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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

Tomographic applications of wavelets in passive nondestructive assay of radioactive waste  

NASA Astrophysics Data System (ADS)

An economically reliable and technologically feasible methodology for assaying radioactive waste is essential for properly disposing of newly generated and legacy radioactive waste. The present research has investigated, developed, and integrated tomographic applications of wavelets into the present segmented gamma scanning (SGS) measurement methodology used for passive nondestructive assay of radioactive waste. The SGS measurement methodology was specifically developed to nondestructively measure the radionuclide content within only low-density, homogeneously drum-packaged scrap and waste using the techniques of gamma-ray spectrometry. A result of this research has been the Tomographic Segmented Gamma Scanner (TSGS) system. This TSGS system supplements a rotation-averaged SGS measurement system with tomographic gamma scanning (TGS) capability that can specifically take into account the effects of larger density and radionuclide distribution non-uniformities when present. This TSGS system allows the throughput to remain high with a less detailed but faster rotation-averaged segment measurement of homogenous radioactive waste, while the TGS capability provides a more detailed but slower spatial radionuclide measurement for assaying heterogeneous radionuclide waste as necessary. Within the experimental part of this research, (1) the tomographic experimental feasibility was established, (2) a TSGS system integrated calibration was designed, (3) collimation sampling problems were studied, (4) SGS and TGS modality-specific comparisons were shown, and finally, (5) the TSGS system precision was measured. An investigation of the applications of wavelets in computerized tomography has lead to the development of a radionuclide computerized tomography (RCT) algorithm able to accurately calculate the measured radionuclide content within heterogeneously packaged scrap and waste. Within the computational part of this research, (1) the optimization of a relaxation parameter that determines the iterative convergence rate within the RCT algorithm was investigated, (2) an efficient wavelet-interpolation method for refining the tomographic reconstruction resolution to allow accurate forward and back-projecting interpolation using simple nearest-neighbor grid-point assignment was developed, (3) the multiresolution analysis of tomographic image reconstructions with applications in wavelet filtering was studied, (4) an exploration of how Daubechies wavelets influence tomographic reconstructions was investigated, and finally, (5) simulated tomographic profile projection data using the Monte Carlo N-Particle Transport Code System (MCNP) was successfully bench marked against experimental data.

Weems, Lance David

1998-07-01

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

Quantifying the passive gamma signal from spent nuclear fuel in support of determining the plutonium content in spent nuclear fuel with nondestructive assay  

SciTech Connect

The objective of safeguarding nuclear material is to deter diversions of significant quantities of nuclear materials by timely monitoring and detection. There are a variety of motivations for quantifying plutonium in spent fuel (SF), by means of nondestructive assay (NDA), in order to meet this goal. These motivations include the following: strengthening the capabilities of the International Atomic Energy Agencies ability to safeguard nuclear facilities, shipper/receiver difference, input accountability at reprocessing facilities and burnup credit at repositories. Many NDA techniques exist for measuring signatures from SF; however, no single NDA technique can, in isolation, quantify elemental plutonium in SF. A study has been undertaken to determine the best integrated combination of 13 NDA techniques for characterizing Pu mass in spent fuel. This paper focuses on the development of a passive gamma measurement system in support the spent fuel assay system. Gamma ray detection for fresh nuclear fuel focuses on gamma ray emissions that directly coincide with the actinides of interest to the assay. For example, the 186-keV gamma ray is generally used for {sup 235}U assay and the 384-keV complex is generally used for assaying plutonium. In spent nuclear fuel, these signatures cannot be detected as the Compton continuum created from the fission products dominates the signal in this energy range. For SF, the measured gamma signatures from key fission products ({sup 134}Cs, {sup 137}Cs, {sup 154}Eu) are used to ascertain burnup, cooling time, and fissile content information. In this paper the Monte Carlo modeling set-up for a passive gamma spent fuel assay system will be described. The set-up of the system includes a germanium detector and an ion chamber and will be used to gain passive gamma information that will be integrated into a system for determining Pu in SF. The passive gamma signal will be determined from a library of {approx} 100 assemblies that have been created to examine the capability of all 13 NDA techniques. Presented in this paper is a description of the passive gamma monitoring instrument, explanation of the work completed thus far involving the source set up methodology and the design optimization process, details of key fission product ratios of interest, limitations and key strengths of the measurement technique, and considerations for integrating this technique with other NDA techniques in order to develop a complete spent fuel assay strategy.

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

2009-01-01

6

Operational Experience with an Imaging Passive/Active Neutron System (IPAN{sup TM}) in a Mature Production Application to Perform WIPP Certified Non-destructive Assays  

SciTech Connect

BIL Solutions Inc. have deployed and operated an Imaging Passive/Active Neutron System (IPANTM) System at the Savannah River Site (SRS) in South Carolina for the purpose of performing non-destructive assays on contact handled transuranic (CH-TRU) waste in 55-gallon containers. During the four-plus years of operation (May 2001 through August 2005), a vast amount of experience has been gained, with approximately 8950 waste containers assayed. This experience has provided the knowledge base for the evolution of improvements in the assay technique and instrument maintenance and troubleshooting. Additionally, operational experience provides for very reliable characterization of the robustness and applicability of this assay technique for a wide variety of waste streams and provides for assessment of the achievable production output capabilities over a long period of time in a production environment. The assay technique combines passive/active neutron data with gamma energy analysis (GEA) data and acceptable knowledge (AK) data to provide Waste Isolation Pilot Plant (WIPP) compliant quantification of the required nuclides within the waste. These data are incorporated through system software, which automate the data analysis process. However, due to the complex nature of NDA and the potential for a wide variety of interferences, each analysis is reviewed by an Expert Analyst (EA). The software allows the EA to interact with the data analysis process to provide regulatory compliant and defensible results. This technique has evolved with time as a vast array of waste and isotopic compositions have been encountered During 1555 days from the beginning of production operations, the system maintenance log indicates 63 days of downtime due to hardware problems. This translates to an operational availability of 96%. Given the extensive length of time represented by this availability data, 96% availability would represent a very reliable estimate for future applications. Additionally, evolving improvements in troubleshooting techniques and stocking of spare parts could improve the availability. The 8950 production assays performed at SRS falls far short of predicted system throughput, even with allowance for performance of non-production assays such as Quality Assurance (QA) / Quality Control (QC) and WIPP Performance Demonstration Program (PDP) assays. It should be noted that production was significantly altered by site constraints and interruptions in availability of containers. The overall assessment of the instrumentation in conjunction with the assay technique is that this method has a wide range of applicability over a wide range of waste streams. The capability of the EA to interactively interact in the data analysis provides for successful analysis of a wide variety of exception conditions and/or isotopic compositions. The instrument has demonstrated reliable and regulatory compliant operation over a long period of production operations. This assay technique should be suitable for future applications for most TRU or low-level (LLW) waste streams, including remote handled (RH) waste. (authors)

Simpson, A.P.; West, J.M.; Carlton, T.; Peterson, T. [BIL Solutions Inc, 4001 Office Ct Drive no 800, Santa Fe, NM 87507 (United States); Harvill, J. [Washington TRU Solutions LLC (United States)

2006-07-01

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

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

9

Passive and active thermal nondestructive imaging of materials  

Microsoft Academic Search

Thermal non-destructive 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 and structures. In this work, different applications, employing either MWIR or LWIR thermographic testing, as well as passive and\\/or active approaches, depending on the application, concerning the assessment of various materials are

Nicolas P. Avdelidis; Antonia Moropoulou; Darryl P. Almond

2004-01-01

10

Application of nondestructive assay techniques in Kazakstan  

SciTech Connect

As Kazakstan has transitioned from being part of the Soviet Union to a nonweapons state (Treaty of Nonproliferation of Nuclear Weapons [NPT] signatory) under International Atomic Energy Agency (IAEA) inspections, significant changes have been required. Some of these changes have occurred in nuclear material protection, control, and accounting at the four nuclear facility sites in the Republic of Kazakstan. Specifically, the Republic of Kazakstan has changed from relying primarily on a subset of physical protection methods to a graded safeguards approach using a balance of material control, material accounting, and physical protection. Once more intensive material control and accounting procedures and systems are in place, a necessary step is to supply the accounting systems with measured values of high quality. This need can be met with destructive and nondestructive methods. Material control systems can also use qualitative nondestructive assay information as input. This paper will discuss the nondestructive assay techniques and systems the US Department of Energy (DOE) is providing to Kazakstan under both DOE programs and the Cooperative Threat Reduction Act as part of the nuclear material control and accounting upgrades at four facilities in Kazakstan. 4 refs., 6 figs.

Sprinkle, J.K. Jr.; Butler, G.; Collins, M. [and others

1997-11-01

11

Methods and techniques of NDA (nondestructive assay)  

SciTech Connect

Nondestructive assay (NDA) refers to techniques and instruments developed to measure nuclear materials in the many forms in which they occur throughout the fuel cycle. These techniques were first developed to support nuclear safeguards inspections and nuclear material accountability; they are also used extensively for process and quality control. Most accountability measurements are based on analytical chemistry and require that a sample be drawn and analyzed destructively. Destructive analysis can not be applied to many of the product materials found in the fuel cycle, such as fuel rods and assemblies, because of their high monetary value. Also, many waste and scrap materials can not be adequately sampled for destructive analysis because of their heterogenous nature. This situation led to the development of nondestructive analysis techniques. This paper presents an overview of the major NDA techniques and instrumentation in use today. The instrumentation described below is now used frequently by safeguards inspectors and facility operators alike. 19 refs., 18 figs., 4 tabs.

Reilly, T.D.

1988-01-01

12

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

13

Non-Destructive Assay of Curium Contaminated Transuranic Waste Drums  

SciTech Connect

At the Plutonium Facility at Los Alamos National Laboratory, a series of non-destructive assays were performed on five transuranic waste (TRU) drums containing non-plutonium scrap metal that was potentially contaminated with weapons grade plutonium and trace quantities of curium. Typically, waste drums containing metal matrices are assayed for plutonium content using passive neutron coincidence counting techniques. The presence of trace quantities of Cm-244 prevents this type of analysis because of the strong coincidence signal created by spontaneous fission of Cm-244. To discriminate between the plutonium and curium materials present, an active neutron measurement technique was used. A Cf shuffler designed for measurement of uranium bearing materials was calibrated for plutonium in the active mode. The waste drums were then assayed for plutonium content in the shuffler using the active-mode calibration. The curium contamination levels were estimated from the difference between the active-mode measurement in the shuffler and a passive assay in a neutron coincidence counter. Far field gamma-ray measurements were made to identify additional radioactive contaminants and to corroborate the plutonium measurement results obtained from the active-mode assay. This report describes in detail the measurement process used for characterization of these waste drums. The measurement results and the estimated uncertainty will be presented.

Foster, L.A.

1998-11-01

14

Preparation of Pure Plutonium Metal Standards for Nondestructive Assay  

SciTech Connect

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

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

2000-11-01

15

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

16

Parametric effects on nondestructive-assay techniques. Final report  

SciTech Connect

The purpose of the study was to investigate the effect of parameters on nondestructive techniques used for the assay of nuclear material, firstly by an assessment of the current knowledge of parametric effects, and secondly by carrying out experiments on selected parameters. The techniques examined were passive gamma NDA, passive neutron NDA, active NDA, densitometry, and calorimetry. For each technique, operational, intrinsic, and external parameters were identified in a systematic way, and the need for experiments to provide additional information on the effect of selected parameters was also identified. In the area of passive gamma NDA, experiments were conducted to investigate the effect of nonhomogeneity of nuclear material, and a theoretical approach for the description of the effect of nonhomogeneity was developed. The approach can be used as a corrective technique. In the area of passive neutron NDA, experiments were conducted to determine the effect of small amounts of matrix having different moderating and absorbing characteristics. In the area of active NDA, experiments were conducted to investigate the effects of matrix and spatial distribution on coincidence counting in a fission multiplicity detector, and to test methods for minimizing the effects.

Bernatowicz, H.; Borgonovi, G.; Epperson, D.; Glancy, J.; Gozani, T.; Hagan, W.; Harlan, R.; Hope, E.; Horton, W.; McDaniel, T.

1983-08-01

17

A portable nondestructive assay measurement control system  

SciTech Connect

Portable nondestructive assay (NDA) of plutonium processing hoods, solvent extraction columns, glove boxes, filters, and other items is required for both nuclear materials accountability and criticality control purposes. The Plutonium Finishing Plant has hundreds of such items that require routine portable NDA measurement. Previous recordkeeping of NDA measurements consisted of boxes of papers containing results and notebooks containing notes for each item to be measured. If the notes for any item were lost, new measurement parameters had to be calculated for that item. As a result, subsequent measurements could no longer be directly compared with previous results for that item due to possible changes in measurement parameters. The new portable NDA management system keeps all the necessary information in a computerized data base. Technicians are provided with a computer-generated drawing of each item to be measured, which also contains comments, measurement points, measurement parameters, and a form for filling in the raw data. After the measurements are made, the technician uses the computer to calculate and print out the results.

Palmer, M.E.

1984-07-01

18

Preparation of pure neptunium oxide for nondestructive assay standards.  

National Technical Information Service (NTIS)

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 ...

S. L. Yarbro S. L. Dunn S. B. Schreiber

1991-01-01

19

Preparation of pure neptunium oxide for nondestructive assay standards  

Microsoft Academic Search

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 NpOâ and metal were each purified by a different procedure. The NpOâ,

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

1991-01-01

20

Determination of Plutonium Content in Spent Fuel with Nondestructive Assay  

SciTech Connect

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

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

2009-06-30

21

Mobile nondestructive examination and assay instruments  

SciTech Connect

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

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

1988-01-01

22

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

23

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

Microsoft Academic Search

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

D. C. Camp; H. E. Martz

1991-01-01

24

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

25

Nondestructive assay of special nuclear material for uranium fuel-fabrication facilities  

SciTech Connect

A high-quality materials accounting system and effective international inspections in uranium fuel-fabrication facilities depend heavily upon accurate nondestructive assay measurements of the facility`s nuclear materials. While item accounting can monitor a large portion of the facility inventory (fuel rods, assemblies, storage items), the contents of all such items and mass values for all bulk materials must be based on quantitative measurements. Weight measurements, combined with destructive analysis of process samples, can provide highly accurate quantitative information on well-characterized and uniform product materials. However, to cover the full range of process materials and to provide timely accountancy data on hard-to-measure items and rapid verification of previous measurements, radiation-based nondestructive assay (NDA) techniques play an important role. NDA for uranium fuel fabrication facilities relies on passive gamma spectroscopy for enrichment and U isotope mass values of medium-to-low-density samples and holdup deposits; it relies on active neutron techniques for U-235 mass values of high-density and heterogeneous samples. This paper will describe the basic radiation-based nondestructive assay techniques used to perform these measurements. The authors will also discuss the NDA measurement applications for international inspections of European fuel-fabrication facilities.

Smith, H.A. Jr. [Los Alamos National Lab., NM (United States); Schillebeeckx, P. [European Commission Joint Research Center, Ispra (Italy)

1997-08-01

26

Experience of developing an integrated nondestructive assay system  

SciTech Connect

A consortium of national laboratories is collaborating with the Savannah River Plant to develop an integrated system of state-of-the-art nondestructive assay (NDA) instrumentation to provide nuclear materials accounting and process control information for a new plutonium scrap recovery facility. Individual microcomputer-based instruments report assay results to an instrument control computer (ICC). The ICC, in turn, is part of a larger computer network that includes computers that perform process control and nuclear materials accounting functions. The experience in developing the integrated NDA system, the design, and the testing are discussed.

Hsue, S.T.; Baker, M.P.

1987-01-01

27

Nondestructive assay of sphere-pac fuel rods  

SciTech Connect

Nondestructive assay (NDA) methods were studied for application to sphere-pac fuel with a high gamma ray background. It was decided that the NDA method selected should be capable of measuring total fissile content of each fuel rod as well as determining the axial fissile distribution because assay techniques that employ detection of spontaneous or induced gamma ray emission are not practicable because of the high gamma ray background of candidate fuels. Therefore, methods employing neutron detection were studied for use with sphere-pac fuel rods.

Allen, E.J.; Angelini, P.; Baker, S.P.; Heck, J.L.; Mack, J.E.

1981-03-01

28

Measurement control: Principles and practice as applied to nondestructive assay  

SciTech Connect

This paper discusses the principles and practice of measurement control for nondestructive assay (NDA) instruments. The NDA is not always blessed with the highly controlled samples that are assumed in the analytical laboratory. This adversely affects the use and applicability of the historical error information from instrument stability checks to estimate measurement uncertainties for the broad range of sample characteristics presented to most NDA instruments. This paper emphasizes the methods used to perform instrument stability checks and discusses the resulting uncertainty information that can be derived from these measurements. 4 refs., 2 figs., 2 tabs.

Sampson, T.E.

1991-01-01

29

First-year evaluation of a nondestructive assay system for the examination of ORNL TRU waste  

SciTech Connect

The Oak Ridge National Laboratory has been selected as the demonstration site for a new transuranic neutron assay system (NAS) developed at the Los Alamos National Laboratory. In addition, in order to meet specific ORNL program objectives, an upgraded segmented gamma-ray drum scanner has been integrated into the nondestructive assay (NDA) system to serve as a radioisotope identifier and as a quantitative assay backup to the NAS. A verification study, wherein selected waste drums will be emptied into glove boxes and their contents sampled and subsequently gamma-ray assayed, will take place in FY 1984. Results will be compared to those obtained from the NDA techniques. The NAS uses pulsed-neutron interrogation (differential- dieaway technique) and passive neutron measurements to determine fissile component and an upper-limit estimate of the total TRU activity contained in each waste drum. Of the 171 waste drums assayed to date, nine drums were determined to contain less than 10 nCi/g TRU isotopes. An additional number of drums (approximately 20%) are expected to be categorized as non-TRU, which is presently defined as less than 100 nCi/g TRU concentration. This requires a detailed analysis of the data which includes waste matrix compensation, systematic qualitative and quantitative gamma-ray analyses, and interpretation of neutron multiplicity data. Reproducibility of the active assay measurements on a single waste drum indicate agreement to +-3% relative error. 14 references, 24 figures, 8 tables.

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

1984-04-01

30

The use of non-destructive passive neutron measurement methods in dismantling and radioactive waste characterization  

SciTech Connect

The cleaning up and dismantling of nuclear facilities lead to a great volume of technological radioactive wastes which need to be characterized in order to be sent to the adequate final disposal or interim storage. The control and characterization can be performed with non-destructive nuclear measurements such as gamma-ray spectrometry. Passive neutron counting is an alternative when the alpha-gamma emitters cannot be detected due to the presence of a high gamma emission resulting from fission or activation products, or when the waste matrix is too absorbing for the gamma rays of interest (too dense and/or made of high atomic number elements). It can also be a complement to gamma-ray spectrometry when two measurement results must be confronted to improve the confidence in the activity assessment. Passive neutron assays involve the detection of spontaneous fission neutrons emitted by even nuclides ({sup 238}Pu, {sup 240}Pu, {sup 242}Pu, {sup 242}Cm, {sup 244}Cm...) and neutrons resulting from ({alpha}, n) reactions with light nuclides (O, F, Be...). The latter is conditioned by the presence of high {alpha}-activity radionuclides ({sup 234}U, {sup 238}Pu, {sup 240}Pu, {sup 241}Am...) and low-Z elements, which depends on the chemical form (metallic, oxide or fluorine) of the plutonium or uranium contaminant. This paper presents the recent application of passive neutron methods to the cleaning up of a nuclear facility located at CEA Cadarache (France), which concerns the Pu mass assessment of 2714 historic, 100 litre radioactive waste drums produced between 1980 and 1997. Another application is the dismantling and decommissioning of an uranium enrichment facility for military purposes, which involves the {sup 235}U and total uranium quantifications in about a thousand, large compressors employed in the gaseous diffusion enrichment process. (authors)

Jallu, F.; Allinei, P. G. [CEA, DEN, Cadarache, Nuclear Measurement Laboratory, F-13108 Saint-Paul-lez-Durance (France); Bernard, P.; Loridon, J. [CEA, DEN, Cadarache, Nuclear Measurement Laboratory, F-13108 Saint-Paul-lez-Durance (France); Soyer, P.; Pouyat, D. [CEA, DEN, Marcoule, DPAD, F-30207 Bagnols-sur-Ceze Cedex (France); Torreblanca, L. [CEA, DEN, Cadarache, LMDE, F-13108 Saint-Paul-lez-Durance (France); Reneleau, A. [AREVA NC, Pierrelatte, DDAC/ESD, BP16, F-26701 Pierrelatte Cedex (France)

2011-07-01

31

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

32

Nondestructive assay of uranium enrichment with gamma rays  

SciTech Connect

An instrument has been developed and tested for nondestructive assay of /sup 235/U enrichment of uranium oxide powder contained in sealed 1-gallon cans. Enrichment (epsilon) is measured from the count rate (D) of the 186 keV ..gamma..-ray of /sup 235/U, using an HPGe ..gamma..-detector. A theoretical correlation of epsilon vs D agrees well with the calibration measurements and provides guidelines for applicability. Measurements for 97 can samples with epsilon = 56 to 60 enrichment percent (e%) /sup 235/U demonstrated accuracy of approx. 0.2 e% /sup 235/U and precision of approx. 0.4 e% /sup 235/U, with 10-minute count times. A microcomputer simplifies operator requirements and provides on-line enrichment results.

Winn, W.G.

1983-03-01

33

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

SciTech Connect

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

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

2012-03-01

34

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

SciTech Connect

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

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

1991-11-12

35

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

SciTech Connect

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

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

1998-09-01

36

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

37

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

38

Design and evaluation of a nondestructive fissile assay device for HTGR fuel samples  

Microsoft Academic Search

Nondestructive assay of fissile material plays an important role in nuclear fuel processing facilities. Information for product quality control, plant criticality safety, and nuclear materials accountability can be obtained from assay devices. All of this is necessary for a safe, efficient, and orderly operation of a production plant. Presented here is a design description and an operational evaluation of a

S. R. McNeany; R. W. Knoll; J. D. Jenkins

1979-01-01

39

Evaluation of nondestructive assay characterization methods for pipe-over-pack containers  

SciTech Connect

Nondestructive assay (NDA) measurements of Transuranic (TRU) waste at Los Alamos National Laboratory (LANL) packed in Pipe-Over-Pack Containers or POC's exhibit a number of complexities. The POC is highly attenuating to both gamma rays and neutrons which presents a difficult waste matrix for correct quantification of material in the container. Also, chemical and matrix properties of the Pu contaminated waste in the POCs that may affect the measurement result are generally unknown in advance of the measurement. Currently there are a number of POC containers at LANL that require evaluation for shipment to the Waste Isolation Pilot Plant (WIPP) in Carlsbad, NM. At LANL, a single instrument has been used to explore the appropriateness of both passive neutron and quantitative gamma ray methods for measuring POC's. The instrument, a High Efficiency Neutron Counter (HENC) with an integrated high purity germanium detector incorporates both passive neutron and high resolution gamma counting capabilities. The passive neutron approach uses the Reals coincidence count rate to establish plutonium mass and other parameters of interest for TRU waste. The quantitative gamma ray method assumes a homogeneous distribution of matrix and source material and assays the drum with a calibration based on the known density of the matrix. Both methods are supplemented by a simultaneous gamma isotopic measurement using Multi-Group Analysis (MGA) software to determine the plutonium isotopic composition. If MGA fails to provide a viable isotopic result Fixed energy Response function Analysis with Multiple efficiencies (FRAM) could be used to replace MGA results. Acceptable knowledge (AK) may also be used in certain instances. This report will discuss the two measurement methods in detail for POC analysis. Included in the discussion will be descriptions of the setup parameters and calibration techniques for the instrument. A number of test measurements have been performed to compare HENC data with certified safeguards data. Empty POCs loaded with known sources have also been measured to determine the viability of the technique. Finally, a brief discussion of the conclusions that can be drawn from the tests will be offered. (authors)

Stanfield, S.B.; Wachter, J.R.; Cramer, D.L. [Canberra Instruments Inc., Meriden, CT (United States)

2007-07-01

40

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

41

Portable calorimeter system for nondestructive assay of mixed-oxide fuels  

Microsoft Academic Search

Calorimetric assay provides a precise, nondestructive method to determine sample Pu content based on the heat emitted by decaying radionuclides. This measurement, in combination with a gamma-spectrometer analysis of sample isotopic content, yields the total sample Pu mass. The technique is applicable to sealed containers and is essentially independent of sample matrix configuration and elemental composition. Conventional calorimeter designs employ

C. T. Roche; R. B. Perry; R. N. Lewis; E. A. Jung; J. R. Haumann

1978-01-01

42

Guidance on meeting DOE order requirements for traceable nondestructive assay measurements  

SciTech Connect

Purpose of this guide is to facilitate accuracy and precision of nondestructive assay measurements through improvement of the materials and process of traceability. This document provides DOE and its contractor facilities with guidance to establish traceability to the national measurement base for site-prepared NDA working reference materials.

Not Available

1994-05-01

43

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

Microsoft Academic Search

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

2001-01-01

44

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

Microsoft Academic Search

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

2001-01-01

45

Integrated nondestructive assay solutions for plutonium measurement problems of the 21st century  

Microsoft Academic Search

The authors describe automated and integrated nondestructive assay (NDA) systems configured to measure many of the materials that will be found in the Department of Energy complex in the dismantlement, disposition, residue stabilization, immobilization, and mixed oxide fuel programs. These systems are typified by the Advanced Recovery and Integrated Extraction System NDA system which is under construction at Los Alamos

T. E. Sampson; T. L. Cremers

1997-01-01

46

Integrated nondestructive assay solutions for plutonium measurement problems of the 21st century  

Microsoft Academic Search

The authors describe automated and integrated NDA systems configured to measure many of the materials that will be found in the DOE complex in the dismantlement, disposition, residue stabilization, immobilization, and MOX fuel programs. These systems are typified by the ARIES (Advanced Recovery and Integrated Extraction System) nondestructive assay system which is under construction at Los Alamos to measure the

T. E. Sampson; T. L. Cremers

1997-01-01

47

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

48

Nondestructive assay of spent boiling water reactor fuel by active neutron interrogation  

Microsoft Academic Search

Spent boiling water reactor (BWR) fuel from Dresden I was assayed for total fissile mass, using the active neutron interrogation method. The nondestructive assay (NDA) system used has four Sb-Be sources for interrogation of the fuels; the induced fission neutrons from the fuel are counted by four lead-shielded methane-filled proportional counters biased above the energy of the source neutrons. Spent

E. D. Blakeman; C. W. Ricker; G. L. Ragan; F. C. Difilippo; G. G. Slaughter

1981-01-01

49

System for nondestructive assay of spent fuel subassemblies: comparison of calculations and measurements  

Microsoft Academic Search

A nondestructive assay system was developed for determining the total fissile content of spent fuel subassemblies at the head end of a reprocessing plant. The system can perform an assay in 20 min with an uncertainty of <5%. Antimony-beryllium neutrons interrogate the subassemblies, and proton recoil counters detect the resulting fission neutrons. Pulse-height discrimination differentiates between the low-energy interrogation neutrons

G. L Ragan; C. W. Ricker; M. M. Chiles; D. T. Ingersoll; G. G. Slaughter; L. R. Williams

1979-01-01

50

SWEPP PAN assay system uncertainty analysis: Passive mode measurements of graphite waste  

SciTech Connect

The Idaho National Engineering and Environmental Laboratory is being used as a temporary storage facility for transuranic waste generated by the U.S. 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. To this end a modified statistical sampling and verification approach has been developed to determine the total uncertainty of a PAN measurement. In this approach the total performance of the PAN nondestructive assay system is simulated using computer models of the assay system and the resultant output is compared with the known input to assess the total uncertainty. 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 passive mode measurements of weapons grade plutonium-contaminated graphite molds contained in 208 liter drums (waste code 300). The validity of the simulation approach is verified by comparing simulated output against results from measurements using known plutonium sources and a surrogate graphite waste form drum. For actual graphite waste form conditions, a set of 50 cases covering a statistical sampling of the conditions exhibited in graphite wastes was compiled using a Latin hypercube statistical sampling approach.

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

1997-07-01

51

Field experience with a mobile tomographic nondestructive assay system  

SciTech Connect

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

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

1995-12-01

52

RoboCal: An automated nondestructive assay system  

SciTech Connect

The manager of a facility handling special nuclear material (SNM) is caught in a squeeze between increased state and federal regulations and tighter funding. RoboCal uses a robot to manipulate canisters containing SNM to lower worker radiation exposure and to provide increased utilization of expensive assay equipment. In addition, it helps with accountability and material tracking. It consists of a hierarchical network of more than a dozen computers and provides a single point of contact for the user to accomplish multiple assays.

Staley, H.C.; Hollen, R.M.; Bonner, C.A.

1990-01-01

53

Passive nondestructive burnup monitoring of MNSR irradiated fuel by measuring photoneutrons produced within fission products.  

PubMed

A passive nondestructive method for monitoring of Syrian miniature neutron source reactor (MNSR) fuel burnup is introduced. The inner irradiation site design inside the Be reflector was exploited to measure the generated photoneutrons induced by fission products hard gamma radiation in the subcritical state. The photoneutron flux was measured using gold foils as a function of cooling time and operation power. For cooling time ranges between 10 and 25d, experiments show that (140)Ba is the extremely dominating inducer of photoneutrons and the measured flux is proportional to the accumulated (140)Ba. This result forms a new method base for MNSR fuel burnup monitoring. It might be used also as a safeguards technique to check the operator declared information. PMID:19620012

Haddad, Kh

2009-06-26

54

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

SciTech Connect

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

Mace, Emily K.; Smith, Leon E.

2011-10-01

55

MONTE CARLO ERROR ESTIMATION APPLIED TO NONDESTRUCTIVE ASSAY METHODS  

SciTech Connect

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

R. ESTEP; ET AL

2000-06-01

56

Integrated nondestructive assay solutions for plutonium measurement problems of the 21st century  

SciTech Connect

The authors describe automated and integrated nondestructive assay (NDA) systems configured to measure many of the materials that will be found in the Department of Energy complex in the dismantlement, disposition, residue stabilization, immobilization, and mixed oxide fuel programs. These systems are typified by the Advanced Recovery and Integrated Extraction System NDA system which is under construction at Los Alamos National Laboratory to measure the outputs of a weapon component dismantlement system.

Sampson, T.E.; Cremers, T.L.

1997-12-01

57

Nondestructive assay applied to the decommissioning of a former plutonium fuel fabrication facility  

Microsoft Academic Search

In July of 1987, EcoTak, Inc., was contracted to provide technical support and project management for the decommissioning of the Nuclear Fuel Services, Inc., mixed-oxide fuel fabrication facility. In February of 1989, Pajarito Scientific Corporation was contracted to design and provide a comprehensive nondestructive assay (NDA) system consisting of five separation NDA stations. This five-station NDA system provides on-line plutonium

M. L. West; R. A. Hunt; R. E. Allman; J. T. Caldwell; T. H. Kuckertz; M. R. Newell

1991-01-01

58

Integrated nondestructive assay solutions for plutonium measurement problems of the 21st century  

SciTech Connect

The authors describe automated and integrated NDA systems configured to measure many of the materials that will be found in the DOE complex in the dismantlement, disposition, residue stabilization, immobilization, and MOX fuel programs. These systems are typified by the ARIES (Advanced Recovery and Integrated Extraction System) nondestructive assay system which is under construction at Los Alamos to measure the outputs of a weapon component dismantlement system.

Sampson, T.E.; Cremers, T.L.

1997-08-01

59

Integrated nondestructive assay system for a new plutonium scrap recovery facility  

SciTech Connect

A consortium of laboratories is collaborating with the Savannah River Plant to develop an integrated system of state-of-the-art nondestructive assay (NDA) instrumentation to provide nuclear materials accounting and process control information for a new plutonium scrap recovery facility. Individual microcomputer-based instruments report assay results to an Instrument Control Computer (ICC). The ICC, in turn, is part of a larger computer network that includes computers that perform process control and nuclear materials accounting functions. Integrated system design considerations, integral testing, and individual instrument measurement functions are discussed. 3 refs., 3 figs., 1 tab.

Baker, M.

1985-01-01

60

Nondestructive assay of spent boiling water reactor fuel by active neutron interrogation  

SciTech Connect

Spent boiling water reactor (BWR) fuel from Dresden I was assayed for total fissile mass, using the active neutron interrogation method. The nondestructive assay (NDA) system used has four Sb-Be sources for interrogation of the fuels; the induced fission neutrons from the fuel are counted by four lead-shielded methane-filled proportional counters biased above the energy of the source neutrons. Spent fuel rods containing 9 kg of heavy metal were chopped into 5-cm segments and loaded into three 1-liter cans. The three cans were assayed in seven combinations of one, two, or three cans, enabling an evaluation of the precision and accuracy of the NDA system for different amounts of fissile material. The fissile mass in each combination was determined by comparing the induced-fission-neutron counts with the counts obtained from a known standard comprising chopped segments of unirradiated Dresden fuel. These masses were compared to the masses determined by chemical analyses of the spent fuel. The results from the nondestructive assays agreed with results from the chemical analyses to within 2 to 3%. Similar agreement was obtained when two combinations of canned spent fuel were used as standards for the nondesctuctive assays. The assay of BWR spent fuel served as a test of the NDA system which was developed at the Oak Ridge National Laboratory for the assay of spent liquid metal fast breeder reactor (LMFBR) fuel subassemblies at the heat-end of a reprocessing plant. Results of previous experiments and calculations reported earlier using simulated LMFBR fuel subassemblies indicated that the NDA system can measure the fissile masses of spent fuel subassemblies to within an accuracy of 3%. Results of the assays of spent BWR fuel reported herein support this conclusion.

Blakeman, E.D.; Ricker, C.W.; Ragan, G.L.; Difilippo, F.C.; Slaughter, G.G.

1981-01-01

61

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

2013-10-15

62

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

63

Investigations of the performance and nondestructive assay applications of the EMR/Schlumberger neutron generator  

SciTech Connect

Los Alamos and EMR/Schlumberger, are jointly investigating nondestructive assay applications using the EMR neutron generator system. This system is based on the instrument fielded by Schlumberger for oil well logging. This technology has been adapted into a complete system and package, which is intended for a variety of above-ground applications such as basic research, nuclear waste assay, activation analysis, and nuclear material analysis in both field and laboratory. The system has certain features, which have made it attractive for applications in the Los Alamos safeguards program. We will describe the neutron generator system and the over-all experimental equipment that will be used to explore some of these applications. We will also describe the general performance and some specific performance tests conducted at Los Alamos.

Pickrell, M.M. [Los Alamos National Lab., NM (United States); Mahdavi, M.; Pfutzner, H. [EMR/Schlumberger, Princeton, NJ (United States)

1993-08-01

64

Gamma ray scanner systems for nondestructive assay of heterogeneous waste barrels  

SciTech Connect

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

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

1997-08-01

65

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

NASA Astrophysics Data System (ADS)

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

Wu, Cheng-Wei

1997-11-01

66

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

67

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

68

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

69

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

70

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

SciTech Connect

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

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

2010-08-04

71

Status Report on the Passive Neutron Enrichment Meter (PNEM) for UF6 Cylinder Assay  

SciTech Connect

The Passive Neutron Enrichment Meter (PNEM) is a nondestructive assay (NDA) system being developed at Los Alamos National Laboratory (LANL). It was designed to determine {sup 235}U mass and enrichment of uranium hexafluoride (UF{sub 6}) in product, feed, and tails cylinders (i.e., 30B and 48Y cylinders). These cylinders are found in the nuclear fuel cycle at uranium conversion, enrichment, and fuel fabrication facilities. The PNEM is a {sup 3}He-based neutron detection system that consists of two briefcase-sized detector pods. A photograph of the system during characterization at LANL is shown in Fig. 1. Several signatures are currently being studied to determine the most effective measurement and data reduction technique for unfolding {sup 235}U mass and enrichment. The system collects total neutron and coincidence data for both bare and cadmium-covered detector pods. The measurement concept grew out of the success of the Uranium Cylinder Assay System (UCAS), which is an operator system at Rokkasho Enrichment Plant (REP) that uses total neutron counting to determine {sup 235}U mass in UF{sub 6} cylinders. The PNEM system was designed with higher efficiency than the UCAS in order to add coincidence counting functionality for the enrichment determination. A photograph of the UCAS with a 48Y cylinder at REP is shown in Fig. 2, and the calibration measurement data for 30B product and 48Y feed and tails cylinders is shown in Fig. 3. The data was collected in a low-background environment, meaning there is very little scatter in the data. The PNEM measurement concept was first presented at the 2010 Institute of Nuclear Materials Management (INMM) Annual Meeting. The physics design and uncertainty analysis were presented at the 2010 International Atomic Energy Agency (IAEA) Safeguards Symposium, and the mechanical and electrical designs and characterization measurements were published in the ESARDA Bulletin in 2011.

Miller, Karen A. [Los Alamos National Laboratory; Swinhoe, Martyn T. [Los Alamos National Laboratory; Menlove, Howard O. [Los Alamos National Laboratory; Marlow, Johnna B. [Los Alamos National Laboratory

2012-05-02

72

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

73

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

SciTech Connect

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

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

2010-08-08

74

Proficiency test for non-destructive assay of 220 liter radioactive waste drums by gamma assay systems  

SciTech Connect

The European Network of Testing Facilities for the Quality Checking of Radioactive Waste Packages (ENTRAP) initiated a feasibility study on how to organize in the most cost effective way an international proficiency tests for non-destructive, gamma-ray based, assay of 220 liter radioactive waste drums in the European Union at a regular time interval of 2 or 3 years. This feasibility study addresses all aspects of proficiency testing on radioactive waste packages including the design of a commonly accepted reference 220 liter drum. This design, based on the international response on a send out questionnaire, includes matrixes, radioactive sources; a solution to overcome the tedious and expensive international transport costs of real or even simulated waste packages, general cost estimation for the organization of, and the participation in the proficiency test. The proposed concept for the proficiency testing and the estimated costs are presented. The participation costs of the first proficiency test are mainly determined by the manufacturing of the non-radioactive 220 liter drum ({+-} 55%). Applied reference sources, transport of the drum and reference sources and participation costs in the proficiency test contribute each about {+-} 15%. (authors)

Van Velzen, L.P.M. [Nuclear Research and consultancy Group - NRG, PO Box 25, NL-1755 ZG Petten (Netherlands); Bruggeman, M. [SCK-CEN, Mol (Belgium); Botte, J. [Belgoprocess, Gravenstraat 73 - 2480 Dessel (Belgium)

2007-07-01

75

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

76

Methods for nondestructive assay holdup measurements in shutdown uranium enrichment facilities  

SciTech Connect

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

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

1991-09-01

77

Gamma ray scanner systems for nondestructive assay of heterogeneous waste barrels  

SciTech Connect

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

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

1997-03-25

78

NON-DESTRUCTIVE ASSAY OF CE-144 IN PRESENCE OF TRANSURANIC WASTE  

SciTech Connect

The Ce- 144 isotope has been identified as a radionuclide produced in certain Los Alamos National Laboratory plutonium waste streams and thus may need to be quantified when present in reportable quantities for shipment to the Waste Isolation Pilot Plant (WIPP). The most intense gamma ray from Ce-144 was found to be the 133.53 keV peak. At this energy, there were no interfering plutonium or plutonium daughter gainma rays. Furthermore, it was determined that there were no interferences produced by Ce- 144 or its progenies that could degrade the plutonium isotopic analysis. At 5% of the total activity per gram of plutonium, the reportable limit, the Ce-144 peak at 133.53 keV will remain above the primary plutonium peak (129.3 keV) for approximately 7 years and remain quantifiable for at least 12 to 13 years from the time the isotope was chemically separated. It is therefore concluded that Ce-144 will be quantifiable whenever it exceeds 5% of the total activity per gram of plutonium, and will not interfere with the non-destructive assay of plutonium isotopic compositions.

Los Alamos National Laboratory

2001-01-01

79

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

SciTech Connect

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

Johnson, R.E.

1998-07-06

80

A New Facility For Non-Destructive Assay With A Time-Tagged {sup 252}Cf Source  

SciTech Connect

A new facility for Non-Destructive Assay based on a time-tagged {sup 252}Cf spontaneous fission source is now in operation at the Padova University. The system is designed to analyze samples with dimensions on the order of 20x20 cm{sup 2}, the material recognition being obtained by measuring simultaneously transmission of neutrons and gamma rays as a function of energy.

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

2011-06-01

81

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: (1) The WRAP waste stream debris is from the Hanford Plutonium Finishing Plant's process lines, primarily combustible materials. (2) Plutonium analysis range is from the minimum detectable concentration (MDC), Reference 6, to 200 grams (g). (3) The GEA system calibration density ranges from 0.013 g/cc to 1.6 g/cc. (4) PDP Plutonium drum densities were evaluated from 0.065 g/cc to 0.305 g/cc. (5) PDP Plutonium source weights ranged from 0.030 g to 318 g, in both empty and combustibles matrix drums. (6) The GEA system design density correction mass absorption coefficient table (MAC) is Lucite, a material representative of combustible waste. (7) 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.

2000-10-20

82

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

83

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) measurement of TRU waste containers is one of the methods used for waste characterization. Various programs exist to ensure the validity of waste characterization data; all of these cite the need for clearly defied knowledge of the uncertainties associated with any measurements performed. 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 to the TMU is analyzed, and a final method is given for determining the TMU for NDA measurements at WRAP. A brief description of the data flow paths for the analytical process is also included in this report. As more data becomes available, and WRAP gains in operational experience, this report will be reviewed semi-annually and updated as necessary.

CANTALOUB, M.G.

2002-01-02

84

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

SciTech Connect

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

Becker, G.K.

1997-01-01

85

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

SciTech Connect

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

Carlsbad Field Office

2001-01-31

86

Neutron coincidence imaging for active and passive neutron assays  

Microsoft Academic Search

Neutron multiplicity assay algorithms for ²°Pu assume a point source of fission neutrons that are detected in a single detector channel. The ²°Pu in real waste, however, is more likely to be distributed throughout the container in some random way. For different reasons, this leads to significant errors when using either multiplicity or simpler coincidence analyses. Reduction of these errors

R. J. Estep; G. S. Brunson; S. G. Melton

2001-01-01

87

Three-energy gamma-ray absorptiometer (TEGA) for nondestructive assay of plutonium and uranium in solution  

SciTech Connect

An experimental approach for the nondestructive characterization of plutonium and uranium solutions is presented. The technique relies on the transmission of photons of three different properly chosen energies, and allows an independent and simultaneous determination of plutonium and uranium by the different absorption of the two elements in the range of K-edge energies. The performances achievable have been evaluated through measurement of a set of solutions using the hardware of the compact K-edge densitometer. The plutonium and uranium concentrations ranged from 50 to 150 g/l. In this concentration range, the relative precision is below 3.0% for uranium assay and below 6% for plutonium assay. Further improvements of the performances of the technique are discussed. 3 refs., 9 figs., 1 tab.

Aparo, M.

1986-01-01

88

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

SciTech Connect

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

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

1992-01-01

89

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

SciTech Connect

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

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

1992-06-01

90

A state-of-the-art passive gamma-ray assay system  

SciTech Connect

We report details of the development of a high-accuracy, high-precision system for the non-destructive assay of /sup 235/U in solution. The system can measure samples with concentrations ranging from 0.0001 to 500 g /sup 235/U/l using 200-ml samples at low concentrations, 30-ml samples at high concentrations, and 1000-s measurement times. The accuracy and precision goals of 0.1% were essentially attained for concentrations above 100 g/l. This at-line system, designed for a production plant environment, represents a significant improvement in the state of the art.

Sampson, T.E.; Parker, J.L.; Cowder, L.R.; Kern, E.A.; Garcia, D.L.; Ensslin, N.

1987-01-01

91

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

SciTech Connect

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

Parker, J.L.

1984-08-01

92

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

SciTech Connect

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

Parker, J.L.

1986-11-01

93

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

94

A new facility for non-destructive assay using a 252Cf source.  

PubMed

A new laboratory facility for non-destructive analysis (NDA) using a time-tagged (252)Cf source is presented. The system is designed to analyze samples having maximum size of about 20 × 25 cm(2), the material recognition being obtained by measuring simultaneously total and energy dependent transmission of neutrons and gamma rays. The equipment technical characteristics and performances of the NDA system are presented, exploring also limits due to the sample thickness. Some recent applications in the field of cultural heritage are presented. PMID:23276691

Stevanato, L; Caldogno, M; Dima, R; Fabris, D; Hao, Xin; Lunardon, M; Moretto, S; Nebbia, G; Pesente, S; Pino, F; Sajo-Bohus, L; Viesti, G

2012-12-06

95

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

96

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

NASA Astrophysics Data System (ADS)

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

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

2011-09-01

97

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

98

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

SciTech Connect

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

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

2010-09-15

99

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

100

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

101

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

SciTech Connect

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

Difilippo, F.C.

1999-10-01

102

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

103

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

104

Stress-Induced Changes in Optical Properties, Pigment and Fatty Acid Content of Nannochloropsis sp.: Implications for Non-destructive Assay of Total Fatty Acids  

Microsoft Academic Search

In order to develop a practical approach for fast and non-destructive assay of total fatty acid (TFA) and pigments in the\\u000a biomass of the marine microalga Nannochloropsis sp. changes in TFA, chlorophyll, and carotenoid contents were monitored in parallel with the cell suspension absorbance.\\u000a The experiments were conducted with the cultures grown under normal (complete nutrient f\\/2 medium at 75 ?mol

Alexei Solovchenko; Inna Khozin-Goldberg; Lee Recht; Sammy Boussiba

2011-01-01

105

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

SciTech Connect

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

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

2008-07-01

106

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

107

PROMETHEE: An Alpha Low Level Waste Assay System Using Passive and Active Neutron Measurement Methods  

SciTech Connect

The development of a passive-active neutron assay system for alpha low level waste characterization at the French Atomic Energy Commission is discussed. Less than 50 Bq[{alpha}] (about 50 {mu}g Pu) per gram of crude waste must be measured in 118-l 'European' drums in order to reach the requirements for incinerating wastes. Detection limits of about 0.12 mg of effective {sup 239}Pu in total active neutron counting, and 0.08 mg of effective {sup 239}Pu coincident active neutron counting, may currently be detected (empty cavity, measurement time of 15 min, neutron generator emission of 1.6 x 10{sup 8} s{sup -1} [4{pi}]). The most limiting parameters in terms of performances are the matrix of the drum - its composition (H, Cl...), its density, and its heterogeneity degree - and the localization and self-shielding properties of the contaminant.

Passard, Christian [French Atomic Energy Commission, C.E.A. Cadarache (France); Mariani, Alain [French Atomic Energy Commission, C.E.A. Cadarache (France); Jallu, Fanny [French Atomic Energy Commission, C.E.A. Cadarache (France); Romeyer-Dherbey, Jacques [French Atomic Energy Commission, C.E.A. Cadarache (France); Recroix, Herve [French Atomic Energy Commission, C.E.A. Cadarache (France); Rodriguez, Michel [French Atomic Energy Commission, C.E.A. Cadarache (France); Loridon, Joel [French Atomic Energy Commission, C.E.A. Cadarache (France); Denis, Caroline [French Atomic Energy Commission, C.E.A. Cadarache (France); Toubon, Herve [COGEMA (France)

2002-12-15

108

Neutron coincidence counting based on time interval analysis with one- and two-dimensional Rossi-alpha distributions: an application for passive neutron waste assay  

Microsoft Academic Search

Neutron coincidence counting is commonly used for the non-destructive assay of plutonium bearing waste or for safeguards verification measurements. A major drawback of conventional coincidence counting is related to the fact that a valid calibration is needed to convert a neutron coincidence count rate to a 240Pu equivalent mass (240Pueq). In waste assay, calibrations are made for representative waste matrices

M. Bruggeman; P. Baeten; W De Boeck; R. Carchon

1996-01-01

109

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

110

The dosing determines mutagenicity of hydrophobic compounds in the Ames II assay with metabolic transformation: passive dosing versus solvent spiking.  

PubMed

The Ames II bacterial mutagenicity assay is a new version of the standard Ames test for screening chemicals for genotoxic activity. However, the use of plastic micro-titer plates has drawbacks in the case of testing hydrophobic mutagens, since sorptive and other losses make it difficult to control and define the exposure concentrations, and they reduce availability for bacterial uptake or to the S9 enzymes. With passive dosing, a biocompatible polymer such as silicone is loaded with the test compound and acts as a partitioning source. It compensates for any losses and results in stable freely dissolved concentrations. Passive dosing using silicone O-rings was applied in the Ames II assay to measure PAH mutagenicity in strains TA98 and TAMix - a mixture of six different bacterial strains detecting six different base-pair substitutions - after metabolic activation by S9. Initially, 10 PAHs were tested with passive dosing from saturated O-rings, aiming at levels in the test medium close to aqueous solubility. Fluoranthene, pyrene and benzo(a)pyrene were mutagenic in both TA98 and TAMix, whereas benz(a)anthracene was mutagenic in TA98 only. The concentration-dependent mutagenic activity of benzo(a)pyrene was then compared for passive dosing and solvent spiking. With spiking, nominal concentrations greatly exceeded aqueous solubility before mutagenicity was observed, due to sorptive losses and limiting dissolution kinetics. In contrast, the passive dosing concentration-response curves were more reproducible, and shifted towards lower concentrations by several orders of magnitude. This study raises fundamental questions about how to introduce hydrophobic test substances in the Ames II assay with biotransformation, since the measured mutagenicity not only depends on the compound potency but also on its supply, sorption and consumption during the assay. PMID:22989744

Smith, Kilian E C; Heringa, Minne B; Uytewaal, Marijan; Mayer, Philipp

2012-09-16

111

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

112

Comparison of three immunoglobulin G assays for the diagnosis of failure of passive transfer of immunity in neonatal alpacas.  

PubMed

Measurement of serum immunoglobulin G (IgG) is used for the assessment of passive transfer of immunity in neonatal crias, with an IgG concentration <10 g/l being suggestive of failure of passive transfer (FPT). The purpose of the current study was to determine whether 3 commercially available immunologic assays yielded comparable results for IgG in alpacas. Serum samples from 91 alpacas were used and were stored frozen until batch analysis on the same day with the 3 assays. Immunoglobulin G was measured by radial immunodiffusion (RID) and 2 immunoturbidimetric (IT) assays (IT1, configured for automated chemistry analyzers; IT2, a point-of-care test). Median IgG concentrations were significantly different between the 3 assays, with the RID (median: 15 g/l) and IT1 (median: 16 g/l) assays, which used the same standard, yielding significantly higher IgG values than IT2 (median: 11 g/l). Results indicated a diagnostic discordance in 1-17% of samples at an IgG threshold of 10 g/l. Protein electrophoresis revealed that the RID and IT1 standard contained mostly albumin (>60%), whereas the IT2 standard consisted of beta and gamma globulins. The discrepant results between assays IT1 and IT2 were eliminated when the same standard was used (IT1: median 11 g/l; IT2: 10 g/l; n = 19 and 17, respectively). The IT1 assay had the highest precision, while the RID assay had the lowest. The results indicate that camelid IgG measurement is highly dependent on the assay standard and is not directly comparable between assays, potentially resulting in underdiagnosis of FPT in some crias. PMID:23345272

Pinn, Toby L; Gagliardo, Lucille F; Purdy, Steve R; Appleton, Judith A; Stokol, Tracy

2013-01-01

113

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

2011-02-10

114

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

Microsoft Academic Search

This paper deals with the application of non-destructive neutron measurement methods to control and characterize 200l radioactive waste drums filled with a concrete matrix. Due to its composition, and particularly to hydrogen, concrete penalizes the use of such methods to quantify uranium (U) and plutonium (Pu) components, which are mainly responsible of the ?-activity of the waste. The determination of

F. Jallu; C. Passard; E. Brackx

2011-01-01

115

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

116

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.

117

Stress-induced changes in optical properties, pigment and fatty acid content of Nannochloropsis sp.: implications for non-destructive assay of total fatty acids.  

PubMed

In order to develop a practical approach for fast and non-destructive assay of total fatty acid (TFA) and pigments in the biomass of the marine microalga Nannochloropsis sp. changes in TFA, chlorophyll, and carotenoid contents were monitored in parallel with the cell suspension absorbance. The experiments were conducted with the cultures grown under normal (complete nutrient f/2 medium at 75 ?mol PAR photons/(m(2)?s)) or stressful (nitrogen-lacking media at 350 ?mol PAR photons/(m(2)?s)) conditions. The reliable measurement of the cell suspension absorbance using a spectrophotometer without integrating sphere was achieved by deposition of cells on glass-fiber filters in the chlorophyll content range of 3-13 mg/L. Under stressful conditions, a 30-50% decline in biomass and chlorophyll, retention of carotenoids and a build-up of TFA (15-45 % of dry weight) were recorded. Spectral regions sensitive to widely ranging changes in carotenoid-to-chlorophyll ratio and correlated changes of TFA content were revealed. Employing the tight inter-correlation of stress-induced changes in lipid metabolism and rearrangement of the pigment apparatus, the spectral indices were constructed for non-destructive assessment of carotenoid-to-chlorophyll ratio (range 0.3-0.6; root mean square error (RMSE)?=?0.03; r (2)?=?0.93) as well as TFA content of Nannochloropsis sp. biomass (range 5.0-45%; RMSE?=?3.23 %; r (2)?=?0.89) in the broad band 400-550 nm normalized to that in chlorophyll absorption band (centered at 678 nm). The findings are discussed in the context of real-time monitoring of the TFA accumulation by Nannochloropsis cultures under stressful conditions. PMID:20882331

Solovchenko, Alexei; Khozin-Goldberg, Inna; Recht, Lee; Boussiba, Sammy

2010-09-30

118

Improvement of non-destructive fissile mass assays in ? low-level waste drums: A matrix correction method based on neutron capture gamma-rays and a neutron generator  

NASA Astrophysics Data System (ADS)

Within the framework of radioactive waste control, non-destructive assay (NDA) methods may be employed. The active neutron interrogation (ANI) method is now well-known and effective in quantifying low ?-activity fissile masses (mainly 235U, 239Pu, 241Pu) with low densities, i.e. less than about 0.4, in radioactive waste drums of volumes up to 200 l. The PROMpt Epithermal and THErmal interrogation Experiment (PROMETHEE [F. Jallu, A. Mariani, C. Passard, A.-C. Raoux, H. Toubon, Alpha low level waste control: improvement of the PROMETHEE 6 assay system performances. Nucl. Technol. 153 (January) (2006); C. Passard, A. Mariani, F. Jallu, J. Romeyer-Dherber, H. Recroix, M. Rodriguez, J. Loridon, C. Denis, PROMETHEE: an alpha low level waste assay system using passive and active neutron measurement methods. Nucl. Technol. 140 (December) (2002) 303 314]) based on ANI has been under development since 1996 to reach the incinerating ? low level waste (LLW) criterion of about 50 Bq[?] per gram of crude waste (?50 ?g Pu) in 118 l drums on the date the drums are conditioned. Difficulties arise when dealing with matrices containing neutron energy moderators such as H and neutron absorbents such as Cl. These components may have a great influence on the fissile mass deduced from the neutron signal measured by ANI. For example, the calibration coefficient measured in a 118 l drum containing a cellulose matrix (density d = 0.144 g cm-3) may be 50 times higher than that obtained in a poly-vinyl-chloride matrix (d = 0.253 g cm-3). Without any information on the matrix, the fissile mass is often overestimated due to safety procedures and by considering the most disadvantageous calibration coefficient corresponding to the most absorbing and moderating calibration matrix. The work discussed in this paper was performed at the CEA Nuclear Measurement Laboratory in France. It concerns the development of a matrix effect correction method, which consists in identifying and quantifying the matrix components by using prompt gamma-rays following neutron capture. The method aims to refine the value of the adequate calibration coefficient used for ANI analysis. This paper presents the final results obtained for 118 l waste drums with low ?-activity and low density. This paper discusses the experimental and modelling studies and describes the development of correction abacuses based on gamma-ray spectrometry signals.

Jallu, F.; Loche, F.

2008-08-01

119

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

120

Detection limits of a laboratory pulsed gamma neutron activation analysis system for the nondestructive assay of mercury, cadmium, and lead  

Microsoft Academic Search

Detection of Hg, Cd, and Pb within concrete matrices located in 8-gal drums was successfully demonstrated using a pulsed gamma neutron activation analysis system. Real-time assays of 600 s led to the detection of these metals at concentration levels ranging, in parts per million (ppm) by weight, from 487 to 19,820 for Hg, 485 to 8181 for Cd, and 9927

A. R. Dulloo; F. H. Ruddy; T. V. Congedo; J. G. Seidel; R. J. Gehrke

1998-01-01

121

Development of Passive Hemagglutination Assays and Large Animal Antisera for Detection of Hepatitis Associated Antigens.  

National Technical Information Service (NTIS)

Procedures are described and evaluated for large scale purification of hepatitis associated antigen. Purified antigen preparations have been successfully employed for hemagglutination and hemagglutination inhibition assays, and this methodology has been i...

A. M. Prince

1971-01-01

122

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

123

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

SciTech Connect

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

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

2009-01-01

124

Comparison of a Commercial Reversed Passive Latex Agglutination Assay to an Enzyme Immunoassay for the Detection of Shiga Toxin-Producing Escherichia coli  

Microsoft Academic Search

A multicenter study was performed to compare the performance of a prototypic reversed passive latex agglutination assay (VTEC Screen “Seiken”; Denka-Seiken, Japan) with the Premier EHEC Enzyme Immunoassay (Meridian Diagnostics, USA) for the detection of Shiga toxin in 554 diarrheal stool samples. Standard culture on sorbitol MacConkey agar and the use of latex agglutination reagents were included to identify the

K. C. Carroll; K. Adamson; K. Korgenski; A. Croft; R. Hankemeier; J. Daly; C. H. Park

2003-01-01

125

Nondestructive evaluation  

Microsoft Academic Search

Nondestructive evaluation (NDE) is to materials what CAT (computerized axial tomography) scanning is to the human body-an attempt to look inside without opening it up. As in CAT scanning, modern NDE requires sophisticated mathematical software to perform its function. This is especially true with regard to quantitative NDE, wherein we attempt to quantify defects, that is, determine their size, location,

H. A. Sabbagh

1994-01-01

126

Assay of low-level plutonium effluents  

SciTech Connect

In the plutonium recovery section at the Los Alamos National Laboratory, an effluent solution is generated that contains low plutonium concentration and relatively high americium concentration. Nondestructive assay of this solution is demonstrated by measuring the passive L x-rays following alpha decay. Preliminary results indicate that an average deviation of 30% between L x-ray and alpha counting can be achieved for plutonium concentrations above 10 mg/L and Am/Pu ratios of up to 3; for plutonium concentrations less than 10 mg/L, the average deviation is 40%. The sensitivity of the L x-ray assay is approx. 1 mg Pu/L.

Hsue, S.T.; Hsue, F.; Bowersox, D.F.

1981-01-01

127

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

Microsoft Academic Search

The passivated ion implanted planar silicon (IIPS) detector is, in comparison to other semiconductor charged particle detectors such as the silicon surface barrier (SSB) detector, characterised by a thin entrance window and by low leakage current and hence low electronic noise. For the detection of low energy electrons (<~ 200 keV) it has, therefore, the potential of superior sensitivity and

Jonathan Robert Batten

1989-01-01

128

NON-DESTRUCTIVE BEAM MEASUREMENTS.  

SciTech Connect

In high energy accelerators, especially storage rings, non-destructive beam measurements are highly desirable to minimize the impact on the beam quality. In principle, the non-destructive tools can be either passive detectors like Schottky, or active devices which excite either longitudinal or transverse beam motions for the corresponding measurements. An example of such a device is an ac dipole, a magnet with oscillating field, which can be used to achieve large coherent betatron oscillations. It has been demonstrated in the Brookhaven AGS that by adiabatically exciting the beam, the beam emittance growth due to the filamentation in the phase space can be avoided. This paper overviews both techniques in general. In particular, this paper also presents the beam tune measurement with a Schottky detector, phase advance measurements as well as nonlinear resonance measurements with the ac dipoles in the Brookhaven RHIC.

BAI,M.

2004-07-05

129

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

NASA Astrophysics Data System (ADS)

The passivated ion implanted planar silicon (IIPS) detector is, in comparison to other semiconductor charged particle detectors such as the silicon surface barrier (SSB) detector, characterised by a thin entrance window and by low leakage current and hence low electronic noise. For the detection of low energy electrons (<~ 200 keV) it has, therefore, the potential of superior sensitivity and energy resolution. Measurements have been made at room temperature with an IIPS and a SSB detector of similar specifications of the continuous ?- spectra from a 14C source (maximum energy: 156 keV) and of the line spectra from the conversion electrons of a 99mTc source. The sensitivity of a thin window (1.5-2.0 mg cm-2 mica) Geiger to 14C was also investigated. The leakage current, rms noise and capacitance characteristics as a function of the reverse bias voltage were studied for both semiconductor detectors. The IIPS had a sensitivity to 14C ?- detection 26% higher than the SSB and the IIPS with an added light-tight cover had a sensitivity essentially similar to the Geiger. For 119.5 keV conversion electrons, the IIPS had a FWHM of 10.6 keV whereas that for the SSB was 15.0 keV. The rms noise, capacitance and, in particular, leakage current values were lower for the IIPS. Present address and address for correspondence: Electronics, Physics and Electrical Engineering Unit, School of Engineering, Oxford Polytechnic, Oxford OX3 0BP, UK.

Batten, Jonathan Robert

1989-05-01

130

Characterization of waste drums using nonintrusive active and passive computed tomography  

SciTech Connect

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

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

1994-08-01

131

Electromagnetic Nondestructive Evaluation (III)  

Microsoft Academic Search

Within the context of non-destructive testing, the classical `Formulate-Solve-Interpret' model of problem solving becomes `Measure-Recover-Interpret'. But, before one can perform measurements, there must be appropriate instrumentation. In this book on electromagnetic non-destructive evaluation (ENDE) all these aspects (instrumentation, measurement, recovery and interpretation) are treated, though the major emphasis is on the recovery and interpretation aspects. The focus of the book,

R S Anderssen

2000-01-01

132

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

133

Non-Destructive Testing: Ultrasonics.  

National Technical Information Service (NTIS)

This bibliography is a compilation of references on Non-Destructive Testing: Ultrasonics in a series of bibliographies on Non-Destructive Testing. Citations were selected from entries processed into the Defense Documentation Center's data bank during the ...

1971-01-01

134

Passive Sonar  

NASA Astrophysics Data System (ADS)

Passive sonar is a method for detecting acoustic signals in an underwater environment, usually the ocean. The difference between passive and active sonar is that a passive sonar system emits no signals; instead, its purpose is to detect the acoustic signals emanating from external sources. From an historical perspective, the main impetus for the research and development of passive sonar has been its military applications, in particular, the acoustic detection of submarines.

Maranda, Brian H.

135

Passive Radar.  

National Technical Information Service (NTIS)

The basic ideas and concepts of one of the newest branches of radar, that of passive radar, are discussed. A great deal of attention is devoted to questions of the use of passive radar by the armed forces. The physical fundamentals of passive radar, and t...

A. G. Nikolaev S. V. Pertsov

1975-01-01

136

Nondestructive testing techniques  

NASA Astrophysics Data System (ADS)

A comprehensive reference covering a broad range of techniques in nondestructive testing is presented. Based on years of extensive research and application at NASA and other government research facilities, the book provides practical guidelines for selecting the appropriate testing methods and equipment. Topics discussed include visual inspection, penetrant and chemical testing, nuclear radiation, sonic and ultrasonic, thermal and microwave, magnetic and electromagnetic techniques, and training and human factors. (No individual items are abstracted in this volume)

Bray, Don E.; McBride, Don

137

Nondestructive material characterization  

DOEpatents

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

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

1991-01-01

138

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

139

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

140

Passive Radar.  

National Technical Information Service (NTIS)

This book sets forth in brief the physical principles of passive radar, describes the functional diagrams and circuit peculiarities of the apparatus, and offers recommendations for modifying radar receivers to adapt them for receiving natural radio-freque...

A. G. Nikolaev S. V. Pertsov

1975-01-01

141

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

142

Microcomputers and Nondestructive Test Systems.  

National Technical Information Service (NTIS)

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 Di...

R. D. Strong

1983-01-01

143

/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

144

Passive curvaton  

NASA Astrophysics Data System (ADS)

We propose a class of curvaton models which we call passive curvaton. In this Letter, two kinds of passive curvaton are considered. The first one is a pseudoscalar curvaton coupling to a gauge field. Different from the inflaton case, the constraint from formation of primordial black holes (PBHs) is much weaker and large non-Gaussianity (of the equiliteral type) can be produced. The second model is a dilaton-like scalar curvaton coupling to a gauge field. We investigate the scale dependence of non-Gaussianity in this model. In both models, the spectrum and non-Gaussianity are enhanced by the slow-roll parameter of the curvaton field. Other possible passive curvaton models are also mentioned.

Lin, Chia-Min

2013-07-01

145

Nondestructive testing: Neutron radiography and neutron activation. (Latest citations from the INSPEC database). Published Search  

SciTech Connect

The bibliography contains citations concerning the technology of neutron radiography and neutron activation for nondestructive testing of materials. The development and evaluation of neutron activation analysis and neutron diffraction examination of liquids and solids are presented. Citations also discuss nondestructive assay, verification, evaluation, and multielement analysis of biomedical, environmental, industrial, and geological materials. Nondestructive identification of chemical agents, explosives, weapons, and drugs in sealed containers are explored. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

NONE

1996-04-01

146

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

147

Non-destructive interrogation of uranium using PGAA  

Microsoft Academic Search

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

G. L Molnár; Zs. Révay; T. Belgya

2004-01-01

148

Neutron Scanning System for Nondestructive Testing.  

National Technical Information Service (NTIS)

Presented are the methods of nondestructive testing, based on neutron passing, outlet from the reactor, through the samples. Considered are possibilities of the neutron-spectrometric method of nondestructive sample analysis. Given is a description of half...

K. D. Zhuravlev V. M. Ivanov L. V. Karin N. I. Kroshkin V. I. Nazarenko

1980-01-01

149

Delayed gamma technique for fissile material assay  

Microsoft Academic Search

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

Vladimir Mozin; Stephen Tobin; Jasmina Vujie; Alan Hunt

2010-01-01

150

Reflection shearography for nondestructive evaluation  

Microsoft Academic Search

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.

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

2004-01-01

151

Bridge Management and Nondestructive Evaluation  

Microsoft Academic Search

The City and County of Denver (CCD) Public Works Department owns, inspects, and maintains 531 bridges in its inventory of which 264 are considered major structures spanning over 6.1 m in length. In this paper, a methodology using the CCD major bridge network for the application of nondestructive evaluation (NDE) methods in bridge inspections is explained. The methodology, called Bridge

Kevin L. Rens; Carnot L. Nogueira; David J. Transue

2005-01-01

152

Assay for Lipolytic and Proteolytic Activity Using Marine Substrates.  

National Technical Information Service (NTIS)

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

R. A. Tom E. V. Crisan

1974-01-01

153

A non-destructive characterization and real time monitor technique for low-loss, polymeric waveguide circuits  

Microsoft Academic Search

Optical polymer waveguide is a key passive component for the optical interconnection. Design, fabrication, and characterization of high performance waveguides have critical importance for the success of optoelectronic integration. In addition, defect effect, coupling, leakages and cross talk etc. are big concerns for the lightwave circuits. We present here a fast, non-destructive, sensitive, and real-time technique for detailed investigation of

Fengtao Wang; Fuhan Liu; Gee-Kung Chang; Mathew Q. Yao; Ali Adibi; Rao Tummala

2008-01-01

154

Lumped Network Passivity Criteria.  

National Technical Information Service (NTIS)

The classical time-energy definition of passivity is employed to generate workable passivity criteria for lumped networks which are characterizable by standard form state equations. In general, the demonstration of passivity entails the construction of a ...

R. A. Rohrer

1967-01-01

155

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

156

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

157

Ultrasonic piezotransducers for nondestructive testing  

NASA Astrophysics Data System (ADS)

The principal types of piezoelectric transducers, their characteristics, and applications to nondestructive ultrasonic testing are examined. In particular, attention is given to ultrasonic transducers with a plane-parallel piezoelectric plate vibrating in the thickness direction, multilayer transducers, variable-thickness wideband transducers, nonresonantly excited piezoelectric transducers, and resonance transducers excited by an inhomogeneous electric field. The discussion also covers the acoustic fields of piezoelectric transducers, the design and fabrication of piezotransducers, and measurement of the characteristics of piezotransducers.

Ermolov, Igor'nikolaevich; Gitis, Mikhail Borisovich; Korolev, Mikhail Viktorovich; Karpel'Son, Arkadii Efimovich; Mel'Kanovich, Anatolii Fedorovich

158

Nondestructive assay holdup measurements with the Ortec detective  

SciTech Connect

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

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

2009-01-01

159

An expert system framework for nondestructive waste assay  

SciTech Connect

Management and disposition of transuranic (RU) waste forms necessitates determining entrained RU and associated radioactive material quantities as per National RU Waste Characterization Program requirements. Technical justification and demonstration of a given NDA method used to determine RU mass and uncertainty in accordance with program quality assurance is difficult for many waste forms. Difficulties are typically founded in waste NDA methods that employ standards compensation and/or employment of simplifying assumptions on waste form configurations. Capability to determine and justify RU mass and mass uncertainty can be enhanced through integration of waste container data/information using expert system and empirical data-driven techniques with conventional data acquisition and analysis. Presented is a preliminary expert system framework that integrates the waste form data base, alogrithmic techniques, statistical analyses, expert domain knowledge bases, and empirical artificial intelligence modules into a cohesive system. The framework design and bases in addition to module development activities are discussed.

Becker, G.K.

1996-10-01

160

Application of nondestructive gamma-ray and neutron techniques for the safeguarding of irradiated fuel materials  

SciTech Connect

Nondestructive gamma-ray and neutron techniques were used to characterize the irradiation exposures of irradiated fuel assemblies. Techniques for the rapid measurement of the axial-activity profiles of fuel assemblies have been developed using ion chambers and Be(..gamma..,n) detectors. Detailed measurements using high-resolution gamma-ray spectrometry and passive neutron techniques were correlated with operator-declared values of cooling times and burnup.

Phillips, J.R.; Halbig, J.K.; Lee, D.M.; Beach, S.E.; Bement, T.R.; Dermendjiev, E.; Hatcher, C.R.; Kaieda, K.; Medina, E.G.

1980-05-01

161

Simulation and Visualisation for Electromagnetic Nondestructive Evaluation  

Microsoft Academic Search

This paper reviews the state-of-the art of modelling, simulation and visualisation and reviews the recent development of modelling, simulation and visualisation software for Nondestructive Evaluation (NDE). Simulation and visualisation can assist in the design and development of electromagnetic sensing and imaging techniques and systems for nondestructive testing, feature extraction and inverse problems for quantitative nondestructive evaluation. After reviewing the state-of-the

Anthony Simm; Ilham Zainal Abidin; Gui Yun Tian; Wai Lok Woo

2010-01-01

162

Operational and Regulatory Performance of Waste Crate Assay Systems at RFETS  

SciTech Connect

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 Boxes (SWB) and larger Low Level Waste (LLW) containers. To this end, Kaiser Hill, with the support of BNFL Instruments, Inc. (BII) and Los Alamos National Laboratory (LANL), has recently deployed two new crate assay systems. These systems provide the capacity to meet the assay requirements associated with the Deactivation and Decommissioning (D&D) at RFETS. The Super High Efficiency Neutron Coincidence Counting System (SuperHENC) was designed and fabricated as a collaborative effort between RFETS, LANL and BII. The purpose of this counter is to provide a WIPP certified assay capability for SWBs with a sensitivity that allows for TRU/LLW sorting. The SuperHENC has been in operation since early 2001. The BII Multi-Purpose Crate Counter (MPCC) is based on the Imaging Passive Active Neutron (IPAN) technology. This counter was designed to provide diverse capacity for WIPP certified assay of SWBs and to provide assay capability for larger LLW crates that are generated at RFETS. The MPCC has been in operation since early 2002. In order to meet the requirement for measurement of the WIPP tracked radionuclides, both systems incorporate a BII Gamma Energy Analysis sub-system. The unique Energy Times Attenuation (ETA) method is used to provide isotopic mass fractions for diverse waste streams. These systems were the first, and at this time the only, waste crate assay systems that have achieved WIPP certification. This represents a significant achievement given that the performance criteria applied to the measurements of large crates is identical to the criteria for 55-gallon (208 liter) drums. They are now both fully operational at RFETS and continue to successfully support the site closure mission.

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

2003-02-27

163

Operational and regulatory performance of waste crate assay systems at RFETS.  

SciTech Connect

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 Boxes (SWB) and larger Low Level Waste (LLW) containers. To this end, Kaiser Hill, with the support of BNFL Instruments, Inc . (BIn) and Los Alamos National Laboratory (LANL), has recently deployed two new crate assay systems . These systems provide the capacity to meet the assay requirements associated with the Deactivation and Decommissioning (D&D) at RFETS . The Super High Efficiency Neutron Coincidence Counting System (SuperHENC) was designed and fabricated as a collaborative effort between RFETS, LANL and BII. The purpose of this counter is to provide a WIPP certified assay capability for SWBs with a sensitivity that allows for TRU/LLW sorting. The SuperHENC has been in operation since early 2001 . The BII Mu1ti-Purpose Crate Counter (MPCC) is based on the Imaging Passive Active Neutron (IPANTM) technology. This counter was designed to provide diverse capacity for WIPP certified assay of SWBs and to provide assay capability for larger LLW crates that are generated at RFETS. The MPCC h as been in operation since early 2002 . In order to meet the requirement for measurement of the WIPP tracked radionuclides, both systems incorporate a BII Gamma Energy Analysis sub-system . The unique Energy Times . Attenuation (ETA) method is used to provide isotopic mass fractions for diverse wastes treams: These systems were the first, and at this time the only, waste crate assay systems that have achieved WIPP certification. This represents a significant achievement given that the performance criteria applied to the measurements of large crates is identical to the criteria for 55-gallon (208 liter) drums . They are now both fully operational at RFETS and continue to successfully support the site closure mission .

Clapham, M. (Martin); Franco, J. B. (Johnna B.); Simpson, A.; Santo, J.; Menlove, Howard O.; Durel, F. M.

2003-01-01

164

46 CFR 151.04-7 - Nondestructive testing.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Nondestructive testing. 151.04-7 Section 151.04-7...and Certification § 151.04-7 Nondestructive testing. (a) Before nondestructive testing may be conducted to meet §...

2011-10-01

165

46 CFR 151.04-7 - Nondestructive testing.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Nondestructive testing. 151.04-7 Section 151.04-7...and Certification § 151.04-7 Nondestructive testing. (a) Before nondestructive testing may be conducted to meet §...

2012-10-01

166

46 CFR 151.04-7 - Nondestructive testing.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Nondestructive testing. 151.04-7 Section 151.04-7...and Certification § 151.04-7 Nondestructive testing. (a) Before nondestructive testing may be conducted to meet §...

2010-10-01

167

46 CFR 151.04-7 - Nondestructive testing.  

Code of Federal Regulations, 2010 CFR

...2009-10-01 2009-10-01 false Nondestructive testing. 151.04-7 Section 151.04-7...and Certification § 151.04-7 Nondestructive testing. (a) Before nondestructive testing may be conducted to meet §...

2009-10-01

168

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

169

Passive and Active Magnetic Sensing to Characterize Corrosion of Metals  

NASA Astrophysics Data System (ADS)

Corrosion is a serious and costly problem for the world's infrastructure. Traditional non-destructive methods have proven to be useful in determining extent and rate of corrosion; however they are limited by the need to electrically connect to the inspected metal. Magnetic sensing is proposed as a way to overcome these limitations. Preliminary results are presented here on the use of GMR magnetic field sensors to passively and actively detect corrosion of aluminum and steel plates. Passive sensing seems particularly useful to identify localized active corrosion on aluminum, while active sensing appears useful to identify active corrosion in steel.

Gallo, G. E.; Popovics, J. S.; Chapman, P. L.

2009-03-01

170

Nondestructive evaluation of oriented strand board exposed to ...  

Treesearch

Description: Stress wave nondestructive evaluation (NDE) technologies are being ... in our laboratory to evaluate the performance properties of engineered wood. ... examined the relationship between nondestructive stress wave transmission, ...

171

Actively modulated acoustic nondestructive evaluation of concrete  

Microsoft Academic Search

The need in testing concrete is not only the ability to detect large cracks or flaws but also reliably and efficiently to quantify the residual strength. Current nondestructive testing methods are capable only of discriminating high states of damage. This study lays the foundation for an evaluation method that may be significantly more sensitive than traditional nondestructive evaluation (NDE) to

Kraig Warnemuende; Hwai-Chung Wu

2004-01-01

172

Nondestructive Evaluation Program. Progress in 1985  

Microsoft Academic Search

The increasing cost of equipment for power generating plants and the potential increases in productivity and safety available through rapidly developing Nondestructive Evaluation (NDE) technology led EPRI to initiate a Nondestructive Evaluation Program in 1974. To date, the major focus has been on light water reactor inspection problems; however, increased application to other systems is now under way. This report

G. J. Dau; M. M. Behravesh; S. N. Liu; T. Oldberg; M. J. Jr. Avioli; J. R. Scheibel; D. Sharma; D. M. Norris; S. W. Jr. Tagart; T. J. Griesbach

1986-01-01

173

Pulse compression approach to infrared nondestructive characterization  

Microsoft Academic Search

Infrared thermography is a whole field, noncontact, and nondestructive characterization technique widely used for the investigation of subsurface features in various solid materials (conductors, semiconductors, and composites). Increased demand for greater subsurface probing in thermal nondestructive testing is often thwarted by the probing high peak power into the sample, for which narrow pulse operation is usually used. The technique of

Ravibabu Mulaveesala; Jyani Somayajulu Vaddi; Pushpraj Singh

2008-01-01

174

Nondestructive evaluation of compacted clayey soils  

Microsoft Academic Search

Compacted clayey soils are analyzed using nondestructive testing methods. Ultrasonic testing and image analysis are used as nondestructive testing techniques. Tests were conducted on three clayey soils with low to high plasticities. The soils are compacted and then allowed to dry or subjected to wetting and drying cycles subsequent to compaction. Ultrasonic tests are performed to determine small strain elastic

Gokhan Inci

2001-01-01

175

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

176

Simulation of Rate-Related (Dead-Time) Losses In Passive Neutron Multiplicity Counting Systems  

SciTech Connect

Passive Neutron Multiplicity Counting (PNMC) based on Multiplicity Shift Register (MSR) electronics (a form of time correlation analysis) is a widely used non-destructive assay technique for quantifying spontaneously fissile materials such as Pu. At high event rates, dead-time losses perturb the count rates with the Singles, Doubles and Triples being increasingly affected. Without correction these perturbations are a major source of inaccuracy in the measured count rates and assay values derived from them. This paper presents the simulation of dead-time losses and investigates the effect of applying different dead-time models on the observed MSR data. Monte Carlo methods have been used to simulate neutron pulse trains for a variety of source intensities and with ideal detection geometry, providing an event by event record of the time distribution of neutron captures within the detection system. The action of the MSR electronics was modelled in software to analyse these pulse trains. Stored pulse trains were perturbed in software to apply the effects of dead-time according to the chosen physical process; for example, the ideal paralysable (extending) and non-paralysable models with an arbitrary dead-time parameter. Results of the simulations demonstrate the change in the observed MSR data when the system dead-time parameter is varied. In addition, the paralysable and non-paralysable models of deadtime are compared. These results form part of a larger study to evaluate existing dead-time corrections and to extend their application to correlated sources. (authors)

Evans, L.G.; Norman, P.I.; Leadbeater, T.W. [School of Physics and Astronomy, University of Birmingham, Edgbaston, Birmingham (United Kingdom); Croft, S.; Philips, S. [Canberra Industries Inc., Meriden, CT (United States)

2008-07-01

177

The Nuclear Renaissance - Implications on Quantitative Nondestructive Evaluations  

SciTech Connect

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

Matzie, Regis A. [Westinghouse Electric Company, 20 International Drive, Windsor, CT 06095 (United States)

2007-03-21

178

Nondestructive Imaging of Individual Biomolecules  

NASA Astrophysics Data System (ADS)

Radiation damage is considered to be the major problem that still prevents imaging an individual biological molecule for structural analysis. So far, all known mapping techniques using sufficient short wavelength radiation, be it x rays or high energy electrons, circumvent this problem by averaging over many molecules. Averaging, however, leaves conformational details uncovered. Even the anticipated use of ultrashort but extremely bright x-ray bursts of a free electron laser shall afford averaging over 106 molecules to arrive at atomic resolution. Here, we present direct experimental evidence for nondestructive imaging of individual DNA molecules. In fact, we show that DNA withstands coherent low energy electron radiation with deBroglie wavelength in the Ångstrom regime despite a vast dose of 108electrons/nm2 accumulated over more than one hour.

Germann, Matthias; Latychevskaia, Tatiana; Escher, Conrad; Fink, Hans-Werner

2010-03-01

179

Nondestructive Imaging of Individual Biomolecules  

SciTech Connect

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

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

2010-03-05

180

Non-Destructive Testing Scanner  

NASA Astrophysics Data System (ADS)

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

181

Passive Building Control System.  

National Technical Information Service (NTIS)

The design is called Passive Building Predictive Control System. It consists of one central controller and a set of local understations, one in each working space (office room). It can manage passive solar gain, natural ventilation, heating and lighting i...

S. H. Liem P. J. Lute A. H. C. van Paassen M. Verwaal

1989-01-01

182

Nondestructive Greenberger-Horne-Zeilinger-state analyzer  

NASA Astrophysics Data System (ADS)

We propose a method to construct a nondestructive n-qubit Greenberger- Horne-Zeilinger (GHZ)-state analyzer. The method is applied to any systems in which two-qubit parity gates, controlled-phase gates, or controlled-NOT gates can be realized. We also present a simplified two-photon parity gate with which a nondestructive n-photon GHZ-state analyzer could be largely simplified. The nondestructive GHZ-state analyzer is expected to find useful applications for economical quantum-information processing.

Wang, Xin-Wen; Zhang, Deng-Yu; Tang, Shi-Qing; Xie, Li-Jun

2013-02-01

183

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

184

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...

185

[Fundamental studies of passivity and passivity breakdown  

SciTech Connect

We developed and experimentally tested physical models for growth and breakdown of passive films on metal surfaces. These models are ``point defect models,`` in which the growth and breakdown are described in terms of movement of anion and cation vacancies. The work during the past 5 years resulted in: theory of growth and breakdown of passive films, theory of corrosion-resistant alloys, electronic structure of passive films, and estimation of damage functions for energy systems. Proposals are give for the five ongoing tasks. 10 figs.

Macdonald, D.D.

1993-07-01

186

Nonlinear acoustic nondestructive testing for concrete durability  

Microsoft Academic Search

Several nondestructive testing methods can be used to determine the damage in a concrete structure. Linear ultrasonic techniques, e.g. pulse-velocity and amplitude attenuation, are very common in nondestructive evaluation. Velocity of propagation is not very sensitive to the degrees of damage unless a great deal of micro-damage having evolving into localized macro-damage. This transition typically takes place around 80% of

Hwai-Chung Wu; Kraig Warnemuende

2000-01-01

187

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

SciTech Connect

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

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

2012-06-01

188

Nondestructive testing for identifying poor-quality onions  

NASA Astrophysics Data System (ADS)

Methods of nondestructively examining Granex type sweet onions are needed to insure that only good quality onions are shipped at harvest and to avoid putting infected onions in controlled atmosphere (CA) storage where they occupy valuable space and can ruin surrounding onions. A Toshiba TCT 20Ax tomographic scanner operated in the line scan mode and an incandescent light box were used to evaluate the potential for detecting infected onions nondestructively. A study (CA storage study) involving 200 onions, 100 harvested early and 100 harvested late, one half destructively inspected before the remaining half were placed into CA storage was initiated May 1994. All onions were line scanned and scored with the light box before CA storage and those in CA storage were line (will be) scanned and optical scored on retrieval from the storage. An additional study (Disease storage study) involving 40 onions, late harvest, stored at 25C, 60% rh for three weeks with line scanning as above on a weekly interval. After the third week these fruit were assayed for visual damage and for decay organisms. Results from the incandescent light box scoring were not encouraging. From both studies the number of defects, average defect size and the difference image intensity as determined from line scanning were the major contributing parameters to a discriminant analyses model predicting about 70% or better accuracy.

Tollner, Ernest W.; Hung, Y.-C.; Maw, B. W.; Sumner, D. R.; Gitaitis, R. D.

1995-01-01

189

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

190

Nondestructive Characterization of Aged Components  

SciTech Connect

It is known that high energy radiation can have numerous effects on materials. In metals and alloys, the effects include, but may not be limited to, mechanical property changes, physical property changes, compositional changes, phase changes, and dimensional changes. Metals and alloys which undergo high energy self-irradiation are also susceptible to these changes. One of the greatest concerns with irradiation of materials is the phenomenon of void swelling which has been observed in a wide variety of metals and alloys. Irradiation causes the formation of a high concentration point defects and microclusters of vacancies and interstitials. With the assistance of an inert atom such as helium, the vacancy-type defects can coalesce to form a stable bubble. This bubble will continue to grow through the net absorption of more vacancy-type defects and helium atoms, and upon reaching a certain critical size, the bubble will begin to grow at an accelerated rate without the assistance of inert atom absorption. The bubble is then said to be an unstably growing void. Depending on the alloy system and environment, swelling values can reach in excess of 50% !V/Vo where Vo is the initial volume of the material. Along with dimensional changes resulting from the formation of bubbles and voids comes changes in the macroscopically observed speed of sound, moduli, electrical resistivity, yield strength, and other properties. These effects can be detrimental to the designed operation of the aged components. In situations where irradiation has sufficient time to cause degradation to materials used in critical applications such as nuclear reactor core structural materials, it is advisable to regularly survey the material properties. It is common practice to use surveillance specimens, but this is not always possible. When surveillance materials are not available, other means for surveying the material properties must be utilized. Sometimes it is possible to core out a small sample which may be used for material properties measurements. A more appealing solution is to use nondestructive evaluation (NDE) methods.

Panetta, Paul D.; Toloczko, Mychailo B.; Garner, Francis A.; Balachov, Iouri I.

2003-10-21

191

An Innovative Non-Destructive and Computational Method for Uranium Activity and Enrichment Verification of UF Cylinder  

Microsoft Academic Search

Verification of ²³U enrichment in uranium hexafluoride (UF) cylinders is often achieved by destructive and non-destructive assay techniques. These techniques are time consuming, need suitable and similar standard, in addition to loss of the nuclear material in the case of destructive analysis. This paper introduce an innovative approach for verifying of ²³U enrichment in UF cylinder. The approach is based

Sayed A. El-Mongy; K. M. Allam; Osama M. Farid

2006-01-01

192

Optimizing active and passive calibration of optical tweezers  

NASA Astrophysics Data System (ADS)

To obtain quantitative information from optical trapping experiments it is essential to perform a precise force calibration. Therefore, sources of noise should be pinpointed and eliminated. Fourier analysis is routinely used to calibrate optical trapping assays because it is excellent for pinpointing high frequency noise. In addition, Allan variance analysis is particularly useful for quantifying low frequency noise and for predicting the optimal measurement time. We show how to use Allan variance in combination with Fourier analysis for optimal calibration and noise reduction in optical trapping assays. The methods are applied to passive assays, utilizing the thermal motion of a trapped particle, and to active assays where the bead is harmonically driven. The active method must be applied in assays where, for example, the viscoelastic properties of the medium or the size or shape of the trapped object are unknown. For measurement times shorter than the optimal calibration time the noise is larger in active than in the passive assays. For times equal to or longer than the optimal measurement time, though, the noise on passive and active assays is identical. As an example, we show how to quantify the influence on measurement noise of bead size and chamber geometry in active and passive assays.

Andersson, M.; Czerwinski, F.; Oddershede, L. B.

2011-04-01

193

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

194

Passive solar underground home  

Microsoft Academic Search

A 2700 ft² passive solar, underground house is described. Dirt from a near-by swamp was used to berm the structure; 2 to 3 feet of dirt are piled on the roof. Glazing on the south side (200 ft²) provides passive solar heat as well as daylighting. The open design is described and illustrated. (MJJ)

Pauls

1978-01-01

195

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

196

Electrode Passivation Studies.  

National Technical Information Service (NTIS)

Studies of the passivation of Zn-Fe, Zn-Mn, Zn-Co, and Zn-Ni alloys were made potentiostatically. Alloys of 90 Zn 10 Fe corrode at a high rate even when passive. Alloys of 83Zn-17 Mn have low, active dissolution currents. The 89 Zn - 11 Co alloys have hig...

S. B. Brummer A. C. Makrides J. Bradspies

1966-01-01

197

Teaching the Passive  

ERIC Educational Resources Information Center

|A discussion of teaching the passive voice in second language programs considers underlying attitudes toward grammar and grammar teaching. It is noted that Business German textbooks do not incorporate notions of the thought-to-grammar-pattern relationship, even though the passive voice appears twice as often in technical as in nontechnical…

Rockwood, Heidi

198

Passive walking with knees  

Microsoft Academic Search

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

T. McGeer

1990-01-01

199

Overcoming Passive Behavior.  

ERIC Educational Resources Information Center

|Passivity in learning disabled children is identified as either inborn or as "learned helplessness," and the role of the teacher in overcoming passivity is noted. Teachers can help students understand themselves, become active agents in learning, and use self monitoring devices. (CL)|

Kay, Marilyn

1986-01-01

200

Passive dispersal in arachnids  

Microsoft Academic Search

Some arachnids (spiders, mites and pseudoscorpions) are able to use both active and passive dispersal. The best-known passive dispersal method in arachnids is called ëballooningí and starts with ëtiptoe behaviourí. Using threads of silk, spiders can move from place to place with air currents. Usually the spider aeronauts are small, but sometimes larger ones can also be transported in this

DARIA BAJERLEIN

2007-01-01

201

Passive solar rowhouses  

SciTech Connect

This article discusses an urban renovation project in north Philadelphia using passive solar rowhouses to help revitalize the community. The topics covered include energy efficient building features; passive solar features; energy performance; costs; and improving performance designs. Project details are given.

Thayer, B.M.

1995-07-01

202

Electrode Passivation Studies.  

National Technical Information Service (NTIS)

The operation of primary, reserve batteries in a passive mode was explored. An anode can be put into the passive state by an appropriate electrical pulse and can be maintained in this condition by suitable connection to the positive battery electrode. Act...

S. B. Brummer A. C. Makrides A. J. Bradspies

1967-01-01

203

Non-destructive measurement technologies for nuclear safeguards  

SciTech Connect

There are three aspects that need to be in place in order to maintain a valid safeguards system: (1) Physical protection; guarding the access to nuclear materials using physical protection and surveillance. (2) Accounting systems; computer based accounting systems that provide the current location of nuclear materials, quantities, and the uncertainty in the assayed values. (3) Measurement systems; detectors, data acquisition systems and data analysis methods that provide accurate assays of nuclear material quantities for the accounting system. The authors expand on this third aspect, measurement systems, by discussing nondestructive assay (NDA) techniques. NDA is defined as the quantitative or qualitative determination of the kind and/or amount of nuclear material in an item without alteration or invasion of the item. This is contrasted with destructive analysis which is the process of taking small samples from the item in question, analyzing those samples by chemical analysis, destroying the original nature of the samples in the process (hence the term destructive), and applying the results to the entire item. Over the past 30 years, numerous techniques, using the atomic and nuclear properties of the actinides, have been developed for reliable, rapid, accurate, and tamper-proof NDA of nuclear materials. The authors distinguish between two types of measurements: the first involving the detection of spontaneously emitted radiation, produced by the natural radioactive decay processes; the second involving the detection of induced radiation, produced by irradiating the sample with an external radiation source.

Gavron, A.

1998-04-01

204

46 CFR 98.25-97 - Nondestructive testing.  

Code of Federal Regulations, 2012 CFR

...MISCELLANEOUS VESSELS SPECIAL CONSTRUCTION, ARRANGEMENT, AND OTHER PROVISIONS FOR CERTAIN DANGEROUS CARGOES IN BULK Anhydrous Ammonia in Bulk § 98.25-97 Nondestructive testing. (a) Before nondestructive testing may be conducted to meet §...

2012-10-01

205

Three dimensional ultrasonic imaging: An aging aircraft nondestructive inspection tool.  

National Technical Information Service (NTIS)

Ultrasonic nondestructive evaluation is a valuable technique for finding defects in aircraft structures. It can detect unbonds, corrosion damage and cracks in various aircraft components. Ultrasonic nondestructive evaluation techniques interrogate materia...

G. H. Thomas S. Benson S. Crawford

1993-01-01

206

NONDESTRUCTIVE EVALUATION (NDE) OF DAMAGED STRUCTURAL CERAMICS  

SciTech Connect

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. [US Army Research Laboratory, 4600 Deer Creek Loop, Aberdeen Proving Ground, MD 21005-5066 (United States)

2009-03-03

207

Passive solar heating  

SciTech Connect

Buildings have been designed to use solar gains for winter heating for several millenia, but the quantitative basis for passive solar design has only been developed in the last decade. A simplified lumped-capacitance model is used to provide insight into the physics of passive building behavior. Three passive design methods are described: the Solar Load Ratio (SLR) method based on correlations to simulation results; the Gordon-Zarmi closed-form analytical model; and the unutilizability model of Monsen and Klein. Model predictions are compared with measured results; agreement is good if measured building characteristics are used. Numerous passive houses use less than 2 Btu/ft/sup 2/-DD for auxiliary heating and consensus is developing that modest levels of passive glazing combined with superinsulation techniques can provide the best feature of both approaches. 28 references, 6 figures, 6 tables.

Claridge, D.E.; Mowris, R.J.

1985-01-01

208

Passive solar construction handbook  

SciTech Connect

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

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

1981-08-01

209

Passive solar heating  

NASA Astrophysics Data System (ADS)

Buildings have been designed to use solar gains for winter heating for several millenia, but the quantitative basis for passive solar design has only been developed in the last decade. A simplified lumped capacitance model is used to provide insight into the physics of passive building behavior. Three passive design methods are described: the Solar Load Ratio (SLR) method based on correlations to simulation results; the Gordon/Zarmi closed form analytical mode;; and the ``unutilizability'' model of Monsen and Klein. Model predictions are compared with measured results; agreement is good if measured building characteristics are used. Numerous passive houses use less than 2 Btu/ft2-DD for auxiliary heating and consensus is developing that modest levels of passive glazing combined with superinsulation techniques can provide the best feature of both approaches.

Claridge, David E.; Mowris, Robert J.

1985-11-01

210

Neutron Generators for Spent Fuel Assay  

Microsoft Academic Search

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

Ludewigt; Bernhard A

2010-01-01

211

46 CFR 98.25-97 - Nondestructive testing.  

Code of Federal Regulations, 2010 CFR

...2009-10-01 2009-10-01 false Nondestructive testing. 98.25-97 Section 98.25-97...Anhydrous Ammonia in Bulk § 98.25-97 Nondestructive testing. (a) Before nondestructive testing may be conducted to meet §...

2009-10-01

212

46 CFR 98.25-97 - Nondestructive testing.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Nondestructive testing. 98.25-97 Section 98.25-97...Anhydrous Ammonia in Bulk § 98.25-97 Nondestructive testing. (a) Before nondestructive testing may be conducted to meet §...

2010-10-01

213

Topoisomerase Assays  

PubMed Central

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

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

2012-01-01

214

Nondestructive examination development and demonstration plan  

SciTech Connect

Nondestructive examination (NDE) of waste matrices using penetrating radiation is by nature very subjective. Two candidate systems of examination have been identified for use in WRAP 1. This test plan describes a method for a comparative evaluation of different x-ray examination systems and techniques.

Weber, J.R.

1991-08-21

215

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

216

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

217

Computer modeling of eddy current nondestructive testing  

Microsoft Academic Search

Nondestructive evaluation (NDE) is to materials what CAT scanning is to the human body--an attempt to look inside without opening up the body. As in CAT scanning, modern NDE requires sophisticated mathematical software to perform its function. This is especially true with regard to quantitative NDE, wherein an attempt is made to quantify defects, that is, determine their size, location,

H. A. Sabbagh; J. C. Treece; R. K. Murphy; Lai Wan Woo

1993-01-01

218

Non-destructive testing of divertor components  

Microsoft Academic Search

This task within the EU R&D for ITER had two main objectives: (1) qualification of inspection procedures for plasma facing components (PFC), (2) assessment of the behaviour of calibrated defects under high heat flux (HHF) cyclic loading. The ultimate goal of this work was to demonstrate that the reliable identification of fatal defects by the chosen non-destructive testing (NDT) methods

M Merola; P Chappuis; F Escourbiac; M Grattarola; H Jeskanen; P Kauppinen; L Plöchl; B Schedler; J Schlosser; I Smid; S Tähtinen; R Vesprini; E Visca; A Zabernig

2002-01-01

219

Nondestructive ultrasonic determination of avocado softening process  

Microsoft Academic Search

A testing technique based on a new nondestructive ultrasonic device was applied to a whole avocado fruit to measure its internal changes during ripening and to assess its quality. The method was based on local measurements of ultrasonic wave velocity and attenuation, by means of two inclined ultrasonic probes, which were moved across the fruit peel. Multiple readings of wave

Amos Mizrach; Uri Flitsanov

1999-01-01

220

Nondestructive Evaluation Program: Progress in 1987  

Microsoft Academic Search

The increasing cost of equipment for power generating plants and the potential increases in productivity and safety available through rapidly developing Nondestructive Evaluation (NDE) technology led EPRI to initiate a Nondsetructive Evaluation Program in 1974. To date, the major focus has been on light water reactor inspection problems; however, increased application to other systems is now under way. This report

M. J. Jr. Avioli; G. J. Dau; J. Edmonds; S. Gehl; S. N. Liu; J. Stein; R. Viswanathan; C. S. Welty

1988-01-01

221

Knowledge based systems in nondestructive evaluation  

Microsoft Academic Search

This paper dicusses the application of knowledge based systems technology to problems in nondestructive evaluation (NDE). The Saft Image Interpretation Assistant (SIIA) is used as an illustrative example. SIIA is a prototype knowledge based system designed to assist in making the operation of the Synthetic Aperture Focusing Technique (SAFT) Ultrasonic Inspection System more reliable and efficient. The two primary motivations

Melton

1987-01-01

222

Intube nondestructive testing of main gas pipelines  

Microsoft Academic Search

A complex of auxiliary equipment for in-tube nondestructive testing of main gas pipelines (MGPs) via magnetic flaw detectors\\u000a is described. A list and schedule of procedures for in-tube inspection of MGPs are presented. Typical flaws in the tube metal\\u000a of MGPs are studied and classified by the degree of hazard.

V. A. Kanaikin; V. E. Loskutov; A. F. Matvienko; B. V. Patramanskii

2007-01-01

223

Method for non-destructive testing  

DOEpatents

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

Akers, Douglas W. (Idaho Falls, ID)

2011-08-30

224

High resolution applications in nondestructive testing  

Microsoft Academic Search

Radioscopy and computed tomography in medical applications are well established and have reached a high level of development. Compared to medical applications industrial nondestructive-testing (NDT) has to deal with a large variety of different materials and material combinations, densities and density dynamics, geometries and structures which need to be inspected. This large variation necessitates the use and intelligent combination of

Norman Uhlmann; Frank Nachtrab; Michael Salamon; Susanne Burtzlaff; Theobald Fuchs; Randolf Hanke

2008-01-01

225

Neutron backscattering nondestructive-test instruments  

Microsoft Academic Search

Calculations and measurements are used in recommendations on neutron nondestructive testing and radioisotope automatic devices operating with one-sided access, where emphasis is placed on optimizing the major components for particular industrial purposes. The major working and other characteristics are given for various instruments: thickness gauges, level gauges, and means of detecting blocking points in pipelines.

Pekarskii

1988-01-01

226

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

227

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

228

Passive Infrared Resolution Target.  

National Technical Information Service (NTIS)

This patent describes a passive target array, for measuring the resolution of infrared reconnaissance sets, having a heat retaining background pad. A plurality of perforated aluminum strips are laid on the pad in a conventional photographic resolution tar...

L. O. Vroombout

1977-01-01

229

Assay of heavy water in drums for safeguards purposes  

SciTech Connect

This paper examines several techniques for rapid nondestructive assay of drums of D/sub 2/O. Five methods have been examined: neutron capture in hydrogen, photodisintegration of deuterium, neutron transmission, neutron die-away time measurements, and acoustic velocity measurements.

Fainberg, A.; Zucker, M.S.; Lemley, J.R.; Weinstock, E.V.

1981-01-01

230

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

231

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

232

Nondestructive technique for detecting diseased poultry carcasses  

NASA Astrophysics Data System (ADS)

In response to the need of the U.S. Food Safety and Inspection Service, the Agriculture Research Service has undertaken a project to develop an accurate, reliable, and nondestructive sensor for detecting poultry diseased carcasses on-line at poultry processing plants. This paper presents some results of a study on the development of a nondestructive technique for the detection of abnormal poultry carcasses based on the spectroscopy of the carcasses. A diode array spectrophotometer equipped with a fiber optic probe was used to obtain optical spectra of the breasts of normal, septicemic, and cadaver poultry carcasses in visible and near-infrared regions (500 - 1100 nm). Optimal wavelengths of reflectance and interactance in the range of 500 to 850 nm were obtained for classifying the carcasses into normal and abnormal (septicemic and cadaver) classes. A back-propagation neural network model was used to develop classifiers for the classification of poultry carcasses into normal, septicemic, and cadaver classes.

Chen, Yud-Ren

1993-04-01

233

Pulse compression approach to infrared nondestructive characterization.  

PubMed

Infrared thermography is a whole field, noncontact, and nondestructive characterization technique widely used for the investigation of subsurface features in various solid materials (conductors, semiconductors, and composites). Increased demand for greater subsurface probing in thermal nondestructive testing is often thwarted by the probing high peak power into the sample, for which narrow pulse operation is usually used. The technique of pulse compression offers a means of increasing the average power available to illuminate test specimen without any loss of the depth resolution needed for the tactical requirements. This is accomplished by transmitting a wide pulse in which the incident heat flux is frequency modulated and then, by proper signal processing methods, causing a time compression of the received signal to a much narrower pulse of high effective peak power. For the demonstration, a mild steel sample having flat bottom holes at various depths is introduced and detection capability of the proposed approach has been studied. PMID:19044447

Mulaveesala, Ravibabu; Vaddi, Jyani Somayajulu; Singh, Pushpraj

2008-09-01

234

Cellulase Assays  

NASA Astrophysics Data System (ADS)

Cellulose is a heterogeneous polysaccharide, and its enzymatic hydrolysis requires endoglucanase, exoglucanase (cellobiohydrolase), and ?-glucosidase to work together. We summarize the most commonly used assays for individual enzymes and cellulase mixture.

Zhang, Y. H. Percival; Hong, Jiong; Ye, Xinhao

235

Nondestructive Evaluation of FRP Bridge Deck Panels  

Microsoft Academic Search

The purpose of this research was to investigate Infrared Thermography (IRT) as a Non-Destructive Evaluation (NDE) method for glass fiber-reinforced polymer (FRP) composite bridge deck panels. FRP bridge decks are currently being evaluated as a potential replacement for traditional steel-grate or concrete bridge decking. A potential problem with these decks, however, is that structural damage that can occur due to

Phillip Hallam

2012-01-01

236

NON-DESTRUCTIVE SOIL CARBON ANALYZER  

Microsoft Academic Search

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

L. MITRA; S. HENDREY; G. ORION; I. ROGERS; H. TORBERT; A. PRIOR; S. RUNION

2004-01-01

237

Coercive force measurements in nondestructive testing  

Microsoft Academic Search

The paper considers applications of coercive force meters with external electromagnets to nondestructive measurements of strength,\\u000a plastic, and viscous properties of rolled high-carbon and low-alloyed steels, characterization of annealed high-carbon, predominantly\\u000a chromium-doped, steels, testing of the quality of quenched and tempered steels, measurements of the depth and hardness of\\u000a surface hardened layers on metallic components, and their use in sorting

G. V. Bida; A. P. Nichipuruk

2000-01-01

238

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

239

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

240

Method of passivating semiconductor surfaces  

DOEpatents

A method of 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, Mark W. (Golden, CO)

1990-01-01

241

Luciferase assay.  

PubMed

When a transient or stable transfection assay is developed for a promoter, a primary objective is to quantify promoter strength. Because transfection efficiency in such assays can be low, promoters are commonly fused to heterologous reporter genes that encode enzymes that can be quantified using highly sensitive assays. The reporter protein's activity or fluorescence within a transfected cell population is approximately proportional to the steady-state mRNA level. A commonly used reporter gene is the luciferase gene from the firefly Photinus pyralis. This gene encodes a 61-kDa enzyme that oxidizes D-luciferin in the presence of ATP, oxygen, and Mg(++), yielding a fluorescent product that can be quantified by measuring the released light. Including coenzyme A in the reaction enhances the sensitivity of the assay and provides a sustained light reaction. In this protocol, cells transfected with a luciferase reporter plasmid are lysed using a detergent-containing buffer. Cell debris is removed by microcentrifugation and luciferase activity is measured using a luminometer. Some luminometers directly inject the reagents into the cell lysate. Such automation allows the signal to be measured at a precise time following injection, which can increase the consistency of the results. For manual luminometers, the substrate solution is mixed by hand with the cell lysate, and the fluorescence is read at a defined time following mixing. The luciferase assay is extremely rapid, simple, relatively inexpensive, sensitive, and possesses a broad linear range. PMID:20439408

Smale, Stephen T

2010-05-01

242

Passive solar retrofit guidebook  

SciTech Connect

The steps involved in retrofitting an existing building for passive solar heating are discussed, and include: conservation measures (increasing insulation and furnace efficiency and decreasing infiltration); site analysis for orientation, declination, and shading; glazing (including night insulation and overhangs); and thermal mass. A retrofit analysis is discussed along with details on each of four retrofit types - direct gain, thermal storage walls (Trombe walls and water walls), sunspaces, and thermosiphon air panel. Methods of calculating heat loss and solar retrofit performance are given and illustrated, as are methods of financial analysis, including payback period. Sources of financing are discussed. Marketing of passive solar retrofits is discussed and illustrated by a case study. (LEW)

Not Available

1981-01-01

243

Passive solar applications  

SciTech Connect

Passive solar applications in buildings are described. The major emphasis of the research has been on devising mathematical models to characterize heat flow within buildings, on the validation of these models by comparison with test results, and on the subsequent use of the models to investigate the influence of both various design parameters and the weather on system performance. Results from both test modules and monitored buildings are discussed. Simulation analysis, the development of simplified methods, and systems analysis are outlined. Passive solar potential in China is discussed.

Balcomb, J.D.

1985-01-01

244

Nondestructive measurements on spent fuel for the nuclear fuel cycle  

SciTech Connect

Nondestructive measurements on spent fuel are being developed to meet safeguards and materials managment requirements at nuclear facilities. Spent-fuel measurement technology and its applications are reviewed.

Cobb, D.D.; Phillips, J.R.

1980-01-01

245

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

246

Passive Buoyancy System.  

National Technical Information Service (NTIS)

The objective of the study is to procure one passive buoyancy system to meet the total requirements for 610,000 lbs. net buoyancy between 500 feet and 13,000 feet water depth. The total system may be comprised of one or more types of buoys, and if a combi...

1966-01-01

247

Passive Bipedal Running  

Microsoft Academic Search

Human-like running is a natural dynamic mode of a simple mechanical biped. Such a machine consists of two telescoping legs with linear springs, connected by a hip joint with a torsional spring. It will run passively; no pattern of forcing is required to generate the gait. With careful design its energy consumption can approach zero, but in any case the

Tad McGeer

1990-01-01

248

Polymeric passive laser shutters  

Microsoft Academic Search

Passive laser shutters are designed to control laser pulse duration by the regulation of the Q-factor through the use of substances which change in transparency upon exposure to light. The present paper outlines the development of such a shutter composed of a radiation-resistant modified polymethyl methacrylic matrix which may be filled with different clear dyes. Experiments performed using a nickel

D. A. Gromov; K. M. Diumaev; A. A. Manenkov; A. P. Masliukov; G. A. Matiushin; V. S. Nechitailo; A. M. Prokhorov

1982-01-01

249

Passive thermosiphon solar collector  

Microsoft Academic Search

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

1984-01-01

250

Passive hydrogel fuel generator  

SciTech Connect

A passive hydrogen oxygen generator in which the long wavelength infrared portion of the sun's spectrum heats water to provide circulation of the water within the generator. The shorter wavelength portion of the spectrum to which water is transparent is used in splitting water into hydrogen and oxygen by photoelectrolysis.

Neefe, Ch. W.

1985-04-16

251

Passive Dynamic Running  

Microsoft Academic Search

Previous work has considered how springy legs can improve the efficiency of the vertical motions of running, making them into resonant spring-mass oscillations that recycle energy from one step to the next. This paper considers how springy hips can be used to improve the efficiency of the legs' fore and aft swinging motions in running. We have studied a passive

Clay M. Thompson; Marc H. Raiber

1989-01-01

252

Passive Solar Heating Residences.  

National Technical Information Service (NTIS)

Passive solar heating systems can supply a major portion of a house's heating load if properly designed. The four basic concepts used are direct gain, thermal storage in wall or roof, solar greenhouse and convective loop. In most applications some of thes...

W. E. Olson

1979-01-01

253

(Passive Solar Heat). Final Report.  

National Technical Information Service (NTIS)

The overall purpose of the demonstration reported was to encourage consumers to use passive solar heat. There were four primary objectives: to document the effectiveness of a simple passive solar design; to demonstrate the feasibility of individual planni...

P. P. Gula

1981-01-01

254

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

255

Passive Seismic Imaging  

NASA Astrophysics Data System (ADS)

Traditionally, passive seismology connotes the use of earthquake signals from continuously recording receivers. Small time windows around the arrivals of earthquakes are then analyzed in myriad fashion. I will distinguish from this body of work, the notion of passive seismic imaging, which requires no knowledge of the time or characteristics of a source event. Instead, by using the ambient noise in the subsurface with all orders of scattering and thus randomized directionality, passive seismic imaging can produce results analogous to conventional controlled source experiments. Mathematical proof of the concept of passive seismic imaging has been presented in the literature from several foundations. The results reduce to the simple concept of cross-correlating many long recordings within a simultaneously deployed array. This generates panels with the kinematics of a shot-gather from a standard reflection seismic acquisition effort. Results from synthetic data sets show the validity of the method for point diffractor, and layered earth models. Noting the similarity of form of the standard approach to produce shot-gathers with the imaging condition of shot-profile migration, I then show that migrating the raw passive seismic data without the correlation step produces the the correct image. The synthetic data from above is used to demonstrate the technique. By comparison, this image is of better quality, and demands less compute time, than migrating the data having been cross-correlated first. Finally, both techniques are used to process a 2x2 meter, 72-channel array recorded on the beach sand of Monterey Bay, California. Approximately one meter below the sand, a six inch diameter plastic pipe was buried to serve as a target.

Artman, B. W.

2003-12-01

256

Dielectric and Magnetic Measurements: A Survey of Nondestructive, Quasi-Nondestructive, and Process-Control Techniques  

Microsoft Academic Search

A review of the most common methods for nondestructive permittivity and permeability measurements is presented. Transmission-line techniques, coaxial apertures, open resonators, surface-waves, and dielectric resonator methods are examined. Measurements on bulk, thin materials, and thin films are addressed. Measurement fixtures that can be used as sensors are highlighted. The frequency range of applicability and typical uncertainties associated with each method

J. Baker-Jarvis; C. Jones; B. Riddle; M. Janezic; R. G. Geyer; J. H. Grosvenor Jr; C. M. Weil

1995-01-01

257

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

258

Applications of Aerospace Technology in Industry a Technology Transfer Profile, Nondestructive Testing.  

National Technical Information Service (NTIS)

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 contributio...

1972-01-01

259

Nondestructive testing standards and the ASME code  

SciTech Connect

Nondestructive testing (NDT) requirements and standards are an important part of the ASME Boiler and Pressure Vessel Code. In this paper, the evolution of these requirements and standards is reviewed in the context of the unique technical and legal stature of the ASME Code. The coherent and consistent manner by which the ASME Code rules are organized is described, and the interrelationship between the various ASME Code sections, the piping codes, and the ASTM Standards is discussed. Significant changes occurred in ASME Sections 5 and 11 during the 1980s, and these are highlighted along with projections and comments regarding future trends and changes in these important documents. 4 refs., 8 tabs.

Spanner, J.C.

1991-04-01

260

Nondestructive pulsed infrared quantitative evaluation of metals  

NASA Astrophysics Data System (ADS)

A nondestructive technique for the quantitative evaluation of defects in metal structures is described. The surface of the metal is irradiated by a short xenon lamp pulse and monitored by a thermal image processor. The analysis relates to the time decay signal of the front face temperature, which contains information on the thermophysical properties and subsurface defects of the material. The time history of the surface temperature is then used to quantify the substructure of the material. Applications for the inspection of aluminum, steel, and turbine blades are presented.

Daniels, Arnold

1996-03-01

261

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

262

Nondestructive evaluation of aircraft fuselage panels with electronic shearography  

Microsoft Academic Search

With the growing number of aging passenger aircraft in the fleet, improve nondestructive inspection (NDI) techniques are being investigated to insure the reliability of the fuselage structures of these aircraft. The Boeing Commercial Airplane Group is evaluating nondestructive testing techniques for detecting disbonds in aircraft structures. One of the techniques under evaluation is electronic shearography. This paper describes the disbond

Morteza Safai

1993-01-01

263

Opportunities and Challenges for Nondestructive Residual Stress Assessment  

Microsoft Academic Search

For a long time, nondestructive residual stress assessment has been one of the greatest opportunities as well as one of the greatest challenges for the NDE community, and probably it will remain so in the foreseeable future. The most critical issue associated with nondestructive residual stress assessment seems to be that of selectivity. Numerous NDE methods have been found to

P. B. Nagy

2006-01-01

264

Applications of the wavefield transform to nondestructive evaluation  

Microsoft Academic Search

Eddy current nondestructive techniques offer many attractive benefits such as reduced inspection time, low cost and reproducibility. Nevertheless, they are not used in many industrial applications, primarily due to the difficulty associated with the lack of simple and physically meaningful interpretation techniques. In contrast; wave propagation phenomena based non-destructive evaluation (NDE) techniques employ a host of physical intuitive concepts, among

Yong Tian

2005-01-01

265

Why We Need Non-Destructive Testing of Welded Constructions  

Microsoft Academic Search

Most process plant and a great deal of structural steelwork for the nuclear, petrochemical, power generation and gas industries is fabricated with the use of fusion welding. Imperfections occur in such welds, due to problems with materials, procedures and techniques, and non-destructive testing is employed to detect such imperfections. The two principal reasons for the use of non-destructive testing are

J. G. Young

1979-01-01

266

Nondestructive dynamic testing of apples for firmness evaluation  

Microsoft Academic Search

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

I Shmulevich; N Galili; M. S Howarth

2003-01-01

267

Nondestructive methods for the structural evaluation of wood floor ...  

Treesearch

Nondestructive techniques for evaluating the structural integrity of wood floor systems in ... ultrasonic, and stress-wave transmission techniques were evaluated in an effort to assess and predict the residual performance of in-place wood floors. ... Nondestructive methods for the structural evaluation of wood floor systems in ...

268

Diagnoses of AC Generator Insulation Condition by Nondestructive Tests  

Microsoft Academic Search

Data are presented from comparison of nondestructive and destructive tests on several synchronous generator stators ranging from 800 to 33,000 kva. It is shown that the breakdown voltage of the weakest point in a winding can be forecast nondestructively by insulation resistance tests at increasing voltages. A new method of stating dielectric-absorption effect is suggested and its value as a

A. W. W. Cameron

1952-01-01

269

Nondestructive evaluation techniques for enhanced bridge inspection  

SciTech Connect

Nondestructive evaluation of bridges is a critical aspect in the US aging infrastructure problem. For example in California there are 26,000 bridges, 3000 are made of steel, and of the steel bridges, 1000 are fracture critical. California Department of Transportation (Caltrans), Federal Highway Administration, and Lawrence Livermore National Laboratory (LLNL) are collaborating to develop and field NDE techniques to improve bridge inspections. We have demonstrated our NDE technologies on several bridge inspection applications. An early collaboration was to ultrasonically evaluate the steel pins in the E-9 pier on the San Francisco Bay Bridge. Following the Loma-Prieta earthquake in 1989 and the road way collapse at the E-9 pier, a complete nondestructive evaluation was conducted by Caltrans inspectors and several ultrasonic indications were noted. LLNL worked with Caltrans to help identify the source of these reflections. Another project was to digitally enhance high energy radiographs of bridge components such as cable end caps. We demonstrated our ability to improve the detection of corrosion and fiber breakage inside the end cap. An extension of this technology is limited view computer tomography (CT). We implemented our limited view CT software and produced cross-sectional views of bridge cables from digitized radiographic films. Most recently, we are developing dual band infrared imaging techniques to assess bridge decks for delaminations. We have demonstrated the potential of our NDE technology for enhancing the inspection of the country`s aging bridges.

Thomas, G.; Benson, S.; Durbin, P.; Del Grande, N.; Haskins, J.; Brown, A.; Schneberk, D.

1993-10-01

270

Nonlinear acoustic nondestructive testing for concrete durability  

NASA Astrophysics Data System (ADS)

Several nondestructive testing methods can be used to determine the damage in a concrete structure. Linear ultrasonic techniques, e.g. pulse-velocity and amplitude attenuation, are very common in nondestructive evaluation. Velocity of propagation is not very sensitive to the degrees of damage unless a great deal of micro-damage having evolving into localized macro-damage. This transition typically takes place around 80% of the ultimate compressive strength. Amplitude attenuation is potentially more sensitive than pulse-velocity. However, this method depends strongly on the coupling conditions between transducers and concrete, hence unreliable. A baseline test of the linear acoustics of several mortar samples was conducted. These mortar samples have been previously damaged to different levels. Several other testing methods were also performed on the same samples to form a comparison. The focus is in comparing the sensitivity of a new testing method (Non-linear Acoustic NDE) with several more traditional testing methods. Non-linearity of the material stiffness is expressed in non-linear acoustics as the effect that damage and flaws have on the modulation of a signal as it propagates through the material. Spectral (non-linear) analysis is much more sensitive to lower damage states and less dependent on the repeatability of the coupling of the transducers.

Wu, Hwai-Chung; Warnemuende, Kraig

2000-06-01

271

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

272

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

273

Passive optoelectronic tag  

NASA Astrophysics Data System (ADS)

In response to a pressing demand for tagging systems and technologies developing, Physical Optics Corporation (POC) proposes a novel Passive Optoelectronical (POET) Tag system. The POET tag is an omnidirectional (360° in azimuth), with up to 180° field-of-view in elevation, retroreflection optical system with a high frequency multiple quantum well (MQW) light intensity modulator for free space IR optical communication. The POET tag optical scheme is a compact, high quality generalized fish-eye lens with telecentric arrangement in image space. The telecentric arrangement in image space provides perfect omnidirectional retroreflection of a recall beam and an optimum divergent of light at the MQW providing maximum modulation contrast ratios. The important POET tag features are low power consumption, zero probability of jamming and intercepting (high security of communication,) because it operates in a passive retroreflection mode with a highly-directed optical beam.

Agurok, Il'ya P.; Jannson, Tomasz P.; Savant, Gajendra D.

2003-09-01

274

Passive fetal monitoring sensor  

NASA Astrophysics Data System (ADS)

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.; Hall, Earl T.; Baker, Donald A.; Bryant, Timothy D.

1992-08-01

275

Passive fetal monitoring sensor  

NASA Astrophysics Data System (ADS)

The invention is an ambulatory, passive sensor for use in a fetal monitoring system. The invention incorporates 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 from a fetus inside an expectant mother and to provide means for filtering out pressure pulses arising from other sources, such as the maternal heart.

1990-07-01

276

Nanoimprinted passive optical devices  

Microsoft Academic Search

We report on the feasibility and process parameters of nanoimprint lithography to fabricate low refractive index passive optical devices. Diffraction gratings printed in polymethylmethacrylate (PMMA) exhibit a sharp dispersion with a full width at half maximum of about 20 nm. Waveguides were printed in polystyrene (PS) on silicon oxide and had losses between 8-20 dB cm-1 at wavelengths between 650-400

J. Seekamp; S. Zankovych; A. H. Helfer; P. Maury; C. M. Sotomayor Torres; G. Böttger; C. Liguda; M. Eich; B. Heidari; L. Montelius; J. Ahopelto

2002-01-01

277

Passive acoustics as a monitoring tool for evaluating oyster reef restoration  

NASA Astrophysics Data System (ADS)

Oyster reefs are biodiverse communities that provide many ecological and commercial benefits. However, oyster reefs have declined around the world from human activities. Oyster reef restoration programs have begun to limit some of the decline, but the need for determining the success of a program has been problematic. Passive acoustic techniques can use naturally occurring sounds produced by organisms to assess biodiversity. Passive acoustics was utilized to compare the sounds in natural and restored oyster reefs, with special attention on snapping shrimp (Alpheus spp.) snap sounds, in the St. Lucie Estuary, Florida over a one year period. Season, estuary region, habitat and day period had an effect on sound production Passive acoustic monitoring of snapping shrimp sound production may be a useful non-destructive technique for monitoring the progress of oyster reef restoration projects once further correlations are established between environmental effects and sound production.

Zenil Becerra, Hilde P.

278

SWEPP Assay System Version 2.0 software test plan and report  

SciTech Connect

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

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

1996-07-01

279

Dielectric and magnetic measurements: A survey of nondestructive, quasi-nondestructive, and process-control techniques  

Microsoft Academic Search

A review of the most common methods for nondestructive permittivity and permeability measurements is presented. Transmission-line\\u000a techniques, coaxial apertures, open resonators, surface-waves, and dielectric resonator methods are examined. Measurements\\u000a on bulk, thin materials, and thin films are addressed. Measurement fixtures that can be used as sensors are highlighted. The\\u000a frequency range of applicability and typical uncertainties associated with each method

J. Baker-Jarvis; C. Jones; B. Riddle; M. Janezic; R. G. Geyer; J. H. Grosvenor; C. M. Weil

1995-01-01

280

Computer modeling of eddy current nondestructive testing  

SciTech Connect

Nondestructive evaluation (NDE) is to materials what CAT scanning is to the human body--an attempt to look inside without opening up the body. As in CAT scanning, modern NDE requires sophisticated mathematical software to perform its function. This is especially true with regard to quantitative NDE, wherein an attempt is made to quantify defects, that is, determine their size, location, and even shape rather than just to detect their presence. Low-frequency electromagnetic methods using eddy currents are a traditional mode of doing NDE (approximately 35 percent of NDE uses eddy currents, depending upon the specific application), but the technology still suffers from a lack of algorithms and software to allow its full potential to be realized. In this article the authors will describe a computer code that was developed to alleviate that problem.

Sabbagh, H.A.; Treece, J.C.; Murphy, R.K.; Woo, Lai Wan (Sabbagh Association, Inc., Bloomington, IN (United States))

1993-11-01

281

Nondestructive evaluation of nuclear-grade graphite  

NASA Astrophysics Data System (ADS)

The material of choice for the core of the high-temperature gas-cooled reactors being developed by the U.S. Department of Energy's Next Generation Nuclear Plant Program is graphite. Graphite is a composite material whose properties are highly dependent on the base material and manufacturing methods. In addition to the material variations intrinsic to the manufacturing process, graphite will also undergo changes in material properties resulting from radiation damage and possible oxidation within the reactor. Idaho National Laboratory is presently evaluating the viability of conventional nondestructive evaluation techniques to characterize the material variations inherent to manufacturing and in-service degradation. Approaches of interest include x-ray radiography, eddy currents, and ultrasonics.

Kunerth, D. C.; McJunkin, T. R.

2012-05-01

282

Problems associated with nondestructive evaluation of bridges  

NASA Astrophysics Data System (ADS)

The US has 542,000 bridges that consume billions of dollars per year in construction, rehabilitation, and maintenance funds and which are the lifelines of US commerce. The 1992 ISTEA (Intermodal Surface Transportation Efficiency Act) mandates the implementation of a quantitative computerized bridge management system by 1996. A prime need of such a system are quantitative bridge inspection methods to feed accurate reliable condition information to the huge database of bridges. Nondestructive evaluation (NDE) will fill a critical need in the implementation of effective bridge management. However, many serious barriers exist to the widespread routine application of this technology to bridges. This paper provides an overview of the typical problems associated with applying NDE to bridges.

Prine, David W.

1995-05-01

283

Projection Registration Applied to Nondestructive Testing  

SciTech Connect

Registration of radiographic and computed tomography (CT) data has the potential to allow automated metrology and defect detection. While registration of the three-dimensional reconstructed data is a common task in the medical industry for registration of data sets from multiple detection systems, registration of projection sets has only seen development in the area of tomotherapy. Efforts in projection registration have employed a method named Fourier phase matching (FPM). This work discusses implementation and results for the application of the FPM method to industrial applications for the nondestructive testing (NDT) community. The FPM method has been implemented and modified for industrial application. Testing with simulated and experimental x-ray CT data shows excellent performance with respect to the resolution of the imaging system.

Bingham, Philip R [ORNL; Arrowood, Lloyd [Y-12 National Security Complex

2010-01-01

284

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

285

Projection registration applied to nondestructive testing  

NASA Astrophysics Data System (ADS)

Registration of radiographic and computed tomography (CT) data has the potential to allow automated metrology and defect detection. While registration of the three-dimensional reconstructed data is a common task in the medical industry for registration of data sets from multiple detection systems, registration of projection sets has only seen development in the area of tomotherapy. Efforts in projection registration have employed a method named Fourier phase matching (FPM). This work discusses implementation and results for the application of the FPM method to industrial applications for the nondestructive testing (NDT) community. The FPM method has been implemented and modified for industrial application. Testing with simulated and experimental x-ray CT data shows excellent performance with respect to the resolution of the imaging system.

Bingham, Philip; Arrowood, Lloyd

2010-07-01

286

Practical applications of nondestructive materials characterization  

NASA Astrophysics Data System (ADS)

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

Green, Robert E., Jr.

1992-10-01

287

Fundamental studies of passivity and passivity breakdown. Final report  

SciTech Connect

This report summarizes the findings of our fundamental research program on passivity and passivity breakdown. During the past three and one half years in this program (including the three year incrementally-funded grant prior to the present grant), we developed and experimentally tested various physical models for the growth and breakdown of passive films on metal surfaces. These models belong to a general class termed ``point defects models`` (PDMs), in which the growth and breakdown of passive films are described in terms of the movement of anion and cation vacancies.

Macdonald, D.D.; Urquidi-Macdonald, M.; Song, H.; Biaggio-Rocha, S.; Searson, P.

1991-11-01

288

Optically addressed ferroelectric memory with nondestructive readout  

NASA Astrophysics Data System (ADS)

We present a review of the emerging optically addressed ferroelectric memory with nondestructive readout as a nonvolatile memory technology, identify its high-impact applications, and project on some novel device designs and architectures that will enable its realization. Based on the high-speed bidirectional polarization-dependent photoresponse, simulation of a readout circuit for a 16-kbit VLSI ferromemory chip yields read-access times of approximately 20 ns and read-cycle times of approximately 30 ns ( approximately 34 ns and approximately 44 ns, respectively, within a framework of a radiation-hard environment), easily surpassing those of the conventional electrical destructive readout. Extension of the simulation for a 64-kbit memory shows that the read-access and -cycle times are only marginally increased to approximately 21 ns and approximately 31 ns, respectively ( approximately 38 ns and approximately 48 ns, with a radiation-hard readout circuitry). Commercial realization of the optical nondestructive readout, however, would require a reduction in the incident (optical) power by roughly an order of magnitude for the readout or an enhancement in the delivered power-to-size ratio of semiconductor lasers for compact implementation. We present a new two-capacitor memory-cell configuration that provides an enhanced bipolar optoelectronic response from the edges of the capacitor at incident power as low as approximately 2 mW/ mu m 2. A novel device design based on lead zirconate titanate with the c axis parallel to the substrate is suggested to reduce the requirement of incident optical power further by

Thakoor, Sarita; Thakoor, Anil P.

1995-06-01

289

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

290

Expansion of passive safety function  

SciTech Connect

Expansion of the use of passive safety functions is proposed. Two notions are presented. One is that, in the design of passive safety nuclear reactors where aversion of active components is stressed, some active components are purposely introduced, by which a system is built in such a way that it behaves in an apparently passive manner. The second notion is that, instead of using a passive safety function alone, a passive safety function is combined with some active components, relating the passivity in the safety function with enhanced controllability in normal operation. The nondormant system which the authors propose is one example of the first notion. This is a system in which a standby safety system is a portion of the normal operation system. An interpretation of the nondormant system via synergetics is made. As an example of the second notion, a PIUS density lock aided with active components is proposed and is discussed.

Inai, Nobuhiko; Nei, Hiromichi; Kumada, Toshiaki

1995-07-01

291

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

292

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

293

Surface passivation optimization using DIRECT  

SciTech Connect

We describe a systematic and efficient method of determining pseudo-atom positions and potentials for use in nanostructure calculations based on bulk empirical pseudopotentials (EPMs). Given a bulk EPM for binary semiconductor X, we produce parameters for pseudo-atoms necessary to passivate a nanostructure of X in preparation for quantum mechanical electronic structure calculations. These passivants are based on the quality of the wave functions of a set of small test structures that include the passivants. Our method is based on the global optimization method DIRECT. It enables and/or streamlines surface passivation for empirical pseudopotential calculations.

Graf, Peter A. [National Renewable Energy Laboratory (NREL), Golden, CO 80401 (United States)]. E-mail: peter_graf@nrel.gov; Kim, Kwiseon [National Renewable Energy Laboratory (NREL), Golden, CO 80401 (United States); Jones, Wesley B. [National Renewable Energy Laboratory (NREL), Golden, CO 80401 (United States); Wang, Lin-Wang [Computational Research Division, Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA 94720 (United States)

2007-06-10

294

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

295

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

296

Passive ocean acoustic tomography  

NASA Astrophysics Data System (ADS)

The possibility to apply natural acoustic ocean noise in the ocean and noise of distant vessels as sounding signals in order to determine the physical parameters of a water layer is considered in this paper. We developed the methods making it possible to suppress the non-diffuse components of noise produced, e.g., by local vessels and to account for hydrophone motion. These methods are applied to the noise records obtained in the course of a year-long experiment on long-range sound propagation in the Pacific Ocean. We confirmed experimentally our theoretical predictions as to the possibility of retrieving deterministic acoustic ray travel times in a nonuniform environment from a mutual correlation function of imperfectly diffuse (gradually anisotropic and spatially nonuniform) noise without invoking any data on its source. We performed passive measurements of sound velocity in the ocean with a relative error of about 0.1% by correlation of noise fields recorded with vertical aerials. This accuracy approaches that needed for oceanological applications. Further investigations are necessary to study the feasibility of passive acoustic tomography and thermometry in the ocean at distances of tens and hundreds of kilometers and the possibility to use simpler arrays not equipped with hydrophone positioning systems.

Godin, O. A.; Goncharov, V. V.; Zabotin, N. A.

2012-05-01

297

Fundamental studies of passivity and passivity breakdown. Final report.  

National Technical Information Service (NTIS)

This report summarizes the findings of our fundamental research program on passivity and passivity breakdown. During the past three and one half years in this program (including the three year incrementally-funded grant prior to the present grant), we dev...

D. D. Macdonald M. Urquidi-Macdonald H. Song S. Biaggio-Rocha P. Searson

1991-01-01

298

Commentary on "Capturing the Evasive Passive"  

ERIC Educational Resources Information Center

|Passives has been the focus of much research in language acquisition since the 1970s. It has been clear from this research that young children seldom produce passives spontaneously, particularly "long" or "full" passives with a by-phrase; and they usually perform poorly on experimental tests of the comprehension of passives, especially passives…

Lillo-Martin, Diane; Snyder, William

2009-01-01

299

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

300

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

301

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

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

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

302

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

303

Application of Computerized Tomography for Nondestructive Evaluation of Weldments.  

National Technical Information Service (NTIS)

The purpose of this research project has been to investigate the feasibility of applying the Computerized Tomographic (CT) processes to the nondestructive testing and evaluation of weldments. The present study investigates the degree of spatial resolution...

I. L. Morgan S. Gautam

1983-01-01

304

Nondestructive, Fast Methods for Burn-Up Study.  

National Technical Information Service (NTIS)

Nondestructive methods, based on high resolution-spectrometry successfully applied at Institute for Atomic Physics are presented. These methods are preferred to destructive chemical methods; the latter being costly and lengthy and not suitable for statist...

L. Schaechter D. Hacman O. Mot

1977-01-01

305

Overview of Mathematical Modeling in Nondestructive Evaluation (NDE).  

National Technical Information Service (NTIS)

This report presents a broad overview of mathematical modeling in nondestructive evaluation (NDE). The primary emphasis is to expand the review of NDE modeling literature covered by previous general works. To provide a starting point for researchers and e...

J. C. Aldrin

2002-01-01

306

Nondestructive Evaluation of Damage in Metal Matrix Composites.  

National Technical Information Service (NTIS)

The basic objectives of this work were: to apply nondestructive evaluation techniques to metal matrix composites; to obtain base line data as to the ability of these techniques to locate, identify and quantify defects in these materials; to determine the ...

E. G. Henneke K. L. Reifsnider W. W. Stinchcomb J. C. Duke

1979-01-01

307

Nondestructive evaluation of thick-composite fatigue damage  

NASA Astrophysics Data System (ADS)

This paper describes the results of the comparison of a variety of nondestructive evaluation techniques to monitor the development of fatigue damage in thick graphite/epoxy composites. Three inch long, one inch square cross-section test specimens were fatigue tested in compression. Most specimens incorporated stress (strain) concentration notches at their mid- section in order to localize the primary fatigue damage regions in an optimum location for nondestructive monitoring. The nondestructive techniques evaluated were ultrasonic B- and C- scan, ultrasonic velocity and attenuation, ultrasonic second harmonic generation, acoustic microscopy, acoustic emission, thermography, real-time high-speed digital/video laser speckle decorrelation, magnetic resonance imaging, radio-opaque penetrant enhanced x-radiography, and eddy current. Mechanical resonance spectroscopy was used to measure the second order (linear) elastic moduli. Optical and electron microscopy on cut and polished specimens were used to verify the results of the nondestructive tests.

Green, Robert E.

1995-06-01

308

Use of Nondestructive Testing Technique as a Routine Inspection Procedure.  

National Technical Information Service (NTIS)

A feasibility study for utilizing proven nondestructive testing techniques in the routine periodic inspection and evaluation of bridges is presented. The inspection procedure, intended for bridges to be built, will enable engineers to obtain a quantitativ...

M. S. Aggour H. M. Fouad

1991-01-01

309

Development of Nondestructive Testing Techniques for High Performance Ceramics.  

National Technical Information Service (NTIS)

Two ceramic materials, a hot-pressed silicon nitride and a siliconized silicon carbide, were manufactured with seeded particulates to evaluate the effectiveness of existing nondestructive test practices for defect detection in ceramics and to evaluate the...

H. R. Baumgartner R. H. Brockelman P. M. Hanson

1978-01-01

310

Technologies for Nondestructive Evaluation of Surfaces and Thin Coatings.  

National Technical Information Service (NTIS)

The effort included in this project included several related activities encompassing basic understanding, technological development, customer identification and commercial transfer of several methodologies for nondestructive evaluation of surfaces and thi...

1999-01-01

311

Portable Sorption Tester for NOndestructive Testing of Chemical Protective Garments.  

National Technical Information Service (NTIS)

A prototype portable instrument was developed to measure, nondestructively, sorptive capacity of chemical protective garments in the field. The instrument contains four major subsystems: flow control, .detection, microprocessor controller, and sample cell...

S. Kerrin E. Klemperer

1992-01-01

312

Non-Destructive Inspection Techniques for Acrylic Canopies.  

National Technical Information Service (NTIS)

The advantages and necessities of non-destructive inspection (NDI) of aircraft structural components have gained wide recognition in the aerospace industry. This extends to evaluation of transparent enclosure materials in which the structural adequacy and...

G. F. Thomas S. I. Shelton

1976-01-01

313

Evaluation of Nondestructive Testing Techniques of Diffusion Coatings.  

National Technical Information Service (NTIS)

Three novel nondestructive testing methods of diffusion coatings were compared with other methods and checked against microscopic examination by subsequent sectioning of suspected defects. Methods used consisted of a beta backscatter, X-ray fluorescence a...

B. E. Arnesen H. B. Karplus R. A. Semmler

1968-01-01

314

Nondestructive Testing and Identification for Bridge Rating: Pilot Project.  

National Technical Information Service (NTIS)

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

A. E. Aktan M. Raghavendrachar

1990-01-01

315

HPAT: A nondestructive analysis technique for plutonium and uranium solutions.  

National Technical Information Service (NTIS)

Two experimental approaches for the nondestructive characterization of mixed solutions of plutonium and uranium, developed at ENEA (Italian Commission for Alternative Energy Sources) Research Centre of Casaccia, with the goal of measuring low plutonium co...

B. Mattia F. V. Frazzoli M. Aparo P. Zeppa V. Pagliai

1989-01-01

316

Nondestructive Evaluation of Creep-Fatigue Damage: An Interim Report.  

National Technical Information Service (NTIS)

In view of the uncertainties involved in designing against creep-fatigue failure and the consequences of such failures in Class 1 nuclear components that operate at elevated temperature, the possibility of intermittent or even continuous non-destructive e...

R. E. Nickell

1977-01-01

317

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

318

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

319

Non-destructive diffraction enhanced imaging of seeds  

Microsoft Academic Search

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

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

2007-01-01

320

Non-destructive testing of concrete strength: statistical control  

Microsoft Academic Search

Some problems of statistical control of concrete strength in non-destructive testing are considered. The procedures for rejection\\u000a of gross errors and accounting for the actual law of concrete strength distribution are given. In the non-destructive control,\\u000a the reliability and accuracy of a test result, fi, as well as the probability of a specified concrete strength, f?\\u000a c\\u000a , should be

A. M. Leshchinsky

1992-01-01

321

Three-dimensional image construction for non-destructive testing  

Microsoft Academic Search

We propose a fuzzy inference based method to visualize the 3D structure of a tube buried in a concrete. The nondestructive testing (NDT) with pulse-radar, which makes it possible to non-destructively unmask the tubes in a concrete, is one of the most remarkable techniques of NDT. However, only expert can interpret the scanned data. In our work, we represent such

Takashi MATSUMOTO; K. Ohta; Y. Hata; K. Taniguchi

2000-01-01

322

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

323

Non-destructive sampling of Schoenoplectus maritimus in southern France  

Microsoft Academic Search

Above- and belowground biomass of the macrophyte Schoenoplectus maritimus was measured in Camargue (Rhône delta, southern France) using destructive and non-destructive sampling methods. Our aim was\\u000a to validate whether non-destructive sampling could be used for long-term monitoring of marshes subjected to grazing by cattle\\u000a and Greylag geese (Anser anser). Height and diameter explained more than 95% of the variation in

Christophe Gouraud; Jean-François Giroux; François Mesléard; Laurent Desnouhes

2008-01-01

324

Materials for passively safe reactors  

Microsoft Academic Search

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

Simnad

1993-01-01

325

Learning the Passive in Zulu.  

ERIC Educational Resources Information Center

|A study of the late acquisition of the passive in Zulu used data from transcripts of naturalistic speech gathered in a longitudinal study of several children's speech development between 1.10 and 3.6 years of age. It was hypothesized that the productivity of the passive construction in Zulu is a factor facilitating acquisition. A range of…

Suzman, Susan M.

1985-01-01

326

Temperature initiated passive cooling system  

Microsoft Academic Search

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

Charles W

1994-01-01

327

Passive solar heating and analysis  

SciTech Connect

Passive solar heating experience and analysis techniques are reviewed with emphasis on annual auxiliary heat requirement. The role of analysis in the design of passive solar buildings is discussed. Selected results for existing systems are presented for locations in Saudi Arabia and climatically similar locations in the US. Advanced systems in the research stage are described.

Jones, R.W.

1984-01-01

328

Passive vapor extraction feasibility study.  

National Technical Information Service (NTIS)

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.-diamete...

V. J. Rohay

1994-01-01

329

Passive solar: subdivisions, windows, underground  

Microsoft Academic Search

A collection of papers illustrating the use of passive solar design are presented. Solar design is traced from over a century ago to the present. Discussed are design considerations for the mass market, products which enhance the application of passive solar techniques, market and financing problems. Window design is discussed in terms of glass, air infiltration, air movement, thermal transfer

H. Wade; J. Cook; K. Labs; S. Selkowitz

1983-01-01

330

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

331

Adaptive passive fathometer processing.  

PubMed

Recently, a technique has been developed to image seabed layers using the ocean ambient noise field as the sound source. This so called passive fathometer technique exploits the naturally occurring acoustic sounds generated on the sea-surface, primarily from breaking waves. The method is based on the cross-correlation of noise from the ocean surface with its echo from the seabed, which recovers travel times to significant seabed reflectors. To limit averaging time and make this practical, beamforming is used with a vertical array of hydrophones to reduce interference from horizontally propagating noise. The initial development used conventional beamforming, but significant improvements have been realized using adaptive techniques. In this paper, adaptive methods for this process are described and applied to several data sets to demonstrate improvements possible as compared to conventional processing. PMID:20370000

Siderius, Martin; Song, Heechun; Gerstoft, Peter; Hodgkiss, William S; Hursky, Paul; Harrison, Chris

2010-04-01

332

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

333

Stain length passive dosimeters  

SciTech Connect

Passive dosimeters with instant readout capability have been devised by combining the principles of a gas indicator tube with membrane control of mass transfer. The membrane controls the diffusion of the gas or vapour to the reagent-impregnated support where it reacts to produce a stain. Results with H/sub 2/S and benzene monitors demonstrate that time-weighted average concentration of ambient gas or vapour can be measured accurately and precisely by following the movement of the coloured stain in the specially prepared and calibrated indicator tube. The 95% confidence interval of such measurements at the ThV is +/-20% for H/sub 2/S and +/-15% for benzene, well within NI0SH limits of acceptability.

Sefton, M.V.

1982-11-01

334

Stain length passive dosimeters  

SciTech Connect

Passive dosimeters with instant readout capability have been devised by combining the principles of a gas indicator tube with membrane control of mass transfer. The membrane controls the diffusion of the gas or vapor to the reagent impregnanted support where it reacts to produce a stain. Results with H/sub 2/S and benzene monitors demonstrated that time weighted average concentration of ambient gas or vapor can be measured accurately and precisely by following the movement of the colored stain in the specially prepared and calibrated indicator tube. The 95% confidence interval of such measurements at the TLV (80 ppm-hrs) is +/- 20% for H/sub 2/S and +/- 15% for benzene, well within NIOSH limits of acceptability.

Sefton, M.V.; Kostas, A.V.; Lombardi, C.

1982-11-01

335

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

336

Affordable passive solar homes  

SciTech Connect

This book presents plans and designs for residential solar heating or cooling systems that use no external mechanical power to move collected solar heat. The proposed designs range in size from 300 to 1,600 square feet and are based on minimal construction time, minimal materials and labor, optimized utilization, and adaptability of space. Topics considered include home ownership economics, site selection and microclimate, codes and regulations, cross ventilation and inductive airflow, basic building materials, the use of waste or salvageable materials, construction procedures, interiors, daylighting, control over noise, indoor air quality, compact homes, midsized homes, multiple homes, ultracompact homes, and survival homes. The passive solar home plans presented are principally designed for the large temperate and cold-climate zones of the continental United States.

Vrowther, R.L.

1984-01-01

337

Inhomogeneous anisotropic passive scalars  

NASA Astrophysics Data System (ADS)

We investigate the behaviour of the two-point correlation function in the context of passive scalars for non-homogeneous, non-isotropic forcing ensembles. Exact analytical computations can be carried out in the framework of the Kraichnan model for each anisotropic sector. We will focus our attention on the isotropic sector with isotropic forcing in order to obtain a description of the influence of purely inhomogeneous contributions. It is shown how the homogeneous solution is recovered at separations smaller than an intrinsic typical lengthscale induced by inhomogeneities, and how the different Fourier modes in the centre-of-mass variable recombine themselves to give a ‘beating’ (superposition of power laws) described by Bessel functions. The pure power-law behaviour is restored even if the inhomogeneous excitation takes place at very small scales.

Martins Afonso, M.; Sbragaglia, M.

338

Passive tamper-indicating secure container.  

National Technical Information Service (NTIS)

This paper describes a passive tamper-indicating secure container that has been designed to demonstrate concepts, features, and materials that can be used in passive container applications. (In a passive security system, physical phenomena provide visual ...

J. C. Bartberger

1993-01-01

339

Nondestructive Analysis of Telescope Surfaces and Coatings  

NASA Astrophysics Data System (ADS)

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

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

2010-10-01

340

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

341

Nondestructive evaluation development for process control  

SciTech Connect

A joint project between Garrett Ceramic Components (GCC) of Allied Signal Aerospace Corporation and Argonne National Laboratory (ANL) is ongoing to evaluate nondestructive characterization (NDC) methods to detect and measure process-induced variations in ceramic materials. The process methods of current focus on slip-casting and injection molding and the NDC methods being evaluated are microfocus X-ray computed tomography (XCT) and nuclear magnetic resonance computed tomography (MRCT). As part of this work, SiC whisker reinforced Si{sub 3}N{sub 4} (GCC`s GN-10 material) has been pressure slip-cast at two casting pressures, 15 and 40 psi; and at length/diameter ratios of 1.5, 2.5 and 3.0 with whisker contents of 20, 23, 27 and 30 wt %. Three-dimensional microfocus XCT has been used to study density variations in billets produced by different process conditions. Destructive measurement of density variation has been compared to the XCT measurements and correlations established. XCT has been shown to be able to detect <5% variations in as-cast density and these were destructively verified.

Ellingson, W.A.; Holloway, D.L.; Sivers, E.A. [Argonne National Lab., IL (United States); Ling, J. [Chinese Academy of Science, Shanghai SH (China). Inst. for Ceramics; Pollinger, J.P.; Yeh, H.C. [Allied-Signal Aerospace Co., Torrance, CA (United States). Garrett Ceramic Components Div.

1991-12-31

342

Nondestructive evaluation development for process control  

SciTech Connect

A joint project between Garrett Ceramic Components (GCC) of Allied Signal Aerospace Corporation and Argonne National Laboratory (ANL) is ongoing to evaluate nondestructive characterization (NDC) methods to detect and measure process-induced variations in ceramic materials. The process methods of current focus on slip-casting and injection molding and the NDC methods being evaluated are microfocus X-ray computed tomography (XCT) and nuclear magnetic resonance computed tomography (MRCT). As part of this work, SiC whisker reinforced Si{sub 3}N{sub 4} (GCC's GN-10 material) has been pressure slip-cast at two casting pressures, 15 and 40 psi; and at length/diameter ratios of 1.5, 2.5 and 3.0 with whisker contents of 20, 23, 27 and 30 wt %. Three-dimensional microfocus XCT has been used to study density variations in billets produced by different process conditions. Destructive measurement of density variation has been compared to the XCT measurements and correlations established. XCT has been shown to be able to detect <5% variations in as-cast density and these were destructively verified.

Ellingson, W.A.; Holloway, D.L.; Sivers, E.A. (Argonne National Lab., IL (United States)); Ling, J. (Chinese Academy of Science, Shanghai SH (China). Inst. for Ceramics); Pollinger, J.P.; Yeh, H.C. (Allied-Signal Aerospace Co., Torrance, CA (United States). Garrett Ceramic Components Div.)

1991-01-01

343

Nondestructive characterization of structural ceramic components  

SciTech Connect

Advanced structural ceramic components under development for heat-engine applications include both monolithic and continuous fiber composites (CFC). Nondestructive characterization (NDC) methods being developed differ for each material system. For monolithic materials, characterization during processing steps is important. For many CFC, only post process characterization is possible. Many different NDC systems have been designed and built A 3D x-ray micro computed tomographic (3DXCT) imaging system has been shown to be able to map density variations to better than 3% in pressure slip cast Si{sub 3}N{sub 4} monolithic materials. In addition, 3DXCT coupled to image processing has been shown to be able to map through-thickness fiber orientations in 2D lay-ups of 0{degrees}/45{degrees}, 0{degrees}/75{degrees}, 0{degrees}/90{degrees}, in SiC/SiC CVI CFC. Fourier optics based laser scatter systems have been shown to be able to detect surface and subsurface defects (as well as microstructural variations) in monolithic Si{sub 3}N{sub 4} bearing balls. Infrared methods using photothermal excitation have been shown to be able to detect and measure thermal diffusivity differences on SiC/SiC 2D laminated CFC which have been subjected to different thermal treatments including thermal shock and oxidizing environments. These NDC methods and their applications help provide information to allow reliable usage of ceramics in advanced heat engine applications.

Ellingson, W.A.; Steckenrider, J.S.; Sivers, E.A. [Argonne National Lab., IL (United States); Ling, J.R. [Chinese Academy of Sciences, Shanghai, SH (China). Shanghai Inst. of Ceramics

1994-06-01

344

Nondestructive evaluation of advanced ceramic composite materials  

SciTech Connect

Nondestructive evaluation techniques were developed to characterize performance degrading conditions in continuous fiber-reinforced silicon carbide/silicon carbide composites. Porosity, fiber-matrix interface bond strength, and physical damage were among the conditions studied. The material studied is formed by chemical vapor infiltration (CVI) of the matrix material into a preform of woven reinforcing fibers. Acoustic, ultrasonic, and vibration response techniques were studied. Porosity was investigated because of its inherent presence in the CVI process and of the resultant degradation of material strength. Correlations between porosity and ultrasonic attenuation and velocity were clearly demonstrated. The ability of ultrasonic transmission scanning techniques to map variations in porosity in a single sample was also demonstrated. The fiber-matrix interface bond was studied because of its importance in determining the fracture toughness of the material. Correlations between interface bonding and acoustic and ultrasonic properties were observed. These results are presented along with those obtained form acoustic and vibration response measurements on material samples subjected to mechanical impact damage. This is the final report on research sponsored by the US Department of Energy, Fossil Energy Advanced Research and Technology Development Materials Program. 10 refs., 24 figs., 2 tabs.

Lott, L.A.; Kunerth, D.C.; Walter, J.B.

1991-09-01

345

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

346

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

347

FTIR spectrophotometric methods used for antioxidant activity assay IN MEDICINAL PLANTS  

Microsoft Academic Search

Fourier transform infrared spectroscopy (FTIR) is a fast and nondestructive analytical method. Associated with chemometrics, it is a powerful tool for research and industry. The present review discusses the antioxidant activities assay of some plants (fruits, leaves, aerian part) having medical properties using FTIR spectrophotometric method in comparison with other UV-VIS different spectrophotometric methods. A good correlation was found between

Andrei A. Bunaciu; Hassan Y. Aboul-Enein; Serban Fleschin

2012-01-01

348

Seafloor nuclear magnetic resonance assay of methane hydrate in sediment and rock  

Microsoft Academic Search

Proton nuclear magnetic resonance (NMR) of liquid water can be used to indirectly detect and assay methane hydrate in opaque earth materials. It is also potentially useful for quantifying pore size control of hydrate formation, and for estimating in situ hydraulic permeability of hydrate-affected earth formations. The method is quantitative, nondestructive, and volumetrically averaging over a spatially selected region. In

R. L. Kleinberg; C. Flaum; C. Straley; P. G. Brewer; G. E. Malby; E. T. Peltzer; G. Friederich; J. P. Yesinowski

2003-01-01

349

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

350

Guided wave nuances for ultrasonic nondestructive evaluation.  

PubMed

Recent developments in guided wave generation, reception, and mode control show that increased penetration power and sensitivity are possible. A tone burst function generator and appropriate signal processing are generally used. Variable angle beam and comb-type transducers are the key to this effort. Problems in tubing, piping, hidden corrosion detection in aging aircraft, adhesive and diffusion bonding, and ice detection are discussed. Additionally, sample configurations, inspection objectives, and logic are being developed for such sample problems as defect detection and analysis in lap splice joints, tear straps, cracks in a second layer, hidden corrosion in multiple layers, cracks from rivet holes, transverse cracking in a beam, and cracks in landing gear assembly. Theoretical and experimental aspects of guided wave analysis include phase velocity, group velocity, and attenuation dispersion curves; boundary element model analysis for reflection and transmission factor analysis; use of wave structure for defect detection sensitivity; source influence on the phase velocity spectrum, and the use of angle beam and comb transducer technology. Probe design and modeling considerations are being explored. Utilization of in-plane and out-of-plane displacement patterns on the surface and longitudinal power distribution across the structural cross-section are considered for improved sensitivity, penetration power, and resolution in nondestructive evaluation. Methods of controlling the phase velocity spectrum for mode and frequency selection are available. Such features as group velocity change, mode cut-off measurements, mode conversion, amplitude ratios of transmission, and reflection factors of specific mode and frequency as input will be introduced for their ability to be used in flaw and material characterization analysis. PMID:18238584

Rose, J L

2000-01-01

351

Laser speckle photometry: contactless nondestructive testing technique  

NASA Astrophysics Data System (ADS)

Laser Speckle Photometry (LSP) is a newly developed contactless, fast and completely optical nondestructive testing method based on the detection and analysis of thermally or mechanically activated characteristic speckle dynamics. The heat propagation or tension process causes locally different degrees of thermal/mechanical expansion, which generates local and time-dependent strain fields, resulting in a local displacement of material surface. During this process, the normal surface slope and absolute height of the microscopic and mesoscopic surface segments, especially at rough sample surfaces, is transformed. These spatiotemporal changes include information about the material structure and conditions. Therefore, the proposed measurement technique includes a pulsed heating source for sample activation, a temperature detection of the sample at the measurement location in a distance from the heading point, a continuous wave laser for sample irradiation and activation of speckle patterns at the measurement point, and in addition, a fast CCD camera for the detection of the speckle movement during heat propagation at the measurement location. Laser Speckle Photometry can be used for evaluating material properties, such as hardness and porosity. The approach is based on the estimation of the "Speckle Thermal Diffusivity" parameter K, that can be determined using the thermal diffusion equation and the modified correlation function from the pixel intensity of the speckle image variations during thermal activation. After testing, the correlation between parameter K and hardness, and porosity respectively, was found. Furthermore, mechanical material stress changes, also at elevated operating temperatures, can be estimated by the presented technique using the calculated parameter K. In this case, the thermal excitation will be partially replaced by mechanical activation, such as the tension process. The technique of LSP and the results of calibration experiments are presented in this paper.

Cikalova, Ulana; Nicolai, Juergen; Bendjus, Beatrice; Schreiber, Juergen

352

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

353

Polymeric passive laser shutters  

NASA Astrophysics Data System (ADS)

Passive laser shutters are designed to control laser pulse duration by the regulation of the Q-factor through the use of substances which change in transparency upon exposure to light. The present paper outlines the development of such a shutter composed of a radiation-resistant modified polymethyl methacrylic matrix which may be filled with different clear dyes. Experiments performed using a nickel dithiobenzyl complex as the dye are presented which show the optical density of the dye in the clear state to be proportional to the initial optical density of the shutter, and the ratio of these optical densities to depend on the purity of the materials and the extent of decay of the dye during polymerization. The feasibility of the polymer shutter in a small laser was demonstrated in experiments with a garnet laser, where no degradation was observed after 100,000 pulses, a neodymium glass laser operating for over 10,000 pulses, and a ruby laser. Potential applications of the modified polymethyl methacrylate material in other laser system components are also noted.

Gromov, D. A.; Diumaev, K. M.; Manenkov, A. A.; Masliukov, A. P.; Matiushin, G. A.; Nechitailo, V. S.; Prokhorov, A. M.

1982-10-01

354

Passive solar heating system  

NASA Astrophysics Data System (ADS)

The Toas State Office Building is a single-story office building in New Mexico which incorporates passive collection and storage of solar energy along with natural lighting for general illumination. The building is oriented to take advantage of early morning sunlight and is designed to supply 70% of the heating load by solar heat. The site is equipped with clerestory windows, totaling 2695 square feet, 296 square feet of south facing windows, and east and west window scoops totaling 218 square feet. The collected solar energy is stored in 14,080 gallons of water contained in drums located in the clerestory area, as well as in the masonry construction mass. Auxiliary heat is provided via electric strips in the supply ducts. Movable, insulated shutters are provided to reduce the loss from the clerestory window area at night. The project is described with pictures and diagrams of the final installation provided. An updated performance data report is included, and functional problems, general comments, maintenance and refurbishment recommendations are discussed.

Mingenbach, W.

1981-08-01

355

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

356

Passive blast pressure sensor  

DOEpatents

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

357

Sidewall passivation layer thickness and composition profiles of etched silicon patterns from angle resolved x-ray photoelectron spectroscopy analysis  

SciTech Connect

In this study, we present a technique to analyze side wall passivation layers formed on silicon sidewalls after plasma processing. The thickness and chemical composition are derived from angle resolved x-ray photoelectron spectroscopy analyses. It is a non-destructive, quasi in situ method to determine profiles of the thickness and the chemical composition of passivation layers in trenches up to an aspect ratio of about 3. The performance of this technique to quantify the passivation layer thickness is compared to a standard technique using secondary electron microscopy images with respect to two different samples and is found to be at least equivalent. The possible uncertainties and limitations of this technique are discussed as well.

Haass, Moritz; Darnon, Maxime; Joubert, Olivier [CNRS/UJF-Grenoble1/CEA LTM, 17 avenue des Martyrs, 38054 Grenoble cedex 9 (France)

2012-06-15

358

Passive IR SO2 Sensor.  

National Technical Information Service (NTIS)

A remote operating Passive Infrared SO2 Sensor was developed. A system of quantitative measurement for field operation was created with simplicity of operation and minimum of interference as objectives. The complexities of the radiative process limit accu...

J. M. Lepper

1967-01-01

359

Passivating metals on cracking catalysts  

Microsoft Academic Search

Metals such as nickel, vanadium and iron contaminating a cracking catalyst are passivated by contacting the cracking catalyst under elevated temperature conditions with antimony selenide, antimony sulfide, antimony sulfate, bismuth selenide, bismuth sulfide, or bismuth phosphate.

Mckay

1980-01-01

360

Passivating metals on cracking catalysts  

SciTech Connect

Metals such as nickel, vanadium and iron contaminating a cracking catalyst are passivated by contacting the cracking catalyst under elevated temperature conditions with antimony selenide, antimony sulfide, antimony sulfate, bismuth selenide, bismuth sulfide, or bismuth phosphate.

Mckay, D.L.

1980-01-15

361

Passive coherent location radar demonstration  

Microsoft Academic Search

This paper describes a passive coherent location (PCL) radar system developed by Dynetics, Inc. This system uses commercial FM broadcast signals for the radar waveform. This paper presents a technical description of the system and performance data.

C. L. Zoeller; M. J. Moody

2002-01-01

362

Psychoacoustics and Passive Sonar Detection.  

National Technical Information Service (NTIS)

A review is made of the statistical theory of signal detection, followed by application of signal detection theory to psychoacoustics. The differences between relatively simple laboratory tests and the complex problems of passive sonar operating in the re...

J. M. Stallard C. B. Leslie

1974-01-01

363

Active/Passive Optical Hydrography.  

National Technical Information Service (NTIS)

The Airborne Bathymetric Survey (ABS) concept was adopted by the Defense Mapping Agency and the Navy in 1985. The ABS system combines two independent sensors, an active lidar and a passive multispectral scanner using GPS satellite data for positioning, in...

M. C. Harris M. T. Kalcic S. C. Lingsch S. P. Haimbach

1990-01-01

364

Passive Nosetip Technology (PANT) Program.  

National Technical Information Service (NTIS)

A summary of the analytical and experimental activities performed on the Passive Nosetip Technology (PANT) program is given. The various test programs are identified and key test results are described. Analysis results in the areas of surface roughness ef...

M. R. Wool

1975-01-01

365

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

SciTech Connect

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

WILLS, C.E.

1999-07-12

366

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

Microsoft Academic Search

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

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

2009-01-01

367

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

368

Neutron-based measurements for nondestructive assay of minor actinides produced in nuclear power reactors  

Microsoft Academic Search

Because of their impacts on long-term storage of high-level radioactive waste and their value as nuclear fuels, measurement and accounting of the minor actinides produced in nuclear power reactors are becoming significant issues. This paper briefly reviews the commercial nuclear fuel cycle with emphasis on reprocessing plants and key measurement points therein. Neutron signatures and characteristics are compared and contrasted

J. E. Stewart; G. W. Eccleston; N. Ensslin; T. L. Cremers; L. A. Foster; H. O. Menlove; P. M. Rinard

1996-01-01

369

A rapid non-destructive assay to quantify soybean nodule gas permeability  

Microsoft Academic Search

The low gas permeability of a diffusion barrier in the cortex of soybean nodules plays a significant role in the protection\\u000a of nitrogenase from oxygen inactivation. It may also set an upper limit on nodule respiration and nitrogen fixation rates.\\u000a Two methods which have been used to quantify the gas permeability of leguminous nodules are reviewed and found to be

P. R. Weisz; T. R. Sinclair

1988-01-01

370

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

371

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

372

Passive and active closures by constraining mechanisms  

Microsoft Academic Search

This paper provides a unified theoretical framework for grasping and manipulation by robotic grippers and hands as well as for fixing works by fixtures and vises. The concept of passive closure and active closure for general constraining mechanisms is introduced. Passive closure is further classified into passive form closure and passive force closure. Conditions for these closures to hold are

Tsuneo Yoshikawa

1996-01-01

373

Nondestructive inspection and evaluation of composite-material flywheels  

SciTech Connect

It has been demonstrated that flywheels made from composite materials are capable of storing energy with a significantly higher energy density than those made from conventional metals. Since composite materials are also very durable and inherently safer for such applications, it would appear that they will play a major role in flywheel energy-storage systems. This report addresses the question of how flywheels made from composite materials can be inspected with nondestructive test methods to establish their initial quality and their subsequent integrity during service. A variety of methods is discussed in the context of special requirements for the examination of composite flywheel structures and the results of several example nondestructive evaluations before and after spin testing are presented. Recommendations for general nondestructive testing and evaluation of composite-material flywheels are made.

Reifsnider, K.L.; Boyd, D.M.; Kulkarni, S.V.

1982-02-24

374

Non-destructive evaluation and quality control of surface treatments  

NASA Astrophysics Data System (ADS)

The ability to detect and quantify beneficial surface and subsurface residual stresses, and operational damage in aerospace materials/structures in a reliable and efficient manner presents significant challenges to existing nondestructive inspection technologies. Induced Positron Analysis (IPA) has demonstrated the ability to nondestructively quantify shot peening/surface treatments and relaxation effects in single crystal superalloys, steels, titanium and aluminum with a single measurement as part of a National Science Foundation SBIR program and in projects with commercial companies. IPA measurement of surface treatment effects provides a demonstrated ability to quantitatively measure initial treatment effectiveness along with the effect of operationally induced changes over the life of the treated component. Use of IPA to nondestructively quantify surface and subsurface residual stresses in turbine engine materials and components has the potential to significantly improve the understanding at the microscale level the effects of surface coatings and treatments on the durability and fatigue life of critical components.

Rideout, Curtis A.; Ritchie, Scott J.

2007-03-01

375

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

376

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

377

Assay system to measure crate-size bulk transuranic waste  

Microsoft Academic Search

The Advanced Nuclear Technology Group of the Los Alamos National Laboratory recently designed and built a combined passive- and active-neutron assay system on which group members performed initial characterization measurements. The system is intended to provide sensitive assays at the 100-nCi\\/g level of both spontaneous fission and fissile transuranic isotopes in large crates of bulk waste. Such crates can be

E. R. Shunk; J. D. Atencio; H. F. Atwater; W. Bernard; J. M. Bieri; J. T. Caldwell; S. W. France; R. D. Hastings; G. C. Herrera; W. E. Kunz

1983-01-01

378

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

379

Practical applications of nondestructive evaluation for airport pavement analysis  

NASA Astrophysics Data System (ADS)

This paper discusses the equipment and methodologies currently used for nondestructive testing (NDT) and nondestructive evaluation (NDE) of the structural capacity of military and civil airport pavements, including: (1) commonly used equipment and test methods for measuring pavement response to dynamic loads; (2) qualitative and quantitative evaluation of NDT data; (3) methods for back-calculating layer properties from NDT data; (4) layered elastic methods for evaluating pavement performance using processed NDT data; and (5) application of analytical results for developing pavement rehabilitation and management strategies.

McQueen, Roy D.; Guo, Edward

1995-07-01

380

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

2004-12-08

381

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

2013-08-21

382

Mechanical Properties of Trabecular Bone by a Non-Destructive Compression Testing Approach  

Microsoft Academic Search

In order to optimize non-destructive mechanical testing of trabecular bone specimens, different techniques were analysed, and correlations were established between properties derived from such non-destructive testings and those derived from destructive testing. Non-destructive testing to a fixed percentage of predicted ultimate stress was hampered by inaccuracy of this prediction. Simulation of non-destructive testing conducted to the linear' part of the

Frank Linde; Charlotte Buch Gøosthgen; Ivan Hvid; Buntoeng Pongsoipetch; Søosren Bentzen

1988-01-01

383

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

SciTech Connect

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

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

1983-01-01

384

Use of calorimetric assay for operational and accountability measurements of pure plutonium metal  

SciTech Connect

Plutonium pure metal products (PMP) are high purity plutonium metal items produced by electrorefining. The plutonium metal is produced as an approximately 3-kg ring. Accountability measurements for the electro-refining runs are typically balance/weight factor (incoming impure metal), chemistry (pure metal rings), and calorimetric assay or neutron counting of the crucibles and other wastes. The PMP items are qualified for their end use by extensive chemical assay. After PMP materials are made they are often sent to the vault for storage before being sent to the casting process, the next step in the production chain. The chemical assay of PMP items often takes a few weeks; however, before the metal items are allowed into the vault they must be measured. Non-destructive assay personnel measure the metals either by multiplicity neutron counting or calorimetric assay, depending on which instrument is available, thus generating comparisons between non-destructive assay and chemical assay. The suite of measurements, calorimetric assay, chemical assay, and neutron mUltiplicity counting is compared for a large group of PMP items.

Cremers, Teresa L [Los Alamos National Laboratory; Sampson, Thomas E [Los Alamos National Laboratory

2010-01-01

385

Nondestructive Evaluation Quality Procedure: Personnel Qualification and Certification Radiographic Testing-Levels I& II  

SciTech Connect

This Operational Procedure establishes the minimum requirements for the qualification and certification/recertification of Nondestructive Evaluation (NDE) personnel in the nondestructive testing (NDT) radiographic testing (RT) method. This document is in accordance with the American Society for Nondestructive Testing Recommended Practice SNT-TC-1A, 1996, except as amended herein.

Dolan, K; Rikard, R D; Rodriquez, J

2003-07-01

386

46 CFR 38.25-3 - Nondestructive testing-TB/ALL.  

Code of Federal Regulations, 2010 CFR

...2009-10-01 2009-10-01 false Nondestructive testing-TB/ALL. 38.25-3 Section...and Inspections § 38.25-3 Nondestructive testingâTB/ALL. (a) Before nondestructive testing may be conducted to meet §...

2009-10-01

387

46 CFR 38.25-3 - Nondestructive testing-TB/ALL.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Nondestructive testing-TB/ALL. 38.25-3 Section...and Inspections § 38.25-3 Nondestructive testingâTB/ALL. (a) Before nondestructive testing may be conducted to meet §...

2012-10-01

388

46 CFR 38.25-3 - Nondestructive testing-TB/ALL.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Nondestructive testing-TB/ALL. 38.25-3 Section...and Inspections § 38.25-3 Nondestructive testingâTB/ALL. (a) Before nondestructive testing may be conducted to meet §...

2011-10-01

389

46 CFR 38.25-3 - Nondestructive testing-TB/ALL.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Nondestructive testing-TB/ALL. 38.25-3 Section...and Inspections § 38.25-3 Nondestructive testingâTB/ALL. (a) Before nondestructive testing may be conducted to meet §...

2010-10-01

390

Ultrasonic infrared thermal wave nondestructive evaluation for crack detection of several aerospace materials  

Microsoft Academic Search

The applications of ultrasonic infrared thermal wave nondestructive evaluation for crack detection of several materials, which often used in aviation alloy. For instance, steel and carbon fiber. It is difficult to test cracks interfacial or vertical with structure's surface by the traditional nondestructive testing methods. Ultrasonic infrared thermal wave nondestructive testing technology uses high-power and low-frequency ultrasonic as heat source

Weichao Xu; Jingling Shen; Cunlin Zhang; Ning Tao; Lichun Feng

2008-01-01

391

Surface passivation of Gallium Arsenide  

NASA Astrophysics Data System (ADS)

The surface passivation of Si doped (100) n-type gallium arsenide (GaAs) by chemical treatment with phosphoric acid (H3P04), phosphorus trichloride (PCl3), and sodium sulfide (Na2S.9H2O) was investigated using room temperature photoluminescence (PL) and a capacitance-voltage (C-V) and current-voltage (I-V) profiler. After passivation, the 300K PL increased for all three treatments. Best results obtained showed improvements of 1.4, 3.5 and 5.3 times greater of PL efficiency for H3PO4, PCl3 and Na2S, respectively, over unpassivated samples that were only cleaned and etched. Samples that were cleaned, etched and washed with de-ionized 18 Mohm, 5 ppm O2 content water showed about the same PL increase as the H3PO4 passivation. Capacitance-voltage and I-V profile curves showed the removal of the surface oxide hysteresis with the PCl3 passivated samples; however, re-oxidation seems to take longer than normal and to be confined to the passivation layer.

Racicot, Robert J.

1988-04-01

392

Passive resonators for wireless passive sensor readout enhancement  

NASA Astrophysics Data System (ADS)

A scheme to enhance a wireless passive sensor's readout is presented. This alternative consists of the addition of a passive inductive-capacitive resonator placed between the sensor and readout antenna. A discrete model is proposed and used in simulations to study the effects of the resonator in the sensor-antenna interaction. A resonator was fabricated at 28 MHz to test the enhancement of the sensor's signal. Increases in the sensor's signal and the power transmitted to the sensor were always obtained for frequencies below 28 MHz. All experimental results were consistent with the simulation outcomes.

Sanz, Diego A.; Mitrosbaras, Costantino; Unigarro, Edgar A.; Segura-Quijano, Fredy

2013-09-01

393

Clinical Assay Development Program (CADP)  

Cancer.gov

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

394

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

395

Nondestructive Evaluation of Oriented Strand Board Exposed to Decay Fungi  

Microsoft Academic Search

Stress wave nondestructive evaluation (NDE) technologies are being used in our laboratory to evaluate the performance properties of engineered wood. These techniques have proven useful in the inspection of timber structures to locate internal voids and decayed or deteriorated areas in large timbers. But no information exists concerning NDE and important properties of wood composites exposed to decay fungi. For

Barbara Illman; Vina W. Yang; Robert J. Ross; William J. Nelson

396

Expanding Tool for Nondestructive Inspection of Flexible Wire Rope.  

National Technical Information Service (NTIS)

The patent application relates to a tool for nondestructive testing of wire rope. Wire rope is held in position in a frame by two grips such as gripper pliers. One grip is rotated relative to the other thereby reverse-twisting and opening the rope strands...

J. L. Bachman J. M. Krafft

1976-01-01

397

Nondestructive measurement of refractive index profile for holey fiber preforms.  

PubMed

A non-destructive technique is presented to determine the refractive index profile of holey fiber preforms. The holes are filled with index matching oil and the holey preform deflection data is measured. An improved optical path-length formula and back projection method is used to reconstruct the two-dimensional filled holey fiber preform refractive index distribution. PMID:19471359

Zhao, Yucheng; Lyytikainen, Katja; van Eijkelenborg, Martijn; Fleming, Simon

2003-10-01

398

Application of nondestructive evaluation techniques on concrete dams  

Microsoft Academic Search

Many mining and civil engineering structures are showing signs of deterioration due to various factors. In recent years, the heavy cost of repairs of concrete infrastructures has been reduced by using nondestructive evaluation (NDE) techniques to pinpoint problem areas. This paper presents the theoretical and practical aspects of the Miniature Seismic Reflection (MSR) system for the evaluation of concrete dams.

F. P. Hassani; P. Guevremont; M. Momayez; A. Sadri; K. Saleh

1997-01-01

399

Multispectral fluorescence imaging techniques for nondestructive food safety inspection  

Microsoft Academic Search

The use of spectral sensing has gained acceptance as a rapid means for nondestructive inspection of postharvest food produce. Current technologies generally use color or a single wavelength camera technology. The applicability and sensitivity of these techniques can be expanded through the use of multiple wavelengths. Reflectance in the Vis\\/NIR is the prevalent spectral technique. Fluorescence, compared to reflectance, is

Moon S. Kim; Alan M. Lefcourt; Yud-Ren Chen

2004-01-01

400

Proceedings of the Workshop on Structural Composites and Nondestructive Evaluation.  

National Technical Information Service (NTIS)

The problems and opportunities in the nondestructive evaluation of composites are covered in formal papers and a summary of the discussion which took place at a Workshop held in Dayton on February 13-14, 1974. The recommendations arrived at by an National...

1974-01-01

401

Photocurrent estimation from multiple nondestructive samples in CMOS image sensor  

Microsoft Academic Search

CMOS image sensors generally suffer form lower dynamic range than CCDs due to their higher readout noise. Their high speed readout capability and the potential of integrating memory and signal processing with the sensor on the same chip, open up many possibilities for enhancing their dynamic range. Earlier work have demonstrated the use of multiple non-destructive samples to enhance dynamic

Xinqiao Liu; Abbas El Gamal

2001-01-01

402

Overview of Mathematical Modeling in Nondestructive Evaluation (NDE)  

Microsoft Academic Search

This report presents a broad overview of mathematical modeling in nondestructive evaluation (NDE). The primary emphasis is to expand the review of NDE modeling literature covered by previous general works. To provide a starting point for researchers and engineers, the discussions and references include multiple modeling approaches (analytical, asymptotic, and numerical) for a variety of NDE techniques. A second emphasis

John C. Aldrin

2002-01-01

403

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

404

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

405

Nondestructive evaluation of concrete dams and other structures  

Microsoft Academic Search

This paper presents an overview of several stress-wave based nondestructive testing methods which can be used to assess the condition of concrete structures such as dams, buildings, and foundations. The specific methods to be presented include the use of the impact echo (IE) and spectral analysis of surface waves (SASW) methods in the assessment of dam concrete condition (including freeze-thaw

Larry D. Olson; Dennis A. Sack

1995-01-01

406

DEVELOPMENT OF NONDESTRUCTIVE CHARACTERIZATION TECHNOLOGIES FOR PROCESS CONTROL OF CERAMICS  

Microsoft Academic Search

Ceramic matrix composites using either continuous ceramic fibers or ceramic whiskers have been shown to have significantly higher fracture toughness than monolithic ceramics. High fracture toughness is necessary for ceramic applications in many advanced heat engines. However, in wear applications such as bearings (ball and roller), or in certain corrosive environments, monolithic ceramics have a significant role. Nondestructive characterization methods

W. A. ELLINGSON; N. GOPALSAMI; S. L. DIECKMAN; T. LUETHI

1992-01-01

407

Condensed matter physics for non-destructive 100 T magnets  

Microsoft Academic Search

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

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

1998-01-01

408

SAW Electromagnetic Transducer Design for Nondestructive Evaluation Applications  

Microsoft Academic Search

Abxrroct-Recent progress in surface acoustic wave (SAW) electromagnetic transducer (EMT) modeling and fabrication techniques have greatly increased EMT versatility for nondestructive evaluation (NDE) applications. Unlike other types of SAW NDE transducers that suffer from variability in manufacture and coupling conditions, virtually identical EMT's can be made that have predictable characteristics. Information is presented for straightforward design on different materials, including

T. L. Szabo; H. M. Frost

1976-01-01

409

Novel quantitative non-destructive testing method for composite structures  

Microsoft Academic Search

A novel QNDT (quantitative non-destructive testing) method is developed that is combined with a phase-shifting shearing speckle and thermograph, and, it aims at the detection of faults such as cracks, voids, delamination and weak areas. The technique is immune to ambient noise and is suitable for measuring the in situ environment. Some different depth defects that would produce deformation differing

Jin-long Chen; Yu-wen Qin; Hong-wei Ji; Xin-hua Ji

1998-01-01

410

NON-DESTRUCTIVE TESTING OF THE SANCTUARY OF VICOFORTE  

Microsoft Academic Search

A series of non-destructive tests such as Radiation Thermometer, Electromagnetic Radar, Impact Echo Scanner, Concrete Test Hammer, Scratch Tester, Windsor Pin System, and Electromagnetic Induction Scanner are carried out for diagnostic inspection of deterioration on the Sanctuary of Vicoforte. In this paper, 1) Delamination of stone finishing and fresco painting, 2) Thickness of main dome and vaults above chapels, 3)

T. Aoki; T. Komiyama; Y. Tanigawa; S. Hatanaka; N. Yuasa; H. Hamasaki; M. A. Chiorino; R. Roccati

411

Backscattering grain noise modelling in ultrasonic non-destructive testing  

Microsoft Academic Search

Many materials present an internal grain microstructure. When these materials are subjected to ultrasonic non-destructive testing, the grains behave like scattering centres producing unwanted backscattered noise that can make the detection of true defects difficult. This paper is devoted to the modelling of the probability density and the spacetime correlation functions of the grain noise complex envelope. Assuming statistical independence

Luis Vergara-Dominguez; J. Manuel Paez-Borrallo

1991-01-01

412

The membrane resonance method of non-destructive testing  

Microsoft Academic Search

The physical basis of the membrane resonance method of non-destructive testing has been investigated both theoretically and experimentally. The method involves exciting the structure and monitoring the response at the same point, and can be used to detect the presence of delaminations or disbonds at that location. Its advantage over ultrasonic testing is that no couplant is required between the

P. Cawley; C. Theodorakopoulos

1989-01-01

413

IGBT RBSOA non-destructive testing methods: Analysis and discussion  

Microsoft Academic Search

The investigation about RBSOA limits and the study of the instabilities in high power IGBT devices, during clamped and unclamped operations can be executed by means of non-destructive experimental test circuits where the power device is switched in the presence of a protection circuit able to save it in the case of a dangerous condition to take place. This work,

Carmine Abbate; Giovanni Busatto; Francesco Iannuzzo

2010-01-01

414

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

415

NON-DESTRUCTIVE TESTING OF FUEL ELEMENTS FOR NUCLEAR REACTORS  

Microsoft Academic Search

It is possible to mark out two scopes of non-destructive testing which are most important and specific to nuclear power. • The testing of nuclear fuel elements (NFE) and nuclear fuel assemblies (NFA) in process of their production; • Material engineering researches of NFE and NFA before and after their using in reactor. Significant growth of NFE and NFA production

N. R. Kuzelev

416

NON-DESTRUCTIVE DETECTION OF PITS IN DRIED PLUMS  

Microsoft Academic Search

An economical, non-destructive device was constructed to detect pits in dried plums (prunes). The device compresses the product between a roller and a force transducer, which detects the higher force generated when a pit is present. Two methods of classifying fruit were developed, one based on the maximum magnitude of the compression force and the other on analysis of the

R. P. Haff; E. S. Jackson; T. C. Pearson

417

LATEST METHODS OF NON-DESTRUCTIVE TESTING OF RAILWAY VEHICLES  

Microsoft Academic Search

Non-destructive methods are making a fast progress due to extensive scientific treatment and practical applications of new testing techniques. The application of individual techniques requires of their users good knowledge of the relevant theory and a lot of experience. The experience is the main guideline in choosing the right testing technique. The paper focuses on the ultrasonic testing methods developed

V. Jemec; J. Grum

418

Some examples of nondestructive flaw detection by shearography  

Microsoft Academic Search

This paper presents some examples of nondestructive flaw detection using an optical method based on speckle shearing interferometry called shearography. In the method, a structure under study is illuminated by laser and imaged by a special image-shearing camera. After suitable processing, a fringe pattern which represents loci of surface displacement derivatives, i.e., strains, is observed in the image. Since defects

F. S. Chau; S. L. Toh; C. J. Tay; H. M. Shang

1989-01-01

419

Nondestructive firmness sensing using a laser air-puff detector  

Microsoft Academic Search

Recent studies indicate that peaches harvested at the right maturity stage are preferred by consumers. Reliable means of assessing peach maturity will increase efficiency and reduce costs. Current methods for determining harvest maturity of peaches are either subjective or destructive and are inherently inconsistent and wasteful. Nondestructive and objective methods for maturity sensing are needed. A laser air-puff firmness detector

Y.-C Hung; S. E Prussia; G. O. I Ezeike

1999-01-01

420

An Instructional Program for Training Nondestructive Testing and Inspection Technicians.  

ERIC Educational Resources Information Center

|This document, the second portion of a two-part study, is designed to provide a guide for the formal training of technicians for nondestructive testing and inspection. Information in the guide is based on results of the industrial survey discussed in Part I. The subject matter is intended to be both flexible and comprehensive, and instructional…

Stokes, Vernon L.

421

Condensed matter physics for non-destructive 100 T magnets  

NASA Astrophysics Data System (ADS)

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

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

1998-05-01

422

Improving nondestructive testing probe performance by digital processing techniques  

Microsoft Academic Search

This paper proposes a novel probe for nondestructive testing (NDT) based on eddy currents. The novelty of the probe is in the digital processing algorithms used to extract field information from rough voltage data. The digital signal processing algorithm as well as the working parameters of the NDT probe were experimentally optimized looking for the best compromise between sensitivity and

Andrea Bernieri; Giovanni Betta; Luigi Ferrigno

2003-01-01

423

Modeling and construction of new detector for nondestructive magnetic testing  

NASA Astrophysics Data System (ADS)

The paper is oriented on modelling, construction and testing of new design of magnetic defectoscope for nondestructive inspection of pipes. This defectoscope is determined for protection of tube in steam generator of electric power station. This approach allows shifting the accuracy limit to be better than 0.3% for internal and external defects.

Lesnak, Michal; Pistora, Jaromir

2004-04-01

424

Multiattribute Bayesian Acceptance Sampling Plans Under Nondestructive Inspection  

Microsoft Academic Search

A methodology for determining optimal sampling plans for Bayesian multiattribute acceptance sampling models is developed. Inspections are assumed to be nondestructive and attributes are classified as scrappable or screenable according to the corrective action required when a lot is rejected on a given attribute. The effects of interactions among attributes on the resulting optimal sampling plan are examined and show

Kwei Tang; Robert Plante; Herbert Moskowitz

1986-01-01

425

Wideband Microwave Imaging of Concrete for Nondestructive Testing  

Microsoft Academic Search

Radar has the potential of becoming a powerful and effective tool for the nondestructive testing of concrete structures. An advancement of the method can be achieved through the understanding of the inter- action between electromagnetic waves and concrete, and the identification of optimum radar measurement pa- rameters for probing concrete. For the determination of optimum parameters, systematic radar measurements are

Hong C. Rhim; Oral Bu?yu?ko?ztu?rk

2000-01-01

426

FORENSIC EXAMINATION USING A NONDESTRUCTIVE EVALUATION METHOD FOR SURFACE METROLOGY  

Microsoft Academic Search

The objective of this paper is to describe the use of a new technique of optical profilometry in a nondestructive, non-contact fashion for the comparison of two metallic surfaces, one hard and one soft. When brought in contact with one another, the harder material (i.e. the tool) will impress its surface roughness onto the softer. It is understood that the

David J. Eisenmann; L. Scott Chumbley

2009-01-01

427

Forensic Examination Using a Nondestructive Evaluation Method for Surface Metrology  

Microsoft Academic Search

The objective of this paper is to describe the use of a new technique of optical profilometry in a nondestructive, non-contact fashion for the comparison of two metallic surfaces, one hard and one soft. When brought in contact with one another, the harder material (i.e. the tool) will impress its surface roughness onto the softer. It is understood that the

David J. Eisenmann; L. Scott Chumbley

2009-01-01

428

A focused-field eddy current sensor for nondestructive testing  

Microsoft Academic Search

An original structure of an eddy current sensor meant for nondestructive testing of electrically conducting materials is presented. The basic physical principles of the sensors are recalled, and the fact that it is generally impossible to design a sensor with good spatial resolution and good range detection is discussed. An original idea is proposed, which consists of exploiting the good

Dominique Placko; Isabelle Dufour

1993-01-01

429

Pulsed eddy-current nondestructive testing of ferromagnetic tubes  

Microsoft Academic Search

In sinusoidal eddy-current (EC) nondestructive testing (NDT) of thick ferromagnetic tubes, such as oil-well casings, average wall thickness is measured with an exciter coil and a detector coil displaced by more than two tube diameters [remote field eddy current (RFEC) technique]. Since RFEC cannot differentiate outer from inner defects, the average tube inner diameter is determined at higher frequency with

Darko Vasic; Vedran Bilas; Davorin Ambrus

2004-01-01

430

Genetic algorithms for nondestructive testing in crack identification  

Microsoft Academic Search

A method to identify the nature of a crack on the surface of a region using nondestructive testing (NDT) and inverse problem methodology is presented. A genetic algorithm (GA) based approach, which involves a global search to avoid local minima, is presented and applied to solve the inverse problem of identifying the position, shape and the orientation of a surface

A. A. Arkadan; T. Sareen; S. Subramaniam

1994-01-01

431

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

432

Blind deconvolution of ultrasonic signals in nondestructive testing applications  

Microsoft Academic Search

Advanced nondestructive testing techniques use a laser to generate ultrasonic waves at the surface of a test material. An air-coupled transducer receives the ultrasound that is the convolution of the signal leaving the test material and the distortion function. Blind deconvolution methods are applied to estimate the signal leaving the material

A. K. Nandi; D. Mampel; B. Roscher

1997-01-01

433

Fuzzy logic in nondestructive testing of aerospace structures  

Microsoft Academic Search

In nondestructive testing, to locate the faults, we send an ultrasonic signal and measure the resulting vibration at different points. To describe and combine the uncertainty corresponding to different measurements and fuzzy estimates, we used fuzzy logic. As a result, we get reasonably simple computational models which lead to as good fault detection as the known more complicated models

Murali Krishna; Vladik Kreinovich; Roberto Osegueda

1999-01-01

434

Nondestructive testing method of concrete using impact acoustics  

Microsoft Academic Search

A new nondestructive testing method for concrete using impact acoustics is investigated. Impact acoustics, which has a strong relation with the vibration of a concrete surface, can offer important information about the physical properties of concrete structures such as shapes, material properties and defects. In this paper, the relation between impact acoustics and vibration at the same surface of the

Y. Ito; T. Uomoto

1997-01-01

435

A measurement system based on magnetic sensors for nondestructive testing  

Microsoft Academic Search

The paper deals with a measurement system based on a low-cost eddy current probe for nondestructive testing (NDT) on conducting materials aimed at reconstructing the shape and position of thin cracks. The magnetic probe is characterized, highlighting good repeatability, linearity, and overall accuracy. A number of different measurement approaches are investigated, in order to choose the most appropriate for NDT

Andrea Bernieri; Giovanni Betta; Guglielmo Rubinacci; Fabio Villone

2000-01-01

436

Time reversal techniques in ultrasonic nondestructive testing of scattering media  

Microsoft Academic Search

Time reversal techniques are adaptive methods that can be used in nondestructive evaluation to improve flaw detection through inhomogeneous and scattering media. Two techniques are presented: the iterative time reversal process and the DORT (French acronym for decomposition of the time reversal operator) method. In pulse echo mode, iterative time reversal mirrors allow one to accurately control wave propagation and

Claire Prada; Estelle Kerbrat; Didier Cassereau; Mathias Fink

2002-01-01

437

Disposable PVDF ultrasonic transducers for nondestructive testing applications  

Microsoft Academic Search

Disposable ultrasonic contact transducers have been constructed with inexpensive PVDF films for nondestructive testing (NDT) applications. This paper reports the temperature-dependent ultrasonic performance of commercial polyvinylidene fluoride (PVDF) films and PVDF sensors. PVDF film was evaluated for its material properties of interest for ultrasonic transducer performance including the relative dielectric constant εr, dielectric loss tangent tan ?e , electromechanical coupling

Lewis F. Brown; J. L. Mason

1996-01-01

438

Integrated low-temperature superconductor SQUID gradiometers for nondestructive evaluation  

Microsoft Academic Search

We describe an eddy current nondestructive evaluation system using a low-temperature superconductor magnetic field sensor in an electromagnetically unshielded environment. The sensor comprises a niobium dc superconducting quantum interference device (SQUID) integrated with a first-order gradiometric pickup coil to reject spatially uniform interference fields but remain sensitive to flaw induced fields. We demonstrate its use in locating and mapping subsurface

Uho Klein; Morag E. Walker; Chris Carr; D. M. McKirdy; C. M. Pegrum; G. B. Donaldson; A. Cochran; H. Nakane

1997-01-01

439

Optical nondestructive evaluation technique capable of predicting failure  

NASA Astrophysics Data System (ADS)

An optical interferometric nondestructive evaluation technique is introduced. Based on electronic speckle-pattern interferometry and a recent theory of plastic deformation, this technique is capable of visualizing stress concentration and predicting the location and timing of the failure of the object. The operation of the technique is demonstrated for tensile analyses of aluminum alloy samples.

Yoshida, Sanichiro J.; Pardede, M. H.; Siahaan, B.; Pardede, M.; Muhamad, I.; Sijabat, N.; Simangunsong, H.; Simbolon, T.; Adlin; Jubir; Kusnowo, A.

1999-02-01

440

Lockin-interferometric imaging of thermal waves for nondestructive testing  

Microsoft Academic Search

Phase shifting shearography monitors the mechanical behaviour of an object under load, which makes it a valuable tool for non-destructive testing. However, it cannot determine the depth of defects, and sometimes, the gradient of the displacement of the whole object is so large that it hides small deviations caused by flaws. Our approach to overcome these limitations is based on

Philipp Menner; Gerd Busse

2011-01-01

441

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

442

Nondestructive Evaluation of Metal Fatigue Using Nonlinear Acoustics  

Microsoft Academic Search

Safe-life and damage-tolerant design philosophies of high performance structures have driven the development of various methods to evaluate nondestructively the accumulation of damage in such structures resulting from cyclic loading. Although many techniques have proven useful, none has been able to provide an unambiguous, quantitative assessment of damage accumulation at each stage of fatigue from the virgin state to fracture.

John H. Cantrell

2009-01-01

443

NONDESTRUCTIVE EVALUATION OF METAL FATIGUE USING NONLINEAR ACOUSTICS  

Microsoft Academic Search

Safe-life and damage-tolerant design philosophies of high performance structures have driven the development of various methods to evaluate nondestructively the accumulation of damage in such structures resulting from cyclic loading. Although many techniques have proven useful, none has been able to provide an unambiguous, quantitative assessment of damage accumulation at each stage of fatigue from the virgin state to fracture.

John H. Cantrell

2009-01-01

444

Passive-solar retrofit concepts  

NASA Astrophysics Data System (ADS)

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

1981-09-01

445

Passive solar study. Existing passive solar contributions in buildings.  

National Technical Information Service (NTIS)

In November 1992 the Energy Technology Support Unit invited ECD to prepare a study with the objective of quantifying the passive solar contribution to the UK domestic and non-domestic building energy requirements at 1990 levels. This has been achieved by ...

S. Burton J. Maxwell

1993-01-01

446

Infrared thermal wave nondestructive testing for rotor blades in wind turbine generators non-destructive evaluation and damage monitoring  

Microsoft Academic Search

The rotor blades are key components in wind turbine generators. A visual inspection of the laminated shells for delaminations, air pockets, missing\\/disoriented fabric etc. is in most cases also not possible due to the manufacturing process, so Non-destructive testing and evaluation (NDT & E) techniques for assessing the integrity of rotor blades structure are essential to both reduce manufacturing costs

Shi Bin Zhao; Cun-Lin Zhang; Nai-Ming Wu; Yu-Xia Duan; Hao Li

2009-01-01

447

Surface Passivation of Gallium Arsenide.  

National Technical Information Service (NTIS)

The surface passivation of Si doped (100) n-type gallium arsenide (GaAs) by chemical treatment with phosphoric acid (H3P04), phosphorus trichloride (PCl3), and sodium sulfide (Na2S.9H2O) was investigated using room temperature photoluminescence (PL) and a...

R. J. Racicot

1988-01-01

448

MGA and passive neutron measurements.  

National Technical Information Service (NTIS)

MGA is a gamma-ray spectrum analysis program for determining relative plutonium isotopic abundances. The isotopic composition of a plutonium sample is needed to calculate (sup 240)Pu(sub eff) that is used to interpret passive neutron coincidence measureme...

W. D. Ruhter R. Gunnink S. Baumann S. Abeynaike J. Verplancke

1993-01-01

449

Passive energy in historical Tunisia  

Microsoft Academic Search

The Romans of 200 AD used a variety pf passive energy devices for climate control of underground housing in the ancient city of Bulla Regia, Tunisia. The preliminary results of a study of three such homes are reported and several of the climate control devices and the methods used to create an even level of natural daylighting in their underground

R. S. Cole; R. Kennedy

1980-01-01

450

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

451

Slow Modes in Passive Advection.  

National Technical Information Service (NTIS)

The anomalous scaling in the Kraichnan model of advection of the passive scalar by a random velocity field with non-smooth spatial behavior is traced down to the presence of slow resonance-type collective modes of the stochastic evolution of fluid traject...

D. Bernard K. Gawedzki A. Kupiainen

1997-01-01

452

Passive solar energy in buildings  

Microsoft Academic Search

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

1988-01-01

453

A Multiband Passive Radar Demonstrator  

Microsoft Academic Search

Passive radar systems that exploit signals from the plethora of RF emissions that exist in the external environment offer a number of advantages over conventional active radar system, including procurement and operational cost saving. Each emitter has its own characteristics, including waveforms, which dictate system performance. BAE Systems Advanced Technology Centre has designed and built a demonstrator system to act

Dale Gould; Robert Pollard; Carlos Sarno; Paul Tittensor

2006-01-01

454

PASSIVE DETECTION OF VEHICLE LOADING  

Microsoft Academic Search

The Digital Imaging and Remote Sensing Laboratory (DIRS) at the Rochester Institute of Technology, along with the Savannah River National Laboratory is investigating passive methods to quantify vehicle loading. The research described in this paper investigates multiple vehicle indicators including brake temperature, tire temperature, engine temperature, acceleration and deceleration rates, engine acoustics, suspension response, tire deformation and vibrational response. Our

2012-01-01

455

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

456

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

457

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

SciTech Connect

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

GOLDBERG, H.J.

1999-05-12

458

Passively walking five-link robot  

Microsoft Academic Search

In this article we investigate the dynamics of a five-link, passive bipedal robot. The passivity in this context stands for the ability of the robot to walk autonomously down an inclined surface without any external source of energy. Previous research efforts in passive walking were limited to four link models with knees or 2-link models without knees with a variety

Elena Borzova; Yildirim Hurmuzlu

2004-01-01

459

Radiometric linearity in passive FTIR spectrometry  

Microsoft Academic Search

Passive standoff FTIR spectrometry relies on the radiance differential between a background scene and a target vapor analyte. Unlike traditional FTIR approaches controlling radiance levels within a narrow range, the passive configuration often encounters a large variance in radiance levels. This places higher demands on the passive FTIR configuration for maintaining linearity. The present study assesses the radiometric linearity of

Robert T. Kroutil; Roger J. Combs; Robert B. Knapp

1999-01-01

460

User evaluation study of passive solar residences  

SciTech Connect

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

Towle, S.

1980-03-01

461

Phase-change products for passive homes  

SciTech Connect

The use of phase change materials (PCM) in passive solar energy applications is discussed. The performance of the passive phase change storage house designs compared with the annual heating loads for an identical house having no added thermal storage mass is discussed. The use of calcium chloride hexahydrate as the PCM in several passive solar applications is discussed.

Kohler, J.; Lewis, D.

1983-05-01

462

Treat mine water using passive methods  

Microsoft Academic Search

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

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

1993-01-01

463

Passive smoking and risk of coronary heart disease and stroke: prospective study with cotinine measurement  

Microsoft Academic Search

Objective To examine the associations between a biomarker of overall passive exposure to tobacco smoke (serum cotinine concentration) and risk of coronary heart disease and stroke. Design Prospective population based study in general practice (the British regional heart study). Participants 4729 men in 18 towns who provided baseline blood samples (for cotinine assay) and a detailed smoking history in 1978-80.

Peter H Whincup; Julie A Gilg; Jonathan R Emberson; Martin J Jarvis; Colin Feyerabend; Andrew Bryant; Mary Walker; Derek G Cook

2004-01-01

464

Fundamental studies of passivity and passivity breakdown. Final report, [September 1993--September 1994  

SciTech Connect

Purpose is to understand the mechanisms for growth and breakdown of passive films on metal and alloy surfaces in aqueous medium; a secondary goal is to devise methods for predicting localized corrosion damage in industrial systems. Tasks currently being studied are: formation of bilayer structures in passive films on metals and alloys; passivity breakdown on solid vs. liquid gallium; roles of alloying elements in passivity breakdown; electrochemical impedance spectroscopy of passive films; electronic structure of passive oxide films; photoelectrochemical impedance spectroscopy of passive films; and kinetics of localized attack.

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

1994-02-21

465

Non-destructive NIR FT Raman analysis of plants  

NASA Astrophysics Data System (ADS)

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

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

1999-10-01

466

Nondestructive damage evaluation in ceramic matrix composites for aerospace applications.  

PubMed

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

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

2013-07-11

467

Nondestructive characterization of as-fabricated composite ceramic panels  

SciTech Connect

Decreasing the weight of protective systems, while minimizing the decrease in ballistic performance, is an ongoing goal of the Army. Ceramic materials are currently combined with other materials in these types of structures in order to decrease weight without losing ballistic performance. This includes structures in which the ceramic material is confined in some way and in which the ceramic material is completely encapsulated. Confinement or encapsulation of ceramic material within a structure generally adds complexity and cost. Relatively simple panel specimens fabricated with ceramic tiles on aluminum backings and side confinement using steel were evaluated using nondestructive methods, including x-ray comput