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1

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

2

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

3

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

National Technical Information Service (NTIS)

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 recon...

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

1996-01-01

4

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

5

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

6

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

NASA Astrophysics Data System (ADS)

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 record the spectra of gamma-rays emitted from within a drum. The ACT attenuation images and the PCT emission spectra are coupled to quantitatively assay drum contents for ˜0.1-200 g of TRU isotopes. Calibration requires a single measurement of a known radioactive standard; construction of waste-drum surrogates is not required. Fixed and mobile systems demonstrated compliance with a DOE quality assurance program via several independent blind tests.

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

2002-12-01

7

The passive nondestructive assay of the plutonium content of spent-fuel assemblies from the BN350 fast-breeder reactor in the city of Aqtau, Kazakhstan  

Microsoft Academic Search

The International Atomic Energy Agency is presently interested in developing equipment and techniques to measure the plutonium content of breeder reactor spent-fuel assemblies located in storage ponds before they are relocated to more secure facilities. We present the first quantitative nondestructive assay of the plutonium content of fast-breeder reactor spent-fuel assemblies while still underwater in their facility storage pond. We

J. P. Lestone; J. M. Pecos; J. A. Rennie; J. K. Sprinkle; P. Staples; K. N. Grimm; R. N. Hill; I. Cherradi; N. Islam; J. Koulikov; Z. Starovich

2002-01-01

8

Mobile Nondestructive Assay Verification and Measurement System.  

National Technical Information Service (NTIS)

A mobile, real-time, nondestructive assay system has been developed for both nuclear material safeguards inventory verifications and measurements on the Hanford project. The system includes electronic and computer support equipment mounted in a specially ...

F. P. Brauer J. E. Fager J. H. Kaye R. J. Sorenson

1977-01-01

9

Nondestructive Techniques for Assaying Fuel Debris in Piping at Three Mile Island Unit 2.  

National Technical Information Service (NTIS)

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...

C. V. McIsaac J. W. Mandler K. Vinjamuri L. Isaacson L. S. Beller

1981-01-01

10

Determining plutonium in spent fuel with nondestructive assay techniques  

SciTech Connect

There are a variety of motivations for quantifying plutonium in used (spent) fuel assemblies by means of nondestructive assay including the following: shipper/receiver difference, input accountability at reprocessing facilities and burnup credit at repositories or fuel storage facilities. Twelve NDA techniques were identified that provide information about the composition of an assembly. Unfortunately, none of these techniques is capable of determining the Pu mass in an assembly on its own. However, it is expected that the Pu mass can be quantified by combining a few of the techniques. Determining which techniques to combine and estimating the expected performance of such a system is the purpose of the research effort recently begun. The research presented here is a complimentarily experimental effort. This paper will focus on experimental results of one of the twelve non-destructive assay techniques - passive neutron albedo reactivity. The passive neutron albedo reactivity techniques work by changing the multiplication the pin experiences between two separate measurements. Since a single spent fuel pin has very little multiplication, this is a challenging measurement situation for the technique. Singles and Doubles neutron count rate were measured at Oak Ridge National Laboratory for three different burnup pins to test the capability of the passive neutron albedo reactivity technique.

Tobin, Stephen J [Los Alamos National Laboratory; Charlton, William S [Los Alamos National Laboratory; Fensin, Michael L [Los Alamos National Laboratory; Menlove, Howard O [Los Alamos National Laboratory; Hoover, A S [Los Alamos National Laboratory; Quiter, B J [Los Alamos National Laboratory; Rajasingam, A [Los Alamos National Laboratory; Swinhoe, M T [Los Alamos National Laboratory; Thompson, S J [Los Alamos National Laboratory; Charlton, W S [TEXAS A& M UNIV; Ehinger, M H [ORNL; Sandoval, N P [ORNL; Saavedra, S F [ORNL; Strohmeyer, D [TEXAS A& M UNIV

2009-01-01

11

Nondestructive assay measurements of GNEP related materials  

SciTech Connect

Because the reprocessing technologies that are currently being considered for the Global Nuclear Energy Partnership (GNEP) will keep various actinides commingled with plutonium at all times throughout the process, the resulting nuclear fuel that is intended for the Advanced Burner Reactor will present unique measurement challenges for the various Nondestructive Assay (NDA) techniques. In order to begin clarifying which types of materials and measurement scenarios that may exist within GNEP require the development of new measurement technologies, an initial series of measurements have been performed on materials with radiation properties that are similar to those being considered within GNEP.

Santi, Peter A [Los Alamos National Laboratory; Crooks, William, J. [Los Alamos National Laboratory; Geist, William, H. [Los Alamos National Laboratory; Gonzales, Robert [Los Alamos National Laboratory; Helland, Carolyn, A. [Los Alamos National Laboratory; Jackson, Jay, M. [Los Alamos National Laboratory; Frame, Katherine, C. [Los Alamos National Laboratory; Martinez, Michael, M. [Los Alamos National Laboratory; Scherer, Caroylnn, P. [Los Alamos National Laboratory; Vo, Duc, T. [Los Alamos National Laboratory

2008-01-01

12

Nondestructive assay methods for solids containing plutonium  

SciTech Connect

Specific nondestructive assay (NDA) methods, e.g. calorimetry, coincidence neutron counting, singles neutron counting, and gamma ray spectrometry, were studied to provide the Savannah River Plant with an NDA method to measure the plutonium content of solid scrap (slag and crucible) generated in the JB-Line plutonium metal production process. Results indicate that calorimetry can be used to measure the plutonium content to within about 3% in 4 to 6 hours by using computerized equilibrium sample power predictive models. Calorimetry results confirm that a bias exists in the present indirect measurement method used to estimate the plutonium content of slag and crucible. Singles neutron counting of slag and crucible can measure plutonium to only +-30%, but coincidence neutron counting methods improve measurement precision to better than +-10% in less than ten minutes. Only four portions of a single slag and crucible sample were assayed, and further study is recommended.

Macmurdo, K.W.; Gray, L.W.; Gibbs, A.

1984-06-01

13

The USDOE mobile non-destructive assay and examination system  

SciTech Connect

A mobile system for non-destructive assay (NDA) and non-destructive examination (NDE), developed at the Los Alamos National Laboratory, provides accurate and sensitive determination of quantities of transuranic (TRU) isotopes contained in 208-/ell/ drums of wastes and furnishes images of the contents for further sorting purposes. The NDA unit consists of four major subsystems: an assay chamber, counting and digital electronics, data acquisition, and a neutron generator. It performs both active and passive neutron measurements for the determination of the amount of fissile isotopes at a sensitivity level of 1 mg plutonium, and the determination of the spontaneous fission and (..cap alpha..,n) isotopes at a comparable level. A complete assay consists of sequential active and passive measurements. The data analysis includes various matrix corrections and a determination that the drum does or does not exceed the 100-nCi/g threshold for TRU wastes. The NDE unit is used to examine for liquids and other materials that are prohibited for long term storage of the drums. An x-ray camera images the contents of 208-/ell/ drums that are brought into the system on a conveyor and rotated in front of an x-ray source. Free liquids can be detected by shaking the drum and observing liquid motion on the video screen. Made to fit on flatbed trailers, the entire system can be transported to a Department of Energy (DOE) facility and be ready for operations within 5 hours after arrival. Field tests have been performed on three separate occasions, accomplishing more than 1800 waste drum examinations. 8 refs., 9 figs., 1 tab.

Dowdy, E.J.

1988-01-01

14

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

15

Shuffler instruments for the nondestructive assay of fissile materials  

SciTech Connect

A shuffler is a nondestructive assay instrument used to determine the fissile content of materials. It places an isotopic source of neutrons near the material to induce fissions, withdraws the source, and counts the delayed neutrons. The source is shuffled until a sufficient number of delayed neutrons have been counted. The shuffler technique is generally applied to difficult assay cases. The amount of material present may be very small (a few milligrams), and thus it does not spontaneously emit neutrons of consequence; the amount of material is also below an active well counter's level of sensitivity. On the other hand, the fissile amount may be fairly large, but the rate of spontaneously emitted neutrons may still be low (so a passive neutron count will not work) or the highest assay precision may be desired (favoring a shuffler over an active well counter) even if the material is inhomogeneous (making it difficult to interrogate with thermal neutrons). In all these cases, gamma-ray backgrounds, self- shielding, or matrix effects can make gamma-ray assays impractical. Materials ranging from highly radioactive spent-fuel assemblies to low-level waste drums have been assayed with shufflers, as have leached hulls, various process materials, scrap, and waste. This report presents a theoretical background for shufflers and describes techniques for practical applications. Procedures for assaying mixtures of fissile isotopes, inhomogeneous materials, and flowing liquids are discussed. It is shown how the precision and limits of detection of a shuffler can be calculated for a given neutron background rate. A section on data analysis gives a stepwise procedure for converting the measured counts into an assay value, including random, systematic, and total uncertainties. 31 refs.

Rinard, P.M.

1991-05-01

16

Nondestructive Assay of Highly Enriched Spent Fuel.  

National Technical Information Service (NTIS)

Passive gamma-ray and neutron measurements have been made on irradiated MTR fuel at the Omega West Reactor. Detectors utilized include a Ge(Li) for gamma spectroscopy, a exp 235 U fission chamber for thermal neutrons, and a smaller exp 235 U fission chamb...

J. R. Phillips S. T. Hsue C. R. Hatcher K. Kaieda E. G. Medina

1978-01-01

17

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

18

Mobile nondestructive assay and examination 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 esily transportable, self-contained modules: one x-rays the contents of special 208-l shipment containers, the other assays the contents. The assay and evaluation system is a simple, portable solution to a complex problem that ensures that only properly packaged transuranic (TRU) wste is shipped to the Department of Energy's Waste Isolation Pilot Plant (WIPP) near Carlsbad, New Mexico. Caustic chemicals, liquids, and other objects or materials tht could cause a container leak during shipment are the objects of an x-ray and video camera used in the system. The camera inspects the contents of 208-l drums that are brought into the system on a conveyor and rotated, one at a time, in front of the x-ray source. Free liquids can be detected by shaking the drum; the sloshing liquid is visible on the video screen. After the drum is x-rayed, it is conveyed to the assay module where precision instruments measure the amounts of TRU isotopes present in the waste. If the drum contains fissile TRU isotopes above the safety limit, it is rejected and sent to an appropriate facility for repackaging; if the drum contains less than the 100 nCi/g lower-level limit for TRU, it is rejected and sent to a low-level nuclear waste burial site. Drums whose contents fall between these limits are accepted and certified for shipment to the WIPP. Made to fit on flatbed trailers, the entire system can be transported to a DOE facility and be ready for operations within 5 hours after arrival.

Bieri, J.M.; Caldwell, J.T.; Audas, J.H.; Butterfield, K.B.; France, S.W.; Garcia, C. Jr.; Hastings, R.D.; Herrera, G.C.; Kuckertz, T.H.; Kunz, W.E.

1986-01-01

19

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

20

Conceptual Ideas for New Nondestructive UF6 Cylinder Assay Techniques  

Microsoft Academic Search

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 UFâ in the cylinder combined with a gamma-ray measurement of the 186 keV peak from ²³⁵U to determine enrichment. More recently,

Karen A

2012-01-01

21

Utility of neural networks in nondestructive waste assay measurement methods  

SciTech Connect

Concepts devised to utilize nondestructive assay measurement techniques to quantify waste entrained radioactive material mass, transuranic and otherwise, must necessarily contain provisions for complexity. Such complexities are founded in the multi-variate attribute distributions associated with the typical waste form and the inherently limited nature of present-day nondestructive assay (NDA) sensors and detection techniques. For many waste forms, the attribute variables are such that commonly employed NDA techniques do not possess the capability to acquire accurate measures useful in deriving a viable solution using first principle modeling techniques. The existence of limitations in commonly employed NDA instrumentation and techniques logically leads to a search for an alternate view or paradigm for data treatment. The approach addressed in this paper shifts from model-driven algorithmic methods to data-driven empirical methods. Such empirical methods are statistical in nature, and possess desirable characteristics of adaptivity and learning. Examples of modern empirical methods include neural networks, fuzzy logic, genetic algorithms, and combinations thereof. This work provides an investigation into the utility of three neural network architectures for deriving useful information for nondestructive waste assay solutions. To illustrate the inherent capability of these data-driven techniques, a simple waste form classification exercise is performed using radial basis function, counterpropagation, and adaptive resonance theory neural networks. The classifications are derived solely from the self-organizing and adaptation capabilities of the network architectures and associated learning rules. No apriori information or models are assumed during the classification exercises.

Becker, G.K.; Roney, T.J. [Idaho National Engineering Lab., Idaho Falls, ID (United States); Watts, C.L. [Idaho State Univ., Pocatello, ID (United States)] [and others

1995-12-01

22

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

23

Preparation of pure neptunium oxide for nondestructive assay standards  

SciTech Connect

Accurate nondestructive assay (NDA) measurements, particularly with gamma spectrometry, require pure material standards. The purity of materials used as standards is verified by reliable chemical techniques, and these materials are then used to calibrate and certify NDA instruments. So that they can be used for this purpose, impure NpO{sub 2} and metal were each purified by a different procedure. The NpO{sub 2}, which contained more than 2500 ppm plutonium, was purified by a double peroxide precipitation, followed by ion exchange and oxalate precipitation of the eluate. All impurities, including plutonium, were below 10 ppm in the product. The metal, which contained more than 10,000 ppm of tantalum, was dissolved in 12 M HCl and then precipitated as the Np(4) oxalate. The final product was below 100 ppm of all impurities except calcium. 1 ref., 2 tabs.

Yarbro, S.L.; Dunn, S.L.; Schreiber, S.B.

1991-03-01

24

Performance characteristics of a High Efficiency Passive Neutron Assay System using alternative neutron detectors to helium-3  

Microsoft Academic Search

Passive neutron non-destructive assay systems demand high sensitivity in order to be capable of detecting milligram levels of plutonium for safeguards and waste characterization applications. Chamber efficiencies greater than 30% are required for neutron coincidence and multiplicity counting systems. Existing systems are based on 3He proportional counters and require hundreds of liters of this gas. The severe 3He shortage has

A. P. Simpson; S. Jones; M. J. Clapham; S. A. McElhaney

2011-01-01

25

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

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 assay and nondestructive examination of remote-handled transuranic waste at the ORNL waste handling and packaging plant  

SciTech Connect

The purpose of this investigation is to examine the use of an electron linear accelerator (LINAC) in the performance of nondestructive assay (NDA) and nondestructive examination (NDE) measurements of remote-handled transuranic wastes. The system will be used to perform waste characterization and certification activities at the Oak Ridge National Laboratory's proposed Waste Handling and Packaging Plant. The NDA and NDE technologies which were developed for contact-handled wastes are inadequate to perform such measurements on high gamma and neutron dose-rate wastes. A single LINAC will provide the interrogating fluxes required for both NDA and NDE measurements of the wastes. 11 refs., 6 figs.

Schultz, F.J.; Caldwell, J.T. (Oak Ridge National Lab., TN (USA); Pajarito Scientific Corp. (USA))

1989-01-01

28

Preliminary report of the comparison of multiple non-destructive assay techniques on LANL Plutonium Facility waste drums  

SciTech Connect

Prior to disposal, nuclear waste must be accurately characterized to identify and quantify the radioactive content. The DOE Complex faces the daunting task of measuring nuclear material with both a wide range of masses and matrices. Similarly daunting can be the selection of a non-destructive assay (NDA) technique(s) to efficiently perform the quantitative assay over the entire waste population. In fulfilling its role of a DOE Defense Programs nuclear User Facility/Technology Development Center, the Los Alamos National Laboratory Plutonium Facility recently tested three commercially built and owned, mobile nondestructive assay (NDA) systems with special nuclear materials (SNM). Two independent commercial companies financed the testing of their three mobile NDA systems at the site. Contained within a single trailer is Canberra Industries segmented gamma scanner/waste assay system (SGS/WAS) and neutron waste drum assay system (WDAS). The third system is a BNFL Instruments Inc. (formerly known as Pajarito Scientific Corporation) differential die-away imaging passive/active neutron (IPAN) counter. In an effort to increase the value of this comparison, additional NDA techniques at LANL were also used to measure these same drums. These are comprised of three tomographic gamma scanners (one mobile unit and two stationary) and one developmental differential die-away system. Although not certified standards, the authors hope that such a comparison will provide valuable data for those considering these different NDA techniques to measure their waste as well as the developers of the techniques.

Bonner, C.; Schanfein, M.; Estep, R. [and others

1999-03-01

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 of Nuclear Low-Enriched Uranium Spent Fuels for Burnup Credit Application  

SciTech Connect

Criticality safety analysis devoted to spent-fuel storage and transportation has to be conservative in order to be sure no accident will ever happen. In the spent-fuel storage field, the assumption of freshness has been used to achieve the conservative aspect of criticality safety procedures. Nevertheless, after being irradiated in a reactor core, the fuel elements have obviously lost part of their original reactivity. The concept of taking into account this reactivity loss in criticality safety analysis is known as burnup credit. To be used, burnup credit involves obtaining evidence of the reactivity loss with a burnup measurement.Many nondestructive assays (NDA) based on neutron as well as on gamma-ray emissions are devoted to spent-fuel characterization. Heavy nuclei that compose the fuels are modified during irradiation and cooling. Some of them emit neutrons spontaneously, and the link to burnup is a power link. As a result, burnup determination with passive neutron measurement is extremely accurate.Some gamma emitters also have interesting properties in order to characterize spent fuels, but the convenience of the gamma spectrometric methods is very dependent on the characteristics of the spent fuel. In addition, contrary to the neutron emission, the gamma signal is mostly representative of the peripheral rods of the fuels.Two devices based on neutron methods but combining different NDA methods which have been studied in the past are described in detail:1. The PYTHON device is a combination of a passive neutron measurement, a collimated total gamma measurement, and an online depletion code. This device, which has been used in several nuclear power plants in western Europe, gives the average burnup within a 5% uncertainty and also the extremity burnup.2. The NAJA device is an automatic device that involves three nuclear methods and an online depletion code. It is designed to cover the whole fuel assembly panel (active neutron interrogation, passive neutron counting, and gamma spectrometry)

Lebrun, Alain; Bignan, Gilles [Commissariat a l'Energie Atomique CEA (France)

2001-09-15

31

Nondestructive assay using active and passive computed tomography.  

National Technical Information Service (NTIS)

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. T...

G. Roberson

1998-01-01

32

Some target assay uncertainties for passive neutron coincidence counting  

Microsoft Academic Search

This paper provides some target assay uncertainties for passive neutron coincidence counting of plutonium metal, oxide, mixed oxide, and scrap and waste. The target values are based in part on past user experience and in part on the estimated results from new coincidence counting techniques that are under development. The paper summarizes assay error sources and the new coincidence techniques,

N. Ensslin; D. G. Langner; H. O. Menlove; M. C. Miller; P. A. Russo

1990-01-01

33

Nondestructive assay of spent fuel rods from a Light Water Breeder Reactor (LWBR Development Program)  

Microsoft Academic Search

A gauge, called the Production Irradiated Fuel Assay Gauge (PIFAG), has been developed and utilized to measure, nondestructively, the fissile fuel content of spent fuel rods from the Light Water Breeder Reactor (LWBR) core. The PIFAG was in operation from November 1983 to May 1987. During this period, assay data were obtained for two irradiated test rods used for initial

G. Tessler; B. R. Beaudoin; W. J. Beggs; L. B. Freeman; W. C. Jr. Schick

1987-01-01

34

Some target assay uncertainties for passive neutron coincidence counting  

SciTech Connect

This paper provides some target assay uncertainties for passive neutron coincidence counting of plutonium metal, oxide, mixed oxide, and scrap and waste. The target values are based in part on past user experience and in part on the estimated results from new coincidence counting techniques that are under development. The paper summarizes assay error sources and the new coincidence techniques, and recommends the technique that is likely to yield the lowest assay uncertainty for a given material type. These target assay uncertainties are intended to be useful for NDA instrument selection and assay variance propagation studies for both new and existing facilities. 14 refs., 3 tabs.

Ensslin, N.; Langner, D.G.; Menlove, H.O.; Miller, M.C.; Russo, P.A.

1990-01-01

35

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

36

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

Microsoft Academic Search

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

2000-01-01

37

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

Microsoft Academic Search

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

M. G. CANTALOUB; C. E. WILLS

2000-01-01

38

Guide to nondestructive assay standards: Preparation criteria, availability, and practical considerations  

Microsoft Academic Search

For certification and measurement control, nondestructive assay (NDA) instruments and methods used for verification measurement of special nuclear materials (SNMs) require calibrations based on certified reference materials (CRMs), or working reference materials (WRMs), traceable to the national system of measurements, and adequately characteristic of the unknowns. The Department of Energy Office of Safeguards and Security is sponsoring production of a

J. E. Stewart; S. T. Hsue; T. E. Sampson

1997-01-01

39

Guide to nondestructive assay standards: Preparation criteria, availability, and practical considerations  

Microsoft Academic Search

For certification and measurement control, nondestructive assay (NDA) instruments and methods used for verification measurements of special nuclear materials (SNMs) require calibrations based on certified reference materials (CRMs), or working reference materials (WRMs), traceable to the national system of measurements, and adequately characteristic of the unknowns. The Department of Energy Office of Safeguards and Security is sponsoring production of a

S. T. Hsue; J. E. Stewart; T. E. Sampson; G. W. Butler; C. R. Rudy; P. M. Rinard

1997-01-01

40

Interlaboratory comparison program for nondestructive assay of prototype uranium reference materials  

Microsoft Academic Search

The US Department of Energy (DOE), New Brunswick Laboratory (NBS), designed and administered an interlaboratory comparison program based on the measurement of NBL-produced prototype uranium nondestructive assay (NDA) reference materials for scrap and waste. The objectives of the program were to evaluate the reliability of NDA techniques as applied to nuclear safeguards materials control and accountability needs and to investigate

N. M. Trahey; M. M. Smith; A. M. Voeks; J. T. Bracey

1986-01-01

41

Microfluidic passive permeability assay using nanoliter droplet interface lipid bilayers.  

PubMed

Membrane permeability assays play an important role in assessing drug transport activities across biological membranes. However, in conventional parallel artificial membrane permeability assays (PAMPA), the membrane model used is dissimilar to biological membranes physically and chemically. Here, we describe a microfluidic passive permeability assay using droplet interface bilayers (DIBs). In a microfluidic network, nanoliter-sized donor and acceptor aqueous droplets are alternately formed in cross-flowing oil containing phospholipids. Subsequently, selective removal of oil through hydrophobic pseudo-porous sidewalls induces the contact of the lipid monolayers, creating arrayed planar DIBs between the donor and acceptor droplets. Permeation of fluorescein from the donor to the acceptor droplets was fluorometrically measured. From the measured data and a simple diffusion model we calculated the effective permeabilities of 5.1 × 10(-6) cm s(-1), 60.0 × 10(-6) cm s(-1), and 87.6 × 10(-6) cm s(-1) with donor droplets at pH values of 7.5, 6.4 and 5.4, respectively. The intrinsic permeabilities of specific monoanionic and neutral fluorescein species were obtained similarly. We also measured the permeation of caffeine in 10 min using UV microspectroscopy, obtaining a permeability of 20.8 × 10(-6) cm s(-1). With the small solution volumes, short measurement time, and ability to measure a wide range of compounds, this device has considerable potential as a platform for high-throughput drug permeability assays. PMID:24056299

Nisisako, Takasi; Portonovo, Shiva A; Schmidt, Jacob J

2013-11-21

42

Nondestructive assay of spent fuel rods from a Light Water Breeder Reactor (LWBR Development Program)  

SciTech Connect

A gauge, called the Production Irradiated Fuel Assay Gauge (PIFAG), has been developed and utilized to measure, nondestructively, the fissile fuel content of spent fuel rods from the Light Water Breeder Reactor (LWBR) core. The PIFAG was in operation from November 1983 to May 1987. During this period, assay data were obtained for two irradiated test rods used for initial qualification of the gauge and 524 spent LWBR core rods. A review of PIFAG operations is given, including hot cell operations, calibration, assay operations, and methods used to monitor the data quality and verify the precision and accuracy of the data. The analytical model used to determine the core rod fissile fuel content from the data and the results for the 524 LWBR spent fuel rods are given.

Tessler, G.; Beaudoin, B.R.; Beggs, W.J.; Freeman, L.B.; Schick, W.C. Jr.

1987-09-01

43

Effects of Surface Passivation on Gliding Motility Assays  

PubMed Central

In this study, we report differences in the observed gliding speed of microtubules dependent on the choice of bovine casein used as a surface passivator. We observed differences in both speed and support of microtubules in each of the assays. Whole casein, comprised of ?s1, ?s2, ?, and ? casein, supported motility and averaged speeds of 966±7 nm/s. Alpha casein can be purchased as a combination of ?s1 and ?s2 and supported gliding motility and average speeds of 949±4 nm/s. Beta casein did not support motility very well and averaged speeds of 870±30 nm/s. Kappa casein supported motility very poorly and we were unable to obtain an average speed. Finally, we observed that mixing alpha, beta, and kappa casein with the proportions found in bovine whole casein supported motility and averaged speeds of 966±6 nm/s.

Maloney, Andy; Herskowitz, Lawrence J.; Koch, Steven J.

2011-01-01

44

Direct Actinide Assay with Surface Passivated Silicon Diodes  

SciTech Connect

The determination of transuranic (TRU) content in nuclear wastes, reactor materials, process solutions, and various other matrices is required in support of material assessment, environmental restoration and waste processing activities. We have found that direct measurements of TRU is possible using passivated implanted planar silicon (PIPS) diode detectors. The performance and durability of the modern PIPS diodes enables direct detection of alpha particles, with retention of some spectral information, through small air gaps or under direct contact with liquid or solid samples. Direct assay of solutions and materials can provide rapid data solutions with high-levels or beta/gamma emitters in remote locations without human exposure or waste generation issues. Result are given on performance of PIPS detectors for the determination of TRUs in liquid and solid samples.

Addleman, Raymond S.; O'Hara, Matthew J.; Marks, Todd D.; Grate, Jay W.; Egorov, Oleg B.

2005-01-01

45

Use of Calibration Standards and the Correction for Sample Self-Attenuation in gamma-Ray Nondestructive Assay.  

National Technical Information Service (NTIS)

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 rel...

J. L. Parker

1986-01-01

46

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

47

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

48

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

49

Guide to nondestructive assay standards: Preparation criteria, availability, and practical considerations  

SciTech Connect

For certification and measurement control, nondestructive assay (NDA) instruments and methods used for verification measurements of special nuclear materials (SNMs) require calibrations based on certified reference materials (CRMs), or working reference materials (WRMs), traceable to the national system of measurements, and adequately characteristic of the unknowns. The Department of Energy Office of Safeguards and Security is sponsoring production of a comprehensive guide to preparation of NDA standards. The scope of the report includes preparation criteria, current availability of CRMs and WRMs, practical considerations for preparation and characterization, and an extensive bibliography. In preparing the report, based primarily on experience at Los Alamos, they have found that standards preparation is highly dependent on the particular NDA method being applied. They therefore include sections that contain information specific to commonly used neutron and gamma-ray NDA techniques. They also present approaches that are alternatives to, or minimize requirements for physical standards.

Hsue, S.T.; Stewart, J.E.; Sampson, T.E.; Butler, G.W.; Rudy, C.R.; Rinard, P.M.

1997-10-01

50

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

51

Remote-controlled NDA (nondestructive assay) systems for process areas in a MOX (mixed oxide) facility  

SciTech Connect

Nondestructive assay (NDA) systems have been designed and installed in the process area of an automated mixed-oxide (MOX) fuel fabrication facility. These instruments employ neutron coincidence counting methods to measure the spontaneous-fission rate of plutonium in the powders, pellets, and fuel pins in the process area. The spontaneous fission rate and the plutonium isotopic ratios determine the mass of plutonium in the sample. Measurements can be either attended or unattended. The fuel-pin assay system (FPAS) resides above the robotic conveyor system and measures the plutonium content in fuel-pin trays containing up to 24 pins (/approximately/1 kg of plutonium). The material accountancy glove-box (MAGB) counters consist of two slab detectors mounted on the sides of the glove box to measure samples of powder or pellets as they are brought to the load cell. Samples measured by the MAGB counters may contain up to 18 kg of MOX. This paper describes the design and performance of four systems: the fuel-pin assay system and three separate MAGB systems. The paper also discusses the role of Monte Carlo transport techniques in the detector design and subsequent instrument calibration. 5 refs., 11 figs., 6 tabs.

Miller, M.C.; Menlove, H.O.; Augustson, R.H.; Ohtani, T.; Seya, M.; Takahashi, S.; Abedin-Zadeh, R.

1989-01-01

52

Prototype Radiation Detector Positioning System For The Automated Nondestructive Assay Of Uf6 Cylinders  

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 efficiency and assay accuracy. This paper describes an approach denoted the Integrated Cylinder Verification Station (ICVS) that supports 100% cylinder verification, provides volume-averaged cylinder enrichment assay, and reduces inspector manpower needs. To allow field measurements to be collected to validate data collection algorithms, a prototype radiation detector positioning system was constructed. The system was designed to accurately position an array of radiation detectors along the length of a cylinder to measure UF6 enrichment. A number of alternative radiation shields for the detectors were included with the system. A collimated gamma-ray spectrometer module that allows translation of the detectors in the surrounding shielding to adjust the field of view, and a collimating plug in the end to further reduce the low-energy field of view, were also developed. Proof-of-principle measurements of neutron and high-energy gamma-ray signatures, using moderated neutron detectors and large-volume spectrometers in a fixed-geometry, portal-like configuration, supported an early assessment of the viability of the concept. The system has been used successfully on two testing campaigns at an AREVA fuel fabrication plant to scan over 30 product cylinders. This paper will describe the overall design of the detector positioning system and provide an overview of the Integrated Cylinder Verification Station (ICVS) approach.

Hatchell, Brian K.; Valdez, Patrick LJ; Orton, Christopher R.; Mace, Emily K.

2011-08-07

53

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

54

An integrated Tomographic Gamma Scanning system for non-destructive assay of radioactive waste  

NASA Astrophysics Data System (ADS)

The Tomographic Gamma Scanning (TGS) technique is a relatively new method in the field of non-destructive assay (NDA) of radioactive waste. The TGS technique combines High Resolution Gamma Spectrometry (HRGS) with Three-Dimensional (3-D) low spatial resolution transmission and emission image reconstruction techniques to achieve assay goals. When compared to the traditional methods such as Segmented Gamma Scanning (SGS), the TGS technique can yield better accuracies for cases where the radionuclide is distributed non-uniformly in a heterogeneous matrix. The TGS technique is ideally suited for low-to-moderate density waste matrices, say 1.0 g cm -3 or below for 55 US gal. drums, although it can be extended to higher densities by using alternative approaches to the design or analyses. Recently Canberra Industries designed, built and characterized four such TGS systems for nuclear power plant applications. Many of the design features and the end application itself set these TGS systems apart from the others that had been built previously. The four TGS systems are the first commercial grade systems that could quantify radionuclides contained in nuclear power plant waste, using the TGS technique. The TGS systems featured two different combinations of collimator and source-detector distance; a "near" geometry with a collimator aperture of 50.8 mm and a "Far" geometry with a narrower collimator aperture of 40.6 mm. For assaying drums with matrix densities greater than 1.0 g cm -3 and/or dose rates greater than 6 mSv h -1 the system could be configured as a SGS. In the SGS mode, five different assay geometries could be configured using different collimator, source-to-detector distance and absorber combinations. During operation, the appropriate assay geometry was selected automatically based on the drum weight (density) and dose rate measurements. The characterization and performance of the one of the TGS systems are discussed in detail for both TGS and SGS modes of operation. Quantitative results are presented for point source and rod source nuclide distributions. Transmission and emission images obtained in the TGS assays will be presented.

Venkataraman, Ramkumar; Villani, Marcel; Croft, Stephen; McClay, Patricia; McElroy, Robert; Kane, Susan; Mueller, Wilhelm; Estep, Robert

2007-08-01

55

Total Measurement Uncertainty (TMU) for Nondestructive Assay of Transuranic (TRU) Waste at the WRAP Facility  

SciTech Connect

At the WRAP facility, there are two identical imaging passive/active neutron (IPAN) assay systems and two identical gamma energy assay (GEA) systems. Currently, only the GEA systems are used to characterize waste, therefore, only the GEA systems are addressed in this document. This document contains the limiting factors relating to the waste drum analysis for shipments destined for WIPP. The TMU document provides the uncertainty basis in the NDA analysis of waste containers at the WRAP facility. The defined limitations for the current analysis scheme are as follows: The WRAP waste stream debris is from the Hanford Plutonium Finishing Plant's process lines, primarily combustible materials. Plutonium analysis range is from the minimum detectable concentration (MDC), Reference 6, to 160 grams (8). The GEA system calibration density ranges from 0.013 g/cc to 1.6 g/cc. PDP Plutonium drum densities were evaluated from 0.065 g/cc to 0.305 gkc. PDP Plutonium source weights ranged from 0.030 g to 3 18 g, in both empty and combustibles matrix drums. The GEA system design density correction macroscopic absorption cross section table (MAC) is Lucite, a material representative of combustible waste. Drums with material not fitting the debris waste criteria are targeted for additional calculations, reviews, and potential re-analysis using a calibration suited for the waste type.

CANTALOUB, M.G.

2000-05-22

56

Non-Destructive Detection of Rebar Buried in a Reinforced Concrete Wall with Wireless Passive SAW Sensor  

NASA Astrophysics Data System (ADS)

In order to reduce the damage to the old reinforced concrete walls and work out the best construction scheme during the renovation of old buildings, it is often required to detect the position of rebar buried in concrete walls. In this paper, we propose a non-destructive method to detect the buried rebar by self-inductive sensor combined with surface acoustic wave resonator (SAWR). The proposed method has the advantages of wireless, passive and convenient operations. In our new design, the sensing element of self-inductance coil was made as a component of SAWR matching network. The distribution of rebar could be measured according to the system resonant frequency, using a signal demodulation device set. The depth of buried rebar and the deviation of output resonant frequency from inherent frequency of SAWR have an inverse relation. Finally, the validity of the method was verified in theoretical calculation and simulation.

Fan, Yanping; Ji, Xiaojun; Cai, Ping; Lu, Qianhui

2013-01-01

57

Total Measurement Uncertainty (TMU) for Nondestructive Assay of Transuranic (TRU) Waste at the 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 Hanford's 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 (Reference 1). Various programs exist to ensure the validity of waste characterization data; all of these cite the need for clearly defined knowledge of uncertainty, associated with any measurements taken. All measurements have an inherent uncertainty associated with them. The combined effect of all uncertainties associated with a measurement is referred to as the Total Measurement Uncertainty (TMU). The NDA measurement uncertainties can be numerous and complex. In addition to system-induced measurement uncertainty, other factors contribute to the TMU, each associated with a particular measurement. The NDA measurements at WRAP are based on processes (radioactive decay and induced fission) which are statistical in nature. As a result, the proper statistical summation of the various uncertainty components is essential. This report examines the contributing factors to NDA measurement uncertainty at WRAP. The significance of each factor on the TMU is analyzed, and a final method is given for determining the TMU for NDA measurements at WRAP. As more data becomes available, and WRAP gains in operational experience, this report will be reviewed semi-annually and updated as necessary. This report also includes the data flow paths for the analytical process in the radiometric determinations.

WILLS, C.E.

2000-02-24

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

Nondestructive assay of spent nuclear fuel with gamma-ray spectroscopy  

Microsoft Academic Search

An important issue in nuclear safeguards is to verify operator-declared data of spent nuclear fuel. Various techniques have therefore been assigned for this purpose. A nondestructive approach is to measure the gamma radiation from spent nuclear fuel assemblies. Using this technique, parameters such as burnup and cooling time can be calculated or verified.In this paper, we propose the utilization of

Christofer Willman; Ane Håkansson; Otasowie Osifo; Anders Bäcklin; Staffan Jacobsson Svärd

2006-01-01

61

Statistical signal processing and artificial intelligence applications in the nondestructive assay of U/Pu bearing materials  

SciTech Connect

Over the years a number of techniques have been developed to determine the quantity and distribution of radiative isotopes contained in given assay samples through the measurement and analysis of penetrating characteristic radiations. An active technique of particular utility when assaying samples containing very small quantities of fissionable material or when high gamma ray backgrounds are encountered is the delayed neutron nondestructive assay (DN-NDA) technique. Typically, analysis of the delayed neutron signal involves relating the gross delayed neutron count observed following neutron irradiation of an assay sample to total fissionable material present via a linear calibration curve. In this way, the technique is capable of yielding the mass of a single dominant fissionable isotope or the total fissionable mass contained in a sample. Using this approach the only way to determine the mass of individual fissionable isotopes contained in a sample is to correlate total fissionable mass to individual isotopics via calculations or other means, yielding an indirect measure of isotopics. However, there is isotope specific information in the temporal delayed neutron signal due to differences in the delayed neutron precursor yields resulting from the fissioning of different isotopes. The authors present the results of an analysis to evaluate the feasibility of using Kalman filters and genetic algorithms to determine multiple specific fissionable isotopic masses contained in an assay sample from a cumulative delayed neutron signal measured following neutron irradiation of the sample.

Aumeier, S.E.; Forsmann, J.H.

1997-10-01

62

Neutron Resonance Transmission Analysis (NRTA): A Nondestructive Assay Technique for the Next Generation Safeguards Initiative’s Plutonium Assay Challenge  

SciTech Connect

This is an end-of-year report for a project funded by the National Nuclear Security Administration's Office of Nuclear Safeguards (NA-241). The goal of this project is to investigate the feasibility of using Neutron Resonance Transmission Analysis (NRTA) to assay plutonium in commercial light-water-reactor spent fuel. This project is part of a larger research effort within the Next-Generation Safeguards Initiative (NGSI) to evaluate methods for assaying plutonium in spent fuel, the Plutonium Assay Challenge. The first-year goals for this project were modest and included: 1) developing a zero-order MCNP model for the NRTA technique, simulating data results presented in the literature, 2) completing a preliminary set of studies investigating important design and performance characteristics for the NRTA measurement technique, and 3) documentation of this work in an end of the year report (this report). Research teams at Los Alamos National Laboratory (LANL), Lawrence Berkeley National Laboratory (LBNL), Pacific Northwest National Laboratory (PNNL), and at several universities are also working to investigate plutonium assay methods for spent-fuel safeguards. While the NRTA technique is well proven in the scientific literature for assaying individual spent fuel pins, it is a newcomer to the current NGSI efforts studying Pu assay method techniques having just started in March 2010; several analytical techniques have been under investigation within this program for two to three years or more. This report summarizes a nine month period of work.

J. W. Sterbentz; D. L. Chichester

2010-12-01

63

Statistical signal processing and artificial intelligence applications in the nondestructive assay of U/Pu-bearing materials  

SciTech Connect

Over the years, a number of techniques have been developed to determine the quantity and distribution of radiative isotopes contained in given assay samples through the measurement and analysis of penetrating characteristic radiations. An active technique of particular utility when assaying samples containing very small quantities of fissionable material or when high-gamma-ray backgrounds are encountered is the delayed neutron nondestructive assay technique. The authors present the results of an analysis to evaluate the feasibility of using Kalman filters and genetic algorithms to determine multiple specific fissionable isotopic masses contained in an assay sample from a cumulative delayed neutron signal measured following neutron irradiation of the sample. Delayed neutron measurement data were generated to simulate the ideal response of the leached fuel clad monitor located at Argonne National Laboratory-West. The simulated measurement data were generated by calculating the cumulative delayed neutron count following the irradiation of a sample containing 5.9 g {sup 238}U, 9.8 g {sup 235}U, 16.9 G {sup 239}Pu, and 3.1 g {sup 240}Pu. Data were simulated for {approximately} 14-MeV neutron irradiation and irradiation with a moderated neutron beam with average neutron energy of {approximately} 200 eV, which yields a larger fissile/fertile fission ratio than the 14-MeV irradiation.

Aumeier, S.E.; Forsmann, J.H. [Argonne National Lab., Idaho Falls, ID (United States)

1998-09-01

64

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

65

NDA (Non-Destructive Assay) Techniques for Irradiated Fissile Material in Varying Configurations. Final Report for the Period 1 March 1977 - 28 February 1978.  

National Technical Information Service (NTIS)

A Non-Destructive Assay system is presented for the direct determination of irradiated fissile material in extended waste boxes and fuel elements. It is based on active neutron interrogation with an Sb-Be neutron source and specific attenuation of the sou...

R. Filss

1978-01-01

66

Conceptual design for a receiving station for the nondestructive assay of PuOâ at the fuels and materials examination facility  

Microsoft Academic Search

We propose a conceptual design for a receiving station for input accountability measurements on PuOâ received at the Fuels and Materials Examination Facility at the Hanford Engineering Development Laboratory. Nondestructive assay techniques are proposed, including neutron coincidence counting, calorimetry, and isotopic determination by gamma-ray spectroscopy, in a versatile data acquisition system to perform input accountability measurements with precisions better than

T. E. Sampson; L. G. Speir; N. Ensslin; S. T. Hsue; S. S. Johnson; S. Bourret; J. L. Parker

1981-01-01

67

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

Microsoft Academic Search

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

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

1985-01-01

68

Mixed Waste Focus Area/Characterization Monitoring Sensor Technology Nondestructive Waste Assay Capability Evaluation Project End-User Summary Report  

SciTech Connect

The Mixed Waste Focus Area (MWFA) in conjunction with the Characterization Monitoring and Sensor Technology (CMST) crosscut program identified the need to objectively evaluate the capability of nondestructive waste assay (NDA) technologies. This was done because of a general lack of NDA technology performance data with respect to a representative cross section of waste form configurations comprising the Department of Energy (DOE) contact-handled alpha contaminated [e.g., transuranic (TRU) waste]. The overall objective of the Capability Evaluation Project (CEP) was to establish a known and unbiased NDA data and information base that can be used to support end-user decisions with regards to technology system selection and to support technology development organizations in identifying technology system deficiencies. The primary performance parameters evaluated in the CEP were measurement bias and relative precision. The performance of a given NDA technology is a direct function of the attributes represented by the waste matrix configuration. Such attributes include matrix density, matrix elemental composition, radionuclidic composition, radionuclide mass loading, and the spatial variation of these components. Analyzing the manner in which bias and precision vary as a function of test sample attribute and NDA technology provides a foundation for deriving performance capability and limitation statements and determines which waste matrix attributes, or combinations of attributes, are compatible or incompatible with existing technologies. The CEP achieved the stated end-user objective. The data indicate that the nondestructive waste assay systems evaluated have a definite capability to perform assay of contact-handled TRU waste packaged in 55-gallon drums. There is, however, a performance envelope where this capability exists, an area near the envelope boundaries where it is questionable, and a realm outside the envelope where the technologies do not perform. Therefore, the end user must be aware of this envelope and ensure the appropriate technology is selected. This program provides the end user with waste type specific performance data to assist in the assessment and selection of a given waste NDA technology. Additionally, the CEP afforded the private sector participants the opportunity to evaluate system performance using National Institute of Standards and Technology traceable radioactive significant enhancements to their respective systems and supported all participants in attaining DOE-CAO certification. Ultimately, the DOE end users will benefit from these enhancements.

G. K. Becker; M. E. McIlwain; M. J. Connolly

1998-11-01

69

Nondestructive assay of plutonium and minor actinide in spent fuel using nuclear resonance fluorescence with laser Compton scattering ?-rays  

NASA Astrophysics Data System (ADS)

We propose a new nondestructive assay method for 235U, 239Pu, and minor actinides in spent nuclear fuel assembly in a water pool. Nuclear fuel materials are detected using nuclear resonance fluorescence (NRF) with laser Compton scattering (LCS) ?-rays. The NRF assay can provide a finger print of each isotope since the NRF ?-ray energy is characteristic of a specific nuclide. We design a high-flux LCS ?-ray source, in which ?-rays are generated by collision of laser photons provided from Yb-doped fiber laser and electrons from energy recovery linac. This system has following advantages; this can detect isotopes of most elements behind heavy materials such as uranium of a thickness of several centimeters, and analyze the fuel assembly in a water pool. A simulation calculation shows that we can detect 1% fraction 239Pu in all the fuel rods with statistical error lower than 2% using the high flux LCS ?-ray source and the measurement time of 4000 s.

Hayakawa, Takehito; Kikuzawa, Nobuhiro; Hajima, Ryoichi; Shizuma, Toshiyuki; Nishimori, Nobuyuki; Fujiwara, Mamoru; Seya, Michio

2010-09-01

70

REBOCOL (Robotic Calorimetry): An automated NDA (Nondestructive assay) calorimetry and gamma isotopic system  

SciTech Connect

ROBOCAL, which is presently being developed and tested at Los Alamos National Laboratory, is a full-scale, prototypical robotic system, for remote calorimetric and gamma-ray analysis of special nuclear materials. It integrates a fully automated, multi-drawer, vertical stacker-retriever system for staging unmeasured nuclear materials, and a fully automated gantry robot for computer-based selection and transfer of nuclear materials to calorimetric and gamma-ray measurement stations. Since ROBOCAL is designed for minimal operator intervention, a completely programmed user interface and data-base system are provided to interact with the automated mechanical and assay systems. The assay system is designed to completely integrate calorimetric and gamma-ray data acquisition and to perform state-of-the-art analyses on both homogeneous and heterogeneous distributions of nuclear materials in a wide variety of matrices. 10 refs., 10 figs., 4 tabs.

Hurd, J.R.; Bonner, C.A.; Ostenak, C.A.; Phelan, P.F.; Powell, W.D.; Sheer, N.L.; Schneider, D.N.; Staley, H.C.

1989-01-01

71

Non-destructive assay of ²⁴²Pu by resonance neutron capture  

Microsoft Academic Search

For the accurate assay of plutonium by neutron correlation measurements, especially for material derived from high-burnup reactor fuel, the content of ²⁴²Pu in a sample must be determined. Since ²⁴²Pu has a long half-life (387,000 yr) and decays to ²³⁸U by alpha particle emission with the accompanying emission of only weak, low-energy gamma rays, gamma-ray spectrometry methods which are ordinarily

W. R. Kane; Ming-Shih Lu; A. Aronson; L. Forman; P. E. Vanier

1995-01-01

72

Reversed passive latex agglutination assay for detection of toxigenic Corynebacterium diphtheriae.  

PubMed Central

A reversed passive latex agglutination (RPLA) assay for determining the toxigenicity of Corynebacterium diphtheriae is presented. Rabbit antitoxin antiserum was raised by using commercially available diphtheria toxoid. This antiserum reacted with the diphtheria toxin when the culture supernatant was assayed by Western blotting, and it did not cross-react with other extracellular antigens. Affinity-purified antibodies for latex sensitization were obtained by using a Hi Trap N-hydroxysuccinimide-activated column. Demonstration of toxin in five of seven clinical isolates was in accordance with the PCR assay and the Vero cell cytotoxicity test. Culture of the bacteria for 6 h was sufficient for toxin production, and an additional 6 h was needed to observe latex agglutination. Therefore, diphtheria toxin can be detected in 12 h by this method. The lowest concentration of diphtheria toxin detectable by the RPLA assay was about 5 ng/ml. The RPLA assay can provide a convenient and reliable method for laboratories involved in the identification of toxinogenic corynebacteria.

Toma, C; Sisavath, L; Iwanaga, M

1997-01-01

73

Evaluation of modified passive haemagglutination assay for Vi antibody estimation in Salmonella typhi infections.  

PubMed

A simple passive haemmagglutination assay (PHA) was developed to detect Vi antibodies, to improve the diagnosis of typhoid fever by small laboratories. The Vi capsular antigen of Salmonella typhi was extracted by alternate alcohol and acetone precipitation. Formalin fixed, sheep red blood cells treated with chromium chloride were sensitised with this Vi antigen and antibodies detected and measured by PHA. The test had a sensitivity of 83.3% among 30 cases of typhoid fever confirmed by culture. The specificity of the test was 94%, making it suitable for use in laboratories without facilities for IFAT or ELISA. PMID:1401194

Kang, G; Sridharan, G; Jesudason, M V; John, T J

1992-08-01

74

Cleaning up of a nuclear facility: Destocking of Pu radioactive waste and nuclear Non-Destructive Assays  

NASA Astrophysics Data System (ADS)

In view to clean up a nuclear facility located at the CEA, Cadarache, France, three Non Destructive Assay (NDA) methods have been combined to characterize 2714 old, 100 L radioactive waste drums produced between 1980 and 1997. The results of X-ray radiography, passive neutron measurement and gamma-ray spectrometry are used together to extract both the ?? and ? activities, and the Pu mass contained in each drum. Those drums will then be re-conditioned and cemented in 870 L containers, in order to be sent to the adequate disposal or interim storage. This paper presents the principle of the three NDA methods, the dedicated measurement setups, and it gives details about the setups, which have been especially designed and developed for that application. Uncertainties are dealt with in the last part of the paper.

Jallu, F.; Allinei, P.-G.; Bernard, Ph.; Loridon, J.; Pouyat, D.; Torreblanca, L.

2012-07-01

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

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

77

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

78

Design and operation of a passive neutron monitor for assaying the TRU content of solid wastes  

SciTech Connect

A passive neutron monitor has been designed and built for determining the residual transuranic (TRU) and plutonium content of chopped leached fuel hulls and other solid wastes from spent Fast Flux Test Facility (FFTF) fuel. The system was designed to measure as little as 8 g of plutonium or 88 mg of TRU in a waste package as large as a 208-l drum which could be emitting up to 220,000 R/hr of gamma radiation. For practical purposes, maximum assay times were chosen to be 10,000 sec. The monitor consists of 96 /sup 10/BF/sub 3/ neutron sensitive proportional counting tubes each 5.08 cm in diameter and 183 cm in active length. Tables of neutron emission rates from both spontaneous fission and (..cap alpha..,n) reactions on oxygen are given for all contributing isotopes expected to be present in spent FFTF fuel. Tables of neutron yeilds from isotopic compositions predicted for various exposures and cooling times are also given. Methods of data reduction and sources, magnitude, and control of errors are discussed. Backgrounds and efficiencies have been measured and are reported. A section describing step-by-step operational procedures is included. Guidelines and procedures for quality control and troubleshooting are also given. 13 references, 15 figures, 4 tables.

Brodzinski, R.L.; Brown, D.P.; Rieck, H.G. Jr.; Rogers, L.A.

1984-02-01

79

Development of a polydimethylsiloxane film-based passive dosing method in the in vitro DR-CALUX® assay.  

PubMed

In bioassays, exposure concentrations of test compounds are usually expressed as nominal concentrations. As a result of various processes, such as adsorption, degradation, or uptake, the actual freely dissolved concentration of the test compound may differ from the nominal concentration. The goal of the present study was to develop a method to dose passively the freely dissolved fraction of organic chemicals in an in vitro bioassay with adherent cells. To this end, a polydimethylsiloxane (PDMS) film-based method was developed for a reporter gene assay for dioxin-like compounds in a rat liver cell line. Polydimethylsiloxane films loaded with test compounds ensure that the concentration during exposure is in equilibrium and that the ratio between the concentration on the film and the concentration in medium is constant. Benzo[k]fluoranthene (BkF) was used as a model compound to develop the passive dosing method in transwell plates, which was further tested with a complex mixture, i.e., an extract prepared from a contaminated sediment. A higher dioxin-like activity was found when extracts were dosed by passive dosing with PDMS than when directly added to medium. Comparison with analysis of the concentration of BkF in medium shows that passive dosing of individual chemicals may not be necessary if freely dissolved concentrations are known. Use of PDMS for passive dosing of complex samples may represent a more realistic method for exposure in in vitro bioassays. PMID:21191882

Booij, Petra; Lamoree, Marja H; Leonards, Pim E G; Cenijn, Peter H; Klamer, Hans J C; van Vliet, L Alexander; Akerman, Johan; Legler, Juliette

2011-04-01

80

In-plant measurements of gamma-ray transmissions for precise K-edge and passive assay of plutonium concentration and isotopic fractions in product solutions. Final report on TASTEX Task G  

SciTech Connect

An instrument based upon high-resolution gamma-ray measurements has been tested for more than 1 year at the Tokai Reprocessing Facility for determination of plutonium concentration by K-edge absorption densitometry and for determination of plutonium isotopic fractions by transmission-corrected passive gamma-ray spectrometry. The nondestructive assay instrument was designed and built at Los Alamos National Laboratory for the Tokai Advanced Safeguards Technology Exercise (TASTEX). It was used at Tokai for the timely assay of more than 100 product solution samples during the TASTEX evaluations. The results were compared to reference values obtained by conventional destructive analysis of these samples. The precision and accuracy of plutonium concentrations measured by the K-edge technique are shown to be within 0.6% (1delta) in these applications. The precisions and accuracies of the isotopic fractions determined by these passive gamma-ray methods are shown to be within 0.4% for /sup 239/Pu, 1% for /sup 240/Pu and /sup 241/Pu, and 10% for /sup 242/Pu.

Russo, P.A.; Hsue, S.T.; Sprinkle, J.K. Jr.; Johnson, S.S.; Asakura, Y.; Kondo, I.; Masui, J.; Shoji, K.

1982-08-01

81

Application of the PAN\\/GEA\\/AK method to the Non-Destructive Assay of Remote Handled TRU Waste  

Microsoft Academic Search

Combining Passive Active Neutron \\/ Gamma Energy Analysis with process or acceptable knowledge (the PAN\\/GEA\\/AK technique) has been successfully deployed for the characterization of contact handled (CH) transuranic (TRU) waste in accordance with the regulatory requirements. For most CH TRU streams Pu240 is the dominant source of spontaneous neutron emission, Pu239 is the dominant fissile isotope. Thus the signal from

A. P. Simpson; M. J. Clapham; P. A Clark; J. W. Rackham

82

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.

83

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

84

High sensitivity assay of cement encapsulated spent nuclear fuel sludge using the Imaging Passive Active Neutron (IPAN) system  

SciTech Connect

A new technique has been developed for high sensitivity assay of grouted spent nuclear fuel (SNF) sludge waste in 208 liter drums. The method uses the Imaging Passive Active Neutron (IPAN{sup TM}) system to provide regulatory acceptable measurements. At the Waste Receiving and Processing (WRAP) Facility in Hanford, two IPAN{sup TM} systems have been successfully calibrated and validated for assay of SNF grouted sludge drums (encapsulated with a cement mixture). The systems have been demonstrated to be capable of performing low level waste (LLW) / transuranic (TRU) waste sorting even in the presence of high gamma radiation fields emitted by the fission and activation products associated with SNF. The active and passive modes of the IPAN{sup TM} provide a wide dynamic range of assay: from below the TRU/LLW sorting threshold (100 nCi/g or 3700 Bq/g) up to several hundred grams of Weapons Grade Pu Equivalent. A new calibration technique was developed that uses a radial weighted average method to define the imaging response matrix. This method provides the required sensitivity to the height distribution of special nuclear material within the 208 liter drum, and makes use of the uniform radial distribution that will occur for a distribution of a large population of small particles in a homogeneous matrix. Extensive validation and testing with specially designed surrogate grouted sludge drums and radioactive standards have resulted in regulatory acceptance of this technique, permitting ultimate disposal of the SNF sludge drums at the Waste Isolation Pilot Plant. (authors)

Simpson, A.P. [BIL Solutions Inc, Santa Fe, NM (United States); Abdurrahman, N.M. [Fluor Hanford, Richland, WA (United States)

2007-07-01

85

Rapid Nondestructive Plutonium Isotopic Analysis.  

National Technical Information Service (NTIS)

Methods for plutonium isotopic measurements have been evaluated for nuclear safeguards inventory verification. A mobile, real-time, nondestructive assay, gamma-ray spectrometric measurement system has been assembled, moved and operated at several nuclear ...

J. E. Fager F. P. Brauer

1978-01-01

86

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.

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

2014-01-01

87

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

88

Nondestructive testing  

Microsoft Academic Search

In order to determine the effectiveness of a given nondestructive testing inspection procedure, trials must be conducted to compare predicted and actual defect sizes. Procedures based on magnetic particle inspection seem to be the most appropriate for detecting surface breaking cracks. Other procedures are required to measure crack depth. It will soon be possible for properly validated nondestructive testing equipment

1985-01-01

89

Non-destructive interrogation of uranium using PGAA  

NASA Astrophysics Data System (ADS)

Prompt gamma neutron activation analysis is proposed as an instant, non-destructive method for the assay of uranium and also for the determination of 235U-enrichment. Measurements were performed in the thermal and the cold neutron beams at the Budapest Research Reactor. A beam chopper was used to collect the delayed decay gamma radiation from short-lived nuclides separately. Partial gamma ray production cross-sections have been determined for a set of capture prompt, fission prompt and decay gamma lines and compared to those from the literature. The proposed method is also compared to NAA and the passive gamma spectroscopy of natural uranium.

Molnár, G. L.; Révay, Zs.; Belgya, T.

2004-01-01

90

Advances in passive neutron instruments for safeguards use  

Microsoft Academic Search

Passive neutron and other nondestructive assay techniques have been used extensively by the International Atomic Energy Agency to verify plutonium metal, powder, mixed oxide, pellets, rods, assemblies, scrap, and liquids. Normally, the coincidence counting rate is used to measure the ²⁴°Pu-effective mass and gamma-ray spectrometry or mass spectrometry is used to verify the plutonium isotopic ratios. During the past few

H. O. Menlove; M. S. Krick; D. G. Langner; M. C. Miller; J. E. Stewart

1994-01-01

91

Use of delayed gamma rays for active non-destructive assay of 235U irradiated by pulsed neutron source (plasma focus)  

NASA Astrophysics Data System (ADS)

A pulsed neutron source based on plasma focus device has been used for active interrogation and assay of 235U by monitoring its delayed high energy ?-rays. The method involves irradiation of fissile material by thermal neutrons obtained after moderation of a burst of neutrons emitted upon fusion of deuterium in plasma focus (PF) device. The delayed gamma rays emitted from the fissile material as a consequence of induced fission were detected by a large volume sodium iodide (NaI(Tl) detector. The detector is coupled to a data acquisition system of 2k input size with 2k ADC conversion gain. Counting was carried out in pulse height analysis mode for time integrated counts up to 100 s while the temporal profile of delayed gamma has been obtained by counting in multichannel scaling mode with dwell time of 50 ms. To avoid the effect of passive (natural) and active (from surrounding materials) backgrounds, counts have been acquired for gamma energy between 3 and 10 MeV. The lower limit of detection of 235U in the oxide samples with this set-up is estimated to be 14 mg.

Andola, Sanjay; Niranjan, Ram; Kaushik, T. C.; Rout, R. K.; Kumar, Ashwani; Paranjape, D. B.; Kumar, Pradeep; Tomar, B. S.; Ramakumar, K. L.; Gupta, S. C.

2014-07-01

92

Evaluation of enzyme-linked immunosorbent assay and reversed passive hemagglutination for detection of Crimean-Congo hemorrhagic fever virus antigen.  

PubMed Central

Enzyme-linked immunosorbent assay (ELISA) and a reversed passive hemagglutination (RPHA) test were evaluated for rapid detection of Crimean-Congo hemorrhagic fever (CCHF) virus antigens. Both RPHA and ELISA detected CCHF antigen in the brains of infant mice 2 to 3 days after infection, several days before the animals sickened and died. Antigen was also detected after 1 to 2 days in infected cell culture extracts and after 2 to 4 days in culture supernatant fluids. Both tests detected CCHF antigen at threshold values of approximately 2.5 log10 tissue culture infective doses per ml and were more sensitive than complement fixation, immunodiffusion, or immunofluorescence. In a comparative study on specimens from CCHF patients, virus was isolated from 38 of 49 sera and 23 of 28 patients. Antigen was detected in 20 of 49 sera (15 of 28 patients) by RPHA and in 29 of 49 sera (18 of 28 patients) by ELISA. Antigenemia was detected more frequently in fatal cases (9 of 11) than in nonfatal cases (9 of 17). Although the antigen detection assays offered a more rapid approach than infectivity assays for diagnosing CCHF, the latter test was more sensitive. The results suggest that RPHA and ELISA may be of use in rapid diagnosis of CCHF infection, particularly in severe cases, in which the danger of nosocomial spread is greatest.

Shepherd, A J; Swanepoel, R; Gill, D E

1988-01-01

93

Nondestructive evaluations  

NASA Astrophysics Data System (ADS)

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

94

Defining the needs for non-destructive assay of UF6 feed, product, and tails at gas centrifuge enrichment plants and possible next steps  

Microsoft Academic Search

Current safeguards approaches used by the IAEA at gas centrifuge enrichment plants (GCEPs) need enhancement in order to detect undeclared LEU production with adequate detection probability using non destructive assay (NDA) techniques. At present inspectors use attended systems, systems needing the presence of an inspector for operation, during inspections to verify the mass and ²³U enrichment of UF bulk material

Brian D Boyer; Martyn T Swinhoe; Bruce W Moran; Alain Lebrun

2009-01-01

95

Defining the needs for non-destructive assay of UF6 feed, product, and tails at gas centrifuge enrichment plants and possible next steps  

SciTech Connect

Current safeguards approaches used by the IAEA at gas centrifuge enrichment plants (GCEPs) need enhancement in order to detect undeclared LEU production with adequate detection probability using non destructive assay (NDA) techniques. At present inspectors use attended systems, systems needing the presence of an inspector for operation, during inspections to verify the mass and {sup 235}U enrichment of UF{sub 6} bulk material used in the process of enrichment at GCEPS. The inspectors also take destructive assay (DA) samples for analysis off-site which provide accurate, on the order of 0.1 % to 0.5% uncertainty, data on the enrichment of the UF{sub 6} feed, tails, and product. However, DA sample taking is a much more labor intensive and resource intensive exercise for the operator and inspector. Furthermore, the operator must ship the samples off-site to the IAEA laboratory which delays the timeliness of the results and contains the possibility of the loss of the continuity of knowledge of the samples during the storage and transit of the material. Use of the IAEA's inspection sampling algorithm shows that while total sample size is fixed by the total population of potential samples and its intrinsic qualities, the split of the samples into NDA or DA samples is determined by the uncertainties in the NDA measurements. Therefore, the larger the uncertainties in the NDA methods, more of the sample taken must be DA samples. Since the DA sampling is arduous and costly, improvements in NDA methods would reduce the number of DA samples needed. Furthermore, if methods of on-site analysis of the samples could be developed that have uncertainties in the 1-2% range, a lot of the problems inherent in DA sampling could be removed. The use of an unattended system that could give an overview of the entire process giving complementary data on the enrichment process as well as accurate measures of enrichment and weights of the UF{sub 6} feed, tails, and product would be a major step in enhancing the ability of NDA beyond present attended systems. The possibility of monitoring the feed, tails, and product header pipes in such a way as to gain safeguards relevant flow and enrichment information without compromising the intellectual property of the operator including proprietary equipment and operational parameters would be a huge step forward. This paper contains an analysis of possible improvements in unattended and attended NDA systems including such process monitoring and possible on-site analysis of DA samples that could reduce the uncertainty of the inspector measurements reducing the difference between the operator's and inspector's measurements providing more effective and efficient IAEA GeEPs safeguards.

Boyer, Brian D [Los Alamos National Laboratory; Swinhoe, Martyn T [Los Alamos National Laboratory; Moran, Bruce W [IAEA; Lebrun, Alain [IAEA

2009-01-01

96

A PAMPA assay as fast predictive model of passive human skin permeability of new synthesized corticosteroid C-21 esters.  

PubMed

The permeation properties of twenty newly synthesized ?-alkoxyalkanoyl and ?-aryloxyalkanoyl C-21 esters of standard corticosteroids: Fluocinolone acetonide, dexamethasone, triamcinolone acetonide and hydrocortisone were established using a PAMPA assay (70% silicone oil and 30% isopropyl myristate). The data were compared with parent corticosteroids with addition of mometasone furoate and hydrocortisone acetate. All newly synthesized corticosteroid C-21 esters have effective permeability coefficients higher then -6, mostly followed with high values of retention factors and low permeation. The examined compounds were grouped through relationship between obtained retention factors and permeation parameters (groups I-III). The classification confirmed group I (membrane retentions as well as permeation lower then 30%) for all corticosteroid standards except mometasone furoate, a potent topical corticosteroid which, with high membrane retention (81%) and low permeation (7.7%) fits into group III. The largest number of new synthesized corticosteroids C-21 esters, among them all fluocinolone acetonide C-21 esters, have high membrane retentions (32.4%-86.5%) and low permeations (1.3%-27.1%), fitting in group III. The classification was related to previously obtained anti-inflammatory activity data for the fluocinolone acetonide C-21 esters series. According to the PAMPA results the new synthesized esters could be considered as potential new prodrugs with useful benefit/risk ratio. PMID:22222907

Markovic, Bojan D; Vladimirov, Sote M; Cudina, Olivera A; Odovic, Jadranka V; Karljikovic-Rajic, Katarina D

2012-01-01

97

Non-destructive testing  

Microsoft Academic Search

This text covers, the underlying principles and some major applications of non-destructive inspection methods. Complete chapters are devoted to each of the following: liquid penetration inspection, magnetic particle inspection, electrical testing, ultrasonic testing and radiography. The concluding chapter introduces the reader to some of the more recent developments in non-destructive inspection.

B. Hull; V. John

1988-01-01

98

Advances in passive neutron instruments for safeguards use  

SciTech Connect

Passive neutron and other nondestructive assay techniques have been used extensively by the International Atomic Energy Agency to verify plutonium metal, powder, mixed oxide, pellets, rods, assemblies, scrap, and liquids. Normally, the coincidence counting rate is used to measure the {sup 240}Pu-effective mass and gamma-ray spectrometry or mass spectrometry is used to verify the plutonium isotopic ratios. During the past few years, the passive neutron detectors have been installed in plants and operated in the unattended/continuous mode. These radiation data with time continuity have made it possible to use the totals counting rate to monitor the movement of nuclear material. Monte Carlo computer codes have been used to optimize the detector designs for specific applications. The inventory sample counter (INVS-III) has been designed to have a higher efficiency (43%) and a larger uniform counting volume than the original INVS. Data analyses techniques have been developed, including the ``known alpha`` and ``known multiplication`` methods that depend on the sample. For scrap and other impure or poorly characterized samples, we have developed multiplicity counting, initially implemented in the plutonium scrap multiplicity counter. For large waste containers such as 200-L drums, we have developed the add-a-source technique to give accurate corrections for the waste-matrix materials. This paper summarizes recent developments in the design and application of passive neutron assay systems.

Menlove, H.O.; Krick, M.S.; Langner, D.G.; Miller, M.C.; Stewart, J.E.

1994-02-01

99

Recent advancement of electromagnetic nondestructive inspection technology in Japan  

Microsoft Academic Search

In this paper, the electromagnetic nondestructive testing (NDT) of present interest for research and industrial applications in Japan is described. Besides ac and pulsed eddy-current testing, magnetic flux leakage testing, passive magnetic flux leakage for characterization of material degradation, and various inversion techniques are presented. Both simulation and experimental results are used to demonstrate validity of the electromagnetic NDT methods

Kenzo Miya

2002-01-01

100

Active and passive mode calibration of the Combined Thermal Epithermal Neutron (CTEN) system  

SciTech Connect

The Combined Thermal/Epithermal Neutron (CTEN) non-destructive assay (NDA) system was designed to assay transuranic waste by employing an induced active neutron interrogation and/or a spontaneous passive neutron measurement. This is the second of two papers, and focuses on the passive mode, relating the net double neutron coincidence measurement to the plutonium mass via the calibration constant. National Institute of Standards and Technology (NIST) calibration standards were used and the results verified with NIST-traceable verification standards. Performance demonstration program (PDP) 'empty' 208-L matrix drum was used for the calibration. The experimentally derived calibration constant was found to be 0.0735 {+-} 0.0059 g {sup 240}Pu effective per unit response. Using this calibration constant, the Waste Isolation Pilot Plant (WIPP) criteria was satisfied with five minute waste assays in the range from 3 to 177g Pu. CTEN also participated in the PDP Cycle 8A blind assay with organic sludge and metal matrices and passed the criteria for accuracy and precision in both assay modes. The WIPP and EPA audit was completed March 1, 2002 and full certification is awaiting the closeout of one finding during the audit. With the successful closeout of the audit, the CTEN system will have shown that it can provide very fast assays (five minutes or less) of waste in the range from the minimum detection limit (about 2 mg Pu) to 177 g Pu.

Veilleux, J. M. (John M.)

2002-06-01

101

[Nondestructive Evaluation (NDE) Capabilities  

NASA Technical Reports Server (NTRS)

These poster boards display the United Space Alliance's (USA) systems and equipment used for Nondestructive Evaluation. These include: (1) the Robotic Inspection Facility, (2) CAT-Scan and Laminography, (3) Laser Surface Profilometry, (4) Remote Eddy Current, (5) Ultrasonic Phased Array, (7) Infrared Flash Thermography, and (8) Backscatter X-Ray (BSX)

Born, Martin

2010-01-01

102

Nondestructive testing methods  

Microsoft Academic Search

Nondestructive inspection (NDI) involves the interpretation of signals reflected from, in interaction with, or emitted from the object to be investigated. Visual inspection may be defined as an inspection where the inspector can observe the defect or its image directly. Nonvisual inspection may be defined as all inspections where the inspector cannot see the defect or its image directly, but

P. F. A. Bijlmer

1978-01-01

103

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

SciTech Connect

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

Schultz, F.J. (Oak Ridge National Lab., TN (United States)); Caldwell, J.T. (Pajarito Scientific Corp., Los Alamos, NM (United States))

1991-08-01

104

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

105

In-plant measurements of gamma-ray transmissions for precise K-edge and passive assay of plutonium concentration and isotopic abundance in product solutions at the Tokai Reprocessing Plant  

SciTech Connect

A field test has been carried out for more than 2 years for determination of plutonium concentration by K-edge absorption densitometry and for determination of plutonium isotopic abundance by transmission-corrected passive gamma-ray spectrometry. This system was designed and built at Los Alamos National Laboratory and installed at the Tokai reprocessing plant of the Power Reactor and Nuclear Fuel Development Corporation as a part of the Tokai Advanced Safeguards Technology Exercise (TASTEX). For K-edge measurement of plutonium concentration, the transmissions at two discrete gamma-ray energies are measured using the 121.1- and 122.1-keV gamma rays from /sup 75/Se and /sup 57/Co. Intensities of the plutonium passive gamma rays in the energy regions between 38 and 51 keV and between 129 and 153 keV are used for determination of the isotopic abundances. More than 200 product solution samples have been measured in a timely fashion during these 2 years. The relative precisions and accuracies of the plutonium concentration measurement are shown to be within 0.6% (1 sigma) in these applications, and those for plutonium isotopic abundances are within 3% for /sup 238/Pu, 0.4% for /sup 239/Pu, 1.2% for /sup 240/Pu, 1.3% for /sup 241/Pu, and 7% for /sup 242/Pu. The time required is 10 min for the concentration assay, 10 min for the isotopics assay, and about 15 min for handling procedures in the laboratory.

Asakura, Y.; Kondo, I.; Masui, J.; Shoji, K.; Russo, P.A.; Hsue, S.T.; Sprinkle, J.K. Jr.; Johnson, S.S.

1982-01-01

106

Nondestructive material characterization  

SciTech Connect

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

107

Passive exoskeleton  

US Patent & Trademark Office Database

The present invention relates to a load bearing apparatus, and more particularly, to a passive exoskeleton whereby a load may be placed on the passive exoskeleton and thereby transfer weight of the load from the passive exoskeleton to a ground surface. The passive exoskeleton comprises a rigid body member for attaching proximate a portion of a user's body, a sliding rod attached with the body member, and a ground surface engage-able foot analog attached with the sliding rod. When a user places a load on the body member, weight of the load from is transferred from the body member, through the sliding rod, and into the foot analog, causing the passive exoskeleton to support at least a portion of the load.

2009-08-11

108

/sup 125/I-Fibrin deposition in contact sensitivity reactions in the mouse. Sensitivity of the assay for quantitating reactions after active or passive sensitization  

SciTech Connect

The clotting associated with delayed hypersensitivity (DH) responses in the mouse by sensitizing the animals to the contactant oxazolone (Ox), and then administering /sup 125/I-guinea pig fibrinogen i.v. 10 to 30 min before antigen challenge 5 days later. Early (4 to 8 hr) contact sensitivity (CS) responses in immunized mice were barely detectable by three conventional measures of CS, but the total /sup 125/I-cpm in ears challenged with hapten was 3.6 to 4.5 x that in control ears challenged with vehicle alone; moreover, the amount of urea-insoluble cpm (cross-linked /sup 125/I-fibrin-associated cpm) in the reactions to Ox was 6.5-fold to 8.2-fold that present in the control reactions. In 24 hr reactions that were near peak intensity by measurements of ear swelling, ear weight ratios, and ratios of /sup 125/I-5-iodo-2-deoxyuridine-labeled leukocyte infiltration, the cpm in antigen-challenged ears exceeded that in control ears by 13-fold to 53-fold. In addition, antigen-challenged ears contained 27 to 300 x the urea-insoluble cpm present in control ears. /sup 125/I-Fibrin deposition was not a specific characteristic of CS reactions, because a small amount of urea-insoluble reactivity was also detected in some reactions to Ox in native mice. Nevertheless, the assay was exquisitely sensitive and readily detected quantitative differences between the immunologically specific and nonspecific reactions at very early intervals after challenge or with suboptimal doses of antigen.

Mekori, Y.A.; Dvorak, H.F.; Galli, S.J.

1986-03-15

109

Nondestructive evaluation technique guide  

NASA Technical Reports Server (NTRS)

A total of 70 individual nondestructive evaluation (NDE) techniques are described. Information is presented that permits ease of comparison of the merits and limitations of each technique with respect to various NDE problems. An NDE technique classification system is presented. It is based on the system that was adopted by the National Materials Advisory Board (NMAB). The classification system presented follows the NMAB system closely with the exception of additional categories that have been added to cover more advanced techniques presently in use. The rationale of the technique is explained. The format provides for a concise description of each technique, the physical principles involved, objectives of interrogation, example applications, limitations of each technique, a schematic illustration, and key reference material. Cross-index tabulations are also provided so that particular NDE problems can be referred to appropriate techniques.

Vary, A.

1973-01-01

110

Nondestructive characterization of low-level transuranic waste  

SciTech Connect

The use of nondestructive evaluation (NDE) methods is proposed for characterization of transuranic (TRU) waste stored at the Radioactive Waste Management Complex. These NDE methods include real-time x-ray radiography, real-time neutron radiography, x-ray and neutron computed tomography, thermal imaging, container weighing, visual examination, and acoustic measurements. An integrated NDE system is proposed for characterization and certification of TRU waste destined for eventual shipment to the Waste Isolation Pilot Plant in New Mexico. Methods for automating both the classification waste and control of a complete nondestructive evaluation/nondestructive assay system are presented. Feasibility testing of the different NDE methods, including real-time x-ray radiography, and development of automated waste classification techniques are covered as part of a five year effort designed to yield a production waste characterization system.

Barna, B.A.; Reinhardt, W.W.

1981-10-01

111

Passive euthanasia  

PubMed Central

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 arguments for the Task Force's view. Three arguments are considered. Firstly, an argument based on the (supposed) wrongness of euthanasia and the (supposed) permissibility of what is often called passive euthanasia. Secondly, the claim that passive euthanasia (so-called) cannot really be euthanasia because it does not cause death. And finally, a consequence based argument which appeals to the (alleged) bad consequences of accepting the category of passive euthanasia. We conclude that although healthcare professionals' nervousness about the concept of passive euthanasia is understandable, there is really no reason to abandon the category provided that it is properly and narrowly understand and provided that "euthanasia reasons" for withdrawing or withholding life-prolonging treatment are carefully distinguished from other reasons.

Garrard, E; Wilkinson, S

2005-01-01

112

Recent Improvements Concerning Nondestructive Testing.  

National Technical Information Service (NTIS)

Rare are the techniques of which development is not already touched by microelectronics and micro-data processing. Nondestructive testing and more particularly ultrasonic and Foucault current testing follow this general rule. With some examples, this pape...

M. Asty

1984-01-01

113

Simultaneous materials evaluation with both electronic shearography and infrared nondestructive evaluation  

Microsoft Academic Search

With the increasing use of advanced materials in the aerospace, automotive, and medical industries, improved nondestructive evaluation techniques are needed to meet industry requirements for quality and product reliability. Both shearography and infrared thermography are noncontact, single-sided inspection techniques that can provide quantitative information about a material's characteristics by means of passive or active excitation techniques. An experiment was conducted

Morteza Safai

1995-01-01

114

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

115

An Experimental Study of Defect Determination using Pulsed Thermal Non-Destructive Testing  

Microsoft Academic Search

The application of Infrared Thermography (IRT) as passive method is widely used and accepted by industry. However, IRT technology as transient or active method is considerably new for industry in term of measuring defect in Non-Destructive Testing (NDT) activities. The primary objective of this paper is to present an experimental study of determination of artificial defect in material using active

M. Z. Umar; I. Ahmad; A. R. Hamzah; W. S. W. Abdullah

2008-01-01

116

Nondestructive radioassay for waste management: an assessment  

SciTech Connect

Nondestructive Assay (NDA) for Transuranic Waste Management is used to mean determining the amount of transuranic (TRU) isotopes in crates, drums, boxes, cans, or other containers without having to open the container. It also means determining the amount of TRU in soil, bore holes, and other environmental testing areas without having to go through extensive laboratory wet chemistry analyses. it refers to radioassay techniques used to check for contamination on objects after decontamination and to determine amounts of TRU in waste processing streams without taking samples to a laboratory. Gednerally, NDA instrumentation in this context refers to all use of radioassay which does not involve taking samples and using wet chemistry techniques. NDA instruments have been used for waste assay at some sites for over 10 years and other sites are just beginning to consider assay of wastes. The instrumentation used at several sites is discussed in this report. Almost all these instruments in use today were developed for special nuclear materials safeguards purposes and assay TRU waste down to the 500 nCi/g range. The need for instruments to assay alpha particle emitters at 10 nCi/g or less has risen from the wish to distinguish between Low Level Waste (LLW) and TRU Waste at the defined interface of 10 nCi/g. Wastes have historically been handled as TRU wastes if they were just suspected to be transuranically contaminated but their exact status was unknown. Economic and political considerations make this practice undesirable since it is easier and less costly to handle LLW. This prompted waste generators to want better instrumentation and led the Transuranic Waste Management Program to develop and test instrumentation capable of assaying many types of waste at the 10 nCi/g level. These instruments are discussed.

Lehmkuhl, G.D.

1981-06-01

117

Passive Maser.  

National Technical Information Service (NTIS)

A passive maser wherein control of the cavity and control of the oscillator on the line of stimulated emission operate in a shared-time mode. A control circuit acts on the injected signal by way of a programmable synthesizer, the injected signal then assu...

A. H. Frank J. D. White

1981-01-01

118

Passive Accelerometer  

NASA Technical Reports Server (NTRS)

Motion of ball in liquid indicates acceleration. Passive accelerometer measures small accelerations along cylindrical axis. Principle of operation based on Stokes' law. Provides accurate measurements of small quasi-steady accelerations. Additional advantage, automatically integrates out unwanted higher-frequency components of acceleration.

Naumann, Robert J.; Baugher, Charles; Alexander, Iwan

1992-01-01

119

Operational and Regulatory Performance of Waste Crate Assay Systems at RFETS.  

National Technical Information Service (NTIS)

As Rocky Flats Environmental Technology Site (RFETS) approaches its closure target of 2006 emphasis for Non-Destructive Assay (NDA) has shifted from small waste package assay systems towards larger systems that are designed to accommodate Standard Waste B...

M. J. Clapham J. Franco A. Simpson J. Santo F. M. Durel H. O. Menlove

2003-01-01

120

Simultaneous materials evaluation with both electronic shearography and infrared nondestructive evaluation  

NASA Astrophysics Data System (ADS)

With the increasing use of advanced materials in the aerospace, automotive, and medical industries, improved nondestructive evaluation techniques are needed to meet industry requirements for quality and product reliability. Both shearography and infrared thermography are noncontact, single-sided inspection techniques that can provide quantitative information about a material's characteristics by means of passive or active excitation techniques. An experiment was conducted using a focal plane array infrared camera and a traditional Michelson's shearing interferometric system. In this paper, the results of the experiment are discussed, and the advantages of using both shearography and thermography simultaneously for materials evaluation and nondestructive testing are presented.

Safai, Morteza

1995-01-01

121

Nondestructive examination through painted surfaces  

Microsoft Academic Search

This study was performed to develop reliable nondestructive examination techniques for detecting cracks or other surface-open defects through a surface coating on ferromagnetic materials, and to provide a basis for recommending Section XI Code changes. The recommendations from this study led to the publication of ASME Code Cases for magnetic particle and eddy current methods that provide for qualification of

J. A. Holm; J. F. Cook; Soung-Nan Liu

1991-01-01

122

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% (1sigma) 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. 4 figs., 1 tab.

Menlove, H.O.; Stewart, J.E.

1985-02-04

123

Nondestructive Spent Fuel Assay Using Nuclear Resonance Fluorescence  

Microsoft Academic Search

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

Brian Quiter; Bernhard Ludewigt; Vladimir Mozin; Steven Tobin

2009-01-01

124

Mobile Nondestructive Assay (NDA) Measurements of Standard Waste Boxes (SWB)  

SciTech Connect

A mobile NDA system was composed and qualified for Safeguards measurements of multiple standard waste boxes (SWB) generated as a result of clean-out activities at Hanford’s Plutonium Finishing Plant (PFP). The system included a neutron slab counter and high purity germanium (HPGe) detector. PC/FRAM software was used to determine the isotopic composition of plutonium residue contained in the waste in order to interpret two independent measurement results provided by total neutron counting and gamma energy analysis (GEA). The measurement procedure developed to estimate transuranic (TRU) content of boxes was based on assumptions about characteristics of the matrix and material distribution. The neutron slab counter was calibrated with various plutonium working standards that were placed in a surrogate SWB specifically made to simulate miscellaneous waste debris. Transmission measurements with a californium source were used to correct for the matrix effects. An In-Situ Object Counting System (ISOCS) was used to acquire spectra from SWBs and ISOCS software was applied to generate the efficiency curve of the HPGe detector. Infinite energy extrapolation was introduced to correct GEA results for self-attenuation. The gamma and neutron results obtained on multiple SWBs are compared and discussed in the paper. Revised measurement positions for the detector and the transmission source are also suggested based on experience gained during the measurements.

Mozhayev, Andrey V.; Berg, Randal K.; Haggard, Daniel L.; Hilliard, James R.; Mapili, Gabriel M.

2006-11-01

125

Assessing Measurement Control: Experiences with Nondestructive Assay Methods.  

National Technical Information Service (NTIS)

Demonstration of stability or control of a measurement process over time is often required for critical processes. Measurement control is monitored by calculating measurement errors for a collection of comparison standards over time and producing a Shewha...

J. Glosup

1997-01-01

126

Assessing measurement control: experiences with nondestructive assay methods  

Microsoft Academic Search

Demonstration of stability or control of a measurement process over time is often required for critical processes. Measurement control is monitored by calculating measurement errors for a collection of comparison standards over time and producing a Shewhart control chart. However, measurement errors inherently occur one-at-a-time and not in batches. Additionally there is often a non-deterministic drift in the mean measurement

Glosup

1997-01-01

127

Making transuranic assay measurements using modern controllers  

SciTech Connect

This paper describes methodology and computer-controlled instrumentation developed at the Los Alamos National Laboratory that accurately performs nondestructive assays of large containers bearing transuranic wastes and nonradioactive matrix materials. These assay systems can measure fissile isotopes with 1-mg sensitivity and spontaneous neutron-emitting isotopes at a 10-mg sensitivity. The assays are performed by neutron interrogation, detection, and counting in a custom assay chamber. An International Business Machines Personal Computer (IBM-PC) is used to control the CAMAC-based instrumentation system that acquires the assay data. 6 refs., 7 figs.

Kuckertz, T.H.; Caldwell, J.T.; Medvick, P.A.; Kunz, W.E.; Hastings, R.D.

1987-01-01

128

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

129

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

130

Reflection shearography for nondestructive evaluation  

NASA Astrophysics Data System (ADS)

Conventional nondestructive evaluation (NDE) techniques include visual inspection, eddy current scanning, ultrasonics, and fluorescent dye penetration. These techniques are limited to local evaluation, often miss small buried defects, and are useful only on polished surfaces. Advanced NDE techniques include laser ultrasonics, holographic interferometry, structural integrity monitoring, shearography, and thermography. A variation of shearography, employing reflective shearographic interferometry, has been developed. This new shearographic interferometer is discussed, together with models to optimize its performance and experiments demonstrating its use in NDE.

Kurtz, Russell M.; Piliavin, Michael A.; Pradhan, Ranjit D.; Aye, Tin M.; Savant, Gajendra D.; Jannson, Tomasz P.; Hergert, Steffen

2004-09-01

131

Magnetoresistive Sensors for Nondestructive Evaluation  

Microsoft Academic Search

New high-sensitivity solid-state magnetoresistive (MR) sensor technologies offer significant advantages in nondestructive evaluation (NDE) systems. A key advantage of MR sensors is a flat frequency response extending from dc to hundreds of MHz, making them particularly attractive for low-frequency and multi- frequency eddy current detection for deep-flaw detection and depth profiling. MR sensors are mass produced by thin film processing

Albrecht Jander; Carl Smith; Robert Schneider

132

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

133

Forestall failures by nondestructive testing  

SciTech Connect

Nondestructive examination to spot defects is being increasingly applied to ensure the continued integrity of process equipment. This is particularly true in the chemical process industries (CPI) where the catastrophic failure of a component may endanger plant personnel, result in undesirable environmental consequences and cause costly business interruptions. To eliminate such failures, there are numerous codes and standards governing the fabrication, inspection and erection of pressure vessels and piping systems. The various codes cover a wide range of CPI equipment, including fired and unfired pressure vessels, heat exchangers, pipes, boilers, reformers, and compressors and other rotating machinery operating under a variety of service conditions. Operating conditions may result in service-related deterioration, such as corrosion, erosion, or cracking or embrittlement (such as from thermal or mechanical fatigue, or shocks). These types of deterioration can generally be detected by nondestructive examination before they reach a dangerous level. For best results, however, the nondestructive examination techniques must be carefully selected and properly applied, and the results of the tests interpreted in a meaningful manner. Several real-world examples of how to choose the right test methods, and of the best ways to interpret the results are given in this article. These case histories include ones where the right methods and interpretations saved millions of dollars in repair and shutdown costs.

Thielsch, H.; Cone, F.M. (Thielsch Engineering, Inc., Cranston, RI (United States))

1994-11-01

134

Nondestructive and continuous spectrophotometric measurement of cell respiration using a tetrazolium-formazan microemulsion  

Microsoft Academic Search

Triton X-100 was incorporated into a tetrazolium dye reduction assay using 3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT). Triton X-100 combines with the insoluble formazan product to form a homogeneous dispersion, or microemulsion, which allows reliable spectrophotometric measurement. The combination of this nonionic detergent and dye allows respiration to be measured nondestructively and thus continuously. The assay combines MTT with phenazine methosulfate, the appropriate

Raymond P Stowe; David W Koenig; S. K Mishra; Duane L Pierson

1995-01-01

135

Hood River Passive House.  

National Technical Information Service (NTIS)

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 a...

D. Hales

2013-01-01

136

Low-Level Waste Drum Assay Intercomparison Study  

Microsoft Academic Search

Nuclear waste assay is an integral element of programs such as safeguards, waste management, and waste disposal. The majority of nuclear waste is packaged in drums and analyzed by various nondestructive assay (NDA) techniques to identify and quantify the radioactive content. Due to various regulations and the public interest in nuclear issues, the analytical results are required to be of

K. Greutzmacher; J. Kuzminski; S. C. Myers

2003-01-01

137

Passive solar technology  

SciTech Connect

The present status of passive solar technology is summarized, including passive solar heating, cooling and daylighting. The key roles of the passive solar system designer and of innovation in the building industry are described. After definitions of passive design and a summary of passive design principles are given, performance and costs of passive solar technology are discussed. Passive energy design concepts or methods are then considered in the context of the overall process by which building decisions are made to achieve the integration of new techniques into conventional design. (LEW).

Watson, D

1981-04-01

138

Educational ultrasound nondestructive testing laboratory.  

PubMed

The ultrasound nondestructive evaluation (NDE) of materials course was developed for applied engineering technology students at Drexel University's Goodwin College of Professional Studies. This three-credit, hands-on laboratory course consists of two parts: the first part with an emphasis on the foundations of NDE, and the second part during which ultrasound NDE techniques are utilized in the evaluation of parts and materials. NDE applications are presented and applied through real-life problems, including calibration and use of the latest ultrasonic testing instrumentation. The students learn engineering and physical principles of measurements of sound velocity in different materials, attenuation coefficients, material thickness, and location and dimensions of discontinuities in various materials, such as holes, cracks, and flaws. The work in the laboratory enhances the fundamentals taught during classroom sessions. This course will ultimately result in improvements in the educational process ["The greater expectations," national panel report, http://www.greaterexpectations.org (last viewed February, 2008); R. M. Felder and R. Brent "The intellectual development of Science and Engineering Students. Part 2: Teaching to promote growth," J. Eng. Educ. 93, 279-291 (2004)] since industry is becoming increasingly reliant on the effective application of NDE technology and the demand on NDE specialists is increasing. NDE curriculum was designed to fulfill levels I and II NDE in theory and training requirements, according to American Society for Nondestructive Testing, OH, Recommended Practice No. SNT-TC-1A (2006). PMID:19045633

Genis, Vladimir; Zagorski, Michael

2008-09-01

139

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

140

Time-Spectral Analysis Methods for Spent Fuel Assay Using Lead SlowingDown Spectroscopy  

Microsoft Academic Search

Nondestructive techniques for measuring the mass of fissile isotopes in spent nuclear fuel is a considerable challenge in the safeguarding of nuclear fuel cycles. A nondestructive assay technology that could provide direct measurement of fissile mass, particularly for the plutonium (Pu) isotopes, and improve upon the uncertainty of today's confirmatory methods is needed. Lead slowing-down spectroscopy (LSDS) has been studied

Leon E. Smith; Kevin K. Anderson; Jennifer J. Ressler; Mark W. Shaver

2010-01-01

141

Nondestructive characterization of micromachined ceramics  

NASA Astrophysics Data System (ADS)

The aerospace, automotive, and electronic industries are finding increasing need for components made from silicon carbide (SiC) and silicon nitride (Si3N4). The development and use of miniaturized ceramic parts, in particular, is of significant interest in a variety of critical applications. As these application areas grow, manufacturers are being asked to find new and better solutions for machining and forming ceramic materials with microscopic precision. Recent advances in laser machining technologies are making precision micromachining of ceramics a reality. Questions regarding micromachining accuracy, residual melt region effects, and laser-induced microcracking are of critical concern during the machining process. In this activity, a variety of nondestructive inspection methods have been used to investigate the microscopic features of laser-machined ceramic components. The primary goal was to assess the micromachined areas for machining accuracy and microcracking using laser ultrasound, scanning electron microscopy, and white-light interference microscopic imaging of the machined regions.

Cooney, Adam; Hix, Kenneth E.; Yaney, Perry; Zhan, Qiwen; Dosser, Larry R.; Blackshire, James L.

2005-05-01

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

Non-Destructive Testing Scanner  

NASA Technical Reports Server (NTRS)

Bio-Imaging Research's technology that originated in an aerospace program has come full circle with a new aerospace adaptation called the Advanced Computed Tomography Inspection System, or ACTIS. The medical version of CT scans the human body for tumors or other abnormalities, the ACTIS system finds imperfections in aerospace structures and components, such as castings, assemblies, rocket motors and nozzles. ACTIS is described by its developer as the most versatile CT scanner available for non-destructive testing applications. ACTIS is a variable geometry system. ACTIS source and detectors can be moved closer together or farther apart to optimize the geometry for different sizes of test objects. The combination of variable geometry, three sources, and focusing detectors makes ACTIS cost effective for a broad range of applications. System can scan anything from very small turbine blades to large rocket assemblies.

1990-01-01

144

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

145

Nondestructive evaluation of structural ceramics  

NASA Technical Reports Server (NTRS)

Research on nondestructive evaluation (NDE) of structural ceramics for heat engine applications is reviewed. Microfocus radiography and scanning laser acoustic microscopy are the NDE techniques highlighted. The techniques were applied to research samples of sintered silicon nitride and silicon carbide in the form of modulus-of-rupture (MOR) bars. The strength and limitations of the aforementioned techniques are given in terms of probablility of detection for voids in green and sintered MOR bars. Voids for this purpose were introduced by seeding green ceramic bars and characterizing each void in terms of its size, shape, location, and nature before and after sintering. The effects of material density, microstructure, surface finish, thickness, void depth, and size characteristics on detectability are summarized.

Vary, Alex

1986-01-01

146

Photorefractive nondestructive memory with Kitty-type conjugator  

Microsoft Academic Search

In this report, we propose a photorefractive (PR) nondestructive memory with a Kitty-type phase conjugate mirror (Kitty PCM). Nondestructive readout without any fixing technique and high quality image rewriting can be achieved in this memory. An optical feedback circuit including a Kitty PCM is added on to the usual PR memory in the nondestructive reading method. The nondestructive readout means

Hisatoshi Funakoshi; Atsushi Okamoto

2003-01-01

147

Improved Ultrasonic Spectroscope for Nondestructive Inspection.  

National Technical Information Service (NTIS)

Improved instrumentation for ultrasonic spectroscopy was developed for the purpose of advanced nondestructive inspection of artillery projectiles. The equipment employs high-gain amplifiers to enable the reception and spectral processing of ultrasonic ech...

O. R. Gericke

1971-01-01

148

Emerging nondestructive inspection methods for aging aircraft.  

National Technical Information Service (NTIS)

This report identifies and describes emerging nondestructive inspection (NDI) methods that can potentially be used to inspect commercial transport and commuter aircraft for structural damage. The nine categories of emerging NDI techniques are: acoustic em...

A. Beattie L. Dahlke J. Gieske

1994-01-01

149

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...

150

29 CFR 1919.78 - Nondestructive examinations.  

Code of Federal Regulations, 2013 CFR

...and advisable to avoid disassembly of equipment, removal of pins, etc., examination of structure or parts by electronic, ultrasonic, or other nondestructive methods may be carried out, provided that the procedure followed is acceptable to the Assistant...

2013-07-01

151

Nonlethal and Nondestructive Combat in Cities Overseas.  

National Technical Information Service (NTIS)

The report examines nonlethal and nondestructive weapons--both present and potential--for their applicability to military operations in cities overseas. Classes of criteria for evaluation are suggested, and the suitability of various weapons concepts for ...

J. F. Coates

1970-01-01

152

Automation for Nondestructive Inspection of Aircraft.  

National Technical Information Service (NTIS)

We discuss the motivation and an architectural framework for using small mobile robots as automated aids to operators of nondestructive inspection (NDI) equipment. We review the need for aircraft skin inspection, and identify the constraints in commercial...

M. W. Siegel

1994-01-01

153

Holography: The Nondestructive Testing of Composite Structures.  

National Technical Information Service (NTIS)

Industrial applications of holography are discussed. The principle of nondestructive testing by laser holographic interferometry, and the parts to be tested (parts of motor case in composite materials) are described. The test facility, which involves a co...

P. Barbier C. Lefloch

1986-01-01

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

Electromagnetic Imaging Methods for Nondestructive Evaluation Applications  

PubMed Central

Electromagnetic nondestructive tests are important and widely used within the field of nondestructive evaluation (NDE). The recent advances in sensing technology, hardware and software development dedicated to imaging and image processing, and material sciences have greatly expanded the application fields, sophisticated the systems design and made the potential of electromagnetic NDE imaging seemingly unlimited. This review provides a comprehensive summary of research works on electromagnetic imaging methods for NDE applications, followed by the summary and discussions on future directions.

Deng, Yiming; Liu, Xin

2011-01-01

156

SWEPP Assay System Version 2.0 software design description  

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 radioactive waste containers. Containers of waste from Rocky Flats Environmental Technology Site and other Department of Energy (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. This program has been in operation since 1985 at the INEL Radioactive Waste Management Complex (RWMC). 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 originally used to perform the data acquisition and reduction functions for the neutron measurements. This program was originally developed at Los Alamos and extensively modified by a commercial vendor of PAN systems and by personnel at the INEL. NEUT2 uses the analysis methodology outlined, but no formal documentation exists on the program itself. The SWEPP Assay System (SAS) computer program replaced the NEUT2 program in early 1994. The SAS software was developed using an `object model` approach and is documented in accordance with American National Standards Institute (ANSI) and Institute of Electrical and Electronic Engineers (IEEE) standards. The new program incorporates the basic analysis algorithms found in NEUT2. Additional functionality and improvements include a graphical user interface, the ability to change analysis parameters without program code modification, an `object model` design approach and other features for improved flexibility and maintainability.

East, L.V.; Marwil, E.S.

1996-08-01

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

An Experimental Study of Defect Determination using Pulsed Thermal Non-Destructive Testing  

NASA Astrophysics Data System (ADS)

The application of Infrared Thermography (IRT) as passive method is widely used and accepted by industry. However, IRT technology as transient or active method is considerably new for industry in term of measuring defect in Non-Destructive Testing (NDT) activities. The primary objective of this paper is to present an experimental study of determination of artificial defect in material using active thermography, in particular to pulsed thermal NDT (TNDT). Both terminology and basic principles in TNDT will be discussed. It is shown that several factors may influences TNDT results. As a conclusion, this study has confirmed the ability and potential of TNDT as a technique for defect determination in material.

Umar, M. Z.; Ahmad, I.; Hamzah, A. R.; Abdullah, W. S. W.

2008-05-01

159

Summary of nondestructive testing theory and practice  

NASA Technical Reports Server (NTRS)

The ability to fabricate design critical and man-rated aerospace structures using materials near the limits of their capabilities requires a comprehensive and dependable assurance program. The quality assurance program must rely heavily on nondestructive testing methods for thorough inspection to assess properties and quality of hardware items. A survey of nondestructive testing methods is presented to provide space program managers, supervisors and engineers who are unfamiliar with this technical area with appropriate insight into the commonly accepted nondestructive testing methods available, their interrelationships, used, advantages and limitations. Primary emphasis is placed on the most common methods: liquid penetrant, magnetic particle, radiography, ultrasonics and eddy current. A number of the newer test techniques including thermal, acoustic emission, holography, microwaves, eddy-sonic and exo-electron emission, which are beginning to be used in applications of interest to NASA, are also discussed briefly.

Meister, R. P.; Randall, M. D.; Mitchell, D. K.; Williams, L. P.; Pattee, H. E.

1972-01-01

160

Advancing technologies and applications in nondestructive evaluation  

SciTech Connect

The methods used to inspect and evaluate materials, decides, and products are now based on imaging systems that collect digital data and process and interpret them through specially developed computer algorithms. Lawrence Livermore`s Nondestructive and Materials Evaluation Section has been developing a wide range of imaging systems, implementing them through a range of technologies, including digital radiography, computed tomography, machine vision, ultrasonics, and infrared computer thermography. Applications of these various technologies are described in the article. They demonstrate the range and increasing flexibility of the concept of nondestructive evaluation.

Logan, C.

1997-12-01

161

Nondestructive Evaluation (nde) of Damaged Structural Ceramics  

NASA Astrophysics Data System (ADS)

A combination of destructive and nondestructive testing methods was utilized to evaluate the impact velocity and energy conditions that caused fracture in alumina structural ceramics. Drop tower testing was used for low velocity impact with a high mass indenter and fragment simulating projectile testing was used for high velocity impact with a low mass projectile. The damaged samples were nondestructively evaluated using digital radiography and ultrasound C-scan imaging. The bulk damage detected by these techniques was compared to surface damage observed by visual inspection.

Brennan, R. E.; Green, W. H.; Sands, J. M.; Yu, J. H.

2009-03-01

162

A passive chevron replicator  

NASA Technical Reports Server (NTRS)

Instrument design provides replicate function between device storage area and guardrail detector in order that nondestructive read-out of memory can be achieved. Use of guardrail detectors in magnetic domain (bubble) circuits is proposed method of increasing detector signal output by increasing detector size without dedicating an excessive amount of device chip area to detector portion.

Oeffinger, T. R.; Tocci, L. R.

1977-01-01

163

International passive architectural survey  

SciTech Connect

An international survey of research, development, and demonstration in the passive solar design field was begun in October 1979 by the Solar Energy Reseach Institute's Passive Technology Program, and was completed in September 1980. Results will be available in late fall 1980.

Holtz, M. (Solar Energy Reseach Inst., Golden, CO); Diachok, D.; Shanks, D.

1980-01-01

164

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) [Walnut Creek, CA

2011-01-25

165

Passive solar building design  

SciTech Connect

This book presents the basic principles of passive solar design and offers quantitative design aids in the form of microcomputer programs to stimulate innovative passive designs. These programs are unlike most others, which focus on conventional designs. The volume also covers landscaping, energy conservation and aesthetics.

Carter, C.; De Villiers, J.

1987-01-01

166

Passive Solar Design  

NSDL National Science Digital Library

Students are introduced to passive solar design for buildings â an approach that uses the sun's energy and the surrounding climate to provide natural heating and cooling. They learn about some of the disadvantages of conventional heating and cooling and how engineers incorporate passive solar designs into our buildings for improved efficiency.

Integrated Teaching And Learning Program

167

Uncertainty analysis of the SWEPP PAN assay system for glass waste (content codes 440, 441 and 442)  

SciTech Connect

INEL is being used as a temporary storage facility for transuranic waste generated by the Nuclear Weapons program at the Rocky Flats Plant. Currently, there is a large effort in progress to prepare to ship this waste to WIPP. 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 Action Neutron (PAN) radioassay system. This paper discusses a modified statistical sampling and verification approach used to determine the total uncertainty of SWEPP PAN measurements for glass waste (content codes 440, 441, and 442) contained in 208 liter drums. In the modified statistical sampling and verification approach, the total performance of the SWEPP PAN nondestructive assay system for specifically selected waste conditions is simulated using computer models. A set of 100 cases covering the known conditions exhibited in glass waste was compiled using a combined statistical sampling and factorial experimental design approach. Parameter values assigned in each simulation were derived from reviews of approximately 100 real-time radiography video tapes of RFP glass waste drums, results from previous SWEPP PAN measurements on glass waste drums, and shipping data from RFP where the glass waste was generated. The data in the 100 selected cases form the multi-parameter input to the simulation model. The reported plutonium masses from the simulation model are compared with corresponding input masses. From these comparisons, the bias and total uncertainty associated with SWEPP PAN measurements on glass waste drums are estimated. The validity of the simulation approach is verified by comparing simulated output against results from calibration measurements using known plutonium sources and two glass waste calibration drums.

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

1996-10-01

168

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

169

Emerging nondestructive inspection methods for aging aircraft  

Microsoft Academic Search

This report identifies and describes emerging nondestructive inspection (NDI) methods that can potentially be used to inspect commercial transport and commuter aircraft for structural damage. The nine categories of emerging NDI techniques are: acoustic emission, x-ray computed tomography, backscatter radiation, reverse geometry x-ray, advanced electromagnetics, including magnetooptic imaging and advanced eddy current techniques, coherent optics, advanced ultrasonics, advanced visual, and

A. Beattie; L. Dahlke; J. Gieske

1994-01-01

170

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

171

Applications of Statistical Methods to Nondestructive Evaluation  

Microsoft Academic Search

Nondestructive evaluation (NDE) techniques are used widely in many manufacturing and operational areas of industry. NDE is a highly statistical science that has developed rapidly over the past decade with relatively little input from individuals with forma1 training in statistics. This review article describes some of the many methods and applications of NDE, including eddy-current methods for detecting fatigue in

Bryan D. Olin; William Q. Meeker

1996-01-01

172

Method for non-destructive testing  

SciTech Connect

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

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

Non-Destructive Evaluation of Aerospace Composites.  

National Technical Information Service (NTIS)

Five methods of non-destructive material evaluation (NDE) were used to inspect various forms of damage commonly found in aerospace fiberglass composites: voids, edge and sub-surface delaminations, surface burning, and cracking. The images produced by X-ra...

J. D. Johnson

2009-01-01

175

REVIEW ARTICLE: SQUIDs for nondestructive evaluation  

Microsoft Academic Search

We attempt a comprehensive review of all published research in nondestructive evaluation (NDE) performed with the superconducting quantum interference device (SQUID) magnetometer since the first work was reported in the mid-1980s. The SQUID is the most sensitive detector of magnetic flux known. The energy sensitivity of the SQUID may make it the most sensitive detector of any kind. The research

W. G. Jenks; S. S. H. Sadeghi; J. P. Wikswo Jr.

1997-01-01

176

Non-destructive XRF analysis of paintings  

Microsoft Academic Search

The preservation and conservation of our cultural heritage has become one of the main concerns today all over the world. In particular there is an increasing need for non-destructive investigations, as sampling from the unique and precious objects of art and archaeology. In addition to the conventional analytical procedures, techniques utilising nuclear instruments and methods play increasing role in this

Z. Szökefalvi-Nagy; I. Demeter; A. Kocsonya; I. Kovács

2004-01-01

177

Microwave Interferometer for Non-Destructive Testing  

NASA Astrophysics Data System (ADS)

A K-band microwave interferometer for non-destructive sensing of high frequency low amplitude (nm) vibration is demonstrated. This sensor uses direct-conversion receiver architecture with a phase shifter to adjust its sensitivity while varying the target distance. Detection of nanoscale vibration and laser-generated ultrasound waves through thin aluminum plate are measured and then compared with the theoretical results.

Choi, J.; Breugnot, S.; Itoh, T.

2010-02-01

178

Thermographic nondestructive evaluation: overview of recent progress  

Microsoft Academic Search

This paper presents a summary of recent research activities carried out at our laboratory in the field of Infrared Thermography for Nondestructive Evaluation (TNDE). First, we explore the latest developments in signal improvement. We describe three approaches: multiple pulse stimulation; the use of Synthetic Data for de-noising of the signal; and a new approach derived from the Fourier diffusion equation

Clemente Ibarra-Castanedo; Francois Galmiche; Akbar Darabi; Mariacristina Pilla; Matthieu Klein; Adel Ziadi; Steve Vallerand; Jean-François Pelletier; Xavier P. Maldague

2003-01-01

179

Holographic nondestructive testing in bone biomechanics  

NASA Astrophysics Data System (ADS)

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.

Silvennoinen, Raimo; Nygren, Kaarlo; Paatsama, Juha; Kaernae, Markku

180

Novel Trends in Optical Non-Destructive Testing Methods  

NASA Astrophysics Data System (ADS)

Non-destructive testing (NDT) describes a wide range of methods for measuring and comparing physical quantities against a nominal condition. In this paper we describe and compare different optical NdT (ONDT)-methods with respect to their characteristics and capability for different measurement tasks. ONDT may be specified in two categories, passive and active. The NDT principles of the first category just use a measurement method like view inspection, elipsometry or reflectometry to detect defects which are easily accessible. The principles of the second category use an excitation force, such as heat or mechanical vibration introduced by transducers to detect hidden defects. This category can be specified into two subcategories. The first subcategory "time-/depth-resolved" includes measurement methods delivering detailed information of the geometric features of a hidden defect. Therefore the excitation of the material and the detection of the reaction have to provide a ti! me step which enables depth-solved measurements. Phase-resolved thermography and laser ultrasound are examples for this category. The second subcategory "Integrating" includes measurement technique coupled with an excitation that enables detection of defects but not evaluation of their geometric features. Examples for these measurement techniques are shearography, reflectometry, vibrometry and thermography coupled with excitation method like simple heating or loading with a constant force. We demonstrate experimental results obtained using methods developed in our institute and highlight directions of further development.

Huke, P.; Klattenhoff, R.; von Kopylow, C.; Bergmann, R. B.

2013-07-01

181

ACR-1000 Passive Features  

SciTech Connect

The Advanced CANDU Reactor{sup TM} (ACR{sup TM}) is a Generation III+ pressure tube type reactor using light water coolant and heavy water moderator. The ACR-1000 reactor design is an evolutionary extension of the proven CANDU reactor design. The ACR-1000 incorporates multiple and diverse passive systems for accident mitigation. Where necessary, one or more features that are passive in nature have been included for mitigation of any postulated accident event. This paper describes how the use of passive design elements complements active features enhances reliability and improves safety margins. (authors)

Lekakh, Boris; Hau, Ken; Ford, Steven [Atomic Energy of Canada Ltd. (Canada)

2006-07-01

182

Neutron fluence rate measurements in a PGNAA 208-liter drum assay system using silicon carbide detectors  

Microsoft Academic Search

Pulsed prompt gamma neutron activation analysis (PGNAA) is being implemented for the nondestructive assay (NDA) of mercury, cadmium and lead in containers of radioactive waste. A PGNAA prototype system capable of assaying 208-liter (55-gallon) drums has already been built and demonstrated. As part of the evaluation of this system, the thermal neutron fluence rate distribution in a drum containing a

A. R. Dulloo; F. H. Ruddy; J. G. Seidel; S. Lee; B. Petrovi?; M. E. McIlwain

2004-01-01

183

Passive Explosion Barrier.  

National Technical Information Service (NTIS)

The patent application relates generally to explosion barriers for mines, or the like, and more particularly to a passive explosion barrier that is responsive to relatively low velocity, as well as intermediate and high velocity explosion generated wind, ...

Liebman Corry

1975-01-01

184

Passive MIMO Radar Detection.  

National Technical Information Service (NTIS)

Passive multiple-input multiple-output (MIMO) radar is a sensor network comprised of multiple distributed receivers that detects and localizes targets using the emissions from multiple non-cooperative radio frequency transmitters. This dissertation advanc...

D. E. Hack

2013-01-01

185

Passive-Solar Greenhouse.  

National Technical Information Service (NTIS)

Our project objective was to design, construct, and operate a commercialized (16' x 50') passive, solar greenhouse. The structure was originally intended as a vegetable forcing facility to produce vegetable crops in the off-season. Building and size const...

1982-01-01

186

Hexosaminidase assays.  

PubMed

beta-Hexosaminidases (EC 3.2.1.52) are lysosomal enzymes that remove terminal beta-glycosidically bound N-acetylglucosamine and N-acetylgalactosamine residues from a number of glycoconjugates. Reliable assay systems are particularly important for the diagnosis of a family of lysosomal storage disorders, the GM2 gangliosidoses that result from inherited beta-hexosaminidase deficiency. More recently, aberrant hexosaminidase levels have also been found to be associated with a variety of inflammatory diseases. Apart from patient testing and carrier screening, practical in vitro assays are indispensable for the characterization of knock-out mice with potentially altered hexosaminidase activities, for detailed structure-function studies aimed at elucidating the enzymatic mechanism, and to characterize newly described enzyme variants from other organisms. The purpose of this article is to discuss convenient hexosaminidase assay procedures for these and other applications, using fluorogenic or chromogenic artificial substrates as well as the physiological glycolipid substrate GM2. Attempts are also made to provide an overview of less commonly used alternative techniques and to introduce recent developments enabling high-throughput screening for enzyme inhibitors. PMID:18473163

Wendeler, Michaela; Sandhoff, Konrad

2009-11-01

187

Qualification of an LWBR-irradiated fuel assay gauge  

SciTech Connect

A production-irradiated fuel assay gauge (PIFAG) has been developed with the capability of determine, nondestructively, the total fissile fuel content (loading) of an irradiated fuel rod with a precision of 0.5% or better. This gauge was developed by the Bettis Atomic Power Laboratory under the technical direction of the US Department of Energy's Office of Naval Reactors to be used for proving breeding in the light water breeder reactor (LWBR). This paper presents nondestructive and destructive data that demonstrate the high precision, accuracy, and stability of the PIFAG. The PIFAG is being qualified by comparison of PIFAG results with destructive assay results for 17 rods, repeated assay at long time intervals of a selected number of rods of each type, and continuous monitoring with a normalization rod. These data demonstrate that the PIFAG meets the precision objectives of the fissile loading determination.

Tessler, G.; Beaudoin, B.R.; Beggs, W.J.; Freeman, L.B.; Goldberg, I.; Hecker, H.C.; Kahler, A.C.; Schick, W.C. Jr.; Simon, C.J.; Raab, H.F.

1986-01-01

188

Hybrid holographic non-destructive test system  

NASA Technical Reports Server (NTRS)

An automatic hybrid holographic non-destructive testing (HNDT) method and system capable of detecting flaws or debonds contained within certain materials are described. This system incorporates the techniques of optical holography, acoustical/optical holography and holographic correlation in determining the structural integrity of a test object. An automatic processing system including a detector and automatic data processor is used in conjunction with the three holographic techniques for correlating and interpreting the information supplied by the non-destructive systems. The automatic system also includes a sensor which directly translates an optical data format produced by the holographic techniques into electrical signals and then transmits this information to a digital computer for indicating the structural properties of the test object. The computer interprets the data gathered and determines whether further testing is necessary as well as the format of this new testing procedure.

Kurtz, R. L. (inventor)

1978-01-01

189

Emerging nondestructive inspection methods for aging aircraft  

SciTech Connect

This report identifies and describes emerging nondestructive inspection (NDI) methods that can potentially be used to inspect commercial transport and commuter aircraft for structural damage. The nine categories of emerging NDI techniques are: acoustic emission, x-ray computed tomography, backscatter radiation, reverse geometry x-ray, advanced electromagnetics, including magnetooptic imaging and advanced eddy current techniques, coherent optics, advanced ultrasonics, advanced visual, and infrared thermography. The physical principles, generalized performance characteristics, and typical applications associated with each method are described. In addition, aircraft inspection applications are discussed along with the associated technical considerations. Finally, the status of each technique is presented, with a discussion on when it may be available for use in actual aircraft maintenance programs. It should be noted that this is a companion document to DOT/FAA/CT-91/5, Current Nondestructive Inspection Methods for Aging Aircraft.

Beattie, A.; Dahlke, L.; Gieske, J. [and others

1994-01-01

190

Techniques for enhancing laser ultrasonic nondestructive evaluation  

SciTech Connect

Ultrasonic nondestructive evaluation is an extremely powerful tool for characterizing materials and detecting defects. A majority of the ultrasonic nondestructive evaluation is performed with piezoelectric transducers that generate and detect high frequency acoustic energy. The liquid needed to couple the high frequency acoustic energy from the piezoelectric transducers restricts the applicability of ultrasonics. For example, traditional ultrasonics cannot evaluate parts at elevated temperatures or components that would be damaged by contact with a fluid. They are developing a technology that remotely generates and detects the ultrasonic pulses with lasers and consequently there is no requirement for liquids. Thus the research in laser-based ultrasound allows them to solve inspection problems with ultrasonics that could not be done before. This technology has wide application in many Lawrence Livermore National Laboratory programs, especially when remote and/or non-contact sensing is necessary.

Candy, J; Chinn, D; Huber, R; Spicer, J; Thomas, G

1999-02-16

191

Nondestructive evaluation by acousto-ultrasonics  

NASA Technical Reports Server (NTRS)

Acousto-ultrasonics is an ultrasonic technique that was originally devised to cope with the particular problems associated with nondestructive evaluation (NDE) of fiber/polymer composite structures. The fiber/polymer composites are more attenuating to ultrasound than any other material presently of interest. This limits the applicability of high-frequency ultrasonics. A common use of ultrasound is the imaging of flaws internal to a structure by scattering from the interface with the flaw. However, structural features of composites can scatter ultrasound internally, thus obscuring the flaws. A need relative to composites is to be able to nondestructively measure the strength of laminar boundaries in order to assess the integrity of a structure. Acousto-ultrasonics has exhibited the ability to use the internal scattering to provide information for determining the strength of laminar boundaries. Analysis of acousto-ultrasonic signals by the wave ray paths that compose it leads to waveform partitioning that enhances the sensitivity to mechanical strength parameters.

Kautz, Harold E.

1988-01-01

192

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

193

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

194

Magnetoresistive sensors for nondestructive evaluation (Invited Paper)  

Microsoft Academic Search

New high-sensitivity solid-state magnetoresistive (MR) sensor technologies offer significant advantages in nondestructive evaluation (NDE) systems. A key advantage of MR sensors is a flat frequency response extending from dc to hundreds of MHz, making them particularly attractive for low-frequency and multi-frequency eddy current detection for deep-flaw detection and depth profiling. MR sensors are mass produced by thin film processing techniques

Albrecht Jander; Carl Smith; Robert Schneider

2005-01-01

195

Symbols for welding, brazing and nondestructive examination  

SciTech Connect

This book provides a method of conveying instructions to the welder or brazer by means of symbols which may have several parts. Detailed instructions and examples are provided so that the welding or brazing symbol may be constructed and interpreted to cover most welded or brazed designs. Also included is a system of symbols for informing the nondestructive examination technician as to the method, frequency and extent of examination required.

Not Available

1986-01-01

196

Human Factors and Ergonomics for Nondestructive Testing  

Microsoft Academic Search

Nondestructive testing (NDT) does rely heavily on human judgment and visual capability to identify any faults or defects on\\u000a the specimen at the end of the process. Despite the fact that a human plays an important role on the reliability of the NDT\\u000a test results, very little research work has been carried out to study the ergonomics and human factors

B. L. Luk; Alan H. S. Chan

197

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

198

Nondestructive Evaluation of Adhesively Bonded Joints  

NASA Technical Reports Server (NTRS)

The final report consists of 5 published papers in referred journals and a technical letter to the technical monitor. These papers include the following: (1) Comparison of the effects of debonds and voids in adhesive; (2) On the peak shear stresses in adhesive joints with voids; (3) Nondestructive evaluation of adhesively bonded joints by acousto-ultrasonic technique and acoustic emission; (4) Multiaxial fatigue life evaluation of tubular adhesively bonded joints; (5) Theoretical and experimental evaluation of the bond strength under peeling loads. The letter outlines the progress of the research. Also included is preliminary information on the study of nondestructive evaluation of composite materials subjected to localized heat damage. The investigators studied the effects of localized heat on unidirectional fiber glass epoxy composite panels. Specimens of the fiber glass epoxy composites were subjected to 400 C heat for varying lengths of time. The specimens were subjected to nondestructive tests. The specimens were then pulled to their failure and acoustic emission of these specimens were measured. The analysis of the data was continuing as of the writing of the letter, and includes a finite element stress analysis of the problem.

Nayeb-Hashemi, Hamid; Rossettos, J. N.

1997-01-01

199

Trends in nondestructive imaging of IC packages  

NASA Astrophysics Data System (ADS)

Since the industry-wide conversion to surface mount packages in the mid-1980's, nondestructive imaging of moisture induced delaminations and cracks in plastic packaged ICs by scanning acoustic microscopy has been a critically important capability. Subsurface imaging and phase analysis of echoes has allowed scanning acoustic microscopy to become the primary nondestructive technique for component level inspection of packaged ICs and is sensitive to defects that are undetectable by real time x-ray inspection. It has become the preferred method for evaluating moisture sensitivity, and for many package processes, provides more reliable detection of wire bond degradation than physical cross sectioning or conventional electrical testing. However, the introduction of new technologies such as ball grid array (BGA) and flip chip packages demands improvements in acoustic inspection techniques. Echoes from the laminated substrates in BGA packages produce interference problems. Phase inversion detection is an important advantage of pulse-echo imaging of molded surface mount packages. However, phase inversion is not always helpful for delamination detection in these new packages, due to the properties of the materials involved. The requirement to nondestructively inspect flip chip interconnect bumps has arisen. Alternative approaches such as through-transmission screening of BGAs and high frequency (>200 MHz) pulse-echo inspection of flip chip bumps are addressing these new issues. As the acoustic frequency approaches the limits dictated by attenuation, new methods of frequency-domain signal analysis will become important for routine inspection and may give acoustic microscopy a predictive capability.

Moore, T. M.; Hartfield, C. D.

1998-11-01

200

Testing Physical Models of Passive Membrane Permeation  

PubMed Central

The biophysical basis of passive membrane permeability is well understood, but most methods for predicting membrane permeability in the context of drug design are based on statistical relationships that indirectly capture the key physical aspects. Here, we investigate molecular mechanics-based models of passive membrane permeability and evaluate their performance against different types of experimental data, including parallel artificial membrane permeability assays (PAMPA), cell-based assays, in vivo measurements, and other in silico predictions. The experimental data sets we use in these tests are diverse, including peptidomimetics, congeneric series, and diverse FDA approved drugs. The physical models are not specifically trained for any of these data sets; rather, input parameters are based on standard molecular mechanics force fields, such as partial charges, and an implicit solvent model. A systematic approach is taken to analyze the contribution from each component in the physics-based permeability model. A primary factor in determining rates of passive membrane permeation is the conformation-dependent free energy of desolvating the molecule, and this measure alone provides good agreement with experimental permeability measurements in many cases. Other factors that improve agreement with experimental data include deionization and estimates of entropy losses of the ligand and the membrane, which lead to size-dependence of the permeation rate.

Leung, Siegfried S. F.; Mijalkovic, Jona; Borrelli, Kenneth; Jacobson, Matthew P.

2012-01-01

201

Nondestructive characterization of radioactive waste drums by gamma spectrometry: a Monte Carlo technique for efficiency calibration.  

PubMed

A semi-empirical non-destructive technique to assay radioactive waste drums is presented. The technique is based on gamma spectrometry performed using a portable NaI detector and Monte Carlo simulations using the MCNP code in order to derive the gamma ray detector efficiency for the volume source. The derivation of detector efficiency was performed assuming homogeneous distribution of the source activity within the matrix material. Moreover, the MCNP model was used to examine the effect of inhomogeneities in activity distribution, variation of matrix material density, and drum filling height on the accuracy of the technique, and to estimate the measurement bias. The technique was verified by estimating radioactivity levels in 25 drums containing ion exchange resin waste, and comparing the results of the non-destructive method against the analytical results of samples obtained from each drum. Satisfactory agreement between the two assay techniques was observed. The discussed technique represents a cost effective technology that can be used to assay low-activity, low-density waste drums provided the contribution to the gamma ray spectrum can be resolved. PMID:18049246

Tzika, Faidra; Savidou, Anastasia; Stamatelatos, Ion E

2007-11-01

202

Wireless passive radiation sensor  

DOEpatents

A novel measurement technique is employed using surface acoustic wave (SAW) devices, passive RF, and radiation-sensitive films to provide a wireless passive radiation sensor that requires no batteries, outside wiring, or regular maintenance. The sensor is small (<1 cm.sup.2), physically robust, and will operate unattended for decades. In addition, the sensor can be insensitive to measurement position and read distance due to a novel self-referencing technique eliminating the need to measure absolute responses that are dependent on RF transmitter location and power.

Pfeifer, Kent B; Rumpf, Arthur N; Yelton, William G; Limmer, Steven J

2013-12-03

203

Method of passivating semiconductor surfaces  

DOEpatents

A method is described for passivating Group III-V or II-VI semiconductor compound surfaces. The method includes selecting a passivating material having a lattice constant substantially mismatched to the lattice constant of the semiconductor compound. The passivating material is then grown as an ultrathin layer of passivating material on the surface of the Group III-V or II-VI semiconductor compound. The passivating material is grown to a thickness sufficient to maintain a coherent interface between the ultrathin passivating material and the semiconductor compound. In addition, a device formed from such method is also disclosed.

Wanlass, M.W.

1990-06-19

204

Expert system for transuranic waste assay  

SciTech Connect

Transuranic wastes are generated at the Savannah River Site (SRS) as a result of routine production of nuclear materials. These wastes contain Pu-238 and Pu-239 and are placed into lined 55-gallon waste drums. The drums are placed on monitored storage pads pending shipment to the Waste Isolation Pilot Plant in New Mexico. A passive-active neutron (PAN) assay system is used to determine the mass of the radioactive material within the waste drums. Assay results are used to classify the wastes as either low-level or transuranic (TRU). During assays, the PAN assay system communicates with an IBM-AT computer. A Fortran computer program, called NEUT, controls and performs all data analyses. Unassisted, the NEUT program cannot adequately interpret assay results. To eliminate this limitation, an expert system shell was used to write a new algorithm, called the Transuranic Expert System (TRUX), to drive the NEUT program and add decision making capabilities for analysis of the assay results. The TRUX knowledge base was formulated by consulting with human experts in the field of neutron assay, by direct experimentation on the PAN assay system, and by observing operations on a daily basis. TRUX, with its improved ability to interpret assay results, has eliminated the need for close supervision by a human expert, allowing skilled technicians to operate the PAN assay system. 4 refs., 1 fig., 4 tabs.

Zoolalian, M.L.; Gibbs, A.; Kuhns, J.D.

1989-01-01

205

46 CFR 151.03-38 - Nondestructive testing.  

Code of Federal Regulations, 2013 CFR

...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,...

2013-10-01

206

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. The design includes high R-Value assemblies, extremely tight construction, high performance doors and windows, solar thermal DHW, heat recovery ventilation, moveable external shutters and a high performance ductless mini-split heat pump. Cost analysis indicates that many of the measures implemented in this project did not meet the BA standard for cost neutrality. The ductless mini-split heat pump, lighting and advanced air leakage control were the most cost effective measures. The future challenge will be to value engineer the performance levels indicated here in modeling using production based practices at a significantly lower cost.

Hales, D.

2014-01-01

207

Moving to passive designs  

Microsoft Academic Search

The events at Fukushima Daiichi have greatly renewed the public focus on the safety of the existing fleet of nuclear reactors, especially as many US reactors share the same fundamental design—and safety systems—as the affected Japanese reactors. The authors explore the proposition that a transition to increasingly passive safety features in new advanced reactor designs— supplementing, and in some cases

Robert Rosner; Rebecca Lordan; Stephen Goldberg

2011-01-01

208

Passives and Their Meaning  

ERIC Educational Resources Information Center

An underlying representation for passive sentences in Mojave and Uto-Aztecan is proposed, and the broader issues that arise in extending the analysis to other languages and incorporating it in linguistic theory as a substantive language universal are explored. (Author/RM)

Langacker, Ronald W.; Munro, Pamela

1975-01-01

209

Nondestructive NMR technique for moisture determination in radioactive materials.  

SciTech Connect

This progress report focuses on experimental and computational studies used to evaluate nuclear magnetic resonance (NMR) spectroscopy and magnetic resonance imaging (MRI) for detecting, quantifying, and monitoring hydrogen and other magnetically active nuclei ({sup 3}H, {sup 3}He, {sup 239}Pu, {sup 241}Pu) in Spent nuclear fuels and packaging materials. The detection of moisture by using a toroid cavity NMR imager has been demonstrated in SiO{sub 2} and UO{sub 2} systems. The total moisture was quantified by means of {sup 1}H NMR detection of H{sub 2}O with a sensitivity of 100 ppm. In addition, an MRI technique that was used to determine the moisture distribution also enabled investigators to discriminate between bulk and stationary water sorbed on the particles. This imaging feature is unavailable in any other nondestructive assay (NDA) technique. Following the initial success of this program, the NMR detector volume was scaled up from the original design by a factor of 2000. The capacity of this detector exceeds the size specified by DOE-STD-3013-96.

Aumeier, S.; Gerald, R.E. II; Growney, E.; Nunez, L.; Kaminski, M.

1998-12-04

210

FIRST 100 T NON-DESTRUCTIVE MAGNET  

SciTech Connect

The first 100 T non-destructive (100 T ND) magnet and power supplies as currently designed are described. This magnet will be installed as part of the user facility research equipment at the National High Magnetic Field Laboratory (NHMFL) Pulsed Field Facility at Los Alamos National Laboratory. The 100 T ND magnet will provide a 100 T pulsed field of 5 ms duration (above 90% of full field) in a 15 mm diameter bore once per hour. Magnet operation will be non-destructive. The magnet will consist of a controlled power outer coil set which produces a 47 T platform field in a 225 mm diameter bore. Located within the outer coil set will be a 220 mm outer diameter capacitor powered insert coil. Using inertial energy storage a synchronous motor/generator will provide ac power to a set of seven ac-dc converters rated at 64 MW/80 MVA each. These converters will energize three independent coil circuits to create 170 MJ of field energy in the outer coil set at the platform field of 47 T. The insert will then be energized to produce the balance of the 100 T peak field using a 2.3 MJ, 18 kV (charged to 15 kV), 14.4 mF capacitor bank controlled with solid-state switches. The magnet will be the first of its kind and the first non-destructive, reusable 100 T pulsed magnet. The operation of the magnet will be described along with special features of its design and construction.

J. R. SIMS; ET AL

1999-10-01

211

Passive Ranging with Incoherent Systems.  

National Technical Information Service (NTIS)

Research Areas Include * Passive Ranging with a single image from a single- lens incoherent optical system * Extended Depth of Field Incoherent Optical Systems. ( i.e. passive ranging systems that operate over a very large object volume.) Specific Analysi...

W. Miceli, W. T. Cathey, E. R. Dowski, A. FitzGerrell

1995-01-01

212

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

213

Nondestructive readout for a superconducting flux qubit.  

PubMed

We present a new readout method for a superconducting flux qubit, based on the measurement of the Josephson inductance of a superconducting quantum interference device that is inductively coupled to the qubit. The intrinsic flux detection efficiency and backaction are suitable for a fast and nondestructive determination of the quantum state of the qubit, as needed for readout of multiple qubits in a quantum computer. We performed spectroscopy of a flux qubit and we measured relaxation times of the order of 80 micros. PMID:15525116

Lupa?cu, A; Verwijs, C J M; Schouten, R N; Harmans, C J P M; Mooij, J E

2004-10-22

214

Nondestructive characterization of lattice block material™  

NASA Astrophysics Data System (ADS)

Lattice Block Material™ (LBM™) is the name given to a new class of materials that makes use of the well-understood principles of trusses and space frames to create a variety of components having high strength to weight ratios. Differences in product design, materials selection, and manufacturing process, however, can lead to uncertainty as to the overall performance of a given end product. For this reason, a variety of nondestructive methods were utilized to characterize LBM™ for potential Navy applications, including, visual inspection, x-ray radiography, x-ray computed tomography, and infrared thermography. .

Lipetzky, Kirsten G.; Warren, Jeffrey M.

2002-05-01

215

Automation for nondestructive inspection of aircraft  

NASA Technical Reports Server (NTRS)

We discuss the motivation and an architectural framework for using small mobile robots as automated aids to operators of nondestructive inspection (NDI) equipment. We review the need for aircraft skin inspection, and identify the constraints in commercial airlines operations that make small mobile robots the most attractive alternative for automated aids for NDI procedures. We describe the design and performance of the robot (ANDI) that we designed, built, and are testing for deployment of eddy current probes in prescribed commercial aircraft inspections. We discuss recent work aimed at also providing robotic aids for visual inspection.

Siegel, M. W.

1994-01-01

216

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

217

Feynman variance-to-mean in the context of passive neutron coincidence counting  

NASA Astrophysics Data System (ADS)

Passive Neutron Coincidence Counting (PNCC) based on shift register autocorrelation time analysis of the detected neutron pulse train is an important Nondestructive Assay (NDA) method. It is used extensively in the quantification of plutonium and other spontaneously fissile materials for purposes of nuclear materials accountancy. In addition to the totals count rate, which is also referred to as the singles, gross or trigger rate, a quantity known as the reals coincidence rate, also called the pairs or doubles, is obtained from the difference between the measured neutron multiplicities in two measurement gates triggered by the incoming events on the pulse train. The reals rate is a measure of the number of time correlated pairs present on the pulse train and this can be related to the fission rates (and hence material mass) since fissions emit neutrons in bursts which are also detected in characteristic clusters. A closely related measurement objective is the determination of the reactivity of systems as they approach criticality. In this field an alternative autocorrelation signature is popular, the so called Feynman variance-to-mean technique which makes use of the multiplicity histogram formed the periodic, or clock-triggered opening of a coincidence gate. Workers in these two application areas share common challenges and improvement opportunities but are often separated by tradition, problem focus and technical language. The purpose of this paper is to recognize the close link between the Feynman variance-to-mean metric and traditional PNCC using shift register logic applied to correlated pulse trains. We, show using relationships for the late-gate (or accidentals) histogram recorded using a multiplicity shift register, how the Feynman Y-statistic, defined as the excess variance-to-mean ratio, can be expressed in terms of the singles and doubles rates familiar to the safeguards and waste assay communities. These two specialisms now have a direct bridge between them and we anticipate fruitful cross fertilization, for example on assay algorithms, including corrections for measurement item perturbation factors, and on data acquisition systems.

Croft, S.; Favalli, A.; Hauck, D. K.; Henzlova, D.; Santi, P. A.

2012-09-01

218

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

219

Complementary Electromagnetic Non-Destructive Evaluation  

NASA Astrophysics Data System (ADS)

The use of non-destructive evaluation (NDE) for defect detection and failure prediction in structures and specimens is widespread in energy industries, aimed at ageing power plants and pipelines, material degradation, fatigue and radiation damage, etc. At present there are no suitable electromagnetic NDE methods for the measurement and characterization of material degradation, in irradiated samples in particular, which is very important and timely for the nuclear power industry in the UK. This paper reports recent developments in the field of electromagnetic (EM) NDE at Newcastle University, including pulsed eddy current (PEC), pulsed magnetic flux leakage (PMFL), magnetic Barkhausen emission (MBE) and magneto-acoustic emission (MAE). As different EM methods have different strengths, an integrative EM framework is introduced. Case studies through the second round robin tests organized by the Universal Network for Magnetic Non-Destructive Evaluation (UNMNDE), representing eighteen leading research groups worldwide in the area of electromagnetic NDE, are reported. Twelve samples with different ageing times and rolling reduction ratios were tested using different magnetic methods among the UNMNDE members. Based on the studies, the complementary characteristics of electromagnetic techniques for NDE are discussed.

Tian, Gui Yun; Wilson, John; Morozov, Maxim

2011-06-01

220

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

221

Guidebook of nondestructive evaluation techniques for materials and structures  

NASA Technical Reports Server (NTRS)

Seventy nondestructive techniques for evaluating material and structures are described in guidebook. Standardized format facilitates comparison of their merits and limitations for solving various problems. Guide includes index of flaw types and tabulated guide to use of nondestructive evaluation techniques. Alternative technique names are cross-referenced.

Vary, A.

1974-01-01

222

Cost-risk optimization of nondestructive inspection level. Technical report  

Microsoft Academic Search

This paper develops a quantitative methodology for determining the nondestructive inspection (NDI) level that will result in a minimum cost product considering both type one inspection errors, acceptance of defective material units, and type two inspection errors, rejection of sound material units. This methodology represents an advance over fracture mechanics - nondestructive inspection (FM-NDI) design systems that do not consider

Johnson

1975-01-01

223

Advanced system for automating eddy-current nondestructive evaluation  

Microsoft Academic Search

Various nondestructive evaluation (NDE) techniques are widely used in the inspection of sub-surface flaws. This paper introduces the results of a research conducted to enhance the performance of eddy-current nondestructive evaluation (ECNDE) by developing an integrated computer based system. Advantages of this system include increasing test speed, while avoiding errors due to human factors. The system can be used to

Moustafa N. I. Fahmy; Essam A. Hashish; Ibrahim Elshafiey; I. Jannound

2000-01-01

224

Nondestructive Identification of Cold and Extremely Localized Single Molecular Ions  

Microsoft Academic Search

We demonstrate a simple and nondestructive method for identification of a single molecular ion sympathetically cooled by a single laser cooled atomic ion in a linear Paul trap. The technique is based on a precise nondestructive determination of the molecular ion mass through a measurement of the eigenfrequency of a common motional mode of the two ions. The demonstrated mass

M. Drewsen; A. Mortensen; R. Martinussen; P. Staanum; J. L. Sørensen

2004-01-01

225

Magnetic Field Exposure in a Nondestructive Testing Operation  

Microsoft Academic Search

Nondestructive testing is any technique used to inspect the integrity of a manufactured item without diminishing its future usefulness. Magnetic particle inspection is one type of nondestructive testing that uses electromagnetism in the inspection procedure, thus potentially exposing the operator to magnetic fields. During magnetic particle inspection, investigators took peak magnetic field measurements of 8 turbine engine shafts at a

Julia F. Lippert; Steven E. Lacey; Kathleen J. Kennedy; Nurtan A. Esmen; Jeanine M. Buchanich; Gary M. Marsh

2007-01-01

226

Neutron measurement techniques for the nondestructive analysis of irradiated fuel assemblies  

SciTech Connect

Nondestructive measurement of the passive neutron signatures of irradiated light-water reactor fuel assemblies is a rapid and simple technique for verifying operator-declared exposure values. Fuel assemblies from four different reactor facilities have been measured to establish the functional relationship between the operator-declared exposure values and the experimentally measured neutron emission rates. Experimentally measured neutron emission rates of small fuel rod sections have been shown to agree with the predicted results from our calculational model. Destructive results for the actinide isotopes also agreed very well with our prediction. Neutron emission rates varied by 30 to 40% between opposite corners of the source fuel assembly. Symmetrical neutron detector systems that measure all sides simultaneously were evaluated.

Phillips, J.R.; Bosler, G.E.; Halbig, J.K.; Klosterbuer, S.F.; Lee, D.M.; Menlove, H.O.

1981-11-01

227

Passive chevron replicator  

NASA Technical Reports Server (NTRS)

There is described a passive replicator device to be used in magnetic bubble domain systems. The replicator is passive, i.e., does not require an active element such as a current source or the like, and both propagates and replicates bubble domains. In a preferred embodiment, the replicator uses chevron type elements arranged in an appropriate pattern so as to interact with a pair of propagation paths wherein bubble domains are propagated. A bubble in one propagation path is routinely transferred therealong and, concurrently, replicated by the instant device into another propagation path. A plurality of elements arranged in juxtaposition to the chevrons assists in controlling the propagation of the bubbles through the respective propagation paths and, at the appropriate time, provides a cutting action wherein a bubble which is elongated between the chevrons of the two propagation paths is split into two separate bubbles.

Oeffinger, Thomas R. (Inventor); Tocci, Leonard R. (Inventor)

1977-01-01

228

Delayed gamma technique for fissile material assay  

SciTech Connect

Research sponsored by the Next Generation Safeguards Initiative are investigating several non-destructive assay techniques for the quantification of fissile plutonium mass in spent nuclear fuel assemblies. AppHcation of the delayed gamma signatures is investigated in this context. The objective of the research is to assess whether the delayed gamma assay instrument can provide sufficient sensitivity, isotope specificity and accuracy as required in nuclear material safeguards. This effort includes theoretical and experimental components for the optimal combination of interrogation parameters. A new modeling algorithm offering a high level of detail was developed specifically for this purpose and was validated in series of benchmark experiments. Preliminary modeling of the delayed gamma response from spent fuel assemblies was accomplished offering a future direction for the design process.

Mozin, Vladimir [Los Alamos National Laboratory; Tobin, Stephen [Los Alamos National Laboratory; Vujie, Jasmina [UC BERKELEY; Hunt, Alan [IDAHO ACCELERATOR CENTER

2010-01-01

229

Passivation of stainless steel  

Microsoft Academic Search

This paper, the 19th in a series of articles on the hygienic design of food processing equipment published in TIFS, introduces the first joint EHEDG\\/3-A Update article in the series, a set of guidelines for the hygienic passivation of stainless steel surfaces intended for food-contact use. These guidelines have been prepared on behalf of the US-based 3-A Steering Committee and

R. R Maller

1998-01-01

230

Passive solar heating analysis  

SciTech Connect

A presentation of solar heating analysis methods developed at the Los Alamos National Laboratory, focusing on small residential and commercial buildings. This book gives building designers a solar sizing and evaluation guide. Tabulated values for 223 North American locations make the methods potentially useful anywhere in the United States and Canada. It establishes 30 guidelines that range from general rules relating to conservation, solar area and orientation, to passive solar system types.

Not Available

1984-01-01

231

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

232

Nondestructive monitoring of carotenogenesis in Haematococcus pluvialis via whole-cell optical density spectra.  

PubMed

We investigated the feasibility of rapid, nondestructive assay of carotenoid-to-chlorophyll (Car/Chl) ratio and total carotenoids (Car) in cell suspensions of the carotenogenic chlorophyte Haematococcus pluvialis Flotow under stressful conditions. Whole-cell spectra are characterized by variable nonlinear contributions of Car and chlorophylls (Chl), with a strong influence of Car packaging and sieve effect inherent to stressed H. pluvialis cells. Nevertheless, nondestructive assay of Car/Chl in the range of 0.55-31.2 (Car content up to 188 mg L(-1); 5.4 % of the cell dry weight) turned to be achievable with a simple spectrophotometer lacking an integrating sphere upon deposition of the cells on glass fiber filters. The scattering-corrected optical density (OD) in the blue-green region of the whole-cell spectrum, normalized to that in the red maximum of Chl absorption (OD500/OD678), was tightly related (r (2) = 0.96) with the Car/Chl ratio found in extracts. Some features such as the amplitude and position of the minimum of the normalized first-derivative OD whole-cell spectra also exhibited a strong (r (2) > 0.90) nonlinear correlation with Car/Chl. These spectral indices were also tightly related with Car, but the slope of the relationship varied with the stressor intensity. The importance of calibration over the widest possible range of pigment contents and a correct choice of biomass load per filter are emphasized. The advantages and limitations of nondestructive monitoring of carotenogenesis in H. pluvialis are discussed in view of its possible application in optical sensors for laboratory cultivation and mass production systems of the algae. PMID:23318838

Solovchenko, Alexei; Aflalo, Claude; Lukyanov, Alexander; Boussiba, Sammy

2013-05-01

233

Monte-Carlo Application for Nondestructive Nuclear Waste Analysis  

NASA Astrophysics Data System (ADS)

Radioactive waste has to undergo a process of quality checking in order to check its conformance with national regulations prior to its transport, intermediate storage and final disposal. Within the quality checking of radioactive waste packages non-destructive assays are required to characterize their radio-toxic and chemo-toxic contents. The Institute of Energy and Climate Research - Nuclear Waste Management and Reactor Safety of the Forschungszentrum Jülich develops in the framework of cooperation nondestructive analytical techniques for the routine characterization of radioactive waste packages at industrial-scale. During the phase of research and development Monte Carlo techniques are used to simulate the transport of particle, especially photons, electrons and neutrons, through matter and to obtain the response of detection systems. The radiological characterization of low and intermediate level radioactive waste drums is performed by segmented ?-scanning (SGS). To precisely and accurately reconstruct the isotope specific activity content in waste drums by SGS measurement, an innovative method called SGSreco was developed. The Geant4 code was used to simulate the response of the collimated detection system for waste drums with different activity and matrix configurations. These simulations allow a far more detailed optimization, validation and benchmark of SGSreco, since the construction of test drums covering a broad range of activity and matrix properties is time consuming and cost intensive. The MEDINA (Multi Element Detection based on Instrumental Neutron Activation) test facility was developed to identify and quantify non-radioactive elements and substances in radioactive waste drums. MEDINA is based on prompt and delayed gamma neutron activation analysis (P&DGNAA) using a 14 MeV neutron generator. MCNP simulations were carried out to study the response of the MEDINA facility in terms of gamma spectra, time dependence of the neutron energy spectrum, neutron flux distribution. The validation of the measurements simulations with Mont-Carlo transport codes for the design, optimization and data analysis of further P&DGNAA facilities is performed in collaboration with LMN CEA Cadarache. The performance of the prompt gamma neutron activation analysis (PGNAA) for the nondestructive determination of actinides in small samples is investigated. The quantitative determination of actinides relies on the precise knowledge of partial neutron capture cross sections. Up to today these cross sections are not very accurate for analytical purpose. The goal of the TANDEM (Trans-uranium Actinides' Nuclear Data - Evaluation and Measurement) Collaboration is the evaluation of these cross sections. Cross sections are measured using prompt gamma activation analysis facilities in Budapest and Munich. Geant4 is used to optimally design the detection system with Compton suppression. Furthermore, for the evaluation of the cross sections it is strongly needed to correct the results to the self-attenuation of the prompt gammas within the sample. In the framework of cooperation RWTH Aachen University, Forschungszentrum Jülich and the Siemens AG will study the feasibility of a compact Neutron Imaging System for Radioactive waste Analysis (NISRA). The system is based on a 14 MeV neutron source and an advanced detector system (a-Si flat panel) linked to an exclusive converter/scintillator for fast neutrons. For shielding and radioprotection studies the codes MCNPX and Geant4 were used. The two codes were benchmarked in processing time and accuracy in the neutron and gamma fluxes. Also the detector response was simulated with Geant4 to optimize components of the system.

Carasco, C.; Engels, R.; Frank, M.; Furletov, S.; Furletova, J.; Genreith, C.; Havenith, A.; Kemmerling, G.; Kettler, J.; Krings, T.; Ma, J.-L.; Mauerhofer, E.; Neike, D.; Payan, E.; Perot, B.; Rossbach, M.; Schitthelm, O.; Schumann, M.; Vasquez, R.

2014-06-01

234

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

235

Direct fissile assay of highly enriched UF/sub 6/ using random self-interrogation and neutron coincidence response  

SciTech Connect

A new nondestructive method for direct assay of /sup 235/U mass contained in Model 5A uranium hexafluoride (UF/sub 6/) product storage cylinders has been successfully tested in the laboratory and under field conditions. The technique employs passive neutron self-interrogation and uses the ratio of coincidences-to-totals counts as a measure of bulk fissile mass. The accuracy of the method is 6.8% (1 sigma) based on field measurements of 44 Model 5A cylinders, 11 of which were either only partially filled or contained reactor return material. The cylinders contained UF/sub 6/ with enrichments from 5.96% to 97.6%. Count times were 3 to 6 min depending on /sup 235/U mass. Samples ranged from below 1 kg to over 16 kg of /sup 235/U. Because the method relies primarily on fast neutron self-interrogation, complete sampling of the UF/sub 6/ takes place. This feature alleviates inhomogeneity problems and offers increased assurance of the presence of stated amounts of bulk fissile material as compared with current verification methods.

Stewart, J.E.; Menlove, H.O.

1983-01-01

236

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

237

Thermographic nondestructive evaluation: overview of recent progress  

NASA Astrophysics Data System (ADS)

This paper presents a summary of recent research activities carried out at our laboratory in the field of Infrared Thermography for Nondestructive Evaluation (TNDE). First, we explore the latest developments in signal improvement. We describe three approaches: multiple pulse stimulation; the use of Synthetic Data for de-noising of the signal; and a new approach derived from the Fourier diffusion equation called the Differentiated Absolute Contrast method (DAC). Secondly, we examine the advances carried out in inverse solutions. We describe the use of the Wavelet Transform to manage pulsed thermographic data, and we present a summary on Neural Networks for TNDE. Finally, we look at the problem of complex geometry inspection. In this case, due to surface shape, heat variations might be incorrectly identified as flaws. We describe the Shape-from-Heating approach and we propose some potential research avenues to deal with this problem.

Ibarra-Castanedo, Clemente; Galmiche, Francois; Darabi, Akbar; Pilla, Mariacristina; Klein, Matthieu; Ziadi, Adel; Vallerand, Steve; Pelletier, Jean-François; Maldague, Xavier P.

2003-04-01

238

Quantitative nondestructive evaluation: Requirements for tomorrow's reliability  

NASA Technical Reports Server (NTRS)

Quantitative Nondestructive Evaluation (QNDE) is the technology of measurement, analysis, and prediction of the state of material/structural systems for safety, reliability, and mission assurance. QNDE has impact on everyday life from the cars we drive, the planes we fly, the buildings we work or live in, literally to the infrastructure of our world. Here, researchers highlight some of the new sciences and technologies that are part of a safer, cost effective tomorrow. Specific technologies that are discussed are thermal QNDE of aircraft structural integrity, ultrasonic QNDE for materials characterization, and technology spinoffs from aerospace to the medical sector. In each case, examples are given of how new requirements result in enabling measurement technologies, which in turn change the boundaries of design/practice.

Heyman, Joseph S.

1991-01-01

239

Non-destructive sampling of a comet  

NASA Astrophysics Data System (ADS)

Various conditions which must be met for the development of a nondestructive sampling and acquisition system are outlined and the development of a new robotic sampling system suited for use on a cometary surface is briefly discussed. The Rosetta mission of ESA will take samples of a comet nucleus and return both core and volatile samples to earth. Various considerations which must be taken into account for such a project are examined including the identification of design parameters for sample quality; the identification of the most probable site conditions; the development of a sample acquisition system with respect to these conditions; the production of model materials and model conditions; and the investigation of the relevant material properties. An adequate sampling system should also be designed and built, including various tools, and the system should be tested under simulated cometary conditions.

Jessberger, H. L.; Kotthaus, M.

1991-04-01

240

Non-destructive evaluation of composites  

NASA Technical Reports Server (NTRS)

The composite materials have been used in aerospace industries for quite some time. Several non-destructive evaluation (NDE) methods have been developed to inspect composites in order to detect flaws, matrix cracking, and delamination. These methods include ultrasonics, acoustic emission, shearography, thermography, X-ray, and digital image correlation. The NDE Branch of Marshall Space Flight Center has recently acquired a thermal imaging NDE system. The same system has been used at NASA Langley Research Center for detecting disbonds. In order to compare different NDE methods, three carbon/carbon composite panels were used for experiment using ultrasonic C-scan, shearography, and thermography methods. These panels have teflon inserts to simulate the delamination between plies in a composite panel. All three methods have successfully located the insert. The experiment and results are presented in the following sections.

Chu, Tsuchin Philip

1996-01-01

241

Non-destructive testing method and apparatus  

DOEpatents

Non-destructive testing apparatus may comprise a photon source and a source material that emits positrons in response to bombardment of the source material with photons. The source material is positionable adjacent the photon source and a specimen so that when the source material is positioned adjacent the photon source it is exposed to photons produced thereby. When the source material is positioned adjacent the specimen, the specimen is exposed to at least some of the positrons emitted by the source material. A detector system positioned adjacent the specimen detects annihilation gamma rays emitted by the specimen. Another embodiment comprises a neutron source and a source material that emits positrons in response to neutron bombardment.

Akers, Douglas W. (Idaho Falls, ID)

2011-10-04

242

Specification and acceptance in nondestructive testing  

SciTech Connect

Nondestructive testing is often defined as the detection of defects in materials by using techniques that do not damage the product tested. For the user, a supply without defects is a reliable one, i.e., able to perform a required function under stated conditions for a stated period of time. For the quality manager, a supply without defects is one complying with specifications. This is why the vocabulary of quality control has opted for the following definition: [open quotes]Defect: the nonfulfillment of specified requirements for a characteristic of an item[close quotes]. In this case too, the author has to define the state of a characteristic and shall prefer to employ the word [open quotes]nonconformity[close quotes]. The specifier cannot only consider supplies in their totality, but must also look for the reasons for any failures. The performance of a supply may be reduced by the presence of variations in the physical, chemical, or structural properties of the material. Finally, the nondestructive testing inspector measures the variations of a physical quantity that are related to the presence of discontinuities. After completing the supply inspection and according to the type of data processing, the NDT inspector in fact measures the peak height on a diagram or the spotted area on an image. The defect is thus, as for the specifier, an item and shall employ the word [open quotes]signal[close quotes]. It is clear that, in the definition of NDT given at the beginning, the word [open quotes]defect[close quotes] must be taken in the sense of [open quotes]discontinuity[close quotes]. This is why the author shall prefer to define NDT as the verification of the homogeneity of a supply without its being damaged; by [open quotes]homogeneity[close quotes] it is meant that there is no significant difference with respect to samples taken from the supply.

Perdijon, J. (CEA, Centre d'Etudes Nucleaires, Grenoble (France))

1993-07-01

243

Nondestructive evaluation of fatigue in titanium alloys  

SciTech Connect

Dissipated heat has been measured by thermographic technique during fatigue experiments on Ti-6Al-4V. Surface temperature of the specimen was found sensitive to the amount of fatigue damage accumulated in the material. An increased heat dissipation due to fatigue can be related to continuous change in the microstructure (increased dislocation density, stacking faults, etc.) of the material. A method based on passive thermography can be proposed to monitor damage accumulation in Ti-6Al-4V due to cyclic loading.

Roesner, H.; Meyendorf, N.; Sathish, S.; Matikas, T.E.

2000-07-01

244

Hybrid chemical and nondestructive-analysis technique  

SciTech Connect

A hybrid chemical/NDA technique has been applied at the Los Alamos National Laboratory to the assay of plutonium in ion-exchange effluents. Typical effluent solutions contain low concentrations of plutonium and high concentrations of americium. A simple trioctylphosphine oxide (TOPO) separation can remove 99.9% of the americium. The organic phase that contains the separated plutonium can be accurately assayed by monitoring the uranium L x-ray intensities.

Hsue, S.T.; Marsh, S.F.; Marks, T.

1982-01-01

245

Hybrid chemical and nondestructive analysis technique  

SciTech Connect

A hybrid chemical/NDA technique has been applied at the Los Alamos National Laboratory to the assay of plutonium in ion-exchange effluents. Typical effluent solutions contain low concentrations of plutonium and high concentrations of americium. A simple trioctylphosphine oxide (TOPO) separation can remove 99.9% of the americium. The organic phase that contains the separated plutonium can be accurately assayed by monitoring the uranium L x-ray intensities.

Hsue, S.T.; Marsh, S.F.; Marks, T.

1983-01-01

246

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

247

Passive Immunization Against Poliomyelitis  

PubMed Central

Poliomyelitis has gone from being one of the worst scourges of the 20th century to nearing eradication in the 21st. This success is well known to be attributable to the Salk inactivated and Sabin attenuated poliovirus vaccines. However, before introduction of these vaccines, William McDowall Hammon of the University of Pittsburgh Graduate School of Public Health led the first major breakthrough in prevention of the disease by using passive immunization in one of the earliest double-blind, placebo-controlled clinical trials. This study provided the first evidence that antibodies to poliovirus could prevent the disease in humans.

Rinaldo, Charles R.

2005-01-01

248

Passive-solar construction handbook  

NASA Astrophysics Data System (ADS)

An identification and explanation of pertinent considerations in the construction of passively solar heated buildings are presented. Toward that end, the handbook discusses solar design principles, site planning and access, system components, construction details, financial considerations and other items which are essential considerations in passive solar design. The handbook was designed for a multitude of uses: as an instructional tool in workshops and seminars; as a compendium of passive solar design elements; and, as a reference guide to building trade professionals entering passive solar construction.

1981-09-01

249

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

250

FPGA based time domain Passivity Observer and Passivity Controller  

Microsoft Academic Search

In this paper, field programmable gate array (FPGA) based time domain passivity observer and passivity controller is proposed to improve the stability range of haptic interfaces. A simplified PO\\/PC algorithm is implemented on FPGA for improving the control efficiency. Thanks to the fast sampling rate and the parallel processing ability of the FPGA, the PO\\/PC can be updated irregularly only

Beibei Han; Jee-Hwan Ryu; Il-Kyun Jung

2009-01-01

251

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

252

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

253

Advanced Nondestructive Evaluation (NDE) Sensor Modeling For Multisite Inspection.  

National Technical Information Service (NTIS)

The Advanced Nondestructive Evaluation (NDE) Sensor Modeling for Multisite Inspection program has developed finite element models (FEM) of electromagnetic NDE for optimizing the inspection of aging aircraft structure. The program found excellent correlati...

B. Koltenbah L. Udpa L. Xin R. Bossi Y. Deng

2008-01-01

254

Nondestructive Evaluation of Electron-Beam Braze Joins.  

National Technical Information Service (NTIS)

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...

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

1981-01-01

255

Development of Nondestructive Tests for the Evaluation of Bonded Materials.  

National Technical Information Service (NTIS)

Data obtained in the surface condition study are presented. Electric field reflectometry, at 1 KHz and 9.8 GHz, and gas-phase ultrasonic transmission methods are detailed as possible methods for nondestructively evaluating substrate surfaces. (Author)

J. R. Zurbrick

1970-01-01

256

Role of nondestructive evaluation in life cycle management.  

National Technical Information Service (NTIS)

This paper provides an overview of some common nondestructive evaluation (NDE) methods and several examples for the use of different NDE techniques throughout the life cycle of a product. NDE techniques are being used to help determine material properties...

H. Martz

1997-01-01

257

Non-Destructive Inspection by Infrared Imaging Spectroscopy. Phase 1.  

National Technical Information Service (NTIS)

The objective of the Phase I effort was to investigate the applicability of infrared imaging spectroscopy to multiple Non-Destructive Inspection (NDI) applications. The program demonstrated object discrimination using an algorithm which post-processes an ...

M. Dombrowski V. Moore

1994-01-01

258

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

259

Nondestructive method for reconnecting aluminum metallization on integrated circuits  

Microsoft Academic Search

A failure analysis technique for reconnecting aluminum metallization on planar IC devices is described. The technique, utilizing a conductive paint deposited on the device surface, is nondestructive and easily removable.

A. D. Zubatkin

1979-01-01

260

Nondestructive method for reconnecting aluminum metallization on integrated circuits.  

PubMed

A failure analysis technique for reconnecting aluminum metallization on planar IC devices is described. The technique, utilizing a conductive paint deposited on the device surface, is nondestructive and easily removable. PMID:18699636

Zubatkin, A D

1979-07-01

261

Nondestructive Inspection Career Ladder AFSC 427X2.  

National Technical Information Service (NTIS)

Results of a Nondestructive Inspection career ladder USAF Job Inventory are based on the responses of 661 of the 810 total assigned or 82 percent of the total ladder population. Job groups identified included Branch Supervisors, Administrators, NCOICs of ...

1979-01-01

262

Reliability of Nondestructive Examination. Chapters 7 - 11. Volume 2.  

National Technical Information Service (NTIS)

This eighteen-chapter, three-volume study evaluates the various nondestructive examination (NDE) techniques now used to detect flaws in components of nuclear systems so that the reliability of the techniques may be increased. The significance of flaws at ...

S. H. Bush

1983-01-01

263

Dielectric Non-Destructive Analysis of Adhesive Bonded Structures.  

National Technical Information Service (NTIS)

An investigation was conducted aimed at developing dielectric spectroscopy as a non-destructive inspection tool to assess aging of adhesive bonded structures. Dielectric spectroscopy was found to be a sensitive tool capable of detecting defects and absorb...

J. Mijovic

2004-01-01

264

Method of and Apparatus for Non-Destructively Testing Concrete.  

National Technical Information Service (NTIS)

The patent application relates generally to methods of, and apparatus for, testing concrete, and more particularly, to a method of and apparatus for non-destructively testing concrete by impacting the concrete and monitoring induced vibrational energy usi...

M. Gutierrez P. F. Enger

1978-01-01

265

A Review of Non-destructive Detection for Fruit Quality  

NASA Astrophysics Data System (ADS)

An overview of non-destructive detection in quality of post-harvest fruit was presented in this paper, and the research and application were discussed. This paper elaborated the fruit quality detection methods which were based on one of the following properties: optical properties, sonic vibration, machine vision technique, nuclear magnetic resonance (NMR), electronic noses, electrical properties, computed tomography. At last, the main problems of non-destructive detection in application were also explained.

Gao, Haisheng; Zhu, Fengmei; Cai, Jinxing

266

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

267

Electro-thermography technique for nondestructive testing (NDT) applications  

Microsoft Academic Search

In this paper, Electro-Thermography is introduced in nondestructive testing applications. Electro-Thermography is one of the novel active thermography techniques for nondestructive testing. It gains the advantages from the optical and electromagnetic properties in full-field, non-contact, high inspection speed, and sensitivity in geometry variation. It is mostly applicable to all kind of ferrous-metal, some composites materials. A fundamental difference among electro-thermography

Y. S. Chen; Y. Y. Hung; L. Liu

2008-01-01

268

Critical reflections on non-destructive testing of concrete  

Microsoft Academic Search

Sclerometer tests, the ultrasonic pulse velocity method, the acoustic emission technique and combined non-destructive methods\\u000a for testing concrete properties are discussed. Examples and test results obtained by investigations with rigid and flexible\\u000a loading plantens show the efficiency of additional non-destructive testing. Finally, the NDT methods under consideration as\\u000a independent testing tools are critically analysed under several aspects.

G. Schickert

1984-01-01

269

On-orbit passive thermography  

Microsoft Academic Search

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 extravehicular activity (EVA, or spacewalk) compatible infrared camera developed by NASA engineers. Data was collected both

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

2008-01-01

270

Passive cooling effects of courtyards  

Microsoft Academic Search

The passive cooling effects of a courtyard of a small building were determined numerically, employing an energy-analysis software developed for that purpose. The passive cooling features considered were the shading effects of courtyard walls and two large trees (of various shapes) planted immediately next to the south wall of the building, the presence of a pool, a lawn and flowers

H. Safarzadeh; M. N. Bahadori

2005-01-01

271

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

272

Robust passive piezoelectric shunt dampener  

Microsoft Academic Search

This paper introduces a new multiple mode passive piezoelectric shunt damping technique. The robust passive piezoelectric shunt controller is capable of damping multiple structural modes and maybe less susceptible to variations in environmental conditions that can severely effect the performance of other controllers. The proposed control scheme is validated experimentally on a piezoelectric laminated plate structure.

Sam Behrens; Andrew J. Fleming; S. O. R. Moheimani

2003-01-01

273

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

274

Photorefractive nondestructive memory with Kitty-type conjugator  

NASA Astrophysics Data System (ADS)

In this report, we propose a photorefractive (PR) nondestructive memory with a Kitty-type phase conjugate mirror (Kitty PCM). Nondestructive readout without any fixing technique and high quality image rewriting can be achieved in this memory. An optical feedback circuit including a Kitty PCM is added on to the usual PR memory in the nondestructive reading method. The nondestructive readout means that the recorded data of the dynamic hologram, generally erased by the exposure of the reading beam, is maintained by only all-optical configuration. The nondestructive readout in this memory is achieved by the hologram rewriting effect that is generated by the reillumination of the diffraction beam reflected by a phase conjugate mirror. But a conventional Cat-type self-pumped phase conjugate mirror (Cat SPPCM) has insufficient reflectivity to obtain large feedback rate required for this nondestructive readout. In this report, we calculate and experiment on the phase conjugate reflectivity and the time response property of the Kitty PCM and show it has the advantages of high reflectivity and fast response time. We perform the experiment on our rewritable PR memory using BaTiO3 crystals and demonstrate the long time reading over 18 minutes is achieved in this memory.

Funakoshi, Hisatoshi; Okamoto, Atsushi

2003-08-01

275

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

276

Magnetoresistive sensors for nondestructive evaluation (Invited Paper)  

NASA Astrophysics Data System (ADS)

New high-sensitivity solid-state magnetoresistive (MR) sensor technologies offer significant advantages in nondestructive evaluation (NDE) systems. A key advantage of MR sensors is a flat frequency response extending from dc to hundreds of MHz, making them particularly attractive for low-frequency and multi-frequency eddy current detection for deep-flaw detection and depth profiling. MR sensors are mass produced by thin film processing techniques similar to integrated circuit manufacturing, dramatically reducing the cost per sensor. The fabrication process is compatible with silicon circuit technology, allowing integration of sensors with on-chip signal processing. MR sensors can easily be produced in dense arrays for rapid, single-pass scanning of large areas. The small size and low power consumption of these solid-state magnetic sensors enable the assembly of compact arrays of sensors on a variety of substrates as well as on-chip sensor arrays. Arrays have been fabricated with sensor spacing as small as 5 ?m. This paper presents a review of the state of the art in MR sensors and applications in NDE. The physical principles, manufacturing process, and performance characteristics of the three main types of MR devices, anisotropic magnetoresistance (AMR), giant magnetoresistance (GMR) and tunneling magnetoresistance (TMR) are discussed. Their performance is compared to other magnetic sensor technologies for NDE applications. Finally, we provide a comprehensive review of the literature on NDE applications of MR sensors.

Jander, Albrecht; Smith, Carl; Schneider, Robert

2005-05-01

277

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.

2012-03-01

278

Nondestructive inspection of a composite missile launcher  

NASA Astrophysics Data System (ADS)

Lighter weight alternatives are being sought to replace metallic components currently used in high performance aviation and missile systems. Benefits of lightweight, high strength carbon fiber reinforced composites in missile launchers and rocket motor cases include improved fuel economy, increased flight times, enhanced lethality and/or increased velocity. In this work, various nondestructive inspection techniques are investigated for the damage assessment of a composite missile launcher system for use in U.S. Army attack helicopters. The launcher system, which includes rails and a hardback, can be subject to impact damage from accidental tool drops, routine operation, and/or ballistic threats. The composite hardback and the launch rails both have complex geometries that can challenge the inspection process. Scanning techniques such as line scanning thermography, ultrasonic, and acousto-ultrasonics will be used and compared to determine damage detection accuracy, reliability, and efficiency. Results will also be compared with visual observations to determine if there is a correlation. The goal is to establish an inspection method that quickly and accurately assesses damage extent in order to minimize service time and return the missile system back into the field [1].

Ley, O.; Chung, S.; Butera, M.; Valatka, T.; Triplett, M. H.; Godinez, V.

2012-05-01

279

Corrosion quantification by different nondestructive inspection methods  

NASA Astrophysics Data System (ADS)

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 the amount of material lost. The NDI methods were chosen to represent different methods that could detect the presence of corrosion and digitize the data for analysis later to determine percent material lost. The NDI methods evaluated were computed tomography, pulse-echo ultrasonic c-scan, eddy current c-scan, thermography and digital radiography. Microscopy cross sectioning was also performed to visually document the corrosion damage. This data was used to compare the effectiveness of the NDI methods for detecting and quantifying corrosion damage and was used in the reanalysis of pre-corroded crack growth data. The results of NDI portion of this study are presented.

Rutherford, Paul S.; Luzar, Joe J.

1999-01-01

280

MIMO array imaging for ultrasonic nondestructive testing  

NASA Astrophysics Data System (ADS)

Ultrasonic sensor arrays continue to be broadly applied for nondestructive material testing. Generally, conventional beamforming techniques have been the favorite approach to generate images from the sensor array data. In this paper, we examine the use of multiple-input multiple-output (MIMO) ultrasonic processing technique for imaging internal structures of materials. The goal is to identify and locate potential defects and anomalies. The imaging technique is comprised of excitation of transmitting sensors with sequential or orthogonal wideband signals, matched filtering, and adaptive weighting. The weighting of the signals at the receiver takes into account the transducer ultrasound radiation patterns. The MIMO technique is particularly attractive for ultrasonic imaging, as the different bistatic combinations of transmit and receive sensor pairs allows effective and simple formations of virtual arrays with extended apertures and denser spatial sampling. As such, high-resolution images can be generated with fewer or available transducers. The performance of this technique is experimentally examined using test specimens with artificially drilled small size flat bottom holes that simulate defects. One-dimensional and two-dimensional array configurations are used to form desired virtual arrays and their respective imaging capabilities are evaluated and compared.

Demirli, Ramazan; Rivenq, Xavier; Zhang, Yimin D.; Ioana, Cornel; Amin, Moeness G.

2011-03-01

281

Operation of the EPRI Nondestructive Evaluation Center  

SciTech Connect

This report describes the Electric Power Research Institute (EPRI) funded nondestructive evaluation (NDE) and life assessment project activities carried out at the EPRI NDE Center in 1989. The primary support for this program is provided through contract RP 1570-2 with the EPRI Nuclear Division. Supplementary funding is provided by other contracts with the EPRI Nuclear and Generation and Storage Divisions. The major objective of this program is to provide improved and field-qualified NDE equipment, procedures, and personnel training to the electric utility industry. A second program objective involves the validation, provision, and maintenance of life assessment codes for selected plant components. Significant assistance has been provided to the utility industry under this project in the form of improved, field-theory equipment and procedures; critically needed assessments of inspection method capability; demonstrations of effectiveness of examination methods; rapid response for critical, short-term problems; assistance with selected life assessment computer codes; and training for specific utility industry needs. These efforts have specifically involved heat exchanger, piping, steam turbine, generator, and heavy section problems. Certain components of both nuclear and fossil plants have been addressed.

Stone, R.M.; Ammirato, F.V.; Becker, F.L.; Jeong, Y.H.; Krzywosz, K.J.; MacDonald, D.E.; Nottingham, L.D.; Selby, G.P.; Shankar, R.; Stephens, H.M.; Stramm, J.N.; Walker, S.M.; Willetts, A.J. (Jones (J.A.) Applied Research Co., Charlotte, NC (USA))

1990-09-01

282

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

283

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

284

Passive containment cooling system  

DOEpatents

A passive containment cooling system includes a containment vessel surrounding a reactor pressure vessel and defining a drywell therein containing a non-condensable gas. An enclosed wetwell pool is disposed inside the containment vessel, and a gravity driven cooling system (GDCS) pool is disposed above the wetwell pool in the containment vessel and is vented to the drywell. An isolation pool is disposed above the GDCS pool and includes an isolation condenser therein. The condenser has an inlet line disposed in flow communication with the drywell for receiving the non-condensable gas along with any steam released therein following a loss-of-coolant accident (LOCA). The condenser also has an outlet line disposed in flow communication with the drywell for returning to the drywell both liquid condensate produced upon cooling of the steam and the non-condensable gas for reducing pressure within the containment vessel following the LOCA. 1 figure.

Billig, P.F.; Cooke, F.E.; Fitch, J.R.

1994-01-25

285

Small passive chemical detector  

SciTech Connect

A novel technique has been developed for the detection of organic compounds in the environment. These detectors are passive'' in the sense that they do not contain any electronic or mechanical instrumentation. A visual color change of the devices after exposure to the target compounds of interest allows a quick identification and quantitative determination of the targets. The detection mechanism is based on colorimetry and combines two molecular biology techniques, Enzyme Multiplied Immunoassay Technique (EMIT) and Ouchterlony Double Diffusion in Two Dimensions. Preliminary studies have shown that the presence of 2,4-dinitrophenol can be monitored by the formation of the blue colored complexes as a result of the reaction between an enzyme (alkaline phosphatase) and a substrate (5-bromo-4-chloro-3-indolyl phosphate).

Hong, K.C.

1992-03-26

286

Passive containment cooling system  

DOEpatents

A passive containment cooling system includes a containment vessel surrounding a reactor pressure vessel and defining a drywell therein containing a non-condensable gas. An enclosed wetwell pool is disposed inside the containment vessel, and a gravity driven cooling system (GDCS) pool is disposed above the wetwell pool in the containment vessel and is vented to the drywell. An isolation pool is disposed above the GDCS pool and includes an isolation condenser therein. The condenser has an inlet line disposed in flow communication with the drywell for receiving the non-condensable gas along with any steam released therein following a loss-of-coolant accident (LOCA). The condenser also has an outlet line disposed in flow communication with the drywell for returning to the drywell both liquid condensate produced upon cooling of the steam and the non-condensable gas for reducing pressure within the containment vessel following the LOCA.

Billig, Paul F. (San Jose, CA); Cooke, Franklin E. (San Jose, CA); Fitch, James R. (San Jose, CA)

1994-01-01

287

Passive seismic experiment  

NASA Technical Reports Server (NTRS)

The design, deployment, and operation of the Apollo 16 passive seismic experiment (PSE) are discussed. Since activation, all elements of the PSE have operated as planned, with the exception of the sensor thermal control system. Significant progress in the measurement of meteoroid flux in near-earth space has been made, along with dilineation of active moonquake source regions. The data obtained indicate that moonquakes are concentrated at great depth (800 to 1000 km) and that the apparent disparity between meteoroid flux estimtes based on lunar crater counts and those from earth-based observations can be resolved by seismic measurements in favor of the lower flux indicated by the crater count method. The results obtained from the PSE are summarized and their significance is discussed in detail.

Latham, G. V.; Ewing, M.; Press, F.; Sutton, G.; Dorman, J.; Nakamura, Y.; Toksoz, N.; Lammlein, D.; Duennebier, F.

1972-01-01

288

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

289

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.

2000-01-27

290

Total Measurement Uncertainty (TMU) for Nondestructive Assay of Transuranic (TRU) Waste at the WRAP Facility  

SciTech Connect

This report examines the contributing factors to NDA measurement uncertainty at WRAP The significance of each factor on the TMU is analyzed and a final method is given for determining the TMU for NDA measurements at WRAP. As more data becomes available and WRAP gains in operational experience this report will be reviewed semi annually and updated as necessary.

WILLS, C.E.

2000-01-06

291

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

Microsoft Academic Search

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.

2000-01-01

292

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

293

The use of TI-208 gamma rays for safeguards, nondestructive-assay (NDA) measurements  

SciTech Connect

This paper examines two cases where gamma rays from Tl-208, including the 2614keV gamma ray, were used to detect anomalies in waste material. In addition to the characterization of waste for waste acceptance, and compliance with environmental and transportation laws, there is a safeguards element as well. The more sophisticated method of NDA at Y-12 includes a means to detect shielded special nuclear material (SNM). Excess count rates in the 2614keV gamma ray from Tl-208 are an indication of potential shielded HEU in waste as well as other containers. The 2614keV gamma ray is easy to monitor routinely. When a large 2614keV peak is detected, further investigation can be conducted from the gamma spectrum. This paper describes this further investigation in two cases. In one case self-shielded HEU was detected. In the other case the Tl-208 gamma rays came from a piece of Th-232 metal.

Oberer, R. B.; Chiang, L. G.; Norris, M. J.; Gunn, C. A.; Adaline, B. C.

2009-05-26

294

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

295

Active source requirements for assay of sludge drums on the BIR WIT system  

SciTech Connect

The design of the active source for active and passive computed tomography (A&PCT) is critical with respect to accuracy and throughput. The A&PCT active source requirements are highly dependent upon the attenuation properties of the waste matrix within the drum. On of the most highly attenuating waste matrices is sludge. This waste stream will consist of solidified aqueous waste consisting of IDC 001 first stage sludge and IDC 007 wet sludge. Also, the stream consists of solidified organic waste known as code IDC 003 organic setups. We have evaluated the sludge drum data that was previously acquired on the WIT system and have determined that the active source activity must be increased to provide reasonable throughput. The sludge drum that is evaluated here is drum CEPRF11. CEPRF11 is a test drum that was part of the Nondestructive Assay system Capability Evaluation Project (CEP) and contained an actual Rocky Flats waste that is categorized as code 003 solidified organic waste. The full drum was evaluated and found to be somewhat homogenous; therefore, a single slice is arbitrarily chosen to represent the entire drum. Slice number 8 is used and is located approximately at the center of the drum. Figure 1 shows the averaged projections for different energies derived from the active sinogram of slice number 8 from the CEPRF11 drum. This is the average of all the projections of slice 8 taken over 180 degrees with an active integration time of 6 seconds. Figure 2 is also a graph showing the average of all the projections for slice 8; however, the active integration time is 30 seconds.

Roberson, G.P.; Camp, D.C.

1998-04-27

296

Tomographic gamma scanning to assay heterogeneous radioactive waste  

SciTech Connect

Current methods for the nondestructive assay of special nuclear materials (SNM) and transuranic (TRU) waste in 208-l drums can give assay errors of 100% or more when the drum matrix and/or radionuclide distribution is nonuniform. This problem is addressed by the development of the tomographic-gamma-scanner (TGS) method for assaying heterogeneous drummed SNM/TRU waste. The TGS method improves on the well-established segmented-gamma-scanner (SGS) method by performing low-resolution tomographic emission and transmission scans on the drum, yielding coarse three-dimensional images of the matrix density and radionuclide distributions. The images are used to make accurate, point-to-point attenuation corrections. The TGS geometric counting efficiency is 60% that of a typical SGS device, allowing a TGS assay time of only 28 min/drum with a one-detector system. The TGS method may also be useful for nondestructive examination. Currently, TGS is the only practical method of imaging SNM in drums.

Estep, R.J.; Prettyman, T.H.; Sheppard, G.A. (Los Alamos National Lab., NM (United States))

1994-11-01

297

Confocal imaging to quantify passive transport across biomimetic lipid membranes.  

PubMed

The ability of a molecule to pass through the plasma membrane without the aid of any active cellular mechanisms is central to that molecule's pharmaceutical characteristics. Passive transport has been understood in the context of Overton's rule, which states that more lipophilic molecules cross membrane lipid bilayers more readily. Existing techniques for measuring passive transport lack reproducibility and are hampered by the presence of an unstirred layer (USL) that dominates transport across the bilayer. This report describes assays based on spinning-disk confocal microscopy (SDCM) of giant unilamellar vesicles (GUVs) that allow for the detailed investigation of passive transport processes and mechanisms. This approach allows the concentration field to be directly observed, allowing membrane permeability to be determined easily from the transient concentration profile data. A series of molecules of increasing hydrophilicity was constructed, and the transport of these molecules into GUVs was observed. The observed permeability trend is consistent with Overton's rule. However, the values measured depart from the simple partition-diffusion proportionality model of passive transport. This technique is easy to implement and has great promise as an approach to measure membrane transport. It is optimally suited to precise quantitative measurements of the dependence of passive transport on membrane properties. PMID:20722391

Li, Su; Hu, Peichi; Malmstadt, Noah

2010-09-15

298

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

299

Nondestructive Evaluation Correlated with Finite Element Analysis  

NASA Technical Reports Server (NTRS)

Advanced materials are being developed for use in high-temperature gas turbine applications. For these new materials to be fully utilized, their deformation properties, their nondestructive evaluation (NDE) quality and material durability, and their creep and fatigue fracture characteristics need to be determined by suitable experiments. The experimental findings must be analyzed, characterized, modeled and translated into constitutive equations for stress analysis and life prediction. Only when these ingredients - together with the appropriate computational tools - are available, can durability analysis be performed in the design stage, long before the component is built. One of the many structural components being evaluated by the NDE group at the NASA Lewis Research Center is the flywheel system. It is being considered as an energy storage device for advanced space vehicles. Such devices offer advantages over electrochemical batteries in situations demanding high power delivery and high energy storage per unit weight. In addition, flywheels have potentially higher efficiency and longer lifetimes with proper motor-generator and rotor design. Flywheels made of fiber-reinforced polymer composite material show great promise for energy applications because of the high energy and power densities that they can achieve along with a burst failure mode that is relatively benign in comparison to those of flywheels made of metallic materials Therefore, to help improve durability and reduce structural uncertainties, we are developing a comprehensive analytical approach to predict the reliability and life of these components under these harsh loading conditions. The combination of NDE and two- and three-dimensional finite element analyses (e.g., stress analyses and fracture mechanics) is expected to set a standardized procedure to accurately assess the applicability of using various composite materials to design a suitable rotor/flywheel assembly.

Abdul-Azid, Ali; Baaklini, George Y.

1999-01-01

300

New passive helicopter detector  

SciTech Connect

Sandia has developed a new helicopter detector. The device relies on the correlation between the acoustic wave from the helicopter and the resulting coupled seismic wave. A significant feature of this approach is that the detector is completely passive; there is no radio frequency radiation. Intended for deployment as a perimeter sensor around a site, the unit offers a low nuisance/false alarm rate and a high probability of detection for a wide range of helicopters. Reliable detection occurs when the target is at high altitude and also very near the earth's surface. Detection ranges start at one kilometer for the small, four-place, civilian helicopter and approach five kilometers for heavier, military types. The system has two parts: a transducer package containing a microphone and a geophone and a digital processor. Development is underway for a model which will be AC powered and well suited to permanent facilities. A prototype unit using a lightweight, battery powered processor is being constructed for rapid-deployment applications. 6 figs.

Elliott, G.R.

1985-01-01

301

Passive thermosiphon solar collector  

SciTech Connect

A passive thermosiphon solar collector was designed, built, installed and tested under this grant. The basic premise was to design a simple system that was economical to build and easy to install as a retrofit to many similar homes in the local community. The module is comprised of a 2X4 frame with a sandwiched insert consisting of a flat black painted aluminum absorber panel and a fiberglass reinforced plastic glazing. This insert is completely sealed from the environment with neoprene seals and rubber silicone sealant. The modules are enclosed in an overall framework of 2X8 material bolted to a concrete reinforced footing and attached to the residence at the top. This framework results in an air chamber behind the absorber panel where the air from the basement enters the chamber at the bottom and exits at the top of the chamber into the house. The air chamber is completely insulated with 5/8 inch polyisocyanurate foil covered foam board. Fabrication is detailed in the Design and Construction section and supplemented with the photo series submitted with the Second Quarter report. The test results indicate this modular concept is a viable solution to conserving our national resources and reducing heating expenses. In this specific experiment, the use of solar energy provided a thirty-five percent reduction in natural gas consumption for this home.

Sullivan, J.W.

1984-01-01

302

Passive Acoustic Vessel Localization  

NASA Astrophysics Data System (ADS)

This thesis investigates the development of a low-cost passive acoustic system for localizing moving vessels to monitor areas where human activities such as fishing, snorkeling and poaching are restricted. The system uses several off-the-shelf sensors with unsynchronized clocks where the Time Difference of Arrival (TDOA) or time delay is extracted by cross-correlation of the signal between paired sensors. The cross-correlation function uses phase correlation or Phase Transform (PHAT) which whitens the cross-spectrum in order to de-emphasize dominant frequency components. Using the locations of pairs of sensors as foci, hyperbolic equations can be defined using the time delay between them. With three or more sensors, multiple hyperbolic functions can be calculated which intersect at a unique point: the boat's location. It is also found that increasing separation distances between sensors decreased the correlation between the signals. However larger separation distances have better localization capability than with small distances. Experimental results from the Columbia and Willamette Rivers are presented to demonstrate performance.

Suwal, Pasang Sherpa

303

Passive blast pressure sensor  

SciTech Connect

A passive blast pressure sensor for detecting blast overpressures of at least a predetermined minimum threshold pressure. The blast pressure sensor includes a piston-cylinder arrangement with one end of the piston having a detection surface exposed to a blast event monitored medium through one end of the cylinder and the other end of the piston having a striker surface positioned to impact a contact stress sensitive film that is positioned against a strike surface of a rigid body, such as a backing plate. The contact stress sensitive film is of a type which changes color in response to at least a predetermined minimum contact stress which is defined as a product of the predetermined minimum threshold pressure and an amplification factor of the piston. In this manner, a color change in the film arising from impact of the piston accelerated by a blast event provides visual indication that a blast overpressure encountered from the blast event was not less than the predetermined minimum threshold pressure.

King, Michael J.; Sanchez, Roberto J.; Moss, William C.

2013-03-19

304

Non-destructive measurement of solid plutonium waste at Los Alamos National Laboratory  

SciTech Connect

Los Alamos National Laboratory (LANL) is a national defense facility involved in the recovery and processing of plutonium. Wastes and residues are routinely generated here from many stages of plutonium metal fabrication and from pyrochemical and aqueous processing of plutonium scrap. Materials which require measurement include plutonium oxide from burned residues, Pu-bearing salts from production/reduction and metal purification processes, impure plutonium metal, metal reduction slags, ash, undissolved oxide heels, ceramics, and auxiliary implements such as HEPA filters, plastics, and cleaning rags. Nondestructive assays (NDA) of transuranic (TRU) waste from these materials are often troublesome and may pose formidable challenges to the measurement specialist. This document discusses these waste measurement issues at LANL. 25 figs., 2 tabs.

Wachter, J.R. (Los Alamos National Lab., NM (USA))

1989-01-01

305

Nondestructive detection of hidden chemical compounds with laser Compton-scattering gamma rays  

NASA Astrophysics Data System (ADS)

A nondestructive assay method for measuring a shielded chemical compound has been proposed. The chemical compound is measured by using a nuclear resonance fluorescence (NRF) measurement technique with an energy tunable laser Compton-scattering (LCS) ?-ray source. This method has an advantage that hidden materials can be detected through heavy shields such as iron plates of a thickness of several centimeters. A detection of a chemical compound of melamine, C3H6N6, shielded by 15-mm-thick iron and 4-mm-thick lead plates is demonstrated. The NRF ?-rays of 12C and 14N of the melamine are measured by using the LCS ?-rays of the energies of up to 5.0 MeV. The observed ratio (12C/14N)exp=0.39+/-0.12 is consistent with (C/N)melamine=0.5.

Hayakawa, Takehito; Ohgaki, Hideaki; Shizuma, Toshiyuki; Hajima, Ryoichi; Kikuzawa, Nobuhiro; Minehara, Eisuke; Kii, Toshiteru; Toyokawa, Hiroyuki

2009-04-01

306

Nondestructive detection of hidden chemical compounds with laser Compton-scattering gamma rays.  

PubMed

A nondestructive assay method for measuring a shielded chemical compound has been proposed. The chemical compound is measured by using a nuclear resonance fluorescence (NRF) measurement technique with an energy tunable laser Compton-scattering (LCS) gamma-ray source. This method has an advantage that hidden materials can be detected through heavy shields such as iron plates of a thickness of several centimeters. A detection of a chemical compound of melamine, C(3)H(6)N(6), shielded by 15-mm-thick iron and 4-mm-thick lead plates is demonstrated. The NRF gamma-rays of (12)C and (14)N of the melamine are measured by using the LCS gamma-rays of the energies of up to 5.0 MeV. The observed ratio ((12)C/(14)N)(exp)=0.39+/-0.12 is consistent with (C/N)(melamine)=0.5. PMID:19405694

Hayakawa, Takehito; Ohgaki, Hideaki; Shizuma, Toshiyuki; Hajima, Ryoichi; Kikuzawa, Nobuhiro; Minehara, Eisuke; Kii, Toshiteru; Toyokawa, Hiroyuki

2009-04-01

307

Airborne Passive Target Motion Analysis.  

National Technical Information Service (NTIS)

Kalman filtering techniques are applied to a two sensor bearings only passive target motion analysis problem. An algorithm is developed to simulate tracking long range maneuvering airborne targets. The target tracking performance of the filter is evaluate...

J. A. Gutzler

1987-01-01

308

Enhanced Passive Thermal Propulsion System.  

National Technical Information Service (NTIS)

The long term goal is to advance our understanding of thermal energy extraction from the ocean thermocline using an enhanced passive thermal propulsion system. Integration of this new propulsion technology in a low drag hydrodynamic shape is expected to y...

D. Warner E. Warner

2008-01-01

309

Passive Explosion Barrier for Mines.  

National Technical Information Service (NTIS)

A passive explosion barrier is provided for use in mining operations in suppressing mine explosions. The barrier basically comprises a receptacle or tub which contains an explosion suppressing substance, such as water, and is mounted on a frame adjacent t...

I. Liebman R. Pro J. Corry

1979-01-01

310

Passive Scanning in Modbus Networks  

Microsoft Academic Search

This paper describes the design and implementation of a passive scanner for Modbus networks. The tool integrates packet parsing\\u000a and passive scanning functionality to interpret Modbus transactions and provide accurate network representations. In particular,\\u000a the scanner monitors Modbus messages to maintain and update state table entries associated with field devices. Entries in\\u000a the state tables record important information including function

Jesús González; Mauricio Papa

2007-01-01

311

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

312

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

313

A particle swarm optimizer with passive congregation  

Microsoft Academic Search

This paper presents a particle swarm optimizer (PSO) with passive congregation to improve the performance of standard PSO (SPSO). Passive congregation is an important biological force preserving swarm integrity. By introducing passive congregation to PSO, information can be transferred among individuals of the swarm. A particle swarm optimizer with passive congregation (PSOPC) is tested with a set of 10 benchmark

S. He; Q. H. Wu; J. Y. Wen; J. R. Saunders; R. C. Paton

2004-01-01

314

Nondestructive dynamic detectors for Bose-Einstein condensates  

NASA Astrophysics Data System (ADS)

We propose and analyze a series of nondestructive dynamic detectors for Bose-Einstein condensates based on photodetectors operating at the shot-noise limit. These detectors are compatible with real-time feedback to the condensate. The signal-to-noise ratio of different detection schemes are compared subject to the constraint of minimal heating due to photon absorption and spontaneous emission. This constraint leads to different optimal operating points for interference-based schemes. We find the somewhat counterintuitive result that without the presence of a cavity, interferometry causes as much destruction as absorption for optically thin clouds. For optically thick clouds, cavity-free interferometry is superior to absorption, but it still cannot be made arbitrarily nondestructive. We propose a cavity-based measurement of atomic density which can in principle be made arbitrarily nondestructive for a given signal-to-noise ratio.

Lye, J. E.; Hope, J. J.; Close, J. D.

2003-04-01

315

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

316

Nondestructive identification of cold and extremely localized single molecular ions.  

PubMed

We demonstrate a simple and nondestructive method for identification of a single molecular ion sympathetically cooled by a single laser cooled atomic ion in a linear Paul trap. The technique is based on a precise nondestructive determination of the molecular ion mass through a measurement of the eigenfrequency of a common motional mode of the two ions. The demonstrated mass resolution is sufficiently high that molecular ion mass doublets can potentially be distinguished from each other. The obtained results represent an important step towards single molecule gas phase chemical physics. PMID:15697806

Drewsen, M; Mortensen, A; Martinussen, R; Staanum, P; Sørensen, J L

2004-12-10

317

Maintaining the Constant Exposure Condition for an Acute Caenorhabditis elegans Mortality Test Using Passive Dosing  

PubMed Central

Objectives Maintaining the constant exposure to hydrophobic organic compouds in acute toxicity tests is one of the most difficult issues in the evaluation of their toxicity and corresponding risks. Passive dosing is an emerging tool to keep constant aqueous concentration because of the overwhelming mass loaded in the dosing phase. The primary objectives of this study were to develop the constant exposure condition for an acute mortality test and to compare the performance of the passive dosing method with the conventional spiking with co-solvent. Methods A custom cut polydimethylsiloxane (PDMS) tubing loaded with benzyl butyl phthalate (BBP) was placed in each well of a 24-well plate containing assay medium. The rate of the release of BBP from PDMS was evaluated by measuring the change in the concentration of BBP in the assay medium. The efficiency of maintaining constant exposure condition was also evaluated using a simple two-compartment mass transport model employing a film-diffusion theory. An acute mortality test using 10 C. elegans in each well was conducted for the evaluation of the validity of passive dosing and the comparative evaluation of the passive dosing method and the conventional spiking method. Results Free concentration in the assay medium reached 95% steady state value within 2.2 hours without test organisms, indicating that this passive dosing method is useful for an acute toxicity test in 24 hours. The measured concentration after the mortality test agreed well with the estimated values from partitioning between PDMS and the assay medium. However, the difference between the nominal and the free concentration became larger as the spiked concentration approached water solubility, indicating the instability of the conventional spiking with a co-solvent. Conclusions The results in this study support that passive dosing provides a stable exposure condition for an acute toxicity test. Thus, it is likely that more reliable toxicity assessment can be made for hydrophobic chemicals using passive dosing.

Kwon, Hyuck-Chul; Roh, Ji-Yeon; Lim, Dongyoung; Choi, Jinhee

2011-01-01

318

Nondestructive Magnetic Testing of Laser Hardening Parameters (Hardening Depth, Hardness Profile, Retained Austenite). Final Report.  

National Technical Information Service (NTIS)

Because of the increasing commercial use of high power lasers for surface annealing treatments, a nondestructive test to improve the production quality and reliability is required. Therefore our aim is the development of a nondestructive testing method to...

R. Kern W. Theiner

1986-01-01

319

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

320

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

321

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

322

CMR Shuffler System: Passive Mode Calibration and Certification Report  

SciTech Connect

Los Alamos National Laboratory has a number of spherical confinement vessels (CVs) remaining from tests involving nuclear materials. These vessels have an inner diameter of 6 feet with 1 to 2 inch thick steel walls. The goal of the Confinement Vessel Disposition (CVD) project is to remove debris and reduce contamination inside the vessels. As debris is removed from the vessels, material will be placed in waste drums. Far-field gamma ray assay will be used to determine when a drum is nearing a {sup 239}Pu equivalent mass of less than 200 g. The drum will then be assayed using a waste drum shuffler operated in passive mode using a neutron coincidence counting method for accountability. This report focuses on the testing and calibration of the CMR waste drum shuffler in passive mode operation. Initial testing was performed to confirm previously accepted measurement parameters. The system was then calibrated using a set of weapons grade Pu (WGPu, {sup 239}Pu > 93%) oxide standards placed inside a 55 gallon drum. The calibration data ranges from Pu mass of 0.5 g to 188.9 g. The CMR waste drum shuffler has been tested and calibrated in passive mode in preparation for safeguards accountability measurements of waste drums containing material removed from CVs for the CVD project.

Frame, Katherine C. [Los Alamos National Laboratory; Gomez, Cipriano D. [Retired CMR-OPS: OPERATIONS; Salazar, William R. [Los Alamos National Laboratory; Mayo, Douglas R. [Los Alamos National Laboratory; Vigil, Georgiana M. [Los Alamos National Laboratory; Crooks, William J. [Los Alamos National Laboratory; Stange, Sy [Los Alamos National Laboratory

2012-07-20

323

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

324

Materials for passively safe reactors  

SciTech Connect

Future nuclear power capacity will be based on reactor designs that include passive safety features if recent progress in advanced nuclear power developments is realized. There is a high potential for nuclear systems that are smaller and easier to operate than the current generation of reactors, especially when passive or intrinsic characteristics are applied to provide inherent stability of the chain reaction and to minimize the burden on equipment and operating personnel. Taylor, has listed the following common generic technical features as the most important goals for the principal reactor development systems: passive stability, simplification, ruggedness, case of operation, and modularity. Economic competitiveness also depends on standardization and assurance of licensing. The performance of passively safe reactors will be greatly influenced by the successful development of advanced fuels and materials that will provide lower fuel-cycle costs. A dozen new designs of advanced power reactors have been described recently, covering a wide spectrum of reactor types, including pressurized water reactors, boiling water reactors, heavy-water reactors, modular high-temperature gas-cooled reactors (MHTGRs), and fast breeder reactors. These new designs address the need for passive safety features as well as the requirement of economic competitiveness.

Simnad, T. (Univ. of California, San Diego, (United States))

1993-01-01

325

Nondestructive Evaluation and Inspection Programs for Pershing II Motors.  

National Technical Information Service (NTIS)

Quality control inspection of Pershing II (P-II) solid-propellant rocket motors was historically the responsibility of the manufacturer. Now the U.S. Army Pueblo Depot Activity (PDA) has been assigned the task of nondestructive evaluation and inspection (...

F. W. Kearney M. D. Ginsberg R. B. Moler

1990-01-01

326

Neutron radiographic nondestructive inspection for bonded composite structures  

Microsoft Academic Search

Neutron radiography was found to be effective as a nondestructive inspection technique for detection of bondline voids\\/defects in a variety of composite structures. Radiographic data are presented from typical structures for which the neutron radiographic inspection technique offers advantages over more conventional inspection techniques. Complex composite joints such as box beam members, for example, are difficult to inspect by ultrasonic

W. E. Dance; J. B. Middlebrook

1979-01-01

327

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

328

Non-Destructive Testing of Wisconsin Highway Bridges.  

National Technical Information Service (NTIS)

The management of in-service bridges throughout the United States is an important task. An effective assessment of the condition of these bridges is an essential requirement for this task. Non-destructive evaluation can be an effective tool in the inspect...

A. Ghorbanpoor N. Benish

2003-01-01

329

Infrared Nondestructive Analysis of Solid Rubber Road Wheels.  

National Technical Information Service (NTIS)

Twenty-six used and rebuilt solid rubber road wheels were examined by an infrared temperature profiling technique during drum test exercise. The IR method was evaluated as a nondestructive means of predicting road wheel integrity by analysis of the circum...

D. K. Wilburn

1973-01-01

330

Development of nondestructive evaluation methods for structural ceramics.  

National Technical Information Service (NTIS)

During the past year, the focus of our work on nondestructive evaluation (NDE) methods was on the development and application of these methods to technologies such as ceramic matrix composite (CMC) hot-gas filters, CMC high-temperature heat exchangers, an...

W. A. Ellingson

1998-01-01

331

SQUID-based nondestructive evaluation of carbon fiber reinforced polymer  

Microsoft Academic Search

Recent work with HTS SQUIDs in nondestructive evaluation has concentrated on the detection of flaws in aircraft-grade aluminum, with particular emphasis on surface-breaking tears beside rivets. More complex materials are now also being used in aircraft manufacture, with carbon fiber reinforced polymer (CFRP) being one of the most common. Existing technologies such as ultrasound are particularly well suited to the

C. Carr; D. Graham; J. C. Macfarlane; G. B. Donaldson

2003-01-01

332

NON-DESTRUCTIVE ANALYSIS OF SHIELDED HIGHLY ENRICHED URANIUM  

Microsoft Academic Search

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

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

2001-01-01

333

Nondestructive determination of welding residual stresses by boundary element method  

Microsoft Academic Search

A nondestructive procedure was proposed in the paper to determine the welding residual stresses with the aid of the boundary integral equation and its discrete form—the boundary element method, in which the displacements measured at the boundaries or the welding deformations of the welded structures were taken as the known boundary conditions. Its feasibility was verified in two-dimensional cases, by

H. Ma; H. L. Deng

1998-01-01

334

Proceedings of the 5. Pan Pacific conference on nondestructive testing.  

National Technical Information Service (NTIS)

This is the fifth in the series of Pan Pacific Conference on Nondestructive Testing held once every two years. The honour of hosting the conference is shared among those countries bordering on the Pacific Ocean, this year the responsibility being granted ...

C. A. Kittmer

1987-01-01

335

Elastic Wave Propagation and Nondestructive Evaluation of Materials  

Microsoft Academic Search

ABSTRACT The use of elastic waves to measure elastic properties as well as flaws in solid specimens,has received much attention, and many important applications have been developed recently. This paper summarizes some,of the ,recent results in applying ,elastic waves ,to nondestructive evaluation ,(NDE) of isotropic ,as well as anisotropic materials. This paper is divided into four parts, the first part

Tsung-tsong Wu

336

Nondestructive examination of welds through painted surfaces: Final report  

Microsoft Academic Search

A study was performed to develop reliable nondestructive examination techniques for detection of surface-open defects located under a surface coating on ferromagnetic materials. The magnetic particle test method (MT) alternating current (ac) yoke technique presently appears to be an optimum approach because of its technically straight-forward operational basis. A complementary technique uses the eddy current method with a differential type

J. F. Cook; J. A. Holm; G. D. Lassahn

1988-01-01

337

Characterization of Adhesive Layers in Sandwich Composites by Nondestructive Technique  

Microsoft Academic Search

New nondestructive technique, namely an inverse technique based on vibration tests, to characterize nonlinear mechanical properties of adhesive layers in sandwich composites is developed. An adhesive layer is described as a viscoelastic isotropic material with storage and loss moduli which are both frequency dependent values in wide frequency range. An optimization based on the planning of experiments and response surface

E. Barkanov; M. Wesolowski; A. Chate

2009-01-01

338

Development of nondestructive evaluation methods for ceramic coatings..  

National Technical Information Service (NTIS)

Various nondestructive evaluation (NDE) technologies are being developed to study the use of ceramic coatings on components in the hot-gas path of advanced low-emission gas-fired turbines. The types of ceramic coatings include thermal barrier coatings (TB...

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

2002-01-01

339

Nondestructive testing methods for 55-gallon, waste storage drums  

Microsoft Academic Search

The Westinghouse Hanford Company (WHC) authorized Pacific Northwest Laboratory (PNL) to conduct a feasibility study to identify promising nondestructive testing (NDT) methods for detecting general and localized (both pitting and pinhole) corrosion in the 55-gal drums that are used to store solid waste materials at the Hanford Site. This document presents results obtained during a literature survey, identifies the relevant

R. H. Ferris; B. P. Hildebrand; R. L. Hockey; D. M. Riechers; J. C. Spanner; D. R. Duncan

1993-01-01

340

Dual-band infrared thermography for quantitative nondestructive evaluation  

Microsoft Academic Search

The authors have developed dual-band infrared (DBIR) thermography that is being applied to quantitative nondestructive evaluation (NDE) of aging aircraft. The DBIR technique resolves 0.2 degrees C surface temperature differences for inspecting interior flaws in heated aircraft structures. It locates cracks, corrosion sites, disbonds or delaminations in metallic laps and composite patches. By removing clutter from surface roughness effects, the

P. F. Durbin; N. K. Del Grande; K. W. Dolan; D. E. Perkins; A. B. Shapiro

1993-01-01

341

Nondestructive Technique for Assessing Field SEAM Quality of Prefabricated Geomembranes.  

National Technical Information Service (NTIS)

Research was conducted to test various nondestructive testing (NDT) methods that are or can be used to assess the quality of field seams in synthetic geomembranes. The objective of the work was to find a universally applicable technique and demonstrate it...

G. E. Spanner

1984-01-01

342

Nondestructive indices of trace element exposure in squamate reptiles  

Microsoft Academic Search

Compared with birds, mammals, fish, and even amphibians, very little is known about the effects of contaminants on reptiles. Recent evidence that many reptile populations may be declining has stimulated demand for toxicological studies of reptiles as well as development of nondestructive sampling techniques useful for assessing and monitoring contaminant exposure. The current study experimentally evaluated the utility of shed

W. A. Hopkins; J. H. Roe; J. W. Snodgrass; B. P. Jackson; D. E Kling; C. L. Rowe; J. D. Congdon

2001-01-01

343

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

344

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

345

A nondestructive method for continuously monitoring plant growth  

NASA Technical Reports Server (NTRS)

In the past, plant growth generally has been measured using destructive methods. This paper describes a nondestructive technique for continuously monitoring plant growth. The technique provides a means of directly and accurately measuring plant growth over both short and long time intervals. Application of this technique to the direct measurement of plant growth rates is illustrated using corn (Zea mays L.) as an example.

Schwartzkopf, S. H.

1985-01-01

346

Nondestructive evaluation of aircraft composites using terahertz time domain spectroscopy  

Microsoft Academic Search

Terahertz time domain spectroscopy was used for nondestructive evaluation of aircraft glass fiber composites stressed with bending and heating damage. Refractive index and absorption coefficients were measured for both damaged and undamaged composites. The two dimensional extent of the heat damage could be shown with either a simple phase or amplitude terahertz imaging technique.

Christopher D. Stoik; Matthew J. Bohn; James L. Blackshire

2008-01-01

347

Nondestructive evaluation of aircraft composites using terahertz time domain spectroscopy  

Microsoft Academic Search

Terahertz (THz) time domain spectroscopy (TDS) was assessed as a nondestructive evaluation technique for aircraft composites. Material properties of glass fiber composite were measured using both transmission and reflection configuration. The interaction of THz with a glass fiber composite was then analyzed, including the effects of scattering, absorption, and the index of refraction, as well as effective medium approximations. THz

Christopher D. Stoik

2008-01-01

348

Nondestructive evaluation of repairs on aircraft composite structures  

Microsoft Academic Search

Composite sandwiches have been used widely in flight controls of aircraft for many years; solid laminates have also begun to appear in primary structures such as the empennage. In their normal service life, composite parts may suffer damages and require repair and post-repair inspection. Nondestructive inspection is also needed for many of the rebuilt and refurbished parts in the maintenance,

David K. Hsu; Daniel J. Barnard; John J. Peters

2001-01-01

349

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

350

Non-destructive testing of semiconductors using surface acoustic wave  

Microsoft Academic Search

The major emphasis of this report is on a new and novel surface acoustic wave (SAW) device which has been developed under this grant for use in the nondestructive determination of the electronic properties of semiconductors. The technique uses surface acoustic waves on a piezoelectric substrate. The electric field associated with the SAW interacts with free carriers of a semiconductor

B. Davari; P. Das

1983-01-01

351

Acoustic emission - A diagnostic tool in non-destructive testing  

Microsoft Academic Search

Acoustic or stress wave emission is exemplified by the familiar 'cry of tin', an audible noise which is attributed to crystal twinning. This emission attracts currently a great deal of attention in nondestructive testing. On subjecting a nonhomogeneous material to loading stress, the stress field and the material will both vary from point to point, so that local unstable conditions

R. W. B. Stephens; H. C. Kim

1982-01-01

352

Enhancing quality control in transportation construction through nondestructive testing  

Microsoft Academic Search

This paper addresses the growing need for modern nondestructive evaluation (NDE) techniques for quality control during the construction\\/fabrication stages of transportation infrastructure. While the use of NDE techniques for in-service monitoring of infrastructure is increasing, very little effort is currently being made to use NDE for construction quality control. This paper proposes the use of modern NDE techniques for inspection

Udaya B. Halabe; David R. Martinelli; Samer H. Petro

1999-01-01

353

Is Fecal Diversion Necessary for Nondestructive Penetrating Extraperitoneal Rectal Injuries?  

Microsoft Academic Search

Background: Current management of penetrating extraperitoneal rectal injury in- cludes diversion of the fecal stream. The purpose of this study is to assess whether nondestructive penetrating extraperitoneal rectal injuries can be managed successfully without diversion of the fecal stream. Methods: This study was performed at an urban Level I trauma center during a 28-month period from February 2003 through June

Richard P. Gonzalez; Herbert Phelan; Moustaffa Hassan; C. Neal Ellis; Charles B. Rodning

2006-01-01

354

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

355

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) [Pleasanton, CA; Snyderman, Neal J. (Berkeley, CA) [Berkeley, CA; Rowland, Mark S. (Alamo, CA) [Alamo, CA

2010-07-13

356

Factor XII assay  

MedlinePLUS

Hageman factor assay ... test if a family member was diagnosed with factor XII deficiency. ... Decreased factor XII activity may indicate: Inherited (congenital) deficiency of factor XII Liver disease

357

Passive wireless ultrasonic transducer systems  

NASA Astrophysics Data System (ADS)

Inductive coupling and capacitive coupling both offer simple solutions to wirelessly probe ultrasonic transducers. This paper investigates the theory and feasibility of such system in the context of non-destructive evaluation (NDE) applications. Firstly, the physical principles and construction of an inductively coupled transducer system (ICTS) and a capacitively coupled transducer system (CCTS) are introduced. Then the development of a transmission line model with the measured impedance of a bonded piezoelectric ceramic disc representing a sensor attached to an arbitrary solid substrate for both systems is described. The models are validated experimentally. Several applications of CCTS are presented, such CCTS for the underwater and through-composite testing.

Zhong, C. H.; Croxford, A. J.; Wilcox, P. D.

2014-02-01

358

Some Hazards of Passive Smoking  

PubMed Central

Non-smokers are exposed to three types of cigaret smoke: mainstream, sidestream and diffusional smoke, of which sidestream (produced while the cigaret smolders in an ashtray) is the most toxic. Studies of passive smoking show that while smoke is an unpleasant irritant, it appears to have no lasting effects on healthy passive smokers. It may, however, be a particular irritant to already sensitive individuals such as asthmatics, and to young children chronically exposed. Such children show an increase of respiratory disorders, and adults show an increase of small airway disease with a possible risk of lung cancer. More stringent legislation on smoking is desirable.

Shephard, Roy J.

1982-01-01

359

Indoor localization using passive RFID  

NASA Astrophysics Data System (ADS)

Radio frequency identification (RFID) systems based on passive tags are used successfully in a wide range of object identification applications. However, the increasing needs to meet new demands on applications of localization and tracking create a new field for evolution of the RFID technology. This paper presents the design, implementation, and evaluation of a cost-effective localization system for in-building usage that is able to localize objects that carry passive RFID tags. The RFID reading is performed by a single Reader and an array of directional antennas through multiplexing. Evaluation and experimental results from three localization algorithms based on RSSI are presented.

Vastianos, George E.; Kyriazanos, Dimitris M.; Segou, Olga E.; Mitilineos, Stelios A.; Thomopoulos, Stelios C. A.

2011-05-01

360

Passivation of high temperature superconductors  

NASA Technical Reports Server (NTRS)

The surface of high temperature superconductors such as YBa2Cu3O(7-x) are passivated by reacting the native Y, Ba and Cu metal ions with an anion such as sulfate or oxalate to form a surface film that is impervious to water and has a solubility in water of no more than 10(exp -3) M. The passivating treatment is preferably conducted by immersing the surface in dilute aqueous acid solution since more soluble species dissolve into the solution. The treatment does not degrade the superconducting properties of the bulk material.

Vasquez, Richard P. (inventor)

1991-01-01

361

Passive tracking with sensors of opportunity using passive coherent location  

Microsoft Academic Search

Passive coherent location (PCL), which uses the commercial signals as illuminators of opportunity, is an emerging technology in air defense systems. The advantages of PCL are low cost, low vulnerability to electronic counter measures, early detection of stealthy targets and low-altitude detection. However, limitations of PCL include lack of control over illuminators, poor bearing accuracy, time-varying sensor parameters and limited

Mahes Subramaniam; R. Tharmarasa; Mike McDonald; T. Kirubarajan

2008-01-01

362

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

363

Uremia Toxin Assay.  

National Technical Information Service (NTIS)

The purpose of the research was to find assay systems which could be used in attempts to isolate the supposed toxins of uremia. A total of 14 enzyme assay systems were tested against fractions of plasma, dialysate, and urine from both uremic subjects unde...

C. E. Cook

1970-01-01

364

Analyte detection assay  

US Patent & Trademark Office Database

A rapid and sensitive analyte detection assay is based on whispering gallery modes of fluorescently labelled microspheroidal particles. Ligands for the analyte, such as nucleic acids, are anchored to the particles. The fluorescent labels may comprise fluorophores or quantum dots. In the latter case, the particles may comprise melamine formaldehyde. The assay may be used to detect analytes in aqueous samples.

2013-12-31

365

Single-cell assays  

PubMed Central

This review presents an overview of literature that describes the applications of microfluidics to assay individual cells. We quantify the content of an individual mammalian cell, so that we can understand what criteria a single-cell assay must satisfy to be successful. We put in context the justification for single-cell assays and identify the characteristics that are relevant to single-cell assays. We review the literature from the past 24 months that describe the methods that use microfabrication—conventional or otherwise—and microfluidics in particular to study individual cells, and we present our views on how an increasing emphasis on three-dimensional cell culture and the demonstration of the first chemically defined cell might impact single-cell assays.

Ryan, Declan; Ren, Kangning; Wu, Hongkai

2011-01-01

366

Passive Optical Bathymetry with CAESAR.  

National Technical Information Service (NTIS)

In addition to experiments with passive optical bathymetry with Landsat-TM a new project 'CAESAR-bottom' has been started. Its main objective is to compare the accuracy of the estimated depth of CAESAR with those of Landsat-TM. If possible the method of d...

M. van der Laan

1991-01-01

367

Passive Parallel Automatic Minimalist Processing  

Microsoft Academic Search

Research for which the idea that many basic cognitive processes can be described as fast, parallel, and automatic is reviewed. Memory retrieval\\/decision processes have often been ignored in the cognitive literature. However, in some cases, computation- ally complex processes can be replaced with simple passive processes. Cue-dependent retrieval from memory provides a straightforward example of how encoding, memory, and retrieval

Roger Ratcliff; Gail McKoon

368

Passive oscillatory heat transport systems  

Microsoft Academic Search

An underdeveloped class of oscillatory passive heat transport cycles are discussed that have the potential to transport significantly higher heat loads than current heat pipes. Prototype cycles employing inferior working fluids have demonstrated transport of higher heat loads over significantly greater distances than similarly sized heat pipes (including CPLs and LHPs) employing ammonia. Most of the proposed cycles do not

Mark M. Weislogel

2002-01-01

369

Orion Passive Thermal Control Overview  

NASA Technical Reports Server (NTRS)

An viewgraph presentation of Orion's passive thermal control system is shown. The topics include: 1) Orion in CxP Hierarchy; 2) General Orion Description/Orientation; 3) Module Descriptions and Images; 4) Orion PTCS Overview; 5) Requirements/Interfaces; 6) Design Reference Missions; 7) Natural Environments; 8) Thermal Models; 9) Challenges/Issues; and 10) Testing

Miller, Stephen W.

2007-01-01

370

Passive Shimming for Solenoidal Magnets.  

National Technical Information Service (NTIS)

The report shows how passive iron shims may be used to correct the field of a nearly uniform solenoidal magnet. From the theory which is developed in the appendices, it is shown that thin shell-like shims are preferred for a large volume of corrected fiel...

J. H. Coupland

1986-01-01

371

Adaptive passive velocity field control  

Microsoft Academic Search

Passive velocity field control (PVFC) was previously developed for mechanical systems which have strong coordination and must interact with the physical environment. Applications include teleoperated manipulators, contouring in machining and smart exercise machines. The methodology encodes tasks using time invariant desired velocity fields instead of the more traditional method of timed trajectories and guarantees that the closed loop system behave

Perry Y. Li; Minneapolis MN

1999-01-01

372

Robust Passive Piezoelectric Shunt Dampener  

Microsoft Academic Search

This paper introduces a new multiple mode passive piezoelectric shunt damping technique. The robust pas- sive piezoelectric shunt controller is capable of damping multiple structural modes and maybe less susceptible to variations in environmental conditions that can severely eect the performance of other controllers. The proposed control scheme is validated experimentally on a piezoelectric laminated plate structure.

S. Behrens; A. J. Fleming; S. O. R. Moheimani

373

[Passive smoking--active killer].  

PubMed

Although still not perceived in this way, passive smoking is a public health issue of great importance. World Health Organization estimates that as a result of passive exposure to tobacco smoke each year 600,000 people die, of which 165,000 children. There are 33% of men, 35% of women and 40% of children who do not smoke, but are exposed to second hand smoke, and still only 11% of the world population is protected by adequate smoke-free legislation. Scientific literature provides evidence that passive exposure to tobacco smoke can result in numerous adverse health effects: asthma and allergies, respiratory infections and (middle) ear infections, cancers of various localization, accelerated atherosclerosis and cardiovascular diseases, retardation of growth and development in children, and in pregnancy it can lead to congenital anomalies and premature birth as well as lower body weight and length of the child. Certainly, the scariest consequence of all is sudden infant death syndrome, also called "death in the crib". Smoke-free policies have proven their effectiveness, but while implementing the laws, it is necessary to raise public awareness of the hazards of, both active and passive, exposure to tobacco smoke. PMID:24490334

Palavra, Irena Rojni?; Franeli?, Iva Pejnovi?; Milanovi?, Sanja Musi?; Pulji?, Kresimir

2013-01-01

374

Passive maser development at NRL  

SciTech Connect

The application of passive hydrogen masers to satellites was investigated. The NRL maser is of compact design suitable for the space environment. It is based on a dielectrically loaded sapphire cavity and uses a computer optimized set of four shields. The servo design is a phase sensitive method which directly measures the phase dispersion of the interrogating signal as it passes through the cavity.

White, J.D.; Frank, A.; Folen, V.

1981-01-01

375

Passive solar, country-style  

SciTech Connect

This article describes a 2170 ft{sup 2} (202 m{sup 2}) custom-designed passive solar home in rural Burlington, North Carolina. The architectural style elegantly combines pleasing aesthetics with practical attention to energy conservation. Included in the article are details of the construction, energy efficient materials and design, energy performance, cost performance.

Miller, B.

1996-07-01

376

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

377

Interior Design for Passive Solar Homes.  

National Technical Information Service (NTIS)

The increasing emphasis on refinement of passive solar systems has brought recognition to interior design as an integral part of passive solar architecture. Interior design can be used as a finetuning tool minimizing many of the problems associated with p...

J. C. Breen

1981-01-01

378

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

379

Mapping the Whole Internet with Passive Measurements.  

National Technical Information Service (NTIS)

This final technical report describes an effort to develop a comprehensive and accurate map of the Internet using passive measurements, diverse data sets and statistical learning methods. The effort passively collected a comprehensive set of Internet traf...

B. Maggs

2012-01-01

380

Non-destructive investigations at the Dionisiac Frieze in the Villa of Mysteries, Pompeii  

NASA Astrophysics Data System (ADS)

The Villa of Mysteries with its Dionisiac Frieze is one of the well-known buildings of ancient Pompeii. It has been excavated in the early 20th century. Since then many initiatives have been taken for its preservation. Currently, the Frieze is investigated in detail and tests have been made to clean the wall paintings. Non-destructive investigations as infrared thermography (IR), Ground penetrating radar (GPR), and ultrasonic measurements have been performed in order to test if these methods are well suited to reveal the walls' and paintings' structure and to identify the detachments or cracks. IR, GPR and ultrasonic measurements have different penetration capabilities and resolution in depths. So, using these three methods simultaneously can improve the knowledge of the investigated structures at several depths from millimetres and centimetres to metres. It has been tested if detachments of the paintings, cracks, or alterations of the paintings can be detected by passive and active IR measurements. 6 passive and 3 active measurements have been conducted on the Dionisiac Frieze. Lateral temperature differences present at the Frieze are mapped by passive measurements. Here, we show that temperature differences up to about 0.3°C are present and detectable. These small changes in temperature may be related to detachments, cracks, or wet areas. By active IR measurements the paintings are artificially heated by about 1°C and the cooling to normal temperature is observed and analyzed. Lateral differences in the heating and cooling behavior are related to variability in the heat absorption properties and in thermal conductivity. It is shown that detachments as well as restorative treatments are associated with changes in the thermal behavior. In order to image the construction and the condition of the investigated walls, Ground Penetrating Radar (GPR) was measured with a 2 GHz antenna. Each profile was 1.2 m long, the spacing cross-line was 3 cm and in-line 1 mm. The vertical sections contain reflection horizons of the plaster layer, the second wall layer and the back wall. Additional diffractions of objects with high differences in electrical properties i.e. bricks, cavities, cracks enables to estimate the travelling velocity of electromagnetic waves and the deep penetration. In addition, calculated time slices show areas with concentrated high and low reflection energy of different depth layers of the wall inside structure, which can related to changes in the composition and the water saturation. Ultrasonic experiments with frequencies between about 5 kHz and 500 kHz may be applied to non-destructive testing of structures made of natural stone for example facades, engineering structures, Usually, traveltimes of first-arriving P-waves are measured in ultrasonic transmission experiments. The resolution for changes of uppermost structures in transmission configuration is however limited. Therefore, we firstly perform surface measurements and secondly the full waveform is investigated. That means source and receiver are coupled to nearly plane parts of the object's surface and the receiver is moved along profiles with lengths between about 10 cm to 30 cm. These measurements are simple to perform because the object under consideration has to be accessible only from one side and the source and receiver configuration is easier to control. In this configuration, P-waves show generally very low signal-to-noise ratios but surface waves propagating along the free surface - here Rayleigh waves - show large amplitudes and are well suited for the investigation of superficial layering. Furthermore, surface wave dispersion is sensitive also to gradual changes of the structure with depth as usually present in real structures. This is another advantage of ultrasonic surface wave studies as body waves are not reflected by gradual internal changes in the structure and methods based on reflected body waves may not be applied in these cases. Here, we show examples for ultrasonic surface measurements that are generally of high quality. Forward mo

Cristiano, Luigia; Erkul, Ercan; Jepsen, Kalle; Meier, Thomas; Vanacore, Stefano; Stefani, Grete

2014-05-01

381

Passivation Of High-Temperature Superconductors  

NASA Technical Reports Server (NTRS)

Surfaces of high-temperature superconductors passivated with native iodides, sulfides, or sulfates formed by chemical treatments after superconductors grown. Passivating compounds nearly insoluble in and unreactive with water and protect underlying superconductors from effects of moisture. Layers of cuprous iodide and of barium sulfate grown. Other candidate passivating surface films: iodides and sulfides of bismuth, strontium, and thallium. Other proposed techniques for formation of passivating layers include deposition and gas-phase reaction.

Vasquez, Richard P.

1991-01-01

382

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

383

The Passive in Technical and Scientific Writing.  

ERIC Educational Resources Information Center

Almost every discussion of technical or scientific writing style mentions the passive voice as a stylistic choice to avoid. However, the passive voice does have legitimate uses in technical and scientific writing--the problem is to define the appropriate or effective uses and the inappropriate or ineffective ones. An examination of passive voice…

Rodman, Lilita

384

Nondestructive characterization of ductile cast iron by magnetic adaptive testing  

NASA Astrophysics Data System (ADS)

This paper reports correlation of magnetic descriptors with Brinell hardness and conductivity of ductile cast iron, aiming to develop a novel nondestructive method by magnetic adaptive testing. Four series of cast iron staircase-shaped samples were investigated by this method, where different cooling rates of samples during casting resulted in different structures of each sample. The flat samples were magnetized by an attached yoke, and sensitive descriptors were obtained from a proper evaluation, based on the measurements of series of magnetic minor hysteresis loops, without magnetic saturation of the samples. Results of the nondestructive magnetic tests were compared with destructive mechanical measurements of Brinell hardness and conductivity and good correlation was found between them.

Vertesy, G.; Uchimoto, T.; Tomáš, I.; Takagi, T.

2010-10-01

385

Ultrasonic wave attenuation measurement for nondestructive evaluation of concrete  

NASA Astrophysics Data System (ADS)

Various nondestructive evaluation methods using the propagating velocity and attenuation of an ultrasonic wave have been studied. The ultrasonic wave attenuation is more sensitive on evaluating to damage assessment in the medium than the ultrasonic wave velocity method. In this paper, the nondestructive evaluation technique using self-compensating frequency response function is proposed to measure the quantitative ultrasonic wave attenuation on cement-based materials. The proposed technique is able to measure inherent attenuation of material, not its relative attenuation. In advance, the reproducibility and relevancy of proposed technique are validated by an experimental comparison of conventional measurement and proposed ultrasonic wave attenuation measurement on cement-based material. In addition, the ultrasonic attenuation measurements are able to characterize the size distribution and volume fraction of entrained air voids in cement-based materials.

Yim, Hong Jae; Kim, Jae Hong; Kwak, Hyo-Gyoung

2010-03-01

386

The use of infrared thermography for nondestructive evaluation of joints  

NASA Astrophysics Data System (ADS)

A junction between two similar, or dissimilar, materials represents generally a weak structural point and so it requires accurate choice of the most adequate joining technique and nondestructive evaluation of joined parts whatever the joining technique. The attention of the present paper is focused on the aid provided by infrared thermography for nondestructive evaluation of three types of joints: aluminum adhesively bonded joints, stainless steel laser welded joints and Glare ® mechanical fastened joints. Both techniques, pulse and modulated thermography with optical stimulation, are used. The attention is particularly focused on the second method because phase images are practically not affected by local nonuniform heating and/or local variation of the emissivity coefficient as thermal images.

Meola, Carosena; Carlomagno, Giovanni M.; Squillace, Antonino; Giorleo, Giuseppe

2004-12-01

387

Using modern nondestructive testing techniques for plant reliability; Part 1  

SciTech Connect

Nondestructive testing techniques are increasingly applied to equipment, systems, and components to ensure the continued safety and performance reliability of operating chemical plants and refineries. The various nondestructive examinations used include not only the conventional methods such as ultrasonic, radiographic, magnetic particle, and liquid penetrant examinations, but also techniques such as eddy current testing, pipe crawlers for internal visual pipe inspections with video cameras, infrared techniques, replication, capacitive strain gage testing, etc. Special procedures may be required for the early detection of leaks applicable to vessels and equipment provided with weep holes or other leak detection systems. Examples of the applications of these various techniques and of the results detected will be presented. In all these examinations, it is important to separate those indications that represent deterioration, which potentially can lead to failures, from other inconsequential indications involving minor corrosion, superficial surface fissuring, or original manufacturing or welding defects.

Thielsch, H.; Cone, F. (Thielsch Engineering, Inc., Cranston, RI (United States))

1994-04-01

388

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.

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

2013-01-01

389

Aging management of major LWR components with nondestructive evaluation  

SciTech Connect

Nondestructive evaluation of material damage can contribute to continued safe, reliable, and economical operation of nuclear power plants through their current and renewed license period. The aging mechanisms active in the major light water reactor components are radiation embrittlement, thermal aging, stress corrosion cracking, flow-accelerated corrosion, and fatigue, which reduce fracture toughness, structural strength, or fatigue resistance of the components and challenge structural integrity of the pressure boundary. This paper reviews four nondestructive evaluation methods with the potential for in situ assessment of damage caused by these mechanisms: stress-strain microprobe for determining mechanical properties of reactor pressure vessel and cast stainless materials, magnetic methods for estimating thermal aging damage in cast stainless steel, positron annihilation measurements for estimating early fatigue damage in reactor coolant system piping, and ultrasonic guided wave technique for detecting cracks and wall thinning in tubes and pipes and corrosion damage to embedded portion of metal containments.

Shah, V.N.; MacDonald, P.E.; Akers, D.W.; Sellers, C. [Idaho National Engineering and Environmental Lab., Idaho Falls, ID (United States); Murty, K.L.; Miraglia, P.Q.; Mathew, M.D. [North Carolina State Univ., Raleigh, NC (United States); Haggag, F.M. [Advanced Technology Corp. (United States)

1997-12-31

390

An assessment of nondestructive testing technologies for chemical weapons monitoring  

SciTech Connect

The US Department of Energy (DOE), with the US Army Chemical Research, Development and Engineering Center (CRDEC) under the sponsorship of the Defense Nuclear Agency (DNA), completed testing of Nondestructive Evaluation (NDE) technology on live agent systems. The tests were conducted at Tooele Army Depot during August 1992. The Nondestructive Evaluation systems were tested for potential use in verifying chemical treaty requirements. Five technologies, two neutron and three acoustic, were developed at DOE laboratories. Two systems from the United Kingdom (one neutron and one acoustic) were also included in the field trials. All systems tested showed the ability to distinguish among the VX, GB, and Mustard. Three of the systems (two acoustic and one neutron) were used by On-Site Inspection Agency (OSIA) personnel.

Taylor, T.T.

1993-05-01

391

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

392

Non-Destructive Techniques Based on Eddy Current Testing  

PubMed Central

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.

Garcia-Martin, Javier; Gomez-Gil, Jaime; Vazquez-Sanchez, Ernesto

2011-01-01

393

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

394

Magnetic field exposure in a nondestructive testing operation.  

PubMed

Nondestructive testing is any technique used to inspect the integrity of a manufactured item without diminishing its future usefulness. Magnetic particle inspection is one type of nondestructive testing that uses electromagnetism in the inspection procedure, thus potentially exposing the operator to magnetic fields. During magnetic particle inspection, investigators took peak magnetic field measurements of 8 turbine engine shafts at a turbine engine overhaul and repair center. They recorded 95 peak magnetic field measurements, ranging from < 0.1 to 29.27 mT. The exposure values measured were among the highest reported in the occupational setting. Further work is needed to characterize magnetic field exposures in magnetic particle inspection operations--in particular, by differentiating magnetic field magnitude by current frequency--and to understand exposure as it relates to different types of magnetic particle inspection devices. PMID:18458022

Lippert, Julia F; Lacey, Steven E; Kennedy, Kathleen J; Esmen, Nurtan A; Buchanich, Jeanine M; Marsh, Gary M

2007-01-01

395

Nondestructive inspection systems for boiler tubes. Final report  

Microsoft Academic Search

It was the objective of this project to demonstrate the feasibility of improved boiler tube inspections through the use of state-of-the-art nondestructive evaluation (NDE) methods. Although the maturity of advanced NDE methods was originally over-estimated, particularly for the power boiler environment, very substantial progress was made in the course of the work. Four NDE techniques were scheduled for feasibility trials.

R. H. Richman; T. W. Rettig; S. R. Paterson

1986-01-01

396

Nondestructive quantitative stress characterization of wire rope and steel cables  

NASA Astrophysics Data System (ADS)

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. A detailed description of the results and the methodologies used to obtain them are provided.

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

1998-03-01

397

Quantitative Nondestructive Evaluation of Automotive Glass Fiber Composites  

Microsoft Academic Search

Thermographic, ultrasonic and acoustic emission nondestructive evalua tion (NDE) characterizations of flawed and unflawed SMC-R25, SMC-R50 and XMC-3 composites are conducted. For various flawed and unflawed states of the composites, these NDE characterizations are correlated with both flaw state and tensile fracture strength. Drilled-holes and V-notch flaws of various sizes result in correspondingly lower tensile strengths; however, in creases in

James H. Williams; Samson S. Lee; Tony K. Wang

1982-01-01

398

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

399

NASA CR-2120 - Summary of nondestructive testing theory and practice  

NASA Technical Reports Server (NTRS)

This is a familiarization report of nondestructive testing (ndt) prepared by staff of the Battelle Columbus Laboratories on a NASA contract. There is a short introduction, a chapter on applicability of ndt which is illustrated with examples of typical defects and includes tables comparing the characteristics, interrelationships, and costs of the different techniques. There are chapters dealing with penetrants, magnetic particle radiography, ultrasonics, and eddy currents. New techniques are described.

Meister, R. P.

1974-01-01

400

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

401

Non-destructive sub-THz CW imaging  

Microsoft Academic Search

A simple, compact CW sub-THz imaging system, utilizing a 0.2 and 0.6 THz Gunn diode source is presented. A silicon beam lead diode detector and a Golay cell are used for the detection. Various results are presented, which show that the CW THz imaging modality is suitable for diverse applications, such as non-destructive testing and security. The key components of

Nicholas Karpowicz; Hua Zhong; Jingzhou Xu; Kuang-I. Lin; Jenn-Shyong Hwang; Xi-Cheng Zhang

2005-01-01

402

Non-Destructive Evaluation (NDE) Applications of THz Radiation  

Microsoft Academic Search

The technology and applications of time domain terahertz (THz) imaging to non-destructive evaluation (NDE) will be discussed. THz imaging has shown great promise in 2 and 3 dimensional non-contact inspection of non-conductive materials such as plastics, foam, composites, ceramics, paper, wood and glass. THz imaging employs safe low power non-ionizing electromagnetic pulses, with lateral resolution < 200 um, and depth

David Zimdars

2005-01-01

403

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

404

Optical and mechanical nondestructive tests for measuring tomato fruit firmness  

NASA Astrophysics Data System (ADS)

Ripening is one of the most important processes to occur in fruits which involve changes in color, flavor, and texture. An important goal in quality control of fruits is to substitute traditional sensory testing methods with reliable nondestructive tests (NDT). In this work we study the firmness of tomato fruits by using optical and mechanical NDT. Optical and mechanical parameters, measured along the tomato shelf life, are shown.

Manivel-Chávez, Ricardo A.; Garnica-Romo, M. G.; Arroyo-Correa, Gabriel; Aranda-Sánchez, Jorge I.

2011-08-01

405

Development of nondestructive evaluation methods for structural ceramics  

Microsoft Academic Search

During the past year, the focus of our work on nondestructive evaluation (NDE) methods was on the development and application of these methods to technologies such as ceramic matrix composite (CMC) hot-gas filters, CMC high-temperature heat exchangers, and CMC ceramic\\/ceramic joining. Such technologies are critical to the ''Vision 21 Energy-Plex Fleet'' of modular, high-efficiency, low-emission power systems. Specifically, our NDE

Ellingson

1998-01-01

406

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

407

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

408

Nondestructive characterization of fiber couplers: the technique and its applications  

Microsoft Academic Search

A non-destructive technique for characterising couplers by means of a local perturbation is described. A CO2 laser beam is scanned along the coupler length inducing a local perturbation to the coupler eigenmodes. Asymmetric and symmetric perturbations give respectively, accurate mapping of power-evolution and coupler-waist shape. Using this technique, both the information of the power distribution and coupling profile along the

Carlos Alegria; Michalis N. Zervas

2003-01-01

409

Study of electromagnetic acoustic emission for non-destructive testing  

Microsoft Academic Search

In this paper, the finite element analysis of a recently developed electromagnetic acoustic emission (EMAE) which can be used for damage assessment of thin walled conducting structures has been reported. Due to the local high-intensity stress field generated by the electro-magnetically induced high-density current pulse, EMAE can locate small flaws or cracks in thin-walled structures non-destructively to allow inspection of

Liang Jin; Suzhen Liu; Qingxin Yang; Haiyan Chen; Chuang Zhang

2008-01-01

410

Nondestructive test to track pollutant transport into landfill liners  

Microsoft Academic Search

Over the last decade, waste disposal has become a particularly sensitive issue in Algeria. New legislation concerning landfill\\u000a liner design has been adopted. Traditional methods of landfill liner characterization involve soil sampling and chemical analysis,\\u000a which are costly, destructive and time-consuming. New techniques are currently being investigated that aim to provide nondestructive\\u000a liner characterisation. This paper details technical aspects associated

A. Bezzar; F. Ghomari

2009-01-01

411

Nondestructive characterization of RBSOA of high-power bipolar transistors  

NASA Astrophysics Data System (ADS)

Reverse-bias safe operating area (RBSOA) of high-power Darlington transistors is characterized using a 120 A/1000 V nondestructive reverse-bias second breakdown tester designed and fabricated at Virginia Polytechnic Institute and State University. Elaborate RBSOA characteristics are generated with different forward/reverse base drives and collector current levels. The effects of elevated case temperature and second-base drive on RBSOA of four-terminal Darlington devices are also discussed.

Jovanovic, M. M.; Lee, F. C.; Chen, D. Y.

1986-03-01

412

Human Health Effects Assays.  

National Technical Information Service (NTIS)

The use of assays to evaluate and assist in predicting potentially adverse human health effects associated with exposure to pollutants in water (that is, municipal wastewater, sewage sludge, ambient water, and drinking water) is the focus of the review.

L. Fradkin C. Sonich-Mullin M. Cerny C. Kruger F. Cavender

1989-01-01

413

Factor V assay  

MedlinePLUS

The factor V assay is a blood test to measure the activity of factor V. This is a substances involved in blood clotting ( ... Decreased factor V activity may be related to: Deficiency of factor ... at birth (congenital) Disseminated intravascular coagulation ( ...

414

Interior design for passive solar homes  

SciTech Connect

The increasing emphasis on refinement of passive solar systems has brought recognition to interior design as an integral part of passive solar architecture. Interior design can be used as a finetuning tool minimizing many of the problems associated with passive solar energy use in residential buildings. In addition, treatment of interior space in solar model homes may be a prime factor in determining sales success. A new style of interior design is evolving in response to changes in building form incorporating passive solar design features. The psychology behind passive solar architecture is reflected in interiors, and selection of interior components increasingly depends on the functional suitability of various interior elements.

Breen, J. C.

1981-07-01

415

Interior design for passive solar homes  

NASA Astrophysics Data System (ADS)

The increasing emphasis on refinement of passive solar systems brought recognition to interior design as an integral part of passive solar architecture. Interior design can be used as a finetuning tool minimizing many of the problems associated with passive solar energy use in residential buildings. In addition, treatment of interior space in solar model homes may be a prime factor in determining sales success. A new style of interior design is evolving in response to changes in building from incorporating passive solar design features. The psychology behind passive solar architecture is reflected in interiors, and selection of interior components increasingly depends on the functional suitably of various interior elements.

Breen, J. C.

1981-07-01

416

New Rapid Spore Assay  

NASA Astrophysics Data System (ADS)

The presentation will detail approved Planetary Protection specifications for the Rapid Spore Assay for spacecraft components and subsystems. Outlined will be the research and studies on which the specifications were based. The research, funded by ESA and NASA/JPL, was conducted over a period of two years and was followed by limited cleanroom studies to assess the feasibility of this assay during spacecraft assembly.

Kminek, Gerhard; Conley, Catharine

2012-07-01

417

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

418

PASSIVE TRANSFER OF TRANSPLANTATION IMMUNITY  

PubMed Central

Passive transfer of tritiated thymidine labeled lymphoid cells sensitized to homologous tissues into non-sensitized isologous hosts resulted in accelerated rejection of homologous skin grafts in the recipients. Despite 33 per cent label of the suspension, only rare labeled sensitized lymphoid cells could be found at the site of rejection. Passive transfer of sensitized lymphoid cells in millipore chambers implanted subcutaneously or intraperitoneally in non-sensitized isologous hosts resulted in accelerated homograft rejection in the recipients. Transfer of transplantation immunity could not be accomplished with serum from sensitized hosts. The rejection of homologous tissues without the physical presence of the sensitized cell at the graft site suggested that a humoral agent produced by the cell was capable of rejecting the homograft.

Najarian, John S.; Feldman, Joseph D.

1962-01-01

419

Passive Photonic Devices in Glass  

NASA Astrophysics Data System (ADS)

Femtosecond laser microfabrication offers the potential for writing passive photonic circuits inside bulk glasses, for use in last-mile photonic networks, sensing, and lab-on-a-chip applications. In this chapter, the fabrication methods for writing low-loss optical waveguides along with waveguide and device characterization techniques are reviewed. The advantages and disadvantages of femtosecond laser writing are analyzed and compared with existing planar lithographic fabrication techniques.

Eaton, Shane M.; Herman, Peter R.

420

Interferoceiver, ISAR, and passive identification  

NASA Astrophysics Data System (ADS)

Optical fiber recirculation loops will change the technical foundation of radar and electronic warfare technologies. It becomes possible to measure Doppler beating with a single pulse, to map out micro Doppler signature with a resolution better than 1.0 Hz, and to take sharp IASR images of targets which are more than several hundred miles away. With fine micro Doppler signature and high precision ISAR images, the passive identification of targets will become a reality.

Li, Ming-Chiang

2006-06-01

421

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

422

The effects of maternal passive smoking on maternal milk lipid.  

PubMed

Passive smoking was long overlooked by those in the medical and legal professions as being harmful to one's health, but in recent years the negative effect of passive smoking has come to the fore in the media and laws have been changed so that less people are obliged to unwillingly suffer from passive smoking, particularly in the workplace and in indoor settings. To study the effects of environmental tobacco smoking exposure during the breast-feeding period on maternal milk lipids. This cohort study was conducted on 45 mothers environmental tobacco smoking exposure and 40 non-exposed post-partum mothers referred to the Shahid Ayat health center, Tehran, Iran. Socioeconomic conditions and the demographic characteristics of exposed and non-exposed groups were recorded. Milk samples were collected twice- at baseline (5-7 days after delivery) and four months after delivery. The samples were reserved at -20°C until assay. Milk lipids including cholesterol, triglyceride (TG), high density lipoprotein (HDL) and low density lipoprotein (LDL) were evaluated. Dietary intake assessment was performed by means of the 24-hour dietary recall questionnaire both times. Maternal occupation status and education levels were significantly different between the two groups. Lipids profiles of milk were significantly higher 5-7 days after delivery in the non-exposed group and four months after delivery.  Dietary intake was not significantly different between the two groups. Maternal environmental tobacco smoking exposure affects milk lipids which are essential for infant growth. PMID:24901858

Baheiraei, Azam; Shamsi, Azar; Khaghani, Shahnaz; Shams, Sedigheh; Chamari, Maryam; Boushehri, Hoda; Khedri, Azam

2014-04-01

423

Gamma neutron assay method and apparatus  

DOEpatents

The gamma neutron assay technique is an alternative method to standard safeguards techniques for the identification and assaying of special nuclear materials in a field or laboratory environment, as a tool for dismantlement and destruction of nuclear weapons, and to determine the isotopic ratios for a blend-down program on uranium. It is capable of determining the isotopic ratios of fissionable material from the spontaneous or induced fission of a sample to within approximately 0.5%. This is based upon the prompt coincidence relationships that occur in the fission process and the proton conservation and quasi-conservation of nuclear mass (A) that exists between the two fission fragments. The system is used in both passive (without an external neutron source and active (with an external neutron source) mode. The apparatus consists of an array of neutron and gamma-ray detectors electronically connected to determine coincident events. The method can also be used to assay radioactive waste which contains fissile material, even in the presence of a high background radiation field.

Cole, Jerald D. (Idaho Falls, ID); Aryaeinejad, Rahmat (Idaho Falls, ID); Greenwood, Reginald C. (Idaho Falls, ID)

1995-01-01

424

Gamma neutron assay method and apparatus  

DOEpatents

The gamma neutron assay technique is an alternative method to standard safeguards techniques for the identification and assaying of special nuclear materials in a field or laboratory environment, as a tool for dismantlement and destruction of nuclear weapons, and to determine the isotopic ratios for a blend-down program on uranium. It is capable of determining the isotopic ratios of fissionable material from the spontaneous or induced fission of a sample to within approximately 0.5%. This is based upon the prompt coincidence relationships that occur in the fission process and the proton conservation and quasi-conservation of nuclear mass (A) that exists between the two fission fragments. The system is used in both passive (without an external neutron source) and active (with an external neutron source) mode. The apparatus consists of an array of neutron and gamma-ray detectors electronically connected to determine coincident events. The method can also be used to assay radioactive waste which contains fissile material, even in the presence of a high background radiation field. 7 figures.

Cole, J.D.; Aryaeinejad, R.; Greenwood, R.C.

1995-01-03

425

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.

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

2012-01-01

426

Tested method to minimize plutonium assay discrepancies between laboratories  

SciTech Connect

Plutonium assay differences are frequently observed between laboratories exchanging plutonium dioxide powders. These differences are commonly the result of chemical changes and/or nonhomogeneities in sampled materials. The irregularities are often caused by moisture absorption during sampling, packaging, shipment, and storage of the materials. A method is proposed which eliminates the effects of chemical change in samples, particularly moisture absorption, and minimizes sampling error. A nondestructive thermal watts/gram test on every preweighed sampled and total dissolution of these samples for chemical assay are the primary features which make this method effective. Because this method minimizes the error related to exchange material, it is possible to design an interlaboratory exchange program which demonstrates the assay capabiliies of the participants. In an experiment performed to demonstrate the effectiveness of this method, three PuO/sub 2/ batches of varying isotopic composition were synthesized at Mound to be used in the exchange tess. Powder sample aliquots from each batch were weighed directly into their vials under controlled atmospheric conditions. Calorimetric heat measurements were made on each vial to test homogeneity and verify sample weight. Six vials of each batch were chemically assayed at Mound and six at NBL (New Brunswick Laboratory). Both laboratories chose controlled-potential coulometry as the chemical assay technique because of its demonstrated precision and accuracy. Total dissolution of preweighed exchange samples eliminated the need for laborious and usually futile heating to return the material to its original condition. The mean chemical assay values obtained by Mound and NBL agree to within 0.01% for each of the compositions tested. Testing of both chemical assay and calorimetric data revealed no sampling error throughout the experiment.

Seiler, R.J.; Goss, R.L.; Rodenburg, W.W.; Rogers, D.R.

1982-01-29

427

Chromogenic factor VIII activity assay.  

PubMed

Factor VIII (FVIII) may be measured by three different methodologies in the clinical laboratory: one-stage clotting assay, two-stage clotting assay, and chromogenic assay. These assays differ in ease of use, variety of reagents available, sensitivity to mild hemophilia A, and interference from lupus anticoagulants. This review will outline the methodology for each of the FVIII activity assays, with a discussion of assay interferences and variability. In some cases, chromogenic FVIII activity assays may be preferable to clot-based assays, and these clinical situations will be reviewed as well. Am. J. Hematol. 89:781-784, 2014. © 2014 Wiley Periodicals, Inc. PMID:24676945

Moser, Karen A; Adcock Funk, Dorothy M

2014-07-01

428

Assays for calcitonin receptors  

SciTech Connect

The assays for calcitonin receptors described focus on their use in the study of the well-established target organs for calcitonin, bone and kidney. The radioligand used in virtually all calcitonin binding studies is /sup 125/I-labelled salmon calcitonin. The lack of methionine residues in this peptide permits the use of chloramine-T for the iodination reaction. Binding assays are described for intact bone, skeletal plasma membranes, renal plasma membranes, and primary kidney cell cultures of rats. Studies on calcitonin metabolism in laboratory animals and regulation of calcitonin receptors are reviewed.

Teitelbaum, A.P.; Nissenson, R.A.; Arnaud, C.D.

1985-01-01

429

Automated phantom assay system  

SciTech Connect

This paper describes an automated phantom assay system developed for assaying phantoms spiked with minute quantities of radionuclides. The system includes a computer-controlled linear-translation table that positions the phantom at exact distances from a spectrometer. A multichannel analyzer (MCA) interfaces with a computer to collect gamma spectral data. Signals transmitted between the controller and MCA synchronize data collection and phantom positioning. Measured data are then stored on disk for subsequent analysis. The automated system allows continuous unattended operation and ensures reproducible results.

Sisk, D.R.; Nichols, L.L.; Olsen, P.C.

1991-11-01

430

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

2011-03-08

431

The passive-aggressive organization.  

PubMed

Passive-aggressive organizations are friendly places to work: People are congenial, conflict is rare, and consensus is easy to reach. But, at the end of the day, even the best proposals fail to gain traction, and a company can go nowhere so imperturbably that it's easy to pretend everything is fine. Such companies are not necessarily saddled with mulishly passive-aggressive employees. Rather, they are filled with mostly well-intentioned people who are the victirms of flawed processes and policies. Commonly, a growing company's halfhearted or poorly thought-out attempts to decentralize give rise to multiple layers of managers, whose authority for making decisions becomes increasingly unclear. Some managers, as a result, hang back, while others won't own up to the calls they've made, inviting colleagues to second-guess or overturn the decisions. In such organizations, information does not circulate freely, and that makes it difficult for workers to understand the impact of their actions on company performance and for managers to correctly appraise employees' value to the organization. A failure to accurately match incentives to performance stifles initiative, and people do just enough to get by. Breaking free from this pattern is hard; a long history of seeing corporate initiatives ignored and then fade away tends to make people cynical. Often it's best to bring in an outsider to signal that this time things will be different. He or she will need to address every obstacle all at once: clarify decision rights; see to it that decisions stick; and reward people for sharing information and adding value, not for successfully negotiating corporate politics. If those steps are not taken, it's only a matter of time before the diseased elements of a passive-aggressive organization overwhelm the remaining healthy ones and drive the company into financial distress. PMID:16250627

Kaplan, Robert S; Norton, David P

2005-10-01

432

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.

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

433

Physics of passive solar buildings  

SciTech Connect

Primary emphasis in the paper is on methods of characterizing and analyzing passive solar buildings. Simplifying assumptions are described which make this analysis tractable without compromising significant accuracy or loss of insight into the basic physics of the situation. The overall nature of the mathematical simulation approach is described. Validation procedures based on data from test rooms and monitored buildings are outlined. Issues of thermal comfort are discussed. Simplified methods of analysis based on correlation procedures are reported and the nature of the economic conservation-solar optimization process is explored. Future trends are predicted.

Balcomb, J.D.

1981-01-01

434

PASSIVE TRANSFER OF TRANSPLANTATION IMMUNITY  

PubMed Central

Passive transfer of homograft immunity was successfully achieved by injection of the supernatant obtained from tissue-sensitized lymphoid cells disrupted by sonic vibration. The effective substance destroyed specific skin homografts within 6 days but did not reject non-specific skin grafts in this time. No evidence of transferred antigen or of transfer factor was found when the effective material was passed to irradiated recipients carrying test grafts. By a variety of physiochemical procedures the "soluble substance" behaved like a gamma globulin and was considered to be a transplantation antibody.

Najarian, J. S.; Feldman, J. D.

1963-01-01

435

Passive solar reflector satellite revisited  

NASA Technical Reports Server (NTRS)

Passive light weight reflectors in space which direct the incident solar energy to a specified location on the Earth surface are proposed as an alternative system for the solar power satellite to overcome conversion losses and to avoid the need for photovoltaic cells. On Earth, either photovoltaic cells or a steam turbine alternator on a solar tower, or a similar conventional, relatively high efficiency cycle are used for electricity generation. The constraints which apply to the design of the optical system if a single satellite is placed in geostationary orbit are outlined. A single lens and a two lens system are discussed.

Polk, C.; Daly, J. C.

1980-01-01

436

Passive Testing of Web Services  

NASA Astrophysics Data System (ADS)

This paper presents a methodology to perform passive testing based on invariants of distributed systems with time information. This approach is supported by the following idea: A set of invariants represents the most relevant expected properties of the implementation under test. Intuitively, an invariant expresses the fact that each time the system under test performs a given sequence of actions, then it must exhibit a behavior reflected in the invariant. We call these invariants local because they only check the correctness of the logs that have been recorded in each isolated system.

Andrés, César; Cambronero, M. Emilia; Núñez, Manuel

437

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.

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

2013-01-01

438

Nondestructive defect characterization of SiC substrates and epilayers  

NASA Astrophysics Data System (ADS)

This study presents a nondestructive and in-depth defect characterization method, based on the principle of polarized light microscopy (PLM), which can be used to quickly evaluate SiC substrates and epilayers. The developed PLM system has the capability to map, on a wafer scale, micropipes, elementary screw dislocations, and domain boundaries in SiC wafers. One unique feature of the PLM system is the ability to characterize the wafer with and without an epilayer, providing a newly found opportunity to investigate threading defect propagation in the overgrown epilayer. The correlation between SiC substrate defects and epilayer defects will be established.

Ma, Xianyun; Sudarshan, Tangali

2004-05-01

439

Nondestructive Probing Scheme of Quantum State Without Quantum Correlation  

NASA Astrophysics Data System (ADS)

We study a scheme that an auxiliary qubit is introduced for probing the information of the given bipartite quantum state, while the correlations of the probed quantum state and even the probed state itself are not disturbed after the probing, which means nondestructive probing. We find that, in order to guarantee the invariance of the correlations of the probed state, neither quantum entanglement nor quantum discord between the auxiliary qubit and the probed states can be present. This could make us reconsider the role of quantum correlation in some quantum information processing tasks.

Li, Zhenni; Yu, Chang-shui; Ding, Shuxue; Tang, Zunyi

2013-10-01

440

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

441

Potential techniques for non-destructive evaluation of cable materials  

SciTech Connect

This paper describes the connection between mechanical degradation of common cable materials in radiation and elevated temperature environments and density increases caused by the oxidation which leads to this degradation. Two techniques based on density changes are suggested as potential non-destructive evaluation (NDE) procedures which may be applicable to monitoring the mechanical condition of cable materials in power plant environments. The first technique is direct measurement of density changes, via a density gradient column, using small shavings removed from the surface of cable jackets at selected locations. The second technique is computed X-ray tomography, utilizing a portable scanning device.

MGillen, K.T.; Clough, R.L. [Sandia National Labs., Albuquerque, NM (United States); Mattson, B.; Stenberg, B. [Royal Inst. of Tech., Stockholm (Sweden). Dept. of Polymer Technology; Oestman, E. [Skega AB, Ersmark (Sweden)

1993-03-01

442

Potential techniques for non-destructive evaluation of cable materials  

SciTech Connect

This paper describes the connection between mechanical degradation of common cable materials in radiation and elevated temperature environments and density increases caused by the oxidation which leads to this degradation. Two techniques based on density changes are suggested as potential non-destructive evaluation (NDE) procedures which may be applicable to monitoring the mechanical condition of cable materials in power plant environments. The first technique is direct measurement of density changes, via a density gradient column, using small shavings removed from the surface of cable jackets at selected locations. The second technique is computed X-ray tomography, utilizing a portable scanning device.

MGillen, K.T.; Clough, R.L. (Sandia National Labs., Albuquerque, NM (United States)); Mattson, B.; Stenberg, B. (Royal Inst. of Tech., Stockholm (Sweden). Dept. of Polymer Technology); Oestman, E. (Skega AB, Ersmark (Sweden))

1993-01-01

443

Nondestructive characterization of corrosion protective coatings on aluminum alloy substrates  

SciTech Connect

This paper describes the initial phase of the development of a nondestructive, multisensor approach for detecting, quantifying and monitoring degradation of organic coatings applied to aluminum surfaces. Descriptions of the purposes and chemical compositions of layered coatings used on aircraft structures are provided. The discussion then concentrates on ultrasonic thickness measurements. One is the well-established pulse/echo scanning acoustic microscopy and, as a proposed alternative, continuous acoustic waves measurements with a probe in contract to the sample. Advantages and disadvantages of the two methods and their potential as in field applications are discussed.

Hoffmann, J.; Sathish, S.; Khobaib, M.; Meyendorf, N.; Netzelmann, U.; Matikas, T.E.

2000-07-01

444

Nondestructive evaluation of Ni-Ti shape memory alloy  

SciTech Connect

The nondestructive evaluation of nickel titanium (Ni-Ti) alloys for applications such as heat treatment for biomaterials applications (dental) and welding was investigated. Ni-Ti alloys and its ternary alloys are valued for mechanical properties in addition to the shape memory effect. Two analytical approaches were perused in this work. Assessment of the microstructure of the alloy that determines the martensitic start temperature (Ms) of Ni-Ti alloy as a function of heat treatment, and secondly, an attempt to evaluate a Friction Stir Welding, which involves thermo-mechanical processing of the alloy.

Meir, S.; Gordon, S.; Karsh, M.; Ayers, R.; Olson, D. L. [Department of Metallurgical and Materials Engineering, Colorado School of Mines, Golden, CO (United States); Wiezman, A. [Netania (Israel)

2011-06-23

445

Nondestructive and contactless determination of layer and coating thickness  

NASA Astrophysics Data System (ADS)

The paper describes some new developments in the field of contactless and nondestructive determination of the layer and coating thickness on different substrates. 1) The first method is based on millimeterwaves which are emitted and re-ceived by a compact integrated radar sensor. 2) Another approach is based on thermal effects induced in the coating by flash heating or laser light heating. The temperature response of the test object is monitored by an infrared sensor. 3) With the help of an airborne ultrasonic transducer the thickness of powder coating, e.g. ceramics-coating on steel, can be determined contactlessly with an accuracy of better than 5 ?m.

Sklarczyk, C.; Netzelmann, U.; Kreier, P.; Gebhardt, W.

2005-05-01

446

Non-Destructive Evaluation for Civil Engineering Structures and Materials  

NASA Astrophysics Data System (ADS)

This paper describes the challenges associated with the application of non-destructive evaluation techniques to the civil engineering infrastructure. Significant inspection tasks and structural defect types are first defined. Theoretical bases and experimental requirements of several current NDE techniques are then described, where case studies of application of the described techniques to specific structures are highlighted. Limitations of the current technology in achieving the inspection goals are identified. Finally, discussion about future directions of civil structure NDE, in terms of newly developed and promising NDE techniques, is presented.

Popovics, John S.

2004-02-01

447

Nondestructive inspection and evaluation of composite-material flywheels  

SciTech Connect

Several composite panels and flywheel designs were evaluated in support of the Mechanical Energy Storage Technology (MEST) project. Conventional nondestructive evaluation (NDE) technology was used on the panels and flywheels. All flywheels and panels were radiographed and, where practical, were also inspected using ultrasonic techniques. The results provided information about the structural features of flywheels and materials. This information is useful for the quality control of fabrication procedures. The detection of apparent flaws in fabrication cannot be related to the ultimate strength until failure mechanisms in composite materials have been fully defined. Therefore, the location of detected flaws should be recorded for later comparison with dynamic and destructive evaluations.

Boyd, D M; Maxfield, B W; Kulkarni, S V; Schwarber, A J

1982-02-24

448

Nondestructive interferometric characterization of an optical dipole trap  

SciTech Connect

A method for nondestructive characterization of a dipole-trapped atomic sample is presented. It relies on a measurement of the phase shift imposed by cold atoms on an optical pulse that propagates through a free-space Mach-Zehnder interferometer. Using this technique we are able to determine, with very good accuracy, relevant trap parameters such as the atomic sample temperature, trap oscillation frequencies, and loss rates. Another important feature is that our method is faster than conventional absorption or fluorescence techniques, allowing the combination of high-dynamical range measurements and a reduced number of spontaneous emission events per atom.

Petrov, Plamen G.; Oblak, Daniel; Alzar, Carlos L. Garrido; Kjaergaard, Niels; Polzik, Eugene S. [QUANTOP, Danish National Research Foundation Centre of Quantum Optics, Niels Bohr Institute, DK-2100 Copenhagen O (Denmark)

2007-03-15

449

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

450

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

451

Simulation of Ultrasonic and Electromagnetic Nondestructive Evaluation of Corrosion  

NASA Astrophysics Data System (ADS)

The influence of corrosion on ultrasonic and electromagnetic nondestructive evaluation results has been simulated for 2-layer aluminum aircraft fuselage. Simulations have been performed with respect to ultrasonic time-of-flight measurements aiming on the detection of corrosion at the backwall of the first aluminum layer. Calculations of the eddy current probe response have been performed, where the thickness of the first and second layer and also the probe-to-specimen lift-off at several eddy current operating frequencies have been varied.

Spies, M.; Yashan, A.; Kropas-Hughes, C. V.

2003-03-01

452

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

453

Coded waveforms for optimised air-coupled ultrasonic nondestructive evaluation.  

PubMed

This paper investigates various types of coded waveforms that could be used for air-coupled ultrasound, using a pulse compression approach to signal processing. These are needed because of the low signal-to-noise ratios that are found in many air-coupled ultrasonic nondestructive evaluation measurements, due to the large acoustic mismatch between air and many solid materials. The various waveforms, including both swept-frequency signals and those with binary modulation, are described, and their performance in the presence of noise is compared. It is shown that the optimum choice of modulation signal depends on the bandwidth available and the type of measurement being made. PMID:24726137

Hutchins, David; Burrascano, Pietro; Davis, Lee; Laureti, Stefano; Ricci, Marco

2014-09-01

454

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

455

Nondestructive identification of isotopes using nuclear resonance fluorescence.  

PubMed

Nondestructive identification of heavy isotopes concealed in a thick iron box has been demonstrated by using nuclear resonance fluorescence. A quasi-monochromatic photon beam produced by the collision of laser quanta with high energy electrons was used for resonant excitation of nuclear levels in (206)Pb and (208)Pb. By measuring the resonant ? rays emitted from (206)Pb and (208)Pb, each of these isotopes were clearly identified. The ratio of the effective thickness, i.e., concentration distribution, of these isotopes was deduced from the relative intensities of the measured nuclear resonance fluorescence strengths. PMID:22299982

Shizuma, Toshiyuki; Hayakawa, Takehito; Hajima, Ryoichi; Kikuzawa, Nobuhiro; Ohgaki, Hideaki; Toyokawa, Hiroyuki

2012-01-01

456

Nondestructive identification of isotopes using nuclear resonance fluorescence  

SciTech Connect

Nondestructive identification of heavy isotopes concealed in a thick iron box has been demonstrated by using nuclear resonance fluorescence. A quasi-monochromatic photon beam produced by the collision of laser quanta with high energy electrons was used for resonant excitation of nuclear levels in {sup 206}Pb and {sup 208}Pb. By measuring the resonant {gamma} rays emitted from {sup 206}Pb and {sup 208}Pb, each of these isotopes were clearly identified. The ratio of the effective thickness, i.e., concentration distribution, of these isotopes was deduced from the relative intensities of the measured nuclear resonance fluorescence strengths.

Shizuma, Toshiyuki; Hayakawa, Takehito; Hajima, Ryoichi [Quantum Beam Science Directorate, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195 (Japan); Kikuzawa, Nobuhiro [J-PARC Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195 (Japan); Ohgaki, Hideaki [Institute of Advanced Energy, Kyoto University, Uji, Kyoto 611-0011 (Japan); Toyokawa, Hiroyuki [National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki 305-8568 (Japan)

2012-01-15

457

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

458

Nondestructive evaluation of FRP composite bridge components using infrared thermography  

NASA Astrophysics Data System (ADS)

This paper presents the findings of an experimental study on the use of Infrared Thermography for nondestructive evaluation of subsurface delaminations in Fiber Reinforced Polymer (FRP) composite bridge decks and concrete columns wrapped with FRP jackets. Composite bridge deck specimens were constructed in the laboratory with varying delamination sizes. The infrared images from the delaminated specimens were compared with undamaged specimens to study the effect of subsurface delaminations on the infrared images. In addition, field tests were conducted using infrared thermography on composite structural members of three bridges located in West Virginia. .

Halabe, U. B.; Alqennah, H.; Gangarao, H. V. S.; Klinkhachorn, P.; Sazonov, E. S.

2002-05-01

459

Gap between active and passive solar heating  

SciTech Connect

The gap between active and passive solar could hardly be wider. The reasons for this are discussed and advantages to narrowing the gap are analyzed. Ten years of experience in both active and passive systems are reviewed, including costs, frequent problems, performance prediction, performance modeling, monitoring, and cooling concerns. Trends are analyzed, both for solar space heating and for service water heating. A tendency for the active and passive technologies to be converging is observed. Several recommendations for narrowing the gap are presented.

Balcomb, J.D.

1985-01-01

460

Passive cigarette smoking increases isoprostane formation  

Microsoft Academic Search

Passive smoking has been demonstrated to exert a variety of deleterious effects eventually resulting in vascular damage. Isoprostanes, a reliable marker of in vivo oxidation injury, have been shown to increase in active cigarette smoking. Data for passive smoking are lacking. We were examining the isoprostane 8-epi-PGF2? in 12 smokers and non-smokers exposed daily to passive cigarette smoke for 12

Hossein Ahmadzadehfar; Anthony Oguogho; Yannis Efthimiou; Harald Kritz; Helmut Sinzinger

2006-01-01

461

Hydrogen passivation of multicrystalline silicon solar cells  

Microsoft Academic Search

The use of hydrogen for passivation of multicrystalline silicon in solar cell technology is described. Three kinds of hydrogen incorporation into mc-Si solar cells have been evaluated: hydrogen diffusion out of a SiN-layer (SiN:H), low-energy hydrogen ion implantation (HII), and remote plasma hydrogen passivation (RPHP). Best results were obtained by RPHP, whereas using HII, damage exceeded the passivation effect to

Ralf Lüdemann

1999-01-01

462

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