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1

Passive neutron techniques for the nondestructive assay of nuclear material  

E-print Network

Three drums containing potentially contaminated lead bricks were assayed with the Segmented Gamma Scan Neutron Assay System (SGSNAS) at Pacific Northwest National Laboratory's (PNNL) Nondestructive Assay Center. The assay system reported...

Mapili, Gabriel

2012-06-07

2

Nondestructive assay using active and passive computed tomography  

SciTech Connect

The United States Department of Energy (DOE) has over 600,000 transuranic (TRU) waste drums temporarily stored at nearly 40 sites within the United States. Contents of these drums must be characterized before they are transported for permanent disposal. Traditional gamma-ray methods used to characterize nuclear waste introduce errors that are related to nonuniform measurement responses associated with unknown radioactive source and matrix material distributions. These errors can be reduced by application of tomographic techniques, that measure these distributions. The Lawrence Livermore National Laboratory (LLNL) has developed two tomographic-based waste assay systems. They use external radioactive sources and tomography-protocol to map the attenuation within a waste drum as a function of mono-energetic gamma-ray energy in waste containers. Passive tomography is used to localize and identify specific radioactive waste contents within the same waste containers. Reconstruction of the passive data via the active images allows internal waste radioactivities in a drum to be corrected for any overlying heterogeneous materials, thus yielding an absolute assay of the waste radioactivities. Calibration of both systems requires only point source measurements and are independent of matrix materials. The first system is housed at LLNL and was developed to study and validate research concepts. The second system is being developed with Bioimaging Research, Inc. (BIR) and is housed within a mobile waste characterization trailer. This system has traveled to three DOE facilities to demonstrate the active and passive computed tomography capability. Both systems have participated in and successfully passed the requirements of formal DOE-sponsored intercomparison studies. The systems have measured approximately 1 to 100 grains of plutonium within a variety of waste matrix materials. Laboratory and field results from these two systems over the past several years show that both systems are capable of a precision of 1 to 4% and an accuracy of better than 30% of the true values of known standards for all drums measured.

Roberson, G. P. ,LLNL

1998-07-01

3

Passive Neutron Non-Destructive Assay for Remediation of Radiological Waste at Hanford Burial Grounds- 13189  

SciTech Connect

The Hanford burial grounds contains a broad spectrum of low activity radioactive wastes, transuranic (TRU) wastes, and hazardous wastes including fission products, byproduct material (thorium and uranium), plutonium and laboratory chemicals. A passive neutron non-destructive assay technique has been developed for characterization of shielded concreted drums exhumed from the burial grounds. This method facilitates the separation of low activity radiological waste containers from TRU waste containers exhumed from the burial grounds. Two identical total neutron counting systems have been deployed, each consisting of He-3 detectors surrounded by a polyethylene moderator. The counts are processed through a statistical filter that removes outliers in order to suppress cosmic spallation events and electronic noise. Upon completion of processing, a 'GO / NO GO' signal is provided to the operator based on a threshold level equivalent to 0.5 grams of weapons grade plutonium in the container being evaluated. This approach allows instantaneous decisions to be made on how to proceed with the waste. The counting systems have been set up using initial on-site measurements (neutron emitting standards loaded into surrogate waste containers) combined with Monte Carlo modeling techniques. The benefit of this approach is to allow the systems to extend their measurement ranges, in terms of applicable matrix types and container sizes, with minimal interruption to the operations at the burial grounds. (authors)

Simpson, A.; Pitts, M. [Pajarito Scientific Corporation, 2976 Rodeo Park Drive East, Santa Fe, NM 87505 (United States)] [Pajarito Scientific Corporation, 2976 Rodeo Park Drive East, Santa Fe, NM 87505 (United States); Ludowise, J.D.; Valentinelli, P. [Washington Closure Hanford, 2620 Fermi Ave., Richland, WA 99354 (United States)] [Washington Closure Hanford, 2620 Fermi Ave., Richland, WA 99354 (United States); Grando, C.J. [ELR Consulting, Inc., 15247 Wilbur Rd., La Conner, WA 98257 (United States)] [ELR Consulting, Inc., 15247 Wilbur Rd., La Conner, WA 98257 (United States); Haggard, D.L. [WorleyParsons Polestar, 601 Williams Blvd., Richland, WA 99354 (United States)] [WorleyParsons Polestar, 601 Williams Blvd., Richland, WA 99354 (United States)

2013-07-01

4

Application of gamma-ray active and passive computed tomography to nondestructively assay TRU waste  

SciTech Connect

The authors have developed an active and passive computed tomography scanner for assaying radioactive waste drums. They describe the hardware and software components of the system used for data acquisition, gamma-ray spectroscopy analysis, and image reconstruction. They have measured the performance of the system using mock waste drums and calibrated radioactive sources. They describe the results of measurements using this system to assay a real TRU waste drum with relatively low Pu content.

Martz, H.E.; Decman, D.J.; Roberson, G.P.; Johansson, E.M.; Keto, E.R.

1996-05-01

5

Non-destructive assay of spent nuclear fuel using passive neutron Albedo reactivity  

SciTech Connect

Passive Neutron Albedo Reactivity (PNAR) is one of fourteen techniques that has been researched and evaluated to form part of a comprehensive and integrated detection system for the non-destructive assay (NDA) of spent nuclear fuel. PNAR implemented with {sup 3}He tubes for neutron detection (PNAR-{sup 3}He) is the measurement of time correlated neutrons from a spent fuel assembly with and without a Cadmium (Cd) layer surrounding the assembly. PNAR utilizes the self-interrogation of the fuel via reflection of neutrons born in the fuel assembly back in to the fuel assembly. The neutrons originate primarily from spontaneous fission events within the fuel itself (Curium-244) but are amplified by multiplication. The presence and removal of the Cd provides two measurement conditions with different neutron energy spectra and therefore different interrogating neutron characteristics. Cd has a high cross-section of absorption for slow neutrons and therefore greatly reduces the low energy (thermal) neutron fluence rate returning. The ratios of the Singles, Doubles and Triples count rates obtained in each case are known as the Cd ratios, which are related to fissile content. A potential safeguards application for which PNAR-{sup 3}He is particularly suited is 'fingerprinting'. Fingerprinting could function as an alternative to plutonium (Pu) mass determination; providing confidence that material was not diverted during transport between sites. PNAR-{sup 3}He has six primary NDA signatures: Singles, Doubles and Triples count rates measured with two energy spectra at both shipping and receiving sites. This is to uniquely identify the fuel assembly, and confirm no changes have taken place during transport. Changes may indicate all attempt to divert material for example. Here, the physics of the PNAR-{sup 3}He concept will be explained, alongside a discussion on the development of a prototypical PNAR-{sup 3}He instrument using simulation. The capabilities and performance of the conceptual instrument will be summarized, in the context of (a) quantifying Pu mass in spent fuel assemblies and (b) detecting pin diversion (through a discrepancy between declared and measured properties of the fuel assembly) when the instrument is deployed. These quantitative capabilities are complementary to the 'fingerprinting' capability which is part of ensuring continuity of knowledge and custody of spent nuclear fuel.

Evans, L G [Los Alamos National Laboratory; Schear, M A [Los Alamos National Laboratory; Croft, S [Los Alamos National Laboratory; Tobin, S J [Los Alamos National Laboratory; Swinhoe, M T [Los Alamos National Laboratory; Menlove, H O [Los Alamos National Laboratory

2010-01-01

6

Nondestructive assay of TRU waste using gamma-ray active and passive computed tomography  

SciTech Connect

The authors have developed an active and passive computed tomography (A and PCT) scanner for assaying radioactive waste drums. Here they describe the hardware components of their system and the software used for data acquisition, gamma-ray spectroscopy analysis, and image reconstruction. They have measured the performance of the system using ``mock`` waste drums and calibrated radioactive sources. They also describe the results of measurements using this system to assay a real TRU waste drum with relatively low Pu content. The results are compared with X-ray NDE studies of the same TRU waste drum as well as assay results from segmented gamma scanner (SGS) measurements.

Roberson, G.P.; Decman, D.; Martz, H.; Keto, E.R.; Johansson, E.M.

1995-10-04

7

Expert system technology for nondestructive waste assay  

SciTech Connect

Nondestructive assay waste characterization data generated for use in the National TRU Program must be of known and demonstrable quality. Each measurement is required to receive an independent technical review by a qualified expert. An expert system prototype has been developed to automate waste NDA data review of a passive/active neutron drum counter system. The expert system is designed to yield a confidence rating regarding measurement validity. Expert system rules are derived from data in a process involving data clustering, fuzzy logic, and genetic algorithms. Expert system performance is assessed against confidence assignments elicited from waste NDA domain experts. Performance levels varied for the active, passive shielded, and passive system assay modes of the drum counter system, ranging from 78% to 94% correct classifications.

Becker, G.K.; Determan, J.C.

1998-07-01

8

Nondestructive waste-drum assay for transuranic content by gamma-ray active and passive computed tomography  

Microsoft Academic Search

A gamma-ray-based, active (A) and passive (P) computed tomography (CT) technology has been developed that locates, identifies and quantifies gamma-ray emitting isotopes, transuranic (TRU) and others, in nuclear waste drums. ACT uses a collimated external source and a HPGe detector to measure selected mono-energetic gamma-rays that are attenuated by waste-drum contents; a separate PCT measurement uses the HPGe detector to

D. C Camp; H. E Martz; G. P Roberson; D. J Decman; R. T Bernardi

2002-01-01

9

Nondestructive assay of green HTGR fuel rods  

Microsoft Academic Search

This report describes the nondestructive (NDA) work done at Los Alamos during 1979 and 1980 as part of the New Brunswick Laboratory-sponsored evaluation of NDA of the uranium content of fabricated fuel rods for high-temperature gas-cooled reactors (HTGR). The methods used (delayed neutron and passive gamma ray) are concisely described, and the results are summarized and compared in graphical and

H. H. Barschall; M. M. Meier; J. L. Parker

2010-01-01

10

Preparation of Pure Plutonium Metal Standards for Nondestructive Assay  

SciTech Connect

To calibrate neutron coincidence and neutron multiplicity counters for passive assay of plutonium, certain detector parameters must be determined. When one is using small plutonium metal samples, biases can be introduced from non-zero multiplication and impurities. This paper describes preparing small, pure plutonium metal standards with well-known geometries to enable accurate multiplication corrections and with acceptably low levels of impurities. To minimize multiplication, these standards are designed as 2-cm-diameter foils with varying thicknesses and masses of 1.4, 3.6, and 7.2 g plutonium. These standards will significantly improve characterization and calibration of neutron coincidence and multiplicity counters. They can also be equally useful for gamma-ray spectrometry and calorimetry. Five sets will be made: four for other US Department of Energy plutonium facilities, and one set to remain at Los Alamos. We will also describe other nondestructive assay standards that are planned for the next few years.

S. -T. Hsue; J. E. Stewart; M. S. Krick

2000-11-01

11

Nondestructive techniques for assaying fuel debris in piping at Three Mile Island Unit 2  

SciTech Connect

Four major categories of nondestructive techniques - ultrasonic, passive gamma ray, infrared detection, and remote video examination - have been determined to be feasible for assaying fuel debris in the primary coolant system of the Three Mile Island Unit 2 (TMI-2) Reactor. Passive gamma ray detection is the most suitable technique for the TMI-2 piping; however, further development of this technique is needed for specific application to TMI-2.

Vinjamuri, K.; McIsaac, C.V.; Beller, L.S.; Isaacson, L.; Mandler, J.W.; Hobbins, R.R. Jr.

1981-11-01

12

Comparison of Destructive and Nondestructive Assay of Heterogeneous Salt Residues.  

National Technical Information Service (NTIS)

To study problems associated with nondestructive assay (NDA) measurements of molten salt residues, a joint study was conducted by the Rocky Flats Plant, Golden, CO and Mound Laboratories, Miamisburg, OH. Extensive NDA measurements were made on nine contai...

J. G. Fleissner, M. W. Hume

1986-01-01

13

Mobile nondestructive examination and assay instruments  

SciTech Connect

A compact system that evaluates radioactive materials can furnish a big savings to taxpayers by ensuring that only properly identified nuclear waste is sent to a Department of Energy (DOE) radioactive waste storage area. The Los Alamos National Laboratory's Advanced Nuclear Technology Group has developed and field tested two easily transportable, self-contained modules: one performs real-time radiography of special 208-/l/ shipment containers, the other assays the contents. The examination and assay system is a simple, portable solution to a complex problem that ensures only properly packaged transuranic (TRU) waste is shipped to the Department of Energy's Waste Isolation Pilot Plant (WIPP) near Carlsbad, New Mexico. 3 refs., 6 figs.

Bieri, J.M.; Caldwell, J.T.

1988-01-01

14

Kalman filter analysis of delayed neutron nondestructive assay measurements.  

SciTech Connect

The ability to nondestructively determine the presence and quantity of fissile and fertile nuclei in various matrices is important in several nuclear applications including international and domestics safeguards, radioactive waste characterization and nuclear facility operations. Material irradiation followed by delayed neutron counting is a well known and useful nondestructive assay technique used to determine the fissile-effective content of assay samples. Previous studies have demonstrated the feasibility of using Kalman filters to unfold individual isotopic contributions to delayed neutron measurements resulting from the assay of mixes of uranium and plutonium isotopes. However, the studies in question used simulated measurement data and idealized parameters. We present the results of the Kalman filter analysis of several measurements of U/Pu mixes taken using Argonne National Laboratory's delayed neutron nondestructive assay device. The results demonstrate the use of Kalman filters as a signal processing tool to determine the fissile and fertile isotopic content of an assay sample from the aggregate delayed neutron response following neutron irradiation.

Aumeier, S. E.

1998-04-29

15

Determination of Plutonium Content in Spent Fuel with Nondestructive Assay  

SciTech Connect

There are a variety of reasons for quantifying plutonium (Pu) in spent fuel such as independently verifying the Pu content declared by a regulated facility, making shipper/receiver mass declarations, and quantifying the input mass at a reprocessing facility. As part of the Next Generation Safeguards Initiative, NA-241 has recently funded a multilab/university collaboration to determine the elemental Pu mass in spent fuel assemblies. This research effort is anticipated to be a five year effort: the first part of which is a two years Monte Carlo modeling effort to integrate and down-select among 13 nondestructive assay (NDA) technologies, followed by one year for fabricating instruments and then two years for measuring spent fuel. This paper gives a brief overview of the approach being taken for the Monte Carlo research effort. In addition, preliminary results for the first NDA instrument studied in detail, delayed neutron detection, will be presented. In order to cost effectively and robustly model the performance of several NDA techniques, an"assembly library" was created that contains a diverse range of pressurized water reactor spent fuel assemblies (burnup, enrichment, cooling time) similar to that which exists in spent pools today and in the future, diversion scenarios that capture a range of possible rod removal options, spatial and isotopic detail needed to accurately quantify the capability of all the NDA techniques so as to enable integration. Integration is being designed into this study from the beginning since it is expected that the best performance will be obtained by combining a few NDA techniques. The performance of each instrument will be quantified for the full assembly library in three different media: air, water and borated water. In this paper the preliminary capability of delayed neutron detection will be quantified for the spent fuel library for all three media. The 13 NDA techniques being researched are the following: Delayed Gamma, Delayed Neutrons, Differential Die-Away, Differential Die-Away Self-Interrogation, Lead Slowing Down Spectrometer, Neutron Multiplicity, Nuclear Resonance Fluorescence, Passive Prompt Gamma, Passive Neutron Albedo Reactivity, Self-integration Neutron Resonance Densitometry, Total Neutron (Gross Neutron), X-Ray Fluorescence, 252Cf Interrogation with Prompt Neutron Detection.

Tobin, S. J.; Sandoval, N. P.; Fensin, M. L.; Lee, S. Y.; Ludewigt, Bernhard A.; Menlovea, H. O.; Quiter, B. J.; Rajasingume, A.; Schearf, M. A.; Smith, L. E.; Swinhoe, M. T.; Thompson, S. J.

2009-06-30

16

Conceptual Ideas for New Nondestructive UF6 Cylinder Assay Techniques  

SciTech Connect

Nondestructive assay (NDA) measurements of uranium cylinders play an important role in helping the International Atomic Energy Agency (IAEA) safeguard uranium enrichment plants. Traditionally, these measurements have consisted of a scale or load cell to determine the mass of UF{sub 6} in the cylinder combined with a gamma-ray measurement of the 186 keV peak from {sup 235}U to determine enrichment. More recently, Los Alamos National Laboratory (LANL) and Pacific Northwest National Laboratory (PNNL) have developed systems that exploit the passive neutron signal from UF{sub 6} to determine uranium mass and/or enrichment. These include the Uranium Cylinder Assay System (UCAS), the Passive Neutron Enrichment Meter (PNEM), and the Hybrid Enrichment Verification Array (HEVA). The purpose of this report is to provide the IAEA with new ideas on technologies that may or may not be under active development but could be useful for UF{sub 6} cylinder assay. To begin, we have included two feasibility studies of active interrogation techniques. There is a long history of active interrogation in the field of nuclear safeguards, especially for uranium assay. Both of the active techniques provide a direct measure of {sup 235}U content. The first is an active neutron method based on the existing PNEM design that uses a correlated {sup 252}Cf interrogation source. This technique shows great promise for UF{sub 6} cylinder assay and is based on advanced technology that could be implemented in the field in the near term. The second active technique is nuclear resonance fluorescence (NRF). In the NRF technique, a bremsstrahlung photon beam could be used to illuminate the cylinder, and high-resolution gamma-ray detectors would detect the characteristic de-excitation photons. The results of the feasibility study show that under certain measurement geometries, NRF is impractical for UF6 cylinder assay, but the 'grazing transmission' and 'secant transmission' geometries have more potential for this application and should be assessed quantitatively. The next set of techniques leverage scintillator detectors that are sensitive to both neutron and gamma radiation. The first is the BC-523A capture-gated organic liquid scintillator. The detector response from several different neutron energies has been characterized and is included in the study. The BC-523A has not yet been tested with UF{sub 6} cylinders, but the application appears to be well suited for this technology. The second detector type is a relatively new inorganic scintillator called CLYC. CLYC provides a complementary detection approach to the HEVA and PNEM systems that could be used to determine uranium enrichment in UF{sub 6} cylinders. In this section, the conceptual idea for an integrated CLYC-HEVA/PNEM system is explored that could yield more precision and robustness against systemic uncertainties than any one of the systems by itself. This is followed by a feasibility study on using alpha-particle-induced reaction gamma-rays as a way to estimate {sup 234}U abundance in UF{sub 6}. Until now, there has been no readily available estimate of the strength of these reaction gamma-rays. Thick target yields of the chief reaction gammas are computed and show that they are too weak for practical safeguards applications. In special circumstances where long count times are permissible, the 1,275 keV F({alpha},x{gamma}) is observable. Its strength could help verify an operator declaration provided other knowledge is available (especially the age). The other F({alpha},x{gamma}) lines are concealed by the dominant uranium line spectrum and associated continuum. Finally, the last section provides several ideas for electromagnetic and acoustic nondestructive evaluation (NDE) techniques. These can be used to measure cylinder wall thickness, which is a source of systematic uncertainty for gamma-ray-based NDA techniques; characterize the UF{sub 6} filling profile inside the cylinder, which is a source of systematic uncertainty for neutron-based NDA techniques; locate hidden objects inside the cylinder; a

Miller, Karen A. [Los Alamos National Laboratory

2012-05-02

17

Nondestructive assay of plutonium fuel for FFTF and supporting operations  

Microsoft Academic Search

Nondestructive assay (NDA) of plutonium fuel in connection with the Fast Flux Test Facility and supporting operations at the Hanford Engineering Development Laboratory is described. Plutonium materials associated with these operations include PuO2, mixed oxide powder and pellets, fast breeder reactor fuel pins and fuel bundles, solutions, dry scrap and waste. State-of-the-art NDA instruments utilized in safeguards and material control

P. Goris; G. B. Frandsen; G. P. Gottschalk; M. C. Lambert; J. A. Petty

1981-01-01

18

Nondestructive and quantitative characterization of TRU and LLW mixed-waste using active and passive gamma-ray spectrometry and computed tomography  

Microsoft Academic Search

The technology being proposed by LLNL is an Active and Passive Computed Tomography (A P CT) Drum Scanner for contact-handled (CH) wastes. It combines the advantages offered by two well-developed nondestructive assay technologies: gamma-ray spectrometry and computed tomography (CT). Coupled together, these two technologies offer to nondestructively and quantitatively characterize mixed- wastes forms. Gamma-ray spectroscopy uses one or more external

D. C. Camp; H. E. Martz

1991-01-01

19

Selection of non-destructive assay methods: Neutron counting or calorimetric assay?  

SciTech Connect

The transition of DOE facilities from production to D&D has lead to more measurements of product, waste, scrap, and other less attractive materials. Some of these materials are difficult to analyze by either neutron counting or calorimetric assay. To determine the most efficacious analysis method, variety of materials, impure salts and hydrofluorination residues have been assayed by both calorimetric assay and neutron counting. New data will be presented together with a review of published data. The precision and accuracy of these measurements are compared to chemistry values and are reported. The contribution of the gamma ray isotopic determination measurement to the overall error of the calorimetric assay or neutron assay is examined and discussed. Other factors affecting selection of the most appropriate non-destructive assay method are listed and considered.

Cremers, T.L.; Wachter, J.R.

1994-08-01

20

Design of standards for nondestructive assay of special nuclear material  

SciTech Connect

Nondestructive assay (NDA) of special nuclear material (SNM) involves a variety of measurement techniques, instruments, and nuclear materials. High-quality measurements require well-characterized SNM standards that represent the expected range of mass, chemical composition, and physical properties of the SNM to be measured. Due to the very limited commercial availability of NDA standards, facilities must usually produce their own standards, both to meet their specific measurement needs and to comply with existing regulations. This paper will describe the current extent to which NDA standards are commercially available. The authors will further describe the types of NDA standards used to calibrate and verify the measurement techniques commonly used in the safeguards of SNM. Several types of NDA standards will be discussed in detail to illustrate the considerations that go into specifying and designing traceable, representative standards for materials accounting measurements.

Smith, H.A. Jr.; Stewart, J.E. [Los Alamos National Lab., NM (United States); Ruhter W. [Lawrence Livermore National Lab., CA (United States)

1997-05-01

21

Total Gamma Count Rate Analysis Method for Nondestructive Assay Characterization  

SciTech Connect

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.

Cecilia R. Hoffman; Yale D. Harker

2006-03-01

22

Technical Cross-Cutting Issues for the Next Generation Safeguards Initiative's Spent Fuel Nondestructive Assay Project  

SciTech Connect

Ever since there has been spent fuel (SF), researchers have made nondestructive assay (NDA) measurements of that fuel to learn about its content. In general these measurements have focused on the simplest signatures (passive photon and total neutron emission) and the analysis has often focused on diversion detection and on determining properties such as burnup (BU) and cooling time (CT). Because of shortcomings in current analysis methods, inspectorates and policy makers are interested in improving the state-of-the-art in SF NDA. For this reason the U.S. Department of Energy, through the Next Generation Safeguards Initiative (NGSI), targeted the determination of elemental Pu mass in SF as a technical goal. As part of this research effort, 14 nondestructive assay techniques were studied . This wide range of techniques was selected to allow flexibility for the various needs of the safeguards inspectorates and to prepare for the likely integration of one or more techniques having complementary features. In the course of researching this broad range of NDA techniques, several cross-cutting issues were. This paper will describe some common issues and insights. In particular we will describe the following: (1) the role of neutron absorbers with emphasis on how these absorbers vary in SF as a function of initial enrichment, BU and CT; (2) the need to partition the measured signal among different isotopic sources; and (3) the importance of the “first generation” concept which indicates the spatial location from which the signal originates as well as the isotopic origins.

Tobin, S. J.; Menlove, H. O.; Swinhoe, Martyn T.; Blanc, P.; Burr, T.; Evans, L. G.; Favalli, A.; Fensin, M. L.; Freeman, C. R.; Galloway, J.; Gerhart, J.; Rajasingam, A.; Rauch, E.; Sandoval, N. P.; Trellue, H.; Ulrich, T. J.; Conlin, J. L.; Croft, S.; Hendricks, John; Henzl, V.; Henzlova, D.; Eigenbrodt, J. M.; Koehler, W. E.; Lee, D. W.; Lee, T. H.; Lafleur, A. M.; Schear, M. A.; Humphrey, M. A.; Smith, Leon E.; Anderson, Kevin K.; Campbell, Luke W.; Casella, Andrew M.; Gesh, Christopher J.; Shaver, Mark W.; Misner, Alex C.; Amber, S. D.; Ludewigt, Bernhard A.; Quiter, B.; Solodov, Alexander; Charlton, W.; Stafford, A.; Romano, C.; Cheatham, J.; Ehinger, Michael; Thompson, S. J.; Chichester, David; Sterbentz, James; Hu, Jianwei; Hunt, A.; Mozin, Vladimir V.; Richard, J. G.

2012-03-01

23

Use of neutron-capture plastic fibers for nondestructive assay  

SciTech Connect

Neutron-capture plastic fibers can be used as a nondestructive assay tool. The detectors consist of an active region assembled from ribbons of boron-({sup 10}B) loaded optical fibers. The mixture of the moderator and thermal neutron absorber in the fiber yields a detector with high efficiency ({var_epsilon}) and a short die-away time ({tau}). The deposited energy of the resultant charged particles is converted to light that is collected by photomultiplier tubes mounted at both ends of the fiber. Thermal neutron coincidence counters (TNCC) made of these fibers can serve to verify fissile materials generated from the nuclear fuel cycle. This type of detector may extend the range of materials now accessible to assay by {sup 3}He detectors. Experiments with single fibers of diameters 0.25, 0.50, and 1.00 mm test their ability to distinguish between the signals generated from neutron interactions and those from gamma rays. These results are compared with those obtained from simulation analyses for the same purpose. Light output and attenuation, neutron detection efficiency, and the signal-to-noise ratios of these fibers have also been investigated. The experimental results for light attenuation and neutron detection efficiency are consistent with the values obtained from simulation studies. A comparison of the performance of various configurations of the plastic scintillating fibers with that of other neutron-capture devices such as {sup 3}He detectors is also discussed.

Heger, A.S.; Grazioso, R.F.; Mayo, D.R.; Ensslin, N.; Miller, M.C.; Huang, H.Y.; Russo, P.A.

1998-12-31

24

Nondestructive Spent Fuel Assay Using Nuclear Resonance Fluorescence  

SciTech Connect

Quantifying the isotopic composition of spent fuel is an important challenge and essential for many nuclear safeguards applications, such as independent verification of the Pu content declared by a regulated facility, shipper/receiver measurements, and quantifying isotopic input masses at a reprocessing facility. As part of the Next Generation Safeguards Initiative, NA-241 has recently funded a multilab/university collaboration to investigate a variety of nondestructive methods for determining the elemental Pu mass in spent fuel assemblies. Nuclear resonance fluorescence (NRF) is one of the methods being investigated. First modeling studies have been performed to investigate the feasibility of assaying a single fuel pin using a bremsstrahlung photon source. MCNPX modeling results indicate that NRF signals are significantly more intense than the background due to scattered interrogation photons even for isotopes with concentrations below 1percent. However, the studies revealed that the dominant contribution to the background is elastic scattering, which is currently not simulated by MCNPX. Critical to this effort, we have added existing NRF data to the MCNPX photonuclear data files and are now able to incorporate NRF physics into MCNPX simulations. Addition of the non-resonant elastic scattering data to MCNPX is in progress. Assaying fuel assemblies with NRF poses additional challenges: photon penetration through the assembly is small and the spent fuel radioactive decay and neutron activity lead to significantly higher backgrounds. First modeling studies to evaluate the efficacy of NRF for assaying assemblies have been initiated using the spent fuel assembly library created at the Los Alamos National Laboratory (LANL).

Quiter, Brian; Ludewigt, Bernhard; Mozin, Vladimir; Tobin, Steven

2009-07-01

25

Evaluation of Nondestructive Assay/Nondestructive Examination Capabilities for Department of Energy Spent Nuclear Fuel  

SciTech Connect

This report summarizes an evaluation of the potential use of nondestructive assay (NDA) and nondestructive examination (NDE) technologies on DOE spent nuclear fuel (SNF). It presents the NDA/NDE information necessary for the National Spent Nuclear Fuel Program (NSNFP) and the SNF storage sites to use when defining that role, if any, of NDA/NDE in characterization and certification processes. Note that the potential role for NDA/NDE includes confirmatory testing on a sampling basis and is not restricted to use as a primary, item-specific, data collection method. The evaluation does not attempt to serve as a basis for selecting systems for development or deployment. Information was collected on 27 systems being developed at eight DOE locations. The systems considered are developed to some degree, but are not ready for deployment on the full range of DOE SNF and still require additional development. The system development may only involve demonstrating performance on additional SNF, packaging the system for deployment, and developing calibration standards, or it may be as extensive as performing additional basic research. Development time is considered to range from one to four years. We conclude that NDA/NDE systems are capable of playing a key role in the characterization and certification of DOE SNF, either as the primary data source or as a confirmatory test. NDA/NDE systems will be able to measure seven of the nine key SNF properties and to derive data for the two key properties not measured directly. The anticipated performance goals of these key properties are considered achievable except for enrichment measurements on fuels near 20% enrichment. NDA/NDE systems can likely be developed to measure the standard canisters now being considered for co-disposal of DOE SNF. This ability would allow the preparation of DOE SNF for storage now and the characterization and certification to be finalize later.

Luptak, A.J.; Bulmahn, K.D.

1998-09-01

26

Unattended mode operation of specialized NDA (nondestructive assay) systems  

SciTech Connect

Nondestructive assay systems have been developed to allow data acquisition equipment to operate unattended in an automated mixed oxide facility, reducing inspector time in a facility and giving them time for other activities. Fewer inspector visits mean less impact on plant operators. Neutron detectors are located at key measurement points in the facility. Near each detector is located an electronics cabinet, which contains two JSR-11 shift registers, two COMPAQ Portable III computers, and a printer. The signal from the detector is split and sent to each shift register for redundancy and reliability. The software for unattended operation consists primarily of two programs, COLLECT and REVIEW. The COLLECT program runs on the computers in unattended operation; shift-register data are acquired each 60 s. The COLLECT program distinguishes between a normal background and a disconnected signal, between material moving near the detector and material in the detector, and whether the material in the detector is a sample or a californium normalization source. Depending on the type of assay, different data are stored on the hard disk. During an inspection, the inspector stops the current measurement campaign, examines the data from both computers briefly at the electronics cabinet, copies the campaign data to floppy disk, and starts another measurement campaign. These data are examined later in another location using the REVIEW program running on high performance microcomputers: a COMPAQ DeskPro 386/20 or equivalent. The REVIEW program uses graphical displays to enable the inspector to quickly search through the massive amounts of accumulated data to learn when samples were measured. Data from the desired measurements are then transferred to the International Atomic Energy Agency high-level neutron coincidence program for further analysis. 3 refs., 7 figs.

Klosterbuer, S.F.; Kern, E.A.; Painter, J.A.; Takahashi, S.

1989-01-01

27

Nondestructive and quantitative characterization of TRU and LLW mixed-waste using active and passive gamma-ray spectrometry and computed tomography  

SciTech Connect

The technology being proposed by LLNL is an Active and Passive Computed Tomography (A P CT) Drum Scanner for contact-handled (CH) wastes. It combines the advantages offered by two well-developed nondestructive assay technologies: gamma-ray spectrometry and computed tomography (CT). Coupled together, these two technologies offer to nondestructively and quantitatively characterize mixed- wastes forms. Gamma-ray spectroscopy uses one or more external radiation detectors to passively and nondestructively measure the energy spectrum emitted from a closed container. From the resulting spectrum one can identify most radioactivities detected, be they transuranic isotopes, mixed-fission products, activation products or environmental radioactivities. Spectral libraries exist at LLNL for all four. Active (A) or transmission CT is a well-developed, nondestructive medical and industrial technique that uses an external-radiation beam to map regions of varying attenuation within a container. Passive (P) or emission CT is a technique mainly developed for medical application, e.g., single-photon emission CT. Nondestructive industrial uses of PCT are under development and just coming into use. This report discuses work on the A P CT Drum Scanner at LLNL.

Camp, D.C.; Martz, H.E.

1991-11-12

28

LANL`s mobile nondestructive assay and examination systems for radioactive wastes  

SciTech Connect

The ability to accurately and rapidly measure nuclear material within drums and examine their contents without having to unpack the drums saves time, reduces characterization costs and minimizes radiation exposure. Over the past two years, Los Alamos National Laboratory (LANL) has developed and fielded a suite of mobile nondestructive assay and examination systems for use primarily on its own transuranic (TRU) waste but that also have application to low level, mixed and hazardous wastes. It has become obvious that systems like these are generally useful and have applications at other Department of Energy (DOE) production and environmental technology sites. Mobile capabilities present a potential cost savings where waste drums have to be transported to a fixed NDA facility. In other cases they fill a void where there is no fixed facility available because construction costs are prohibitive (as in the case of small quantity sites) or the available facilities may not meet current or evolving safety standards. Rather than bringing waste to a facility to be characterized, one can bring the characterization capability to the waste. The three systems described are: (1) mobile radiography system; (2) mobile segmented/tomographic gamma scanner; and (3) mobile passive/active neutron assay system.

Taggart, D.P. Betts, S.E.; Vigil, J.J.

1996-04-09

29

Transuranic and Low-Level Boxed Waste Form Nondestructive Assay Technology Overview and Assessment  

SciTech Connect

The Mixed Waste Focus Area (MWFA) identified the need to perform an assessment of the functionality and performance of existing nondestructive assay (NDA) techniques relative to the low-level and transuranic waste inventory packaged in large-volume box-type containers. The primary objectives of this assessment were to: (1) determine the capability of existing boxed waste form NDA technology to comply with applicable waste radiological characterization requirements, (2) determine deficiencies associated with existing boxed waste assay technology implementation strategies, and (3) recommend a path forward for future technology development activities, if required. Based on this assessment, it is recommended that a boxed waste NDA development and demonstration project that expands the existing boxed waste NDA capability to accommodate the indicated deficiency set be implemented. To ensure that technology will be commercially available in a timely fashion, it is recommended this development and demonstration project be directed to the private sector. It is further recommended that the box NDA technology be of an innovative design incorporating sufficient NDA modalities, e.g., passive neutron, gamma, etc., to address the majority of the boxed waste inventory. The overall design should be modular such that subsets of the overall NDA system can be combined in optimal configurations tailored to differing waste types.

G. Becker; M. Connolly; M. McIlwain

1999-02-01

30

Nondestructive assay tests of high-efficiency neutron counter (HENC) for waste assay and possible diversion scenario  

Microsoft Academic Search

An advanced passive neutron counter, the high-efficiency neutron counter (HENC), has been used to measure plutonium content in 200-L waste drums. The HENC was designed with the ²⁵²Cf add-a-source (AS) feature to improve accuracy over a wide range of waste matrix materials. The current implementation allows for passive neutron coincidence counting, AS analysis, and multiplicity analysis. Passive neutron assay of

D. R. Mayo; H. O. Menlove; J. M. Pecos

1998-01-01

31

Active nondestructive assay of nuclear materials: principles and applications  

SciTech Connect

The purpose of this book is to present, coherently and comprehensively, the wealth of available but scattered information on the principles and applications of active nondestructive analysis (ANDA). Chapters are devoted to the following: background and overview; interactions of neutrons with matter; interactions of ..gamma..-rays with matter; neutron production and sources; ..gamma..-ray production and sources; effects of neutron and ..gamma..-ray transport in bulk media; signatures of neutron- and photon-induced fissions; neutron and photon detection systems and electronics; representative ANDA systems; and instrument analysis, calibration, and measurement control for ANDA. Each chapter has an introductory section describing the relationship of the topic of that chapter to ANDA. Each chapter ends with a section that summarizes the main results and conclusions of the chapter, and a reference list.

Gozani, Tsahi

1981-01-01

32

Field experience with a mobile tomographic nondestructive assay system  

SciTech Connect

A mobile tomographic gamma-ray scanner (TGS) developed by Los Alamos National Laboratory was recently demonstrated at the Rocky Flats Environmental Technology Site and is currently in use at Los Alamos waste storage areas. The scanner was developed to assay radionuclides in low-level, transuranic, and mixed waste in containers ranging in size from 2 ft{sup 3} boxes to 83-gallon overpacks. The tomographic imaging capability provides a complete correction for source distribution and matrix attenuation effects, enabling accurate assays of Pu-239 and other gamma-ray emitting isotopes. In addition, the system can reliably detect self-absorbing material such as plutonium metal shot, and can correct for bias caused by self-absorption. The system can be quickly configured to execute far-field scans, segmented gamma-ray scans, and a host of intermediate scanning protocols, enabling higher throughput (up to 20 drums per 8-hour shift). In this paper, we will report on the results of field trials of the mobile system at Rocky Flats and Los Alamos. Assay accuracy is confirmed for cases in which TGS assays can be compared with assays (e.g. with calorimetry) of individual packages within the drums. The mobile tomographic technology is expected to considerably reduce characterization costs at DOE production and environmental technology sites.

Prettyman, T.H.; Betts, S.E.; Taggart, D.P.; Estep, R.J.; Nicholas, N.J.; Lucas, M.C.; Harlan, R.A.

1995-12-01

33

Automated Nondestructive Assay of UF6 Cylinders: Detector Characterization and Initial Measurements  

SciTech Connect

International Atomic Energy Agency (IAEA) inspectors currently perform periodic inspections at uranium enrichment plants to verify UF6 cylinder enrichment declarations. Measurements are typically performed with handheld high-resolution sensors on a sampling of cylinders assumed to be representative of the facility's entire cylinder inventory. These measurements are time-consuming and assay only a small fraction of the total cylinder volume. An automated nondestructive assay system capable of providing enrichment measurements over the full volume of the cylinder could improve upon current verification practices in terms of manpower and assay accuracy. Pacific Northwest National Laboratory is developing an Integrated Cylinder Verification System (ICVS) intended for this purpose and has developed a field prototype of the nondestructive assay (NDA) components of an ICVS. The nondestructive assay methods would combine the 'traditional' enrichment-meter signature (i.e. 186-keV emission from 235U) as well as 'non-traditional' high-energy photon signatures derived from neutrons produced primarily by 19F({alpha},n) reactions. This paper describes the design, calibration and characterization of the NaI(Tl) and LaBr3(Ce) spectrometers utilized in the field prototype. An overview of a recent field measurement campaign is then provided, supported by example gamma-ray pulse-height spectra collected on cylinders of known enrichment.

Mace, Emily K.; Smith, Leon E.

2011-10-01

34

MONTE CARLO ERROR ESTIMATION APPLIED TO NONDESTRUCTIVE ASSAY METHODS  

SciTech Connect

Monte Carlo randomization of nuclear counting data into N replicate sets is the basis of a simple and effective method for estimating error propagation through complex analysis algorithms such as those using neural networks or tomographic image reconstructions. The error distributions of properly simulated replicate data sets mimic those of actual replicate measurements and can be used to estimate the std. dev. for an assay along with other statistical quantities. We have used this technique to estimate the standard deviation in radionuclide masses determined using the tomographic gamma scanner (TGS) and combined thermal/epithermal neutron (CTEN) methods. The effectiveness of this approach is demonstrated by a comparison of our Monte Carlo error estimates with the error distributions in actual replicate measurements and simulations of measurements. We found that the std. dev. estimated this way quickly converges to an accurate value on average and has a predictable error distribution similar to N actual repeat measurements. The main drawback of the Monte Carlo method is that N additional analyses of the data are required, which may be prohibitively time consuming with slow analysis algorithms.

R. ESTEP; ET AL

2000-06-01

35

Radiometric measurements on non-destructive assay standards fabrication for WIPP Performance Demonstration Program  

Microsoft Academic Search

The Inorganic Elemental Analysis Group of LANL has prepared several different sets of working reference materials (WRMs).\\u000a These WRMs are prepared by blending quantities of nuclear materials (plutonium, americium, and enriched uranium) with diatomaceous\\u000a earth. The blends are encapsulated in stainless steel cylinders. These WRMs are being measured as blind controls in neutron\\u000a and gamma based non-destructive assay (NDA) instruments.

A. S. Wong; R. S. Marshall

1998-01-01

36

Considerations for an active and passive scanner to assay nuclear waste drums  

SciTech Connect

Radioactive wastes are generated at many DOE laboratories, military facilities, fuel fabrication and enrichment plants, reactors, hospitals, and university research facilities. At all of these sites, wastes must be separated, packaged, categorized, and packed into some sort of container--usually 208-L (55-gal) drums--for shipment to waste-storage sites. Prior to shipment, the containers must be labeled, assayed, and certified; the assay value determines the ultimate disposition of the waste containers. An accurate nondestructive assay (NDA) method would identify all the radioisotopes present and provide a quantitative measurement of their activity in the drum. In this way, waste containers could be routed in the most cost-effective manner and without having to reopen them. Currently, the most common gamma-ray method used to assay nuclear waste drums is segmented gamma-ray scanning (SGS) spectrometer that crudely measures only the amount of {sup 235}U or {sup 239}Pu present in the drum. This method uses a spatially-averaged, integrated, emitted gamma-ray-intensity value. The emitted intensity value is corrected by an assumed constant-attenuation value determined by a spatially-averaged, transmission (or active) measurement. Unfortunately, this typically results in an inaccurate determination of the radioactive activities within a waste drum because this measurement technique is valid only for homogeneous-attenuation or known drum matrices. However, since homogeneous-attenuation matrices are not common and may be unknown, other NDA techniques based on active and Passive CT (A PCT) are under development. The active measurement (ACT) yields a better attenuation matrix for the drum, while the passive measurement (PCT) more accurately determines the identity of the radioisotopes present and their activities. 9 refs., 2 figs.

Martz, H.E.; Azevedo, S.G.; Roberson, G.P.; Schneberk, D.J.; Koenig, Z.M.; Camp, D.C. (Lawrence Livermore National Lab., CA (USA))

1990-06-08

37

Install active/passive neutron examination and assay (APNEA)  

SciTech Connect

This document describes activities pertinent to the installation of the prototype Active/Passive Neutron Examination and Assay (APNEA) system built in Area 336 into its specially designed trailer. It also documents the basic theory of operation, design and protective features, basic personnel training, and the proposed characterization site location at Lockheed Martin Specialty Components, Inc., (Specialty Components) with the estimated 10 mrem/year boundary. Additionally, the document includes the Preventive Change Analysis (PCA) form, and a checklist of items for verification prior to unrestricted system use.

Not Available

1996-04-01

38

Gamma ray scanner systems for nondestructive assay of heterogeneous waste barrels  

SciTech Connect

Traditional gamma measurement errors are related to non-uniform measurement responses associated with unknown radioactive source and matrix material distributions. These errors can be reduced by application of tomographic techniques that measure these distributions. LLNL has developed two tomographic-based waste assay systems. They use external radioactive sources and tomography-protocol to map the attenuation within a waste barrel as a function of mono-energetic gamma-ray energy in waste containers. Passive tomography is used to localize and identify specific radioactive waste contents within the same waste containers. Reconstruction of the passive data via the active images allows internal waste radioactivities in a barrel to be corrected for any overlying heterogeneous materials, thus yielding an absolute assay of the waste radioactivities. Calibration of both systems requires only point source measurements and are independent of matrix materials.

Martz, H.E.; Roberson, G.P.; Decman, D.J.; Camp, D.C. [Lawrence Livermore National Lab., CA (United States); Levai, F. [Institute of Nuclear Techniques, Technical University of Budapest (Hungary)

1997-08-01

39

Non-destructive Assay Measurements Using the RPI Lead Slowing Down Spectrometer  

SciTech Connect

The use of a Lead Slowing-Down Spectrometer (LSDS) is consid- ered as a possible option for non-destructive assay of fissile material of used nuclear fuel. The primary objective is to quantify the 239Pu and 235U fissile content via a direct measurement, distinguishing them through their characteristic fission spectra in the LSDS. In this pa- per, we present several assay measurements performed at the Rensse- laer Polytechnic Institute (RPI) to demonstrate the feasibility of such a method and to provide benchmark experiments for Monte Carlo cal- culations of the assay system. A fresh UOX fuel rod from the RPI Criticality Research Facility, a 239PuBe source and several highly en- riched 235U discs were assayed in the LSDS. The characteristic fission spectra were measured with 238U and 232Th threshold fission cham- bers, which are only sensitive to fission neutron with energy above the threshold. Despite the constant neutron and gamma background from the PuBe source and the intense interrogation neutron flux, the LSDS system was able to measure the characteristic 235U and 239Pu responses. All measurements were compared to Monte Carlo simula- tions. It was shown that the available simulation tools and models are well suited to simulate the assay, and that it is possible to calculate the absolute count rate in all investigated cases.

Becker, Bjorn; Weltz, Adam; Kulisek, Jonathan A.; Thompson, J. T.; Thompson, N.; Danon, Yaron

2013-10-01

40

Performance Demonstration Program Plan for Nondestructive Assay for the TRU Waste Characterization Program. Revision 1  

SciTech Connect

The Performance Demonstration Program (PDP) for Nondestructive Assay (NDA) consists of a series of tests conducted on a regular frequency to evaluate the capability for nondestructive assay of transuranic (TRU) waste throughout the Department of Energy (DOE) complex. Each test is termed a PDP cycle. These evaluation cycles provide an objective measure of the reliability of measurements performed with TRU waste characterization systems. Measurement facility performance will be demonstrated by the successful analysis of blind audit samples according to the criteria set by this Program Plan. Intercomparison between measurement groups of the DOE complex will be achieved by comparing the results of measurements on similar or identical blind samples reported by the different measurement facilities. Blind audit samples (hereinafter referred to as PDP samples) will be used as an independent means to assess the performance of measurement groups regarding compliance with established Quality Assurance Objectives (QAOs). As defined for this program, a PDP sample consists of a 55-gallon matrix drum emplaced with radioactive standards and fabricated matrix inserts. These PDP sample components, once manufactured, will be secured and stored at each participating measurement facility designated and authorized by Carlsbad Area Office (CAO) under secure conditions to protect them from loss, tampering, or accidental damage.

None

1997-05-01

41

Multi-isotopic transuranic waste interrogation using delayed neutron nondestructive assay and iterative quadratic programming techniques  

NASA Astrophysics Data System (ADS)

Nuclear safeguards for Special Nuclear Materials is to protect the nuclear materials against malevolent use and to insure their peaceful usage. The nondestructive assay technique (NDA) offers an efficient and proliferation resistance method for nuclear safeguards technology. NDA techniques were investigated for multi-isotopic transuranic waste interrogation. This work was originally intended for the Integral Fast Reactor (IFR) under development at Argonne National Laboratory. One major feature of the IFR is its integral fuel cycle based on a pyrometallurgical process. More than 99% of transuranics produced in the fuel are returned to the makeup fuel and burned in the reactor. With the long-lived actinides removed from the waste stream, the waste produced will decay sufficiently in 300 years dropping below the cancer risk level of natural uranium ore and easing the perceived waste management problem. The feasibility of using nondestructive assay techniques for the IFR fuel cycle waste interrogation were studied. A special DNNDA experimental device was designed and analysis techniques were developed. The DNNDA technique uses the delayed neutrons emitted after the activation of a 14 MeV neutron source as the characteristic signature for each fissionable isotope. A tantalum/polyethylene filter was employed to enhance the discrimination between the fissile and the fissionable isotopes. Spontaneous fissions from 240Pu were also measured to assist the mass assay. A nonlinear overdetermined system was established based on the DNNDA measurements. An Iterative Quadratic Programming (IQP) method was applied to perform the estimates. The IQP method has several advantages over the linear least squares and Kalman filter methods, it has the flexibility of adding additional constraints, it has superlinear global convergence and it can be utilized for nonlinear problems. The results show that using the IQP method with the DNNDA technique is quite promising for multi-isotopic assay in the range of one gram to 50 grams. Sensitivity analyses show that the IQP method is very insensitive to the a priori. A 5% error of mass assay is achievable with one sigma of uncertainty for good calibration data and assay measurement statistics.

Wu, Cheng-Wei

1997-11-01

42

Application of Laser Compton Scattered gamma-ray beams to nondestructive detection and assay of nuclear material  

NASA Astrophysics Data System (ADS)

Generation of energy-tunable gamma-rays via Laser Compton Scattering is of great interest for scientific studies and applications of "MeV" photons which interact with nuclei. One of the promising applications of such energy-tunable gamma-rays is the nondestructive detection and assay of nuclides which are necessary for nuclear security and safeguards. We are developing technologies relevant to gamma-ray nondestructive detection and assay, which include a high-brightness gamma-ray source based on modern laser and accelerator technologies, and gamma-ray measurement methods optimized for highly radioactive samples.

Hajima, R.; Hayakawa, T.; Shizuma, T.; Angell, C. T.; Nagai, R.; Nishimori, N.; Sawamura, M.; Matsuba, S.; Kosuge, A.; Mori, M.; Seya, M.

2014-05-01

43

QA Objectives for Nondestructive Assay at the Waste Receiving & Processing (WRAP) Facility  

SciTech Connect

The Waste Receiving and Processing (WRAP) facility, located on the Word Site in southeast Washington, is a key link in the certification of transuranic (TRU) waste for shipment to the Waste Isolation Pilot Plant (WIPP). Waste characterization is one of the vital functions performed at WRAP, and nondestructive assay (NDA) measurements of TRU waste containers is one of two required methods used for waste characterization. The Waste Acceptance Criteria for the Waste Isolation Pilot Plant, DOE/WIPP-069 (WIPP-WAC) delineates the quality assurance objectives which have been established for NDA measurement systems. Sites must demonstrate that the quality assurance objectives can be achieved for each radioassay system over the applicable ranges of measurement. This report summarizes the validation of the WRAP NDA systems against the radioassay quality assurance objectives or QAOs. A brief description of the each test and significant conclusions are included. Variables that may have affected test outcomes and system response are also addressed.

CANTALOUB, M.G.

2000-08-01

44

QA Objectives for Nondestructive Assay at the Waste Receiving and Processing (WRAP) Facility  

SciTech Connect

The Waste Receiving and Processing (WRAP) facility, located on the Hanford Site in southeast Washington, is a key link in the certification of transuranic (TRU) waste for shipment to the Waste Isolation Pilot Plant (WIPP). Waste characterization is one of the vital functions performed at WRAP, and nondestructive assay (NDA) measurements of TRU waste containers is one of two required methods used for waste characterization. The Waste Acceptance Criteria for the Waste Isolation Pilot Plant, DOEMPP-069 (WIPP-WAC) delineates the quality assurance objectives which have been established for NDA measurement systems. Sites must demonstrate that the quality assurance objectives can be achieved for each radioassay system over the applicable ranges of measurement. This report summarizes the validation of the WRAP NDA systems against the radioassay quality assurance objectives or QAOs. A brief description of the each test and significant conclusions are included. Variables that may have affected test outcomes and system response are also addressed.

CANTALOUB, M.G.; WILLS, C.E.

2000-03-24

45

Radiometric measurements on the fabrication of non-destructive assay standards for WIPP-Performance Demonstration Program  

Microsoft Academic Search

The Inorganic Elemental Analysis Group of LANL has prepared several different sets of working reference materials (WRMs). These WRMs are prepared by blending quantities of nuclear materials (plutonium, americium, and enriched uranium) with diatomaceous earth. The blends are encapsulated in stainless steel cylinders. These WRMs are being measured as blind controls in neutron and gamma based non-destructive assay (NDA) instruments.

A. S. Wong; R. S. Marshall

1997-01-01

46

A new facility for Non-Destructive Assay with a time-tagged {sup 252}Cf source  

SciTech Connect

A new facility for non-destructive assay using a time-tagged {sup 252}Cf source is presented. The system is designed to analyze samples having maximum size of about 15x20 cm{sup 2}, the material recognition being obtained by measuring simultaneously transmission of neutrons and gamma rays.

Stevanato, L.; Caldogno, M.; Hao Xin [Dipartimento di Fisica, Universita di Padova, Via Marzolo 8, I-35131 Padova (Italy); Dima, R.; Fabris, D.; Nebbia, G. [INFN Sezione di Padova, Via Marzolo 8, I-35131 Padova (Italy); Lunardon, M.; Moretto, S.; Pesente, S.; Viesti, G. [Dipartimento di Fisica, Universita di Padova, Via Marzolo 8, I-35131 Padova (Italy); INFN Sezione di Padova, Via Marzolo 8, I-35131 Padova (Italy); Sajo-Bohus, L. [Laboratorio de Fisica Nuclear, Universidad Simon Bolivar, Apartado 89000, 1080 A Caracas (Venezuela, Bolivarian Republic of)

2010-08-04

47

Signatures and Methods for the Automated Nondestructive Assay of UF6 Cylinders at Uranium Enrichment Plants  

SciTech Connect

International Atomic Energy Agency (IAEA) inspectors currently perform periodic inspections at uranium enrichment plants to verify UF6 cylinder enrichment declarations. Measurements are typically performed with handheld high-resolution sensors on a sampling of cylinders taken to be representative of the facility’s entire cylinder inventory. These measurements are time-consuming, expensive, and assay only a small fraction of the total cylinder volume. An automated nondestructive assay system capable of providing enrichment measurements over the full volume of the cylinder could improve upon current verification practices in terms of manpower and assay accuracy. Such a station would use sensors that can be operated in an unattended mode at an industrial facility: medium-resolution scintillators for gamma-ray spectroscopy (e.g., NaI(Tl)) and moderated He-3 neutron detectors. This sensor combination allows the exploitation of additional, more-penetrating signatures beyond the traditional 185-keV emission from U-235: neutrons produced from F-19(?,n) reactions (spawned primarily from U 234 alpha emission) and high-energy gamma rays (extending up to 8 MeV) induced by neutrons interacting in the steel cylinder. This paper describes a study of these non-traditional signatures for the purposes of cylinder enrichment verification. The signatures and the radiation sensors designed to collect them are described, as are proof-of-principle cylinder measurements and analyses. Key sources of systematic uncertainty in the non-traditional signatures are discussed, and the potential benefits of utilizing these non-traditional signatures, in concert with an automated form of the traditional 185-keV-based assay, are discussed.

Smith, Leon E.; Mace, Emily K.; Misner, Alex C.; Shaver, Mark W.

2010-08-08

48

Bremsstrahlung-induced highly penetrating probes for nondestructive assay and defect analysis  

NASA Astrophysics Data System (ADS)

Nondestructive assay and defect analysis probes based on bremsstrahlung-induced processes have been developed to identify elements and probe defects in large volume samples. Bremsstrahlung beams from (electron accelerators) with end-point energies both above and below neutron emission threshold have been used. Below neutron emission threshold these beams (from 6 MeV small pulsed linacs), which exhibit high penetration, create positrons via pair production inside the material and produce X-ray fluorescence (XRF) radiation. Chemical assays of heavy elements in thick samples up to 10 g/cm 2 thick are provided by energy dispersive XRF measurements. The pair-produced positrons annihilate within the material, thereby emitting 511 keV gamma radiation. Doppler broadening spectroscopy of the 511 keV radiation can be performed to characterize the material and measure defects in samples of any desired thickness. This technique has successfully measured induced strain due to tensile stress in steel samples of 0.64 cm thick. Bremsstrahlung beams above neutron emission threshold, from a 20 MeV pulsed electron linac, have also been used to produce residual nuclei in excited states via photonuclear reactions allowing the detection of heavy elements via their characteristic ?-rays. This can be developed into a technique to trace some heavy metals in large rocks and soils for environmental applications.

Selim, F. A.; Wells, D. P.; Harmon, J. F.; Kwofie, J.; Spaulding, R.; Erickson, G.; Roney, T.

2002-12-01

49

Comparison of Passive Hemagglutination with Turkey Erythrocyte Assay, Enzyme-Linked Immunosorbent Assay, and Counterimmunoelectrophoresis Assay for Serological Evaluation of Tetanus Immunity  

PubMed Central

Antibody titers to tetanus toxin in human sera were assayed by passive hemagglutination with turkey erythrocytes, enzyme-linked immunosorbent assay, and counterimmunoelectrophoresis. The first two of these tests were shown to be the most sensitive for antibody detection, having the same range of sensitivity and reproducibility. The antibody levels determined by these assays were up to 400-fold higher than those determined by counterimmunoelectrophoresis. The turkey erythrocyte hemagglutination assay requires only 40 min, whereas the immunosorbent assay method requires 24 h. These results suggest that the hemagglutination assay is the more appropriate method for rapid and sensitive determination of tetanus antibody levels. PMID:16789271

Pitzurra, L.; Bistoni, F.; Pitzurra, M.; Bastianini, L.; Perito, S.; Vecchiarelli, A.; Marconi, P.

1983-01-01

50

A passive-active neutron device for assaying remote-handled transuranic waste  

SciTech Connect

A combined passive-active neutron assay device was constructed for assaying remote-handled transuranic waste. A study of matrix and source position effects in active assays showed that a knowledge of the source position alone is not sufficient to correct for position-related errors in highly moderating or absorbing matrices. An alternate function for the active assay of solid fuel pellets was derived, although the efficacy of this approach remains to be established. 4 refs., 7 figs., 1 tab.

Estep, R.J.; Coop, K.L.; Deane, T.M.; Lujan, J.E.

1989-01-01

51

Nondestructive determination of plutonium mass in spent fuel: prelliminary modeling results using the passive neutron Albedo reactivity technique  

SciTech Connect

There are a variety of motivations for quantifying plutonium (Pu) in spent fuel assemblies by means of nondestructive assay (NDA) including the following: strengthening the capability of the International Atomic Energy Agency (LAEA) to safeguard nuclear facilities, quantifying shipper/receiver difference, determining the input accountability value at pyrochemical processing facilities, providing quantitative input to burnup credit and final safeguards measurements at a long-term repository. In order to determine Pu mass in spent fuel assemblies, thirteen NDA techniques were identified that provide information about the composition of an assembly. A key motivation of the present research is the realization that none of these techniques, in isolation, is capable of both (1) quantifying the Pu mass of an assembly and (2) detecting the diversion of a significant number of rods. It is therefore anticipated that a combination of techniques will be required. A 5 year effort funded by the Next Generation Safeguards Initiative (NGSI) of the U.S. DOE was recently started in pursuit of these goals. The first two years involves researching all thirteen techniques using Monte Carlo modeling while the final three years involves fabricating hardware and measuring spent fuel. Here, we present the work in two main parts: (1) an overview of this NGSI effort describing the motivations and approach being taken; (2) The preliminary results for one of the NDA techniques - Passive Neutron Albedo Reactivity (PNAR). The PNAR technique functions by using the intrinsic neutron emission of the fuel (primarily from the spontaneous fission of curium) to self-interrogate any fissile material present. Two separate measurements of the spent fuel are made, both with and without cadmium (Cd) present. The ratios of the Singles, Doubles and Triples count rates obtained in each case are analyzed; known as the Cd ratio. The primary differences between the two measurements are the neutron energy spectrum and fluence in the spent fuel. By varying the thickness of the cadmium layer surrounding the spent fuel, a high and a low neutron-energy-measurement condition can be produced. The neutron detectors can be used to detect total neutrons (Singles) and/or Doubles and/or Triples. If the geometry of the measurement situation is unchanged between the two measurements, the change in the Cd ratio between these two measurements can be attributed to a change in the fissile content of the sample.

Evans, Louise G [Los Alamos National Laboratory; Tobin, Stephen J [Los Alamos National Laboratory; Schear, Melissa A [Los Alamos National Laboratory; Menlove, Howard O [Los Alamos National Laboratory; Lee, Sang Y [Los Alamos National Laboratory; Swinhoe, Martyn T [Los Alamos National Laboratory

2009-01-01

52

Determination of the radionuclide release factor for an evaporator process using nondestructive assay  

SciTech Connect

The 242-A Evaporator is the primary waste evaporator for the Hanford Site radioactive liquid waste stored in underground double-shell tanks. Low pressure evaporation is used to remove water from the waste, thus reducing the amount of tank space required for storage. The process produces a concentrated slurry, a process condensate, and an offgas. The offgas exhausts through two stages of high-efficiency particulate air (HEPA) filters before being discharged to the atmosphere 40 CFR 61 Subpart H requires assessment of the unfiltered exhaust to determine if continuous compliant sampling is required. Because potential (unfiltered) emissions are not measured, methods have been developed to estimate these emissions. One of the methods accepted by the Environmental Protection Agency is the measurement of the accumulation of radionuclides on the HEPA filters. Nondestructive assay (NDA) was selected for determining the accumulation on the HEPA filters. NDA was performed on the HEPA filters before and after a campaign in 1997. NDA results indicate that 2.1 E+4 becquerels of cesium-137 were accumulated on the primary HEPA 1700 filter during the campaign. The feed material processed in the campaign contained a total of 1.4 E+l6 Bq of cesium-137. The release factor for the evaporator process is 1.5 E-12. Based on this release factor, continuous compliant sampling is not required.

Johnson, R.E.

1998-07-06

53

Methods for nondestructive assay holdup measurements in shutdown uranium enrichment facilities  

SciTech Connect

Measurement surveys of uranium holdup using nondestructive assay (NDA) techniques are being conducted for shutdown gaseous diffusion facilities at the Oak Ridge K-25 Site (formerly the Oak Ridge Gaseous Diffusion Plant). When in operation, these facilities processed UF{sub 6} with enrichments ranging from 0.2 to 93 wt % {sup 235}U. Following final shutdown of all process facilities, NDA surveys were initiated to provide process holdup data for the planning and implementation of decontamination and decommissioning activities. A three-step process is used to locate and quantify deposits: (1) high-resolution gamma-ray measurements are performed to generally define the relative abundances of radioisotopes present, (2) sizable deposits are identified using gamma-ray scanning methods, and (3) the deposits are quantified using neutron measurement methods. Following initial quantitative measurements, deposit sizes are calculated; high-resolution gamma-ray measurements are then performed on the items containing large deposits. The quantitative estimates for the large deposits are refined on the basis of these measurements. Facility management is using the results of the survey to support a variety of activities including isolation and removal of large deposits; performing health, safety, and environmental analyses; and improving facility nuclear material control and accountability records. 3 refs., 1 tab.

Hagenauer, R.C.; Mayer, R.L. II.

1991-09-01

54

Development of a neutron measurement system in unified non-destructive assay for the PRIDE facility  

NASA Astrophysics Data System (ADS)

The Korea Atomic Energy Research Institute (KAERI) has made an effort to develop pyroprocessing technology to resolve an on-going problem in Korea, i.e., the management of spent nuclear fuels. To this end, a test-bed facility for pyroprocessing, called PRIDE (PyRoprocessing Integrated inactive DEmonstration facility), is being constructed at KAERI. The main objective of PRIDE is to evaluate the performance of the unit processes, remote operation, maintenance, and proliferation resistance. In addition, integrating all unit processes into a one-step process is also one of the main goals. PRIDE can also provide a good opportunity to test safeguards instrumentations for a pyroprocessing facility such as nuclear material accounting devices, surveillance systems, radiation monitoring systems, and process monitoring systems. In the present study, a non-destructive assay (NDA) system for the testing of nuclear material accountancy of PRIDE was designed by integrating three different NDA techniques, i.e., neutron, gamma-ray, and mass measurements. The developed neutron detection module consists of 56 3He tubes and 16 AMPTEK A111 signal processing circuits. The amplifiers were matched in terms of the gain and showed good uniformity after a gain-matching procedure (%RSD=0.37%). The axial and the radial efficiency distributions within the cavity were then measured using a 252Cf neutron source and were compared with the MCNPX calculation results. The measured efficiency distributions showed excellent agreement with the calculations, which confirmed the accuracy of the MCNPX model of the system.

Seo, Hee; Park, Se-Hwan; Won, Byung-Hee; Ahn, Seong-Kyu; Shin, Hee-Sung; Na, Sang-Ho; Song, Dae-Yong; Kim, Ho-Dong; Lee, Seung Kyu

2013-12-01

55

Gamma ray scanner systems for nondestructive assay of heterogeneous waste barrels  

SciTech Connect

Traditional gamma safeguards measurements have usually been performed using a segmented gamma scanning (SGS) system. The accuracy of this technique relies on the assumption that the sample matrix and the activity are both uniform for a segment. Waste barrels are often highly heterogeneous, span a wide range of composition and matrix type. The primary sources of error are all directly or indirectly related to a non-uniform measurement response associated with unknown radioactive source spatial distribution and heterogeneity of the matrix. These errors can be significantly reduced by some imaging techniques that measure exact spatial locations of sources and attenuation maps. In this paper we describe a joint R&D effort between the Lawrence Livermore National Laboratory (LLNL) and the Institute of Nuclear Techniques (INT) of the Technical University, Budapest, to compare results obtained by two different gamma-ray nondestructive assay (NDA) systems used for imaging waste barrels. The basic principles are the same, but the approaches are different. Key factors to judge the adequacy of a method are the detection limit and the accuracy. Test drums representing waste to be measured are used to determine basic parameters of these techniques.

Martz, H.E.; Decman, B.J.; Roberson, G.P.; Levai, F.

1997-03-25

56

Radiometric holdup measurements: Differential mass holdup of americium and plutonium oxides during preparation of traceable non-destructive assay standards  

Microsoft Academic Search

Summary  Traceable non-destructive assay standards containing mixtures of well characterized americium and plutonium oxides were prepared by blending weighed quantities with a diatomaceous earth matrix and encapsulating in welded zirconium cylinders. Am and Pu retained in fabrication process materials (e.g., emptied blend bottles), termed holdup, was quantified by gamma-spectroscopy in order to accurately state the total nuclear material content of the

S. L. Mecklenburg; G. K. Becker

2005-01-01

57

Feasability of using a graphite slowing-down-time spectrometer in the nondestructive assay of nuclear materials  

Microsoft Academic Search

A slowing-down-time spectrometer (SDTS), constructed for the study of nondestructive assay of fissile nuclear materials, is in its early stages of operation at the Nuclear Engineering Teaching Laboratory of the University of Texas at Austin. The spectrometer is made of a 101×105×122cm3 graphite rectangular parallelepiped and is based on injecting pulses of 14MeV neutrons into the pile. The neutron source

Ayman Ibrahim Hawari; Bernard W. Wehring; Horia R. Radulescu; Naeem M. Abdurrahman

1999-01-01

58

Non-destructive assay of drum package radioactive wastes utilizing tomographic gamma scanning  

SciTech Connect

A methodology for nondestructive assay of drum packaged radioactive waste materials is investigated using Emission Computed Tomography procedures. A requirement of this method is accurate gamma attenuation correction. This is accomplished by the use of a constant density distribution for the drum content, thereby requiring the need for a homogeneous medium. The current predominant NDA technique is the use of the Segmented Gamma Scanner. Tomographic Gamma Scanning improves upon this method by providing a low resolution three-dimensional image of the source distribution, yielding both spatial and activity information. Reconstruction of the source distribution is accomplished by utilization of algebraic techniques with a nine by six voxel model with detector information gathered over scanning intervals of ninety degrees. Construction of a linear system to describe the scenario was accomplished using a point-source response function methodology, where a 54 {times} 120 matrix contained the projected detector responses for each source-detector geometry. Entries in this matrix were calculated using the point-kernal shielding code QAD-CGGP. Validation was performed using the MCNP photon transport code. Solutions to the linear system were determined using the Non-Negative Least Squares (NNLS) algorithm and the LSMOD algorithm. A series of four scans were performed, each reconstructing the source distribution of a mock-up waste package containing a single 73 mCi {sup 137}Cs point source. For each scan, the source was located in a different location. Results of the reconstruction routines accurately predict the location and activity of the source. The range of activity calculated using the NNLS routine is 0.2681 mCi with an average value of 77.7995 mCi. The range of values calculated using LSMOD is 5.1843 mCi with an average of 72.8018 mCi.

Ausbrooks, K.L.

1996-05-01

59

Performance Demonstration Program Plan for Nondestructive Assay of Drummed Wastes for the TRU Waste Characterization Program  

SciTech Connect

The Performance Demonstration Program (PDP) for nondestructive assay (NDA) consists of a series of tests to evaluate the capability for NDA of transuranic (TRU) waste throughout the Department of Energy (DOE) complex. Each test is termed a PDP cycle. These evaluation cycles provide an objective measure of the reliability of measurements obtained from NDA systems used to characterize the radiological constituents of TRU waste. The primary documents governing the conduct of the PDP are the Waste Acceptance Criteria for the Waste Isolation Pilot Plant (WAC; DOE 1999a) and the Quality Assurance Program Document (QAPD; DOE 1999b). The WAC requires participation in the PDP; the PDP must comply with the QAPD and the WAC. The WAC contains technical and quality requirements for acceptable NDA. This plan implements the general requirements of the QAPD and applicable requirements of the WAC for the NDA PDP. Measurement facilities demonstrate acceptable performance by the successful testing of simulated waste containers according to the criteria set by this PDP Plan. Comparison among DOE measurement groups and commercial assay services is achieved by comparing the results of measurements on similar simulated waste containers reported by the different measurement facilities. These tests are used as an independent means to assess the performance of measurement groups regarding compliance with established quality assurance objectives (QAO's). Measurement facilities must analyze the simulated waste containers using the same procedures used for normal waste characterization activities. For the drummed waste PDP, a simulated waste container consists of a 55-gallon matrix drum emplaced with radioactive standards and fabricated matrix inserts. These PDP sample components are distributed to the participating measurement facilities that have been designated and authorized by the Carlsbad Field Office (CBFO). The NDA Drum PDP materials are stored at these sites under secure conditions to protect them from loss, tampering, or accidental damage. Using removable PDP radioactive standards, isotopic activities in the simulated waste containers are varied to the extent possible over the range of concentrations anticipated in actual waste characterization situations. Manufactured matrices simulate expected waste matrix conditions and provide acceptable consistency in the sample preparation process at each measurement facility. Analyses that are required by the Waste Isolation Pilot Plant (WIPP) to demonstrate compliance with various regulatory requirements and that are included in the PDP may only be performed by measurement facilities that demonstrate acceptable performance in the PDP. These analyses are referred to as WIPP analyses, and the wastes on which they are performed are referred to as WIPP wastes in this document.

DOE Carlsbad Field Office

2001-04-06

60

APNEA/WIT system nondestructive assay capability evaluation plan for select accessibly stored INEL RWMC waste forms  

SciTech Connect

Bio-Imaging Research Inc. (BIR) and Lockheed Martin Speciality Components (LMSC) are engaged in a Program Research and Development Agreement and a Rapid Commercialization Initiative with the Department of Energy, EM-50. The agreement required BIR and LMSC to develop a data interpretation method that merges nondestructive assay and nondestructive examination (NDA/NDE) data and information sufficient to establish compliance with applicable National TRU Program (Program) waste characterization requirements and associated quality assurance performance criteria. This effort required an objective demonstration of the BIR and LMSC waste characterization systems in their standalone and integrated configurations. The goal of the test plan is to provide a mechanism from which evidence can be derived to substantiate nondestructive assay capability and utility statement for the BIT and LMSC systems. The plan must provide for the acquisition, compilation, and reporting of performance data thereby allowing external independent agencies a basis for an objective evaluation of the standalone BIR and LMSC measurement systems, WIT and APNEA respectively, as well as an expected performance resulting from appropriate integration of the two systems. The evaluation is to be structured such that a statement regarding select INEL RWMC waste forms can be made in terms of compliance with applicable Program requirements and criteria.

Becker, G.K.

1997-01-01

61

Performance Demonstration Program Plan for Nondestructive Assay of Boxed Wastes for the TRU Waste Characterization Program  

SciTech Connect

The Performance Demonstration Program (PDP) for nondestructive assay (NDA) consists of a series of tests to evaluate the capability for NDA of transuranic (TRU) waste throughout the Department of Energy (DOE) complex. Each test is termed a PDP cycle. These evaluation cycles provide an objective measure of the reliability of measurements obtained from NDA systems used to characterize the radiological constituents of TRU waste. The primary documents governing the conduct of the PDP are the Waste Acceptance Criteria for the Waste Isolation Pilot Plant (WAC; DOE 1999a) and the Quality Assurance Program Document (QAPD; DOE 1999b). The WAC requires participation in the PDP; the PDP must comply with the QAPD and the WAC. The WAC contains technical and quality requirements for acceptable NDA. This plan implements the general requirements of the QAPD and applicable requirements of the WAC for the NDA PDP for boxed waste assay systems. Measurement facilities demonstrate acceptable performance by the successful testing of simulated waste containers according to the criteria set by this PDP Plan. Comparison among DOE measurement groups and commercial assay services is achieved by comparing the results of measurements on similar simulated waste containers reported by the different measurement facilities. These tests are used as an independent means to assess the performance of measurement groups regarding compliance with established quality assurance objectives (QAO’s). Measurement facilities must analyze the simulated waste containers using the same procedures used for normal waste characterization activities. For the boxed waste PDP, a simulated waste container consists of a modified standard waste box (SWB) emplaced with radioactive standards and fabricated matrix inserts. An SWB is a waste box with ends designed specifically to fit the TRUPACT-II shipping container. SWB’s will be used to package a substantial volume of the TRU waste for disposal. These PDP sample components are distributed to the participating measurement facilities that have been designated and authorized by the Carlsbad Field Office (CBFO). The NDA Box PDP materials are stored at these sites under secure conditions to protect them from loss, tampering, or accidental damage. Using removable PDP radioactive standards, isotopic activities in the simulated waste containers are varied to the extent possible over the range of concentrations anticipated in actual waste characterization situations. Manufactured matrices simulate expected waste matrix configurations and provide acceptable consistency in the sample preparation process at each measurement facility. Analyses that are required by the Waste Isolation Pilot Plant (WIPP) to demonstrate compliance with various regulatory requirements and that are included in the PDP may only be performed by measurement facilities that demonstrate acceptable performance in the PDP. These analyses are referred to as WIPP analyses, and the wastes on which they are performed are referred to as WIPP wastes in this document.

Carlsbad Field Office

2001-01-31

62

Performance Demonstration Program Plan for Nondestructive Assay of Drummed Wastes for the TRU Waste Characterization Program  

SciTech Connect

The Performance Demonstration Program (PDP) for Nondestructive Assay (NDA) is a test program designed to yield data on measurement system capability to characterize drummed transuranic (TRU) waste generated throughout the Department of Energy (DOE) complex. The tests are conducted periodically and provide a mechanism for the independent and objective assessment of NDA system performance and capability relative to the radiological characterization objectives and criteria of the Office of Characterization and Transportation (OCT). The primary documents requiring an NDA PDP are the Waste Acceptance Criteria for the Waste Isolation Pilot Plant (WAC), which requires annual characterization facility participation in the PDP, and the Quality Assurance Program Document (QAPD). This NDA PDP implements the general requirements of the QAPD and applicable requirements of the WAC. Measurement facilities must demonstrate acceptable radiological characterization performance through measurement of test samples comprised of pre-specified PDP matrix drum/radioactive source configurations. Measurement facilities are required to analyze the NDA PDP drum samples using the same procedures approved and implemented for routine operational waste characterization activities. The test samples provide an independent means to assess NDA measurement system performance and compliance per criteria delineated in the NDA PDP Plan. General inter-comparison of NDA measurement system performance among DOE measurement facilities and commercial NDA services can also be evaluated using measurement results on similar NDA PDP test samples. A PDP test sample consists of a 55-gallon matrix drum containing a waste matrix type representative of a particular category of the DOE waste inventory and nuclear material standards of known radionuclide and isotopic composition typical of DOE radioactive material. The PDP sample components are made available to participating measurement facilities as designated by the Carlsbad Field Office (CBFO). The nuclear material type, mass and associated alpha activity of the NDA PDP radioactive standard sets have been specified and fabricated to allow assembly of PDP samples that simulate TRU alpha activity concentrations, radionuclidic/isotopic distributions and physical forms typical of the DOE TRU waste inventory. The PDP matrix drum waste matrix types were derived from an evaluation of information contained in the Transuranic Waste Baseline Inventory Report (TWBIR) to ensure representation of prevalent waste types and their associated matrix characteristics in NDA PDP testing. NDA drum analyses required by the Waste Isolation Pilot Plant (WIPP) may only be performed by measurement facilities that comply with the performance criteria as set forth in the NDA PDP Plan. In this document, these analyses are referred to as WIPP analyses, and the wastes on which they are performed are referred to as WIPP wastes.

Carlsbad Field Office

2005-08-03

63

Characterizing and improving passive-active shufflers for assays of 208-Liter waste drums  

SciTech Connect

A passive and active neutron shuffler for 208-L waste drums has been used to perform over 1500 active and 500 passive measurements on uranium and plutonium samples in 28 different matrices. The shuffler is now better characterized and improvements have been implemented or suggested. An improved correction for the effects of the matrix material was devised from flux-monitor responses. The most important cause of inaccuracies in assays is a localized instead of a uniform distribution of fissile material in a drum; a technique for deducing the distribution from the assay data and then applying a correction is suggested and will be developed further. A technique is given to detect excessive amounts of moderator that could make hundreds of grams of {sup 235}U assay as zero grams. Sensitivities (minimum detectable masses) for {sup 235}U with active assays and for {sup 240}Pu{sub eff} with passive assays are presented and the effects of moderators and absorbers on sensitivities noted.

Rinard, P.M.; Adams, E.L.; Menlove, H.O.; Sprinkle, J.K. Jr.

1992-01-01

64

Characterizing and improving passive-active shufflers for assays of 208-Liter waste drums  

SciTech Connect

A passive and active neutron shuffler for 208-L waste drums has been used to perform over 1500 active and 500 passive measurements on uranium and plutonium samples in 28 different matrices. The shuffler is now better characterized and improvements have been implemented or suggested. An improved correction for the effects of the matrix material was devised from flux-monitor responses. The most important cause of inaccuracies in assays is a localized instead of a uniform distribution of fissile material in a drum; a technique for deducing the distribution from the assay data and then applying a correction is suggested and will be developed further. A technique is given to detect excessive amounts of moderator that could make hundreds of grams of {sup 235}U assay as zero grams. Sensitivities (minimum detectable masses) for {sup 235}U with active assays and for {sup 240}Pu{sub eff} with passive assays are presented and the effects of moderators and absorbers on sensitivities noted.

Rinard, P.M.; Adams, E.L.; Menlove, H.O.; Sprinkle, J.K. Jr.

1992-06-01

65

The use of calibration standards and the correction for sample self-attenuation in gamma-ray nondestructive assay  

SciTech Connect

The efficient use of appropriate calibration standards and the correction for the attenuation of the gamma rays within an assay sample by the sample itself are two important and closely related subjects in gamma-ray nondestructive assay. Much research relating to those subjects has been done in the Nuclear Safeguards Research and Development program at the Los Alamos National Laboratory since 1970. This report brings together most of the significant results of that research. Also discussed are the nature of appropriate calibration standards and the necessary conditions on the composition, size, and shape of the samples to allow accurate assays. Procedures for determining the correction for the sample self-attenuation are described at length including both general principles and several specific useful cases. The most useful concept is that knowing the linear attenuation coefficient of the sample (which can usually be determined) and the size and shape of the sample and its position relative to the detector permits the computation of the correction factor for the self-attenuation. A major objective of the report is to explain how the procedures for determining the self-attenuation correction factor can be applied so that calibration standards can be entirely appropriate without being particularly similar, either physically or chemically, to the items to be assayed. This permits minimization of the number of standards required to assay items with a wide range of size, shape, and chemical composition.

Parker, J.L.

1986-11-01

66

Use of calibration standards and the correction for sample self-attenuation in gamma-ray nondestructive assay  

SciTech Connect

The efficient use of appropriate calibration standards and the correction for the attenuation of the gamma rays within an assay sample by the sample itself are two important and closely related subjects in gamma-ray nondestructive assay. Much research relating to those subjects has been done in the Nuclear Safeguards Research and Development program at the Los Alamos National Laboratory since 1970. This report brings together most of the significant results of that research. Also discussed are the nature of appropriate calibration standards and the necessary conditions on the composition, size, and shape of the samples to allow accurate assays. Procedures for determining the correction for the sample self-attenuation are described at length including both general principles and several specific useful cases. The most useful concept is that knowing the linear attenuation coefficient of the sample (which can usually be determined) and the size and shape of the sample and its position relative to the detector permits the computation of the correction factor for the self-attenuation. A major objective of the report is to explain how the procedures for determining the self-attenuation correction factor can be applied so that calibration standards can be entirely appropriate without being particularly similar, either physically or chemically, to the items to be assayed. This permits minimization of the number of standards required to assay items with a wide range of size, shape, and chemical composition. 17 references, 18 figures, 2 tables.

Parker, J.L.

1984-08-01

67

An integrated approach for determining plutonium mass in spent fuel assemblies with nondestructive assay  

SciTech Connect

There are a variety of reasons for quantifying plutonium (Pu) in spent fuel. Below, five motivations are listed: (1) To verify the Pu content of spent fuel without depending on unverified information from the facility, as requested by the IAEA ('independent verification'). New spent fuel measurement techniques have the potential to allow the IAEA to recover continuity of knowledge and to better detect diversion. (2) To assure regulators that all of the nuclear material of interest leaving a nuclear facility actually arrives at another nuclear facility ('shipper/receiver'). Given the large stockpile of nuclear fuel at reactor sites around the world, it is clear that in the coming decades, spent fuel will need to be moved to either reprocessing facilities or storage sites. Safeguarding this transportation is of significant interest. (3) To quantify the Pu in spent fuel that is not considered 'self-protecting.' Fuel is considered self-protecting by some regulatory bodies when the dose that the fuel emits is above a given level. If the fuel is not self-protecting, then the Pu content of the fuel needs to be determined and the Pu mass recorded in the facility's accounting system. This subject area is of particular interest to facilities that have research-reactor spent fuel or old light-water reactor (LWR) fuel. It is also of interest to regulators considering changing the level at which fuel is considered self-protecting. (4) To determine the input accountability value at an electrochemical processing facility. It is not expected that an electrochemical reprocessing facility will have an input accountability tank, as is typical in an aqueous reprocessing facility. As such, one possible means of determining the input accountability value is to measure the Pu content in the spent fuel that arrives at the facility. (5) To fully understand the composition of the fuel in order to efficiently and safely pack spent fuel into a long-term repository. The NDA of spent fuel can be part of a system that cost-effectively meets the burnup credit needs of a repository. Behind each of these reasons is a regulatory structure with MC&A requirements. In the case of the IAEA, the accountable quantity is elemental plutonium. The material in spent fuel (fissile isotopes, fission products, etc.) emits signatures that provide information about the content and history of the fuel. A variety of nondestructive assay (NDA) techniques are available to quantify these signatures. The effort presented in this paper is investigation of the capabilities of 12 NDA techniques. For these 12, none is conceptually capable of independently determining the Pu content in a spent fuel assembly while at the same time being able to detect the diversion of a significant quantity of rods. For this reason the authors are investigating the capability of 12 NDA techniques with the end goal of integrating a few techniques together into a system that is capable of measuring Pu mass in an assembly. The work described here is the beginning of what is anticipated to be a five year effort: (1) two years of modeling to select the best technologies, (2) one year fabricating instruments and (3) two years measuring spent fuel. This paper describes the first two years of this work. In order to cost effectively and robustly model the performance of the 12 NDA techniques, an 'assembly library' was created. The library contains the following: (a) A diverse range of PWR spent fuel assemblies (burnup, enrichment, cooling time) similar to that which exists in spent pools today and in the future. (b) Diversion scenarios that capture a range of possible rod removal options. (c) The spatial and isotopic detail needed to accurately quantify the capability of all the NDA techniques so as to enable integration. It is our intention to make this library available to other researchers in the field for inter-comparison purposes. The performance of each instrument will be quantified for the full assembly library for measurements in three different media: air, water and borated water. The 12 NDA te

Swinhoe, Martyn T [Los Alamos National Laboratory; Tobin, Stephen J [Los Alamos National Laboratory; Fensin, Mike L [Los Alamos National Laboratory; Menlove, Howard O [Los Alamos National Laboratory

2009-01-01

68

Quality Assurance Objectives for Nondestructive Assay with the Residues Segmented Gamma Scan Assay System at the Plutonium Finishing Plant (PFP)  

SciTech Connect

The PFP facility utilizes a Segmented Gamma Scanner Assay System (SGSAS) to perform assays on cans of ash for WIPP characterization measurements. This report documents the conformance of SGSAS to the precision and accuracy radioassay QAOs, and reports the minimum detectable concentration (MDC). The QAO measurement runs supplied in this document were for a billet can geometry. The billet cans containing stabilized residues will be loaded into pipe overpack containers (POC) for shipment to WIPP. The measurements were performed in March, 2001 following a system reconfiguration which occurred on October 27, 2000. The actual system recalibration was performed in March 2001. The new calibration will be used for all assay data collected after October 27, 2000. No parameter changes have been made and the system has been in measurement control during this period of time. The WIPP-WAC defines four nominal test levels for NDA, which are in alpha curies and grams of weapons grade (WG) Pu. Due to intended utilization of the SGSAS system for the materials mentioned above, it is presently only being qualified for the two highest QAO ranges. The sources used for the QAO measurement are the WPP NDA Performance Demonstration Project working reference materials. This report documents the analysis of test data for the SGSAS system at the nominal 10 gram and 160 gram levels. The MDC was determined using a billet can filled with diatomaceous earth but no plutonium present. Since the system is not being qualified for TRU vs low-level waste (LLW) sorting the MDC will primarily provide verification that the detection level for the system is well below the QAO ranges for which the system is being qualified. The MDC reflects the best sensitivity for a particular assay system and specific assay conditions (i.e. count time, sample configuration) when no added radioactivity is present. As such, no radioactive sources were required for the MDC determination. As with the accuracy and precision QAOs, the MDC is valid for the billet cans.

WESTSIK, G.A.

2001-04-06

69

Technical note: The calibration of {sup 90}Y-labeled SIR-Spheresusing a nondestructive spectroscopic assay  

SciTech Connect

{sup 90}Y-labeled SIR-Spheres are currently used to treat patients with hepatic metastases secondary to colorectal adenocarcinoma. In general, the prescribed activity is based on empirical data collected during clinical trials. The activity of the source vial is labeled by the manufacturer as 3.0 GBq{+-}10% and is not independently verified by the end user. This technical note shows that the results of a nondestructive spectroscopic assay of a SIR-Spheressample was 26% higher than the activity stated by the manufacturer. This difference should not impact the current empirical prescription method but may be problematic for patient-specific dosimetry applications, such as image-based dosimetry.

Selwyn, R.; Micka, J.; DeWerd, L.; Nickles, R.; Thomadsen, B. [Department of Medical Physics, University of Wisconsin, Madison, Wisconsin 53706 (United States)

2008-04-15

70

Nondestructive Assay Measurements Using the RPI Lead Slowing-Down Spectrometer  

E-print Network

background from the Pu-Be source and the intense interrogation neutron flux, the LSDS system was able and models are well suited to simulate the assay. An absolute calibration technique of the LSDS, which

Danon, Yaron

71

Application of active and passive neutron non destructive assay methods to concrete radioactive waste drums  

NASA Astrophysics Data System (ADS)

This paper deals with the application of non-destructive neutron measurement methods to control and characterize 200 l radioactive waste drums filled with a concrete matrix. Due to its composition, and particularly to hydrogen, concrete penalizes the use of such methods to quantify uranium (U) and plutonium (Pu) components, which are mainly responsible of the ?-activity of the waste. The determination of the alpha activity is the main objective of neutron measurements, in view to verify acceptance criteria in surface storage. Calibration experiments of the Active Neutron Interrogation (ANI) method lead to Detection Limit Masses (DLM) of about 1 mg of 239Pu eff in the total counting mode, and of about 10 mg of 239Pu eff in the coincidence counting mode, in case of a homogeneous Pu source and measurement times between one and two hours. Monte Carlo calculation results show a very satisfactory agreement between experimental values and calculated ones. Results of the application of passive and active neutron methods to control two real drums are presented in the last part of the paper. They show a good agreement between measured data and values declared by the waste producers. The main difficulties that had to be overcome are the low neutron signal in passive and active coincidence counting modes due to concrete, the analysis of the passive neutron signal in presence of 244Cm in the drum, which is a strong spontaneous fission neutron emitter, the variation of the active background with the concrete composition, and the analysis of the active prompt neutron signal due to the simultaneous presence of U and Pu in the drums.

Jallu, F.; Passard, C.; Brackx, E.

2011-09-01

72

Determining plutonium mass in spent fuel with non-destructive assay techniques - NGSU research overview and update on 6 NDA techniques  

SciTech Connect

This poster is one of two complementary posters. The Next Generation Safeguards Initiative (NGSI) of the U.S. DOE has initiated a multi-lab/university collaboration to quantify the plutonium (Pu) mass in, and detect the diversion of pins from, spent nuclear fuel assemblies with non-destructive assay (NDA). This research effort has the goal of quantifying the capability of 14 NDA techniques as well as training a future generation of safeguards practitioners. By November of 2010, we will be 1.5 years into the first phase (2.5 years) of work. This first phase involves primarily Monte Carlo modelling while the second phase (also 2.5 years) will focus on experimental work. The goal of phase one is to quantify the detection capability of the various techniques for the benefit of safeguard technology developers, regulators, and policy makers as well as to determine what integrated techniques merit experimental work, We are considering a wide range of possible technologies since our research horizon is longer term than the focus of most regulator bodies. The capability of all of the NDA techniques will be determined for a library of 64 17 x 17 PWR assemblies [burnups (15, 30, 45, 60 GWd/tU), initial enrichments (2, 3, 4, 5%) and cooling times (1, 5, 20, 80 years)]. The burnup and cooling time were simulated with each fuel pin being comprised of four radial regions. In this paper an overview of the purpose will be given as well as a technical update on the following 6 neutron techniques: {sup 252}Cf Interrogation with Prompt Neutron Detection, Delayed Neutrons, Differential Die-Away, Differential Die-Away Self-Interrogation, Passive Neutron Albedo Reactivity, Self-Integration Neutron Resonance Densitometry. The technical update will quantify the anticipated performance of each technique for the 64 assemblies of the spent fuel library.

Tobin, Stephen J [Los Alamos National Laboratory; Conlin, Jeremy L [Los Alamos National Laboratory; Evans, Louise G [Los Alamos National Laboratory; Hu, Kianwei [Los Alamos National Laboratory; Blanc, P C [Los Alamos National Laboratory; Lafleur, Am [Los Alamos National Laboratory; Menlove, H O [Los Alamos National Laboratory; Schear, M A [Los Alamos National Laboratory; Swinhoe, M T [Los Alamos National Laboratory; Croft, S [Los Alamos National Laboratory; Fensin, M L [Los Alamos National Laboratory; Freeman, C R [Los Alamos National Laboratory; Koehler, W E [Los Alamos National Laboratory; Mozin, V [Los Alamos National Laboratory; Sandoval, N P [Los Alamos National Laboratory; Lee, T H [KAERI; Cambell, L W [PNNL; Cheatham, J R [ORNL; Gesh, C J [PNNL; Hunt, A [IDAHO STATE UNIV; Ludewigt, B A [LBNL; Smith, L E [PNNL; Sterbentz, J [INL

2010-09-15

73

Feasability of using a graphite slowing-down-time spectrometer in the nondestructive assay of nuclear materials  

NASA Astrophysics Data System (ADS)

A slowing-down-time spectrometer (SDTS), constructed for the study of nondestructive assay of fissile nuclear materials, is in its early stages of operation at the Nuclear Engineering Teaching Laboratory of the University of Texas at Austin. The spectrometer is made of a 101×105×122 cm 3 graphite rectangular parallelepiped and is based on injecting pulses of 14 MeV neutrons into the pile. The neutron source is a Texas Nuclear Corporation neutron generator that produces neutrons via the D-T reaction. Measurements and calculations have been conducted to study the time behavior of the neutrons and the assay capabilities of this spectrometer. A 3He detector covered with 0.8 mm of Cd was used to perform neutron die-away measurements in the graphite. A 4He detector was used to perform an assay of a fuel pin containing 13% by mass 239Pu. The calculations were made using the MCNP4B code, and a realistic 3-D mock-up of the experiment. Good agreement is found to exist between the measured time spectra and the ones predicted from the calculations. This included the experimental observation of a predicted rapid fall-off in the die-away spectrum due to the existence of the cadmium cover. Therefore, the time-energy coupling that is expected to hold in a SDTS is experimentally verified. In addition, the calculations and the measurements indicate that the interrogation of fissile materials is possible using a graphite SDTS. This is clear in the measured and calculated time signatures for the 239Pu sample, which include structure that reflects the two resonance groups and the 0.3 eV resonance peak observed in the 239Pu fission cross section.

Ibrahim Hawari, Ayman; Wehring, Bernard W.; Radulescu, Horia R.; Abdurrahman, Naeem M.

1999-02-01

74

Applications of Monte Carlo simulations of thermalization processes to the nondestructive assay of graphite  

SciTech Connect

This work originated because of the need to measure (in situ and nondestructively) the degree of purity of the graphite of the Swiss critical facility Proteus. The comparison between measured and calculated values of the decay constant of a pulse of neutrons {lambda} was the chosen technique. The decay constant (in the absence of fissile materials) depends, mainly, on the purity of the graphite (via the absorption process) and leakage. The leakage factor depends on the thermalization process and the geometry of the system. Because it is very difficult to calculate in complex geometries like the Proteus cavity, Monte Carlo simulations of the behavior of a pulse of neutrons were made with the MCNP code. Despite all the sophistication of MCNP, the ultimate accuracy of the calculations is dependent upon the quality of the nuclear data that describe the thermalization process in the graphite. A recent review of these data shows that very little has changed in the last 30 yr in the ENDF/B evaluation of the double-differential scattering cross section. The author decided then to benchmark the current state of the art to compute kinetics experiments in graphite (the MCNP code and the ENDF/B-VI cross-section set) against experimental data and other theoretical results for the analysis of the thermalization problem. Two classes of experiments were analyzed: (1) neutron wave propagation, where the observable is the complex relaxation length, and (2) pulsed neutron decay, where {lambda} is measured as a function of the dimensions of the graphite. Once the bias of the calculational technique was known, it was used to calculate the neutron decay constant of the Proteus cavity as a function of the {sup 10}B equivalent impurity concentration. A comparison with pulsed neutron decay experiments made at Proteus allowed the determination of the degree of purity of the graphite. In this last part, he took full advantage of the sophistication of the MCNP code to model many details of the facility quite accurately including room return effects.

Difilippo, F.C.

1999-10-01

75

Application of nondestructive assay technology in Oak Ridge National Laboratory's waste management program  

SciTech Connect

Waste characterization is the process whereby physical properties and chemical composition of waste are determined. Waste characterization is an important element of a waste certification program in that it provides information which is necessary to certify that waste meets the acceptance criteria for storage, treatment, or disposal. Department of Energy (DOE) Order 5820.2A and WIPP-DOE-069 list and describe the germane waste form, package, and container criteria for the storage of both solid low-level waste (SLLW) and transuranic (TRU) waste, including chemical composition and compatibility, hazardous material content, fissile material content, equivalent alpha activity, thermal heat output, and absence of free liquids, explosives, and compressed gases. At the Oak Ridge National Laboratory (ORNL), the responsibility for waste characterization begins with the individual(s) who generate the waste. The generator must be able to document the type and estimate the quantity of various materials which have been placed into the waste container. Analyses of process flow sheets and a statistically valid sampling program can provide much of the required information as well as a documented level of confidence in the acquired data. A program is being instituted in which the major generator facilities perform radionuclide assay of small packets of waste prior to being placed into a waste drum. 10 refs., 1 fig., 1 tab.

Schultz, F.J.; Smith, M.A.; Brandenburg, R.W.; Caylor, B.A.; Coffey, D.E.; Hensley, D.C.; Phoenix, L.B.

1990-01-01

76

Advanced Non-Destructive Assay Systems and Special Instrumentation Requirements for Spent Nuclear Fuel Recycling Facilities  

SciTech Connect

The safe and efficient operation of the next generation of Spent Nuclear Fuel (SNF) recycling / reprocessing facilities is dependent upon the availability of high performance real time Non- Destructive Assay (NDA) systems at key in-line points. A diverse variety of such special instrument systems have been developed and commissioned at reprocessing plants worldwide over the past fifty years.. The measurement purpose, technique and plant performance for selected key systems have been reviewed. Obsolescence issues and areas for development are identified in the context of the measurements needs of future recycling facilities and their associated waste treatment plants. Areas of concern include (i) Materials Accountancy and Safeguards, (ii) Head End process control and feed envelope verification, (iii) Real-time monitoring at the Product Finishing Stages, (iv) Criticality safety and (v) Radioactive waste characterization. Common characteristics of the traditional NDA systems in historical recycling facilities are (i) In-house development of bespoke instruments resulting in equipment that if often unique to a given facility and generally not commercially available, (ii) Use of 'novel' techniques - not widely deployed in other applications, (iii) Design features that are tailored to the specific plant requirements of the facility operator, (iv) Systems and software implementation that was not always carried out to modern industry standards and (v) A tendency to be overly complex - refined by on-plant operational usage and experience. Although these systems were 'validated in use' and are generally fit for purpose, there are a number of potential problems in transferring technology that was developed ten or more years ago to the new build SNF recycling facilities of the future. These issues include (i) Obsolescence of components - particularly with respect to computer hardware and data acquisition electronics, (ii) Availability of Intellectual Property and design drawings and documentation (iii) Lack of compatibility with modern computers, software, data transfer networks, digital protocols and electrical code standards, (iv) Non-compliance with current and future mandatory standards and regulations for nuclear facilities (v) Design focused on measurement and control points that may be specific to the facility process (vi) Lack of utilization of recent technological advances where better performing, less complex and more cost-effective options are now available. Key radiometric measurement drivers and control points for future recycling facilities have been determined and a review of the adequacy of existing instrumentation has been performed. Areas where recent technology improvements may be more effectively deployed and future technology development may be appropriate are identified. (author)

Simpson, A.P.; Clapham, M.J.; Swinson, B. [Pajarito Scientific Corp., Santa Fe, NM (United States)

2008-07-01

77

Passive water-lipid peptide translocators with conformational switches: From single-molecule probe to cellular assay  

PubMed Central

Peptide design for unassisted passive water/lipid translocation remains a challenge, notwithstanding its importance for drug delivery. We introduce a design paradigm based on conformational switches operating as passive translocation vehicles. The interfacial behavior of the molecular prototype, probed in single-molecule AFM experiments, reveals a near-barrierless translocation. The associated free-energy agrees with mesoscopic measurements, and the in vitro behavior is quantitatively reproduced in cellular assays. The prototypes herald the advent of novel nano-biomaterials for passive translocation. PMID:18044863

Fernandez, Ariel; Crespo, Alejandro; Blau, Axel

2008-01-01

78

Determining Plutonium Mass in Spent Fuel with Nondestructive Assay Techniques -- Preliminary Modeling Results Emphasizing Integration among Techniques  

SciTech Connect

There are a variety of motivations for quantifying Pu in spent (used) fuel assemblies by means of nondestructive assay (NDA) including the following: strengthen the capabilities of the International Atomic Energy Agencies to safeguards nuclear facilities, quantifying shipper/receiver difference, determining the input accountability value at reprocessing facilities and providing quantitative input to burnup credit determination for repositories. For the purpose of determining the Pu mass in spent fuel assemblies, twelve NDA techniques were identified that provide information about the composition of an assembly. A key point motivating the present research path is the realization that none of these techniques, in isolation, is capable of both (1) quantifying the elemental Pu mass of an assembly and (2) detecting the diversion of a significant number of pins. As such, the focus of this work is determining how to best integrate 2 or 3 techniques into a system that can quantify elemental Pu and to assess how well this system can detect material diversion. Furthermore, it is important economically to down-select among the various techniques before advancing to the experimental phase. In order to achieve this dual goal of integration and down-selection, a Monte Carlo library of PWR assemblies was created and is described in another paper at Global 2009 (Fensin et al.). The research presented here emphasizes integration among techniques. An overview of a five year research plan starting in 2009 is given. Preliminary modeling results for the Monte Carlo assembly library are presented for 3 NDA techniques: Delayed Neutrons, Differential Die-Away, and Nuclear Resonance Fluorescence. As part of the focus on integration, the concept of"Pu isotopic correlation" is discussed and the role of cooling time determination.

Tobin, S. J.; Fensin, M. L.; Ludewigt, B. A.; Menlove, H. O.; Quiter, B. J.; Sandoval, N. P.; Swinhoe, M. T.; Thompson, S. J.

2009-08-03

79

Neutron and gamma-ray nondestructive examination of contact-handled transuranic waste at the ORNL TRU Waste Drum Assay Facility  

SciTech Connect

A nondestructive assay system, which includes the Neutron Assay System (NAS) and the Segmented Gamma Scanner (SGS), for the quantification of contact-handled (<200 mrem/h total radiation dose rate at contact with container) transuranic elements (CH-TRU) in bulk solid waste contained in 208-L and 114-L drums has been in operation at the Oak Ridge National Laboratory since April 1982. The NAS has been developed and demonstrated by Los Alamos National Laboratory (LANL) and the Oak Ridge National Laboratory (ORNL) for use by most US Department of Energy Defense Plant (DOE-DP) sites. More research and development is required, however, before the NAS can provide complete assay results for other than routine defense waste. To date, 525 ORNL waste drums have been assayed, with varying degrees of success. The isotopic complexity of the ORNL waste creates a correspondingly complex assay problem. The NAS and SGS assay data are presented and discussed. Neutron matrix effects, the destructive examination facility, and enriched uranium fuel-element assays are also discussed.

Schultz, F.J.; Coffey, D.E.; Norris, L.B.; Haff, K.W.

1985-03-01

80

Laser-Compton Scattered x-rays for non-destructive assay of surrogate fuel-cycle samples and imaging  

NASA Astrophysics Data System (ADS)

One of our research goals at the Idaho Accelerator Center focuses on Laser-Compton Scattering (LCS) based nuclear science applications such as non-destructively quantifying concentrations of transuranic (TRIJ) elements in a surrogate of spent nuclear fuel and imaging. Non-destructive techniques include x-ray transmission and x-ray fluorescence. Both of these can be very sensitive techniques with tunable monochromatic x-rays. We investigated quasi-monochromatic x-rays from LCS for this purpose. Four sharp ˜20 keV, ˜36.7 keV, ˜99 keV, and ˜122 keV LCS peaks were produced in four separate experiments using electron beams tuned to ˜33 MeV, -˜32 MeV, ˜37 MeV, and ˜41 MeV that were brought in collision with the Nd:YAG laser (the peak laser power was 4 GW) operating at 1064 nm, 532 nm and 266 nm wavelengths respectively. The linac was operating at 60 Hz with an electron beam pulse length of about 50 ps and a peak current of about 7 A. X-ray fluorescence (XRF) experiments were first carried out to identify elemental XRF emission from Ag, Cd, and Sn foils with thicknesses ranging from 25--500 mum, following the absorption of ˜36.7 keV LCS x-rays. The intensities of the measured Kalpha1 emission lines were then compared to the predicted Kalpha1 intensities; based on the comparison, there was an estimated deviation of up to ?10.4% between the predicted and measured Kalpha1 intensities. Next, the transmission experiments were carried out by transmitting a ˜99 keV LCS x-ray beam through Bi foils of thicknesses ranging from 50--250 mum to measure the transmission of the interrogating LCS x-ray beam. There was a relative deviation of up to ?9.4 % between the predicted and measured transmission respectively. We then focused on exploiting the Hybrid K-Edge Densitometry (HKED) technique for the purpose of quantifying the concentrations of Uranium in the surrogate of spent nuclear fuel using a ˜122 keV LCS x-ray beam. The measured concentrations deviated by about 2.87% and 11.86% between the HKED measurement procedure and the point source transmission measurement procedure respectively. Finally, experiments were carried out to demonstrate phase-contrast imaging by transmitting ˜20 keV LCS x-ray beam through fish samples. The vital organs were distinguishable in the processed radiographic image.

Naeem, Syed F.

81

A technical review of non-destructive assay research for the characterization of spent nuclear fuel assemblies being conducted under the US DOE NGSI  

SciTech Connect

There is a growing belief that expansion of nuclear energy generation will be needed in the coming decades as part of a mixed supply chain to meet global energy demand. At stake is the health of the economic engine that delivers human prosperity. As a consequence renewed interest is being paid to the safe management of spent nuclear fuel (SNF) and the plutonium it contains. In addition to being an economically valuable resource because it can be used to construct explosive devices, Pu must be placed on an inventory and handled securely. A multiinstitutional team of diverse specialists has been assembled under a project funded by the US Department of Energy (DOE) Next Generation Safeguards Initiative (NGSI) to address ways to nondestructively quantify the plutonium content of spent nuclear fuel assemblies, and to also detect the potential diversion of pins from those assemblies. Studies are underway using mostly Monte Carlo tools to assess the feasibility, individual and collective performance capability of some fourteen nondestructive assay methods. Some of the methods are familiar but are being applied in a new way against a challenging target which is being represented with a higher degree of realism in simulation space than has been done before, while other methods are novel. In this work we provide a brief review of the techniques being studied and highlight the main achievements to date. We also draw attention to the deficiencies identified in for example modeling capability and available basic nuclear data. We conclude that this is an exciting time to be working in the NDA field and that much work, both fundamental and applied, remains ahead if we are to advance the state of the practice to meet the challenges posed to domestic and international safeguards by the expansion of nuclear energy together with the emergence of alternative fuel cycles.

Croft, Stephen [Los Alamos National Laboratory; Tobin, Stephen J [Los Alamos National Laboratory

2010-12-06

82

Turkey red blood cell passive haemagglutination assay as guideline for specific prevention of tetanus in injured persons  

PubMed Central

Turkey red blood cell passive haemagglutination assays (TRBC-HA) were carried out on serum samples from 873 injured patients in order to compare individual prophylactic treatment against tetanus based on the anti-tetanus antibody levels with interventions based on anamnestic criteria. The results showed a great difference: according to the anamnesis 124 persons (14.2%) were protected, 253 (29%) were partially protected, and 496 (56.8%) were unprotected; according to the TRBC-HA assay, 479 (54.9%) were protected, 279 (32%) partially protected, and 115 (13.2%) unprotected. The efficiency of the prophylactic treatments given on the basis of the two criteria was also compared in a study of 129 injured patients who were divided in two groups: group 1 (50 patients) received 250 IU of human tetanus immunoglobulin (HTI) regardless of their tetanus immunity, and group II (79 patients) received appropriate or no treatment depending on the level of anti-tetanus antibodies determined by TRBC-HA assay. The results showed that prophylactic interventions based on the anti-tetanus antibody levels can give protection in 100% of injured patients at minimum cost and risk. PMID:3912079

Bistoni, F.; Marconi, P.; Perito, S.; Bastianini, L.; Antenucci, R.; Pitzurra, M.

1985-01-01

83

Development of a Lentivirus Vector-Based Assay for Non-Destructive Monitoring of Cell Fusion Activity  

PubMed Central

Cell-to-cell fusion can be quantified by endowing acceptor and donor cells with latent reporter genes/proteins and activators of these genes/proteins, respectively. One way to accomplish this goal is by using a bipartite lentivirus vector (LV)-based cell fusion assay system in which the cellular fusion partners are transduced with a flippase-activatable Photinus pyralis luciferase (PpLuc) expression unit (acceptor cells) or with a recombinant gene encoding FLPeNLS+, a nuclear-targeted and molecularly evolved version of flippase (donor cells). Fusion of both cell populations will lead to the FLPe-dependent generation of a functional PpLuc gene. PpLuc activity is typically measured in cell lysates, precluding consecutive analysis of one cell culture. Therefore, in this study the PpLuc-coding sequence was replaced by that of Gaussia princeps luciferase (GpLuc), a secretory protein allowing repeated analysis of the same cell culture. In myotubes the spread of FLPeNLS+ may be limited due to its nuclear localization signal (NLS) causing low signal outputs. To test this hypothesis, myoblasts were transduced with LVs encoding either FLPeNLS+ or an NLS-less version of FLPe (FLPeNLS?) and subsequently co-cultured in different ratios with myoblasts containing the FLPe-activatable GpLuc expression cassette. At different times after induction of cell-to-cell fusion the GpLuc activity in the culture medium was determined. FLPeNLS+ and FLPeNLS? both activated the latent GpLuc gene but when the percentage of FLPe-expressing myoblasts was limiting, FLPeNLS+ generally yielded slightly higher signals than FLPeNLS? while at low acceptor-to-donor cell ratios FLPeNLS? was usually superior. The ability of FLPeNLS+ to spread through myofibers and to induce reporter gene expression is thus not limited by its NLS. However, at high FLPe concentrations the presence of the NLS negatively affected reporter gene expression. In summary, a rapid and simple chemiluminescence assay for quantifying cell-to-cell fusion progression based on GpLuc has been developed. PMID:25028973

Neshati, Zeinab; Liu, Jia; Zhou, Guangqian; Schalij, Martin J.; de Vries, Antoine A. F.

2014-01-01

84

Progress and goals for INMM ASC N15 consensus standard ""Administrative practices for the determination and reporting of results of non-destructive assay measurements of nuclear material in situ for safeguards nuclear criticality safety and other purposes  

SciTech Connect

This paper will discuss the goals and progress to date on the development of INMM Accredited Standard Committee (ASC) N15 consensus standard Administrative Practices for the Determination and Reporting of Results of Non-Destructive Assay Measurements of Nuclear Material in situ for Safeguards, Nuclear Criticality Safety, and Other Purposes. This standard will define administrative practices in the areas of data generation and reporting of NDA assay of holdup deposits with consideration of the stakeholders of the reported results. These stakeholders may include nuclear material accounting and safeguards, nuclear criticality safety, waste management, health physics, facility characterization, authorization basis, radiation safety, and site licensing authorities. Stakeholder input will be solicited from interested parties and incorporated during the development of the document. Currently only one consensus standard exists that explicitly deals with NDA holdup measurements: ASTM C1455 Standard Test Method for Nondestructive Assay of Special Nuclear Material Holdup Using Gamma-Ray Spectroscopic Methods. The ASTM International standard emphasizes the activities involved in actually making measurements, and was developed by safeguards and NDA experts. This new INMM ASC N15 standard will complement the existing ASTM international standard. One of the largest driving factors for writing this new standard was the recent emphasis on in situ NDA measurements by the safeguards community due to the Defense Nuclear Facility Safety Board (DNFSB) recommendation 2007-1 on in situ NDA measurements. Specifically, DNFSB recommendation 2007-1 referenced the lack of programmatic requirements for accurate in situ measurements and the use of measurement results for compliance with safety based requirements. That being the case, this paper will also discuss the progress made on the Implementation Plan for Defense Nuclear Facilities Safety Board Recommendation 2007-1 Safety-Related In Situ Nondestructive Assay of Radioactive Materials. Some of the information that will be presented includes observations made during site visits, how information useful to all facilities using nondestructive assay to determine holdup material quantities will be disseminated, and preliminary results of a gap analysis performed on current in situ nondestructive assay holdup measurements.

Bracken, David S [Los Alamos National Laboratory; Lamb, Frank W [UNWIN CORPORATION

2009-01-01

85

Nondestructive evaluation  

SciTech Connect

Research reported in the thrust area of nondestructive evaluation includes: advanced 3-D imaging technologies; new techniques in laser ultrasonic testing; infrared computed tomography for thermal NDE of materials, structures, sources, and processes; automated defect detection for large laser optics; multistatic micropower impulse radar imaging for nondestructive evaluation; and multi-modal NDE for AVLIS pod shielding components.

Martz, H.E.

1997-02-01

86

Nondestructive evaluation  

Microsoft Academic Search

Research reported in the thrust area of nondestructive evaluation includes: advanced 3-D imaging technologies; new techniques in laser ultrasonic testing; infrared computed tomography for thermal NDE of materials, structures, sources, and processes; automated defect detection for large laser optics; multistatic micropower impulse radar imaging for nondestructive evaluation; and multi-modal NDE for AVLIS pod shielding components.

Martz

1997-01-01

87

PANWAS: A Passive/Active Neutron Waste Assay System for the Radiological Characterization of Waste Packages at the Nucleco Facility at Casaccia  

SciTech Connect

CANBERRA has recently supplied Nucleco SpA with a new Passive/Active Neutron Waste Assay System (PANWAS) for use at their waste management facility at Casaccia in Italy. The system complements two existing CANBERRA high-resolution gamma spectrometry waste assay systems. The three waste assay systems have been integrated into a combined facility for the radiological characterization of the waste managed by Nucleco in order to provide the information required to: - Determine the physical inventory of the nuclear material present for Safeguards purposes, - Segregate the waste into different categories, - Allow transportation to and storage in the final repository for the waste. This paper describes the main characteristics of the PANWAS, how it is used (in conjunction with the two gamma monitoring systems) to determine the radionuclide inventory of the waste and how the system was calibrated and characterized for use in this application. (authors)

Alvarez, E.; Wilkins, C.G. [CANBERRA Harwell Ltd., B528.10 Unit 1, Harwell International Business Centre, Didcot, Oxfordshire, OX11 OTA (United Kingdom); Croft, S.; Villani, M.F. [CANBERRA Industries, 800 Research Parkway, Meriden, Connecticut 06450 (United States); Ambrifi, A.; Simone, G. [Nucleco SpA, Strada Provinciale, Via Anguillarese 301, 00060 Roma (Italy)

2006-07-01

88

Evaluation of passivated ion implanted planar silicon detectors for the spectroscopy and assay of low energy electrons  

NASA Astrophysics Data System (ADS)

The passivated ion implanted planar silicon (IIPS) detector is, in comparison to other semiconductor charged particle detectors such as the silicon surface barrier (SSB) detector, characterised by a thin entrance window and by low leakage current and hence low electronic noise. For the detection of low energy electrons (? 200 keV) it has, therefore, the potential of superior sensitivity and energy resolution. Measurements have been made at room temperature with an IIPS and a SSB detector of similar specifications of the continuous ? - spectra from a 14C source (maximum energy: 156 keV) and of the line spectra from the conversion electrons of a 99mTc source. The sensitivity of a thin window (1.5-2.0 mg cm -2 mica) Geiger to 14C was also investigated. The leakage current, rms noise and capacitance characteristics as a function of the reverse bias voltage were studied for both semiconductor detectors. The IIPS had a sensitivity to 14C ? - detection 26% higher than the SSB and the IIPS with an added light-tight cover had a sensitivity essentially similar to the Geiger. For 119.5 keV conversion electrons, the IIPS had a FWHM of 10.6 keV whereas that for the SSB was 15.0 keV. The rms noise, capacitance and, in particular, leakage current values were lower for the IIPS.

Batten, Jonathan Robert

1989-05-01

89

Nondestructive evaluations  

SciTech Connect

This report discusses Nondestructive Evaluation (NDE) thrust area which supports initiatives that advance inspection science and technology. The goal of the NDE thrust area is to provide cutting-edge technologies that have promise of inspection tools three to five years in the future. In selecting projects, the thrust area anticipates the needs of existing and future Lawrence Livermore National Laboratory (LLNL) programs. NDE provides materials characterization inspections, finished parts, and complex objects to find flaws and fabrication defects and to determine their physical and chemical characteristics. NDE also encompasses process monitoring and control sensors and the monitoring of in-service damage. For concurrent engineering, NDE becomes a frontline technology and strongly impacts issues of certification and of life prediction and extension. In FY-92, in addition to supporting LLNL programs and the activities of nuclear weapons contractors, NDE has initiated several projects with government agencies and private industries to study aging infrastructures and to advance manufacturing processes. Examples of these projects are (1) the Aging Airplanes Inspection Program for the Federal Aviation Administration, (2) Signal Processing of Acoustic Signatures of Heart Valves for Shiley, Inc.; and (3) Turbine Blade Inspection for the Air Force, jointly with Southwest Research Institute and Garrett. In FY-92, the primary contributions of the NDE thrust area, described in this report were in fieldable chemical sensor systems, computed tomography, and laser generation and detection of ultrasonic energy.

Kulkarni, S.

1993-03-01

90

Characterization of waste drums using nonintrusive active and passive computed tomography  

SciTech Connect

We have developed a data acquisition scanner for gamma-ray nondestructive assay (NDA) active and passive computed tomography (A&PCT) along with associated computational techniques for image reconstruction, analysis, and display. We are using this scanner to acquire data sets of mock-waste drums at Lawrence Livermore National Laboratory (LLNIL). In this paper, we discuss some issues associated with gamma-ray spectroscopy assay, NDA imaging, describe the design and construction of an NDA drum scanner and report on code development for image reconstruction. We also present representative A&PCT assay results of well characterized mock-waste drums. These preliminary results suggest that A&PCT imaging can be used to produce accurate absolute assays of radioactivity in real-waste drums.

Roberson, G.P.; Martz, H.E.; Decman, D.J.; Camp, D.C.; Azevedo, S.G.; Keto, E.R.

1994-08-01

91

Noncontact nondestructive tests  

Microsoft Academic Search

Methods developed for noncontact nondestructive tests are reviewed. These tests were developed to improve the applicability of nondestructive tests, which were constrained to the use of sensors and contacts. The techniques applied involve ultrasonic waves for lasers, optical interferometry, thermography, and Compton effect x-ray analysis. The following topics are presented: holographic pattern, holographic reconstruction, source laser, technical holographic inspection methods,

M. Alvaro; F. J. Moreno; J. M. Martindebernardo; V. Cortes

1992-01-01

92

Argonne National Laboratory's Nondestructive  

E-print Network

the safe operationof advanced nuclear reactors. Argonne's World-Class Nondestructive Evaluation- of-the-art NDE equipment and glove boxes instrumented for examination of components pulled from and determine sizing. u The under sodium viewing test facility designs and tests ultrasonic/acoustic NDE systems

Kemner, Ken

93

Holographic nondestructive testing  

Microsoft Academic Search

Holographic nondestructive testing (HNDT) is a high sensitivity, full field, noncontact, optical technique for observing the changes in the surface of a part as it deforms under stress. The stress can arise from the minute application of heat, pressure, torque, or vibration. The information obtained can be used as a design aid to locate and quantify areas undergoing strain and

D. Rosenthal; J. Trolinger

1995-01-01

94

Nondestructive testing and metrology  

Microsoft Academic Search

Attention is given to holographic nondestructive testing where a force is applied to an object located between two holographic exposures. A technique for studying holographic interference fringes by calculating the resolution with a holodiagram is discussed. Holodiagrams, used for the creation and evaluation of holographic images are described with reference to diagram construction, the optimal utilization of the coherence length,

N. Abramson

1978-01-01

95

Nondestructive inspection perspectives  

NASA Technical Reports Server (NTRS)

This paper presents ideas for consideration by those concerned with commercial aircraft nondestructive inspection (NDI). The perspective is that of an individual with a background in military aircraft NDI, and important differences are indicated between the commercial NDI and military NDI activities. In particular, it is significantly more expensive to implement some new NDI technology, and therefore, in-depth cost-benifit studies for commercial users are recommended.

Froom, Douglas A.

1992-01-01

96

Nondestructive Testing Using Shearography  

Microsoft Academic Search

This article reviews shearography and its applications in nondestructive testing. Shearography is an interferometric technique\\u000a for full-field and non-contacting measurement of surface deformation (displacement or displacement derivatives). It was invented\\u000a to overcome some limitations of holographic interferometry by eliminating the reference beam, resulting in having much higher\\u000a tolerance to environmental disturbances. Consequently, shearography can be practiced in a typical industrial

MICHAEL Y. Y. HUNG

97

Nondestructive analysis and development  

NASA Technical Reports Server (NTRS)

This final report summarizes the achievements of project #4 of the NASA/UCF Cooperative Agreement from January 1990 to December 1992. The objectives of this project are to review NASA's NDE program at Kennedy Space Center (KSC) and recommend means for enhancing the present testing capabilities through the use of improved or new technologies. During the period of the project, extensive development of a reliable nondestructive, non-contact vibration technique to determine and quantify the bond condition of the thermal protection system (TPS) tiles of the Space Shuttle Orbiter was undertaken. Experimental modal analysis (EMA) is used as a non-destructive technique for the evaluation of Space Shuttle thermal protection system (TPS) tile bond integrity. Finite element (FE) models for tile systems were developed and were used to generate their vibration characteristics (i.e. natural frequencies and mode shapes). Various TPS tile assembly configurations as well as different bond conditions were analyzed. Results of finite element analyses demonstrated a drop in natural frequencies and a change in mode shapes which correlate with both size and location of disbond. Results of experimental testing of tile panels correlated with FE results and demonstrated the feasibility of EMA as a viable technique for tile bond verification. Finally, testing performed on the Space Shuttle Columbia using a laser doppler velocimeter demonstrated the application of EMA, when combined with FE modeling, as a non-contact, non-destructive bond evaluation technique.

Moslehy, Faissal A.

1993-01-01

98

Nondestructive testing with thermography  

NASA Astrophysics Data System (ADS)

Thermography is a nondestructive testing (NDT) technique based on the principle that two dissimilar materials, i.e., possessing different thermo-physical properties, would produce two distinctive thermal signatures that can be revealed by an infrared sensor, such as a thermal camera. The fields of NDT applications are expanding from classical building or electronic components monitoring to more recent ones such as inspection of artworks or composite materials. Furthermore, thermography can be conveniently used as a didactic tool for physics education in universities given that it provides the possibility of visualizing fundamental principles, such as thermal physics and mechanics among others.

Ibarra-Castanedo, Clemente; Tarpani, José Ricardo; Maldague, Xavier P. V.

2013-11-01

99

Nondestructive material characterization  

DOEpatents

A method and apparatus for nondestructive material characterization, such as identification of material flaws or defects, material thickness or uniformity and material properties such as acoustic velocity. The apparatus comprises a pulsed laser used to excite a piezoelectric (PZ) transducer, which sends acoustic waves through an acoustic coupling medium to the test material. The acoustic wave is absorbed and thereafter reflected by the test material, whereupon it impinges on the PZ transducer. The PZ transducer converts the acoustic wave to electrical impulses, which are conveyed to a monitor.

Deason, Vance A. (Idaho Falls, ID); Johnson, John A. (Idaho Falls, ID); Telschow, Kenneth L. (Idaho Falls, ID)

1991-01-01

100

Nondestructive equipment study  

NASA Technical Reports Server (NTRS)

Identification of existing nondestructive Evaluation (NDE) methods that could be used in a low Earth orbit environment; evaluation of each method with respect to the set of criteria called out in the statement of work; selection of the most promising NDE methods for further evaluation; use of selected NDE methods to test samples of pressure vessel materials in a vacuum; pressure testing of a complex monolythic pressure vessel with known flaws using acoustic emissions in a vacuum; and recommendations for further studies based on analysis and testing are covered.

1985-01-01

101

Holographic nondestructive testing  

SciTech Connect

Holographic nondestructive testing (HNDT) is a high sensitivity, full field, noncontact, optical technique for observing the changes in the surface of a part as it deforms under stress. The stress can arise from the minute application of heat, pressure, torque, or vibration. The information obtained can be used as a design aid to locate and quantify areas undergoing strain and as a quality control aid to identify structural flaws such as internal flaws or delaminations. HNDT is also used to identify and measure vibrational modes.

Rosenthal, D.; Trolinger, J. [MetroLaser, Irvine, CA (United States)

1995-12-01

102

Passive euthanasia  

Microsoft Academic Search

The idea of passive euthanasia has recently been attacked in a particularly clear and explicit way by an “Ethics Task Force” established by the European Association of Palliative Care (EAPC) in February 2001. It claims that the expression “passive euthanasia” is a contradiction in terms and hence that there can be no such thing. This paper critically assesses the main

E Garrard; S Wilkinson

2005-01-01

103

49 CFR 192.243 - Nondestructive testing.  

Code of Federal Regulations, 2013 CFR

...Nondestructive testing. (a) Nondestructive testing of welds must be performed by any process, other than...indicate defects that may affect the integrity of the weld. (b) Nondestructive testing of welds must be performed: (1) In accordance...

2013-10-01

104

49 CFR 192.243 - Nondestructive testing.  

Code of Federal Regulations, 2010 CFR

...Nondestructive testing. (a) Nondestructive testing of welds must be performed by any process, other than...indicate defects that may affect the integrity of the weld. (b) Nondestructive testing of welds must be performed: (1) In accordance...

2010-10-01

105

49 CFR 192.243 - Nondestructive testing.  

Code of Federal Regulations, 2012 CFR

...Nondestructive testing. (a) Nondestructive testing of welds must be performed by any process, other than...indicate defects that may affect the integrity of the weld. (b) Nondestructive testing of welds must be performed: (1) In accordance...

2012-10-01

106

49 CFR 192.243 - Nondestructive testing.  

Code of Federal Regulations, 2011 CFR

...Nondestructive testing. (a) Nondestructive testing of welds must be performed by any process, other than...indicate defects that may affect the integrity of the weld. (b) Nondestructive testing of welds must be performed: (1) In accordance...

2011-10-01

107

Nondestructive Test Probe  

NASA Technical Reports Server (NTRS)

Under the Aircraft Structural Integrity program, Langley Research Center invented a device to detect fatigue cracks in aluminum alloy plates. Krautkramer Branson obtained an exclusive license and commercialized a hand-held device, the "CrackFinder," an electromagnetic probe for nondestructive evaluation, used to scan aircraft skins for surface breaks. The technology involves an eddy current, which is an electrical current induced by an alternating magnetic field. The CrackFinder also employs an innovative self-nulling feature, where the device automatically recalibrates to zero so that each flaw detected produces a reading. Compared to conventional testing systems, the CrackFinder is affordable, small, simple to use, and needs no calibration.

1996-01-01

108

Calorimetric assay of minor actinides  

SciTech Connect

This paper reviews the principles of calorimetric assay and evaluates its potential application to the minor actinides (U-232-4, Am-241, Am- 243, Cm-245, Np-237). We conclude that calorimetry and high- resolution gamma-ray isotopic analysis can be used for the assay of minor actinides by adapting existing methodologies for Pu/Am-241 mixtures. In some cases, mixtures of special nuclear materials and minor actinides may require the development of new methodologies that involve a combination of destructive and nondestructive assay techniques.

Rudy, C.; Bracken, D.; Cremers, T.; Foster, L.A.; Ensslin, N.

1996-12-31

109

Assay for Lipolytic and Proteolytic Activity Using Marine Substrates.  

National Technical Information Service (NTIS)

Nondestructive assay procedures for determining microbial lipolytic and proteolytic activity on marine substrates were developed and tested with 287 isolates of bacteria, filamentous fungi, and yeasts. A definite substrate specificity was noted when the e...

R. A. Tom, E. V. Crisan

1974-01-01

110

Infrared thermography as a nondestructive tool for materials characterisation and assessment  

Microsoft Academic Search

Thermographic approaches, passive and active, are widely used due to the outstanding advantages that offer in a number of applications and particularly for the assessment of materials. Nonetheless, there are limitations; depending upon the approach used, as well as on the materials thermal, optical and physical properties, proper assessment (detection and\\/or quantification) is feasible. In thermal non-destructive evaluation (NDE), the

N. P. Avdelidis; T.-H. Gan; C. Ibarra-Castanedo; X. P. V. Maldague

2011-01-01

111

Nondestructive testing: x-ray radiography techniques. January 1975-February 1981 (citations from the International Information Service for the Physics and Engineering Communities Data Base). Report for Jan 75-Feb 81  

SciTech Connect

This retrospective bibliography contains citations concerning X-ray radiographic techniques, equipment, and instruments for the nondestructive examination and testing of materials, objects, and structures. Nondestructive assay methods and equipment are covered also. Considerable attention is given to nondestructive stress measurement and analysis as well as to the detection of flaws or structural defects. (Contains 142 citations fully indexed and including a title list.)

Not Available

1981-03-01

112

Aggressively Passive  

E-print Network

AGRESSIVELY PASSIVE DESIGNING WITH CFD ESL-KT-13-12-48 CATEE 2013: Clean Air Through Energy Efficiency Conference, San Antonio, Texas Dec. 16-18 ESL-KT-13-12-48 CATEE 2013: Clean Air Through Energy Efficiency Conference, San Antonio, Texas Dec. 16...-18 Can passive ventilation work in a hot humid climate ESL-KT-13-12-48 CATEE 2013: Clean Air Through Energy Efficiency Conference, San Antonio, Texas Dec. 16-18 ESL-KT-13-12-48 CATEE 2013: Clean Air Through Energy Efficiency Conference, San Antonio...

Upadhyaya, K.

2013-01-01

113

Nondestructive Acoustic Imaging Techniques  

NASA Astrophysics Data System (ADS)

Acoustic imaging techniques are used in the field of nondestructive testing of technical components to measure defects such as lack of side wall fusion or cracks in welded joints. Data acquisition is performed by a remote-controlled manipulator and a PC for the mass storage of the high-frequency time-of-flight data at each probe position. The quality of the acoustic images and the interpretation relies on the proper understanding of the transmitted wave fronts and the arrangement of the probes in pulse-echo mode or in pitch-and-catch arrangement. The use of the Synthetic Aperture Focusing Technique allows the depth-dependent resolution to be replaced by a depth-independent resolution and the signal-to-noise ratio to be improved. Examples with surface-connected cracks are shown to demonstrate the improved features. The localization accuracy could be improved by entering 2-dimensional or 3-dimensional reconstructed data into the environment of a 3-dimensional CAD drawing. The propagation of ultrasonic waves through austenitic welds is disturbed by the anisotropic and inhomogeneous structure of the material. The effect is more or less severe depending upon the longitudinal or shear wave modes. To optimize the performance of an inspection software tool, a 3-dimensional CAD-Ray program has been implemented, where the shape of the inhomogeneous part of a weld can be simulated together with the grain structure based on the elastic constants. Ray-tracing results are depicted for embedded and for surface-connected defects.

Schmitz, Volker

114

Direct fissile assay of enriched uranium using random self-interrogation and neutron coincidence response  

DOEpatents

Apparatus and method for the direct, nondestructive evaluation of the .sup.235 U nuclide content of samples containing UF.sub.6, UF.sub.4, or UO.sub.2 utilizing the passive neutron self-interrogation of the sample resulting from the intrinsic production of neutrons therein. The ratio of the emitted neutron coincidence count rate to the total emitted neutron count rate is determined and yields a measure of the bulk fissile mass. The accuracy of the method is 6.8% (1.sigma.) for cylinders containing UF.sub.6 with enrichments ranging from 6% to 98% with measurement times varying from 3-6 min. The samples contained from below 1 kg to greater than 16 kg. Since the subject invention relies on fast neutron self-interrogation, complete sampling of the UF.sub.6 takes place, reducing difficulties arising from inhomogeneity of the sample which adversely affects other assay procedures.

Menlove, Howard O. (Los Alamos, NM); Stewart, James E. (Los Alamos, NM)

1986-01-01

115

Nondestructive assay holdup measurements with the Ortec detective  

SciTech Connect

Wing 4 of the Chemistry and Metallurgy Research facility at Los Alamos National Laboratory is to be downgraded from a Hazard Category 2 Nuclear Facility to a Hazard Category 3 Radiological Facility. Survey and holdup measurements are used to ensure that the total contamination levels present in the facility do not contribute enough activity to go above the Hazard Category 3 threshold quantities. Additionally, the measurement information provides an understanding of the cleanup and the equipment removal needs for the next step of decontaminating and decommissioning of the site. The Chemistry and Metallurgy Research (CMR) facility has been housing the research and experimental activities for analytical chemistry, plutonium and uranium chemistry, and metallurgy since the start of the Los Alamos National Laboratory. It is currently being replaced by the new Chemistry and Metallurgy Research Replacement facilities. As a result, the CMR is gradually closing and/or downgrading to a nonnuclear facility. In 2008, the Safeguards Science and Technology group, N-1, was assigned the task of doing survey and holdup measurements of Wing 4 of the CMR. The goal of the measurements is to provide defensible measurement data for Wing 4 of the CMR Building to be downgraded from a Hazard Category 2 Nuclear Facility to below a Hazard Category 3 Radiological Facility. In addition, the measurement information would provide an understanding of the cleanup and the equipment removal needs for the next step of decontaminating and decommissioning the site. The large areal olume of the site and the high intensity of the high-energy gamma rays of thorium, either from the background or the contaminated objects in the measured room or the adjacent rooms, present some challenges in the holdup measurements. Typical holdup techniques of point source, line, or area measurement do not work well. In order to speed up the measurement time and to accuralely account for all the isotopes present in the facility, we used a new technique that we tentatively named 'Room Holdup Measurement' to do holdup measurements of the site. This technique uses the portable, electric-cooled high-purity germanium detectors from Ortec (the Detectives) to measure the activities of the isotopes.

Vo, Duc [Los Alamos National Laboratory; Wenz, Tracy [Los Alamos National Laboratory; Bracken, David [Los Alamos National Laboratory

2009-01-01

116

Determination of Plutonium Content in Spent Fuel with Nondestructive Assay  

E-print Network

die-away self-interrogation technique,” Nuclear Instrumentstechniques being researched are the following: Delayed Gamma, Delayed Neutrons, Differential Die-Away, Differential Die-Away Self-Interrogation,techniques being researched are the following: Delayed Neutrons, 5 Differential Die- Away, 6 Differential Die-Away Self-Interrogation,

Tobin, S. J.

2010-01-01

117

Passivity control of a passive haptic device  

Microsoft Academic Search

In this paper, we propose an energy-based stability control of a passive haptic device equipped with passive actuators such as an electric brake. Unstable behavior is observed even in the passive haptic system due to time delay mainly arising from the slow update rate of the virtual environment. The force approximation, one of the major limitations of the passive haptic

Beom-Seop Kim; Mignon Park; Chang-Soon Hwang; Munsang Kim; Changhyun Cho

2004-01-01

118

Passive and Active Neutron Matrix Correction for Heterogeneous Distributions Utilizing the Neutron Imaging Technique  

SciTech Connect

Classical Non-Destructive Assay (NDA) Passive Neutron Coincidence Counting (PNCC) and Differential Die-Away (DDA) active neutron interrogation techniques [1, 2] are well suited for determining the gross matrix correction factors for homogenous mass distributions of Special Nuclear Material (SNM) within an interfering waste drum matrix. These measured passive and active matrix correction factors are crucial in quantifying the SNM mass, associated Total Measurement Uncertainty (TMU), and Minimum Detectable Activity (MDA) within the drum. When heterogeneous SNM mass distributions are encountered, the measured SNM mass, TMU and MDA biases introduced may be 100%, or greater, especially for dense hydrogenous matrices. The standard matrix correction factors can be adjusted if a coarse spatial image of the SNM mass, relative to the matrix, is available. The image can then be analyzed to determine the spatially-adjusted, matrix correction factors case by case. This image analysis approach was accomplished by modifying the standard Passive-Active Neutron (PAN) counter design [3] to accommodate a unique data acquisition architecture that supports a newly developed image acquisition and analysis application called the Neutron Imaging Technique (NIT). The NIT functionality supports both PNCC and DDA acquisition and analysis modes and exploits the symmetry between a stored set of factory acquired NIT images with those from the unknown PAN assay. The NIT result is then an adjustment to the classical correction factor reducing, if not removing, the SNM mass bias and revealing the true TMU and MDA values. In this paper we describe the NIT for the PAN design from the software and algorithmic perspectives and how this technique accommodates waste matrix drums that are difficult, from the classical standpoint, if not impossible, to extract meaningful SNM mass, TMU and MDA results. (authors)

Villani, M.F.; Croft, St. [Canberra Industries, Inc., Meriden, CT (United States); Alvarez, E.; Wilkins, C.G.; Stamp, D.; Fisher, J. [Canberra Harwell, Ltd., Didcot (United Kingdom); Ambrifi, A.; Simone, G. [Nucleco SpA, Casaccia (Italy); Bourva, L.C. [International Atomic Energy Agency, Dept. of Safeguards, Vienna (Australia)

2008-07-01

119

Nondestructive Evaluation of Pavements Ultrasonic  

E-print Network

Nondestructive Evaluation of Pavements Ð Ultrasonic Tomography Kyle Hoegh, Graduate Student Dr. Lev:// pavementndt.weebly.com #12;Outline ·! Ultrasonic Tomography Overview ·! Georgia Example ·! MnROAD ­!Joint.weebly.com #12;Ultrasonic Methods: Pros and Cons ·! Advantages ­! Multiple applications ·! Thickness

Minnesota, University of

120

Microwave holography for nondestructive testing  

NASA Technical Reports Server (NTRS)

Holographic methods permit use of very large effective apertures so that weak signals can be collected over wide area and integrated to form image. Technique, modification of side-looking radar principle, can be used at very short ranges needed for nondestructive inspection of test specimens.

Cribbs, R. W.; Lamb, B. L.

1973-01-01

121

Holographic system for nondestructive testing  

Microsoft Academic Search

A description is given of a holographic system for nondestructive testing. The system is comprised of a mirror which illuminates the test object surface; the mirror is positionable to direct illumination on an object at varying angles with respect to a line normal to the surface of the object. In this manner holograms may be produced with varying degrees of

R. L. Kurtz

1975-01-01

122

Laser ultrasound for nondestructive testing  

Microsoft Academic Search

Noncontact techniques for generating and detecting high frequency ultrasonic waves ( 1 MHz) are being explored using pulsed laser thermoelastic transduction and heterodyne interferometry respectively. In addition, holographic projection techniques are being investigated for beam shaping and beam steering of the thermoelastic waves. Possible applications of this technology include performance of ultrasonic nondestructive testing in hostile or inaccessible environments.

W. R. Scott

1982-01-01

123

Nondestructive testing by holographic interferometry  

Microsoft Academic Search

Conditions for the application of holographic interferometry as a means of nondestructive evaluation are discussed. Following a brief review of the principles of holographic interferometry, factors influencing the quality of the hologram are examined, with attention given to the parameters of the laser light source, the photographic plates, image reconstruction, the optical elements and the mechanical stability of the apparatus.

A. Piodi

1979-01-01

124

Infrared thermographic techniques for non-destructive damage characterization of carbon fibre reinforced polymers during tensile fatigue testing  

Microsoft Academic Search

A non-destructive fatigue damage characterization technique is needed in the scope of the development of new processing techniques for carbon fibre reinforced polymer (CFRP) composites. This study investigates two thermographic testing techniques with the aim of providing an in situ characterization technique of damage during fatigue testing of the mentioned CFRP specimens. A passive thermographic approach is used by measuring

R. Steinberger; T. I. Valadas Leitão; E. Ladstätter; G. Pinter; W. Billinger; R. W. Lang

2006-01-01

125

Overview of nondestructive evaluation technologies  

SciTech Connect

The infrastructure in the US and the world is aging. There is an increasing awareness of the need to assess the severity of the damage occurring to the infrastructure. Limited resources preclude the replacement of all structures that need repairs or have exceeded their life times. Methods to assess the amount and severity of damage are crucial to implementing a systematic, cost effective approach to repair and/or replace the damaged structures. The challenges of inspecting aging structures without impairing their usefulness rely on a variety of technologies and techniques for nondestructive evaluation (NDE). This paper will briefly describe several nondestructive evaluation technologies that are required for inspecting a variety of systems and structures.

Thomas, G.

1995-04-01

126

Holographic system for nondestructive testing  

NASA Technical Reports Server (NTRS)

A description is given of a holographic system for nondestructive testing. The system is comprised of a mirror which illuminates the test object surface; the mirror is positionable to direct illumination on an object at varying angles with respect to a line normal to the surface of the object. In this manner holograms may be produced with varying degrees of sensitivity enabling optimum observation of dimensions of deformation of an object occurring between test exposures.

Kurtz, R. L. (inventor)

1975-01-01

127

Nondestructive evaluation of advanced ceramics  

NASA Technical Reports Server (NTRS)

A review is presented of Lewis Research Center efforts to develop nondestructive evaluation techniques for characterizing advanced ceramic materials. Various approaches involved the use of analytical ultrasonics to characterize monolythic ceramic microstructures, acousto-ultrasonics for characterizing ceramic matrix composites, damage monitoring in impact specimens by microfocus X-ray radiography and scanning ultrasonics, and high resolution computed X-ray tomography to identify structural features in fiber reinforced ceramics.

Klima, Stanley J.; Kautz, Harold E.

1988-01-01

128

Automated UF6 Cylinder Enrichment Assay: Status of the Hybrid Enrichment Verification Array (HEVA) Project: POTAS Phase II  

SciTech Connect

Pacific Northwest National Laboratory (PNNL) intends to automate the UF6 cylinder nondestructive assay (NDA) verification currently performed by the International Atomic Energy Agency (IAEA) at enrichment plants. PNNL is proposing the installation of a portal monitor at a key measurement point to positively identify each cylinder, measure its mass and enrichment, store the data along with operator inputs in a secure database, and maintain continuity of knowledge on measured cylinders until inspector arrival. This report summarizes the status of the research and development of an enrichment assay methodology supporting the cylinder verification concept. The enrichment assay approach exploits a hybrid of two passively-detected ionizing-radiation signatures: the traditional enrichment meter signature (186-keV photon peak area) and a non-traditional signature, manifested in the high-energy (3 to 8 MeV) gamma-ray continuum, generated by neutron emission from UF6. PNNL has designed, fabricated, and field-tested several prototype assay sensor packages in an effort to demonstrate proof-of-principle for the hybrid assay approach, quantify the expected assay precision for various categories of cylinder contents, and assess the potential for unsupervised deployment of the technology in a portal-monitor form factor. We refer to recent sensor-package prototypes as the Hybrid Enrichment Verification Array (HEVA). The report provides an overview of the assay signatures and summarizes the results of several HEVA field measurement campaigns on populations of Type 30B UF6 cylinders containing low-enriched uranium (LEU), natural uranium (NU), and depleted uranium (DU). Approaches to performance optimization of the assay technique via radiation transport modeling are briefly described, as are spectroscopic and data-analysis algorithms.

Jordan, David V.; Orton, Christopher R.; Mace, Emily K.; McDonald, Benjamin S.; Kulisek, Jonathan A.; Smith, Leon E.

2012-06-01

129

Topoisomerase assays.  

PubMed

Topoisomerases are nuclear enzymes that play essential roles in DNA replication, transcription, chromosome segregation, and recombination. All cells have two major forms of topoisomerases: type I enzymes, which make single-stranded cuts in DNA, and type II enzymes, which cut and pass double-stranded DNA. DNA topoisomerases are important targets of approved and experimental anti-cancer agents. The protocols described in this unit are for assays used to assess new chemical entities for their ability to inhibit both forms of DNA topoisomerase. Included are an in vitro assay for topoisomerase I activity based on relaxation of supercoiled DNA, and an assay for topoisomerase II based on the decatenation of double-stranded DNA. The preparation of mammalian cell extracts for assaying topoisomerase activity is described, along with a protocol for an ICE assay to examine topoisomerase covalent complexes in vivo, and an assay for measuring DNA cleavage in vitro. PMID:22684721

Nitiss, John L; Soans, Eroica; Rogojina, Anna; Seth, Aman; Mishina, Margarita

2012-06-01

130

49 CFR 195.234 - Welds: Nondestructive testing.  

Code of Federal Regulations, 2010 CFR

...3 2010-10-01 2010-10-01 false Welds: Nondestructive testing. 195.234 Section...LIQUIDS BY PIPELINE Construction § 195.234 Welds: Nondestructive testing. (a) A weld may be nondestructively tested by any...

2010-10-01

131

49 CFR 195.234 - Welds: Nondestructive testing.  

Code of Federal Regulations, 2011 CFR

...3 2011-10-01 2011-10-01 false Welds: Nondestructive testing. 195.234 Section...LIQUIDS BY PIPELINE Construction § 195.234 Welds: Nondestructive testing. (a) A weld may be nondestructively tested by any...

2011-10-01

132

49 CFR 195.234 - Welds: Nondestructive testing.  

Code of Federal Regulations, 2013 CFR

...3 2013-10-01 2013-10-01 false Welds: Nondestructive testing. 195.234 Section...LIQUIDS BY PIPELINE Construction § 195.234 Welds: Nondestructive testing. (a) A weld may be nondestructively tested by any...

2013-10-01

133

49 CFR 195.234 - Welds: Nondestructive testing.  

Code of Federal Regulations, 2012 CFR

...3 2012-10-01 2012-10-01 false Welds: Nondestructive testing. 195.234 Section...LIQUIDS BY PIPELINE Construction § 195.234 Welds: Nondestructive testing. (a) A weld may be nondestructively tested by any...

2012-10-01

134

Nondestructive characterization of materials with variable properties  

Microsoft Academic Search

Summary Materials with continuous variable properties in time and space are considered. The possibility of nondestructive characterization of these materials on the basis of nonlinear longitudinal wave propagation data is discussed on the basis of recent results. The model direct and inverse problems are solved. The utilization of obtained results enables one to solve several nondestructive material characterization problems.

A. Ravasoo; J. Janno

2001-01-01

135

Nondestructive examination using neutron activated positron annihilation  

DOEpatents

A method is provided for performing nondestructive examination of a metal specimen using neutron activated positron annihilation wherein the positron emitter source is formed within the metal specimen. The method permits in situ nondestructive examination and has the advantage of being capable of performing bulk analysis to determine embrittlement, fatigue and dislocation within a metal specimen.

Akers, Douglas W. (Idaho Falls, ID); Denison, Arthur B. (Idaho Falls, ID)

2001-01-01

136

Holographic nondestructive evaluation: status and future  

Microsoft Academic Search

The results and conclusions of an extensive review of the literature and practice of holographic nondestructive evaluation (NDE) are reported. Although this technique has several technically unique features, and has been shown to be a feasible nondestructive testing technique in a very large number of laboratory investigations, its commercial application is rare. A counter example is its prevalent use in

C. M. Birnbaum; C. M. Vest

1983-01-01

137

Nondestructive testing by speckle-shearing interferometry  

Microsoft Academic Search

The paper presents a new optical method of nondestructive evaluation which utilizes a speckle-shearing interferometric technique. This new method is referred to as SNDT. SNDT is generally superior to holographic nondestructive testing (HNDT) in the sense that it measures displacement derivatives instead of displacement. Since strains are functions of displacement derivatives, it is easier to correlate imperfections with strain anomalies

Y. Y. Hung; J. D. Hovanesian

1979-01-01

138

Waste Examination Assay Facility operations: TRU waste certification  

SciTech Connect

The ORNL Waste Examination Assay Facility (WEAF) was established to nondestructively assay (NDA) transuranic (TRU) waste generated at Oak Ridge National Laboratory (ORNL). The present facility charter encompasses the NDA and nondestructive examination (NDE) of both TRU and low-level wastes (LLW). Presently, equipment includes a Neutron Assay System (NAS), a Segmented Gamma Scanner (SGS), a drum-sized Real-Time Radiography (RTR) system, and a Neutron Slab Detector (NSD). The first three instruments are computer interfaced. Approximately 2300 TRU waste drums have been assayed with the NAS and the SGS. Another 3000 TRU and LLW drums have been examined with the RTR unit. Computer data bases have been developed to collate the large amount of data generated during the assays and examinations. 6 refs., 1 tab.

Schultz, F.J.; Caylor, B.A.; Coffey, D.E.; Phoenix, L.B.

1987-01-01

139

The Nuclear Renaissance — Implications on Quantitative Nondestructive Evaluations  

NASA Astrophysics Data System (ADS)

The world demand for energy is growing rapidly, particularly in developing countries that are trying to raise the standard of living for billions of people, many of whom do not even have access to electricity. With this increased energy demand and the high and volatile price of fossil fuels, nuclear energy is experiencing resurgence. This so-called nuclear renaissance is broad based, reaching across Asia, the United States, Europe, as well as selected countries in Africa and South America. Some countries, such as Italy, that have actually turned away from nuclear energy are reconsidering the advisability of this design. This renaissance provides the opportunity to deploy more advanced reactor designs that are operating today, with improved safety, economy, and operations. In this keynote address, I will briefly present three such advanced reactor designs in whose development Westinghouse is participating. These designs include the advanced passive PWR, AP1000, which recently received design certification for the US Nuclear Regulatory Commission; the Pebble Bed Modular reactor (PBMR) which is being demonstrated in South Africa; and the International Reactor Innovative and Secure (IRIS), which was showcased in the US Department of Energy's recently announced Global Nuclear Energy Partnership (GNEP), program. The salient features of these designs that impact future requirements on quantitative nondestructive evaluations will be discussed. Such features as reactor vessel materials, operating temperature regimes, and new geometric configurations will be described, and mention will be made of the impact on quantitative nondestructive evaluation (NDE) approaches.

Matzie, Regis A.

2007-03-01

140

Neutron Generators for Spent Fuel Assay  

Microsoft Academic Search

The Next Generation Safeguards Initiative (NGSI) of the U.S. DOE has initiated a multi-lab\\/university collaboration to quantify the plutonium (Pu) mass in, and detect the diversion of pins from, spent nuclear fuel (SNF) assemblies with non-destructive assay (NDA). The 14 NDA techniques being studied include several that require an external neutron source: Delayed Neutrons (DN), Differential Die-Away (DDA), Delayed Gammas

Ludewigt; Bernhard A

2010-01-01

141

Nondestructive Imaging of Individual Biomolecules  

SciTech Connect

Radiation damage is considered to be the major problem that still prevents imaging an individual biological molecule for structural analysis. So far, all known mapping techniques using sufficient short wavelength radiation, be it x rays or high energy electrons, circumvent this problem by averaging over many molecules. Averaging, however, leaves conformational details uncovered. Even the anticipated use of ultrashort but extremely bright x-ray bursts of a free electron laser shall afford averaging over 10{sup 6} molecules to arrive at atomic resolution. Here, we present direct experimental evidence for nondestructive imaging of individual DNA molecules. In fact, we show that DNA withstands coherent low energy electron radiation with deBroglie wavelength in the Angstrom regime despite a vast dose of 10{sup 8} electrons/nm{sup 2} accumulated over more than one hour.

Germann, Matthias; Latychevskaia, Tatiana; Escher, Conrad; Fink, Hans-Werner [Institute of Physics, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich (Switzerland)

2010-03-05

142

Advances in nondestructive evaluation technology  

NASA Technical Reports Server (NTRS)

Research at NASA Langley's Materials Characterization Instrumentation Section has followed the philosophy of improving the science base of nondestructive evaluation and advancing the state of the art of quantitative interpretability of physical measurements of materials. Details of several R&D programs choosen to highlight the last several years are given. Applications of these technologies are presented in the area of stress measurement, characterization of metal heat treatment, and evaluation of material internal structure. A second focus of the program is on quantitative transducers/measurements that have resulted in better data in irregular inhomogeneous materials such as composites. Examples are presented of new capabilities resulting from these advances that include fatigue and impact damage evaluation.

Heyman, J. S.

1982-01-01

143

Nondestructive evaluation of structural ceramics  

NASA Technical Reports Server (NTRS)

A review is presented on research and development of techniques for nondestructive evaluation and characterization of advanced ceramics for heat engine applications. Highlighted in this review are Lewis Research Center efforts in microfocus radiography, scanning laser acoustic microscopy (SLAM), scanning acoustic microscopy (SAM), scanning electron acoustic microscopy (SEAM), and photoacoustic microscopy (PAM). The techniques were evaluated by applying them to research samples of green and sintered silicon nitride and silicon carbide in the form of modulus-of-rupture bars containing seeded voids. Probabilities of detection of voids were determined for diameters as small as 20 microns for microfucus radiography, SLAM, and SAM. Strengths and limitations of the techniques for ceramic applications are identified. Application of ultrasonics for characterizing ceramic microstructures is also discussed.

Klima, Stanley J.; Baaklini, George Y.; Abel, Phillip B.

1987-01-01

144

Fundamental studies on passivity and passivity breakdown  

SciTech Connect

Using photoelectrochemical impedance and admittance spectroscopies, a fundamental and quantitative understanding of the mechanisms for the growth and breakdown of passive films on metal and alloy surfaces in contact with aqueous environments is being developed. A point defect model has been extended to explain the breakdown of passive films, leading to pitting and crack growth and thus development of damage due to localized corrosion.

Macdonald, D.D.; Urquidi-Macdonald, M.

1993-06-01

145

From Reflexive to Passive  

E-print Network

Previous approaches to the passive development from a reflexive marking focus on how the former is similar to the latter semantically and syntactically. I show that the passive evolution is better understood by looking at ...

Sohn, Joong-Sun

1998-01-01

146

Passive storage technologies  

NASA Astrophysics Data System (ADS)

Advances in storage technology and how passive techniques could be applied to the storage of propellants at the space station are described. The devices considered are passive orbital disconnect struts, cooled shield optimization, liftweight shields and catalytic converters.

Kittel, P.

1984-04-01

147

Tropospheric Passive Remote Sensing  

NASA Technical Reports Server (NTRS)

The long term role of airborne/spaceborne passive remote sensing systems for tropospheric air quality research and the identification of technology advances required to improve the performance of passive remote sensing systems were discussed.

Keafer, L. S., Jr. (editor)

1982-01-01

148

Passivation of Anodic Reactions.  

National Technical Information Service (NTIS)

Extending the Wagner definition of passivity to anodic reactions of chemical species on inert electrodes, passivation of a Pt electrode for the hydrogen oxidation reaction can be explained as being caused by small amounts (fraction of a monolayer) of adso...

S. Schuldiner

1968-01-01

149

Interlanguage Passive Construction  

ERIC Educational Resources Information Center

Because the appearance of the passive construction varies cross linguistically, differences exist in the interlanguage (IL) passives attempted by learners of English. One such difference is the widely studied IL pseudo passive, as in "*new cars must keep inside" produced by Chinese speakers. The belief that this is a reflection of L1 language…

Simargool, Nirada

2008-01-01

150

Analytical expressions for the gate utilization factors of passive multiplicity counters including signal build-up  

Microsoft Academic Search

In the realm of nuclear safeguards, passive neutron multiplicity counting using shift register pulse train analysis to nondestructively quantify Pu in product materials is a familiar and widely applied technique. The approach most commonly taken is to construct a neutron detector consisting of ³He filled cylindrical proportional counters embedded in a high density polyethylene moderator. Fast neutrons from the item

Stephen Croft; Louise G Evans; Melissa A Schear

2010-01-01

151

Nondestructive Determination of Bond Strength  

NASA Technical Reports Server (NTRS)

Although many nondestructive techniques have been applied to detect disbonds in adhesive joints, no absolutely reliable nondestructive method has been developed to detect poor adhesion and evaluate the strength of bonded joints prior to the present work which used nonlinear ultrasonic methods to investigate adhesive bond cure conditions. Previously, a variety of linear and nonlinear ultrasonic methods with water coupling had been used to study aluminum-adhesive-aluminum laminates, prepared under different adhesive curing conditions, for possible bond strength determination. Therefore, in the course of this research effort, a variety of finite-amplitude experimental methods which could possibly differentiate various cure conditions were investigated, including normal and oblique incidence approaches based on nonlinear harmonic generation as well as several non-collinear two-wave interaction approaches. Test samples were mechanically scanned in various ways with respect to the focus of a transmitting transducer operated at several variable excitation frequencies and excitation levels. Even when powerful sample-related resonances were exploited by means of a frequency scanning approach, it was very difficult to isolate the nonlinear characteristics of adhesive bonds. However, a multi-frequency multi-power approach was quite successful and reliable. Ultrasonic tone burst signals at increasing power levels, over a wide frequency range, were transmitted through each bond specimen to determine its excitation dependent nonlinear harmonic resonance behavior. Relative amplitude changes were observed particularly in the higher harmonic spectral data and analyzed using a local displacement and strain analysis in the linear approximation. Two analysis approaches of the excitation-dependent data at specific resonances were found to be quite promising. One of these approaches may represent a very robust algorithm for classifying an adhesive bond as being properly cured or not. Another approach, in addition to differentiation between various cure conditions, may even provide information with respect to the bond strength. Several technical papers were published during the course of this research and a summary is presented in the Ph.D. dissertation of Tobias P. Berndt, a graduate student financially supported by this NASA Grant.

2000-01-01

152

A non-destructive transformer oil tester  

E-print Network

A new non-destructive test of transformer oil dielectric strength is a promising technique to automate and make more reliable a diagnostic that presently involves intensive manual efforts. This thesis focuses some of the ...

Cargol, Timothy L. (Timothy Lawrence), 1976-

2000-01-01

153

NONDESTRUCTIVE MULTIELEMENT INSTRUMENTAL NEUTRON ACTIVATION ANALYSIS  

EPA Science Inventory

A nondestructive instrumental neutron activation analysis procedure permitted accurate and sensitive measurement of most elements with atomic numbers between 11 and 92. The sensitivity of the procedure was dependent on each element's intrinsic characteristics and the sample matri...

154

Nondestructive Evaluation of Aircraft and Spacecraft Wiring  

NASA Technical Reports Server (NTRS)

Spacecraft, and especially aircraft, often fry well past their original design lives and, therefore, the need to develop nondestructive evaluation procedures for inspection of vital structures in these craft is extremely important. One of the more recent problems is the degradation of wiring and wiring insulation. The present paper describes several nondestructive characterization methods which afford the possibility to detect wiring and insulation degradation in-situ prior to major problems with the safety of aircraft and spacecraft.

White, John E.; Tucholski, Edward J.; Green, Robert E., Jr.

2004-01-01

155

Shearography in Experimental Mechanics and Nondestructive Testing  

NASA Astrophysics Data System (ADS)

This paper reviews shearography and its applications in experimental mechanics and nondestructive testing. Shearography is an interferometric method for measuring surface displacement derivatives. Unlike holography, it does not require special vibration isolation; hence it can be employed in field/factory environments. The technique has already received wide industrial acceptance for nondestructive testing. Other applications include strain measurement, material characterization, residual stress evaluation, vibration studies and 3D shape measurement.

Hung, Y. Y.

156

System Performance and Monte Carlo Analysis of Light Water Reactor Spent Fuel Assay Using Neutron Slowing Down Time Method  

Microsoft Academic Search

There is a compelling safeguards need to assay nondestructively fissile plutonium from fissile uranium in spent light water reactor fuel. Present methods suffer from a number of limitations and are incapable of providing accurate and independent safeguards assay information. The only feasible method capable of performing the required assay of spent fuel is the slowing down time (SDT) method. The

Naeem Mohamed Abdurrahman

1991-01-01

157

Microcomputers and nondestructive test systems  

SciTech Connect

Microcomputers are finding their way into Nondestructive Testing (NDT) Systems. They can be used for scanning system motion control, instrumentation control, data acquisition, data display, and data analysis. This paper describes the application of the Digital Equipment Corporation (DEC), LSI-11 series microcomputers in systems developed and used by the NDT Unit of the Los Alamos National Laboratory. These systems are used for ultrasonic testing and industrial computerized tomography. In some systems more than one microcomputer is used with one acting as a slave to the controlling or master unit. This becomes necessary when the single processor is not capable of handling all required tasks within the interval between data samples or other time constraints. The systems can be interfaced to a variety of NDT instrumentation. If the instrument has a digital command interface, then data and commands are passed back and forth through this interface. Frequently, the NDT instrumentation used does not have a digital capability and has only analog outputs. A general purpose interface has been designed and built to accept and digitize these inputs and to also display data on a storage cathode ray tube display. The systems contain translator circuits to drive stepper motors. While each system is normally coupled to a specific scanning device, its use is not restricted to only that scanner since the system can be easily programmed to drive other motors or scanners. Motors of almost any size or torque rating can be used without changing anything in the basic control system. A translator card and adequate power supply are the only changes that might be required, and a software change might also be required to keep the motor speed within its operating limits. Therefore, special purpose fixtures can be designed, built, and interfaced to the control system to perform inspections of special parts when the part has an axis of symmetry that can be used to simplify the scanning process.

Strong, R.D.

1983-01-01

158

Passive walking with knees  

Microsoft Academic Search

It is shown that passive dynamic walking, a phenomenon originally described for bipeds having straight legs, also works with knees. Thus, giving only a downhill slope as a source of energy, a human-like pair of legs will settle into a natural gait generated by the passive interaction of gravity and inertia. No muscular input is required. The physics is much

T. McGeer

1990-01-01

159

Passive magnetic bearing configurations  

DOEpatents

A journal bearing provides vertical and radial stability to a rotor of a passive magnetic bearing system when the rotor is not rotating and when it is rotating. In the passive magnetic bearing system, the rotor has a vertical axis of rotation. Without the journal bearing, the rotor is vertically and radially unstable when stationary, and is vertically stable and radially unstable when rotating.

Post, Richard F. (Walnut Creek, CA)

2011-01-25

160

Holographic nondestructive evaluation: status and future  

SciTech Connect

The results and conclusions of an extensive review of the literature and practice of holographic nondestructive evaluation (NDE) are reported. Although this technique has several technically unique features, and has been shown to be a feasible nondestructive testing technique in a very large number of laboratory investigations, its commercial application is rare. A counter example is its prevalent use in testing of aircraft and heavy equipment tires. The status of the technique is reviewed, recent and potential technical advances are enumerated, and suggestions of activities which would enable full realization and evaluation of the potential of holographic NDE in the future are made.

Birnbaum, C.M.; Vest, C.M.

1983-01-01

161

Passive solar construction handbook  

SciTech Connect

Many of the basic elements of passive solar design are reviewed. The unique design constraints presented in passive homes are introduced and many of the salient issues influencing design decisions are described briefly. Passive solar construction is described for each passive system type: direct gain, thermal storage wall, attached sunspace, thermal storage roof, and convective loop. For each system type, important design and construction issues are discussed and case studies illustrating designed and built examples of the system type are presented. Construction details are given and construction and thermal performance information is given for the materials used in collector components, storage components, and control components. Included are glazing materials, framing systems, caulking and sealants, concrete masonry, concrete, brick, shading, reflectors, and insulators. The Load Collector Ratio method for estimating passive system performance is appended, and other analysis methods are briefly summarized. (LEW)

Levy, E.; Evans, D.; Gardstein, C.

1981-08-01

162

Nondestructive Inspection and Life Determination of Disc Material.  

National Technical Information Service (NTIS)

The prime role of nondestructive evaluation is to support development and validation of the two main processes: the materials and manufacturing method design and engineering design of the engine. The second role of nondestructive evaluation is to monitor,...

H. K. Craig

1991-01-01

163

Passive Optical PassiveOpticalNetworks Contents  

E-print Network

Optical Networks (PON) · TDM-PON ­ Physical Layer and Devices ­ Traffic Distribution/Scheduling ­ Power Budget ­ Standards · APON/BPON · EPON · GPON · WDM-PONs ­ Proposed solutions #12;Passive. There is the need for specific access network technologies Access Network Hub Remote node Remote node ... NIU NIU

Mellia, Marco

164

SWEPP PAN assay system uncertainty analysis: Active mode measurements of solidified aqueous sludge waste  

SciTech Connect

The Idaho National Engineering and Environmental Laboratory is being used as a temporary storage facility for transuranic waste generated by the US Nuclear Weapons program at the Rocky Flats Plant (RFP) in Golden, Colorado. Currently, there is a large effort in progress to prepare to ship this waste to the Waste Isolation Pilot Plant (WIPP) in Carlsbad, New Mexico. In order to meet the TRU Waste Characterization Quality Assurance Program Plan nondestructive assay compliance requirements and quality assurance objectives, it is necessary to determine the total uncertainty of the radioassay results produced by the Stored Waste Examination Pilot Plant (SWEPP) Passive Active Neutron (PAN) radioassay system. This paper is one of a series of reports quantifying the results of the uncertainty analysis of the PAN system measurements for specific waste types and measurement modes. In particular this report covers active mode measurements of weapons grade plutonium-contaminated aqueous sludge waste contained in 208 liter drums (item description codes 1, 2, 7, 800, 803, and 807). Results of the uncertainty analysis for PAN active mode measurements of aqueous sludge indicate that a bias correction multiplier of 1.55 should be applied to the PAN aqueous sludge measurements. With the bias correction, the uncertainty bounds on the expected bias are 0 {+-} 27%. These bounds meet the Quality Assurance Program Plan requirements for radioassay systems.

Blackwood, L.G.; Harker, Y.D.; Meachum, T.R.

1997-12-01

165

Method for non-destructive testing  

DOEpatents

Non-destructive testing method may include providing a source material that emits positrons in response to bombardment of the source material with photons. The source material is exposed to photons. The source material is positioned adjacent the specimen, the specimen being exposed to at least some of the positrons emitted by the source material. Annihilation gamma rays emitted by the specimen are detected.

Akers, Douglas W. (Idaho Falls, ID)

2011-08-30

166

49 CFR 193.2321 - Nondestructive tests.  

Code of Federal Regulations, 2013 CFR

...Nondestructive tests. (a) The butt welds in metal shells of storage tanks with...193.2013), except that 100 percent of welds that are both longitudinal (or meridional...psig or less, ultrasonic examinations of welds on metal containers must comply with...

2013-10-01

167

49 CFR 193.2321 - Nondestructive tests.  

Code of Federal Regulations, 2012 CFR

...Nondestructive tests. (a) The butt welds in metal shells of storage tanks with...193.2013), except that 100 percent of welds that are both longitudinal (or meridional...psig or less, ultrasonic examinations of welds on metal containers must comply with...

2012-10-01

168

49 CFR 193.2321 - Nondestructive tests.  

Code of Federal Regulations, 2010 CFR

...Nondestructive tests. (a) The butt welds in metal shells of storage tanks with...193.2013), except that 100 percent of welds that are both longitudinal (or meridional...psig or less, ultrasonic examinations of welds on metal containers must comply with...

2010-10-01

169

49 CFR 193.2321 - Nondestructive tests.  

Code of Federal Regulations, 2011 CFR

...Nondestructive tests. (a) The butt welds in metal shells of storage tanks with...193.2013), except that 100 percent of welds that are both longitudinal (or meridional...psig or less, ultrasonic examinations of welds on metal containers must comply with...

2011-10-01

170

Nondestructive Inspection Of Foam And Multilayer Insulations  

NASA Technical Reports Server (NTRS)

Techniques and equipment enable nondestructive inspection of sprayed-on foam and multilayer reflecting thermal insulations on metallic substrates. Technology is applied in factories and laboratories; to inspect insulation on cryogenic tanks and pipes. Equipment includes probe head, several electronic modules that take measurements via electromagnetic and electrostatic sensors in probe head, small computer to store and process signals from modules, and printer.

Krause, Dennis R.; Bauman, Robert J.; Davis, Thomas J.

1989-01-01

171

6 Nondestructive Estimation of Foliar Pigment  

E-print Network

by accurate measurements of the pigments present in plant leaves that play very important role in plant photosynthesis and protection. There are three major classes of pigments found in plants: chlorophylls141 6 Nondestructive Estimation of Foliar Pigment (Chlorophylls, Carotenoids, and Anthocyanins

Gitelson, Anatoly

172

Nondestructive visual inspection of aging aircraft  

Microsoft Academic Search

The in-flight structural failure of an Aloha Airlines 737-200 in April of 1988 brought international attention to the aging aircraft issue and prompted operators to improve inspection and maintenance procedures for their fleets. The use of nondestructive visual inspection equipment such as borescopes, fiberscopes, and videoimagescopes allow maintenance personnel to inspect internal aircraft structure for corrosion and fatigue without costly

Peter Samsonov

1995-01-01

173

Corrosion quantification by different nondestructive inspection methods  

Microsoft Academic Search

Boeing investigated corrosion effects on crack growth rates under a USAF contract with Tinker AFB in an engineering assignment performed by the Boeing Wichita. Sixty-eight crack growth specimens were notched, corroded, and fatigue test to determine crack growth rates. After salt spray exposure and crack growth testing the specimens were nondestructively inspected (NDI) by five different NDI methods to determine

Paul S. Rutherford; Joe J. Luzar

1999-01-01

174

EDDY CURRENT MODELLING FOR NONDESTRUCTIVE TESTING  

Microsoft Academic Search

Abstract: Eddy ,current nondestructive ,evaluation is widely ,used ,to inspect ,conducting ,materials during manufacture or in service. In this context, modeling is a powerful tool for inspection improvements : it helps probe- coil designers to optimise sensors for each examination requirement, it gives better understanding of the involved physics, it helps operator training and it also increases defect analysis reliability.

G. Pichenot; F. Buvat; V. Maillot; H. Voillaume

175

Holographic nondestructive testing in bone biomechanics  

Microsoft Academic Search

Holographic nondestructive testing (HNDT) is used to investigate the complex structures of bones of various shapes and sizes subjected to forces. During the course of the present study three antlered deer skulls of different species were investigated, and significant species- specific differences were observed. The HNDT method was also used to verify the advanced healing of an osteosynthetized sheep jawbone.

Raimo Silvennoinen; Kaarlo Nygren; Markku Karna

1992-01-01

176

Holographic techniques for nondestructive testing of tires  

Microsoft Academic Search

Holographic interferometric techniques were used to evaluate the feasibility of the technique in the nondestructive testing (NDT) of commercial automobile tires. Passenger tires with built-in defects were holographically inspected to determine the types of tire defects that can be detected using this method. Separations and voids were located reliably. Defects other than separations and voids were detected in some cases.

H. L. Ceccon

1972-01-01

177

Holography: The nondestructive testing of composite structures  

Microsoft Academic Search

The principle of nondestructive testing by laser holographic interferometry, and the parts to be controled (parts of motor cases in composite materials) are discussed. The test facility, which involves a complex mechanical system, is described and the technical choices are justified. The economic aspects of the technique are outlined.

P. Barbier; C. Lefloch

1985-01-01

178

Holographic nondestructive testing in bone biomechanics  

Microsoft Academic Search

Holographic interferometry is widely used in nondestructive testing of objects. During the work of the bone biomechanics the antler stress in nasal bone region of five Finnish male moose skulls showing four different nasal bone types were tested with the forces representing dynamic and static stresses.

Raimo Silvennoinen; Kaarlo Nygren; Juha Paatsama; Markku Kaernae

1991-01-01

179

Holographic nondestructive testing at the Fourier plane  

Microsoft Academic Search

A technique for the holographic nondestructive testing at the Fourier plane is proposed. An object's lateral and longitudinal rigid body translations are equivalent to linear and quadratic phase shifts in the object's Fourier spectrum. Thus a double-exposure hologram at the Fourier plane produces fringes on reconstruction which are straight for lateral and circular for longitudinal object translation. The fringes are

C. Roychoudhuri; R. Machorro

1978-01-01

180

Hood River Passive House  

SciTech Connect

The Hood River Passive Project was developed by Root Design Build of Hood River Oregon using the Passive House Planning Package (PHPP) to meet all of the requirements for certification under the European Passive House standards. The Passive House design approach has been gaining momentum among residential designers for custom homes and BEopt modeling indicates that these designs may actually exceed the goal of the U.S. Department of Energy's (DOE) Building America program to reduce home energy use by 30%-50% (compared to 2009 energy codes for new homes). This report documents the short term test results of the Shift House and compares the results of PHPP and BEopt modeling of the project.

Hales, D.

2013-03-01

181

Acquisition of the Passive  

E-print Network

This single-subject pilot study, modeled after de Villiers' 1973, investigates the subject's acquisition of the passive construction (i.e., 'The boy was hit by the girl', as opposed to The girl hit the boy'). The purposes ...

Hill, Francine

1998-01-01

182

Immunizations: Active vs. Passive  

MedlinePLUS

... physicians call passive immunizations. If you hear your pediatrician use these terms, this is what they mean. When your child receives an active immunization, the vaccine prevents an infectious disease by activating the body’s ...

183

Passive solar water heaters  

SciTech Connect

Complete descriptions and analyses of batch integral passive, solar water heaters from the first ones in this country in the 1800s to today's latest designs are provided. Separate abstracts were prepared for nine chapters in this book.

Howell, J. (ed.)

1983-01-01

184

Passive microfluidic interconnects  

E-print Network

Equipment and procedures were developed to test two passive microfluidic interconnect rings held together by the friction forces on the contact surfaces. The second design forms fluid seals by means of thin flared rings ...

Jonnalagadda, Aparna S

2005-01-01

185

SWEPP Assay System Version 2.0 software test plan and report  

SciTech Connect

The Idaho National Engineering Laboratory (INEL) Stored Waste Examination Pilot Plant (SWEPP) operations staff use nondestructive analysis methods to characterize the radiological contents of contact- handled waste containers. Containers of waste from Rocky Flats Environmental Technology Site and other DOE sites are currently stored at SWEPP. Before these containers can be shipped to the Waste Isolation Pilot Plant (WIPP), SWEPP must verify compliance with storage, shipping, and disposal requirements. One part of the SWEPP program measures neutron emissions from the containers and estimates the mass of plutonium and other transuranic (TRU) isotopes present. A Passive/Active Neutron (PAN) assay system developed at the Los Alamos National Laboratory is used to perform these measurements. A computer program named NEUT2 was used to perform the data acquisition and reduction functions for the neutron measurements. NEUT2 uses the analysis methodology outlined, but no formal documentation exists on the software itself The SWEPP Assay System (SAS) computer program replaced the NEUT2 software. The SAS software was developed using an `object model` approach. The new software incorporates the basic analysis algorithms found in NEUT2. Additional improvements include an improved user interface, the ability to change analysis parameters without having to modify the code, and other features for maintainability. The primary purpose of this test plan and report is to document the test process and to verify that the requirements for the SAS are implemented correctly. This test plan and report satisfies the testing requirements of ASME NQA-1-1994 Supplement 11S-2 for a Quality Level 2 application. The intended audiences for this test plan are the developers and verification and validation analysts for the SAS.

Ferguson, J.J.; Overlin, T.K.

1996-07-01

186

CALORIMETER-BASED ADJUSTMENT OF MULTIPLICITY DETERMINED 240PU EFF KNOWN-A ANALYSIS FOR THE ASSAY OF PLUTONIUM  

Microsoft Academic Search

In nuclear material processing facilities, it is often necessary to balance the competing demands of accuracy and throughput. While passive neutron multiplicity counting is the preferred method for relatively fast assays of plutonium, the presence of low-Z impurities (fluorine, beryllium, etc.) rapidly erodes the assay precision of passive neutron counting techniques, frequently resulting in unacceptably large total measurement uncertainties. Conversely,

Dubose

2012-01-01

187

Nondestructive imaging of an ultracold lattice gas  

NASA Astrophysics Data System (ADS)

We demonstrate the nondestructive imaging of a lattice gas of ultracold bosons. Atomic fluorescence is induced in the simultaneous presence of degenerate Raman sideband cooling. The combined influence of these processes controllably cycles an atom between a dark state and a fluorescing state while eliminating heating and loss. Through spatially resolved sideband spectroscopy following the imaging sequence, we demonstrate the efficacy of this imaging technique in various regimes of lattice depth and fluorescence acquisition rate. Our work provides an important extension of quantum gas imaging to the nondestructive detection, control, and manipulation of atoms in optical lattices. In addition, our technique can also be extended to atomic species that are less amenable to molasses-based lattice imaging.

Patil, Y. S.; Chakram, S.; Aycock, L. M.; Vengalattore, M.

2014-09-01

188

Nondestructive DNA extraction from museum specimens.  

PubMed

Natural history museums around the world hold millions of animal and plant specimens that are potentially amenable to genetic analyses. With more and more populations and species becoming extinct, the importance of these specimens for phylogenetic and phylogeographic analyses is rapidly increasing. However, as most DNA extraction methods damage the specimens, nondestructive extraction methods are useful to balance the demands of molecular biologists, morphologists, and museum curators. Here, I describe a method for nondestructive DNA extraction from bony specimens (i.e., bones and teeth). In this method, the specimens are soaked in extraction buffer, and DNA is then purified from the soaking solution using adsorption to silica. The method reliably yields mitochondrial and often also nuclear DNA. The method has been adapted to DNA extraction from other types of specimens such as arthropods. PMID:22237527

Hofreiter, Michael

2012-01-01

189

Demonstration of Antibody in Rabbit Feces after Active or Passive Parenteral Immunization  

Microsoft Academic Search

Alimentary secretions and fecal extracts were assayed for specific antibody in rabbits actively or passively immunized parenterally against a soluble protein antigen, bovine serum albumin (BSA). In contrast to earlier studies with anti-ovalbumin, circulating anti-BSA was demonstrated to pass readily into the gastrointestinal contents of either the actively or passively immunized animals. These data indicate that at least some of

J. L. McCleery; S. C. Kraft; R. M. Rothberg

1970-01-01

190

A computer-aided nondestructive inspection system  

Microsoft Academic Search

Attention is given to a computer-aided nondestructive inspection system designed for improving the speed and quality of the ultrasonic evaluation of diffusion-bonded parts of the B-1B aircraft. The system consists of a host computer, a data acquisition and multi-axis control (DAMAC) system, and a custom mechanical scanning system. The host computer uses menu-driven software to provide a user-friendly interface for

R. C. Addison Jr.; J. M. F. Lee; A. H. Muir Jr.; A. W. Thiele

1986-01-01

191

Use of robotics in nondestructive inspection  

Microsoft Academic Search

Until very recently, nondestructive inspection of aircraft components at McClellan Air Force Base had been done in the traditional way. Ultrasonic inspections have been performed using hand-held equipment. X-ray inspections were performed using film radiography with the x-ray tubes being held on cradles, tripods, or suspended from pendant-operated or manual overhead crane-type fixtures. Implementation of advanced ultrasonic and real-time x-ray

R. J. Sartell; W. J. Richards

1987-01-01

192

Development of instrumentation for magnetic nondestructive evaluation  

SciTech Connect

The use of failure-prone components in critical applications has been traditionally governed by removing such components from service prior to the expiration of their predicted life expectancy. Such early retirement of materials does not guarantee that a particular sample will not fail in actual usage. The increasing cost of such life expectancy based operation and increased demand for improved reliability in industrial settings has necessitated an alternate form of quality control. Modern applications employ nondestructive evaluation (NDE), also known as nondestructive testing (NDT), as a means of monitoring the levels and growth of defects in a material throughout its operational life. This thesis describes the modifications made to existing instrumentation used for magnetic measurements at the Center for Nondestructive Evaluation at Iowa State University. Development of a new portable instrument is also given. An overview of the structure and operation of this instrumentation is presented. This thesis discusses the application of the magnetic hysteresis and Barkhausen measurement techniques, described in Sections 1.3.1 and 1.3.2 respectively, to a number of ferromagnetic specimens. Specifically, measurements were made on a number of railroad steel specimens for fatigue characterization, and on specimens of Damascus steel and Terfenol-D for materials evaluation. 60 refs., 51 figs., 5 tabs.

Hariharan, S.

1991-09-23

193

Clinical Assay Development Program (CADP)  

Cancer.gov

Skip to Content Search this site Clinical Assay Development Program (CADP) Do you need: Advice on further development of a cancer diagnostics assay? Assay optimization? Design or implementation of assay controls, assay standards or assay calibrators? Determination

194

46 CFR 151.03-38 - Nondestructive testing.  

...Nondestructive testing includes ultrasonic examination, liquid penetrant examination, magnetic particle examination, radiographic examination, eddy current, and acoustic emission. [CGD 85-061, 54 FR 50965, Dec. 11,...

2014-10-01

195

Through Passive Measurements  

Microsoft Academic Search

We propose a passive measurement method- ology to infer and keep track of the values of two important variables associated with a TCP connection: the sender's congestion window (cwnd) and the connection round trip time (RTT). Together, these variables provide a valuable diagnostic of end-user-perceived network performance. Our methodology is validated via both simulation and concurrent active measurements, and is

Sharad Jaiswal; Gianluca Iannaccone; Christophe Diot; Jim Kurose; Don Towsley

196

Quantitative nondestructive evaluation of materials and structures  

NASA Technical Reports Server (NTRS)

An experimental investigation was undertaken to quantify damage tolerance and resistance in composite materials impacted using the drop-weight method. Tests were conducted on laminates of several different carbon-fiber composite systems, such as epoxies, modified epoxies, and amorphous and semicrystalline thermoplastics. Impacted composite specimens were examined using destructive and non-destructive techniques to establish the characteristic damage states. Specifically, optical microscopy, ultrasonic, and scanning electron microscopy techniques were used to identify impact induced damage mechanisms. Damage propagation during post impact compression was also studied.

Smith, Barry T.

1991-01-01

197

Nondestructive Technique To Assess Embrittlement In Steels  

NASA Technical Reports Server (NTRS)

Recent research at NASA Langley Research Center led to identification of nondestructive technique for detection of temper embrittlement in HY80 steel. Measures magnetoacoustic emission associated with reversible motion of domain walls at low magnetic fields. Of interest to engineers responsible for reliability and safety of various dynamically loaded and/or thermally cycled steel parts. Applications include testing of landing gears, naval vessels, and parts subjected to heat, such as those found in steam-pipe fittings, boilers, turbine rotors, and nuclear pressure vessels.

Allison, Sidney G.; Yost, William T.; Cantrell, John H.

1990-01-01

198

Neural network approach to holographic nondestructive testing.  

PubMed

A neural network approach for the automatic detection of defects by evaluation of holographic interference patterns of the loaded technical components is described. Translation- as well as rotation-invariant features are defined based on the maximal local slope of the intensity and a partition of the interference pattern into nonoverlapping areas. The training sample set is generated by computer simulation of interferograms directed by a few typical experimentally measured samples. Practical results show the feasibility of the method. A strategy for application of neural networks to any holographic nondestructive testing task is outlined. PMID:21037676

Kreis, T; Jüptner, W; Biedermann, R

1995-03-10

199

Nondestructive terahertz imaging for aerospace applications  

NASA Astrophysics Data System (ADS)

The full potential of terahertz imaging systems for nondestructive aerospace imaging applications has not been realized due to the lack of data linking damage and defects to terahertz signatures coupled with the complexity of modeling the signatures. Terahertz systems (0.1 - 2.0 THz) may be ideally suited for NDI applications because of the ability of THz radiation to penetrate through substances commonly found on the surfaces of aircraft structures while maintaining the optical resolution required to detect defects. We will discuss several systems that we have used to study the signatures of a set of target samples with known defects.

Petkie, Douglas T.; Kemp, Izaak V.; Benton, Carla; Boyer, Christopher; Owens, Lindsay; Deibel, Jason A.; Stoik, Christopher D.; Bohn, Matthew J.

2009-09-01

200

Regional passive solar design charts  

Microsoft Academic Search

The need for simple, accurate hand calculations of passive solar system performance leads to developent of region-specific passive solar design charts. The passive solar design chart requires, as an input, collector area instead of solar radiation. Annual solar heating fraction is output instead of monthly solar heating fraction. Computational effect for hand calculations is reduced by a factor of 10.

M. Utzinger; R. Bercovitz

1982-01-01

201

Fuel burn-up determination by combined passive neutron and gamma - spectrometric ND - measurements. Final report for the period 1 July 1980 - 30 April 1988.  

National Technical Information Service (NTIS)

The non-destructive gamma-spectrometric method (HRGS) and the passive neutron technique (PNT) were applied to the determination of WWER 440 reactor spent fuel assemblies burn-up for safeguard purposes. Rapid codes FISPR-2 and BUNECO were compiled on HP-85...

S. Rohar, P. Liptak, L. Krajci, V. Petenyi, R. Arlt

1988-01-01

202

Nondestructive monitoring of tissue-engineered constructs.  

PubMed

Abstract Tissue engineering as a multidisciplinary field enables the development of living substitutes to replace, maintain, or restore diseased tissue and organs. Since the term was introduced in medicine in 1987, tissue engineering strategies have experienced significant progress. However, up to now, only a few substitutes were able to overcome the gap from bench to bedside and have been successfully approved for clinical use. Substantial donor variability makes it difficult to predict the quality of tissue-engineered constructs. It is essential to collect sufficient data to ensure that poor or immature constructs are not implanted into patients. The fulfillment of certain quality requirements, such as mechanical and structural properties, is crucial for a successful implantation. There is a clear need for new nondestructive and real-time online monitoring and evaluation methods for tissue-engineered constructs, which are applicable on the biomaterial, tissue, cellular, and subcellular levels. This paper reviews current established nondestructive techniques for implant monitoring including biochemical methods and noninvasive imaging. PMID:24021591

Frese, Julia; Morgenroth, Agnieszka; Mertens, Marianne E; Koch, Sabine; Rongen, Lisanne; Vogg, Andreas T J; Zlatopolskiy, Boris D; Neumaier, Bernd; Gesche, Valentine N; Lammers, Twan; Schmitz-Rode, Thomas; Mela, Petra; Jockenhoevel, Stefan; Mottaghy, Felix M; Kiessling, Fabian

2014-04-01

203

Microwave nondestructive evaluation of thick sandwich composites  

SciTech Connect

Two microwave nondestructive testing techniques were used to inspect thick, stratified sandwich composites consisting of fiberglass epoxy laminates, foam and honeycomb constituents. Several different defects were embedded in these samples during their production. Each technique relies on the measurement of the reflected microwave energy from the composite samples using an open-ended rectangular waveguide as the inspection probe. The experiments were done at different frequencies and standoff distances based on the results of measurement parameter optimization conducted for each separate defect. The results of measurement parameter optimization conducted for each separate defect. The results of these measurements (presented in image formats) provide impressive detailed information about each defect, such as the raised edges associated with the manufacturing of the delaminations, the shape of the indentations caused by the impact fatigue defects, and surface skin fiber bundle orientations. As expected, higher frequencies provided better spatial resolutions. The importance of optimization as it pertains to successful defect detection and characterization was demonstrated both experimentally and theoretically. The results of this study clearly demonstrate the potential of microwaves as non-destructive tools for inspecting thick composite sandwich structures.

Ganchev, S.I.; Runser, R.J.; Qaddoumi, N.; Ranu, E. [Colorado State Univ., Ft. Collins, CO (United States); Carriveau, G. [Nondestructive Testing Information Analysis Center, Austin, TX (United States)

1995-04-01

204

Use of robotics in nondestructive inspection  

SciTech Connect

Until very recently, nondestructive inspection of aircraft components at McClellan Air Force Base had been done in the traditional way. Ultrasonic inspections have been performed using hand-held equipment. X-ray inspections were performed using film radiography with the x-ray tubes being held on cradles, tripods, or suspended from pendant-operated or manual overhead crane-type fixtures. Implementation of advanced ultrasonic and real-time x-ray systems required that new equipment handling and parts handling methods be devised. Aircraft flight safety considerations demanded that neutron radiography be implemented as an inspection technique in order to find low levels of moisture and corrosion in the F-111 aircraft structure and aerodynamic surfaces. Traditional nondestructive inspection (NDI) methods require removal of suspect panels from the aircraft, including some panels that were not designed to be removed. The solution to these problems was to implement NDI systems that would allow inspection of intact aircraft. A new NDI facility especially designed for the latest in technology is under construction. It will house two large maneuverable x- and n-ray systems. The approx. 90-ft-span gantry robots will scan intact aircraft with real-time x-ray and near real-time n-ray systems. A unique floor/rail-mounted n-ray system will automatically inspect the F-111 aircraft engine bays.

Sartell, R.J.; Richards, W.J.

1987-01-01

205

Applications of aerospace technology in industry: A technology transfer profile, nondestructive testing  

NASA Technical Reports Server (NTRS)

The development of nondestructive testing procedures by NASA and the transfer of nondestructive testing to technology to civilian industry are discussed. The subjects presented are: (1) an overview of the nondestructive testing field, (2) NASA contributions to the field of nondestructive testing, (3) dissemination of NASA contributions, and (4) a transfer profile. Attachments are included which provide a brief description of common nondestructive testing methods and summarize the technology transfer reports involving NASA generated nondestructive testing technology.

1972-01-01

206

Passivated niobium cavities  

DOEpatents

A niobium cavity exhibiting high quality factors at high gradients is provided by treating a niobium cavity through a process comprising: 1) removing surface oxides by plasma etching or a similar process; 2) removing hydrogen or other gases absorbed in the bulk niobium by high temperature treatment of the cavity under ultra high vacuum to achieve hydrogen outgassing; and 3) assuring the long term chemical stability of the niobium cavity by applying a passivating layer of a superconducting material having a superconducting transition temperature higher than niobium thereby reducing losses from electron (cooper pair) scattering in the near surface region of the interior of the niobium cavity. According to a preferred embodiment, the passivating layer comprises niobium nitride (NbN) applied by reactive sputtering.

Myneni, Ganapati Rao (Yorktown, VA); Hjorvarsson, Bjorgvin (Lagga Arby, SE); Ciovati, Gianluigi (Newport News, VA)

2006-12-19

207

Passive solar buildings research  

SciTech Connect

This chapter covers research advances in passive solar buildings research during the time span from 1982 through 1991. These advances fall within the following categories: (1) short-term energy monitoring, (2) heat transport by natural convection within buildings, and (3) design guidelines and design tools. In short-term energy monitoring, a simulation model of the building is calibrated, based on data taken in a 3-day test. The method accurately predicts performance over an extended period. Heat transport through doorways is characterized for complex situations that arise in passive solar buildings. Simple concepts and models adequately describe the energy transport in many situations of interest. In a new approach, design guidelines are automatically generated for any specific locality. Worksheets or an accompanying computer program allow the designer to quickly and accurately evaluate performance and investigate design alternatives. 29 refs., 19 figs., 2 tabs.

Balcomb, J.D.

1992-12-31

208

Asymmetric passive dynamic walker.  

PubMed

The objective of this research is to better understand the dynamics of gait asymmetry in humans with central nervous system damage, such as stroke, by using a model of a passive dynamic walker (PDW). By changing the mass, mass location, knee location, and leg length of one leg while leaving the parameters of the other leg unchanged, we show that stable asymmetric walking patterns exist for PDW models. The asymmetric PDW model shows several stable walking patterns that have a single, double, and quadruple repeat pattern where the step lengths between the two legs differ by over 15%. This model will allow an analysis of the passive dynamics of walking separate from the cognitive control in asymmetric human walking to test different gait rehabilitation hypotheses. PMID:22275663

Honeycutt, Craig; Sushko, John; Reed, Kyle B

2011-01-01

209

Nondestructive dynamic testing of apples for firmness evaluation  

Microsoft Academic Search

Two nondestructive dynamic test methods, low-mass impact and acoustic response, were tested and compared with destructive compression and penetration tests to evaluate apple firmness. The purpose of the study was to analyze the performance of the impact test methods for nondestructive firmness evaluation, and to assess whether the acoustic tests could add sorting capacity to low-mass impact testing in apples.

I Shmulevich; N Galili; M. S Howarth

2003-01-01

210

Weapons assessment efficiencies through use of nondestructive laser gas  

E-print Network

- 1 - Weapons assessment efficiencies through use of nondestructive laser gas sampling June 8, 2012 New weapons assessment technology engineered: nondestructive laser welding process far less expensive weapons assessment is now easier and less expensive because of a new technology developed by scientists

211

Passive fetal monitoring sensor  

NASA Technical Reports Server (NTRS)

An ambulatory, passive sensor for use in a fetal monitoring system is discussed. The invention is comprised of a piezoelectric polymer film, combined with a metallic mounting plate fastened to a belt, and electrically connected to a signal processing unit by means of a shielded cable. The purpose of the sensor is to receive pressure pulses emitted by a fetus inside an expectant mother. Additionally, the monitor will filter out pressure pulses arising from other sources, such as the maternal heart.

Zuckerwar, Allan J. (inventor); Hall, Earl T. (inventor); Baker, Donald A. (inventor); Bryant, Timothy D. (inventor)

1992-01-01

212

Subject, topic and Sesotho passive.  

PubMed

Counter to findings in English, German and Hebrew, recent acquisition studies have shown that the passive is acquired early in several non-Indo-European languages. In an attempt to explain this phenomenon, this paper addresses certain typological phenomena which influence the early acquisition of passives in Sesotho, a southern Bantu language. After outlining the structure of the Sesotho passive and its syntactic and discourse functions, I examine Sesotho-speaking children's spontaneous use of passives, showing that the acquisition of passives in Sesotho is closely linked to the fact that Sesotho subjects must be discourse topics. I conclude that a detailed examination of how passive constructions interact with other components of a given linguistic system is critical for developing a coherent and universally applicable theory of how passives are acquired. PMID:2312646

Demuth, K

1990-02-01

213

Test and evaluation of a high-sensitivity assay system for bulk transuranic waste  

SciTech Connect

During the past year, we tested and evaluated the performance of an assay system that accommodates 55-gal drums of transuranic waste at Oak Ridge National Laboratory. This neutron assay system provides a routine assay of fissile transuranic isotopes to the 1-mg sensitivity level with a pulsed active neutron interrogation based on the differential dieaway technique. A highly sensitive passive neutron measurement determines the content of spontaneous fission transuranic isotopes in each drum as well as an upper-bound estimate of the total alpha activity. All components of the combined, pulsed active and passive neutron assay system performed well on a routine basis during the test-and-evaluation period. We performed more than 400 combined passive and active assay measurements of waste drums at Oak Ridge. One-fifth of the initial set of waste drums measured contain less than 100 nCi/g of total transuranic isotopes and thus qualify legally as nontransuranic waste.

Caldwell, J.T.; Close, D.A.; Kuckertz, T.H.; Kunz, W.E.; Pratt, J.C.; Haff, K.W.; Schultz, F.J.

1983-01-01

214

NONDESTRUCTIVE EVALUATION OF CERAMIC CANDLE FILTERS  

SciTech Connect

Nondestructive evaluation (NDE) techniques have been used to reduce the potential mechanical failures and to improve the reliability of a structure. Failure of a structure is usually initiated at some type of flaw in the material. NDE techniques have been developed to determine the presence of flaws larger than an acceptable size and to estimate the remaining stiffness of a damaged structure (Chen, et. al, 1995). Ceramic candle filters have been tested for use in coal-fueled gas turbine systems. They protect gas turbine components from damage due to erosion. A total of one hundred and one candle filters were nondestructively evaluated in this study. Ninety-eight ceramic candle filters and three ceramic composite filters have been nondestructively inspected using dynamic characterization technique. These ceramic filters include twelve unused Coors alumina/mullite, twenty-four unused and fifteen used Schumacher-Dia-Schumalith TF-20, twenty-five unused and nine used Refractron 326, eight unused and three used Refractron 442T, one new Schumacher-T 10-20, and one used Schumacher-Dia-Schumalith F-40. All filters were subjected to a small excitation and the dynamic response was picked up by a piezoelectric accelerometer. The evaluation of experimental results was processed using digital signal analysis technique including various forms of data transformation. The modal parameters for damage assessment for the unexposed (unused) vs. exposed (used) specimen were based on two vibration parameters: natural frequencies and mode shapes. Finite Element models were built for each specimen type to understand its dynamic response. Linear elastic modal analysis was performed using eight nodes, three-dimensional isotropic solid elements. Conclusions based on our study indicate that dynamic characterization is a feasible NDE technique in studying structural properties of ceramic candle filters. It has been shown that the degradation of the filters due to long working hours (or excessive back pulsing conditions and high temperature transient) could be reflected from the shift of vibration frequencies. These shifts are due to changes in structural properties such as stiffness, which are directly related to the Young's modulus of the candle filters. Further studies are necessary in implementing and verifying the applicability of dynamic NDE characterization methods for actual in-situ conditions, and in establishing a systematic testing procedure for field applications. Also investigations on the filter's natural frequency due to the effect of dust cake or due to the change of boundary conditions may provide insight as to how the filter will perform in the field.

Roger H.L. Chen, Ph.D.; Alejandro Kiriakidis

1999-09-01

215

Simulated Performance of the Integrated Passive Neutron Albedo Reactivity and Self-Interrogation Neutron Resonance Densitometry Detector Designed for Spent Fuel Measurement at the Fugen Reactor in Japan  

SciTech Connect

An integrated nondestructive assay instrument, which combined the Passive Neutron Albedo Reactivity (PNAR) and the Self-Interrogation Neutron Resonance Densitometry (SINRD) techniques, is the research focus for a collaborative effort between Los Alamos National Laboratory (LANL) and the Japanese Atomic Energy Agency as part of the Next Generation Safeguard Initiative. We will quantify the anticipated performance of this experimental system in two physical environments: (1) At LANL we will measure fresh Low Enriched Uranium (LEU) assemblies for which the average enrichment can be varied from 0.2% to 3.2% and for which Gd laced rods will be included. (2) At Fugen we will measure spent Mixed Oxide (MOX-B) and LEU spent fuel assemblies from the heavy water moderated Fugen reactor. The MOX-B assemblies will vary in burnup from {approx}3 GWd/tHM to {approx}20 GWd/tHM while the LEU assemblies ({approx}1.9% initial enrichment) will vary from {approx}2 GWd/tHM to {approx}7 GWd/tHM. The estimated count rates will be calculated using MCNPX. These preliminary results will help the finalization of the hardware design and also serve a guide for the experiment. The hardware of the detector is expected to be fabricated in 2012 with measurements expected to take place in 2012 and 2013. This work is supported by the Next Generation Safeguards Initiative, Office of Nuclear Safeguards and Security, National Nuclear Security Administration.

Ulrich, Timothy J. II [Los Alamos National Laboratory; Lafleur, Adrienne M. [Los Alamos National Laboratory; Menlove, Howard O. [Los Alamos National Laboratory; Swinhoe, Martyn T. [Los Alamos National Laboratory; Tobin, Stephen J. [Los Alamos National Laboratory; Seya, Michio [Los Alamos National Laboratory; Bolind, Alan M. [Los Alamos National Laboratory

2012-07-16

216

Preliminary nondestructive evaluation manual for the space shuttle. [preliminary nondestructive evaluation  

NASA Technical Reports Server (NTRS)

Nondestructive evaluation (NDE) requirements are presented for some 134 potential fracture-critical structural areas identified, for the entire space shuttle vehicle system, as those possibly needing inspection during refurbishment/turnaround and prelaunch operations. The requirements include critical area and defect descriptions, access factors, recommended NDE techniques, and descriptive artwork. Requirements discussed include: Orbiter structure, external tank, solid rocket booster, and thermal protection system (development area).

Pless, W. M.

1974-01-01

217

Schultheiss, Schiepe, & Rawolle Hormone assays 1 Running head: HORMONE ASSAYS  

E-print Network

Schultheiss, Schiepe, & Rawolle Hormone assays 1 Running head: HORMONE ASSAYS Hormone assays Oliver: Schultheiss, O. C., Schiepe, A., & Rawolle, M. (2012). Hormone assays. In H. Cooper, P. M. Camic, D. L. Long Association. #12;Schultheiss, Schiepe, & Rawolle Hormone assays 2 Hormone assays Hormones can be assayed from

Schultheiss, Oliver C.

218

Nondestructive characterization of nanoscale layered samples.  

PubMed

Multilayered samples consisting of Al, Co and Ni nanolayers were produced by MBE and characterized nondestructively by means of SRXRF, mu-XRF, WDXRF, RBS, XRR, and destructively with SIMS. The main aims were to identify the elements, to determine their purity and their sequence, and also to examine the roughness, density, homogeneity and thickness of each layer. Most of these important properties could be determined by XRF methods, e.g., on commercial devices. For the thickness, it was found that all of the results obtained via XRR, RBS, SIMS and various XRF methods (SRXRF, mu-XRF, WDXRF) agreed with each other within the limits of uncertainty, and a constant deviation from the presets used in the MBE production method was observed. Some serious preliminary discrepancies in the results from the XRF methods were examined, but all deviations could be explained by introducing various corrections into the evaluation methods and/or redetermining some fundamental parameters. PMID:18998118

Baake, Olaf; Hoffmann, Peter S; Flege, Stefan; Ortner, Hugo M; Gottschalk, Sebastian; Berky, Wolfram; Balogh, Adam G; Ensinger, Wolfgang; Beckhoff, Burkhard; Kolbe, Michael; Gerlach, Martin; Pollakowski, Beatrix; Weser, Jan; Ulm, Gerhard; Haschke, Michael; Blokhina, Elena; Peter, Markus; Porta, Dominique; Heck, Martin

2009-01-01

219

Practical applications of nondestructive materials characterization  

SciTech Connect

Nondestructive evaluation (NDE) techniques are reviewed for applications to the industrial production of materials including microstructural, physical, and chemical analyses. NDE techniques addressed include: (1) double-pulse holographic interferometry for sealed-package leak testing; (2) process controls for noncontact metals fabrication; (3) ultrasonic detections of oxygen contamination in titanium welds; and (4) scanning acoustic microscopy for the evaluation of solder bonds. The use of embedded sensors and emerging NDE concepts provides the means for controlling the manufacturing and quality of quartz crystal resonators, nickel single-crystal turbine blades, and integrated circuits. Advances in sensor technology and artificial intelligence algorithms and the use of embedded sensors combine to make NDE technology highly effective in controlling industrial materials manufacturing and the quality of the products. 15 refs.

Green, R.E. Jr. (Johns Hopkins Univ., Baltimore, MD (United States))

1992-10-01

220

Passive propellant system  

NASA Technical Reports Server (NTRS)

A passive propellant acquisition and feed system is disclosed which acquires and feeds gas-free propellant in low or zero-g environments during orbital maneuvers and retains this propellant under high axially directed acceleration such as may be experienced during launch of a space vehicle and orbit-to-orbit transfer is described. The propellant system includes a dual compartment propellant tank with independent surface tension acquisition channels in each compartment to provide gas-free flow of pressurized liquid propellant from one compartment to the other in one direction only.

Hess, D. A.; Regnier, W. W.; Jacobs, V. L. (inventors)

1979-01-01

221

Optimizing Passive Quantum Clocks  

E-print Network

We describe protocols for passive atomic clocks based on quantum interrogation of the atoms. Unlike previous techniques, our protocols are adaptive and take advantage of prior information about the clock's state. To reduce deviations from an ideal clock, each interrogation is optimized by means of a semidefinite program for atomic state preparation and measurement whose objective function depends on the prior information. Our knowledge of the clock's state is maintained according to a Bayesian model that accounts for noise and measurement results. We implement a full simulation of a running clock with power-law noise models and find significant improvements by applying our techniques.

Michael Mullan; Emanuel Knill

2014-04-15

222

Passive solar wall collectors  

NASA Astrophysics Data System (ADS)

A study of front covers to be used in passive solar wall systems for building insulation is presented. Nineteen covers were investigated, including glass, translucid plastics and metal plates. The measurements were made under natural conditions on small concrete elements of about 0.5 sq m front surface. A mathematical model was developed and adapted to each case; by fitting the different measured curves, all the physical characteristics of the different covers were obtained. The measurements for 19 covers were presented; the results of a mathematical simulation based on meteorological data near Lausanne of two periods during the 1976-1977 winter were presented for four covers

Faist, A.; Gay, J. B.

223

Optimizing passive quantum clocks  

NASA Astrophysics Data System (ADS)

We describe protocols for passive atomic clocks based on quantum interrogation of the atoms. Unlike previous techniques, our protocols are adaptive and take advantage of prior information about the clock's state. To reduce deviations from an ideal clock, each interrogation is optimized by means of a semidefinite program for atomic state preparation and measurement whose objective function depends on the prior information. Our knowledge of the clock's state is maintained according to a Bayesian model that accounts for noise and measurement results. We implement a full simulation of a running clock with power-law noise models and find significant improvements by applying our techniques.

Mullan, Michael; Knill, Emanuel

2014-10-01

224

Non-destructive assay of mechanical components using gamma-rays and thermal neutrons  

NASA Astrophysics Data System (ADS)

This work presents the results obtained in the inspection of several mechanical components through neutron and gamma-ray transmission radiography. The 4.46 × 105 n.cm-2.s-1 thermal neutron flux available at the main port of the Argonauta research reactor in Instituto de Engenharia Nuclear has been used as source for the neutron radiographic imaging. The 412 keV ?-ray emitted by 198Au, also produced in that reactor, has been used as interrogation agent for the gamma radiography. Imaging Plates - IP specifically designed to operate with thermal neutrons or with X-rays have been employed as detectors and storage devices for each of these radiations.

Souza, Erica Silvani; de Almeida, Gevaldo L.; Souza, Maria Ines S.; Avelino, Mila R.

2013-05-01

225

An integrated approach for determining plutonium mass in spent fuel assemblies with nondestructive assay  

Microsoft Academic Search

There are a variety of reasons for quantifying plutonium (Pu) in spent fuel. Below, five motivations are listed: (1) To verify the Pu content of spent fuel without depending on unverified information from the facility, as requested by the IAEA (“independent verification”). New spent fuel measurement techniques have the potential to allow the IAEA to recover continuity of knowledge and

Martyn T. Swinhoe; Stephen J. Tobin; Mike L. Fensin; Howard O. Menlove

2009-01-01

226

QA objectives for nondestructive assay at the Waste Receiving and Processing (WRAP) Facility  

SciTech Connect

This report summarizes the validation of the WRAP NDA systems against the various QAOs. A brief description of each test and any significant conclusions is included. Variables which may have affected test outcomes are examined. This report will be reviewed semi-annually and updated as necessary.

WILLS, C.E.

1999-07-12

227

QA Objectives for Nondestructive Assay at the Waste Receiving and Processing (WRAP) Facility  

SciTech Connect

This report summarizes the validation of the WRAP NDA systems against the various QAOs. A brief description of each test and any significant conclusions is included. Variables which may have affected test outcomes are examined. This report will be reviewed semi-annually and updated as necessary.

WILLS, C.E.

1999-09-15

228

Nondestructive assay (NDA) of fissile material in gloveboxes and equipment at Rocky Flats Environmental Technology Site  

SciTech Connect

At Rocky Flats Environmental Technology Site (RFETS), a glovebox and equipment holdup measurement program called Untoward Areas was performed in FY92. These measurements were completed in selected areas of one building. After completing this task, measurements in two other buildings had been completed to assist in characterizing their entire inventory. This information was used as part of evaluating safeguards and security requirements. However, a large percent of the gloveboxes and equipment in process buildings have not been measured. Before FY97, holdup measurements were being performed prior to decommissioning and deactivation activities. To accelerate the quantification of holdup a list of areas suspected to have high amounts of holdup was compiled and funding was requested and recently received. Glovebox and equipment locations were selected by use of several selection criteria. The following steps were taken in the selection process: (1) attribute scan results (FY95) were examined and high scan result locations were selected, (2) knowledgeable personnel within and outside the organization were consulted, and (3) video characterization of the Building 707 chainveyor system was examined. Only a few of the high scan result areas from the attribute scan list had not been identified by the use of process knowledge. The primary driver for holdup measurements is Department of energy (DOE) Order 5633.3B, Section II-3, Physical Inventories.

Dreher, D.J.; Lamb, F.W.

1997-10-01

229

Nondestructive assay of EBR-II blanket elements using resonance transmission analysis  

NASA Astrophysics Data System (ADS)

Resonance transmission analysis utilizing a filtered reactor beam was examined as a means of determining the 239Pu content in Experimental Breeder Reactor - II depleted uranium blanket elements. The technique uses cadmium and gadolinium filters along with a 239Pu fission chamber to isolate the 0.3 eV resonance in 239Pu. In the energy range of this resonance (0.1 eV to 0.5 eV), the total microscopic cross-section of 239Pu is significantly greater than the cross- sections of 238U and 235U. This large difference allows small changes in the 239Pu content of a sample to result in large changes in the mass signal response. Tests with small stacks of depleted uranium and 239Pu foils indicate a significant change in response based on the 239Pu content of the foil stack. In addition, the tests indicate good agreement between the measured and predicted values of 239Pu up to approximately two weight percent.

Klann, Raymond Todd

1998-10-01

230

Non-destructive assay of mechanical components using gamma-rays and thermal neutrons  

SciTech Connect

This work presents the results obtained in the inspection of several mechanical components through neutron and gamma-ray transmission radiography. The 4.46 Multiplication-Sign 10{sup 5} n.cm{sup -2}.s{sup -1} thermal neutron flux available at the main port of the Argonauta research reactor in Instituto de Engenharia Nuclear has been used as source for the neutron radiographic imaging. The 412 keV {gamma}-ray emitted by {sup 198}Au, also produced in that reactor, has been used as interrogation agent for the gamma radiography. Imaging Plates - IP specifically designed to operate with thermal neutrons or with X-rays have been employed as detectors and storage devices for each of these radiations.

Souza, Erica Silvani; Avelino, Mila R. [PPG-EM/UERJ, R. Sao Francisco Xavier, 524, Maracana - Rio de Janeiro - RJ (Brazil); Almeida, Gevaldo L. de; Souza, Maria Ines S. [IEN/CNEN, Rua Helio de Almeida, 75, Ilha do Fundao, Rio de Janeiro - RJ (Brazil)

2013-05-06

231

Active/Passive Infrared Imaging  

NASA Astrophysics Data System (ADS)

An active/passive CO2 laser radar target acquisition sensor has been developed through cooperation of the United States Army, Navy and Air Force. The Tri-Service Laser Radar (TSLR) produces pixel-registered range, velocity, active signal intensity and passive thermal emission data. Fusion of the active and passive information allows for improved characterization and discrimination between manmade objects and natural background clutter. Simple feature synergy of the pixel-registered active and passive infor-mation also provides robust cues for wire detection algorithms.

Nettleton, J. E.; Fox, C. S.; Rohde, R. S.; Buser, R. G.

1989-12-01

232

Passive-solar construction handbook  

SciTech Connect

Many of the basic elements of passive solar design are reviewed. Passive solar construction is covered according to system type, each system type discussion including a general discussion of the important design and construction issues which apply to the particular system and case studies illustrating designed and built examples of the system type. The three basic types of passive solar systems discussed are direct gain, thermal storage wall, and attached sunspace. Thermal performance and construction information is presented for typical materials used in passive solar collector components, storage components, and control components. Appended are an overview of analysis methods and a technique for estimating performance. (LEW)

Levy, E.; Evans, D.; Gardstein, C.

1981-02-01

233

Nondestructive evaluation of composite materials - A design philosophy  

NASA Technical Reports Server (NTRS)

Efficient and reliable structural design utilizing fiber reinforced composite materials may only be accomplished if the materials used may be nondestructively evaluated. There are two major reasons for this requirement: (1) composite materials are formed at the time the structure is fabricated and (2) at practical strain levels damage, changes in the condition of the material, that influence the structure's mechanical performance is present. The fundamental basis of such a nondestructive evaluation capability is presented. A discussion of means of assessing nondestructively the material condition as well as a damage mechanics theory that interprets the material condition in terms of its influence on the mechanical response, stiffness, strength and life is provided.

Duke, J. C., Jr.; Henneke, E. G., II; Stinchcomb, W. W.; Reifsnider, K. L.

1984-01-01

234

Fly ash carbon passivation  

DOEpatents

A thermal method to passivate the carbon and/or other components in fly ash significantly decreases adsorption. The passivated carbon remains in the fly ash. Heating the fly ash to about 500 and 800 degrees C. under inert gas conditions sharply decreases the amount of surfactant adsorbed by the fly ash recovered after thermal treatment despite the fact that the carbon content remains in the fly ash. Using oxygen and inert gas mixtures, the present invention shows that a thermal treatment to about 500 degrees C. also sharply decreases the surfactant adsorption of the recovered fly ash even though most of the carbon remains intact. Also, thermal treatment to about 800 degrees C. under these same oxidative conditions shows a sharp decrease in surfactant adsorption of the recovered fly ash due to the fact that the carbon has been removed. This experiment simulates the various "carbon burnout" methods and is not a claim in this method. The present invention provides a thermal method of deactivating high carbon fly ash toward adsorption of AEAs while retaining the fly ash carbon. The fly ash can be used, for example, as a partial Portland cement replacement in air-entrained concrete, in conductive and other concretes, and for other applications.

La Count, Robert B; Baltrus, John P; Kern, Douglas G

2013-05-14

235

Passive films on magnesium anodes in primary batteries  

NASA Technical Reports Server (NTRS)

The characteristics of the passive films over Mg anodes, which essentially govern the voltage delay of the latter, have been determined nondestructively from an analysis of the transient and steady-state response of the electrode potential to low amplitude galvanostatic polarization under various experimental conditions viz., with different corrosion inhibitor coatings on Mg, after various periods of ageing of anode in solutions containing corrosion inhibitors, at various low temperatures etc. Using these parameters, the kinetics of film build-up or dissolution under these conditions have been monitored. The morphology of the anode film has been verified with scanning electron microscopy. Similar transients at low temperatures point out a steep rise in the film resistivity which is essentially responsible for the severe voltage delay. Finally, possible application of this technique in secondary Li batteries to improve cycling characteristics of the Li anode has been pointed out.

Ratnakumar, B. V.

1988-01-01

236

Ultrasonic Nondestructive Characterization of Adhesive Bonds  

NASA Technical Reports Server (NTRS)

Adhesives and adhesive joints are widely used in various industrial applications to reduce weight and costs, and to increase reliability. For example, advances in aerospace technology have been made possible, in part, through the use of lightweight materials and weight-saving structural designs. Joints, in particular, have been and continue to be areas in which weight can be trimmed from an airframe through the use of novel attachment techniques. In order to save weight over traditional riveted designs, to avoid the introduction of stress concentrations associated with rivet holes, and to take full advantage of advanced composite materials, engineers and designers have been specifying an ever-increasing number of adhesively bonded joints for use on airframes. Nondestructive characterization for quality control and remaining life prediction has been a key enabling technology for the effective use of adhesive joints. Conventional linear ultrasonic techniques generally can only detect flaws (delamination, cracks, voids, etc) in the joint assembly. However, more important to structural reliability is the bond strength. Although strength, in principle, cannot be measured nondestructively, a slight change in material nonlinearity may indicate the onset of failure. Furthermore, microstructural variations due to aging or under-curing may also cause changes in the third order elastic constants, which are related to the ultrasonic nonlinear parameter of the polymer adhesive. It is therefore reasonable to anticipate a correlation between changes in the ultrasonic nonlinear acoustic parameter and the remaining bond strength. It has been observed that higher harmonics of the fundamental frequency are generated when an ultrasonic wave passes through a nonlinear material. It seems that such nonlinearity can be effectively used to characterize bond strength. Several theories have been developed to model this nonlinear effect. Based on a microscopic description of the nonlinear interface binding force, a quantitative method was presented. Recently, a comparison between the experimental and simulated results based on a similar theoretical model was presented. A through-transmission setup for water immersion mode-converted shear waves was used to analyze the ultrasonic nonlinear parameter of an adhesive bond. In addition, ultrasonic guided waves have been used to analyze adhesive or diffusion bonded joints. In this paper, the ultrasonic nonlinear parameter is used to characterize the curing state of a polymer/aluminum adhesive joint. Ultrasonic through-transmission tests were conducted on samples cured under various conditions. The magnitude of the second order harmonic was measured and the corresponding ultrasonic nonlinear parameter was evaluated. A fairly good correlation between the curing condition and the nonlinear parameter is observed. The results show that the nonlinear parameter might be used as a good indicator of the cure state for adhesive joints.

Qu, Jianmin

1999-01-01

237

Nondestructive evaluation of compacted clayey soils  

NASA Astrophysics Data System (ADS)

Compacted clayey soils are analyzed using nondestructive testing methods. Ultrasonic testing and image analysis are used as nondestructive testing techniques. Tests were conducted on three clayey soils with low to high plasticities. The soils are compacted and then allowed to dry or subjected to wetting and drying cycles subsequent to compaction. Ultrasonic tests are performed to determine small strain elastic properties of soils during drying. Image analysis techniques are used to determine large strains and cracking behavior of soils during wetting and drying cycles. Finally, numerical methods are used to simulate large and small strain soil behavior. Ultrasonic testing can be used effectively to determine compaction characteristics of soils. Through transmission can be applicable in the laboratory or on recovered field samples while surface transmission can be used in the field. Variation of P-wave velocity is similar to variation of dry density for the test soils. Increasing compactive effort cause increases in measured wave velocity. Variations of elastic parameters during drying are investigated. More variation was observed for soils compacted with low compaction effort and high water contents. Five elastic parameters of cross-anisotropy are calculated from wave velocity measurements on cubical samples with oblique cuts. Constrained, Young's, and shear moduli increase, while Poisson's ratios decrease during drying. Starting with isotropy assumption, empirical formulas are used to calculate the shear moduli and results are compared with experimental shear modulus values obtained using the theory of elasticity. A new formulation is developed to compute shear modulus variation with saturation. Behavior of compacted clayey soils during wetting and drying was also investigated. High plasticity-fine grained soils tend to shrink and crack more during drying. Cracks of these soils tend to heal and close during wetting cycles. Cracking and healing are less for medium and low plasticity soils. Cracking is observed at relatively low suction levels for all soil types. Cracking is quantified using image analysis techniques. Finite element models are successfully used to make predictions on small strainwave propagation and fracture potential of soils. Transducer size has significant effect on surface arrangement arrival times and water content profile has significant effect on fracture potential.

Inci, Gokhan

238

NON-DESTRUCTIVE TESTING METHODS FOR GEOTHERMAL PIPING.  

SciTech Connect

Non-destructive testing is a key component of optimized plant inspection and maintenance programs. Risk based inspection, condition based maintenance and reliability centered maintenance systems all require detection, location and sizing of defects or flaws by non-destructive methods. Internal damage of geothermal piping by corrosion and erosion-corrosion is an ongoing problem requiring inspection and subsequent maintenance decisions to ensure safe and reliable performance. Conventional manual ultrasonic testing to determine remaining wall thickness has major limitations, particularly when damage is of a random and localized nature. Therefore, it is necessary to explore alternative non-destructive methods that offer potential benefits in terms of accurate quantification of size, shape and location of damage, probability of detection, ability to use on-line over long ranges, and economics. A review of non-destructive methods and their applicability to geothermal piping was performed. Based on this, ongoing research will concentrate on long range guided wave and dynamic methods.

BERNDT,M.L.

2001-03-23

239

Nondestructive Evaluation of Foam Sidewalls in Super Tiger.  

National Technical Information Service (NTIS)

A nondestructive evaluation technique has been developed for determining the locations of anomalies in the foam sidewalls of overpack-type packagings used for the shipment of radioactive materials. This technique involves heating the interior walls of the...

W. L. Uncapher, M. L. Apple

1988-01-01

240

12. VIEW OF THE NONDESTRUCTIVE TESTING EQUIPMENT BEING USED TO ...  

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

12. VIEW OF THE NON-DESTRUCTIVE TESTING EQUIPMENT BEING USED TO DETECT FLAWS IN FABRICATED COMPONENTS. (6/76) - Rocky Flats Plant, General Manufacturing, Support, Records-Central Computing, Southern portion of Plant, Golden, Jefferson County, CO

241

Nondestructive Testing and Identification for Bridge Rating: Pilot Project.  

National Technical Information Service (NTIS)

A nondestructive bridge testing scheme based on a practical impact testing methodology has been described. In this method, acceleration responses at several points on a test bridge due to impact are measured and frequency response functions are computed. ...

A. E. Aktan, M. Raghavendrachar

1990-01-01

242

Absolute nuclear material assay  

DOEpatents

A method of absolute nuclear material assay of an unknown source comprising counting neutrons from the unknown source and providing an absolute nuclear material assay utilizing a model to optimally compare to the measured count distributions. In one embodiment, the step of providing an absolute nuclear material assay comprises utilizing a random sampling of analytically computed fission chain distributions to generate a continuous time-evolving sequence of event-counts by spreading the fission chain distribution in time.

Prasad, Manoj K. (Pleasanton, CA); Snyderman, Neal J. (Berkeley, CA); Rowland, Mark S. (Alamo, CA)

2012-05-15

243

Passive Dynamic Biped Catalogue, 1991  

Microsoft Academic Search

Passive dynamic bipeds walk and run by virtue of physics inherent in the interaction of their legs and the ground; they need no motor control. A diverse spectrum of passive models are now known; together they offer a lively repertoire, including locomotion at various speeds, up and down hills, in two and three dimensions, and over unevenly-spaced footholds. We review

Tad Mcgeer

1991-01-01

244

Passive Greenhouses and Ecological Reconstruction  

Microsoft Academic Search

This paper is discussing the ecological reconstruction opportunity opened by the extended use of the energetic passive greenhouses, independent of any conventional infrastructure (water, gas, electricity). A specific passive greenhouse configuration is considered: the main heating device is a heat pump extracting energy from cold underground water. A dc wind generator is supplying the small amount of energy necessary for

V. E. Balas; M. M. Balas; M. V. Putin-Racovita

2008-01-01

245

Passive retrofits for Navy housing  

SciTech Connect

A project to assess and initiate passive solar energy retrofits to US Navy family housing is described. The current data base for Navy housing (ECOP), and its enhancement for passive solar purposes options proposed for Navy housing are explained. The analysis goals and methods to evaluate the retrofits are discussed. An educational package to explain the retrofits is described.

Hibbert, R.; Miles, C.; Jones, R.; Peck, C.; Anderson, J.; Jacobson, V.; Dale, A.M.

1985-01-01

246

Temperature initiated passive cooling system  

DOEpatents

A passive cooling system for cooling an enclosure only when the enclosure temperature exceeds a maximum standby temperature comprises a passive heat transfer loop containing heat transfer fluid having a particular thermodynamic critical point temperature just above the maximum standby temperature. An upper portion of the heat transfer loop is insulated to prevent two phase operation below the maximum standby temperature.

Forsberg, Charles W. (Oak Ridge, TN)

1994-01-01

247

6, 54275456, 2006 Passive microwave  

E-print Network

ACPD 6, 5427­5456, 2006 Passive microwave 3-D polarization effects from rainy clouds A. Battaglia in polarization signatures as observed from precipitating clouds by low frequency ground-based microwave, 5427­5456, 2006 Passive microwave 3-D polarization effects from rainy clouds A. Battaglia et al. Title

Boyer, Edmond

248

A new technique for ultrasonic nondestructive evaluation of adhesive joints  

E-print Network

A NEW TECHNIQUE FOR ULTRASONIC NONDESTRUCTIVE EVALUATION OF ADHESIVE JOINTS A Thesis by SUSAN ELISABETH HANNEMAN Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree... of MASTER OF SCIENCE December 1991 Major Subject: Aerospace Engineering A NEW TECHNIQUE FOR ULTRASONIC NONDESTRUCTIVE EVALUATION OF ADHESIVE JOINTS A Thesis by SUSAN ELISABETH HANNEMAN Approved as to style and content by: Vikram K. Kinra (Chair...

Hanneman, Susan Elisabeth

2012-06-07

249

Nondestructive methods for quality evaluation of livestock products  

Microsoft Academic Search

The muscles derived from livestock are highly perishable. Rapid and nondestructive methods are essential for quality assurance\\u000a of such products. Potential nondestructive methods, which can supplement or replace many of traditional time consuming destructive\\u000a methods, include colour and computer image analysis, NIR spectroscopy, NMRI, electronic nose, ultrasound, X-ray imaging and\\u000a biosensors. These methods are briefly described and the research work

K. Narsaiah; Shyam N. Jha

250

Proceedings of the fifteenth symposium on nondestructive evaluation  

SciTech Connect

This book presents the papers given at a symposium on nondestructive testing. Topics considered at the symposium included the acoustical holographic Siamese image technique for imaging radial cracks in reactor piping, a simulated model for the reliability of ultrasonic inspection, x-ray computed tomography, through-transmission ultrasound, the role of laser technology in materials processing and nondestructive testing, and a computer controlled array of ultrasonic transducers for fast inspection of steel pipes.

Moore, D.W.; Matzkanin, G.A.

1985-01-01

251

Non-destructive diffraction enhanced imaging of seeds  

Microsoft Academic Search

Techniques that make possible the non-destructive continuous observation of plant anatomy and develop- mental processes provide novel insights into these phenomena. Non-destructive imaging of seeds was demonstrated using the synchrotron-based X-ray im- aging technique, diffraction enhanced imaging (DEI). The seed images obtained had good contrast and definition, allowing anatomical structures and physio- logical events to be observed. Structures such as

Lester W. Young; Christopher Parham; Zhong Zhong; Dean Chapman; Martin J. T. Reaney

2007-01-01

252

Passive Optical Networks (PONs)  

NSDL National Science Digital Library

Gordon and Mike's ICT Podcast offers perspectives on the information and communication technologies (ICT) industries from Gordon Snyder and Mike Qaissaunee. In this podcast, Mike and Gordon take a look at modern day fiber optics delivery systems. The conversation focuses on innovations in the fiber optics industry. Some of these include passive optical networks, fiber P2P networks, and centralized/distributed/cascading splitting choices. The podcast concludes with a question whether or not technicians are âÂÂtypically terminating fiber in the field.â In addition to this, the authors provide a question by question transcript and references to enhance the experience. Running time for the show is 24:24.

Qaissaunee, Michael; Snyder, Gordon F.

2010-11-23

253

Passive sonar calibration spheres  

NASA Astrophysics Data System (ADS)

The need for calibrated sonar targets is addressed with the development and testing of a set of thin-walled spheres filled with a high-density fluid. Using historical research information as a guide, a set of thin-walled metal spheres was developed and filled with a high-density fluid. The combination of the spherical shape and the acoustic focusing effects of the fluid enhanced the acoustic scattering strength of the shape so that it was not only stable with temperature but also significantly greater in amplitude. The simple passive nature of the spheres makes them ideal acoustic targets for long-term unattended deployments. Using a reference level measurement, each sphere was calibrated over a wide frequency range in order to provide the user with a curve of measured scattering strength versus frequency. The resulting curves showed a high degree of correlation between the individual spheres and the modeling that was used to extrapolate the theoretical values.

Deveau, David M.

2002-05-01

254

Passive Ball Capture Joint  

NASA Technical Reports Server (NTRS)

A passive ball capture joint has a sleeve with a plurality of bores distributed about a circumference thereof and formed therethrough at an acute angle relative to the sleeve's longitudinal axis. A spring-loaded retainer is slidingly fitted in each bore and is biased such that, if allowed, will extend at least partially into the sleeve to retain a ball therein. A ring, rotatably mounted about the bores, has an interior wall defining a plurality of shaped races that bear against the spring-loaded retainers. A mechanized rotational force producer is coupled to the ring. The ring can be rotated from a first position (that presses the retainers into the sleeve to lock the ball in place) to a second position (that allows the retainers to springback out of the sleeve to release the ball).

Cloyd, Richard A. (Inventor); Bryan, Thomas C. (Inventor)

2003-01-01

255

Advanced Instrumentation, Information, and Control System Technologies: Nondestructive Examination Technologies - FY11 Report  

SciTech Connect

Licensees of commercial nuclear power plants in the US are expected to submit license renewal applications for the period of operation of 60 to 80 years which has also been referred to as long term operation (LTO). The greatest challenges to LTO are associated with degradation of passive components as active components are routinely maintained and repaired or placed through maintenance programs. Some passive component degradation concerns include stress corrosion cracking (SCC) of metal components, radiation induced embrittlement of the reactor pressure vessel (RPV), degradation of buried piping, degradation of concrete containment structures, and degradation of cables. Proactive management of passive component aging employs three important elements including online monitoring of degradation, early detection of degradation at precursor stages, and application of prognostics for the prediction of remaining useful life (RUL). This document assesses several nondestructive examination (NDE) measurement technologies for integration into proactive aging management programs. The assessment is performed by discussing the three elements of proactive aging management identified above, considering the current state of the industry with respect to adopting these key elements, and analyzing measurement technologies for monitoring large cracks in metal components, monitoring early degradation at precursor stages, monitoring the degradation of concrete containment structures, and monitoring the degradation of cables. Specific and general needs have been identified through this assessment. General needs identified include the need for environmentally rugged sensors are needed that can operate reliably in an operating reactor environment, the need to identify parameters from precursor monitoring technologies that are unambiguously correlated with the level of pre-macro defect damage, and a methodology for identifying regions where precursor damage is most likely to initiate.

Meyer, Ryan M.; Coble, Jamie B.; Ramuhalli, Pradeep; Bond, Leonard J.

2011-08-30

256

A computer-aided nondestructive inspection system  

NASA Astrophysics Data System (ADS)

Attention is given to a computer-aided nondestructive inspection system designed for improving the speed and quality of the ultrasonic evaluation of diffusion-bonded parts of the B-1B aircraft. The system consists of a host computer, a data acquisition and multi-axis control (DAMAC) system, and a custom mechanical scanning system. The host computer uses menu-driven software to provide a user-friendly interface for the operator; an array processor permits the acquisition of entire waveforms for subsequent analysis. In order to eliminate time-consuming part alignment procedures, the DAMAC permits raster scans to be performed on parts that lie at arbitrary orientation with respect to the tank. In addition, the DAMAC controls the ultrasonic pulser-receiver and synchronizes the data acquisition with the scanning motions. The custom mechanical scanning system contains three servo-controlled linear axes capable of vector movements within a 10 x 16 x 3 ft volume; the scanning speed is 20 ips.

Addison, R. C., Jr.; Lee, J. M. F.; Muir, A. H., Jr.; Thiele, A. W.

257

Nondestructive methods to assess dental implant stability  

NASA Astrophysics Data System (ADS)

The robustness and reliability of two nondestructive evaluation methods to assess dental prostheses stability is presented. The study aims at addressing an increasing need in the biomedical area where robust, reliable, and noninvasive methods to assess the bone-interface of dental and orthopedic implants are increasingly demanded for clinical diagnosis and direct prognosis. The methods are based on the electromechanical impedance method and on the propagation of solitary waves. Nobel Biocare® 4.3 x 13 mm implants were entrenched inside bovine rib bones that were immersed inside Normal Saline for 24 hours before test in order to avoid dehydration and simulating physiologic osmolarity of the corticocancellous bone and plasma. Afterwards the bones were immersed in a solution of nitric acid to allow material degradation, inversely simulating a bone-healing process. This process was monitored by bonding a Piezoceramic Transducer (PZT) to the abutment and measuring the electrical admittance of the PZT over time. On the other hand the bones calcium loss was calculated after immersing in acid by Atomic Absorption Spectroscopy over time for comparison. Moreover a novel transducer based on the generation and detection of highly nonlinear solitary waves was used to assess the stiffness of the abutment-implant bone. In these experiments it was found that the PZT's conductance and some of the solitary waves parameters are sensitive to the degradation of the bones and was correlated to the bone calcium loss over time.

Rizzo, Piervincenzo; Tabrizi, Aydin; Berhanu, Bruk; Ochs, Mark W.

2012-04-01

258

Nondestructive Evaluation of Reactive Powder Concrete  

NASA Astrophysics Data System (ADS)

Reactive powder concrete (RPC) has been introduced as a structural material for civil engineering applications. The material consists of a finely graded combination of cement, sand, ground quartz and silica fume which combined with water form a cement paste. Small steel fibers measuring approximately 0.2 mm in diameter and 12 mm in length are distributed throughout the cement matrix and the combined material has very high compressive strength and toughness. The material is proposed for use in the primary load bearing members in bridges, and as such nondestructive evaluation technologies are needed to evaluate material quality and monitor in-service condition. This paper reports on research to determine the effectiveness of ultrasonic testing for determining the elastic properties of RPC. Comparison between static modulus of elasticity and ultrasonic modulus measurements is presented. A system for determining elastic moduli as a quality control tool is discussed. The effect of curing conditions on ultrasonic velocities and resulting calculated moduli values is presented and compared with traditional measurement methods.

Washer, Glenn; Fuchs, Paul; Graybeal, Benjamin; Rezaizadeh, Ali

2004-02-01

259

Nondestructive Analysis of Telescope Surfaces and Coatings  

NASA Astrophysics Data System (ADS)

The Department of Physics and Astronomy at Western Kentucky University has a Large Chamber Scanning Electron Microscope (LCSEM) available for materials analysis. As one of 10 in the world, the capability exists for nondestructive analysis of large samples. Currently we are investigating using the LCSEM to quantify reflectivity and long-term integrity for large segments of optical elements and detectors for ground and space-based environments. Comparisons of reflectance ratios as a function of surface roughness for Al-Coated optical mirrors may be confirmed with the LCSEM. Long-term structural integrity of Al-coated thinned mirror segments at ground-based facilities due to weather (oxidation) and spaced-based high-radiation environments can be investigated. Fatigue behavior of these metallic films from active/adaptive actuation will be simulated using the LCSEM. New research possibilities across a broad multidisciplinary spectrum will be key to the success of the LCSEM facility. These partnerships will lead to the development of new and existing technologies.

Scott, Julie; Kintzel, Edward; Strolger, Louis; Wolff, Schuyler

2010-10-01

260

Noninvasive, nondestructive approaches to cell bioenergetics.  

PubMed Central

To demonstrate the feasibility of using NMR spectra of human limbs and larger animals for continuous, noninvasive, nondestructive evaluation of cell bioenergetics, we have constructed a relatively simple and inexpensive 31P NMR apparatus. This apparatus consists of an 18-cm (7-in.) bore superconducting magnet and appropriate transmit-receive components for Fourier transform NMR. The principal signals observed by this instrument in the tissues are due to phosphocreatine and inorganic phosphate. The apparatus can be used to detect tissue normoxia and hypoxia. The large phosphocreatine/phosphate ratio (greater than 10:1), and the low phosphate signal from normoxic tissue (approximately 10% of the phosphocreatine signal from brain and human skeletal tissue) make an increased phosphate peak a very sensitive indicator of tissue hypoxia. Direct experiments on the human forearm and leg and the brains of dog and rabbit suggest the applicability of 31P NMR to humans and animals. This method and optical methods can both be used for quantitative determination of oxygen delivery to tissue, function of mitochondria, and the coupling of bioenergetic processes to functional activity in skeletal tissue and brain. Images PMID:6938983

Chance, B; Eleff, S; Leigh, J S

1980-01-01

261

Noninvasive, Nondestructive Approaches to Cell Bioenergetics  

NASA Astrophysics Data System (ADS)

To demonstrate the feasibility of using NMR spectra of human limbs and larger animals for continuous, noninvasive, nondestructive evaluation of cell bioenergetics, we have constructed a relatively simple and inexpensive 31P NMR apparatus. This apparatus consists of an 18-cm (7-in.) bore superconducting magnet and appropriate transmit-receive components for Fourier transform NMR. The principal signals observed by this instrument in the tissues are due to phosphocreatine and inorganic phosphate. The apparatus can be used to detect tissue normoxia and hypoxia. The large phosphocreatine/phosphate ratio (>10:1), and the low phosphate signal from normoxic tissue (? 10% of the phosphocreatine signal from brain and human skeletal tissue) make an increased phosphate peak a very sensitive indicator of tissue hypoxia. Direct experiments on the human forearm and leg and the brains of dog and rabbit suggest the applicability of 31P NMR to humans and animals. This method and optical methods can both be used for quantitative determination of oxygen delivery to tissue, function of mitochondria, and the coupling of bioenergetic processes to functional activity in skeletal tissue and brain.

Chance, B.; Eleff, S.; Leigh, J. S.

1980-12-01

262

Antireflection/Passivation Step For Silicon Cell  

NASA Technical Reports Server (NTRS)

New process excludes usual silicon oxide passivation. Changes in principal electrical parameters during two kinds of processing suggest antireflection treatment almost as effective as oxide treatment in passivating cells. Does so without disadvantages of SiOx passivation.

Crotty, Gerald T.; Kachare, Akaram H.; Daud, Taher

1988-01-01

263

Immunochromatographic assay on thread.  

PubMed

Lateral-flow immunochromatographic assays are low-cost, simple-to-use, rapid tests for point-of-care screening of infectious diseases, drugs of abuse, and pregnancy. However, lateral flow assays are generally not quantitative, give a yes/no answer, and lack multiplexing. Threads have recently been proposed as a support for transporting and mixing liquids in lateral-flow immunochromatographic assays, but their use for quantitative high-sensitivity immunoassays has yet to be demonstrated. Here, we introduce the immunochromatographic assay on thread (ICAT) in a cartridge format that is suitable for multiplexing. The ICAT is a sandwich assay performed on a cotton thread knotted to a nylon fiber bundle, both of which are precoated with recognition antibodies against one target analyte. Upon sample application, the assay results become visible to the eye within a few minutes and are quantified using a flatbed scanner. Assay conditions were optimized, the binding curves for C-reactive protein (CRP) in buffer and diluted serum were established and a limit of detection of 377 pM was obtained. The possibility of multiplexing was demonstrated using three knotted threads coated with antibodies against CRP, osteopontin, and leptin proteins. The performance of the ICAT was compared with that of the paper-based and conventional assays. The results suggest that thread is a suitable support for making low-cost, sensitive, simple-to-use, and multiplexed diagnostic tests. PMID:22889381

Zhou, Gina; Mao, Xun; Juncker, David

2012-09-18

264

Spent-fuel assay performance and Monte Carlo Analysis of the Rensselaer slowing-down-time spectrometer  

Microsoft Academic Search

The slowing-down-time method for the nondestructive assay of light water reactor (LWR) spent fuel is under development at Rensselaer Polytechnic Institute. A series of assay measurements of an LWR fuel assembly replica were carried out at the Rensselaer lead slowing-down-time spectrometer facility by using [sup 238]U and [sup 232]Th threshold fission detectors and [sup 235]U and [sup 239]Pu probe chambers.

N. Abdurrahman; R. C. Block; D. R. Harris; R. E. Slovacek; Yong Doek Lee; F. Rodriguez-Vera

1993-01-01

265

Advanced analysis techniques for uranium assay  

SciTech Connect

Uranium has a negligible passive neutron emission rate making its assay practicable only with an active interrogation method. The active interrogation uses external neutron sources to induce fission events in the uranium in order to determine the mass. This technique requires careful calibration with standards that are representative of the items to be assayed. The samples to be measured are not always well represented by the available standards which often leads to large biases. A technique of active multiplicity counting is being developed to reduce some of these assay difficulties. Active multiplicity counting uses the measured doubles and triples count rates to determine the neutron multiplication (f4) and the product of the source-sample coupling ( C ) and the 235U mass (m). Since the 35U mass always appears in the multiplicity equations as the product of Cm, the coupling needs to be determined before the mass can be known. A relationship has been developed that relates the coupling to the neutron multiplication. The relationship is based on both an analytical derivation and also on empirical observations. To determine a scaling constant present in this relationship, known standards must be used. Evaluation of experimental data revealed an improvement over the traditional calibration curve analysis method of fitting the doubles count rate to the 235Um ass. Active multiplicity assay appears to relax the requirement that the calibration standards and unknown items have the same chemical form and geometry.

Geist, W. H. (William H.); Ensslin, Norbert; Carrillo, L. A. (Louis A.); Beard, C. A. (Carl A.)

2001-01-01

266

Cryogenic Storage Tank Non-Destructive Evaluation  

NASA Technical Reports Server (NTRS)

This slide presentation reviews the work in non-destructive evaluation (NDE) of cryogenic storage tanks. Four large cryogenic tanks, constructed in 1965 with perlite insulation in the annular regions, are of concern. The construction of the tanks, two Liquid Oxygen (LOX) and two Liquid Hydrogen (LH2), are described. The loss rate for the LOX tank at Pad A is slightly higher than that for the one at Pad B. The concerns for the LH2 tank at Pad B are that there is a significantly higher boil-off rate than that at Pad A, that there is mold growth, indicative of increased heat flow, that there is a long down-time needed for repairs, and that 3 of 5 full thermal cycles have been used on the Pad B LH2 tank. The advantages and disadvantages of thermal imaging are given. A detailed description of what is visible of the structures in the infra-red is given and views of the thermal images are included. Missing Perlite is given as the probable cause of the cold spot on the Pad B LH2 tank. There is no indications of problematic cold regions on the Pad A LH2 tank, as shown by the thermal images given in the presentation. There is definite indication of a cold region on the Pad A LOX tank. There is however concerns with thermal imaging, as thermal images can be significantly effected by environmental conditions, image differences on similar days but with different wind speeds. Other effects that must be considered include ambient temperature, humidity levels/dew, and cloud reflections

Arens, Ellen

2010-01-01

267

Passive Vaporizing Heat Sink  

NASA Technical Reports Server (NTRS)

A passive vaporizing heat sink has been developed as a relatively lightweight, compact alternative to related prior heat sinks based, variously, on evaporation of sprayed liquids or on sublimation of solids. This heat sink is designed for short-term dissipation of a large amount of heat and was originally intended for use in regulating the temperature of spacecraft equipment during launch or re-entry. It could also be useful in a terrestrial setting in which there is a requirement for a lightweight, compact means of short-term cooling. This heat sink includes a hermetic package closed with a pressure-relief valve and containing an expendable and rechargeable coolant liquid (e.g., water) and a conductive carbon-fiber wick. The vapor of the liquid escapes when the temperature exceeds the boiling point corresponding to the vapor pressure determined by the setting of the pressure-relief valve. The great advantage of this heat sink over a melting-paraffin or similar phase-change heat sink of equal capacity is that by virtue of the =10x greater latent heat of vaporization, a coolant-liquid volume equal to =1/10 of the paraffin volume can suffice.

Knowles, TImothy R.; Ashford, Victor A.; Carpenter, Michael G.; Bier, Thomas M.

2011-01-01

268

Passive Solar Is Common Sense.  

ERIC Educational Resources Information Center

A checklist of concepts concerning passive solar energy techniques. Many can be applied immediately to existing buildings, while others should be brought into the initial planning of buildings. (Author/MLF)

Robison, Rita

1979-01-01

269

Galaxy Zoo: passive red spirals  

Microsoft Academic Search

We study the spectroscopic properties and environments of red (or passive) spiral galaxies found by the Galaxy Zoo project. By carefully selecting face-on disc-dominated spirals, we construct a sample of truly passive discs (i.e. they are not dust reddened spirals, nor are they dominated by old stellar populations in a bulge). As such, our red spirals represent an interesting set

Karen L. Masters; Moein Mosleh; A. Kathy Romer; Robert C. Nichol; Steven P. Bamford; Kevin Schawinski; Chris J. Lintott; Dan Andreescu; Heather C. Campbell; Ben Crowcroft; Isabelle Doyle; Edward M. Edmondson; Phil Murray; M. Jordan Raddick; Anze Slosar; Alexander S. Szalay; Jan Vandenberg

2010-01-01

270

Assays without Borders  

Cancer.gov

CPTAC researchers partner with international labs to demonstrate the ability of Targeted mass spectrometry–based assays to reproducibly quantify Human proteins across labs, countries and continents in a recently published journal article.

271

Passive vapor extraction feasibility study  

SciTech Connect

Demonstration of a passive vapor extraction remediation system is planned for sites in the 200 West Area used in the past for the disposal of waste liquids containing carbon tetrachloride. The passive vapor extraction units will consist of a 4-in.-diameter pipe, a check valve, a canister filled with granular activated carbon, and a wind turbine. The check valve will prevent inflow of air that otherwise would dilute the soil gas and make its subsequent extraction less efficient. The granular activated carbon is used to adsorb the carbon tetrachloride from the air. The wind turbine enhances extraction rates on windy days. Passive vapor extraction units will be designed and operated to meet all applicable or relevant and appropriate requirements. Based on a cost analysis, passive vapor extraction was found to be a cost-effective method for remediation of soils containing lower concentrations of volatile contaminants. Passive vapor extraction used on wells that average 10-stdft{sup 3}/min air flow rates was found to be more cost effective than active vapor extraction for concentrations below 500 parts per million by volume (ppm) of carbon tetrachloride. For wells that average 5-stdft{sup 3}/min air flow rates, passive vapor extraction is more cost effective below 100 ppm.

Rohay, V.J.

1994-06-30

272

Microfluidic DNA hybridization assays  

Microsoft Academic Search

DNA hybridization is one of the most powerful techniques applied in diagnostic assays. Microfluidics provides a promising\\u000a means to analyse small sample volumes, reduce reagent consumption and cost, shorten processing time as well as develop fast,\\u000a sensitive and portable diagnostic tools. By coupling with the microfluidic technology, DNA hybridization assay can achieve\\u000a high sensitivity, enhance hybridization kinetics and decrease the

Xuan WengHai; Hai Jiang; Dongqing Li

273

Doped colorimetric assay liposomes  

DOEpatents

The present invention provides compositions comprising colorimetric assay liposomes. The present invention also provides methods for producing colorimetric liposomes and calorimetric liposome assay systems. In preferred embodiments, these calorimetric liposome systems provide high levels of sensitivity through the use of dopant molecules. As these dopants allow the controlled destabilization of the liposome structure, upon exposure of the doped liposomes to analyte(s) of interest, the indicator color change is facilitated and more easily recognized.

Charych, Deborah (Albany, CA); Stevens, Raymond C. (Albany, CA)

2001-01-01

274

NON-DESTRUCTIVE SOIL CARBON ANALYZER.  

SciTech Connect

This report describes the feasibility, calibration, and safety considerations of a non-destructive, in situ, quantitative, volumetric soil carbon analytical method based on inelastic neutron scattering (INS). The method can quantify values as low as 0.018 gC/cc, or about 1.2% carbon by weight with high precision under the instrument's configuration and operating conditions reported here. INS is safe and easy to use, residual soil activation declines to background values in under an hour, and no radiological requirements are needed for transporting the instrument. The labor required to obtain soil-carbon data is about 10-fold less than with other methods, and the instrument offers a nearly instantaneous rate of output of carbon-content values. Furthermore, it has the potential to quantify other elements, particularly nitrogen. New instrumentation was developed in response to a research solicitation from the U.S. Department of Energy (DOE LAB 00-09 Carbon Sequestration Research Program) supporting the Terrestrial Carbon Processes (TCP) program of the Office of Science, Biological and Environmental Research (BER). The solicitation called for developing and demonstrating novel techniques for quantitatively measuring changes in soil carbon. The report includes raw data and analyses of a set of proof-of-concept, double-blind studies to evaluate the INS approach in the first phase of developing the instrument. Managing soils so that they sequester massive amounts of carbon was suggested as a means to mitigate the atmospheric buildup of anthropogenic CO{sub 2}. Quantifying changes in the soils' carbon stocks will be essential to evaluating such schemes and documenting their performance. Current methods for quantifying carbon in soil by excavation and core sampling are invasive, slow, labor-intensive and locally destroy the system being observed. Newly emerging technologies, such as Laser Induced Breakdown Spectroscopy and Near-Infrared Spectroscopy, offer soil-carbon analysis; however, these also are invasive and destructive techniques. The INS approach permits quantification in a relatively large volume of soil without disrupting the measurement site. The technique is very fast and provides nearly instantaneous results thereby reducing the cost, and speeding up the rate of analysis. It also has the potential to cover large areas in a mobile scanning mode. These capabilities will significantly advance the tracking carbon sequestration and offer a tool for research in agronomy, forestry, soil ecology and biogeochemistry.

WIELOPOLSKI,L.MITRA,S.HENDREY,G.ORION,I.ROGERS,H.TORBERT,A.PRIOR,S.RUNION,B.

2004-02-01

275

Method and apparatus for nondestructive in vivo measurement of photosynthesis  

DOEpatents

A device for in situ, nondestructive measurement of photosynthesis in live plants and photosynthetic microorganisms is disclosed which comprises a Clark-type oxygen electrode having a substantially transparent cathode comprised of an optical fiber having a metallic grid microetched onto its front face and sides, an anode, a substantially transparent electrolyte film, and a substantially transparent oxygen permeable membrane. The device is designed to be placed in direct contact with a photosynthetic portion of a living plant, and nondestructive, noninvasive measurement of photosynthetic oxygen production from the plant can be taken by passing light through the fiber-optic cathode, transparent electroyte and transparent membrane, and onto the plant so that photosynthesis occurs. The oxygen thus produced by the plant is measured polargraphically by the electrode. The present invention allows for rapid, nondestructive measurements of photosynthesis in living plants in a manner heretofore impossible using prior art methods.

Greenbaum, Elias (Oak Ridge, TN)

1988-01-01

276

Method and apparatus for nondestructive in vivo measurement of photosynthesis  

DOEpatents

A device for in situ, nondestructive measurement of photosynthesis in live plants and photosynthetic microorganisms is disclosed which comprises a Clark-type oxygen electrode having a substantially transparent cathode comprised of an optical fiber having a metallic grid microetched onto its front face and sides, an anode, a substantially transparent electrolyte film, and a substantially transparent oxygen permeable membrane. The device is designed to be placed in direct contact with a photosynthetic portion of a living plant, and nondestructive, noninvasive measurement of photosynthetic oxygen production from the plant can be taken by passing light through the fiber-optic cathode, transparent electrolyte and transparent membrane, and onto the plant so that photosynthesis occurs. The oxygen thus produced by the plant is measured polarographically by the electrode. The present invention allows for rapid, nondestructive measurements of photosynthesis in living plants in a manner heretofore impossible using prior art methods. 6 figs.

Greenbaum, E.

1988-02-22

277

On-line nondestructive methods for examining fuel particles  

SciTech Connect

Tri-isotropic (TRISO) particle fuels are being considered for use in various advanced nuclear power reactors and about 15 billion of these small ({approx} 1 mm diameter) spheres are needed for a single fuel load. Current quality control methods are manual, often destructive of test specimens, and they are economically impractical for automated application at commercial scale. Replacing these methods with new nondestructive evaluation techniques, automated for higher speed, will make fuel production and reactor operation economically more attractive. This paper reports aspects of a project to develop and demonstrate nondestructive examination methods to detect and reject defective particles. The work explored adapting, developing, and demonstrating innovative nondestructive test methods to cost-effectively assure the quality of large percentages of the fuel particles. (authors)

Pardini, A.F.; Bond, L.J.; Good, M.S.; Bunch, K.J.; Sandness, G.A. [Pacific Northwest National Laboratory, P.O. Box 999, Richland, WA 99352 (United States); Hockey, R.L. [Applied Research Associates, 4300 San Mateo Blvd. NE, Suite A-220, Albuquerque, NM 87110 (United States); Saurwein, J.J. [General Atomics, 3550 General Atomics Court, San Diego, CA 92121 (United States); Gray, J.N. [Iowa State University, 215A ASC II, 1915 Scholl Road, Ames, IA 50011 (United States)

2007-07-01

278

On-Line Nondestructive Methods for Examining Fuel Particles  

SciTech Connect

Tri-isotropic (TRISO) particle fuels, being considered for use in various advanced nuclear power reactors, consist of sub-millimeter diameter uranium oxide spheres uniformly coated to prevent the release of fission products into the reactor. About 15 billion of these spheres are needed to fuel a single reactor. Current quality control (QC) methods are manual, can destroy test specimens, and are not economically feasible. Replacing these methods with nondestructive evaluation (NDE) techniques, automated for higher speed, will make fuel production and reactor operation economically feasible, considering the requirement for extremely large fuel particle throughput rates. This paper reports a project to develop and demonstrate nondestructive examination methods to detect and reject defective particles, and in particular progress made in the final year of a Nuclear Energy Research Initiative (NERI) project . The work explored adapting, developing, and demonstrating innovative nondestructive test methods to cost-effectively assure the quality of large percentages of the fuel particles.

Pardini, Allan F.; Bond, Leonard J.; Good, Morris S.; Bunch, Kyle J.; Sandness, Gerald A.; Hockey, Ronald L.; Saurwein, John J.; Gray, Joseph N.

2007-09-15

279

Microgravity Passive Phase Separator  

NASA Technical Reports Server (NTRS)

A new invention disclosure discusses a structure and process for separating gas from liquids in microgravity. The Microgravity Passive Phase Separator consists of two concentric, pleated, woven stainless- steel screens (25-micrometer nominal pore) with an axial inlet, and an annular outlet between both screens (see figure). Water enters at one end of the center screen at high velocity, eventually passing through the inner screen and out through the annular exit. As gas is introduced into the flow stream, the drag force exerted on the bubble pushes it downstream until flow stagnation or until it reaches an equilibrium point between the surface tension holding bubble to the screen and the drag force. Gas bubbles of a given size will form a front that is moved further down the length of the inner screen with increasing velocity. As more bubbles are added, the front location will remain fixed, but additional bubbles will move to the end of the unit, eventually coming to rest in the large cavity between the unit housing and the outer screen (storage area). Owing to the small size of the pores and the hydrophilic nature of the screen material, gas does not pass through the screen and is retained within the unit for emptying during ground processing. If debris is picked up on the screen, the area closest to the inlet will become clogged, so high-velocity flow will persist farther down the length of the center screen, pushing the bubble front further from the inlet of the inner screen. It is desired to keep the velocity high enough so that, for any bubble size, an area of clean screen exists between the bubbles and the debris. The primary benefits of this innovation are the lack of any need for additional power, strip gas, or location for venting the separated gas. As the unit contains no membrane, the transport fluid will not be lost due to evaporation in the process of gas separation. Separation is performed with relatively low pressure drop based on the large surface area of the separating screen. Additionally, there are no moving parts, and there are no failure modes that involve fluid loss. A patent application has been filed.

Paragano, Matthew; Indoe, William; Darmetko, Jeffrey

2012-01-01

280

Preparation of Small Well Characterized Plutonium Oxide Reference Materials and Demonstration of the Usefulness of Such Materials for Nondestructive Analysis  

SciTech Connect

Calibration of neutron coincidence and multiplicity counters for passive nondestructive analysis (NDA) of plutonium requires knowledge of the detector efficiency parameters. These are most often determined empirically. Bias from multiplication and unknown impurities may be incurred even with small plutonium metal samples. Five sets of small, pure plutonium metal standards prepared with well-known geometry and very low levels of impurities now contribute to determining accurate multiplication corrections. Recent measurements of these metal standards, with small but well-defined multiplication and negligible yield of other than fission neutrons, demonstrate an improved characterization and calibration of neutron coincidence/multiplicity counters. The precise knowledge of the mass and isotopic composition of each standard also contributes significantly to verifying the accuracy of the most precise calorimetry and gamma-ray spectroscopy measurements.

B.A. Guillen; S.T. Hsue; J.Y Huang; P.A. Hypes; S.M. Long; C.R. Rudy; P.A. Russo; J.E. Stewart; D.J. Temer

2003-01-01

281

Rapid and nondestructive measurement of labile Mn, Cu, Zn, Pb and As in DGT by using field portable-XRF.  

PubMed

The technique of diffusive gradients in thin films (DGT) is often employed to quantify labile metals in situ; however, it is a challenge to perform the measurements in-field. This study evaluated the capability of field-portable X-ray fluorescence (FP-XRF) to swiftly generate elemental speciation information with DGT. Biologically available metal ions in environmental samples passively preconcentrate in the thin films of DGT devices, providing an ideal and uniform matrix for XRF nondestructive detection. Strong correlation coefficients (r > 0.992 for Mn, Cu, Zn, Pb and As) were obtained for all elements during calibration. The limits of quantitation (LOQ) for the investigated elements of FP-XRF on DGT devices are 2.74 for Mn, 4.89 for Cu, 2.89 for Zn, 2.55 for Pb, and 0.48 for As (unit: ?g cm(-2)). When Pb and As co-existed in the solution trials, As did not interfere with Pb detection when using Chelex-DGT. However, there was a significant enhancement of the Pb reading attributed to As when ferrihydrite binding gels were tested, consistent with Fe-oxyhydroxide surfaces absorbing large quantities of As. This study demonstrates the value of the FP-XRF technique to rapidly and nondestructively detect the metals accumulated in DGT devices, providing a new and simple diagnostic tool for on-site environmental monitoring of labile metals/metalloids. PMID:23912422

Chen, Zheng; Williams, Paul N; Zhang, Hao

2013-09-01

282

Lateral flow strip assay  

DOEpatents

A lateral flow strip assay apparatus comprising a housing; a lateral flow strip in the housing, the lateral flow strip having a receiving portion; a sample collection unit; and a reagent reservoir. Saliva and/or buccal cells are collected from an individual using the sample collection unit. The sample collection unit is immersed in the reagent reservoir. The tip of the lateral flow strip is immersed in the reservoir and the reagent/sample mixture wicks up into the lateral flow strip to perform the assay.

Miles, Robin R. (Danville, CA); Benett, William J. (Livermore, CA); Coleman, Matthew A. (Oakland, CA); Pearson, Francesca S. (Livermore, CA); Nasarabadi, Shanavaz L. (Livermore, CA)

2011-03-08

283

Continuous nondestructive monitoring of microbial biofilms: A review of analytical techniques  

Microsoft Academic Search

A fundamental requirement for the understanding and control of biofilms is the continuous nondestructive monitoring of biofilm processes. This paper reviews research analytical techniques that monitor biofilm processes in a continuous nondestructive manner and that could also be modified for industrial applications. To be considered ‘continuous’ and ‘nondestructive’ for the purpose of this review a technique must: (a) function in

D E Nivens; RJ Palmer Jr; D C White

1995-01-01

284

Nondestructive evaluation of electron-beam braze joins  

Microsoft Academic Search

A nondestructive evaluation (NDE) program has been carried out using holographic interferometry, microradiography, and eddy current testing for the inspection of electron beam braze joining of dissimilar metals. Stainless steel tubing was joined to a gold-copper disk using a Cusil (copper\\/silver) brazing alloy. Holographic interferometry provided an indirect measure of strength by detecting the plastic deformation occurring as a result

D. M. Boyd; J. F. Shackelford; B. W. Maxfield; G. M. Taylor

1981-01-01

285

Microwave Aquametry: An Effective Tool for Nondestructive Moisture Sensing  

Microsoft Academic Search

Moisture content in solid, granular and pulverized materials is one of the most important material parameters during production, trading, processing and storage of those materials. Recent advances in application of microwave measuring techniques to nondestructive determination of moisture content are reviewed, with a special emphasis being put on a newly developed concept of a density-independent calibration. It is concluded that

Andrzej Kraszewski; Richard B. Russell

2001-01-01

286

Nondestructive Characterization of Adhesive Bonds from Guided Wave Data  

NASA Technical Reports Server (NTRS)

The critical role played by interface zones in the fracture and failure of composites and other bonded materials is well known. The existing nondestructive evaluation methods are generally not capable of yielding useful quantitative information of the strength of an interface.

Mal, A.; Lih, S-S.; Bar-Cohen, Y.

1994-01-01

287

Nondestructive Crack Detection in a Fuel System Component  

NASA Technical Reports Server (NTRS)

The presentation examines the background and objective of nondestructive crack detection, flow control valve assembly and poppet post flight evaluation, poppet properties. magnetic property characterization of lab data, NDE, eddy current inspection, simulation, eddy current criteria, poppet cycle testing and NDE criteria, and the use of ultrasonic surface wave for crack detection.

Koshti, Ajay; Ruffino, Norman; Wincheski, Russell; Prosser, William; Winfree, William; Russell, Richard; Bryson, Craig; Devries, Robert; Engel, James; Landy, James

2010-01-01

288

Nondestructive test determines overload destruction characteristics of current limiter fuses  

NASA Technical Reports Server (NTRS)

Nondestructive test predicts the time required for current limiters to blow /open the circuit/ when subjected to a given overload. The test method is based on an empirical relationship between the voltage rise across a current limiter for a fixed time interval and the time to blow.

Swartz, G. A.

1968-01-01

289

Evaluation of methods for nondestructive testing of brazed joints  

NASA Technical Reports Server (NTRS)

Evaluation of nondestructive methods of testing brazed joints reveals that ultrasonic testing is effective in the detection of nonbonds in diffusion bonded samples. Radiography provides excellent resolutions of void or inclusion defects, and the neutron radiographic technique shows particular advantage for brazing materials containing cadmium.

Kanno, A.

1968-01-01

290

Condensed matter physics for non-destructive 100 T magnets  

Microsoft Academic Search

Various topics in condensed matter physics are cited as potential beneficiaries of non-destructive 100T magnets now being designed. These include layered systems, metals, superconductors, semi-metals, narrow gap and doped semiconductors, as well as systems of spin-polarized superstructures, real space Cooper pairs, and bipolarons. An extensive bibliography is provided.

G. S. Boebinger; S. Brazovskii; L. J. Campbell

1998-01-01

291

AUTOMATION FOR NONDESTRUCTIVE INSPECTION OF AIRCRAFT M. W. Siegel*  

E-print Network

mobile robots as automated aids to operators of nondestructive inspection (NDI) equipment. We review that make small mobile robots the most attractive alternative for automated aids for NDI procedures. We by corrosion, which is particularly prevalent in warm moist climates. Cracks and corrosion, accelerated

Siegel, Mel

292

Combining multiple nondestructive inspection images with a generalized additive model  

Microsoft Academic Search

In this paper, multiple nondestructive inspection (NDI) images are combined with a generalized additive model to achieve a more precise and reliable assessment of hidden corrosion in aircraft lap joints. Two inspection techniques are considered in this study. One is the conventional multi-frequency eddy current testing technique and the other is the pulsed eddy current technique. To characterize the thickness

Zheng Liu; Pradeep Ramuhalli; Saeed Safizadeh; David S. Forsyth

2008-01-01

293

Nondestructive method for measuring residual stresses in metals, a concept  

NASA Technical Reports Server (NTRS)

Nondestructive direct measurement of residual surface stresses in metals can be made because metal under stress has a different electrochemical solution potential than in the unstressed condition. The method uses two matched electrolytic cells to cancel extraneous effects on the actual solution potential of the metal specimen.

Schwebel, C. D.

1968-01-01

294

Transversal nondestructive test principle for photonic crystal fibers  

Microsoft Academic Search

Photonic crystal fibers (PCF) exhibit many challenges with respect to production. One property of such fibers that make them more complicated than standard fibers is their cladding structure that consists of air holes. These holes are typically arranged in a periodic pattern formation. We propose a novel monitoring method for non-destructive and non-invasive characterization of hole diameter and hole spacing

Thorkild Sørensen; Jesper Glückstad; Anders Bjarklev

2003-01-01

295

Non-destructive test of turbine blade by SANS  

Microsoft Academic Search

Small Angle Neutron Scattering (SANS) was used to investigate, in a non-destructive way, the effect of a thermomechanical treatment on UDIMET 720 nickel superalloy, in order to study the evolution of the gamma' precipitation, connected to the strengthening of the material, which suffers a very high temperature and corrosive attack.

P. Bianchi; F. Carsughi; D. D'Angelo; M. Magnani; A. Olchini; F. Rustichelli; M. Stefanon

1989-01-01

296

Non-destructive test of turbine blade by SANS  

NASA Astrophysics Data System (ADS)

Small Angle Neutron Scattering (SANS) was used to investigate, in a non-destructive way, the effect of a thermomechanical treatment on UDIMET 720 nickel superalloy, in order to study the evolution of the ?' precipitation, connected to the strengthening of the material, which suffers a very high temperature and corrosive attack.

Bianchi, P.; Carsughi, F.; D'Angelo, D.; Magnani, M.; Olchini, A.; Rustichelli, F.; Stefanon, M.

1989-01-01

297

Nondestructive testing of plastics by means of holographic interferometry  

Microsoft Academic Search

Holographic interferometry was investigated as a method for nondestructive testing of flat sheets of glass-fiber reinforced plastics. Initially, the deformation behavior of faultless sheets was examined by means of holographic interferometry. The interferograms which resulted from various loading conditions (i.e., tensile load, bending) were compared to results obtained mathematically. The interferograms of faultless sheets were then compared to those of

K. Gruenewald; W. Fritzsch; A. V. Harnier; E. Roth

1975-01-01

298

Holographic nondestructive testing of low-modulus materials  

Microsoft Academic Search

A holographic nondestructive testing method based on mechanical loading is proposed for defect detection and characterization of low-modulus materials. Fringe spacing analysis is introduced which is based on the size and shape of a fringe anomaly obtained experimentally. The loading should produce a strain of about 300 x 10 exp -6. Fringe anomalies can be identified visually or by fringe-spacing

V. R. Ravindran; A. V. S. S. S. R. Sarma; V. U. Nair

1992-01-01

299

New generation holographic measurement system for industrial nondestructive testing  

Microsoft Academic Search

Advanced achievements in holographic and speckle interferometry, physics of solid-state lasers, digital recording and image processing have created real precondistions for a rising of holographic methods of diagnostics to qualitatively new level. In the present work the general concept of universal holographic system for nondestructive researches in industrial environment is considered and results of tests of some units of this

V. S. Gurevich; M. E. Gusev; V. I. Redkorechev; V. E. Gaponov; I. V. Alexeseenko; A. M. Isaev; A. N. Malov; Yu. N. Zaharov

2005-01-01

300

Holographic soundfield visualization for nondestructive testing of hot surfaces  

Microsoft Academic Search

Nondestructive testing (NDT) of near-surface component regions is of great importance, because functionality, loading capacity, and lifetime of components often depend on material condition and discontinuities (flaws) in these regions. It is therefore necessary to provide reliable and problem-matched testing techniques to monitor material condition and to detect relevant inhomogeneities. This especially is true of the NDT of hot surfaces

Horst-Artur Crostack; E. H. Meyer; Klaus-Juergen Pohl

1991-01-01

301

Nondestructive testing of composite materials by holographic interferometry  

Microsoft Academic Search

Techniques for the nondestructive testing of composites by holographic interferometry are discussed, and results from tests analyzing carbon\\/epoxy composites for two types of defects, resulting from the impact of steel rods and the introduction of mylar inhomogeneities, are presented. Holographic techniques for the interferometric real-time observation of the superposition of the object and the holographic image, and for the recording

J. Ebbeni; M.-A. de Smet

1987-01-01

302

Holographic nondestructive testing by an optically generated zone plate  

Microsoft Academic Search

An improvement for holographic nondestructive testing in the field of information processing is proposed. It makes use of an optically generated zone plate for obtaining an interferometric hologram of an object suffering a deformation. This allows quick data acquisition and can be used outside laboratory conditions. Experimental results are discussed, and a brief mathematical analysis from the point of view

N. Rodriguez; R. D. Torroba; Mario Gallardo; Mario Garavaglia

1986-01-01

303

Holographic nondestructive testing in bone growth disturbance studies  

Microsoft Academic Search

We used isolated radioulnar bones (fused radial and ulnar bones) of subadult European moose collected in various environmentally polluted areas of Finland. The bones were radiographed and holographic interference pictures, for holographic nondestructive testing (HNDT), were produced by using small caudocranial bending forces. The cortical index values were measured in the diaphyses and samples were taken for mineral studies from

Raimo V. J. Silvennoinen; Kaarlo Nygren; Mikhail G. Mozerov

1994-01-01

304

Review of holographic nondestruction evaluation at Lawrence Livermore National Laboratory  

SciTech Connect

At Lawrence Livermore National Laboratory two holographic facilities have been established for the technology transfer of holographic interferometry. This report is a review of the principles of holographic interferometry (HI) and the application of this technique to nondestructive evaluation. Simplified quantitative analysis using a coincident viewing and illumination optical arrangement are described.

Boyd, D.M.

1983-01-01

305

Large-diameter bacteriorhodopsin films for applications in nondestructive testing  

Microsoft Academic Search

Bacteriorhodopsin (BR) films with dimension of 100 mm X 100 mm have been developed for applications in non- destructive testing. Films made from the photochromic retinal protein BR have been successfully employed in a variety of optical applications. Among them holographic interferometry for non-destructive testing which is one of the applications where the aperture of the BR-films used for recording

Norbert A. Hampp; Arne Seitz; Thorsten Juchem; Dieter Oesterhelt

1999-01-01

306

Nondestructive quantitative stress characterization of wire rope and steel cables  

Microsoft Academic Search

This paper describes a new approach to nondestructive and quantitative characterization of residual and applied stress (absolute stress) on wire rope and steel cable. Examples are given from both field work as well as laboratory tests, including stress characterization of post-tensioning cables, bridge suspension cables, wire rope and thin strand steel wire. The approach is based on x-ray diffraction techniques.

Michael E. Brauss; James A. Pineault; M. Belassel; S. I. Teodoropol

1998-01-01

307

CSER-98-009: antech neutron multiplicity counter for nondestructive analysis  

SciTech Connect

The ANTECH neutron multiplicity counter is a portable nondestructive assay (NDA) instrument which measures plutonium content by counting fission neutrons in the presence of (a,n) neutrons. Neutrons from the (a,n) process are discriminated against through the use of coincidence counting. The instrument will be used for the purpose of determining inventory of plutonium in the Plutonium Finishing Plant (PFP). The portability of the instrument will facilitate this task by minimizing the necessity of transporting fissile material. The use of the Antech counter is approved based on the inherent safety of the containers to be assayed in that an acceptable margin of subcriticality has been demonstrated for all normal and credible abnormal conditions in accordance with HNF-PRO-537 (F, 1997). A summary of the results of the abnormal conditions are tabulated in Table 2. For foreseeable contingencies, the calculated k{sub eff}s are less than 0.95 after taking into account the calculational bias and statistical uncertainty equal to or larger than the 95% confidence level. This approval is based on the requirement that only one container is to be put in the counter at a time and in accordance with the other limits listed in section 1.4. The design of the current instrument conforms with the acceptability criteria which allow the other NDA detectors currently employed at the facility to be safely used.

GOLDBERG, H.J.

1999-05-12

308

Passive-solar retrofit concepts  

NASA Astrophysics Data System (ADS)

Four retrofit passive solar designs for single family dwellings are presented. The first design, for a house in Minnesota, involves insulating wall cavities and the attic with blown cellulose, reduction of infiltration, and installation of insulating shades on all windows. The second, for a house in Michigan, combines weatherization, a sunspace with clerestory, and a thermosiphoning collector. The third, for a house in Missouri, involves the addition of a large sunspace with a passive solar hot water preheater for a hot tub. The fourth, for a house in Indiana, combines intensive weatherization with a two story sunspace and thermal chimney addition. All designs are thoroughly illustrated.

1981-09-01

309

Passive solar energy in buildings  

SciTech Connect

Designing commercial, institutional and domestic buildings so that they reap the benefits of freely available solar energy, is explored fully. People have been orientating buildings to make use of sunlight since they first began to live in permanent dwellings. New techniques are now available for employing passive solar energy in the home. On a bigger scale, these and other techniques are also applicable to sophisticated modern buildings like offices and schools, for example to cut down on fossil fuel usage. An authoritative assessment of the potential for utilizing passive solar energy is ser out in six sections. Domestic dwellings, offices, and industrial, retail and service buildings are all covered.

O'Sullivan, P. (Welsh School of Architecture, UWIST, Cardiff (US))

1988-01-01

310

Kinetic tetrazolium microtiter assay  

NASA Technical Reports Server (NTRS)

A method for conducting an in vitro cell assay using a tetrazolium indicator is disclosed. The indicator includes a nonionic detergent which solubilizes a tetrazolium reduction product in vitro and has low toxicity for the cells. The incubation of test cells in the presence of zolium bromide and octoxynol (TRITON X-100) permits kinetics of the cell metabolism to be determined.

Pierson, Duane L. (inventor); Stowe, Raymond P. (inventor); Koeing, David W. (inventor)

1992-01-01

311

Infrared thermography as a nondestructive tool for materials characterisation and assessment  

NASA Astrophysics Data System (ADS)

Thermographic approaches, passive and active, are widely used due to the outstanding advantages that offer in a number of applications and particularly for the assessment of materials. Nonetheless, there are limitations; depending upon the approach used, as well as on the materials thermal, optical and physical properties, proper assessment (detection and/or quantification) is feasible. In thermal non-destructive evaluation (NDE), the active approach of infrared thermography where an excitation source, such as optical flash lamps, heat lamps, hot or cold air guns, etc., is employed with the intention of inducing thermal contrasts, has several applications. The temperature differences during the transient phase appear on the material surface and so detection of subsurface defects is possible (areas of different temperatures when compared to the sound part(s) due to the different thermal diffusivity). Since the heating or cooling features of the stimulus source are identifiable (in time and amplitude) by considering the time factor quantitative assessment is also feasible. However, when a material is heated, the thermal waves penetrate the material's surface. These waves are generally of various amplitudes and frequencies and are launched into the specimen, in a transient mode (i.e. transient thermography). In this work, different applications, employing transient thermographic testing, concerning the assessment of various composite materials and components are presented. Real time NDE is presented using various transient thermography approaches, i.e. pulsed thermography (PT), pulsed phase thermography (PPT) and/or thermal modelling (TM).

Avdelidis, N. P.; Gan, T.-H.; Ibarra-Castanedo, C.; Maldague, X. P. V.

2011-05-01

312

Passive infrared motion sensing technology  

Microsoft Academic Search

In the last 10 years passive IR based (8 to 12 microns) motion sensing has matured to become the dominant method of volumetric space protection and surveillance. These systems currently cost less than $25 to produce and yet use traditionally expensive IR optics, filters, sensors, and electronic circuitry. This IR application is quite interesting in that the volumes of systems

Alan P

1994-01-01

313

Passive solar energy in buildings  

Microsoft Academic Search

Designing commercial, institutional and domestic buildings so that they reap the benefits of freely available solar energy, is explored fully. People have been orientating buildings to make use of sunlight since they first began to live in permanent dwellings. New techniques are now available for employing passive solar energy in the home. On a bigger scale, these and other techniques

1988-01-01

314

Monitored passive-solar buildings  

NASA Astrophysics Data System (ADS)

Selected performance results from six monitored passive and hybrid solar heated buildings are presented. These employ: a two story trombe wall; a thermosyphoning solar air heater with rock bin storage; a greenhouse; a composite concrete and water trombe wall; two story sunspace; and, for a mobile/modular home, direct gain and roof pond.

Jones, R. W.

1982-06-01

315

Passive propulsion in vortex wakes  

Microsoft Academic Search

A dead fish is propelled upstream when its flexible body resonates with oncoming vortices formed in the wake of a bluff cylinder, despite being well outside the suction region of the cylinder. Within this passive propulsion mode, the body of the fish extracts sufficient energy from the oncoming vortices to develop thrust to overcome its own drag. In a similar

D. N. Beal; F. S. Hover; M. S. Triantafyllou; J. C. Liao; G. V. Lauder

2006-01-01

316

Passive margins through earth history  

NASA Astrophysics Data System (ADS)

Passive margins have existed somewhere on Earth almost continually since 2740 Ma. They were abundant at 1900-1890, 610-520, and 150-0 Ma, scarce at ca. 2445-2300, 1600-1000, and 300-275 Ma, and absent before ca. 3000 Ma and at 1740-1600. The fluctuations in abundance of passive margins track the first-order fluctuations of the independently derived seawater 87Sr/ 86Sr secular curve, and the compilation thus appears to be robust. The 76 ancient passive margins for which lifespans could be measured have a mean lifespan of 181 m.y. The world-record holder, with a lifespan of 590 m.y., is the Mesoproterozoic eastern margin of the Siberian craton. Subdivided into natural age groups, mean lifespans are 186 m.y. for the Archean to Paleoproterozoic, 394 m.y. for the Mesoproterozoic, 180 m.y. for the Neoproterozoic, 137 m.y. for the Cambrian to Carboniferous, and 130 m.y. for the Permian to Neogene. The present-day passive margins, which are not yet finished with their lifespans, have a mean age of 104 m.y. and a maximum age of 180 m.y. On average, Precambrian margins thus had longer, not shorter, lifespans than Phanerozoic ones—and this remains the case even discounting all post-300 Ma margins, most of which have time left. Longer lifespans deeper in the past is at odds with the widely held notion that the tempo of plate tectonics was faster in the Precambrian than at present. It is entirely consistent, however, with recent modeling by Korenaga [Korenaga, J., 2004. Archean geodynamics and thermal evolution of Earth. Archean Geodynamics and Environments, AGU Geophysical Monograph Series 164, 7-32], which showed that plate tectonics was more sluggish in the Precambrian. The abundance of passive margins clearly tracks the assembly, tenure, and breakup of Pangea. Earlier parts of the hypothesized supercontinent cycle, however, are only partly consistent with the documented abundance of passive margins. The passive-margin record is not obviously consistent with the proposed breakup of Nuna (Columbia), the assembly of Rodinia, or the assembly or breakup of the putative Pannotia. An alternative model is put forth involving (a) formation of two or more supercratons during the late Paleoproterozoic, (b) a Mesoproterozoic interval dominated by lateral accretion of arcs rather than by continental breakup and dispersal, (c) wholesale collision to form Rodinia by the end of the Mesoproterozoic, and (d) staged breakup of Rodinia through much of the Neoproterozoic.

Bradley, Dwight C.

2008-12-01

317

Citric Acid Passivation of Stainless Steel.  

National Technical Information Service (NTIS)

Passivation is a process for cleaning and providing corrosion protection for stainless steel. Currently, on Kennedy Space Center (KSC), only parts passivated with nitric acid are acceptable for use. KSC disposes of approximately 125gal of concentrated nit...

C. Carl, C. Larson, D. Yasensky, J. Reali

2010-01-01

318

HCI gesture tracking using wearable passive tags  

E-print Network

In this thesis. a wearable system is developed to track hand gestures with passive RFID sensor tags. This system was composed of an ultra-high frequency reader and small, passive, finger-worn tags powered by scavenged RFID ...

Bainbridge, Rachel M

2010-01-01

319

HIGH ENERGY DELAYED GAMMA SPECTROSCOPY FOR PLUTONIUM ASSAY OF SPENT REACTOR FUEL  

SciTech Connect

Nuclear safeguards requires accountancy of plutonium present in spent reactor fuels. Current non-destructive methods do not directly measure plutonium content but instead rely on indirect measurements that require operator declarations of the fuel history. Delayed gamma spectroscopy is one method being investigated which can overcome these limitations. Delayed gamma rays from fission depend on the isotopic fission yield of the fissile isotope, and thus can be used to fingerprint the isotopes undergoing fission. However, difficulties arise because of the intense background due to long lived fission radionuclides already present in the fuel. We report on progress on simulated measurements of the delayed gamma spectrum in the presence of this background, using neutrons from a D-T source thermalized in an interrogation chamber slipped over a fuel assembly. By focusing on delayed gammas in the 3 to 4 MeV range, the passive spectrum becomes negligible, while allowing the preferential attenuation of the passive background to acceptable levels.

Campbell, Luke W.; Smith, L. E.; Misner, Alex C.

2011-07-18

320

Rat mesentery angiogenesis assay.  

PubMed

The adult rat mesentery window angiogenesis assay is biologically appropriate and is exceptionally well suited to the study of sprouting angiogenesis in vivo [see review papers], which is the dominating form of angiogenesis in human tumors and non-tumor tissues, as discussed in invited review papers(1,2). Angiogenesis induced in the membranous mesenteric parts by intraperitoneal (i.p.) injection of a pro-angiogenic factor can be modulated by subcutaneous (s.c.), intravenous (i.v.) or oral (p.o.) treatment with modifying agents of choice. Each membranous part of the mesentery is translucent and framed by fatty tissue, giving it a window-like appearance. The assay has the following advantageous features: (i) the test tissue is natively vascularized, albeit sparsely, and since it is extremely thin, the microvessel network is virtually two-dimensional, which allows the entire network to be assessed microscopically in situ; (ii) in adult rats the test tissue lacks significant physiologic angiogenesis, which characterizes most normal adult mammalian tissues; the degree of native vascularization is, however, correlated with age, as discussed in(1); (iii) the negligible level of trauma-induced angiogenesis ensures high sensitivity; (iv) the assay replicates the clinical situation, as the angiogenesis-modulating test drugs are administered systemically and the responses observed reflect the net effect of all the metabolic, cellular, and molecular alterations induced by the treatment; (v) the assay allows assessments of objective, quantitative, unbiased variables of microvascular spatial extension, density, and network pattern formation, as well as of capillary sprouting, thereby enabling robust statistical analyses of the dose-effect and molecular structure-activity relationships; and (vi) the assay reveals with high sensitivity the toxic or harmful effects of treatments in terms of decreased rate of physiologic body-weight gain, as adult rats grow robustly. Mast-cell-mediated angiogenesis was first demonstrated using this assay(3,4). The model demonstrates a high level of discrimination regarding dosage-effect relationships and the measured effects of systemically administered chemically or functionally closely related drugs and proteins, including: (i) low-dosage, metronomically administered standard chemotherapeutics that yield diverse, drug-specific effects (i.e., angiogenesis-suppressive, neutral or angiogenesis-stimulating activities(5)); (ii) natural iron-unsaturated human lactoferrin, which stimulates VEGF-A-mediated angiogenesis(6), and natural iron-unsaturated bovine lactoferrin, which inhibits VEGF-A-mediated angiogenesis(7); and (iii) low-molecular-weight heparin fractions produced by various means(8,9). Moreover, the assay is highly suited to studies of the combined effects on angiogenesis of agents that are administered systemically in a concurrent or sequential fashion. The idea of making this video originated from the late Dr. Judah Folkman when he visited our laboratory and witnessed the methodology being demonstrated. Review papers (invited) discussing and appraising the assay Norrby, K. In vivo models of angiogenesis. J. Cell. Mol. Med. 10, 588-612 (2006). Norrby, K. Drug testing with angiogenesis models. Expert Opin. Drug. Discov. 3, 533-549 (2008). PMID:21712799

Norrby, Klas C

2011-01-01

321

Multidimensional passive sampled Port-Hamiltonian systems  

Microsoft Academic Search

Passivity of virtual environments running in discrete time is a sufficient condition for stability of the system. The framework for passive sampled Port-Hamiltonian systems allows multi-dimensional virtual environments exhibiting internal dynamic behavior to be computed on a discrete medium in a passive manner. It is shown that a causality analysis is required in the framework to detect if any of

Michel Franken; Rob Reilink; Sarthak Misra; Stefano Stramigioli

2010-01-01

322

Treat mine water using passive methods  

Microsoft Academic Search

Passive treatment represents an alternative to conventional chemical treatment of coal mine drainage. When successful, passive systems require less investment, less maintenance and usually are less expensive than conventional chemical treatment systems. As a result, during the last seven years, more than 500 passive systems have been constructed in the United States to treat coal mine drainage. Some exist as

R. L. P. Kleinmann; R. S. Hedin

1993-01-01

323

Development of Verbal Passive in Williams Syndrome  

ERIC Educational Resources Information Center

Purpose: To experimentally investigate knowledge of passives of actional ("hold") and psychological ("love") verbs in children with Williams syndrome (WS). Passives are usually reported to be in line with mental age in WS. However, studies usually focus on passives of actional verbs only. Method: Twenty-six children with WS, ages 6-16, and 3…

Perovic, Alexandra; Wexler, Kenneth

2010-01-01

324

User evaluation study of passive solar residences  

SciTech Connect

Speculation exists regarding the readiness of various passive techniques for commercialization and the market potential for residential applications. This paper discusses the preliminary findings of a market assessment study designed to document user experiences with passive solar energy. Owners and builders of passive solar homes were interviewed and asked to comment on personal experiences with their homes.

Towle, S.

1980-03-01

325

Passive control techniques in earthquake engineering  

Microsoft Academic Search

Significant progress has been made in the development of passive control techniques in earthquake (EQ) engineering during the last two decades. Today, the most successful passive structural control technique in earthquake engineering is base isolation. Following the successful history of implementation of base isolation technology, passive energy dissipation devices are currently making inroads. In this paper a simple comparison of

Simon Kim

1995-01-01

326

Passive solar design handbook. Volume 3: Passive solar design analysis  

NASA Astrophysics Data System (ADS)

Simple analytical methods concerning the design of passive solar heating systems are presented with an emphasis on the average annual heating energy consumption. Key terminology and methods are reviewed. The solar load ratio (SLR) is defined, and its relationship to analysis methods is reviewed. The annual calculation, or Load Collector Ratio (LCR) method, is outlined. Sensitivity data are discussed. Information is presented on balancing conservation and passive solar strategies in building design. Detailed analysis data are presented for direct gain and sunspace systems, and details of the systems are described. Key design parameters are discussed in terms of their impact on annual heating performance of the building. These are the sensitivity data. The SLR correlations for the respective system types are described. The monthly calculation, or SLR method, based on the SLR correlations, is reviewed. Performance data are given for 9 direct gain systems and 15 water wall and 42 Trombe wall systems.

Jones, R. W.; Bascomb, J. D.; Kosiewicz, C. E.; Lazarus, G. S.; McFarland, R. D.; Wray, W. O.

1982-07-01

327

Mathematical models applied in inductive non-destructive testing  

NASA Astrophysics Data System (ADS)

Non-destructive testing are the wide group of investigative methods of non-homogenous material. Methods of computer tomography, ultrasonic, magnetic and inductive methods still developed are widely applied in industry. In apparatus used for non-destructive tests, the analysis of signals is made on the basis of complex system answers. The answer is linearized due to the model of research system. In this paper, the authors will discuss the applications of the mathematical models applied in investigations of inductive magnetic materials. The statistical models and other gathered in similarity classes will be taken into consideration. Investigation of mathematical models allows to choose the correct method, which in consequence leads to precise representation of the inner structure of examined object. Inductive research of conductive media, especially those with ferromagnetic properties, are run with high frequency magnetic field (eddy-currents method), which considerably decrease penetration depth.

Wac-Wlodarczyk, A.; Goleman, R.; Czerwinski, D.; Gizewski, T.

328

Non-destructive NIR FT Raman analysis of plants  

NASA Astrophysics Data System (ADS)

Non-destructive analyses of animal and plant cells and tissues by 'classical' Raman spectroscopy with excitation in the visible range have not been possible since the samples are destroyed photochemically or their fluorescence conceals the Raman spectra completely. When excited with the Nd:YAG laser line at 1064 nm fluorescence-free Raman spectra of animal or plant cells and tissues can be recorded without special preparation. In this paper we concentrate on plants and its constituents: essential oils, natural dyes, flavors, spices, alkaloids and fibers can be characterized. The spectra allow the observation of biochemical processes, to observe the distribution of natural products, application to taxonomy, optimizing plant breeding, the harvesting time and control of food—everything non-destructively in living plants!

Schrader, B.; Klump, H. H.; Schenzel, K.; Schulz, H.

1999-10-01

329

Nondestructive Damage Evaluation in Ceramic Matrix Composites for Aerospace Applications  

PubMed Central

Infrared thermography (IRT) and acoustic emission (AE) are the two major nondestructive methodologies for evaluating damage in ceramic matrix composites (CMCs) for aerospace applications. The two techniques are applied herein to assess and monitor damage formation and evolution in a SiC-fiber reinforced CMC loaded under cyclic and fatigue loading. The paper explains how IRT and AE can be used for the assessment of the material's performance under fatigue. IRT and AE parameters are specifically used for the characterization of the complex damage mechanisms that occur during CMC fracture, and they enable the identification of the micromechanical processes that control material failure, mainly crack formation and propagation. Additionally, these nondestructive parameters help in early prediction of the residual life of the material and in establishing the fatigue limit of materials rapidly and accurately. PMID:23935428

Dassios, Konstantinos G.; Kordatos, Evangelos Z.; Aggelis, Dimitrios G.; Matikas, Theodore E.

2013-01-01

330

Non-destructive examination system of vitreous body  

NASA Astrophysics Data System (ADS)

Eyeball plays a quite important role in acquiring the vision. Vitreous body occupies the largest part of the eyeball and consists of biological, elastic, transparent, gel materials. In the present medical examination, the non-destructive examination method of the vitreous body has not been well established. Here, we focus on an application of dynamic light scattering to this topic. We tried to apply our lab-made apparatus, scanning microscopic light scattering (SMILS), which was specially designed for observing the nanometer-scale network structure in gel materials. In order to examine the vitreous body using SMILS method, a commercial apparatus, nano Partica (Horiba Co. Ltd.) was also customized. We analyzed vitreous body using both the SMILS and the customized nano Partica. We successfully examined the vitreous bodies of healthy pigs in non-destructive way.

Shibata, Takuma; Gong, Jin; Watanabe, Yosuke; Kabir, M. Hasnat; Masato, Makino; Furukawa, Hidemitsu; Nishitsuka, Koichi

2014-04-01

331

Non-destructive techniques based on eddy current testing.  

PubMed

Non-destructive techniques are used widely in the metal industry in order to control the quality of materials. Eddy current testing is one of the most extensively used non-destructive techniques for inspecting electrically conductive materials at very high speeds that does not require any contact between the test piece and the sensor. This paper includes an overview of the fundamentals and main variables of eddy current testing. It also describes the state-of-the-art sensors and modern techniques such as multi-frequency and pulsed systems. Recent advances in complex models towards solving crack-sensor interaction, developments in instrumentation due to advances in electronic devices, and the evolution of data processing suggest that eddy current testing systems will be increasingly used in the future. PMID:22163754

García-Martín, Javier; Gómez-Gil, Jaime; Vázquez-Sánchez, Ernesto

2011-01-01

332

Nondestructive damage evaluation in ceramic matrix composites for aerospace applications.  

PubMed

Infrared thermography (IRT) and acoustic emission (AE) are the two major nondestructive methodologies for evaluating damage in ceramic matrix composites (CMCs) for aerospace applications. The two techniques are applied herein to assess and monitor damage formation and evolution in a SiC-fiber reinforced CMC loaded under cyclic and fatigue loading. The paper explains how IRT and AE can be used for the assessment of the material's performance under fatigue. IRT and AE parameters are specifically used for the characterization of the complex damage mechanisms that occur during CMC fracture, and they enable the identification of the micromechanical processes that control material failure, mainly crack formation and propagation. Additionally, these nondestructive parameters help in early prediction of the residual life of the material and in establishing the fatigue limit of materials rapidly and accurately. PMID:23935428

Dassios, Konstantinos G; Kordatos, Evangelos Z; Aggelis, Dimitrios G; Matikas, Theodore E

2013-01-01

333

Uranium holdup in concrete floors: a comparison of nondestructive methods  

SciTech Connect

In 1978, Babcock and Wilcox ceased operations at its high-enriched uranium conversion facility in Apollo, Pennsylvania. Incorporated in the Company's action was the responsibility to clean up, recover and/or identify any an all uranium that might be held up in processing equipment, piping, and the building. By 1980, most of the historical inventory difference had been recovered from the equipment and piping, which had been removed from the plant. It was anticipated that over the 20-yr history of this facility, some special nuclear material (SNM) would be embedded in the floors of the building. The objective of this work was to develop a method to measure this material nondestructively and as accurately as possible. This paper illustrates two nondestructive methods used at the Apollo facility and then presents a comparison of the NDA to the results of destructive recovery.

Hardt, T.L.; Dedo, M.P.

1986-01-01

334

Materials and Nondestructive Evaluation Laboratoriers: User Test Planning Guide  

NASA Technical Reports Server (NTRS)

The Materials and Nondestructive Evaluation Laboratory process, milestones and inputs are unknowns to first-time users. The Materials and Nondestructive Evaluation Laboratory Planning Guide aids in establishing expectations for both NASA and non- NASA facility customers. The potential audience for this guide includes both internal and commercial spaceflight hardware developers. It is intended to assist their project engineering personnel in materials analysis planning and execution. Material covered includes a roadmap of the analysis process, roles and responsibilities of facility and user, major milestones, facility capabilities, and inputs required by the facility. Samples of deliverables, products, and inputs necessary to define scope of analysis, cost, and schedule are included as an appendix to the guide.

Schaschl, Leslie

2011-01-01

335

Non-destructive metallurgical analysis of astrolabes utilizing synchrotron radiation.  

SciTech Connect

From the experiments performed it is possible to determine a wide range of information about the metallurgy of the astrolabes studied. It was found that different brass alloys were used for components that were cast and those that were mechanically deformed. Chemical composition, forming history, and thickness measurements are all determined non-destructively, illustrating that this technique could be useful for many applications with metal artifact analysis where non-intrusive methods are required.

Newbury, B.; Stephenson, B.; Almer, J. D.; Notis, M.; Haeffner, D. R.; Slade Cargill, G., III

2002-05-22

336

Federal laboratory nondestructive testing research and development applicable to industry  

SciTech Connect

This document presents the results of a survey of nondestructive testing (NDT) and related sensor technology research and development (R and D) at selected federal laboratories. Objective was to identify and characterize NDT activities that could be applied to improving energy efficiency and overall productivity in US manufacturing. Numerous federally supported R and D programs were identified in areas such as acoustic emissions, eddy current, radiography, computer tomography and ultrasonics. A Preliminary Findings Report was sent to industry representatives, which generated considerable interest.

Smith, S.A.; Moore, N.L.

1987-02-01

337

Magnetic nondestructive technology for detection of tempered martensite embrittlement  

NASA Astrophysics Data System (ADS)

A nondestructive eddy current technique is used to evaluate tempered martensite embrittlement in 4340 AISI steels after quench and tempering in the range 240-550 °C. A relation between the responses of the magnetic induction (normalized impedance of the coil) and destructive Charpy impact test results has been established. The study shows that the eddy current method could be used to separate brittle parts due to the microstructure changes.

Kashefi, Mehrdad; Rafsanjani, Ali; Kahrobaee, Saeed; Alaee, Moeen

2012-11-01

338

Nondestructive testing using nonlinear optically based smart-pixel processors  

Microsoft Academic Search

Summary form only given. There is an on-going need in the commercial sector to rapidly and nondestructively inspect components, in situ and in situ, under harsh in-factory and field-testing conditions. To motivate this need, we cite below three such examples in rather diverse industrial applications. This will be followed by how optics and, more specifically, how so-called “smart-pixel processors”, can

David M. Pepper

1994-01-01

339

Brighter Screens for Nondestructive Digital X-ray Radiography  

Microsoft Academic Search

Fine resolution, bright X-ray screens are needed for digital radiography and material characterization at the Y-12 National Security Complex (Y-12). Current technology is simply not adequate for transferring high-energy X-ray images to visible light for demanding digital applications. Low energy radiography and especially emerging tomographic technologies are severely hampered for Y-12 nondestructive evaluation (NDE) applications by dim screens with poor

Miller Jr. A. C; Z. W. Bell; D. A. Carpenter

2003-01-01

340

Non-destructive speckle interferometry diagnosis method for art conservation  

Microsoft Academic Search

We describe a field non-destructive Digital Speckle Pattern Interferometry diagnosis method to be applied in art conservation works, using as the light source a home-made single-frequency pulsed micro-laser oscillator-amplifier system. The green nanosecond laser-pulses are directed towards an interferometer set-up, where a beam splitter cube divides the incoming beam to define the object, respectively the reference beams. The object beam

Vivi Tornari; Y. Orphanos; R. Dabu; C. Blanaru; A. Stratan; D. Ursu

2007-01-01

341

X- and gamma-ray tomography for nondestructive material testing  

Microsoft Academic Search

Various apparatus for x and (gamma) -ray computed tomography (CT) have been constructed by us during the last 20 years, with the aim of producing simple and low-cost systems for nondestructive testing. The first one was constructed in 1980 and used an Am241 radioactive source emitting 59.6 keV (gamma) -rays and a single NaI(Tl)-x ray detector. Successively, the radioactive source

Roberto Cesareo; Antonio Brunetti; Ricardo T. Lopes; Gianfranco Galli; Donepudi V. Rao; Alfredo Castellano; Giovanni E. Gigante; Sergio Mascarenhas; Rene Robert; Vitoldo S. Filho; Marco Gilardoni; Hamilton P. da Silva; Piero Q. Colosso

1999-01-01

342

Nondestructive Evaluation of Ceramic Candle Filters Using Vibration Response  

SciTech Connect

This study aims at the development of an effective nondestructive evaluation technique to predict the remaining useful life of a ceramic candle filter during a power plant's annual maintenance shutdown. The objective of the present on-going study is to establish the vibration signatures of ceramic candle filters at varying degradation levels due to different operating hours, and to study the various factors involving the establishment of the signatures.

Chen, Roger H. L.; Kiriakidis, Alejandro C.; Peng, Steve W.

1997-07-01

343

Large area terahertz imaging and non-destructive evaluation applications  

Microsoft Academic Search

Abstract: Terahertz (THz) imaging,is being adopted for non-destructive evaluation (NDE) applications in aerospace and other government,and industrial settings [1-3]. NASA is currently employing ,THz reflection NDE to examine ,the space shuttle external tank sprayed on foam insulation (SOFI) for voids and disbonds. Homeland security applications such as the inspection of personnel[2], the detection of concealed explosives[2], biological agents, chemical weapons,

David Zimdars; Jeffrey S. White; G. stuk; A. chernovsky; G. Fichter; S. Williamson

2006-01-01

344

Development of nondestructive evaluation methods for ceramic coatings  

Microsoft Academic Search

Various nondestructive evaluation (NDE) technologies are being developed to advance the knowledge of ceramic coatings for components in the hot gas-path of advanced, low-emission gas-fired turbine engines. The ceramic coating systems being studied by NDE include thermal barrier coatings (TBCs) and environmental barrier coatings (EBCs). TBCs are under development for vanes, blades and combustor liners to allow hotter gas path

W. A. Ellingson; C. Deemer; J. G. Sun; S. Erdman; D. Muliere; B. Wheeler

2007-01-01

345

Non-destructive ultrasonic measurements of case depth. [in steel  

NASA Technical Reports Server (NTRS)

Two ultrasonic methods for nondestructive measurements of the depth of a case-hardened layer in steel are described. One method involves analysis of ultrasonic waves diffused back from the bulk of the workpiece. The other method involves finding the speed of propagation of ultrasonic waves launched on the surface of the work. Procedures followed in the two methods for measuring case depth are described.

Flambard, C.; Lambert, A.

1978-01-01

346

Use of acoustical holography in nondestructive inspection (review)  

SciTech Connect

A review of works devoted to the use of the acoustical holography method for nondestructive inspection of materials and structures is given. The basic methods in which the acoustical holography method is used and the resolving capacity and area of use of holographic systems are considered. The accuracy of determination of the dimensions and orientation of defects wit h the use of acoustical holography is discussed.

Badalyan, V.G.

1988-03-01

347

New generation holographic measurement system for industrial nondestructive testing  

NASA Astrophysics Data System (ADS)

Advanced achievements in holographic and speckle interferometry, physics of solid-state lasers, digital recording and image processing have created real precondistions for a rising of holographic methods of diagnostics to qualitatively new level. In the present work the general concept of universal holographic system for nondestructive researches in industrial environment is considered and results of tests of some units of this equipment are presented.

Gurevich, V. S.; Gusev, M. E.; Redkorechev, V. I.; Gaponov, V. E.; Alexeseenko, I. V.; Isaev, A. M.; Malov, A. N.; Zaharov, Yu. N.

2005-06-01

348

Portable shearing TV holography apparatus for nondestructive testing  

NASA Astrophysics Data System (ADS)

A portable phase shifting shearing TV-holography apparatus for non-destructive testing is presented in this paper. This apparatus has been utilized in the inspection of large area aluminum coated honeycomb structure of aeronautical composite for off-stick defect testing. The working principle and the configuration of the system are described. The structure will be detailed. Satisfactory result have been obtained with this system. Wrapped defect phase pattern will be shown.

Fan, Hua; Ngoi, Bryan K. A.; Tan, Yushan

1999-11-01

349

The Effects of Stress Mitigation on Nondestructive Examination  

SciTech Connect

Ultrasonic volumetric and eddy current and visual profile surface inspections of the completed weld securing the outer lid of the Yucca Mountain waste package are required after stress mitigation. However, the technique implemented may affect the ability of the different evaluation techniques to properly characterize the completed weld. An evaluation was performed to determine the extent the nondestructive evaluation techniques are affected by two candidate mitigation processes: controlled plasticity burnishing and laser peening. This report describes the work performed and summarizes the results.

Dennis C. Kunerth; Eric D. Larsen; Timothy R. Mcjunkin; Arthur D. Watkins

2004-08-01

350

Non-destructive evaluation of composite materials using ultrasound  

NASA Technical Reports Server (NTRS)

Investigation of the nondestructive evaluation of advanced composite-laminates is summarized. Indices derived from the measurement of fundamental acoustic parameters are used in order to quantitatively estimate the local material properties of the laminate. The following sections describe ongoing studies of phase insensitive attenuation measurements, and discuss several phenomena which influences the previously reported technique of polar backscatter. A simple and effective programmable gate circuit designed for use in estimating attenuation from backscatter is described.

Miller, J. G.

1984-01-01

351

Myths in passive solar design  

SciTech Connect

For years passive solar design principles have been perpetuated without being reexamined or questioned regarding their relevance in the context of new materials and constructions. Rarely does an architect get quantitative feedback on system or concept performance after the building is built. The result has been the perpetuation of beliefs among conference papers, text books and popular articles, all too often based only on belief. In this paper examples of premises which likely deserve to be kept passive rather than acted on are challenged. Designers are encouraged to ask three questions when applying a commonly held rule or assumption: Does it address the right issue? Does it apply, given the properties of new components and materials? If the premise is violated, how badly is comfort or the energy balance affected? Examples taken from monitoring and sensitivity studies illustrate the importance of asking `stupid` questions. 9 refs., 5 figs.

Hastings, S.R. [Swiss Federal Inst. of Technology, Zuerich (Switzerland)] [Swiss Federal Inst. of Technology, Zuerich (Switzerland)

1995-12-31

352

Biosensors: Viruses for ultrasensitive assays  

NASA Astrophysics Data System (ADS)

A three-dimensional assay based on genetically engineered viral nanoparticles and nickel nanohairs can detect much lower levels of protein markers associated with heart attacks than conventional assays.

Donath, Edwin

2009-04-01

353

Permeation prediction of M100240 using the parallel artificial membrane permeability assay  

Microsoft Academic Search

Purpose: Kansy et al (5) first introduced the Parallel artificial membrane permeation assay (PAMPA) in 1998. In this system, the permeability through a membrane formed by a mixture of lecithin and an inert organic solvent on a filter support is assessed. PAMPA shows definite trends in the ability of molecules to permeate membranes by transcellular passive diffusion. Its simplicity, low

Kin-Kai Hwang; Nancy E Martin; Lan Jiang; Chengyue Zhu

354

Workshop 1: Passive solar systems  

NASA Astrophysics Data System (ADS)

The design of a solar house for a latitude of 50 degrees north in Northern Europe is discussed. An evaluation of a 500 cubic meter house and a computerized simulation of a 350 cubic meter house are given. It was found that the heating demand of a poorly insulated house may be decreased by 70 to 75% by means of an extensive insulation; new buildings should be extensively insulated; passive solar energy utilization is usually not cost effective.

Schneider, M.; Schreitmueller, K. R.

1982-11-01

355

Passive Neutron Detection at Borders  

SciTech Connect

Radiation portal monitor systems have been deployed to screen for illicit trafficking of radioactive materials at international border crossings. This report reviews some of the neutron detection requirements and capabilities of passive detection systems used for such applications. Simulations show the effects of cargo materials on neutron spectra, different detector geometries, using a large-array of neutron detectors, and the effects of backgrounds including “ship effect” neutrons.

Kouzes, Richard T.; Siciliano, Edward R.; Ely, James H.; Keller, Paul E.; McConn, Ronald J.

2008-03-01

356

Evaluation of Alternate Surface Passivation Methods (U)  

SciTech Connect

Stainless steel containers were assembled from parts passivated by four commercial vendors using three passivation methods. The performance of these containers in storing hydrogen isotope mixtures was evaluated by monitoring the composition of initially 50% H{sub 2} 50% D{sub 2} gas with time using mass spectroscopy. Commercial passivation by electropolishing appears to result in surfaces that do not catalyze hydrogen isotope exchange. This method of surface passivation shows promise for tritium service, and should be studied further and considered for use. On the other hand, nitric acid passivation and citric acid passivation may not result in surfaces that do not catalyze the isotope exchange reaction H{sub 2} + D{sub 2} {yields} 2HD. These methods should not be considered to replace the proprietary passivation processes of the two current vendors used at the Savannah River Site Tritium Facility.

Clark, E

2005-05-31

357

A Chemical Assay for Renin  

Microsoft Academic Search

The investigation of renal hypertension has led to the enzyme renin. At present renin can only be properly assayed by bioassay with a live animal which as been fitted in some manner with a device for measuring blood pressure. One common method is the rat assay. This assay requires careful anaesthesia, skilled surgical preparation of the animal, and several hours

Bruce B. McDonald

1968-01-01

358

Nondestructive Evaluation of Tissue Engineered Articular Cartilage Using Time-Resolved Fluorescence Spectroscopy and Ultrasound Backscatter Microscopy  

PubMed Central

The goal of this study is to evaluate the ability of a bimodal technique integrating time-resolved fluorescence spectroscopy (TRFS) and ultrasound backscatter microscopy (UBM) for nondestructive detection of changes in the biochemical, structural, and mechanical properties of self-assembled engineered articular cartilage constructs. The cartilage constructs were treated with three chemical agents (collagenase, chondroitinase-ABC, and ribose) to induce changes in biochemical content (collagen and glycosaminoglycan [GAG]) of matured constructs (4 weeks); and to subsequently alter the mechanical properties of the construct. The biochemical changes were evaluated using TRFS. The microstructure and the thickness of the engineered cartilage samples were characterized by UBM. The optical and ultrasound results were validated against those acquired via conventional techniques including collagen and GAG quantification and measurement of construct stiffness. Current results demonstrated that a set of optical parameters (e.g., average fluorescence lifetime and decay constants) showed significant correlation (p<0.05) with biochemical and mechanical data. The high-resolution ultrasound images provided complementary cross-section information of the cartilage samples morphology. Therefore, the technique was capable of nondestructively evaluating the composition of extracellular matrix and the microstructure of engineered tissue, demonstrating great potential as an alternative to traditional destructive assays. PMID:22010819

Responte, Donald; Xie, Hongtao; Liu, Jing; Fatakdawala, Hussain; Hu, Jerry; Athanasiou, Kyriacos A.

2012-01-01

359

SWEPP assay system version 2.0 software requirements specification  

SciTech Connect

The INEL Stored Waste Examination Pilot Plant (SWEPP) operations staff use nondestructive analysis methods to characterize the radiological contents of contact-handled radioactive waste containers. Containers of waste from Rocky Flats Environmental Technology Site and other DOE sites are currently stored at SWEPP. Before these containers can be shipped to WIPP, SWEPP must verify compliance with storage, shipping, and disposal requirements. One part of the SWEPP program measures neutron emissions from the containers and estimates the mass of Pu and other transuranic isotopes present. The code NEUT2 was originally used to perform data acquisition and reduction; the SWEPP Assay System (SAS) code replaced NEUT2 in early 1994. This document specifies the requirements for the SAS software as installed at INEL and was written to comply with RWMC (INEL Radioactive Waste Management Complex) quality requirements.

Matthews, S.D.; East, L.V.; Marwil, E.S.; Ferguson, J.J.

1996-06-01

360

Delayed Gamma-Ray Spectroscopy for Spent Nuclear Fuel Assay  

SciTech Connect

High-energy, beta-delayed gamma-ray spectroscopy is investigated as a non-destructive assay technique for the determination of plutonium mass in spent nuclear fuel. This approach exploits the unique isotope-specific signatures contained in the delayed gamma-ray emission spectra detected following active interrogation with an external neutron source. A high fidelity modeling approach is described that couples radiation transport, analytical decay/depletion, and a newly developed gamma-ray emission source reconstruction code. Initially simulated and analyzed was a “one-pass” delayed gamma-ray assay that focused on the long-lived signatures. Also presented are the results of an independent study that investigated “pulsed mode” measurements, to capture the more isotope-specific, short-lived signatures. Initial modeling results outlined in this paper suggest that delayed gamma-ray assay of spent nuclear fuel assemblies can be accomplished with a neutron generator of sufficient strength and currently available gamma-ray detectors.

Campbell, Luke W.; Hunt, Alan W.; Ludewigt, Bernhard A.; Mozin, Vladimir V.

2012-04-01

361

Time course of hepatitis A antibody production after active, passive and active/passive immunisation: the results are highly dependent on the antibody test system used.  

PubMed

Two commercially available automated test systems for hepatitis A antibody, HAVAB IMX (Abbott) and ENZYMUN Anti-HAV (Boehringer) were evaluated in a study of active, passive and active/passive immunisation against hepatitis A. The inactivated hepatitis A vaccine Epaxal Berna and the hepatitis A immunoglobulin preparation Globuman were products of the Swiss Serum and Vaccine Institute. Although both hepatitis A antibody test kits were standardised with the same international WHO standard hepatitis A immunoglobulin preparation, divergent results were obtained for the level of circulating hepatitis A antibody after vaccination. One month after the vaccination the mean geometric antibody titres were 315 mIU/ml after active, 253 mIU after active/passive and 22 mIU after passive immunisation when measured with the Enzymun assay. In the same sera 70 mIU/ml after active, 60 mIU after active/passive and 18 mIU after passive immunisation could be detected with the IMX test. Antibody avidity studies could not explain the differences obtained by the two test methods. The neutralization test is the standard method for the estimation of protection against hepatitis A. This test is not suitable for large series of serum samples, and enzyme immunoassays are indispensable for vaccination studies. To be suitable for monitoring antibody development in phase I and II clinical trials as well as in postmarketing studies, EIA tests for hepatitis A antibodies must be commercially available and of known sensitivity. The Enzymun anti-HAV test developed by Boehringer Mannheim (Germany) offers the possibility to measure antibody titres around the protective level of 20 mIU/ml which is reached by the passive immunisation with immunoglobulin preparations or within two weeks after active vaccination with an inactivated hepatitis A vaccine. The Abbott IMX test system is more useful for the detection of natural infections by the hepatitis A virus. PMID:8408443

Berger, R; Just, M; Althaus, B

1993-08-01

362

Nitrogen Concentration Estimation in Tomato Leaves by VIS-NIR Non-Destructive Spectroscopy  

PubMed Central

Nitrogen concentration in plants is normally determined by expensive and time consuming chemical analyses. As an alternative, chlorophyll meter readings and N-NO3 concentration determination in petiole sap were proposed, but these assays are not always satisfactory. Spectral reflectance values of tomato leaves obtained by visible-near infrared spectrophotometry are reported to be a powerful tool for the diagnosis of plant nutritional status. The aim of the study was to evaluate the possibility and the accuracy of the estimation of tomato leaf nitrogen concentration performed through a rapid, portable and non-destructive system, in comparison with chemical standard analyses, chlorophyll meter readings and N-NO3 concentration in petiole sap. Mean reflectance leaf values were compared to each reference chemical value by partial least squares chemometric multivariate methods. The correlation between predicted values from spectral reflectance analysis and the observed chemical values showed in the independent test highly significant correlation coefficient (r = 0.94). The utilization of the proposed system, increasing efficiency, allows better knowledge of nutritional status of tomato plants, with more detailed and sharp information and on wider areas. More detailed information both in space and time is an essential tool to increase and stabilize crop quality levels and to optimize the nutrient use efficiency. PMID:22163962

Ulissi, Valentina; Antonucci, Francesca; Benincasa, Paolo; Farneselli, Michela; Tosti, Giacomo; Guiducci, Marcello; Tei, Francesco; Costa, Corrado; Pallottino, Federico; Pari, Luigi; Menesatti, Paolo

2011-01-01

363

Life extension of structural components via an improved nondestructive testing methodology  

E-print Network

An experimental study was performed to determine the flaw detection sensitivity of advanced nondestructive testing (NDT) techniques with respect to structural applications. The techniques analyzed exemplify the incorporation ...

Hohmann, Brian P. (Brian Patrick)

2010-01-01

364

Exploratory loading techniques. [in holographic nondestructive testing of flat metal plates  

NASA Technical Reports Server (NTRS)

Interferometric holographic nondestructive testing of aluminum, copper, and steel flat plates is reported. Structural weaknesses under positive pressure, negative pressure, heating, and cooling are discussed.

Martin, A. M., III

1976-01-01

365

Passive solar: economics and ethics  

SciTech Connect

The economic feasibility of passive solar for space heating is examined. The key finding is that from the standpoint of society the costs of substitutes have been badly understated. The major source of error is valuing at average rather than replacement costs, using steady state furnace efficiencies, and failing to adjust for government subsidies in the production of fossil fuels. This provides a basis for explaining the failure of the market and individual choice. The issue of corrective policy is explained briefly from the standpoint of efficiency and ethical criteria.

Duffield, J.

1980-01-01

366

Passive longitudinal phase space linearizer  

NASA Astrophysics Data System (ADS)

We report on the possibility to passively linearize the bunch compression process in electron linacs for the next generation x-ray free electron lasers. This can be done by using the monopole wakefields in a dielectric-lined waveguide. The optimum longitudinal voltage loss over the length of the bunch is calculated in order to compensate both the second-order rf time curvature and the second-order momentum compaction terms. Thus, the longitudinal phase space after the compression process is linearized up to a fourth-order term introduced by the convolution between the bunch and the monopole wake function.

Craievich, P.

2010-03-01

367

Passive mitigation of mode instabilities  

NASA Astrophysics Data System (ADS)

The phenomenon of mode instabilities has quickly become the most limiting effect for a further scaling of the average power of fiber laser systems. Consequently it is of great importance to find solutions for this problem. In this work we propose two concrete possible passive mitigation strategies: the first one is based on the reduction of the heat load in the fiber, whereas the second one is based on the reduction of the pump absorption. In both cases a significant increase of the threshold is expected.

Jauregui, C.; Otto, H.-J.; Stutzki, F.; Jansen, F.; Limpert, J.; Tünnermann, A.

2014-03-01

368

Passive solar in China: traditional and new  

SciTech Connect

The authors' observations of a tradition of passive solar architecture in northern China are described. Tendencies for modern buildings to depart from this tradition are noted. Major passive solar research programs are discussed and experimental buildings are illustrated. It is concluded that the Chinese could realize a major advantage by combining their strong tradition of passive solar architecture with modern insulation methods and improved glazing systems.

Balcomb, J.D.; Balcomb, S.A.

1986-04-01

369

The Future of Passive Solar in Industry  

E-print Network

THE FUTURE OF PASSIVE SOLAR IN INDUSTRY Donald R. WUlfingh9ff, P.E. WUlfinghoff Energy Services, Inc. Wheaton, Maryland ABSTRACT Passive solar is a family of tech niques for the direct use of sunlight for illumination and heating.... Industrial facilities have characteristics which particularly favor the use of these tech niques. This paper examines the applic ability and economic potential of passive solar in the industrial environment, and offers specific suggestions for achieving...

Wulfinghoff, D. R.

370

Cellular automaton formulation of passive scalar dynamics  

NASA Technical Reports Server (NTRS)

Cellular automata modeling of the advection of a passive scalar in a two-dimensional flow is examined in the context of discrete lattice kinetic theory. It is shown that if the passive scalar is represented by tagging or 'coloring' automation particles a passive advection-diffusion equation emerges without use of perturbation expansions. For the specific case of the hydrodynamic lattice gas model of Frisch et al. (1986), the diffusion coefficient is calculated by perturbation.

Chen, Hudong; Matthaeus, William H.

1987-01-01

371

Dynamic, Nondestructive Imaging of a Bioengineered Vascular Graft Endothelium  

PubMed Central

Bioengineering of vascular grafts holds great potential to address the shortcomings associated with autologous and conventional synthetic vascular grafts used for small diameter grafting procedures. Lumen endothelialization of bioengineered vascular grafts is essential to provide an antithrombogenic graft surface to ensure long-term patency after implantation. Conventional methods used to assess endothelialization in vitro typically involve periodic harvesting of the graft for histological sectioning and staining of the lumen. Endpoint testing methods such as these are effective but do not provide real-time information of endothelial cells in their intact microenvironment, rather only a single time point measurement of endothelium development. Therefore, nondestructive methods are needed to provide dynamic information of graft endothelialization and endothelium maturation in vitro. To address this need, we have developed a nondestructive fiber optic based (FOB) imaging method that is capable of dynamic assessment of graft endothelialization without disturbing the graft housed in a bioreactor. In this study we demonstrate the capability of the FOB imaging method to quantify electrospun vascular graft endothelialization, EC detachment, and apoptosis in a nondestructive manner. The electrospun scaffold fiber diameter of the graft lumen was systematically varied and the FOB imaging system was used to noninvasively quantify the affect of topography on graft endothelialization over a 7-day period. Additionally, results demonstrated that the FOB imaging method had a greater imaging penetration depth than that of two-photon microscopy. This imaging method is a powerful tool to optimize vascular grafts and bioreactor conditions in vitro, and can be further adapted to monitor endothelium maturation and response to fluid flow bioreactor preconditioning. PMID:23585885

Lu, Peng; Xu, Yong; Rylander, Christopher G.; Wang, Ge; Sapoznik, Etai; Criswell, Tracy; Lee, Sang Jin; Soker, Shay; Rylander, Marissa Nichole

2013-01-01

372

Real-time nondestructive imaging with THz waves  

NASA Astrophysics Data System (ADS)

We present a real-time imaging measurement in the terahertz (THz) frequency region. The dynamic subtraction technique is used to reduce long-term optical background drift. The reflective images of two targets, a Nikon camera's lens cap and a plastic toy gun, are obtained. For the lens cap, the image data were processed to be false-color images. For the toy gun, we show that even under an optically opaque canvas bag, a clear terahertz image is obtained. It is shown that terahertz real-time imaging can be used to nondestructively detect concealed objects.

Zhang, LiangLiang; Karpowicz, Nick; Zhang, CunLin; Zhao, YueJin; Zhang, XiCheng

2008-03-01

373

Terahertz real-time imaging for nondestructive detection  

NASA Astrophysics Data System (ADS)

We present a real time imaging measurement in the terahertz (THz) frequency region. The dynamic subtraction technique is used to reduce long-term optical background drift. The reflective images of two targets, a Nikon camera's lens cap and a plastic toy gun, are obtained. For the lens cap, the image data were processed to be false color images. For the toy gun, we show that even under an optically opaque canvas bag, a clear terahertz image is obtained. It is shown that terahertz real time imaging can be used to nondestructively detect concealed objects.

Zhang, LiangLiang; Karpowicz, Nick; Zhang, CunLin; Zhao, YueJin; Zhang, XiCheng

2008-03-01

374

Non-destructive method for determining neutron exposure  

DOEpatents

A non-destructive method for determination of neutron exposure in an object, such as a reactor pressure vessel, is based on the observation of characteristic gamma-rays emitted by activation products in the object by using a unique continuous gamma-ray spectrometer. The spectrometer views the object through appropriate collimators to determine the absolute emission rate of these characteristic gamma-rays, thereby ascertaining the absolute activity of given activation products in the object. These data can then be used to deduce the spatial and angular dependence of neutron exposure at regions of interest within the object.

Gold, R.; McElroy, W.N.

1983-11-01

375

NON-DESTRUCTIVE ANALYSIS OF SHIELDED HIGHLY ENRICHED URANIUM  

SciTech Connect

Arms control and special nuclear material reduction requirements will eventually encompass shielded highly enriched uranium (HEU) systems. Non-destructive analysis (NDA) techniques for plutonium such as neutron multiplicity measurements and analysis are well developed and provide information regarding the properties of plutonium systems. In a previous study [1] we developed a NDA method for determining the mass and neutron multiplication of subcritical bare metal systems of HEU. In this work we present results for a HEU sphere enclosed within various shielding materials of low density, (carbon and beryllium), medium density (iron) and high density (lead).

C. L. HOLLAS; C. A. GOULDING; B. L. MEYERS

2001-04-01

376

Nondestructive Evaluation of Ceramic Matrix Composite Combustor Components  

NASA Technical Reports Server (NTRS)

Combustor liners fabricated from a SiC/SiC composite were nondestructively interrogated before and after combustion rig testing by X-ray, ultrasonic and thermographic techniques. In addition, mechanical test results were obtained from witness coupons, representing the as-manufactured liners, and from coupons machined from the components after combustion exposure. Thermography indications were found to correlate with reduced material properties obtained after rig testing. The thermography indications in the SiC/SiC liners were delaminations and damaged fiber tows, as determined through microstructural examinations. [copyright] 2003 American Institute of Physics

Sun, J. G.; Verrilli, M. J.; Stephan, R.; Barnett, T. R.; Ojard, G.

2003-01-01

377

Nondestructive evaluation of plasma-sprayed thermal barrier coatings  

SciTech Connect

Acoustic emission has been used as a nondestructive evaluation technique to examine the thermal shock response of thermal barrier coatings. In this study, samples of partially stabilized zirconia powder were sprayed and acoustic emission (AE) data were taken in a series of thermal shock tests in an effort to correlate AE with a given failure mechanism. Microstructural evidence was examined using parallel beam x-ray diffraction and optical microscopy. The AE data are discussed in terms of cumulative amplitude distributions and the use of this technique to characterize fracture events.

Andrews, D.J.; Taylor, J.A.T. [Alfred Univ., NY (United States). New York State Coll. of Ceramics

1997-10-01

378

Nondestructive inspection of Piper PA25 forward spar fittings  

SciTech Connect

The Federal Aviation Administration`s (FAA`s) Aging Aircraft NDI Validation Center (AANC) at Sandia National Laboratories applied two nondestructive inspection (NDI) techniques to inspect a forward spar fuselage attachment fitting. The techniques used were based on radiography and ultrasonic test methods. The combination of these techniques did reveal material thinning of two spar fittings from Piper PA25 aircraft. However, crack detection near a notch design feature could not be performed. Based on the results of these experiments, an ultrasonic test procedure was subsequently developed for the material thinning. The procedure has since been incorporated by the FAA into a revision of Airworthiness Directive 93-21-12.

Moore, D.G. [Sandia National Labs., Albuquerque, NM (United States)

1995-07-01

379

Nonlinear simulation of a nondestructive testing measurement system  

NASA Astrophysics Data System (ADS)

A nondestructive testing (NDT) equipment has been fabricated. The description of the measurement set-up with some measured crack signals applying a Hall-type sensor, furthermore, the T,?- ? potential formulation of the nonlinear eddy current field problem in the time domain can be found in this paper. The hysteresis characteristic of the material has been simulated by the previously developed neural network (NN) based isotropic vector hysteresis model. The nonlinear system of equations has been solved by the fixed-point iteration scheme via the polarization method. Comparisons between the results of the 3D simulations and the measurements are also presented.

Kuczmann, Miklós; Iványi, Amália

2006-02-01

380

Nondestructive Technique Survey for Assessing Integrity of Composite Firing Vessel  

SciTech Connect

The repeated use and limited lifetime of a composite tiring vessel compel a need to survey techniques for monitoring the structural integrity of the vessel in order to determine when it should be retired. Various nondestructive techniques were researched and evaluated based on their applicability to the vessel. The methods were visual inspection, liquid penetrant testing, magnetic particle testing, surface mounted strain gauges, thermal inspection, acoustic emission, ultrasonic testing, radiography, eddy current testing, and embedded fiber optic sensors. It was determined that embedded fiber optic sensor is the most promising technique due to their ability to be embedded within layers of composites and their immunity to electromagnetic interference.

Tran, A.

2000-08-01

381

Liberty Bell 7 Recovery Evaluation and Nondestructive Testing  

NASA Technical Reports Server (NTRS)

An inspection of the Mercury capsule, Liberty Bell 7, and its contents was made on September 1 and 2, 1999. The condition of the capsule and its contents was consistent with long-term exposure to salt water and high pressures at the bottom of the ocean. Many of the metallic materials suffered corrosion, whereas the polymer-based materials seem to have survived remarkably well. No identifiable items or structures were found that appeared to have any scientific value. At this time, no further nondestructive evaluation appears to be justified.

Madaras, Eric I.; Smith, William L.

1999-01-01

382

Laser heterodyne photothermal nondestructive method: extension to transparent probe  

NASA Astrophysics Data System (ADS)

We present a contribution to the development of the laser heterodyne method of nondestructive material analysis employing photothermal displacement (PTD) probe. PTD is a dominant factor of the photothermal effect in metals and semiconductors, where the derived linear dependence on absorbed energy exhibits a fingerprint of their physical properties. Theoretical consideration of the case of transparent probe is accomplished extending thermal diffusion model. Laser double heterodyne detection is verified for opaque and transparent probes, and in the exclusive case of silicon. The achieved resolution of photothermal displacement is less than 10 -12 m well above the limits of heterodyne measurement.

Pencheva, V.; Penchev, S.; Naboko, V.; Toyoda, K.; Donchev, T.

2007-03-01

383

Nondestructive analysis of Au-Cr layers in aged microcircuits  

SciTech Connect

Particle-induced x-ray emission (PIXE), Rutherford backscattering spectroscopy (RBS), and nuclear reaction analysis (NRA) are being used to investigated compositional changes in MK4 radar unit microelectronics resulting from possible age-related chromium diffusion in gold. Since the analysis is nondestructive, changes in the mechanical properties of the system can be more readily correlated to measured compositional changes at the buried interface. Measurements are conducted to investigate trace levels of chromium at the external Au surface, determine the actual gold layer thickness of the test sample, and measure compositional changes occurring at the Au-Cr interface.

Antolak, A.; Morse, D.; Wilson, K.

1997-11-01

384

Application of laser, holographic, nondestructive testing by impact loading.  

PubMed

A description of research on holographic, nondestructive testing (HNDT) with impact loading is presented to demonstrate the technique as a practical HNDT method. The advantages of impact, or impulse, loading coupled with pulsed-laser illumination for HNDT away from the laboratory are discussed. The effect of the loading position, exposure timing, and prestressing on test results is discussed in detail. Experimental verification of the appropriateness of pulsed-laser HNDT in the testing of honeycomb materials by using impact loading is discussed. PMID:21052176

Wang, J; Grant, I

1995-07-01

385

Efficient Nondestructive Evaluation of Prototype Carbon Fiber Reinforced Structures  

NASA Technical Reports Server (NTRS)

Thermography inspection is an optic based technology that can reduce the time and cost required to inspect propellant tanks or aero structures fabricated from composite materials. Usually areas identified as suspect in the thermography inspection are examined with ultrasonic methods to better define depth, orientation and the nature of the anomaly. This combination of nondestructive evaluation techniques results in a rapid and comprehensive inspection of composite structures. Examples of application of this inspection philosophy to prototype will be presented. Methods organizing the inspection and evaluating the results will be considered.

Russell, Samuel S.; Walker, James L.; Workman, Gary; Thom, Robert (Technical Monitor)

2002-01-01

386

Advances of unilateral mobile NMR in nondestructive materials testing.  

PubMed

Unilateral mobile NMR employs portable instrumentation with sensors, which are applied to the object from one side. Based on the principles of well-logging NMR, a hand-held sensor, the NMR-MOUSE (MObile Universal Surface Explorer) has been developed for nondestructive materials testing. In the following, a number of new applications of unilateral NMR in materials science are reviewed. They are the state assessment of polyethylene pipes, the characterization of wood, the in situ evaluation of stone conservation treatment, high-resolution profiling of rubber tubes and 2-D imaging for defect analysis in rubber products. PMID:15833612

Blümich, Bernhard; Casanova, Federico; Perlo, Juan; Anferova, Sophia; Anferov, Vladimir; Kremer, Kai; Goga, Nicolae; Kupferschläger, Klaus; Adams, Michael

2005-02-01

387

Effects of Isokinetic Passive Exercise and Isometric Muscle Contraction on Passive Stiffness  

PubMed Central

[Purpose] The purpose of this study was to investigate the effects of isokinetic passive exercise and motion velocity on passive stiffness. In addition, we also discuss the effects of the contraction of agonist and antagonist muscles on passive stiffness. [Subjects] The subjects were 20 healthy men with no bone or joint disease. [Methods] Isokinetic passive exercise and isometric muscle contraction were performed on an isokinetic dynamometer. The angular acceleration measured by the accelerometer was compared before and after each task. [Results] After the passive exercise, the angular acceleration increased in the phase of small damped oscillation. Moreover, the effect was higher at high-speed movement. The angular acceleration was decreased by the contraction of the agonist muscle. Conversely, the angular acceleration was increased by the contraction of the antagonist muscle. [Conclusion] Isokinetic passive exercise reduced passive stiffness. Our results suggest the possibility that passive stiffness is increased by agonist muscle contraction and decreased by antagonist muscle contraction. PMID:24259791

Terada, Shigeru; Miaki, Hiroichi; Uchiyama, Keita; Hayakawa, Shozo; Yamazaki, Toshiaki

2013-01-01

388

On-orbit Passive Thermography  

NASA Technical Reports Server (NTRS)

On July 12, 2006, British-born astronaut Piers Sellers became the first person to conduct thermal nondestructive evaluation experiments in space, demonstrating the feasibility of a new tool for detecting damage to the reinforced carbon-carbon (RCC) structures of the Shuttle. This new tool was an EVA (Extravehicular Activity, or spacewalk) compatible infrared camera developed by NASA engineers. Data was collected both on the wing leading edge of the Orbiter and on pre-damaged samples mounted in the Shuttle s cargo bay. A total of 10 infrared movies were collected during the EVA totaling over 250 megabytes of data. Images were downloaded from the orbiting Shuttle to Johnson Space Center for analysis and processing. Results are shown to be comparable to ground-based thermal inspections performed in the laboratory with the same type of camera and simulated solar heating. The EVA camera system detected flat-bottom holes as small as 2.54cm in diameter with 50% material loss from the back (hidden) surface in RCC during this first test of the EVA IR Camera. Data for the time history of the specimen temperature and the capability of the inspection system for imaging impact damage are presented.

Howell, Patricia A.; Winfree, William P.; Cramer, K. Elliott

2008-01-01

389

Passive propulsion in vortex wakes  

NASA Astrophysics Data System (ADS)

A dead fish is propelled upstream when its flexible body resonates with oncoming vortices formed in the wake of a bluff cylinder, despite being well outside the suction region of the cylinder. Within this passive propulsion mode, the body of the fish extracts sufficient energy from the oncoming vortices to develop thrust to overcome its own drag. In a similar turbulent wake and at roughly the same distance behind a bluff cylinder, a passively mounted high-aspect-ratio foil is also shown to propel itself upstream employing a similar flow energy extraction mechanism. In this case, mechanical energy is extracted from the flow at the same time that thrust is produced. These results prove experimentally that, under proper conditions, a body can follow at a distance or even catch up to another upstream body without expending any energy of its own. This observation is also significant in the development of low-drag energy harvesting devices, and in the energetics of fish dwelling in flowing water and swimming behind wake-forming obstacles.

Beal, D. N.; Hover, F. S.; Triantafyllou, M. S.; Liao, J. C.; Lauder, G. V.

390

Passive electroreception in aquatic mammals.  

PubMed

Passive electroreception is a sensory modality in many aquatic vertebrates, predominantly fishes. Using passive electroreception, the animal can detect and analyze electric fields in its environment. Most electric fields in the environment are of biogenic origin, often produced by prey items. These electric fields can be relatively strong and can be a highly valuable source of information for a predator, as underlined by the fact that electroreception has evolved multiple times independently. The only mammals that possess electroreception are the platypus (Ornithorhynchus anatinus) and the echidnas (Tachyglossidae) from the monotreme order, and, recently discovered, the Guiana dolphin (Sotalia guianensis) from the cetacean order. Here we review the morphology, function and origin of the electroreceptors in the two aquatic species, the platypus and the Guiana dolphin. The morphology shows certain similarities, also similar to ampullary electroreceptors in fishes, that provide cues for the search for electroreceptors in more vertebrate and invertebrate species. The function of these organs appears to be very similar. Both species search for prey animals in low-visibility conditions or while digging in the substrate, and sensory thresholds are within one order of magnitude. The electroreceptors in both species are innervated by the trigeminal nerve. The origin of the accessory structures, however, is completely different; electroreceptors in the platypus have developed from skin glands, in the Guiana dolphin, from the vibrissal system. PMID:23187861

Czech-Damal, Nicole U; Dehnhardt, Guido; Manger, Paul; Hanke, Wolf

2013-06-01

391

NCI Launches Proteomics Assay Portal  

Cancer.gov

In a paper recently published by the journal Nature Methods, Investigators from the National Cancer Institute’s Clinical Proteomic Tumor Analysis Consortium (NCI-CPTAC) announced the launch of a proteomics Assay Portal for multiple reaction monitoring-mass spectrometry (MRM-MS) assays. This community web-based repository for well-characterized quantitative proteomic assays currently consists of 456 unique peptide assays to 282 unique proteins and serves as a public resource of methodologies and data related to cancer associated targets.

392

Passive smoking, salivary cotinine concentrations, and middle ear effusion in 7 year old children  

Microsoft Academic Search

OBJECTIVE--To assess the contribution of passive exposure to tobacco smoke to the development of middle ear underpressure and effusion. DESIGN--Cross sectional observational study. SETTING--One third of the primary schools in Edinburgh. SUBJECTS--892 Children aged 6 1\\/2 to 7 1\\/2 were examined, and satisfactory tympanograms were obtained in 872. Results of assay of salivary cotinine concentrations were available for 770 children,

D. P. Strachan; M. J. Jarvis; C. Feyerabend

1989-01-01

393

Nondestructive Detection of Cracks in Ceramics Using Vicinal Illumination  

NASA Technical Reports Server (NTRS)

Cracks and other defects in ceramic materials can be difficult or impossible to examine and photograph due to the extreme lack of contrast. A method for inspecting translucent ceramics using scattered light, also known as vicinal illumination, will be described. This method has been known in the ceramics industry for quite some time, but is not well known in the testing and failure analysis community. Electronics applications include substrates, packages, multilayer capacitors, and thin film resistors. Ceramic materials are used in electronic applications as microcircuit packages and substrates which carry signals and power between microcircuits. Fine cracks in ceramic materials can result in mechanical failures, electrical failures, and loss of hermeticity. Often, fine cracks are difficult or impossible to detect using standard nondestructive inspection techniques such as visual inspection, ultrasonic inspection, or vapor crack detection. Dye penetrant inspection is usually effective, but contaminates the part, which is unacceptable for space flight hardware. One effective nondestructive inspection method of detecting cracks involves examining the way in which light scatters through the ceramic material when viewed with a standard bright field reflected light microscope. This method, termed vicinal illumination, has been used for detecting cracks during failure analyses of several part types, and screening of space flight hardware. The technique has proven effective on several different types of ceramic materials as well. A related method for use with dark field equipment has also been used to successfully locate otherwise invisible cracks.

Hull, Scott M.

1999-01-01

394

Nondestructive Degradation Evaluation of Ceramic Candle Filters Using Vibration Signatures  

SciTech Connect

The structural integrity of ceramic candle filters is a key element for hot gas cleanup systems, They protect the heat exchanger and gas turbine components from getting clogged and also prevent erosion. Ceramic candle filters used in the recent demonstration plant have experienced degradation and fracturing. Preliminary examination of these ceramic filters indicated that damage of the filters may have resulted from strength degradation at consistent high temperature operation, thermal transient events, excessive ash accumulation and bridging and pulse cleaning. The ceramic candle filter is a slender structure made of layers of porous materials. The structure has high acoustic attenuation which has greatly limited the conventional ultrasonic detection capability. In general, stiffness reduction of a structure will cause the change of the modal parameters of the structure. This study proposes a nondestructive approach for evaluating the structural properties of the ceramic filters using dynamic characterization method. The vibration signatures of the ceramic filters at different degradation levels are established using transient impact-response technique. Results from this study indicate that the vibration signatures of the filters can be used as an index to quantify the darnage condition of the filters. The results also indicate the feasibility of using the vibration mode shapes to predict the damage location. The application of this study can be implemented to develop a nondestructive evaluation method for future in-situ inspection of the ceramic filters.

Chen, R.H.L.; Parthasarathy, B. [Department of Civil and Environmental Engineering, West Virginia Univ., Morgantown, WV (United States)

1996-12-31

395

Nondestructive ultrasonic characterization of two-phase materials  

NASA Technical Reports Server (NTRS)

The development of ultrasonic methods for the nondestructive characterization of mechanical properties of two phase engineering materials are described. The primary goal was to establish relationships between the nonlinearity parameter and the percentage of solid solution phase in two phase systems such as heat treatable aluminum alloys. The acoustoelastic constant was also measured on these alloys. A major advantage of the nonlinearity parameter over that of the acoustoelastic constant is that it may be determined without the application of stress on the material, which makes the method more applicable to inservice nondestructive characterization. The results obtained on the heat treatable 7075 and the work hardenable 5086 and 5456 aluminum alloys show that both the acoustoelastic constant and the acoustic nonlinearity parameter change considerable with the volume fraction of second phase precipitates in these aluminum alloys. A mathematical model was also developed to relate the effective acoustic nonlinearity parameter to volume fraction of second phase precipitates in an alloy. The equation is approximated to within experimental error by a linear expression for volume fractions up to approx. 10%.

Salama, Kamel

1987-01-01

396

Eye tissue structure and refraction alterations upon nondestructive laser action  

NASA Astrophysics Data System (ADS)

A new approach to alterations in eye refraction upon nondestructive laser action on the sclera and cornea is studied. It is demonstrated in in vivo experiments on rabbit eyes that sequential laser irradiation of the sclera and cornea yields a significant alteration in the eye refraction. The collagen structure of the sclera and cornea is studied after the nondestructive laser action with noninvasive polarization-sensitive optical coherence tomography. It is demonstrated that collagen fibers that provide for the cornea tension and applanation partially survive in the zone of the local denaturation of sclera. An irradiation mode that corresponds to an increase in the cornea’s plasticity and does not cause visible structural changes is chosen. The simplest theoretical model for alterations in the eye refraction upon the nonablative laser action on sclera is analyzed. The alteration in the cornea curvature upon stretching resulting from the local sclera coagulation and the corresponding decrease in its volume is calculated. The model makes it possible to approximately estimate the laser irradiation modes that provide the desired alterations in eye refraction.

Sobol', E. N.; Baum, O. I.; Bol'Shunov, A. V.; Sipliviy, V. I.; Ignat'eva, N. Yu.; Zakharkina, O. L.; Lunin, V. V.; Omel'Chenko, A. I.; Kamenskiy, V. A.; Myakov, A. V.

2006-05-01

397

Large-diameter bacteriorhodopsin films for applications in nondestructive testing  

NASA Astrophysics Data System (ADS)

Bacteriorhodopsin (BR) films with dimension of 100 mm X 100 mm have been developed for applications in non- destructive testing. Films made from the photochromic retinal protein BR have been successfully employed in a variety of optical applications. Among them holographic interferometry for non-destructive testing which is one of the applications where the aperture of the BR-films used for recording plays an important role. The BR-films available earlier had an aperture of about 2/3 inch. Due to this limit size it was necessary to focus the light scattered from the object under investigation to the BR-film by means of lenses which in turn limit the optical resolution of the whole system. Now BR-films with a more than 50-fold larger are have been developed which allow lensless recording of the holograms. The optical quality of the films, in particular the spatial homogeneity of their optical density and their light sensitivity, is constant over the full aperture within a few percent. Applications of this new type of BR-films in non-destructive testing of ceramic parts are presented.

Hampp, Norbert A.; Seitz, Arne; Juchem, Thorsten; Oesterhelt, Dieter

1999-05-01

398

Holographic Nondestructive Testing: Review Of A Laser Inspection Tool  

NASA Astrophysics Data System (ADS)

A great deal has been written about holography, especially in the years since Gabor won the Nobel Prize (1971) for his "invention and development" of the method. While it is fairly safe to state that the movie and T.V. industries are not on the verge of a revolution as a result of the highly touted three-dimensional characteristics of the process, it can be said that holography may offer considerable scientific potential in such diverse areas as computer storage, display systems, correlation techniques, medical diagnostics (acoustical holography) and radar (microwave holography), to mention just a few. Another promising application of holography, and one that has been given considerable attention at United Technologies Corporation and other industrial laboratories, is nondestructive testing. Consideration shall be given to this subject in the present paper by starting with a very brief review of holography (The Basic Tool), followed by a description of interferometric hologra-phy (Preparing the Tool for Use), and how it can be employed to nondestructively identify defects (Applying the Tool). This sets the stage for two final topics which establish the holographic process as a viable NDT technique: pulsed holography (Adapting the Tool to the Industrial Environment) and special HNDT techniques (Simplifying and Diversifying Tool Application).

Erf, Robert K.

1982-10-01

399

Nondestructive estimation of anthocyanins and chlorophylls in anthocyanic leaves.  

PubMed

The anthocyanin and chlorophyll contents in leaves provide valuable information about the physiological status of plants. Thus, there is a need for accurate, efficient, and practical methodologies to estimate these biochemical parameters of vegetation. In this study, we tested the performance and accuracy of several nondestructive, reflectance-based techniques for estimating anthocyanin and chlorophyll contents in leaves of four unrelated species, European hazel (Corylus avellana), Siberian dogwood (Cornus alba =Swida alba), Norway maple (Acer platanoides), and Virginia creeper (Parthenocissus quinquefolia), with widely variable pigment content and composition. An anthocyanin reflectance index, which uses reflectances in the green and red edge spectral bands, and a modified anthocyanin reflectance index, employing, in addition, the near-infrared (NIR) band, were able to accurately estimate leaf anthocyanin for all species taken together with no reparameterization of algorithms. Total chlorophyll content was accurately estimated by a red edge chlorophyll index that uses spectral bands in the red edge and the NIR. These approaches can be used to estimate anthocyanin and chlorophyll nondestructively and allow the development of simple handheld field instrumentation. PMID:21622307

Gitelson, Anatoly A; Chivkunova, Olga B; Merzlyak, Mark N

2009-10-01

400

A demonstration of the gross count tomographic gamma scanner (GC-TGS) method for the nondestructive assay of transuranic waste  

SciTech Connect

The authors examined the accuracy and sensitivity levels for three variations on the TGS method: the original TGS method using a high-purity germanium (HPGe) detector to measure net areas of full-energy gamma-ray peaks; a modified HPGe-detector method that uses net areas for the transmission analysis and the gross count TGS (GC-TGS) method for the emission analysis; and a NaI-detector method that uses the GC-TGS method exclusively. They found that while the accuracies of the methods were comparable, the GC-TGS method boosted the sensitivity per detector by a factor of approximately two for the HPGe GC variation and four for the NaI method. The implications for improved TGS scanner design are discussed.

Estep, R.J.; Miko, D.; Melton, S.; Rawool-Sullivan, M.W.

1998-12-31

401

Determining Plutonium Mass in Spent Fuel with Nondestructive Assay Techniques NGSI Research Overview and Update on NDA Techniques  

E-print Network

NGSI active interrogation techniques, and a high-efficiencyLSDS is an active interrogation technique that has been usedtechniques, such factors as periodic structure of the fuel assembly, interrogation

A., V. Mozin, S.J. Tobin, L.W. Cambell, J.R. Cheatham, C.R. Freeman, C.J. Gesh,

2012-01-01

402

TGS[underscore]FIT: Image reconstruction software for quantitative, low-resolution tomographic assays  

SciTech Connect

We developed the computer program TGS[underscore]FIT to aid in researching the tomographic gamma scanner method of nondestructive assay. This software, written in C-programming, language, implements a full Beer's Law attenuation correction in reconstructing low-resolution emission tomograms. The attenuation coefficients for the corrections are obtained by reconstructing a transmission tomogram of the same resolution. The command-driven interface, combined with (crude) simulation capabilities and command file control, allows design studies to be performed in a semi-automated manner.

Estep, R J

1993-01-01

403

Automated Nondestructive Evaluation Method for Characterizing Ceramic and Metallic Hot Gas Filters  

SciTech Connect

The objective of this work was to develop a nondestructive (NDE), cost-effective and reliable method to assess the condition of rigid ceramic hot gas filters. The work was intended to provide an end user, as well as filter producers, with a nondestructive method to assess the ''quality'' or status of the filters.

Ellingson, W.A.; Pastila, P.; Koehl, E.R.; Wheeler, B.; Deemer, C.; Forster, G.A.

2002-09-19

404

Nondestructive Probing of Rabi Oscillations on the Cesium Clock Transition near the Standard Quantum Limit  

E-print Network

Nondestructive Probing of Rabi Oscillations on the Cesium Clock Transition near the Standard March 2008) We report on the nondestructive observation of Rabi oscillations on the Cs clock transition. Such Rabi oscillations are routinely ob- served in quantum dots [4], Josephson junction qubits [5], nitrogen

Saffman, Mark

405

Quantitative non-destructive evaluation of composite materials based on ultrasonic wave propagation  

NASA Technical Reports Server (NTRS)

The application and interpretation of specific ultrasonic nondestructive evaluation techniques are studied. The Kramers-Kronig or generalized dispersion relationships are applied to nondestructive techniques. Progress was made on an improved determination of material properties of composites inferred from elastic constant measurements.

Miller, J. G.

1986-01-01

406

Development of integrated passives QFN package  

Microsoft Academic Search

Integration of passives or discrete components is advantageous for end-customers in the simplification of their board design, board space-saving and overall cost reduction. The paper will discuss the development of integrating passives within a QFN package for an integrated power management solution. It is quickly found that placing together multiple components of varied dimensions and properties, pose challenges to manufacturability

Edwin Lim Jin Keong

2011-01-01

407

Cues for Understanding the Passive Voice.  

ERIC Educational Resources Information Center

Two experiments were conducted on the use and combination of three cues that differentiate active from passive verbs: a form of the auxiliary "be," the morphology of the passive participle of the verb, and the case-making preposition "by." In the first experiment, 59 children aged 2.9 to 5.10 years were asked to interpret sentences with one, two,…

Stromswold, Karin; And Others

1985-01-01

408

Strong local passivity in finite quantum systems.  

PubMed

Passive states of quantum systems are states from which no system energy can be extracted by any cyclic (unitary) process. Gibbs states of all temperatures are passive. Strong local (SL) passive states are defined to allow any general quantum operation, but the operation is required to be local, being applied only to a specific subsystem. Any mixture of eigenstates in a system-dependent neighborhood of a nondegenerate entangled ground state is found to be SL passive. In particular, Gibbs states are SL passive with respect to a subsystem only at or below a critical system-dependent temperature. SL passivity is associated in many-body systems with the presence of ground state entanglement in a way suggestive of collective quantum phenomena such as quantum phase transitions, superconductivity, and the quantum Hall effect. The presence of SL passivity is detailed for some simple spin systems where it is found that SL passivity is neither confined to systems of only a few particles nor limited to the near vicinity of the ground state. PMID:25122271

Frey, Michael; Funo, Ken; Hotta, Masahiro

2014-07-01

409

EVALUATION OF PASSIVE SAMPLING DEVICES (PSDS)  

EPA Science Inventory

The basic objectives of this study were to evaluate the performance of the EPA passive sampling device (PSD) for sampling of ambient level volatile organic compounds (VOC's); to develop an understanding of the mechanics of passive sampling using reversible adsorption; and to appl...

410

Passive electronic sensors in military operations  

Microsoft Academic Search

The use of passive electronic sensors in military operations and electronic warfare development are discussed. The advantages of electronic support measures regarding radar are pointed out, and passive and active electronic countermeasures such as jamming and deception are discussed; also considered are electronic counter-countermeasures such as antijamming, antianalysis and antideception. In addition, attention is given to ground-air operations in Vietnam,

R. Mastrofilippo

1980-01-01

411

Reclaiming the Passive-Aggressive Youth  

ERIC Educational Resources Information Center

Few children can control adult emotions more effectively than passive-aggressive youngsters. Their passive lack of compliance can incite even trained professionals to employ ineffective punitive responses. These responses confirm for the child the unreasonable and hurtful nature of adults. In this Life Space Crisis Intervention, the child makes a…

Marquoit, James W.

2004-01-01

412

Passive Identification and Analysis of TCP Anomalies  

E-print Network

and time, which is due to the closed-loop behavior of TCP, the TCP/IP client- server communication paradigmPassive Identification and Analysis of TCP Anomalies Marco Mellia, Michela Meo, Luca Muscariello on passive measurements of TCP traffic, main component of nowadays traffic. We propose a heuristic technique

413

Passive Solar Construction--Design and Performance.  

ERIC Educational Resources Information Center

Presented is a list of books and reports intended to serve as technical sources of information for the building professional interested in energy conservation. These publications are grouped under these headings: (1) energy-conserving building design; (2) passive systems/design; (3) passive systems/performance; and (4) proceedings (of the American…

Conservation and Renewable Energy Inquiry and Referral Service (DOE), Silver Spring, MD.

414

Passive Sampling of Atmospheric Photochemical Oxidants  

Microsoft Academic Search

A simple, cost-effective passive sampler is described that is suitable for measuring parts per billion (ppb) levels of photochemical oxidants (ozone + nitrogen dioxide + peroxyacetyl nitrate + peroxypropionyl nitrate) in ambient air. The passive sampler makes use of oxidant-fugitive colorants, and color changes are proportional to the oxidant dose, i.e. the product of oxidant concentration and sampling duration. Field

D. Grosjean; E. L. Williams Ii; E. Grosjean

1992-01-01

415

NDTCE'09, Non-Destructive Testing in Civil Engineering Nantes, France, June 30th July 3rd, 2009  

E-print Network

NDTCE'09, Non-Destructive Testing in Civil Engineering Nantes, France, June 30th ­ July 3rd, 2009 1 in Civil Engineering, France (2009)" #12;NDTCE'09, Non-Destructive Testing in Civil Engineering Nantes

Paris-Sud XI, Université de

416

Assays of ADAMTS-13 activity  

Microsoft Academic Search

Various assays for determination of ADAMTS-13 activity in plasma have been developed, all comprising two steps. The first step consists of proteolyzing a substrate by ADAMTS-13. Substrates were either exogenous von Willebrand factor (VWF) (purified from human plasma concentrates or recombinant VWF [rVWF]), purified VWF fragments, or endogenous VWF (from the tested plasma sample). All assays required a step in

Agnès Veyradier; Jean-Pierre Girma

2004-01-01

417

A Passive Magnetic Bearing Flywheel  

NASA Technical Reports Server (NTRS)

A 100 percent passive magnetic bearing flywheel rig employing no active control components was designed, constructed, and tested. The suspension clothe rotor was provided by two sets of radial permanent magnetic bearings operating in the repulsive mode. The axial support was provided by jewel bearings on both ends of the rotor. The rig was successfully operated to speeds of 5500 rpm, which is 65 percent above the first critical speed of 3336 rpm. Operation was not continued beyond this point because of the excessive noise generated by the air impeller and because of inadequate containment in case of failure. Radial and axial stiffnesses of the permanent magnetic bearings were experimentally measured and then compared to finite element results. The natural damping of the rotor was measured and a damping coefficient was calculated.

Siebert, Mark; Ebihara, Ben; Jansen, Ralph; Fusaro, Robert L.; Morales, Wilfredo; Kascak, Albert; Kenny, Andrew

2002-01-01

418

Passive Tracking System and Method  

NASA Technical Reports Server (NTRS)

System and methods are disclosed for passively determining the location of a moveable transmitter utilizing a pair of phase shifts at a receiver for extracting a direction vector from a receiver to the transmitter. In a preferred embodiment, a phase difference between the transmitter and receiver is extracted utilizing a noncoherent demodulator in the receiver. The receiver includes antenna array with three antenna elements, which preferably are patch antenna elements placed apart by one-half wavelength. Three receiver channels are preferably utilized for simultaneously processing the received signal from each of the three antenna elements. Multipath transmission paths for each of the three receiver channels are indexed so that comparisons of the same multipath component are made for each of the three receiver channels. The phase difference for each received signal is determined by comparing only the magnitudes of received and stored modulation signals to determine a winning modulation symbol.

Arndt, G. Dickey (Inventor); Ngo, Phong H. (Inventor); Chen, Henry A. (Inventor); Phan, Chau T. (Inventor); Bourgeois, Brian A. (Inventor); Dusl, John (Inventor); Hill, Brent W. (Inventor)

2005-01-01

419

Passive Tracking System and Method  

NASA Technical Reports Server (NTRS)

Systems and methods are disclosed for passively determining the location of a moveable transmitter utilizing a pair of phase shifts at a receiver for extracting a direction vector from a receiver to the transmitter. In a preferred embodiment, a phase difference between the transmitter and receiver is extracted utilizing a noncoherent demodulator in the receiver. The receiver includes an antenna array with three antenna elements, which preferably are patch antenna elements spaced apart by one-half wavelength. Three receiver channels are preferably utilized for simultaneously processing the received signal from each of the three antenna elements. Multipath transmission paths for each of the three receiver channels are indexed so that comparisons of the same multipath component are made for each of the three receiver channels. The phase difference for each received signal is determined by comparing only the magnitudes of received and stored modulation signals to determine a winning modulation symbol.

Arndt, G. Dickey (Inventor); Ngo, Phong H. (Inventor); Chen, Henry A. (Inventor); Phan, Chau T. (Inventor); Bourgeois, Brian A. (Inventor); Dusl, Jon (Inventor); Hill, Brent W. (Inventor)

2003-01-01

420

Passive Optical Sample Assembly (POSA)  

NASA Technical Reports Server (NTRS)

A Passive Optical Sample Assembly (POSA) unit was mounted and flown in the cargo bay of the space shuttle Columbia during the first Orbital Flight Test (OFT-1). A similar unit was mounted in a different location in the cargo bay during the postflight operations. The samples in both POSA arrays were subjected to a series of optical and analytical measurements prior to delivery for installation in the cargo bay and after retrieval of the flight hardware. The final results of a comparison of the two series of measurements are presented. These STS-1 results are based on data obtained from only a portion of one of the ten Induced Environment Contamination Monitor instruments to be flown on several shuttle flights beginning with STS-2. These limited results do not indicate shuttle contamination levels in excess of those anticipated.

Linton, R. C.; Miller, E. R.; Susko, M.

1981-01-01

421

Addressing Passive Smoking in Children  

PubMed Central

Background A significant number of parents are unaware or unconvinced of the health consequences of passive smoking (PS) in children. Physicians could increase parental awareness by giving personal advice. Aim To evaluate the current practices of three Dutch health professions (paediatricians, youth health care physicians, and family physicians) regarding parental counselling for passive smoking (PS) in children. Methods All physicians (n?=?720) representing the three health professions in Limburg, the Netherlands, received an invitation to complete a self-administered electronic questionnaire including questions on their: sex, work experience, personal smoking habits, counselling practices and education regarding PS in children. Results The response rate was 34%. One tenth (11%) of the responding physicians always addressed PS in children, 32% often, 54% occasionally and 4% reported to never attend to it. The three health professions appeared comparable regarding their frequency of parental counselling for PS in children. Addressing PS was more likely when children had respiratory problems. Lack of time was the most frequently mentioned barrier, being very and somewhat applicable for respectively 14% and 43% of the physicians. One fourth of the responders had received postgraduate education about PS. Additionally, 49% of the responders who did not have any education about PS were interested in receiving it. Conclusions Physicians working in the paediatric field in Limburg, the Netherlands, could more frequently address PS in children with parents. Lack of time appeared to be the most mentioned barrier and physicians were more likely to counsel parents for PS in children with respiratory complaints/diseases. Finally, a need for more education on parental counselling for PS was expressed. PMID:24809443

Hutchinson, Sasha G.; Kuijlaars, Jennifer S.; Mesters, Ilse; Muris, Jean W. M.; van Schayck, Constant P.; Dompeling, Edward; Feron, Frans J. M.

2014-01-01

422

Determine the Compressive Strength of Calcium Silicate Bricks by Combined Nondestructive Method  

PubMed Central

The paper deals with the application of combined nondestructive method for assessment of compressive strength of calcium silicate bricks. In this case, it is a combination of the rebound hammer method and ultrasonic pulse method. Calibration relationships for determining compressive strength of calcium silicate bricks obtained from nondestructive parameter testing for the combined method as well as for the L-type Schmidt rebound hammer and ultrasonic pulse method are quoted here. Calibration relationships are known for their close correlation and are applicable in practice. The highest correlation between parameters from nondestructive measurement and predicted compressive strength is obtained using the SonReb combined nondestructive method. Combined nondestructive SonReb method was proved applicable for determination of compressive strength of calcium silicate bricks at checking tests in a production plant and for evaluation of bricks built in existing masonry structures.

2014-01-01

423

PASSIVE MECHANICAL PROPERTIES AND RELATED PROTEINS CHANGE WITH BOTULINUM NEUROTOXIN A INJECTION OF NORMAL SKELETAL MUSCLE  

PubMed Central

Summary The effects of botulinum neurotoxin A on the passive mechanical properties of skeletal muscle have not been investigated, but may have significant impact in the treatment of neuromuscular disorders including spasticity. Single fiber and fiber bundle passive mechanical testing was performed on rat muscles treated with botulinum neurotoxin A. Myosin heavy chain and titin composition of single fibers was determined by gel electrophoresis. Muscle collagen content was determined using a hydroxyproline assay. Neurotoxin-treated single fiber passive elastic modulus was reduced compared to control fibers (53.00 kPa versus 63.43 kPa). Fiber stiffness and slack sarcomere length were also reduced compared to control fibers and myosin heavy chain composition shifted from faster to slower isoforms. Average titin molecular weight increased 1.77% after treatment. Fiber bundle passive elastic modulus increased following treatment (168.83 kPa versus 75.14 kPa). Bundle stiffness also increased while collagen content per mass of muscle tissue increased 38%. Injection of botulinum neurotoxin A produces an effect on the passive mechanical properties of normal muscle that is opposite to the changes observed in spastic muscles. PMID:21853457

Thacker, Bryan E.; Tomiya, Akihito; Hulst, Jonah B.; Suzuki, Kentaro P.; Bremner, Shannon N.; Gastwirt, Randy F.; Greaser, Marion L.; Lieber, Richard L.; Ward, Samuel R.

2011-01-01

424

Passive neutron design study for 200-L waste drums  

SciTech Connect

We have developed a passive neutron counter for the measurement of plutonium in 200-L drums of scrap and waste. The counter incorporates high efficiency for the multiplicity counting in addition to the traditional coincidence counting. The {sup 252}Cf add-a-source feature is used to provide an accurate assay over a wide range of waste matrix materials. The room background neutron rate is reduced by using 30 cm of external polyethylene shielding and the cosmic-ray background is reduced by statistical filtering techniques. Monte Carlo Code calculations were used to determine the optimum detector design, including the gas pressure, size, number, and placement of the {sup 3}He tubes in the moderator. Various moderators, including polyethylene, plastics, teflon, and graphite, were evaluated to obtain the maximum efficiency and minimum detectable mass of plutonium.

Menlove, H.O.; Beddingfield, D.B.; Pickrell, M.M. [and others

1997-09-01

425

A phaseguided passive batch microfluidic mixing chamber for isothermal amplification.  

PubMed

With a view to developing a rapid pathogen detection system utilizing isothermal nucleic acid amplification, the necessary micro-mixing step is innovatively implemented on a chip. Passive laminar flow mixing of two 6.5 ?l batches differing in viscosity is performed within a microfluidic chamber. This is achieved with a novel chip space-saving phaseguide design which allows, for the first time, the complete integration of a passive mixing structure into a target chamber. Sequential filling of batches prior to mixing is demonstrated. Simulation predicts a reduction of diffusive mixing time from hours down to one minute. A simple and low-cost fabrication method is used which combines dry film resist technology and direct wafer bonding. Finally, an isothermal nucleic acid detection assay is successfully implemented where fluorescence results are measured directly from the chip after a one minute mixing sequence. In combination with our previous work, this opens up the way towards a fully integrated pathogen detection system in a lab-on-a-chip format. PMID:22952055

Hakenberg, Sydney; Hügle, Matthias; Weidmann, Manfred; Hufert, Frank; Dame, Gregory; Urban, Gerald A

2012-11-01

426

From Antenna to Assay  

PubMed Central

Conspectus Ligand-sensitized, luminescent lanthanide(III) complexes are of considerable importance because their unique photophysical properties (microsecond to millisecond lifetimes, characteristic and narrow emission bands, and large Stokes shifts) make them well suited as labels in fluorescence-based bioassays. The long-lived emission of lanthanide(III) cations can be temporally resolved from scattered light and background fluorescence to vastly enhance measurement sensitivity. One challenge in this field is the design of sensitizing ligands that provide highly emissive complexes with sufficient stability and aqueous solubility for practical applications. In this Account, we give an overview of some of the general properties of the trivalent lanthanides and follow with a summary of advances made in our laboratory in the development of highly luminescent Tb(III) and Eu(III) complexes for applications in biotechnology. A focus of our research has been the optimization of these compounds as potential commercial agents for use in Homogeneous Time-Resolved Fluorescence (HTRF) technology. Our approach involves developing high-stability octadentate Tb(III) and Eu(III) complexes that rely on all-oxygen donor atoms and using multi-chromophore chelates to increase molar absorptivity; earlier examples utilized a single pendant chromophore (that is, a single “antenna”). Ligands based on 2-hydroxyisophthalamide (IAM) provide exceptionally emissive Tb(III) complexes with quantum yield values up to ?60% that are stable at the nanomolar concentrations required for commercial assays. Through synthetic modification of the IAM chromophore and time-dependent density functional theory (TD-DFT) calculations, we have developed a method to predict absorption and emission properties of these chromophores as a tool to guide ligand design. Additionally, we have investigated chiral IAM ligands that yield Tb(III) complexes possessing both high quantum yield values and strong circularly polarized luminescence (CPL) activity. To efficiently sensitize Eu(III) emission, we have used the 1-hydroxypyridin-2-one (1,2-HOPO) chelate to create remarkable ligands that combine excellent photophysical properties and exceptional aqueous stabilities. A more complete understanding of this chromophore has been achieved by combining low-temperature phosphorescence measurements with the same TD-DFT approach used with the IAM system. Eu(III) complexes with strong CPL activity have also been obtained with chiral 1,2-HOPO ligands. We have also undertaken the kinetic analysis of radiative and non-radiative decay pathways for a series of Eu(III) complexes; the importance of the metal ion symmetry on the ensuing photophysical properties is clear. Lastly, we describe a Tb(III)-IAM compound—now carried through to commercial availability—that offers improved performance in the common HTRF platform and has the potential to vastly improve sensitivity. PMID:19323456

Moore, Evan G.; Samuel, Amanda P. S.; Raymond, Kenneth N.

2009-01-01

427

Citric Acid Passivation of Stainless Steel  

NASA Technical Reports Server (NTRS)

Passivation is a process for cleaning and providing corrosion protection for stainless steel. Currently, on Kennedy Space Center (KSC), only parts passivated with nitric acid are acceptable for use. KSC disposes of approximately 125gal of concentrated nitric acid per year, and receives many parts from vendors who must also dispose of used nitric acid. Unfortunately, nitric acid presents health and environmental hazards. As a result, several recent industry studies have examined citric acid as an alternative. Implementing a citric acid-based passivation procedure would improve the health and environmental safety aspects of passivation process. However although there is a lack of published studies that conclusively prove citric acid is a technically sound passivation agent. In 2007, NASA's KSC Materials Advisory Working Group requested the evaluation of citric acid in place of nitric acid for passivation of parts at KSC. United Space Alliance Materials & Processes engineers have developed a three-phase test plan to evaluate citric acid as an alternative to nitric acid on three stainless steels commonly used at KSC: UNS S30400, S41000, and S17400. Phases 1 and 2 will produce an optimized citric acid treatment based on results from atmospheric exposure at NASA's Beach Corrosion Facility. Phase 3 will compare the optimized solution(s) with nitric acid treatments. If the results indicate that citric acid passivates as well or better than nitric acid, NASA intends to approve this method for parts used at the Kennedy Space Center.

Yasensky, David; Reali, John; Larson, Chris; Carl, Chad

2009-01-01

428

Non-destructive Faraday imaging of dynamically controlled ultracold atoms  

SciTech Connect

We describe an easily implementable method for non-destructive measurements of ultracold atomic clouds based on dark field imaging of spatially resolved Faraday rotation. The signal-to-noise ratio is analyzed theoretically and, in the absence of experimental imperfections, the sensitivity limit is found to be identical to other conventional dispersive imaging techniques. The dependence on laser detuning, atomic density, and temperature is characterized in a detailed comparison with theory. Due to low destructiveness, spatially resolved images of the same cloud can be acquired up to 2000 times. The technique is applied to avoid the effect of shot-to-shot fluctuations in atom number calibration, to demonstrate single-run vector magnetic field imaging and single-run spatial imaging of the system's dynamic behavior. This demonstrates that the method is a useful tool for the characterization of static and dynamically changing properties of ultracold atomic clouds.

Gajdacz, Miroslav; Pedersen, Poul L.; Mørch, Troels; Hilliard, Andrew J.; Arlt, Jan; Sherson, Jacob F. [Danish National Research Foundation Center for Quantum Optics, Institut for Fysik og Astronomi, Aarhus Universitet, Ny Munkegade 120, 8000 Aarhus C (Denmark)] [Danish National Research Foundation Center for Quantum Optics, Institut for Fysik og Astronomi, Aarhus Universitet, Ny Munkegade 120, 8000 Aarhus C (Denmark)

2013-08-15

429

Nerva fuel nondestructive evaluation and characterization equipment and facilities  

NASA Astrophysics Data System (ADS)

Nuclear Thermal Propulsion (NTP) is one of the technologies that the Space Exploration Initiative (SEI) has identified as essential for a manned mission to Mars. A base or prior work is available upon which to build in the development of nuclear rockets. From 1955 to 1973, the U.S Atomic Energy Commission (AEC) sponsored development and testing of a nuclear rocket engine under Project Rover. The rocket engine, called the Nuclear Engine for Rocket Vehicle Application (NERVA), used a graphite fuel element incorporating coated particle fuel. Much of the NERVA development and manufacturing work was performed at the Oak Ridge Y-12 Plant. This paper gives a general review of that work in the area of nondestructive evaluation and characterization. Emphasis is placed on two key characteristics: uranium content and distribution and thickness profile of metal carbide coatings deposited in the gas passage holes.

Caputo, Anthony J.

1993-01-01

430

High speed, nondestructive readout from thin-film ferroelectric memory  

NASA Technical Reports Server (NTRS)

High-speed polarization-direction-dependent photoresponse from ferroelectric lead zirconate titanate (PbZr(0.53)Ti(0.47)O3) thin films sandwiched between conducting electrodes to form a memory capacitor is reported. Laser pulses with a full width at half maximum of around 10 ns at 532-nm wavelength are utilized to readout the photoresponse signal from individual polarized elements. Such readout is repeated over a million times, with no detectable degradation in the photoresponse or the remanent polarization suggesting its potential as a nondestructive readout (NDRO) of nonvolatile polarization state in thin-film ferroelectric memories. In principle both electronic as well as thermal mechanisms could be triggered by such photon exposure of ferroelectric thin films. A comparison of the photoresponse from capacitors with semitransparent and opaque top electrodes suggests that the observed NDRO signal is primarily due to thermally triggered mechanisms.

Thakoor, Sarita

1992-01-01

431

Nondestructive millimeter wave imaging and spectroscopy using dielectric focusing probes  

NASA Astrophysics Data System (ADS)

A tool for interrogating objects over a wide band of frequencies with subwavelength resolution at small standoff distances (near field region) in the transmission mode using a single source and detector measurement setup in the millimeter wave band is presented. The design utilizes optics like principles for guiding electromagnetic millimeter waves from large cross-sectional areas to considerably smaller sub-wavelength areas. While plano-convex lenses can be used to focus waves to a fine resolution, they usually require a large stand-off distance thus resulting in alignment and spacing issues. The design procedure and simulation analysis of the focusing probes are presented in this study along with experimental verification of performance and imaging and spectroscopy examples. Nondestructive evaluation will find benefit from such an apparatus including biological tissue imaging, electronic package integrity testing, composite dielectric structure evaluation for defects and microfluidic sensing.

Hejase, Jose A.; Shane, Steven S.; Park, Kyoung Y.; Chahal, Premjeet

2014-02-01

432

Nondestructive characterization methods for monolithic solid oxide fuel cells  

SciTech Connect

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.

Ellingson, W.A.

1993-01-01

433

Nondestructive testing and flow visualization: Two aerospace applications of holography  

NASA Technical Reports Server (NTRS)

The application of holography to both nondestructive testing (NDT) and flow visualization is discussed. In the NDT area, particular attention is given to determining the most suitable stress systems for recognizing potential defects within aerospace materials and components when subjected to interferometric holographic examination. It was found that pressure cycling is most appropriate for studying honeycomb structures, diffusion bonds, electron beam and resistance welds, rubber laminates, and solid-propellant-to-liner disbonds; acoustic excitation procedures are preferred for composite bond studies, material thickness measurement, and vibration analysis; and thermal shocking shows promise for the inspection of some composite components. Representative results from these investigations are summarized with the intent of describing the several tools which were developed and are now available for studying the various problems confronting the aerospace industry.

Erf, R. K.; Gagosz, R. M.; Waters, J. P.

1973-01-01

434

Combining multiple nondestructive inspection images with a generalized additive model  

NASA Astrophysics Data System (ADS)

In this paper, multiple nondestructive inspection (NDI) images are combined with a generalized additive model to achieve a more precise and reliable assessment of hidden corrosion in aircraft lap joints. Two inspection techniques are considered in this study. One is the conventional multi-frequency eddy current testing technique and the other is the pulsed eddy current technique. To characterize the thickness loss or equivalently to achieve a quantitative measure of corrosion, multiple NDI images are fused to produce a thickness map that reflected the amount of corrosion damage. These results are further compared with corresponding digital x-ray thickness maps, which are obtained by mapping the remaining thickness after the specimen is dissembled and all the corrosion products are cleaned. Experimental results demonstrate that the proposed algorithms outperform the traditional calibration method aligned with a single testing approach.

Liu, Zheng; Ramuhalli, Pradeep; Safizadeh, Saeed; Forsyth, David S.

2008-08-01

435

Remote monitoring and nondestructive evaluation of wind turbine towers  

NASA Astrophysics Data System (ADS)

Wind turbine towers are in need of condition monitoring so as to lower the cost of unexpected maintenance. Wind loading from turbulence and gusts can cause damage in horizontal axis wind turbines even the supporting towers. Monitoring of wind turbines in service using embedded data sensor arrays usually is not targeted at the turbine-tower interaction from the perspective of structural dynamics. In this study the remote monitoring of the tower supporting a horizontal-axis wind turbine was attempted using a microwave interferometer. The dominant frequency of one tower was found to be decreased by more than 20% in 16 months. Numerical modeling using spectral finite elements is in progress and should provide further information regarding frequency shift due to stiffness variation and added mass. Expected outcome will contribute to remote monitoring procedures and nondestructive evaluation techniques for local wind turbine structures during operation.

Chiang, Chih-Hung; Yu, Chih-Peng; Hsu, Keng-Tsang; Cheng, Chia-Chi; Ke, Ying-Tzu; Shih, Yi-Ru

2014-03-01

436

Microwave Nondestructive Evaluation of Dielectric Materials with a Metamaterial Lens  

NASA Technical Reports Server (NTRS)

A novel microwave Nondestructive Evaluation (NDE) sensor was developed in an attempt to increase the sensitivity of the microwave NDE method for detection of defects small relative to a wavelength. The sensor was designed on the basis of a negative index material (NIM) lens. Characterization of the lens was performed to determine its resonant frequency, index of refraction, focus spot size, and optimal focusing length (for proper sample location). A sub-wavelength spot size (3 dB) of 0.48 lambda was obtained. The proof of concept for the sensor was achieved when a fiberglass sample with a 3 mm diameter through hole (perpendicular to the propagation direction of the wave) was tested. The hole was successfully detected with an 8.2 cm wavelength electromagnetic wave. This method is able to detect a defect that is 0.037 lambda. This method has certain advantages over other far field and near field microwave NDE methods currently in use.

Shreiber, Daniel; Gupta, Mool; Cravey, Robin L.

2008-01-01

437

Non-destructively shattered mesoporous silica for protein drug delivery  

PubMed Central

Mesoporous silicas have been extensively used for entrapping small chemical molecules and biomacromolecules for drug delivery. We hypothesize that the loading density of biomacromlecules such as proteins in mesoporous silicas could be limited due to disordering in the pore structure and long diffusion time in the pore channels. We shattered mesoporous silicas non-destructively resulting in improved intramesoporous structures and reduced particle sizes in aqueous solutions by a powerful sonication, where the mesoporous structures were still well maintained. The sonication-shattered mesoporous silica can increase the protein loading density to nearly 2.7 times as high as that of the non-shattered one, demonstrating that significantly more mesopore space of the silica could be accessible by the protein molecules, which may result in more sustained protein drug delivery. PMID:23687455

Lei, Chenghong; Chen, Baowei; Li, Xiaolin; Qi, Wen; Liu, Jun

2013-01-01

438

Nondestructive monitoring damage in composites using scanning laser acoustic microscopy  

NASA Technical Reports Server (NTRS)

Several Nicalon fiber reinforced LAS (lithium alumino-silicate) glass matrix composites were tested to study the relation between the residual strength and the different amounts of damage. The samples were fatigued by four-point cyclic loading at a 5 Hz rate at 500 C for a different number of cycles. 10 MHz scanning laser acoustic microscope (SLAM) images were taken to monitor damage on the samples. Our SLAM results indicate that there were defects already existing throughout the sample before fatigue, and the resultant damage pattern from fatigue could be related to the initial defect distribution in the sample. Finally, the fatigued samples were fractured and the residual strength data could not be explained by the cyclic fatigue alone. Rather, the damage patterns evident in the SLAM images were needed to explain the scatter in the data. The results show that SLAM is useful in nondestructively monitoring damage and estimating residual strength of fatigued ceramic composites.

Wey, A. C.; Kessler, L. W.; Dos Reis, H. L. M.

1992-01-01

439

Passive smoking elevates neurotrophin levels in tears.  

PubMed

The effect of passive smoking on levels of neurotrophin in tears was studied in normal subjects or patients with atopic keratoconjunctivitis (AKC). Basal levels of neurotrophins, nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT-3) and NT-4, in tears were significantly higher in AKC patients than those in normal subjects. Passive smoking had no effect on levels of neurotrophin in tears of normal subjects, while it elevated levels of NGF, BDNF, NT-3 and NT-4 in tears of AKC patients. These results indicate that passive smoking elevates levels of neurotrophin in tears, which in turn may aggravate AKC. PMID:15222398

Kimata, Hajime

2004-05-01

440

Passive Cooling of Body Armor  

NASA Astrophysics Data System (ADS)

Warfighter performance can be adversely affected by heat load and weight of equipment. Current tactical vest designs are good insulators and lack ventilation, thus do not provide effective management of metabolic heat generated. NRL has undertaken a systematic study of tactical vest thermal management, leading to physics-based strategies that provide improved cooling without undesirable consequences such as added weight, added electrical power requirements, or compromised protection. The approach is based on evaporative cooling of sweat produced by the wearer of the vest, in an air flow provided by ambient wind or ambulatory motion of the wearer. Using an approach including thermodynamic analysis, computational fluid dynamics modeling, air flow measurements of model ventilated vest architectures, and studies of the influence of fabric aerodynamic drag characteristics, materials and geometry were identified that optimize passive cooling of tactical vests. Specific architectural features of the vest design allow for optimal ventilation patterns, and selection of fabrics for vest construction optimize evaporation rates while reducing air flow resistance. Cooling rates consistent with the theoretical and modeling predictions were verified experimentally for 3D mockups.

Holtz, Ronald; Matic, Peter; Mott, David

2013-03-01

441

Passive fault current limiting device  

DOEpatents

A passive current limiting device and isolator is particularly adapted for use at high power levels for limiting excessive currents in a circuit in a fault condition such as an electrical short. The current limiting device comprises a magnetic core wound with two magnetically opposed, parallel connected coils of copper, a high temperature superconductor or other electrically conducting material, and a fault element connected in series with one of the coils. Under normal operating conditions, the magnetic flux density produced by the two coils cancel each other. Under a fault condition, the fault element is triggered to cause an imbalance in the magnetic flux density between the two coils which results in an increase in the impedance in the coils. While the fault element may be a separate current limiter, switch, fuse, bimetal strip or the like, it preferably is a superconductor current limiter conducting one-half of the current load compared to the same limiter wired to carry the total current of the circuit. The major voltage during a fault condition is in the coils wound on the common core in a preferred embodiment. 6 figs.

Evans, D.J.; Cha, Y.S.

1999-04-06

442

Passive fault current limiting device  

DOEpatents

A passive current limiting device and isolator is particularly adapted for use at high power levels for limiting excessive currents in a circuit in a fault condition such as an electrical short. The current limiting device comprises a magnetic core wound with two magnetically opposed, parallel connected coils of copper, a high temperature superconductor or other electrically conducting material, and a fault element connected in series with one of the coils. Under normal operating conditions, the magnetic flux density produced by the two coils cancel each other. Under a fault condition, the fault element is triggered to cause an imbalance in the magnetic flux density between the two coils which results in an increase in the impedance in the coils. While the fault element may be a separate current limiter, switch, fuse, bimetal strip or the like, it preferably is a superconductor current limiter conducting one-half of the current load compared to the same limiter wired to carry the total current of the circuit. The major voltage during a fault condition is in the coils wound on the common core in a preferred embodiment.

Evans, Daniel J. (Wheeling, IL); Cha, Yung S. (Darien, IL)

1999-01-01

443

PASSIVE DETECTION OF VEHICLE LOADING  

SciTech Connect

The Digital Imaging and Remote Sensing Laboratory (DIRS) at the Rochester Institute of Technology, along with the Savannah River National Laboratory is investigating passive methods to quantify vehicle loading. The research described in this paper investigates multiple vehicle indicators including brake temperature, tire temperature, engine temperature, acceleration and deceleration rates, engine acoustics, suspension response, tire deformation and vibrational response. Our investigation into these variables includes building and implementing a sensing system for data collection as well as multiple full-scale vehicle tests. The sensing system includes; infrared video cameras, triaxial accelerometers, microphones, video cameras and thermocouples. The full scale testing includes both a medium size dump truck and a tractor-trailer truck on closed courses with loads spanning the full range of the vehicle's capacity. Statistical analysis of the collected data is used to determine the effectiveness of each of the indicators for characterizing the weight of a vehicle. The final sensing system will monitor multiple load indicators and combine the results to achieve a more accurate measurement than any of the indicators could provide alone.

Garrett, A.

2012-01-03

444

Passive environmental temperature control system  

DOEpatents

Passive environmental heating and cooling systems are described, which utilize heat pipes to transmit heat to or from a thermal reservoir. In a solar heating system, a heat pipe is utilized to carry heat from a solar heat absorber plate that receives sunlight, through a thermal insulation barrier, to a heat storage wall, with the outer end of the pipe which is in contact with the solar absorber being lower than the inner end. The inclining of the heat pipe assures that the portion of working fluid, such as Freon, which is in a liquid phase will fall by gravity to the outer end of the pipe, thereby assuring diode action that prevents the reverse transfer of heat from the reservoir to the outside on cool nights. In a cooling system, the outer end of the pipe which connects to a heat dissipator, is higher than the inner end that is coupled to a cold reservoir, to allow heat transfer only out of the reservoir to the heat dissipator, and not in the reverse direction.

Corliss, John M. (Columbus, OH); Stickford, George H. (Columbus, OH)

1981-01-01

445

Rapid nonchromatographic assay for aminopropyltransferases  

SciTech Connect

Aminopropyltransferases are key enzymes in the biosynthesis of the polyamines spermidine and spermine. A procedure is described for assaying these enzymes be differential charcoal adsorption of /sup 14/C-labeled decarboxylated adenosylmethionine substrate from the labeled polyamine product. This assay is linear with time and enzyme concentration, and is suitable for use with a variety of amine acceptors. This procedure has the advantage, over those previously used, that it is extremely rapid yet very sensitive.

Anton, D.L.

1986-01-01

446

Passive and active thermography for in situ damage monitoring in woven composites during mechanical testing  

NASA Astrophysics Data System (ADS)

The aim of the present paper is to highlight the contribution of both passive and active infrared thermography for in situ damage detection and monitoring in a 2D woven composite, during a mechanical testing constituted of multiple sequences of loadings and intermediate pauses. During the monotonic tensile loadings, damages such as matrix cracking and fiber-matrix debondings are monitored by passive thermography. Their thermal signatures are analyzed and the released heat, which is assumed to be a relevant index of their severity, is evaluated and correlated to the associated acoustic energies, simultaneously recorded. Finally, the contribution of the TSR (Thermographic Signal Reconstruction) advanced processing technique to provide a qualitative overview of the detected damages is underlined. As for the constant stress plateau levels, a nondestructive damage inspection of the tested specimen is carried out by pulsed thermography. The difficulties, due to the woven structure of the composite, in detecting any damage are put into relief. Once more, it is shown that the TSR technique can be useful.

Roche, J.-M.; Balageas, D.; Lamboul, B.; Bai, G.; Passilly, F.; Mavel, A.; Grail, G.

2013-01-01

447

Passive machine augmented composite for multifunctional properties  

E-print Network

This dissertation studies by experiment and numerical analysis an advanced composite material (Machine Augmented Composite or MAC) for enhancement of the passive damping while maintaining its stiffness. This MAC is composed of a pre-buckled wall...

Kim, Jong Hyun

2005-11-01

448

Comparison of active and passive FTIR  

NASA Astrophysics Data System (ADS)

This paper discusses the result of a field trial in which active and passive FTIRs measured plume concentration pathlength (CL). It will be shown that when the coadding duration of passive systems was the same as active systems, nearly identical CL values were obtained. At the field trial, plumes of SF6 were released. The release rate and duration were controlled using a flowmeter. All the FTIR systems were monitoring approximately the same spot in the plume. Weather station data and flowmeter data were used with a gaussian plume model to predict downwind CLs. The active CLs were determined with standard CLS processing. The passive CLs were determined by converting the passive spectra to radiometric spectra. From the radiometric spectra, the air temperature and background temperature were derived. With this information, the absorbance was calculated and the CL was determined from the absorbance peak of the chemical.

Gruber, Thomas C., Jr.; Grim, Larry B.; Ditillo, John T.

1998-08-01

449

Passive and active solar heating technology  

SciTech Connect

This source of information about solar heating technology examines both passive heating approaches, such as direct gain, Trombe wall, and sunspace systems, and active designs for heating buildings, water supplies, and swimming pools.

Meltzer, M.

1985-01-01

450

The Soil Moisture Active Passive (SMAP) Mission  

E-print Network

The Soil Moisture Active Passive (SMAP) mission is one of the first Earth observation satellites being developed by NASA in response to the National Research Council's Decadal Survey. SMAP will make global measurements of ...

Entekhabi, Dara

451

Market ecology of active and passive investors  

NASA Astrophysics Data System (ADS)

We study the role of active and passive investors in an investment market with uncertainties. Active investors concentrate on a single or a few stocks with a given probability of determining the quality of them. Passive investors spread their investment uniformly, resembling buying the market index. In this toy market stocks are introduced as good and bad. If a stock receives sufficient investment it will survive, otherwise die. Active players exert a selective pressure since they can determine to an extent the investment quality. We show that the active players provide the driving force, whereas the passive ones act as free riders. While their gains do not differ too much, we show that the active players enjoy an edge. Their presence also provides better gains to the passive players and stocks themselves.

Capocci, Andrea; Zhang, Yi-Cheng

2001-09-01

452

Passive Earth Entry Vehicle Energy Absorbing Systems  

NASA Astrophysics Data System (ADS)

A critical element of a passive EEV performance is the energy absorbing system required to attenuate the dynamic landing loads. Two design approaches are described and the pros and cons based on particular mission requirements are discussed.

Kellas, S.; Maddock, R. W.

2014-06-01

453

Interior planning of passive solar housing  

SciTech Connect

A study involving 28 Virginia passive solar homeowners was conducted in 1984 to examine their reactions to passive design. The results indicate that a significant source of dissatisfaction was in space planning; the majority of the homeowners had difficulty arranging furniture in the living room. The spatial analysis of the floor plans revealed that the configuration of the open plan and circulation as well as passive design features contributed to these space planning problems. Design guidelines and recommendations that incorporate the research findings are also presented. In terms of other considerations, these homeowners were very satisfied with their passive solar homes. This satisfaction seemed to be related to psychological factors; sunlight, spaciousness, and openness were frequently cited as the most pleasing elements of the designs.

McLain-Kark, J.

1987-01-01

454

Integration of TGS and CTEN assays using the CTEN{_}FIT analysis and databasing program  

SciTech Connect

The CTEN{_}FIT program, written for Windows 9x/NT in C++, performs databasing and analysis of combined thermal/epithermal neutron (CTEN) passive and active neutron assay data and integrates that with isotopics results and gamma-ray data from methods such as tomographic gamma scanning (TGS). The binary database is reflected in a companion Excel database that allows extensive customization via Visual Basic for Applications macros. Automated analysis options make the analysis of the data transparent to the assay system operator. Various record browsers and information displays simplified record keeping tasks.

Estep, R. [and others

2000-05-01

455

Methods of Reducing Bias in Combined Thermal/Epithermal Neutron (CTEN) Assays of Heterogeneous Waste  

SciTech Connect

We examined the effectiveness of two different methods for correcting CTEN passive and active assays for bias due to variations in the source position in different drum types. Both use the same drum-averaged correction determined from a neural network trained to active flux monitor ratios as a starting point. One method then uses a neural network to obtain a spatial correction factor sensitive to the source location. The other method uses emission tomography. Both methods were found to give significantly improved assay accuracy over the drum-averaged correction, although more study is needed to determine which method works better.

Estep, R.J.; Melton, S.; Miko, D.

1998-11-17

456

Immune Response to Cryptococcus neoformans Soluble Polysaccharide I. Serological Assay for Antigen and Antibody  

PubMed Central

Chromium chloride was used as a coupling agent for the conjugation of purified cryptococcal polysaccharide to sheep erythrocytes. Sensitized erythrocytes were used in a passive hemagglutination (PHA) assay for antibody to cryptococcal polysaccharide and a passive hemagglutination inhibition (PHI) assay for antigen. The PHA assay was more sensitive than complement fixation, agglutination, or precipitation tests for antibody. The PHI assay could detect submicrogram quantities of soluble polysaccharide. Antigen or antibody could be detected in serum or spinal fluid from seven of eight patients with cryptococcosis. Tests for antigen or antibody were negative with sera from patients with histoplasmosis, blastomycosis, coccidioidomycosis, aspergillosis, or allescheriosis. A low frequency (3%) of positive reactors for antibody was found among sera from normal persons and from persons with unrelated diseases; whereas, all tests for antigen were negative. The assay showed a high degree of sensitivity for immunoglobulins of the immunoglobulin M class; however, cryptococcal antibody of the immunoglobulin G class was also detected. The immunological specificity of the polysaccharide preparation was due to carbohydrate rather than to protein associated with the polysaccharide. PMID:4570986

Kozel, Thomas R.; Cazin, John

1972-01-01

457

Site Map | Clinical Assay Development Program (CADP)  

Cancer.gov

Skip to Content Search this site Site Map Home About CADP Mission Background CADP Resources for Assay Development CADN — Clinical Assay Development Network CADC — Clinical Assay Development Center SRS — Specimen Retrieval System Access to CADP Resources Eligibility Instructions Submit

458

Galaxy Zoo: passive red spirals  

NASA Astrophysics Data System (ADS)

We study the spectroscopic properties and environments of red (or passive) spiral galaxies found by the Galaxy Zoo project. By carefully selecting face-on disc-dominated spirals, we construct a sample of truly passive discs (i.e. they are not dust reddened spirals, nor are they dominated by old stellar populations in a bulge). As such, our red spirals represent an interesting set of possible transition objects between normal blue spiral galaxies and red early types, making up ~6 per cent of late-type spirals. We use optical images and spectra from Sloan Digital Sky Survey to investigate the physical processes which could have turned these objects red without disturbing their morphology. We find red spirals preferentially in intermediate density regimes. However, there are no obvious correlations between red spiral properties and environment suggesting that environment alone is not sufficient to determine whether a galaxy will become a red spiral. Red spirals are a very small fraction of all spirals at low masses (M* < 1010 Msolar), but are a significant fraction of the spiral population at large stellar masses showing that massive galaxies are red independent of morphology. We confirm that as expected, red spirals have older stellar populations and less recent star formation than the main spiral population. While the presence of spiral arms suggests that a major star formation could not have ceased a long ago (not more than a few Gyr), we show that these are also not recent post-starburst objects (having had no significant star formation in the last Gyr), so star formation must have ceased gradually. Intriguingly, red spirals are roughly four times as likely than the normal spiral population to host optically identified Seyfert/low-ionization nuclear emission region (LINER; at a given stellar mass and even accounting for low-luminosity lines hidden by star formation), with most of the difference coming from the objects with LINER-like emission. We also find a curiously large optical bar fraction in the red spirals (70 +/- 5 verses 27 +/- 5 per cent in blue spirals) suggesting that the cessation of star formation and bar instabilities in spirals are strongly correlated. We conclude by discussing the possible origins of these red spirals. We suggest that they may represent the very oldest spiral galaxies which have already used up their reserves of gas - probably aided by strangulation or starvation, and perhaps also by the effect of bar instabilities moving material around in the disc. We provide an online table listing our full sample of red spirals along with the normal/blue spirals used for comparison. This publication has been made possible by the participation of more than 160000 volunteers in the Galaxy Zoo project. Their contributions are individually acknowledged at http://www.galaxyzoo.org/Volunteers.aspx E-mail: karen.masters@port.ac.uk

Masters, Karen L.; Mosleh, Moein; Romer, A. Kathy; Nichol, Robert C.; Bamford, Steven P.; Schawinski, Kevin; Lintott, Chris J.; Andreescu, Dan; Campbell, Heather C.; Crowcroft, Ben; Doyle, Isabelle; Edmondson, Edward M.; Murray, Phil; Raddick, M. Jordan; Slosar, Anže; Szalay, Alexander S.; Vandenberg, Jan

2010-06-01

459

Expansion-based passive ranging  

NASA Technical Reports Server (NTRS)

This paper describes a new technique of passive ranging which is based on utilizing the image-plane expansion experienced by every object as its distance from the sensor decreases. This technique belongs in the feature/object-based family. The motion and shape of a small window, assumed to be fully contained inside the boundaries of some object, is approximated by an affine transformation. The parameters of the transformation matrix are derived by initially comparing successive images, and progressively increasing the image time separation so as to achieve much larger triangulation baseline than currently possible. Depth is directly derived from the expansion part of the transformation. To a first approximation, image-plane expansion is independent of image-plane location with respect to the focus of expansion (FOE) and of platform maneuvers. Thus, an expansion-based method has the potential of providing a reliable range in the difficult image area around the FOE. In areas far from the FOE the shift parameters of the affine transformation can provide more accurate depth information than the expansion alone, and can thus be used similarly to the way they have been used in conjunction with the Inertial Navigation Unit (INU) and Kalman filtering. However, the performance of a shift-based algorithm, when the shifts are derived from the affine transformation, would be much improved compared to current algorithms because the shifts--as well as the other parameters--can be obtained between widely separated images. Thus, the main advantage of this new approach is that, allowing the tracked window to expand and rotate, in addition to moving laterally, enables one to correlate images over a very long time span which, in turn, translates into a large spatial baseline resulting in a proportionately higher depth accuracy.

Barniv, Yair

1993-01-01

460

Expansion-based passive ranging  

NASA Technical Reports Server (NTRS)

A new technique of passive ranging which is based on utilizing the image-plane expansion experienced by every object as its distance from the sensor decreases is described. This technique belongs in the feature/object-based family. The motion and shape of a small window, assumed to be fully contained inside the boundaries of some object, is approximated by an affine transformation. The parameters of the transformation matrix are derived by initially comparing successive images, and progressively increasing the image time separation so as to achieve much larger triangulation baseline than currently possible. Depth is directly derived from the expansion part of the transformation. To a first approximation, image-plane expansion is independent of image-plane location with respect to the focus of expansion (FOE) and of platform maneuvers. Thus, an expansion-based method has the potential of providing a reliable range in the difficult image area around the FOE. In areas far from the FOE the shift parameters of the affine transformation can provide more accurate depth information than the expansion alone, and can thus be used similarly to the way they were used in conjunction with the Inertial Navigation Unit (INU) and Kalman filter