of such products for molecular diagnosis is demonstrated by restriction fragment length polymorphism (RFLP)characterization of a mitochondrial disorder. In conclusion, this method has the power to perform molecular diagnosis and characterization of diseases on the single cell level, and should provide valuable information to aid disease treatment and prognosis of hematological disorders.

  6. Electrostatic force microscopy as a broadly applicable method for characterizing pyroelectric materials

    NASA Astrophysics Data System (ADS)

    Martin-Olmos, Cristina; Stieg, Adam Z.; Gimzewski, James K.

    2012-06-01

    A general method based on the combination of electrostatic force microscopy with thermal cycling of the substrate holder is presented for direct, nanoscale characterization of the pyroelectric effect in a range of materials and sample configurations using commercial atomic force microscope systems. To provide an example of its broad applicability, the technique was applied to the examination of natural tourmaline gemstones. The method was validated using thermal cycles similar to those experienced in ambient conditions, where the induced pyroelectric response produced localized electrostatic surface charges whose magnitude demonstrated a correlation with the iron content and heat dissipation of each gemstone variety. In addition, the surface charge was shown to persist even at thermal equilibrium. This behavior is attributed to constant, stochastic cooling of the gemstone surface through turbulent contact with the surrounding air and indicates a potential utility for energy harvesting in applications including environmental sensors and personal electronics. In contrast to previously reported methods, ours has a capacity to carry out such precise nanoscale measurements with little or no restriction on the sample of interest, and represents a powerful new tool for the characterization of pyroelectric materials and devices.

  7. Integrated Particle Handling Methods for Multiplexed Microbial Identification and Characterization in Sediments and Groundwater

    SciTech Connect

    Darrell P. Chandler; Ann E. Jarrell; Craig S. Criddle

    2004-03-17

    Molecular methods are still relatively ineffectual for monitoring community dynamics during bioremediation, due primarily to the cost, technical difficulty and retrospective nature of the analyses. For nucleic acid analyses to meaningfully contribute to bioremediation efforts they must not only contribute to the fundamental understanding of microbial ecology, but also be formatted in such a manner that infield analysis can be achieved. The objective of this project is therefore to develop an integrated microbial and nucleic acid detection method and prototype system for the characterization and analysis of subsurface sediments, focusing on the molecular detection of metal and sulfate-reducing bacteria and activity in sediments obtained from the Oak Ridge Field Research Center. We are meeting this objective by combining environmental molecular microbiology with renewable surface techniques, microfluidic systems and microparticle analytical chemistry. The fluidic systems are used to evaluate hypotheses on the integrated biochemistry that is necessary to directly detect 16S rRNA from metal-reducing microbial communities on a suspension microarray, without using the polymerase chain reaction (PCR). These investigations include the use of peptide nucleic acid capture and detection probes and 'tunable surface' concepts to increase nucleic acid capture and detection efficiency and/or mitigate interferences due to co-extracted humic acids. The unified microparticle sample preparation method and suspension array is then used to characterize the 16S rRNA metal- and sulfate-reducing microbial community in FRC sediments before and after biostimulation.

  8. Electrostatic force microscopy as a broadly applicable method for characterizing pyroelectric materials.

    PubMed

    Martin-Olmos, Cristina; Stieg, Adam Z; Gimzewski, James K

    2012-06-15

    A general method based on the combination of electrostatic force microscopy with thermal cycling of the substrate holder is presented for direct, nanoscale characterization of the pyroelectric effect in a range of materials and sample configurations using commercial atomic force microscope systems. To provide an example of its broad applicability, the technique was applied to the examination of natural tourmaline gemstones. The method was validated using thermal cycles similar to those experienced in ambient conditions, where the induced pyroelectric response produced localized electrostatic surface charges whose magnitude demonstrated a correlation with the iron content and heat dissipation of each gemstone variety. In addition, the surface charge was shown to persist even at thermal equilibrium. This behavior is attributed to constant, stochastic cooling of the gemstone surface through turbulent contact with the surrounding air and indicates a potential utility for energy harvesting in applications including environmental sensors and personal electronics. In contrast to previously reported methods, ours has a capacity to carry out such precise nanoscale measurements with little or no restriction on the sample of interest, and represents a powerful new tool for the characterization of pyroelectric materials and devices.

  9. Quantitative Methods for Reservoir Characterization and Improved Recovery: Application to Heavy Oil Sands

    SciTech Connect

    Castle, James W.; Molz, Fred W.; Bridges, Robert A.; Dinwiddie, Cynthia L.; Lorinovich, Caitlin J.; Lu, Silong

    2003-02-07

    This project involved application of advanced analytical property-distribution methods conditioned to continuous outcrop control for improved reservoir characterization and simulation. The investigation was performed in collaboration with Chevron Production Company U.S.A. as an industrial partner, and incorporates data from the Temblor Formation in Chevron's West Coalinga Field, California. Improved prediction of interwell reservoir heterogeneity was needed to increase productivity and to reduce recovery cost for California's heavy oil sands, which contained approximately 2.3 billion barrels of remaining reserves in the Temblor Formation and in other formations of the San Joaquin Valley.

  10. Preparation, characterization and photocatalytic properties of Ho doped ZnO nanostructures synthesized by sonochemical method

    NASA Astrophysics Data System (ADS)

    Phuruangrat, Anukorn; Yayapao, Oranuch; Thongtem, Titipun; Thongtem, Somchai

    2014-03-01

    The three-dimensional flowerlike undoped and Ho doped ZnO microstructure was successfully synthesized by a sonochemical method. The morphologies and structures of the phase were characterized by the analyses of XRD, SEM and TEM. The flower-like structure composed of numerous one-dimensional hexagonal nanoprisms ZnO and Ho doped ZnO were revealed as hexagonal crystal structure with exposure (0 0 1) facet. The Ho doped ZnO exhibited a relatively higher photocatalytic activity than the pure ZnO in the degradation of methylene blue under UV light.

  11. Polarization characterization of PZT disks and of embedded PZT plates by thermal wave methods

    SciTech Connect

    Eydam, Agnes Suchaneck, Gunnar Gerlach, Gerald; Esslinger, Sophia; Schönecker, Andreas; Neumeister, Peter

    2014-11-05

    In this work, the thermal wave method was applied to characterize PZT disks and embedded PZT plates with regard to the polarization magnitude and spatial homogeneity. The samples were exposed to periodic heating by means of a laser beam and the pyroelectric response was determined. Thermal relaxation times (single time constants or distributions of time constants) describe the heat losses of the PZT samples to the environment. The resulting pyroelectric current spectrum was fitted to the superposition of thermal relaxation processes. The pyroelectric coefficient gives insight in the polarization distribution. For PZT disks, the polarization distribution in the surface region showed a characteristic decrease towards the electrodes.

  12. Characterization of 3D rapid prototyped polymeric material by ultrasonic methods

    NASA Astrophysics Data System (ADS)

    Livings, Richard; Dayal, Vinay; Barnard, Dan

    2015-03-01

    Rapid prototyped parts are quickly becoming a viable alternative for manufacturers. Although the polymeric material is initially isotropic, the printing process introduces a level of anisotropy. This work characterizes the elastic and acoustic properties of the material, after printing, using ultrasonic methods. The elastic constants and the level of anisotropy are determined by measuring the ultrasonic wave velocities. It is shown that the material possesses less symmetry than the orthotropic material model. The dispersion and attenuation characteristics are also determined to provide a basis for ultrasonic flaw detection.

  13. Space processing of crystalline materials: A study of known methods of electrical characterization of semiconductors

    NASA Technical Reports Server (NTRS)

    Castle, J. G.

    1976-01-01

    A literature survey is presented covering nondestructive methods of electrical characterization of semiconductors. A synopsis of each technique deals with the applicability of the techniques to various device parameters and to potential in-flight use before, during, and after growth experiments on space flights. It is concluded that the very recent surge in the commercial production of large scale integrated circuitry and other semiconductor arrays requiring uniformity on the scale of a few microns, involves nondestructive test procedures which could well be useful to NASA for in-flight use in space processing.

  14. Interferometric apparatus and method for detection and characterization of particles using light scattered therefrom

    DOEpatents

    Johnston, Roger G.

    1988-01-01

    Interferometric apparatus and method for detection and characterization of particles using light scattered therefrom. Differential phase measurements on scattered light from particles are possible using the two-frequency Zeeman effect laser which emits two frequencies of radiation 250 kHz apart. Excellent discrimination and reproducibility for various pure pollen and bacterial samples in suspension have been observed with a single polarization element. Additionally, a 250 kHz beat frequency was recorded from an individual particle traversing the focused output from the laser in a flow cytometer.

  15. Apparatus and method for detection and characterization of particles using light scattered therefrom

    DOEpatents

    Johnston, R.G.

    1987-03-23

    Apparatus and method for detection and characterization of particles using light scattered therefrom. Differential phase measurements on scattered light from particles are possible using the two-frequency Zeeman effect laser which emits two frequencies of radiation 250 kHz apart. Excellent discrimination and reproducibility for various pure pollen and bacterial samples in suspension have been observed with a single polarization element. Additionally, a 250 kHz beat frequency was recorded from an individual particle traversing the focused output from the laser in a flow cytometer. 13 figs.

  16. Porous media characterization by the two-liquid method: effect of dynamic contact angle and inertia.

    PubMed

    Lavi, Becky; Marmur, Abraham; Bachmann, Joerg

    2008-03-04

    The validity of using the Lucas-Washburn (LW) equation for porous media characterization by the two-liquid capillary penetration method was tested numerically and experimentally. A cylindrical capillary of known radius and contact angle was used as a model system for the tests. It was found that using the LW equation (i.e., ignoring inertia and dynamic contact angle effects) may lead to very erroneous assessment of the capillary radius and the equilibrium contact angle, for a relatively wide range of capillary radii and equilibrium contact angles. A correct assessment requires the application of a penetration kinetics equation that considers inertia and the dynamic contact angle.

  17. Optical method for the characterization of laterally-patterned samples in integrated circuits

    DOEpatents

    Maris, Humphrey J.

    2001-01-01

    Disclosed is a method for characterizing a sample having a structure disposed on or within the sample, comprising the steps of applying a first pulse of light to a surface of the sample for creating a propagating strain pulse in the sample, applying a second pulse of light to the surface so that the second pulse of light interacts with the propagating strain pulse in the sample, sensing from a reflection of the second pulse a change in optical response of the sample, and relating a time of occurrence of the change in optical response to at least one dimension of the structure.

  18. Optical method and system for the characterization of laterally-patterned samples in integrated circuits

    DOEpatents

    Maris, Humphrey J.

    2008-03-04

    Disclosed is a method for characterizing a sample having a structure disposed on or within the sample, comprising the steps of applying a first pulse of light to a surface of the sample for creating a propagating strain pulse in the sample, applying a second pulse of light to the surface so that the second pulse of light interacts with the propagating strain pulse in the sample, sensing from a reflection of the second pulse a change in optical response of the sample, and relating a time of occurrence of the change in optical response to at least one dimension of the structure.

  19. Synthesis and Characterization of Strontium Carbonate Nanostructures via Simple Hydrothermal Method

    NASA Astrophysics Data System (ADS)

    Asgari-Fard, Zahra; Sabet, Mohammad; Salavati-Niasari, Masoud

    2016-02-01

    Strontium carbonate (SrCO3) nanostructures were synthesized via simple hydrothermal method by Sr(NO3)2, ethylenediamine and hydrazine as reagents. The products were characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX) and Fourier transform infrared spectroscopy (FT-IR). Different parameter's effects on the product size and morphology were investigated. It was found that reagent concentration, reaction time and temperature play key roles in morphology of the obtained product.

  20. Method for characterizing the upset response of CMOS circuits using alpha-particle sensitive test circuits

    NASA Technical Reports Server (NTRS)

    Buehler, Martin G. (Inventor); Blaes, Brent R. (Inventor); Nixon, Robert H. (Inventor); Soli, George A. (Inventor)

    1995-01-01

    A method for predicting the SEU susceptibility of a standard-cell D-latch using an alpha-particle sensitive SRAM, SPICE critical charge simulation results, and alpha-particle interaction physics. A technique utilizing test structures to quickly and inexpensively characterize the SEU sensitivity of standard cell latches intended for use in a space environment. This bench-level approach utilizes alpha particles to induce upsets in a low LET sensitive 4-k bit test SRAM. This SRAM consists of cells that employ an offset voltage to adjust their upset sensitivity and an enlarged sensitive drain junction to enhance the cell's upset rate.

  1. Synthesis and characterization of nanophase zirconia : reverse micelle method and neutron scattering study.

    SciTech Connect

    Li, X.

    1998-11-23

    Zirconia is an important transition-metal oxide for catalytic applications. It has been widely used in automotive exhaust treatment, methanol synthesis, isomerization, alkylation, etc. [1]. Nanophase materials have unique physiochemical properties such as quantum size effects, high surface area, uniform morphology, narrow size distribution, and improvement of sintering rates[2]. Microemulsion method provides the means for controlling the microenvironment under which specific chemical reactions may occur in favoring the formation of homogeneous, nanometer-size particles. In this paper, we report the synthesis of nanophase zirconia and the characterization of the microemulsions as well as the powders by small- and wide-angle neutron scattering techniques.

  2. Methods to identify and characterize developmental neurotoxicity for human health risk assessment. I: behavioral effects.

    PubMed Central

    Cory-Slechta, D A; Crofton, K M; Foran, J A; Ross, J F; Sheets, L P; Weiss, B; Mileson, B

    2001-01-01

    Alterations in nervous system function after exposure to a developmental neurotoxicant may be identified and characterized using neurobehavioral methods. A number of methods can evaluate alterations in sensory, motor, and cognitive functions in laboratory animals exposed to toxicants during nervous system development. Fundamental issues underlying proper use and interpretation of these methods include a) consideration of the scientific goal in experimental design, b) selection of an appropriate animal model, c) expertise of the investigator, d) adequate statistical analysis, and e) proper data interpretation. Strengths and weaknesses of the assessment methods include sensitivity, selectivity, practicality, and variability. Research could improve current behavioral methods by providing a better understanding of the relationship between alterations in motor function and changes in the underlying structure of these systems. Research is also needed to develop simple and sensitive assays for use in screening assessments of sensory and cognitive function. Assessment methods are being developed to examine other nervous system functions, including social behavior, autonomic processes, and biologic rhythms. Social behaviors are modified by many classes of developmental neurotoxicants and hormonally active compounds that may act either through neuroendocrine mechanisms or by directly influencing brain morphology or neurochemistry. Autonomic and thermoregulatory functions have been the province of physiologists and neurobiologists rather than toxicologists, but this may change as developmental neurotoxicology progresses and toxicologists apply techniques developed by other disciplines to examine changes in function after toxicant exposure. PMID:11250808

  3. Simulation and characterization of stress in FinFETs using novel LKMC and nanobeam diffraction methods

    NASA Astrophysics Data System (ADS)

    Yiluan, Guo; Guilei, Wang; Chao, Zhao; Jun, Luo

    2015-08-01

    A new simulation method and test instrument has been adopted to verify the traditional stress simulation in FinFET. First, a new algorithm named lattice kinetic Monte Carlo (LKMC) is used to simulate the SiGe epitaxy in source/drain regions and the stress distribution is consequently extracted after the LKMC simulation. Systematic comparison between the traditional polyhedron method and the LKMC method is carried out. The results confirm that extracted stress from both methods is consistent, which verifies the validity of traditional polyhedron method for the purpose of simulating stress in FinFET. In the following experiment, p-type FinFETs with SiGe stressors in source/drain regions are fabricated. The nano beam diffraction (NBD) method is employed to characterize the strain in Si fin. The strain value from the NBD test agrees well with the value extracted from traditional polyhedron simulation. Project supported by the “National S&T Major Project 02”, the Opening Project of Microelectronics Devices & Bulk Si FinFET Integrated Technology, Institute of Microelectronics, Chinese Academy of Sciences (No. 2013ZX02303007-001).

  4. Experimental methods for the characterization of the frequency-dependent viscoelastic properties of soft materials

    PubMed Central

    Kazemirad, Siavash; K. Heris, Hossein; Mongeau, Luc

    2013-01-01

    A characterization method based on Rayleigh wave propagation was developed for the quantification of the frequency-dependent viscoelastic properties of soft materials at high frequencies; i.e., up to 4 kHz. Planar harmonic surface waves were produced on the surface of silicone rubber samples. The phase and amplitude of the propagating waves were measured at different locations along the propagation direction, which allowed the calculation of the complex Rayleigh wavenumbers at each excitation frequency using a transfer function method. An inverse wave propagation problem was then solved to obtain the complex shear/elastic moduli from the measured wavenumbers. In a separate, related investigation, dynamic indentation tests using atomic force microscopy (AFM) were performed at frequencies up to 300 Hz. No systematic verification study is available for the AFM-based method, which can be used when the dimensions of the test samples are too small for other existing testing methods. The results obtained from the Rayleigh wave propagation and AFM-based indentation methods were compared with those from a well-established method, which involves the generation of standing longitudinal compression waves in rod-shaped test specimens. The results were cross validated and qualitatively confirmed theoretical expectations presented in the literature for the frequency-dependence of polymers. PMID:23654420

  5. Application of optical methods to characterize textile materials and their influence on the human skin

    NASA Astrophysics Data System (ADS)

    Strese, Helene; Kuck, Monika; Benken, Rainer; Schanzer, Sabine; Richter, Heike; Fluhr, Joachim W.; Meinke, Martina C.; Benderoth, Christian; Frankowski, Gottfried; Sterry, Wolfram; Lademann, Juergen

    2011-04-01

    The skin is not only the largest organ of the human body, but it is also a barrier to the environment. The major part of the human skin is in constant contact with textile materials. The objective of this study was to characterize textile materials and to investigate their influence on the skin properties. For this purpose, two different textile materials (polyamide and polyester) were objectively characterized by optical coherence tomography and surface structure 3D-profilometry. In addition, subjective textile properties like haptic sensation and stiffness, as tactile characteristics felt by volunteers, were analyzed. The objective textile characteristics and subjective parameters were compared to the barrier properties measured by in vivo laser scanning microscopy . Comparable results were achieved between barrier properties and subjective assessment in relation to the textile characteristics in favor of the polyester fabric. Consequently, the optical method used in dermatology for the analysis of the skin can be applied to characterize and evaluate textile fabrics and their interaction with human skin in vivo.

  6. Microstructural Characterization of Aluminum-Carbon Nanotube Nanocomposites Produced Using Different Dispersion Methods.

    PubMed

    Simões, Sónia; Viana, Filomena; Reis, Marcos A L; Vieira, Manuel F

    2016-06-01

    This research focuses on characterization of the impact of dispersion methods on aluminum-carbon nanotubes (Al-CNTs) nanocomposite structure. Nanocomposites were produced by a conventional powder metallurgy process after the dispersion of the CNTs on the Al powders, using two approaches: (1) the dispersion of CNTs and mixture with Al powders were performed in a single step by ultrasonication; and (2) the CNTs were previously untangled by ultrasonication and then mixed with Al powders by ball milling. Microstructural characterization of Al-CNT nanocomposites was performed by optical microscopy, scanning and transmission electron microscopy, electron backscatter diffraction, and high-resolution transmission electron microscopy (HRTEM). Microstructural characterization revealed that the use of ball milling for mixing CNTs with Al powders promoted the formation of CNT clusters of reduced size, more uniformly dispersed in the matrix, and a nanocomposite of smaller grain size. However, the results of HRTEM and Raman spectroscopy show that ball milling causes higher damage to the CNT structure. The strengthening effect of the CNT is attested by the increase in hardness and tensile strength of the nanocomposites.

  7. Characterization of Y2BaCuO5 nanoparticles synthesized by nano-emulsion method

    NASA Astrophysics Data System (ADS)

    Li, Fang; Vipulanandan, Cumaraswamy

    2007-10-01

    Nanoscale yttrium-barium-copper oxide (Y2BaCuO5, Y211) particles were synthesized using the emulsion method and the solution method. The basic water-in-oil (w/o) emulsion system consisted of n-octane (continuous oil phase), cetyltrimethylammonium bromide (cationic surfactant), butanol (cosurfactant) and water. The composition of the emulsion system was varied and characterized by measuring the conductivity of the solutions and droplet size. The droplet size of emulsion was determined by using the dynamic light scattering method. The water content, cosurfactant content, and surfactant/ n-octane ratio affected the droplet size which was in the range of 3-8 nm, and hence the w/o emulsion system was referred to as a nano-emulsion system. A model was used to verify the droplet size. The influence of salt (Y2(NO3)3) content on the droplet size was investigated and the addition of salt reduced the droplet size. The effects of reaction time and temperature on the Y211 particle sizes were also investigated. The particles were characterized using the TEM, SEM, and XRD. Nanoparticles produced by the nano-emulsion method were calcined at 850°C to form the Y211 phase as compared to solid state processing temperature of 1050°C. Based on the TEM analysis, the average diameter of the Y211 particles produced using the nano-emulsion method was in the range of 30-100 nm. The effect of adding 15% Y211 nanoparticles to the superconductor YBCO-123 as flux pinning centers, was investigated, and the transition temperature was reduced by 3 K.

  8. Error baseline rates of five sample preparation methods used to characterize RNA virus populations

    PubMed Central

    Kugelman, Jeffrey R.; Wiley, Michael R.; Nagle, Elyse R.; Reyes, Daniel; Pfeffer, Brad P.; Kuhn, Jens H.; Sanchez-Lockhart, Mariano; Palacios, Gustavo F.

    2017-01-01

    Individual RNA viruses typically occur as populations of genomes that differ slightly from each other due to mutations introduced by the error-prone viral polymerase. Understanding the variability of RNA virus genome populations is critical for understanding virus evolution because individual mutant genomes may gain evolutionary selective advantages and give rise to dominant subpopulations, possibly even leading to the emergence of viruses resistant to medical countermeasures. Reverse transcription of virus genome populations followed by next-generation sequencing is the only available method to characterize variation for RNA viruses. However, both steps may lead to the introduction of artificial mutations, thereby skewing the data. To better understand how such errors are introduced during sample preparation, we determined and compared error baseline rates of five different sample preparation methods by analyzing in vitro transcribed Ebola virus RNA from an artificial plasmid-based system. These methods included: shotgun sequencing from plasmid DNA or in vitro transcribed RNA as a basic “no amplification” method, amplicon sequencing from the plasmid DNA or in vitro transcribed RNA as a “targeted” amplification method, sequence-independent single-primer amplification (SISPA) as a “random” amplification method, rolling circle reverse transcription sequencing (CirSeq) as an advanced “no amplification” method, and Illumina TruSeq RNA Access as a “targeted” enrichment method. The measured error frequencies indicate that RNA Access offers the best tradeoff between sensitivity and sample preparation error (1.4−5) of all compared methods. PMID:28182717

  9. Characterizing wave propagation to improve indoor step-level person localization using floor vibration

    NASA Astrophysics Data System (ADS)

    Mirshekari, Mostafa; Pan, Shijia; Zhang, Pei; Noh, Hae Young

    2016-04-01

    The objective of this paper is to characterize frequency-dependent wave propagation of footstep induced floor vibration to improve robustness of vibration-based occupant localization. Occupant localization is an essential part of many smart structure applications (e.g., energy management, patient/customer tracking, etc.). Exist- ing techniques include visual (e.g. cameras and IR sensors), acoustic, RF, and load-based approaches. These approaches have many deployment and operational requirements that limits their adaptation. To overcome these limitations, prior work has utilized footstep-induced vibrations to allow sparse sensor configuration and non-intrusive detection. However, frequency dependent propagation characteristics and low signal-to-noise ratio (SNR) of footstep-induced vibrations change the shape of the signal. Furthermore, estimating the wave propagation velocity for forming the multilateration equations and localizing the footsteps is a challenging task. They, in turn, lead to large errors of localization. In this paper, we present a structural vibration based indoor occupant localization technique using improved time-difference-of-arrival between multiple vibration sensors. In particular we overcome signal distortion by decomposing the signal into frequency components and focusing on high energy components for accurate indoor localization. Such decomposition leverages the frequency-specific propagation characteristics and reduces the effect of low SNR (by choosing the components of highest energy). Furthermore, we develop a velocity calibration method that finds the optimal velocity which minimizes the localization error. We validate our approach through field experiments in a building with human participants. We are able to achieve an average localization error of less than 0.21 meters, which corresponds to a 13X reduction in error when compared to the baseline method using raw data.

  10. Nondestructive Methods to Characterize Rock Mechanical Properties at Low-Temperature: Applications for Asteroid Capture Technologies

    NASA Astrophysics Data System (ADS)

    Savage, Kara A.

    Recent government initiatives and commercial activities have targeted asteroids for in situ material characterization, manipulation, and possible resource extraction. Most of these activities and missions have proposed significant robotic components, given the risks and costs associated with manned missions. To successfully execute these robotic activities, detailed mechanical characteristics of the target space bodies must be known prior to contact, in order to appropriately plan and direct the autonomous robotic protocols. Unfortunately, current estimates of asteroid mechanical properties are based on limited direct information, and significant uncertainty remains specifically concerning internal structures, strengths, and elastic properties of asteroids. One proposed method to elucidate this information is through in situ, nondestructive testing of asteroid material immediately after contact, but prior to any manipulation or resource extraction activities. While numerous nondestructive rock characterization techniques have been widely deployed for terrestrial applications, these methods must be adapted to account for unique properties of asteroid material and environmental conditions of space. For example, asteroid surface temperatures may range from -100°C to 30°C due to diurnal cycling, and these low temperatures are especially noteworthy due to their deleterious influence on non-destructive testing. As a result, this thesis investigates the effect of low temperature on the mechanical characteristics and nondestructive technique responses of rock material. Initially, a novel method to produce low temperature rock samples was developed. Dry ice and methanol cooling baths of specific formulations were used to decrease rock to temperatures ranging from -60°C to 0°C. At these temperatures, shale, chalk, and limestone rock samples were exposed to several nondestructive and conventional mechanical tests, including Schmidt hammer, ultrasonic pulse velocity, point

  11. Application of an ESI-QTOF method for the detailed characterization of GSK-3β inhibitors.

    PubMed

    De Simone, Angela; Fiori, Jessica; Naldi, Marina; D'Urzo, Annalisa; Tumiatti, Vincenzo; Milelli, Andrea; Andrisano, Vincenza

    2017-02-27

    The crucial role of Glycogen Synthase Kinase 3 (GSK-3β) as a pivotal player in Alzheimer's Disease (AD) has recently inspired significant attempts to design and synthesize potent kinase inhibitors. In fact GSK-3β is considered the main kinase which catalyzes the microtubule-associated protein tau hyper-phosphorylation and the neurofibrillary tangles (NFT) in vitro and in vivo, The first classes of GSK-3β inhibitors were classified as ATP-competitive and, therefore, they lack of an efficient degree of selectivity over other kinases. In light of this consideration, many efforts are devoted to characterize new non ATP-competitive GSK-3β inhibitors, endowed with high selectivity. In parallel, there is an urgent need to develop new analytical methodologies for the hit selection (highthroughput screening) and ligand binding characterization in terms of potency, affinity and mechanism of action. The new methodology for GSK-3β enzymatic activity determination can be adopted as a realistic alternative to the currently used radioactive, luminescence and fluorescence detection methods, each showing limitations in terms of safety and interferences. Herein, we propose an alternative and selective electrospray ionization quadrupole time-of-flight (ESI-QTOF) method, based on the direct quantification of phosphorylated substrate muscle glycogen synthase GSM, a peptide resembling the high affinity sequence of natural substrate muscle glycogen synthase 1, for the detailed characterization of GSK-3β inhibitors. The method was validated in terms of accuracy and reproducibility of GSM signal intensity with a relative standard deviation RSD% value of 3.55%; Limit of Detection (LOD): 0.006μM; Lower Limit of Quantification (LLOQ): 0.02μM; linearity r(2) 0.9951. The kinetic constants (KM and vmax) of the GSK-3β catalyzed kinase reaction and the inhibitory potency of known ligands (IC50), were determined. All the obtained results were in agreement with those reported in literature

  12. Development of a method for characterizing changes in coal and mineral surfaces resulting from beneficiation processes

    SciTech Connect

    Slomka, B.J.; Seward, K.J.; Dawson, M.R.; Buttermore, W.H.

    1989-01-01

    A novel method was developed for characterizing changes in coal and mineral surfaces resulting from sonication and other cleaning processes. This method employs a unique flow-cell to permit the dynamic measurement of dye adsorption on coal and mineral particle surfaces. The rates and extents of adsorption of ionic dyes on Illinois No. 6 coal were found to be dependent on mineral content and particle size of ground coal samples. A significant correlation was observed between the adsorbed quantity of dye and the total mineral content of coal. In preliminary experiments with methylene blue dye, clay was found to absorb significantly more of the dye than quartz, pyrite, calcite, or clean coal'' surfaces. By using dyes of differing adsorption selectivity, it is demonstrated that sonication reduces the apparent mineral content on the surface of coal. 9 refs., 7 fig., 3 tabs.

  13. Comparison of nitrate attenuation characterization methods at the Uranium mill tailing site in Monument Valley, Arizona

    NASA Astrophysics Data System (ADS)

    Carroll, Kenneth C.; Jordan, Fiona L.; Glenn, Edward P.; Jody Waugh, W.; Brusseau, Mark L.

    2009-11-01

    SummarySeveral methods for characterizing the occurrence and rate of nitrate attenuation were tested at a field site near Monument Valley, Arizona. Spatial and temporal nitrate concentration data collected from a transect of monitoring wells located along the plume centerline were analyzed to evaluate the overall rates of natural attenuation. The occurrence and rate of denitrification was evaluated through microcosm experiments, nitrogen isotopic fractionation analysis, and solute-transport modeling. First-order denitrification-rate coefficients calculated with each method were comparable. In addition, the composite natural attenuation rate coefficient was similar to the denitrification-rate coefficients, which suggests that microbially induced decay primarily controls nitrate attenuation at the site. This

  14. A Simple Method for MR Gradient System Characterization and k-Space Trajectory Estimation

    PubMed Central

    Addy, Nii Okai; Wu, Holden H.; Nishimura, Dwight G.

    2014-01-01

    Fast imaging trajectories are employed in MRI to speed up the acquisition process, but imperfections in the gradient system create artifacts in the reconstructed images. Artifacts result from the deviation between k-space trajectories achieved on the scanner and their original prescription. Measuring or approximating actual k-space trajectories with predetermined gradient timing delays reduces the artifacts, but are generally based on a specific trajectory and scan orientation. A single linear time-invariant characterization of the gradient system, provides a method to predict k-space trajectories scanned in arbitrary orientations through convolution. This is done effciently, by comparing the the Fourier transforms of the input and measured waveforms of a single high-bandwidth test gradient waveform. This new method is tested for spiral, interleaved echo-planar, and 3D cones imaging, demonstrating its ability to reduce reconstructed image artifacts for various k-space trajectories. PMID:22189904

  15. Investigation of methods for fabricating, characterizing, and transporting cryogenic inertial-confinement-fusion tartets

    SciTech Connect

    Fanning, J.J.; Kim, K.

    1981-01-01

    The objective of this work is to investigate methods for fabricating, characterizing and transporting cryogenic inertial confinement fusion targets on a continuous basis. A microprocessor-based data acquisition system has been built that converts a complete target image to digital data, which are then analyzed by automated software procedures. The low temperatures required to freeze the hydrogen isotopes contained in a target is provided by a cryogenic cold chamber capable of attaining 15 K. A new method for target manipulation and positioning is studied that employs molecular gas beams to levitate a target and an electrostatic quadrupole structure to provide for its lateral containment. Since the electrostatic target-positioning scheme requires that the targets be charged, preliminary investigation has been carried out for a target-charging mechanism based on ion-bombardment.

  16. Characterizing the complex permittivity of high-κ dielectrics using enhanced field method.

    PubMed

    Chao, Hsien-Wen; Wong, Wei-Syuan; Chang, Tsun-Hsu

    2015-11-01

    This paper proposed a method to characterize the complex permittivities of samples based on the enhancement of the electric field strength. The enhanced field method significantly improves the measuring range and accuracy of the samples' electrical properties. Full-wave simulations reveal that the resonant frequency is closely related to the dielectric constant of the sample. In addition, the loss tangent can be determined from the measured quality factor and the just obtained dielectric constant. Materials with low dielectric constant and very low loss tangent are measured for benchmarking and the measured results agree well with previous understanding. Interestingly, materials with extremely high dielectric constants (ε(r) > 50), such as titanium dioxide, calcium titanate, and strontium titanate, differ greatly as expected.

  17. Characterizing the complex permittivity of high-κ dielectrics using enhanced field method

    NASA Astrophysics Data System (ADS)

    Chao, Hsien-Wen; Wong, Wei-Syuan; Chang, Tsun-Hsu

    2015-11-01

    This paper proposed a method to characterize the complex permittivities of samples based on the enhancement of the electric field strength. The enhanced field method significantly improves the measuring range and accuracy of the samples' electrical properties. Full-wave simulations reveal that the resonant frequency is closely related to the dielectric constant of the sample. In addition, the loss tangent can be determined from the measured quality factor and the just obtained dielectric constant. Materials with low dielectric constant and very low loss tangent are measured for benchmarking and the measured results agree well with previous understanding. Interestingly, materials with extremely high dielectric constants (ɛr > 50), such as titanium dioxide, calcium titanate, and strontium titanate, differ greatly as expected.

  18. Characterizing abrupt changes in the stock prices using a wavelet decomposition method

    NASA Astrophysics Data System (ADS)

    Caetano, Marco Antonio Leonel; Yoneyama, Takashi

    2007-09-01

    Abrupt changes in the stock prices, either upwards or downwards, are usually preceded by an oscillatory behavior with frequencies that tend to increase as the moment of transition becomes closer. The wavelet decomposition methods may be useful for analysis of this oscillations with varying frequencies, because they provide simultaneous information on the frequency (scale) and localization in time (translation). However, in order to use the wavelet decomposition, certain requirements have to be satisfied, so that the linear and cyclic trends are eliminated by standard least squares techniques. The coefficients obtained by the wavelet decomposition can be represented in a graphical form. A threshold can then be established to characterize the likelihood of a short-time abrupt change in the stock prices. Actual data from the São Paulo Stock Exchange (Bolsa de Valores de São Paulo) were used in this work to illustrate the proposed method.

  19. Blind inversion method using Lamb waves for the complete elastic property characterization of anisotropic plates.

    PubMed

    Vishnuvardhan, J; Krishnamurthy, C V; Balasubramaniam, Krishnan

    2009-02-01

    A novel blind inversion method using Lamb wave S(0) and A(0) mode velocities is proposed for the complete determination of elastic moduli, material symmetries, as well as principal plane orientations of anisotropic plates. The approach takes advantage of genetic algorithm, introduces the notion of "statistically significant" elastic moduli, and utilizes their sensitivities to velocity data to reconstruct the elastic moduli. The unknown material symmetry and the principal planes are then evaluated using the method proposed by Cowin and Mehrabadi [Q. J. Mech. Appl. Math. 40, 451-476 (1987)]. The blind inversion procedure was verified using simulated ultrasonic velocity data sets on materials with transversely isotropic, orthotropic, and monoclinic symmetries. A modified double ring configuration of the single transmitter and multiple receiver compact array was developed to experimentally validate the blind inversion approach on a quasi-isotropic graphite-epoxy composite plate. This technique finds application in the area of material characterization and structural health monitoring of anisotropic platelike structures.

  20. Characterization and comparison of defects detection limits of three ultrasonic non destructive methods

    NASA Astrophysics Data System (ADS)

    Péronnet, E.; Eyma, F.; Welemane, H.; Pescay, C.

    2010-06-01

    This work deals with the Liquid Resin Infusion (LRI) process developed within the research program “FUSelage COMPosite” of DAHER SOCATA. This manufacturing process enables the realization of complex composite structures or fuselage elements in a single phase (mono-material), which considerably reduce connections and relative difficulties. The concern here is the investigation of non destructive testing (NDT) methods that can be applied to LRI-structures in order to define their capacities for defect detection, and especially their associated critical defect size. In aviation industry, the AITM standards require the ultrasonic testing as NDT for composite materials. Therefore the aim of this work is to characterize and compare three different and complementary ultrasonic techniques on composite specimens. Such analysis allows to define the NDT application field of each method in term of defect detection.

  1. Characterization of pure Ni ultrafine/nanoparticles synthesized by electromagnetic levitational gas condensation method

    SciTech Connect

    Khodaei, Azin Hasannasab, Malihe; Amousoltani, Narges; Kermanpur, Ahmad

    2016-02-15

    Highlights: • Ni ultrafine/nanoparticles were produced using the single-step ELGC method. • Ar and He–20%Ar gas mixtures were used as the condensing gas under 1 atm. • Effects of gas type and flow rate on particle size distribution were investigated. • The nanoparticles showed both high saturation magnetization and low coercivity. - Abstract: In this work, Ni ultrafine/nanoparticles were directly produced using the one-step, relatively large-scale electromagnetic levitational gas condensation method. In this process, Ni vapors ascending from the levitated droplet were condensed by Ar and He–20%Ar gas mixtures under atmospheric pressure. Effects of type and flow rate of the condensing gas on the size, size distribution and crystallinity of Ni particles were investigated. The particles were characterized by scanning electron microscopy, X-ray diffraction and vibrating sample magnetometer (VSM). The process parameters for the synthesis of the crystalline Ni ultrafine/nanoparticles were determined.

  2. Methods for validating the presence of and characterizing proteins deposited onto an array

    SciTech Connect

    Schabacker, Daniel S.

    2010-09-21

    A method of determining if proteins have been transferred from liquid-phase protein fractions to an array comprising staining the array with a total protein stain and imaging the array, optionally comparing the staining with a standard curve generated by staining known amounts of a known protein on the same or a similar array; a method of characterizing proteins transferred from liquid-phase protein fractions to an array including staining the array with a post-translational modification-specific (PTM-specific) stain and imaging the array and, optionally, after staining the array with a PTM-specific stain and imaging the array, washing the array, re-staining the array with a total protein stain, imaging the array, and comparing the imaging with the PTM-specific stain with the imaging with the total protein stain; stained arrays; and images of stained arrays.

  3. Size separation method for absorption characterization in brown carbon: Application to an aged biomass burning sample

    NASA Astrophysics Data System (ADS)

    Di Lorenzo, Robert A.; Young, Cora J.

    2016-01-01

    The majority of brown carbon (BrC) in atmospheric aerosols is derived from biomass burning (BB) and is primarily composed of extremely low volatility organic carbons. We use two chromatographic methods to compare the contribution of large and small light-absorbing BrC components in aged BB aerosols with UV-vis absorbance detection: (1) size exclusion chromatography (SEC) and (2) reverse phase high-performance liquid chromatography. We observe no evidence of small molecule absorbers. Most BrC absorption arises from large molecular weight components (>1000 amu). This suggests that although small molecules may contribute to BrC absorption near the BB source, analyses of aerosol extracts should use methods selective to large molecular weight compounds because these species may be responsible for long-term BrC absorption. Further characterization with electrospray ionization mass spectrometry (MS) coupled to SEC demonstrates an underestimation of the molecular size determined through MS as compared to SEC.

  4. Metal-organic frameworks: structure, properties, methods of synthesis and characterization

    NASA Astrophysics Data System (ADS)

    Butova, V. V.; Soldatov, M. A.; Guda, A. A.; Lomachenko, K. A.; Lamberti, C.

    2016-03-01

    This review deals with key methods of synthesis and characterization of metal-organic frameworks (MOFs). The modular structure affords a wide variety of MOFs with different active metal sites and organic linkers. These compounds represent a new stage of development of porous materials in which the pore size and the active site structure can be modified within wide limits. The set of experimental methods considered in this review is sufficient for studying the short-range and long-range order of the MOF crystal structure, determining the morphology of samples and elucidating the processes that occur at the active metal site in the course of chemical reactions. The interest in metal-organic frameworks results, first of all, from their numerous possible applications, ranging from gas separation and storage to chemical reactions within the pores. The bibliography includes 362 references.

  5. Characterizing the complex permittivity of high-κ dielectrics using enhanced field method

    SciTech Connect

    Chao, Hsien-Wen; Wong, Wei-Syuan; Chang, Tsun-Hsu

    2015-11-15

    This paper proposed a method to characterize the complex permittivities of samples based on the enhancement of the electric field strength. The enhanced field method significantly improves the measuring range and accuracy of the samples’ electrical properties. Full-wave simulations reveal that the resonant frequency is closely related to the dielectric constant of the sample. In addition, the loss tangent can be determined from the measured quality factor and the just obtained dielectric constant. Materials with low dielectric constant and very low loss tangent are measured for benchmarking and the measured results agree well with previous understanding. Interestingly, materials with extremely high dielectric constants (ε{sub r} > 50), such as titanium dioxide, calcium titanate, and strontium titanate, differ greatly as expected.

  6. Alternative method to characterize continuous and discontinuous phase transitions in surface reaction models.

    PubMed

    Fernandes, Henrique A; da Silva, Roberto; Santos, Eder D; Gomes, Paulo F; Arashiro, Everaldo

    2016-08-01

    In this paper we revisited the Ziff-Gulari-Barshad model to study its phase transitions and critical exponents through time-dependent Monte Carlo simulations. We use a method proposed recently to locate the nonequilibrium second-order phase transitions and that has been successfully used in systems with defined Hamiltonians and with absorbing states. This method, which is based on optimization of the coefficient of determination of the order parameter, was able to characterize the continuous phase transition of the model, as well as its upper spinodal point, a pseudocritical point located near the discontinuous phase transition. The static critical exponents β, ν_{∥}, and ν_{⊥}, as well as the dynamic critical exponents θ and z for the continuous transition point, were also estimated and are in excellent agreement with results found in literature.

  7. Synthesis and characterization of SnO2 thin films prepared by dip-coating method

    NASA Astrophysics Data System (ADS)

    Carvalho, D. H. Q.; Schiavon, M. A.; Raposo, M. T.; de Paiva, R.; Alves, J. L. A.; Paniago, Roberto. M.; Speziali, N. L.; Ferlauto, A. S.; Ardisson, J. D.

    The optical, electrical and structural properties of SnOare responsible for a large number of technological 2 applications such as gas sensors, optical-electonic devices, varistors and displays. In this paper, we report the preparation of SnO thin films deposited on glass, quartz and silicon substrates by the technique of sol-gel dip-2coating. The films were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), ellipsometry and Mössbauer spectroscopy. We combine the experimental results with ab initio all-electrons calculations, using the density functional theory within the framework of the full-potential linear augmented plane waves method, in order to extract hyperfine parameters. The results show that the synthesis method is able to produce good quality films and that the theory can be helpful to determine quantities difficult to be measured experimentally.

  8. NMR and computational methods in the structural and dynamic characterization of ligand-receptor interactions.

    PubMed

    Ghitti, Michela; Musco, Giovanna; Spitaleri, Andrea

    2014-01-01

    The recurrent failures in drug discovery campaigns, the asymmetry between the enormous financial investments and the relatively scarce results have fostered the development of strategies based on complementary methods. In this context in recent years the rigid lock-and-key binding concept had to be revisited in favour of a dynamic model of molecular recognition accounting for conformational changes of both the ligand and the receptor. The high level of complexity required by a dynamic description of the processes underlying molecular recognition requires a multidisciplinary investigation approach. In this perspective, the combination of nuclear magnetic resonance spectroscopy with molecular docking, conformational searches along with molecular dynamics simulations has given new insights into the dynamic mechanisms governing ligand receptor interactions, thus giving an enormous contribution to the identification and design of new and effective drugs. Herein a succinct overview on the applications of both NMR and computational methods to the structural and dynamic characterization of ligand-receptor interactions will be presented.

  9. A Flexible Microwave De-Embedding Method for On-Wafer Noise Parameter Characterization of MOSFETs

    NASA Astrophysics Data System (ADS)

    Wang, Yueh-Hua; Cho, Ming-Hsiang; Wu, Lin-Kun

    A flexible noise de-embedding method for on-wafer microwave measurements of silicon MOSFETs is presented in this study. We use the open, short, and thru dummy structures to subtract the parasitic effects from the probe pads and interconnects of a fixtured MOS transistor. The thru standard are used to extract the interconnect parameters for subtracting the interconnect parasitics in gate, drain, and source terminals of the MOSFET. The parasitics of the dangling leg in the source terminal are also modeled and taken into account in the noise de-embedding procedure. The MOS transistors and de-embedding dummy structures were fabricated in a standard CMOS process and characterized up to 20GHz. Compared with the conventional de-embedding methods, the proposed technique is accurate and area-efficient.

  10. Application of an alkylammonium method for characterization of phyllosilicates in CI chondrites

    NASA Technical Reports Server (NTRS)

    Golden, D. C.; Ming, D. W.; Zolensky, M. E.; Yang, S. V.

    1994-01-01

    Many meteorites and interplanetary dust particles (IDP's) with primitive compositions contain significant amounts of phyllosilicates, which are generally interpreted as evidence of protoplanetary aqueous alteration at an early period in the solar system. These meteorites are chondrites of the carbonaceous and ordinary varieties. Characterization of phyllosilicates in these materials is important because of the important physico-chemical information they hold, e.g., from well characterized phyllosilicates, thermodynamic stability relations and hence the conditions of formation of phyllosilicates in the parent body of the meteorite can be predicted. Although we are at a rudimentary level of understanding of the minerals resulting from the aqueous alteration in the early solar nebula, we know that the most common phyllosilicates present in chondritic extraterrestrial materials are serpentines, smectites, chlorites, and micas. The characterization of fine grained minerals in meteorites and IDP's rely heavily on electron beam instruments, especially transmission electron microscopy (TEM). Typically, phyllosilicates are identified by a combination of high resolution imaging of basal spacings, electron diffraction analysis, and chemical analysis. Smectites can be difficult to differentiate from micas because the smectites loose their interlayer water and the interlayers collapse to the same basal spacing as mica in the high vacuum of the TEM. In high-resolution TEM (HRTEM) images, smectite basal spacings vary from 1 nm up to 1.5 nm, while micas show 1 or 2 nm basal spacings. Not only is it difficult to differentiate smectites from micas, but there is no way of identifying different classes of smectites in meteorites and IDP's. To differentiate smectites from micas and also to recognize the charge differences among smectites, an alkylammonium method can be employed because the basal spacings of alkylammonium saturated smectites expand as a function of alkylamine chain

  11. Quantitative impact characterization of aeronautical CFRP materials with non-destructive testing methods

    NASA Astrophysics Data System (ADS)

    Kiefel, Denis; Stoessel, Rainer; Grosse, Christian

    2015-03-01

    In recent years, an increasing number of safety-relevant structures are designed and manufactured from carbon fiber reinforced polymers (CFRP) in order to reduce weight of airplanes by taking the advantage of their specific strength into account. Non-destructive testing (NDT) methods for quantitative defect analysis of damages are liquid- or air-coupled ultrasonic testing (UT), phased array ultrasonic techniques, and active thermography (IR). The advantage of these testing methods is the applicability on large areas. However, their quantitative information is often limited on impact localization and size. In addition to these techniques, Airbus Group Innovations operates a micro x-ray computed tomography (μ-XCT) system, which was developed for CFRP characterization. It is an open system which allows different kinds of acquisition, reconstruction, and data evaluation. One main advantage of this μ-XCT system is its high resolution with 3-dimensional analysis and visualization opportunities, which enables to gain important quantitative information for composite part design and stress analysis. Within this study, different NDT methods will be compared at CFRP samples with specified artificial impact damages. The results can be used to select the most suitable NDT-method for specific application cases. Furthermore, novel evaluation and visualization methods for impact analyzes are developed and will be presented.

  12. Comparison of Different Classification Methods for Analyzing Electronic Nose Data to Characterize Sesame Oils and Blends

    PubMed Central

    Shao, Xiaolong; Li, Hui; Wang, Nan; Zhang, Qiang

    2015-01-01

    An electronic nose (e-nose) was used to characterize sesame oils processed by three different methods (hot-pressed, cold-pressed, and refined), as well as blends of the sesame oils and soybean oil. Seven classification and prediction methods, namely PCA, LDA, PLS, KNN, SVM, LASSO and RF, were used to analyze the e-nose data. The classification accuracy and MAUC were employed to evaluate the performance of these methods. The results indicated that sesame oils processed with different methods resulted in different sensor responses, with cold-pressed sesame oil producing the strongest sensor signals, followed by the hot-pressed sesame oil. The blends of pressed sesame oils with refined sesame oil were more difficult to be distinguished than the blends of pressed sesame oils and refined soybean oil. LDA, KNN, and SVM outperformed the other classification methods in distinguishing sesame oil blends. KNN, LASSO, PLS, and SVM (with linear kernel), and RF models could adequately predict the adulteration level (% of added soybean oil) in the sesame oil blends. Among the prediction models, KNN with k = 1 and 2 yielded the best prediction results. PMID:26506350

  13. Micro-scale methods for characterization of supercritical fluid extraction and fractionation processes. [Trichothecene mycotoxins

    SciTech Connect

    Smith, R.D.; Wright, B.W.; Udseth, H.R.

    1984-11-01

    The development of new supercritical fluid extraction and fractionation processes requires exploration of wide ranges of fluid temperature and pressure. As the fluid phase becomes more complex, conventional methods become inadequate unless augmented by increasingly sophisticated analytical instrumentation. In addition to chemical complexity, analysis is often hindered by characteristics of the analyte which makes supercritical fluid extraction desirable (e.g., thermal lability). Micro-scale methods are described which address these problems while providing the additional benefits of speed, reduced cost, greatly reduced sample and solvent consumption, and safety. Techniques are described in which the fluid phase from micro-scale (0.005 to 5 ml) high pressure cells is sampled and analyzed in either continuous or periodic modes. The methods developed in our laboratory utilize capillary supercritical fluid chromatography and direct fluid injection-mass spectrometry (or their combination), in addition to conventional analytical techniques, for the characterization of complex supercritical fluid mixtures. The application of these methods to various extraction and fractionation processes involving CO/sub 2/ and NH/sub 3/, solubility studies of simple and complex mixtures, and the study of rapid chemical processes in supercritical water is described. New methods for the automated examination of extraction processes using capillary chromatography are also described and their initial application illustrated.

  14. Quantitative impact characterization of aeronautical CFRP materials with non-destructive testing methods

    SciTech Connect

    Kiefel, Denis E-mail: Rainer.Stoessel@airbus.com; Stoessel, Rainer E-mail: Rainer.Stoessel@airbus.com; Grosse, Christian

    2015-03-31

    In recent years, an increasing number of safety-relevant structures are designed and manufactured from carbon fiber reinforced polymers (CFRP) in order to reduce weight of airplanes by taking the advantage of their specific strength into account. Non-destructive testing (NDT) methods for quantitative defect analysis of damages are liquid- or air-coupled ultrasonic testing (UT), phased array ultrasonic techniques, and active thermography (IR). The advantage of these testing methods is the applicability on large areas. However, their quantitative information is often limited on impact localization and size. In addition to these techniques, Airbus Group Innovations operates a micro x-ray computed tomography (μ-XCT) system, which was developed for CFRP characterization. It is an open system which allows different kinds of acquisition, reconstruction, and data evaluation. One main advantage of this μ-XCT system is its high resolution with 3-dimensional analysis and visualization opportunities, which enables to gain important quantitative information for composite part design and stress analysis. Within this study, different NDT methods will be compared at CFRP samples with specified artificial impact damages. The results can be used to select the most suitable NDT-method for specific application cases. Furthermore, novel evaluation and visualization methods for impact analyzes are developed and will be presented.

  15. Characterization of activated sludge exocellular polymers using several cation-associated extraction methods.

    PubMed

    Park, Chul; Novak, John T

    2007-04-01

    Evaluation of prior research and preliminary investigations in our laboratory led to the development of an extraction strategy that can be used to target different cations in activated sludge floc and extract their associated extracellular polymeric substances (EPS). The methods we used were the cation exchange resin (CER) procedure, base extraction, and sulfide addition to extract EPS linked with divalent cations, Al, and Fe, respectively. A comparison of sludge cations before and after CER extraction revealed that most of Ca(2+) and Mg(2+) were removed while Fe and Al remained intact, suggesting that this method is highly selective for Ca(2+) and Mg(2+)-bound EPS. The correlation between sludge Fe and sulfide-extracted EPS was indicative of selectivity of this method for Fe-bound EPS. The base extraction was less specific than the other methods but it was the method releasing the largest amount of Al into the extract, indicating that the method extracted Al-bound EPS. Concomitantly, the composition of extracted EPS and the amino acid composition differed for the three methods, indicating that EPS associated with different metals were not the same. The change in EPS following anaerobic and aerobic digestion was also characterized by the three extraction methods. CER-extracted EPS were reduced after aerobic digestion while they changed little by anaerobic digestion. On the other hand, anaerobic digestion was associated with the decrease in sulfide-extracted EPS. These results suggest that different types of cation-EPS binding mechanisms exist in activated sludge and that each cation-associated EPS fraction imparts unique digestion characteristics to activated sludge.

  16. Revised Methods for Characterizing Stream Habitat in the National Water-Quality Assessment Program

    USGS Publications Warehouse

    Fitzpatrick, Faith A.; Waite, Ian R.; D'Arconte, Patricia J.; Meador, Michael R.; Maupin, Molly A.; Gurtz, Martin E.

    1998-01-01

    Stream habitat is characterized in the U.S. Geological Survey's National Water-Quality Assessment (NAWQA) Program as part of an integrated physical, chemical, and biological assessment of the Nation's water quality. The goal of stream habitat characterization is to relate habitat to other physical, chemical, and biological factors that describe water-quality conditions. To accomplish this goal, environmental settings are described at sites selected for water-quality assessment. In addition, spatial and temporal patterns in habitat are examined at local, regional, and national scales. This habitat protocol contains updated methods for evaluating habitat in NAWQA Study Units. Revisions are based on lessons learned after 6 years of applying the original NAWQA habitat protocol to NAWQA Study Unit ecological surveys. Similar to the original protocol, these revised methods for evaluating stream habitat are based on a spatially hierarchical framework that incorporates habitat data at basin, segment, reach, and microhabitat scales. This framework provides a basis for national consistency in collection techniques while allowing flexibility in habitat assessment within individual Study Units. Procedures are described for collecting habitat data at basin and segment scales; these procedures include use of geographic information system data bases, topographic maps, and aerial photographs. Data collected at the reach scale include channel, bank, and riparian characteristics.

  17. Facile time-of-flight methods for characterizing pulsed superfluid helium droplet beams

    SciTech Connect

    He, Yunteng; Zhang, Jie; Li, Yang; Freund, William M.; Kong, Wei

    2015-08-15

    We present two facile time-of-flight (TOF) methods of detecting superfluid helium droplets and droplets with neutral dopants. Without an electron gun and with only a heated filament and pulsed electrodes, the electron impact ionization TOF mass spectrometer can resolve ionized helium clusters such as He{sub 2}{sup +} and He{sub 4}{sup +}, which are signatures of superfluid helium droplets. Without ionizing any helium atoms, multiphoton non-resonant laser ionization of CCl{sub 4} doped in superfluid helium droplets at 266 nm generates complex cluster ions of dopant fragments with helium atoms, including (He){sub n}C{sup +}, (He){sub n}Cl{sup +}, and (He){sub n}CCl{sup +}. Using both methods, we have characterized our cryogenic pulsed valve—the Even-Lavie valve. We have observed a primary pulse with larger helium droplets traveling at a slower speed and a rebound pulse with smaller droplets at a faster speed. In addition, the pickup efficiency of dopant is higher for the primary pulse when the nozzle temperature is higher than 13 K, and the total time duration of the doped droplet pulse is only on the order of 20 μs. These results stress the importance of fast and easy characterization of the droplet beam for sensitive measurements such as electron diffraction of doped droplets.

  18. Facile time-of-flight methods for characterizing pulsed superfluid helium droplet beams.

    PubMed

    He, Yunteng; Zhang, Jie; Li, Yang; Freund, William M; Kong, Wei

    2015-08-01

    We present two facile time-of-flight (TOF) methods of detecting superfluid helium droplets and droplets with neutral dopants. Without an electron gun and with only a heated filament and pulsed electrodes, the electron impact ionization TOF mass spectrometer can resolve ionized helium clusters such as He2(+) and He4(+), which are signatures of superfluid helium droplets. Without ionizing any helium atoms, multiphoton non-resonant laser ionization of CCl4 doped in superfluid helium droplets at 266 nm generates complex cluster ions of dopant fragments with helium atoms, including (He)(n)C(+), (He)(n)Cl(+), and (He)(n)CCl(+). Using both methods, we have characterized our cryogenic pulsed valve—the Even-Lavie valve. We have observed a primary pulse with larger helium droplets traveling at a slower speed and a rebound pulse with smaller droplets at a faster speed. In addition, the pickup efficiency of dopant is higher for the primary pulse when the nozzle temperature is higher than 13 K, and the total time duration of the doped droplet pulse is only on the order of 20 μs. These results stress the importance of fast and easy characterization of the droplet beam for sensitive measurements such as electron diffraction of doped droplets.

  19. Method for site characterization of anisotropic diffuse illumination of photovoltaic systems

    NASA Astrophysics Data System (ADS)

    Russo, Juan M.; Zhang, Deming; Vorndran, Shelby; Gordon, Michael; Castillo, Jose; Brooks, Adria; Lonij, Vincent; Cronin, Alex; Kostuk, Raymond

    2012-10-01

    In this paper a method to characterize the anisotropy of diffuse illumination incident on photovoltaic systems is presented. PV systems are designed based on standard conditions in which only consider direct and isotropic diffuse illumination. Anisotropic illumination can cause the PV system output to step outside of the design specifications. A baffled multi-detector sensor system is described having a discrete set of azimuthal and declination angle combinations in order to constantly sample the irradiance and the incidence angle of the diffuse illumination in all zenith directions. The sensor was deployed in the Tucson Electric Power Solar Test Yard alongside with commercially available PV systems that are independently monitored. Constant and transient sources of anisotropic diffuse illumination, such as surface reflection and cloud edge effects respectively, are measured and modeled with ray tracing software. Results of the method are described for characterizing diffuse illumination at the TEP Solar Test Yard. Understanding the anisotropic diffuse illumination can potentially allow to more accurately predict PV system or to optimize energy harvesting of systems with non-standard mounting conditions as well as building integrated photovoltaic applications.

  20. Transmission electron microscopy as an orthogonal method to characterize protein aggregates

    PubMed Central

    Sung, Joyce J.; Pardeshi, Neha N.; Mulder, Anke M.; Mulligan, Sean K.; Quispe, Joel; On, Kathy; Carragher, Bridget; Potter, Clinton S.; Carpenter, John F.; Schneemann, Anette

    2015-01-01

    Aggregation of protein-based therapeutics is a challenging problem in the biopharmaceutical industry. Of particular concern are implications for product efficacy and clinical safety due to potentially increased immunogenicity of the aggregates. We used transmission electron microscopy (TEM) to characterize biophysical and morphological features of antibody aggregates formed upon controlled environmental stresses. TEM results were contrasted with results obtained in parallel by independent methods, including size exclusion chromatography, dynamic light scattering, microflow imaging and nanoparticle tracking. For TEM, stressed samples were imaged by negative staining and in the frozen-hydrated state. In both cases, aggregates appeared amorphous but differed in fine structural detail. Specifically, negatively stained aggregates were compact and consisted of smaller globular structures that had a notable three dimensional character. Elements of the native IgG structure were retained, suggesting that the aggregates were not assembled from denatured protein. In contrast, aggregates in frozen-hydrated samples appeared as extended, branched protein networks with large surface area. Using multiple scales of magnification, a wide range of particle sizes was observed and semi-quantitatively characterized. The detailed information provided by TEM extended observations obtained with the independent methods, demonstrating the suitability of TEM as a complementary approach to submicron particle analysis. PMID:25231267

  1. LC-MS/MS method for the characterization of the forced degradation products of Entecavir.

    PubMed

    Ramesh, Thippani; Rao, Pothuraju Nageswara; Rao, Ramisetti Nageswara

    2014-02-01

    A rapid, specific, and reliable isocratic LC-MS/MS method has been developed and validated for the identification and characterization of the stressed degradation products of Entecavir (ETV). ETV, an antiviral drug, was subjected to hydrolysis (acidic, alkaline, and neutral), oxidation, photolysis and thermal stress, as per the international conference on harmonization specified conditions. The drug showed extensive degradation under oxidative and acid hydrolysis stress conditions. However, it was stable to thermal, acidic, neutral, and photolysis stress conditions. A total of five degradation products were observed and the chromatographic separation of the drug and its degradation products were achieved on a Waters Symmetry C18 (250 mm × 4.6 mm, id, 5 μm) column using 20 mM ammonium acetate (pH 3)/acetonitrile (50:50, v/v) as a mobile phase. The degradation products were characterized by LC-MS/MS and its fragmentation pathways were proposed. The LC-MS method was validated with respect to specificity, linearity, accuracy, and precision. No previous reports were found in the literature regarding the degradation behavior of ETV.

  2. Wafer scale imprint uniformity evaluated by LSPR spectroscopy: a high volume characterization method for nanometer scale structures.

    PubMed

    Jeppesen, Claus; Lindstedt, Daniel Nilsson; Vig, Asger Laurberg; Kristensen, Anders; Mortensen, N Asger

    2012-09-28

    We exploit the localized surface-plasmon resonance (LSPR) of terahertz gold gammadion structures for wafer scale critical dimension metrology of nanostructures. The proposed characterization method, LSPR spectroscopy, is based on optical transmission measurements and is benchmarked against numerical simulations of imprinted structures characterized by atomic force microscopy. There is a fair agreement between the two methods and the simulations enable the translation of optical spectra to critical dimensions of the physical structures, a concept known from scatterometry. The results demonstrate the potential of LSPR spectroscopy as an alternative characterization method to scanning electron microscopy, atomic force microscopy and scatterometry.

  3. An adaptive wavelet stochastic collocation method for irregular solutions of stochastic partial differential equations

    SciTech Connect

    Webster, Clayton G; Zhang, Guannan; Gunzburger, Max D

    2012-10-01

    Accurate predictive simulations of complex real world applications require numerical approximations to first, oppose the curse of dimensionality and second, converge quickly in the presence of steep gradients, sharp transitions, bifurcations or finite discontinuities in high-dimensional parameter spaces. In this paper we present a novel multi-dimensional multi-resolution adaptive (MdMrA) sparse grid stochastic collocation method, that utilizes hierarchical multiscale piecewise Riesz basis functions constructed from interpolating wavelets. The basis for our non-intrusive method forms a stable multiscale splitting and thus, optimal adaptation is achieved. Error estimates and numerical examples will used to compare the efficiency of the method with several other techniques.

  4. Treatability Test Report: Characterization of Vadose Zone Carbon Tetrachloride Source Strength Using Tomographic Methods at the 216-Z-9 Site

    SciTech Connect

    Truex, Michael J.; Carroll, Kenneth C.; Rohay, Virginia J.; Mackley, Rob D.; Parker, Kyle R.

    2012-09-28

    A treatability test was conducted in 2011 at the 216-Z-9 Trench to evaluate methods for collecting characterization information that supports refined assessment of SVE performance goals based on impact to groundwater. The characterization information can also provide input to operational strategies for continued SVE operation and decisions regarding closure of the SVE system or transition to other remedies, if necessary.

  5. A Novel Ultrasonic Method for Characterizing Microstructural Gradients in Tubular Structures

    NASA Technical Reports Server (NTRS)

    Roth, Don J.; Carney, Dorothy V.; Baaklini, George Y.; Bodis, James R.; Rauser, Richard W.

    1998-01-01

    Ultrasonic velocity and time-of-flight (TOF) imaging that uses back surface reflections to gage volumetric material quality is highly suited for quantitative characterization of microstructural gradients including those due to pore fraction, density, fiber fraction, and chemical composition variations. However, a weakness of conventional pulse echo ultrasonic velocity and TOF imaging is that the image shows the effects of thickness as well as microstructural variations, unless the part is uniformly thick. This limits this imaging method's usefulness in practical applications. Prior studies have described a pulse echo TOF based ultrasonic imaging method that requires using a single transducer in combination with a reflector plate placed behind samples which, eliminates the effect of thickness variation in the image. In those studies, this method was successful at isolating ultrasonic variations due to material in plate like samples of silicon nitride, metal matrix composite, and polymer matrix composite. In this study, the method is engineered for inspection of more complex shaped structures- those having (hollow) tubular or curved geometry. The experimental inspection technique and results are described as applied to a polymer matrix composite "proof of concept" tube that contains machined patches of various depths and an as manufactured monolithic silicon nitride ceramic tube that might be used in "real world" applications.

  6. Novel synthesis of hafnium oxide nanoparticles by precipitation method and its characterization

    SciTech Connect

    Ramadoss, Ananthakumar; Krishnamoorthy, Karthikeyan; Kim, Sang Jae

    2012-09-15

    Highlights: ► HfO{sub 2} NPs were prepared by precipitation method. ► XRD and Raman analysis revealed the presence of monoclinic phase. ► The average particle size of HfO{sub 2} NPs is 20 nm. ► The method is a simple, low cost and eco-friendly approach. -- Abstract: Hafnium oxide nanoparticles (HfO{sub 2} NPs) have been successfully synthesized by means of a novel precipitation method and were characterized by using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Field emission scanning electron microscopy (FESEM), UV–visible, Fourier transform infrared (FTIR) and laser Raman spectroscopy. The XRD and Raman analysis revealed the presence of pure monoclinic HfO{sub 2} NPs. FESEM image showed that the HfO{sub 2} NPs were of spherical shape with an average particle size of about 20 nm. The optical band gap of the HfO{sub 2} NPs was found to be 6.12 eV. Advantages of this method were simple and low cost of synthesis of HfO{sub 2} NPs includes the small and narrow particle size distribution.

  7. Characterization of acellular dermal matrices (ADMs) prepared by two different methods.

    PubMed

    Walter, R J; Matsuda, T; Reyes, H M; Walter, J M; Hanumadass, M

    1998-03-01

    The efficacy of acellular dermal matrix (ADM) in the treatment of full-thickness skin injuries as a dermal substitute depends on its low antigenicity, capacity for rapid vascularization, and stability as a dermal template. These properties will be determined largely by the final composition of the ADM. We have treated human skin with either Dispase followed by Triton X-100 detergent or NaCl followed by SDS detergent, cryosectioned the resulting ADMs, and then characterized them immunohistochemically. Staining for cell-associated antigens (HLA-ABC, HLA-DR, vimentin, desmin, talin), extracellular matrix components (chondroitin sulfate, fibronectin, laminin, vitronectin, hyaluronic acid), elastin, and collagen type VII was dramatically reduced or absent from ADMs prepared by both methods. However, significant amounts of elastin, keratan sulfate, laminin, and collagen types III and IV were still observed in both ADMs. Both methods of ADM preparation resulted in extensive extraction of both cellular and extracellular components of the skin but retention of the basic dermal architecture. In general, ADM prepared by the NaCl-SDS method retained larger amounts of each antigen than did that prepared by the Dispase-Triton method. This was most evident for laminin and type VII collagen but larger amounts of type IV collagen, fibronectin, desmin, elastin, and HLA-DR were also evident in the NaCl-SDS ADM.

  8. A method for two-dimensional characterization of animal vibrational signals transmitted along plant stems.

    PubMed

    McNett, Gabriel D; Miles, Ronald N; Homentcovschi, Dorel; Cocroft, Reginald B

    2006-12-01

    Conventional approaches to measuring animal vibrational signals on plant stems use a single transducer to measure the amplitude of vibrations. Such an approach, however, will often underestimate the amplitude of bending waves traveling along the stem. This occurs because vibration transducers are maximally sensitive along a single axis, which may not correspond to the major axis of stem motion. Furthermore, stem motion may be more complex than that of a bending wave propagating along a single axis, and such motion cannot be described using a single transducer. Here, we describe a method for characterizing stem motion in two dimensions by processing the signals from two orthogonally positioned transducers. Viewed relative to a cross-sectional plane, a point on the stem surface moves in an ellipse at any one frequency, with the ellipse's major axis corresponding to the maximum amplitude of vibration. The method outlined here measures the ellipse's major and minor axes, and its angle of rotation relative to one of the transducers. We illustrate this method with measurements of stem motion during insect vibrational communication. It is likely the two-dimensional nature of stem motion is relevant to insect vibration perception, making this method a promising avenue for studies of plant-borne transmission.

  9. Review: Some Low-Frequency Electrical Methods for Subsurface Characterization and Monitoring in Hydrogeology

    SciTech Connect

    Revil, Andre; Karaoulis, M.; Johnson, Timothy C.; Kemna, Andreas

    2011-01-01

    Low-frequency geoelectrical methods include mainly self-potential, resistivity, and induced polarization. These methods are commonly used to solve hydrogeological problems in the shallow subsurface and provide complementary information to each other and to in-situ measurements. The self-potential method is a passive measurement of the electrical response associated with the in-situ generation of current mainly due to the flow of pore water in porous media, a salinity gradient, and/or the concentration of redox-active species. It can be used to visualize groundwater flow patterns, to determine permeability, and to detect preferential flow paths. Electrical resistivity is dependent on the water content, the temperature, the salinity of the pore water, and the clay content and mineralogy. Induced polarization characterizes the ability of rocks to store electrical energy in terms of ion accumulations in the pore water. Electrical resistivity, time-domain and frequency-domain induced polarization methods can be used to image the permeability and the distribution of contaminants in the ground.

  10. Review: Some low-frequency electrical methods for subsurface characterization and monitoring in hydrogeology

    SciTech Connect

    Revil, Andre; Karaoulis, M.; Johnson, Timothy C.; Kemna, Andreas

    2012-02-10

    Low-frequency geoelectrical methods include mainly self-potential, resistivity, and induced polarization techniques, which have potential inmany environmental and hydrogeological applications. They provide complementary information to each other and to in-situ measurements. The self-potential method is a passive measurement of the electrical response associated with the in-situ generation of electrical current due to the flow of pore water in porous media, a salinity gradient, and/or the concentration of redoxactive species. Under some conditions, this method can be used to visualize groundwater flow, to determine permeability, and to detect preferential flow paths. Electrical resistivity is dependent on the water content, the temperature, the salinity of the pore water, and the clay content and mineralogy. Time-lapse resistivity can be used to assess the permeability and dispersivity distributions and to monitor contaminant plumes. Induced polarization characterizes the ability of rocks to reversibly store electrical energy. It can be used to image permeability and to monitor chemistry of the pore water-minerals interface. These geophysical methods, reviewed in this paper, should always be used in concert with additional in-situ measurements (e.g. in-situ pumping tests, chemical measurements of the pore water), for instance through joint inversion schemes, which is an area of fertile on-going research.

  11. Layered Yb:YAG ceramics produced by two different methods: processing, characterization and comparison

    NASA Astrophysics Data System (ADS)

    Hostaša, Jan; Esposito, Laura; Biasini, Valentina; Piancastelli, Andreana; Vannini, Matteo; Toci, Guido

    2016-03-01

    The use of Yb:YAG ceramic gain media in solid state lasers has been of growing interest for high repetition rate and high power lasers. Probably the most important advantage of ceramic production technology in comparison with that of single crystals is the flexibility of shaping methods that allow the production of near-net-shape components with a welldefined internal structure. In the case of Yb:YAG with dopant distribution designed accordingly to the pumping and cooling geometry the efficiency of the laser device can be enhanced by mitigating thermal lensing effects. The presented work reports on Yb:YAG transparent ceramics composed of layers with different Yb doping produced by two different shaping methods: dry pressing of spray-dried powders and tape casting, all sintered under high vacuum. The selected geometry of materials was based on numerical simulations. Microstructure of the produced materials was characterized by SEM and EDX with a particular attention to the dopant content across the layers. The optical quality of produced ceramics was characterized and discussed in connection with the microstructure and laser emission results. Output power of nearly 7 W and slope efficiency 58.1 % were obtained in QCW regime from bilayered 0-10 %Yb:YAG. In the case of multilayered materials higher scattering losses were observed. The comparison between the two processing methods highlighted that the tape-cast materials provided higher optical uniformity and the diffusion zone between the single layers with different dopant content was about 150 nm compared to about 250 nm in samples produced by pressing of powders.

  12. Methodologies for the thermomechanical characterization of continuous-fiber ceramic matrix composites: A review of test methods

    SciTech Connect

    Lara-Curzio, E.; Ferber, M.K.; Jenkins, M.G.

    1994-05-01

    Requirements for thermomechanical characterization of ceramic matrix composite materials are reviewed. Feasibility of adapting existent room temperature test methods for polymer and metal matrix composites to test ceramic matrix composites at room and elevated temperatures is investigated.

  13. Integrated Methods for Site Characterization and Conceptual Model Development for a Contaminated Fractured-Bedrock Aquifer

    NASA Astrophysics Data System (ADS)

    Johnson, C. D.; Kastrinos, J. R.; Haeni, F. P.

    2005-12-01

    A multi-disciplined and team-based approach was used to integrate geophysical, hydrologic, and chemical data to characterize lithology, fractures, and hydraulic properties of fractured crystalline bedrock and to determine the nature and extent of ground-water contamination from a landfill and former chemical-waste disposal pits at the University of Connecticut. Detection of volatile organic compounds (VOCs) in domestic bedrock wells in the mid-1980s led to this investigation, in which a team comprised of hydrologists, engineers, geophysicists, geologists, chemists, toxicologists, and community-involvement personnel collected, analyzed, and evaluated data; developed and refined a conceptual model of the ground-water flow and contaminant distribution at the site; and evaluated alternatives and implemented a final remediation plan. The characterization phase began in 1999 and the remediation phase is currently ongoing. An integrated and iterative approach of using multiple methods in phases was important for corroborating the interpretation of individual methods and essential for guiding the design and implementation of additional testing at the site. The use of geophysical data early in the investigation allowed the study team to obtain detailed subsurface information using a minimum of boreholes. Surface geophysical methods were used to target potential discharge of contaminants from the landfill for further investigation. Borehole geophysical methods were used to investigate the anomalies identified by surface geophysical methods, the location and orientation of fractures that intersect and surround each well, the direction and magnitude of ambient flow in the wells, and the transmissive fractures that could provide pathways for contaminant migration. Borehole geophysical and hydraulic data were used to design discrete-zone monitoring systems for the collection of hydraulic head and chemical data and to prevent cross contamination through the boreholes. The results

  14. A novel method for multiparameter physiological phenotype characterization at the single-cell level

    NASA Astrophysics Data System (ADS)

    Kelbauskas, Laimonas; Ashili, Shashanka; Houkal, Jeff; Smith, Dean; Mohammadreza, Aida; Lee, Kristen; Kumar, Ashok; Anis, Yasser; Paulson, Tom; Youngbull, Cody; Tian, Yanqing; Johnson, Roger; Holl, Mark; Meldrum, Deirdre

    2011-02-01

    Non-genetic intercellular heterogeneity has been increasingly recognized as one of the key factors in a variety of core cellular processes including proliferation, stimulus response, carcinogenesis and drug resistance. Many diseases, including cancer, originate in a single or a few cells. Early detection and characterization of these abnormal cells can provide new insights into the pathogenesis and serve as a tool for better disease diagnosis and treatment. We report on a novel technology for multiparameter physiological phenotype characterization at the single-cell level. It is based on real-time measurements of concentrations of several metabolites by means of extracellular optical sensors in microchambers of sub-nL volume containing single cells. In its current configuration, the measurement platform features the capability to detect oxygen consumption rate and pH changes under normoxic and hypoxic conditions at the single-cell level. We have conceived, designed and developed a semi-automated method for single-cell manipulation and loading into microwells utilizing custom, high-precision fluid handling at the nanoliter scale. We present the results of a series of measurements of oxygen consumption rates (OCRs) of single human metaplastic esophageal epithelial cells. In addition, to assess the effects of cell-to-cell interactions, we have measured OCRs of two and three cells placed in a single well. The major advantages of the approach are a) multiplexed characterization of cell phenotype at the single-cell level, b) minimal invasiveness due to the distant positioning of sensors, and c) flexibility in terms of accommodating measurements of other metabolites or biomolecules of interest.

  15. Nondestructive testing and characterization of residual stress field using an ultrasonic method

    NASA Astrophysics Data System (ADS)

    Song, Wentao; Xu, Chunguang; Pan, Qinxue; Song, Jianfeng

    2016-03-01

    To address the difficulty in testing and calibrating the stress gradient in the depth direction of mechanical components, a new technology of nondestructive testing and characterization of the residual stress gradient field by ultrasonic method is proposed based on acoustoelasticity theory. By carrying out theoretical analysis, the sensitivity coefficients of different types of ultrasonic are obtained by taking the low carbon steel(12%C) as a research object. By fixing the interval distance between sending and receiving transducers, the mathematical expressions of the change of stress and the variation of time are established. To design one sending-one receiving and oblique incidence ultrasonic detection probes, according to Snell law, the critically refracted longitudinal wave (LCR wave) is excited at a certain depth of the fixed distance of the tested components. Then, the relationship between the depth of LCR wave detection and the center frequency of the probe in Q235 steel is obtained through experimental study. To detect the stress gradient in the depth direction, a stress gradient LCR wave detection model is established, through which the stress gradient formula is derived by the relationship between center frequency and detecting depth. A C-shaped stress specimen of Q235 steel is designed to conduct stress loading tests, and the stress is measured with the five group probes at different center frequencies. The accuracy of ultrasonic testing is verified by X-ray stress analyzer. The stress value of each specific depth is calculated using the stress gradient formula. Accordingly, the ultrasonic characterization of residual stress field is realized. Characterization results show that the stress gradient distribution is consistent with the simulation in ANSYS. The new technology can be widely applied in the detection of the residual stress gradient field caused by mechanical processing, such as welding and shot peening.

  16. Direct-Push Methods for High-Resolution Characterization of Hydraulic Conductivity (Invited)

    NASA Astrophysics Data System (ADS)

    Butler, J. J.; Dietrich, P.; Knobbe, S.; Bohling, G.; Liu, G.; Reboulet, E. C.

    2009-12-01

    Spatial variations in hydraulic conductivity (K) play a critical role in subsurface transport. A major research challenge has been to develop field methods that allow K information to be obtained at the resolution needed to quantify solute movement in heterogeneous formations, as current state-of-the-practice methods have proven to be of limited effectiveness for this purpose. Direct-push methods have shown much promise for characterizing K in shallow (< 30 m) unconsolidated formations. Over the past decade, methods have progressed from empirical relationships based on parameters from cone penetrometer or electrical conductivity logs to small-diameter pipe variants of the slug test to the new generation of methods that can provide reliable K estimates at a resolution and speed that has not previously been possible. Over the last six years, we have focused on developing and field testing two direct-push tools for high-resolution characterization of K: the direct-push permeameter (DPP) and the direct-push injection logger (DPIL). The DPP is a small-diameter tool with a short cylindrical screen and two pressure transducers set into a direct-push rod. A series of injection tests are performed at a given depth and K is estimated from the test responses. The resulting estimate is a weighted average primarily over the interval between the screen and the farthest transducer. Material outside of that interval has little influence, resulting in significant uncertainty about conditions between test depths. The time required for a test sequence (10-15 minutes in moderate to high-K intervals), coupled with the volumetric averaging of the tool, currently limits DPP resolution to ≈ 0.4 m in most cases. The DPIL consists of a single screened port on a direct-push rod. Water is injected through the screen while the pressure response is monitored behind the screen or at the surface. The injection logging process can be conducted continuously at 0.015-m resolution as the tool is

  17. Characterization of NaTaO3 synthesized by ultrasonic method.

    PubMed

    Vázquez-Cuchillo, O; Manzo-Robledo, A; Zanella, R; Elizondo-Villareal, N; Cruz-López, A

    2013-01-01

    NaTaO(3) perovskite-like materials were synthesized using sodium acetate and tantalum ethoxide as precursors in an ultrasonic bath at room temperature. The pristine sample was thermally treated at 600 °C and characterized using XRD, N(2) physisorption, DRS, SEM and TEM techniques. The structural characterization by X-ray powder diffraction revealed that the crystallization of the NaTaO(3) phase prepared at 600 °C showed agglomerates sizes in the micrometric scale, as confirmed by scanning electron microscopy (SEM). On the other hand, well-defined NaTaO(3) particles in the nanometric scale were determined using TEM. It was found that, for the treated sample, the band gap and BET area was 3.8 eV and 9.5m(2) g(-1), respectively. The annealed perovskite, deposited onto ITO glass, presented an important variation in the open circuit potential transient during UV light irradiation in neutral solution, compared with its counterpart prepared by solid-state method. These intrinsic properties, given by the preparation route, might be appropriate for increase its photocatalytic activity.

  18. Characterization of a method for quantitating food consumption for mutation assays in Drosophila

    SciTech Connect

    Thompson, E.D.; Reeder, B.A.; Bruce, R.D. )

    1991-01-01

    Quantitation of food consumption is necessary when determining mutation responses to multiple chemical exposures in the sex-linked recessive lethal assay in Drosophila. One method proposed for quantitating food consumption by Drosophila is to measure the incorporation of 14C-leucine into the flies during the feeding period. Three sources of variation in the technique of Thompson and Reeder have been identified and characterized. First, the amount of food consumed by individual flies differed by almost 30% in a 24 hr feeding period. Second, the variability from vial to vial (each containing multiple flies) was around 15%. Finally, the amount of food consumed in identical feeding experiments performed over the course of 1 year varied nearly 2-fold. The use of chemical consumption values in place of exposure levels provided a better means of expressing the combined mutagenic response. In addition, the kinetics of food consumption over a 3 day feeding period for exposures to cyclophosphamide which produce lethality were compared to non-lethal exposures. Extensive characterization of lethality induced by exposures to cyclophosphamide demonstrate that the lethality is most likely due to starvation, not chemical toxicity.

  19. Fabrication and characterization of cerium-doped barium titanate inverse opal by sol-gel method

    SciTech Connect

    Jin Yi; Zhu Yihua Yang Xiaoling; Li Chunzhong; Zhou Jinghong

    2007-01-15

    Cerium-doped barium titanate inverted opal was synthesized from barium acetate contained cerous acetate and tetrabutyl titanate in the interstitial spaces of a polystyrene (PS) opal. This procedure involves infiltration of precursors into the interstices of the PS opal template followed by hydrolytic polycondensation of the precursors to amorphous barium titanate and removal of the PS opal by calcination. The morphologies of opal and inverse opal were characterized by scanning electron microscope (SEM). The pores were characterized by mercury intrusion porosimetry (MIP). X-ray photoelectron spectroscopy (XPS) investigation showed the doping structure of cerium, barium and titanium. And powder X-ray diffraction allows one to observe the influence of doping degree on the grain size. The lattice parameters, crystal size and lattice strain were calculated by the Rietveld refinement method. The synthesis of cerium-doped barium titanate inverted opals provides an opportunity to electrically and optically engineer the photonic band structure and the possibility of developing tunable three-dimensional photonic crystal devices. - Graphical abstract: Cerium-doped barium titanate inverted opal was synthesized from barium acetate acid contained cerous acetate and tetrabutyl titanate in the interstitial spaces of a PS opal, which involves infiltration of precursors into the interstices of the PS opal template and removal of the PS opal by calcination.

  20. Thermal characterization and analysis of microliter liquid volumes using the three-omega method

    NASA Astrophysics Data System (ADS)

    Roy-Panzer, Shilpi; Kodama, Takashi; Lingamneni, Srilakshmi; Panzer, Matthew A.; Asheghi, Mehdi; Goodson, Kenneth E.

    2015-02-01

    Thermal phenomena in many biological systems offer an alternative detection opportunity for quantifying relevant sample properties. While there is substantial prior work on thermal characterization methods for fluids, the push in the biology and biomedical research communities towards analysis of reduced sample volumes drives a need to extend and scale these techniques to these volumes of interest, which can be below 100 pl. This work applies the 3ω technique to measure the temperature-dependent thermal conductivity and heat capacity of de-ionized water, silicone oil, and salt buffer solution droplets from 24 to 80 °C. Heater geometries range in length from 200 to 700 μm and in width from 2 to 5 μm to accommodate the size restrictions imposed by small volume droplets. We use these devices to measure droplet volumes of 2 μl and demonstrate the potential to extend this technique down to pl droplet volumes based on an analysis of the thermally probed volume. Sensitivity and uncertainty analyses provide guidance for relevant design variables for characterizing properties of interest by investigating the tradeoffs between measurement frequency regime, device geometry, and substrate material. Experimental results show that we can extract thermal conductivity and heat capacity with these sample volumes to within less than 1% of thermal properties reported in the literature.

  1. A novel image-based quantitative method for the characterization of NETosis

    PubMed Central

    Zhao, Wenpu; Fogg, Darin K.; Kaplan, Mariana J.

    2015-01-01

    NETosis is a newly recognized mechanism of programmed neutrophil death. It is characterized by a stepwise progression of chromatin decondensation, membrane rupture, and release of bactericidal DNA-based structures called neutrophil extracellular traps (NETs). Conventional ‘suicidal’ NETosis has been described in pathogenic models of systemic autoimmune disorders. Recent in vivo studies suggest that a process of ‘vital’ NETosis also exists, in which chromatin is condensed and membrane integrity is preserved. Techniques to assess ‘suicidal’ or ‘vital’ NET formation in a specific, quantitative, rapid and semiautomated way have been lacking, hindering the characterization of this process. Here we have developed a new method to simultaneously assess both ‘suicidal’ and ‘vital’ NETosis, using high-speed multi-spectral imaging coupled to morphometric image analysis, to quantify spontaneous NET formation observed ex-vivo or stimulus-induced NET formation triggered in vitro. Use of imaging flow cytometry allows automated, quantitative and rapid analysis of subcellular morphology and texture, and introduces the potential for further investigation using NETosis as a biomarker in pre-clinical and clinical studies. PMID:26003624

  2. Dispersion measurement as a method of quantifying geologic characterization and defining reservoir heterogeneity. Final report

    SciTech Connect

    Menzie, D.E.

    1995-05-01

    The main objective of this research project is to investigate dispersion as a method of quantifying geological characterization and defining reservoir heterogeneity in order to enhance crude oil recovery. The dispersion of flow of a reservoir rock (dispersion coefficient and dispersivity) was identified as one of the physical properties of a reservoir rock by measuring the mixing of two miscible fluids, one displacing the other in a porous medium. A rock was 100% saturated with a resident fluid and displaced by a miscible fluid of equal viscosity and equal density. Some specific experiments were performed with unequal densities. Produced fluid was analyzed by refractometer, nuclear reaction, electrical conductivity and X-ray scan. Several physical and flow characteristics were measured on the sand rock sample in order to establish correlations with the measured dispersion property. Absolute permeability, effective porosity, relative permeability, capillary pressure, the heterogeneity factor and electrical conductivity were used to better understand the flow system. Linear, transverse, 2-D and 3-D dispersions were measured and used to characterize the rock heterogeneity of the flow system. A new system of measuring dispersion was developed using a gas displacing gas system in a porous medium. An attempt was also made to determine the dispersion property of an actual reservoir from present day well log data on a producing well. 275 refs., 102 figs., 17 tabs.

  3. Synthesis and characterization of mesoporous MgO by template-free hydrothermal method

    SciTech Connect

    Cui, Hongmei; Wu, Xiaofeng; Chen, Yunfa; Boughton, R.I.

    2014-02-01

    Highlights: • A simple synthesis of porous MgO with diameter size from 3 to 10 μm without any templates. • Effect of temperature and time were investigated. • Systematic characterization by TG/DTA, XRD, SEM, TEM, and nitrogen adsorption–desorption isotherm of MgO. • A possible formation and crystal growth mechanism of mesopores MgO is proposed. - Abstract: Mesoporous MgO particles have been synthesized through a novel template-free hydrothermal co-precipitation method using a Mg(NO{sub 3}){sub 2} solution as the magnesium source and NaCO{sub 3} as precipitant. The samples were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and N{sub 2} adsorption–desorption analysis. The results indicate that the MgO samples have a disordered mesoporous structure, a large BET surface area, and a large pore volume. The effect of reaction temperature on the MgO product BET surface area was studied. A possible formation and crystal growth mechanism for mesoporous MgO is proposed.

  4. Characterization of single crystalline CdS nanowires synthesized by solvothermal method.

    PubMed

    Hadia, N M A; García-Granda, Santiago; García, José R

    2014-07-01

    Cadmium sulfide (CdS) nanowires with uniform diameter were prepared by the solvothermal method using ethylenediamine (en) as solvent. The products were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scan electron microscopy (SEM), energy dispersive spectroscopy (EDS) and transmission electron microscopy (TEM). It was found that the products are hexagonal crystals of CdS nanowires with diameter of 28 nm and length up to several micrometres. Selected area electron diffraction (SAED) and high resolution TEM (HRTEM) studies indicate the single-crystalline nature of CdS nanowires with an oriented growth along the c-axis direction. The absorption spectrum of the as-prepared CdS nanowires shows an absorption peak of around 485 nm. These CdS nanowires exhibit bright photoluminescence (PL) with two distinct emission bands at 502 nm and 696 nm.

  5. Preparation and characterization of amorphous manganese sulfide thin films by SILAR method

    SciTech Connect

    Pathan, H.M.; Kale, S.S.; Lokhande, C.D.; Han, Sung-Hwan . E-mail: shhan@hanyang.ac.kr; Joo, Oh-Shim

    2007-08-07

    Manganese sulfide thin films were deposited by a simple and inexpensive successive ionic layer adsorption and reaction (SILAR) method using manganese acetate as a manganese and sodium sulfide as sulfide ion sources, respectively. Manganese sulfide films were characterized for their structural, surface morphological and optical properties by means of X-ray diffraction, scanning electron microscopy, energy dispersive X-ray analysis and optical absorption measurement techniques. The as-deposited film on glass substrate was amorphous. The optical band gap of the film was found to be thickness dependent. As thickness increases optical band gap was found to be increase. The water angle contact was found to be 34{sup o}, suggesting hydrophilic nature of manganese sulfide thin films. The presence of Mn and S in thin film was confirmed by energy dispersive X-ray analysis.

  6. Characterization methods of bone-implant-interfaces of bioresorbable and titanium implants by fracture mechanical means.

    PubMed

    Tschegg, E K; Lindtner, R A; Doblhoff-Dier, V; Stanzl-Tschegg, S E; Holzlechner, G; Castellani, C; Imwinkelried, T; Weinberg, A

    2011-07-01

    Bioresorbable materials for implants have become increasingly researched over the last years. The bone-implant-interfaces of three different implant materials, namely a new bioresorbable magnesium alloy, a new self-reinforced polymer implant and a conventional titanium alloy, were tested using various methods: push-out tests, SEM and EDX analyses as well as surface analyses based on stereoscopic 3D pictures were conducted. The fracture energy is proposed as a very significant reference value for characterizing the mechanical performance of a bone-implant system. By using a video-extensometer system instead of, as is commonly done, tracking the movement of the crosshead in the push-out tests, the accuracy of measurement could be increased.

  7. On the Use of Accelerated Test Methods for Characterization of Advanced Composite Materials

    NASA Technical Reports Server (NTRS)

    Gates, Thomas S.

    2003-01-01

    A rational approach to the problem of accelerated testing for material characterization of advanced polymer matrix composites is discussed. The experimental and analytical methods provided should be viewed as a set of tools useful in the screening of material systems for long-term engineering properties in aerospace applications. Consideration is given to long-term exposure in extreme environments that include elevated temperature, reduced temperature, moisture, oxygen, and mechanical load. Analytical formulations useful for predictive models that are based on the principles of time-based superposition are presented. The need for reproducible mechanisms, indicator properties, and real-time data are outlined as well as the methodologies for determining specific aging mechanisms.

  8. Characterization of Some Methods of Preparation for Bioactive Glass Coating on Implants

    NASA Astrophysics Data System (ADS)

    Ma, Jie; Chen, Chuanzhong; Yao, Liang; Bao, Quanhe

    Since the discovery of Bioglass® by Hench, bioactive glasses have been used in many medical applications, such as drug delivery systems, nonload-bearing implants, and bone cements because of their excellent bioactivity and biocompatibility. However, due to their poor mechanical properties, these glasses cannot be used in load-bearing applications, where the metallic alloys are still main materials. One useful approach to solving the mechanical limitations of bioactive glasses is to apply the glasses as the coating on mechanically tough substrates; it was also recognized early that bioactive glasses could be used as coatings for prosthetic metallic implants. In this paper, the mechanism, characterization, and current status of some methods of preparation for bioactive glass coating on implants are introduced. In the end, to get the homogeneous and compact coating with perfect bonding strength, some ideas of improving the performance of coatings are also presented.

  9. Enumeration and characterization of bacteria in mineral water by improved direct viable count method.

    PubMed

    Guyard, S; Mary, P; Defives, C; Hornez, J P

    1999-05-01

    Fifteen strains from two emergent mineral waters were isolated and tentatively identified with API 20NE and BIOLOG GN systems. These strains were screened for their sensitivities to seven replication-inhibiting antibiotics of the (fluoro)quinolone group (nalidixic and pipemidic acid, flumequine, norfloxacin, ofloxacin, pefloxacin and ciprofloxacin). It was shown that the direct viable count (DVC) procedure could be improved by using certain antibiotic cocktails, which were active against the isolates. Geometric bacterial features were successfully determined with image analysis and adapted software (ICONIX, Perfect Image). Elongations were significant and allowed rapid discrimination of antibiotic inhibited and non-inhibited strains. Particular isolates in a mixed culture were characterized and enumerated after only 14 h exposure with the appropriate antibiotic cocktail. This method can also be applied to other communities, such as mixed cultures in bio-fermentors or in food with known microflora.

  10. Unsaturated fractured rock characterization methods and data sets at the Apache Leap Tuff Site

    SciTech Connect

    Rasmussen, T.C.; Evans, D.D.; Sheets, P.J.; Blanford, J.H.

    1990-08-01

    Performance assessment of high-level nuclear waste containment feasibility requires representative values of parameters as input, including parameter moments, distributional characteristics, and covariance structures between parameters. To meet this need, characterization methods and data sets for interstitial, hydraulic, pneumatic and thermal parameters for a slightly welded fractured tuff at the Apache Leap Tuff Site situated in central Arizona are reported in this document. The data sets include the influence of matric suction on measured parameters. Spatial variability is investigated by sampling along nine boreholes at regular distances. Laboratory parameter estimates for 105 core segments are provided, as well as field estimates centered on the intervals where the core segments were collected. Measurement uncertainty is estimated by repetitively testing control samples. 31 refs., 10 figs., 21 tabs.

  11. Methods for radiation detection and characterization using a multiple detector probe

    DOEpatents

    Akers, Douglas William; Roybal, Lyle Gene

    2014-11-04

    Apparatuses, methods, and systems relating to radiological characterization of environments are disclosed. Multi-detector probes with a plurality of detectors in a common housing may be used to substantially concurrently detect a plurality of different radiation activities and types. Multiple multi-detector probes may be used in a down-hole environment to substantially concurrently detect radioactive activity and contents of a buried waste container. Software may process, analyze, and integrate the data from the different multi-detector probes and the different detector types therein to provide source location and integrated analysis as to the source types and activity in the measured environment. Further, the integrated data may be used to compensate for differential density effects and the effects of radiation shielding materials within the volume being measured.

  12. Characterization Method for 3D Substructure of Nuclear Cell Based on Orthogonal Phase Images

    PubMed Central

    Ji, Ying; Liang, Minjie; Hua, Tingting; Xu, Yuanyuan; Xin, Zhiduo; Wang, Yawei

    2015-01-01

    A set of optical models associated with blood cells are introduced in this paper. All of these models are made up of different parts possessing symmetries. The wrapped phase images as well as the unwrapped ones from two orthogonal directions related to some of these models are obtained by simulation technique. Because the phase mutation occurs on the boundary between nucleus and cytoplasm as well as on the boundary between cytoplasm and environment medium, the equation of inflexion curve is introduced to describe the size, morphology, and substructure of the nuclear cell based on the analysis of the phase features of the model. Furthermore, a mononuclear cell model is discussed as an example to verify this method. The simulation result shows that characterization with inflexion curve based on orthogonal phase images could describe the substructure of the cells availably, which may provide a new way to identify the typical biological cells quickly without scanning. PMID:26355740

  13. Synthesis and Characterization of Polyethylene Glycol Mediated Silver Nanoparticles by the Green Method

    PubMed Central

    Shameli, Kamyar; Ahmad, Mansor Bin; Jazayeri, Seyed Davoud; Sedaghat, Sajjad; Shabanzadeh, Parvaneh; Jahangirian, Hossein; Mahdavi, Mahnaz; Abdollahi, Yadollah

    2012-01-01

    The roles of green chemistry in nanotechnology and nanoscience fields are very significant in the synthesis of diverse nanomaterials. Herein, we report a green chemistry method for synthesized colloidal silver nanoparticles (Ag NPs) in polymeric media. The colloidal Ag NPs were synthesized in an aqueous solution using silver nitrate, polyethylene glycol (PEG), and β-D-glucose as a silver precursor, stabilizer, and reducing agent, respectively. The properties of synthesized colloidal Ag NPs were studied at different reaction times. The ultraviolet-visible spectra were in excellent agreement with the obtained nanostructure studies performed by transmission electron microscopy (TEM) and their size distributions. The Ag NPs were characterized by utilizing X-ray diffraction (XRD), zeta potential measurements and Fourier transform infrared (FT-IR). The use of green chemistry reagents, such as glucose, provides green and economic features to this work. PMID:22837654

  14. Improved SEC-FTIR method for the characterization of multimodal high-density polyethylenes.

    PubMed

    Piel, Christian; Albrecht, Andreas; Neubauer, Corinna; Klampfl, Christian W; Reussner, Jens

    2011-06-01

    A size-exclusion chromatography-Fourier transform infrared spectroscopy (SEC-FTIR) method for the analysis of high-density polyethylene copolymers was developed, providing superior resolution for the determination of short-chain branching as a function of time and improved repeatability by hardware adaptation and processing optimization. SEC-FTIR for characterization of polyolefins is a compromising technique. Best resolution in terms of molecular weight and molecular weight distribution requires a very low sample solution concentration in size-exclusion chromatography while best results from online infrared (IR) spectroscopy require as high concentrations as possible. The signal-to-noise ratio at the IR detector could be increased significantly after application of a bandpass filter instead of a steel mesh attenuator and furthermore influences of system instabilities could be decreased by changes in data processing. Reliable short-chain branching information in the high molecular weight section in respect to accuracy and repeatability with better chromatographic resolution could be achieved.

  15. Preparation and characterization of nanostructured titanate bioceramic coating by anodization-hydrothermal method

    NASA Astrophysics Data System (ADS)

    Liu, Qiannan; Liu, Yong; Lei, Ting; Tan, Yanni; Wu, Hong; Li, Jianbo

    2015-02-01

    In this work, nanostructured titanate coatings were prepared on pure titanium substrate by hydrothermal treatment combined with and without anodic oxidation. The morphology and microstructure of coatings were characterized and the corrosion resistance and bioactivity were studied. The results show that the anodization-hydrothermal method is suitable for the formation of nanostructured titanate coating on Ti in concentrated KOH solution. The coatings are composed of K2Ti6O13 and H2Ti2O5·H2O, and can greatly improve the corrosion resistance of Ti substrate. Moreover, the coatings can induce the formation of new apatite layer after the immersion in simulated body fluid, exhibiting good bioactivity. The anodizaiton treatment can not only accelerate the formation of nanostructures, but also can provide nucleation sites for nanostructured titanates, tailoring the morphology of coating. The titanium substrate with nanostructured titanate coating is expected to have significant applications as biomedical materials.

  16. Gradient plasticity crack tip characterization by means of the extended finite element method

    NASA Astrophysics Data System (ADS)

    Martínez-Pañeda, E.; Natarajan, S.; Bordas, S.

    2017-01-01

    Strain gradient plasticity theories are being widely used for fracture assessment, as they provide a richer description of crack tip fields by incorporating the influence of geometrically necessary dislocations. Characterizing the behavior at the small scales involved in crack tip deformation requires, however, the use of a very refined mesh within microns to the crack. In this work a novel and efficient gradient-enhanced numerical framework is developed by means of the extended finite element method (X-FEM). A mechanism-based gradient plasticity model is employed and the approximation of the displacement field is enriched with the stress singularity of the gradient-dominated solution. Results reveal that the proposed numerical methodology largely outperforms the standard finite element approach. The present work could have important implications on the use of microstructurally-motivated models in large scale applications. The non-linear X-FEM code developed in MATLAB can be downloaded from http://www.empaneda.com/codes.

  17. Characterizing the effects of silver alloying in chalcopyrite CIGS solar cells with junction capacitance methods

    SciTech Connect

    Erslev, Peter T.; Hanket, Gregory M.; Shafarman, William N.; Cohen, J. David

    2009-04-01

    A variety of junction capacitance-based characterization methods were used to investigate alloys of Ag into Cu(In1-xGax)Se2 photovoltaic solar cells over a broad range of compositions. These alloys show encouraging trends of increasing VOC with increasing Ag content, opening the possibility of wide-gap cells for use in tandem device applications. Drive level capacitance profiling (DLCP) has shown very low free carrier concentrations for all Ag-alloyed devices, in some cases less than 1014 cm-3, which is roughly an order of magnitude lower than that of CIGS devices. Transient photocapacitance spectroscopy has revealed very steep Urbach edges, with energies between 10 meV and 20 meV, in the Ag-alloyed samples. This is in general lower than the Urbach edges measured for standard CIGS samples and suggests a significantly lower degree of structural disorder.

  18. The morphological characterizations of titanium dioxide (TiO2) via sol-gel method

    NASA Astrophysics Data System (ADS)

    Nordin, N. K. S.; Hashim, U.; Vijayakumaran, T.

    2017-03-01

    Titanium Dioxide (TiO2) has comes with many fascinating properties in environmental purification, photocatalytic activity and in sensor application. TiO2 is prepared by sol-gel method and been coated on the silicon oxide (SiO) and glasses for 1 layer, 3 layers, 5 layers and finally 7 layers to find the best layer for coating purpose. A few characterizations had been carried out such as Scanning Electron Microscope (SEM), Photoluminescence (PL) and Current-Voltage (I-V) measurement for TiO2. The I-V recorded for the presence of Interdigitated Electrode (IDE) is 2.46×10-10 at 1V increased from 2.24×10-10 without the coating of TiO2. TiO2 coated on IDE triggered more sensitive sensor compared to IDE without metal oxides coated.

  19. Characterization of nano-sized SiC@Ni composite fabricated by electroless plating method.

    PubMed

    Xu, Zhan; Chen, Yigang

    2013-02-01

    A nano-sized SiC@Ni composite was prepared by simple electroless plating method. Nickel can be reduced by Na2H2PO2 under the catalysis of Pd to despite onto the surface of SiC nanoparticles. The composite structure was characterized by means of TEM images, XRD and the components were analyzed using EDS. The coating layer on the SiC particles was several nanometers thick and mainly in a form of fine Ni crystalline grain and amorphous Ni-P alloy. By increasing the concentration of Na2H2PO2 in the plating bath, the uniformity of the coating layer can be improved obviously. Both of the magnetism and crystallinity of Ni coatings depends on the P content in the coating which can be decreased by increasing the pH values of plating solutions. The SiC@Ni particles exhibited soft magnetic characteristics.

  20. Methods and Systems for Characterization of an Anomaly Using Infrared Flash Thermography

    NASA Technical Reports Server (NTRS)

    Koshti, Ajay M. (Inventor)

    2013-01-01

    A method for characterizing an anomaly in a material comprises (a) extracting contrast data; (b) measuring a contrast evolution; (c) filtering the contrast evolution; (d) measuring a peak amplitude of the contrast evolution; (d) determining a diameter and a depth of the anomaly, and (e) repeating the step of determining the diameter and the depth of the anomaly until a change in the estimate of the depth is less than a set value. The step of determining the diameter and the depth of the anomaly comprises estimating the depth using a diameter constant C.sub.D equal to one for the first iteration of determining the diameter and the depth; estimating the diameter; and comparing the estimate of the depth of the anomaly after each iteration of estimating to the prior estimate of the depth to calculate the change in the estimate of the depth of the anomaly.