bluuebunny/crossref_metadata_2025 huggingface dataset:
Does Obesity Really Make the Femur Stronger? BMD, Geometry, and Fracture Incidence in the Women's Health Initiative-Observational Study
Authors: Beck Thomas J , Petit Moira A , Wu Guanglin , LeBoff Meryl S , Cauley Jane A , Chen Zhao
Published: March 2009

Heavier individuals have higher hip BMD and more robust femur geometry, but it is unclear whether values vary in proportion with body weight in obesity. We studied the variation of hip BMD and geometry across categories of body mass index (BMI) in a subset of postmenopausal non-Hispanic whites (NHWs) from the Women's Health Initiative Observational Cohort (WHI-OS). The implications on fracture incidence were studied among NHWs in the entire WHI-OS. Baseline DXA scans of hip and total body from 4642 NHW women were divided into BMI (kg/m2) categories: underweight (<18.5), healthy weight (18.5–24.9), overweight (25–29.9), and mild (30–34.9), moderate (35–39.9), and extreme obesity (>40). Femur BMD and indices of bone axial (cross-sectional area [CSA]) and bending strength (section modulus [SM]) were extracted from DXA scans using the hip structure analysis (HSA) method and compared among BMI categories after adjustment for height, age, hormone use, diabetes, activity level, femur neck-shaft angle, and neck length. The association between BMI and incident fracture was studied in 78,013 NHWs from the entire WHI-OS over 8.5 ± 2.6 (SD) yr of follow-up. Fracture incidence (cases/1000 person-years) was compared among BMI categories for hip alone, central body (hip, pelvis, spine, ribs, and shoulder girdle), upper extremity (humerus and distal), and lower extremity (femur shaft and distal but not hip). Femur BMD, CSA, and SM were larger in women with higher BMI, but values scaled in proportion to lean and not to fat or total body mass. Women with highest BMI reported more falls in the 12 mo before enrollment, more prevalent fractures, and had lower measures of physical activity and function. Incidence of hip fractures and all central body fractures declined with BMI. Lower extremity fractures distal to the hip trended upward, and upper extremity incidence was independent of BMI. BMD, CSA, and SM vary in proportion to total body lean mass, supporting the view that bones adapt to prevalent muscle loads. Because lean mass is a progressively smaller fraction of total mass in obesity, femur BMD, CSA, and SM decline relative to body weight in higher BMI categories. Traumatic forces increase with body weight, but fracture rates at the hip and central body were less frequent with increasing BMI, possibly because of greater soft tissue padding. There was no evident protective effect in fracture rates at less padded distal extremity sites. Upper extremity fractures showed no variation with BMI, and lower extremity fracture rates were higher only in the overweight (BMI = 25–29.9 kg/m2).
Intralobular Pulmonary Lymphatic Distribution in Normal Human Lung Using D2-40 Antipodoplanin Immunostaining
Authors: Kambouchner Marianne , Bernaudin Jean-François
Published: March 2009

It has been assumed for a long time that except for limited areas close to respiratory bronchioles or their satellite arteries, there is no evidence of lymphatic vessels deep in the pulmonary lobule. An immunohistochemical study using the D2-40 monoclonal antibody was performed on normal pulmonary samples obtained from surgical specimens, with particular attention to the intralobular distribution of lymphatic vessels. This study demonstrated the presence of lymphatics not only in the connective tissue surrounding the respiratory bronchioles but also associated with intralobular arterioles and/or small veins even less than 50 μm in diameter. A few interlobular lymphatic vessels with a diameter ranging from 10 μm to 20 μm were also observed further away, in interalveolar walls. In conclusion, this study, using the D2-40 monoclonal antibody, demonstrated the presence of small lymphatic channels within the normal human pulmonary lobules, emerging from interalveolar interstitium, and around small blood vessels constituting the paraalveolar lymphatics. This thin intralobular lymphatic network may play a key pathophysiological role in a wide variety of alveolar and interstitial lung diseases and requires further investigation. (J Histochem Cytochem 57:643–648, 2009)
Financial Reporting for Private Companies: The Canadian Experience*
Authors: Rennie Morina D. , Senkow David W.
Published: March 2009

The issue of whether small and/or private companies should be allowed to use simplified accounting standards in financial reports has concerned the accounting profession for decades. It has been argued that preparing financial reports in accordance with the large volume of promulgated standards contained in generally accepted accounting principles (GAAP), some of which are relatively complex, has put a significant strain on the resources of small/private business. Moreover, information produced and presented in accordance with at least some accounting standards within GAAP may not be relevant for the users of small/private companies' financial statements.

In this paper we look at differential reporting in Canadian GAAP, which gives nonpublicly accountable enterprises the ability to opt out of certain CICA Handbook requirements with unanimous consent of the shareholders. We look at lobbying activity in response to the proposed differential reporting standard and at nonpublicly accountable company experience with the differential reporting opportunity in the period since the standard was promulgated.
Glossar Verkehrsflugzeuge (DE–EN) (1. Teil)
Authors: Weilandt Annette
Published: March 2009

Der europäische Konzern Airbus Industries hat erstmals mehr Flugzeuge verkauft als der amerikanische Konkurrent Boeing, und der Flugverkehr nimmt, nicht zuletzt durch die sog. Billigflieger, weiter zu. Ob dies einhergeht mit einem zunehmenden Translationsbedarf im Bereich Flugzeugbau wäre interessant zu wissen; in jedem Fall ist es für Übersetzer und Dolmetscher interessant, zumindest die Grundbegriffe und Benennungen der Verkehrsflugzeuge zu kennen. Das folgende Glossar stammt aus dem dritten Hauptteil der Diplomarbeit „Verkehrsflugzeuge. Eine terminologische Untersuchung im Deutschen und Englischen“, die am 20.10.2003 am Institut für Angewandte Linguistik und Translatologie (IALT) der Universität Leipzig eingereicht wurde. Das mit CATS erstellte Glossar enthält 848 Datensätze mit 346 Begriffen, 587 dt. und 616 engl. Benennungen sowie deutschen und englischen Definitionen nahezu aller Begriffe; im Folgenden drucken wir die Richtung deutsch-englisch.
Endovascular Brachytherapy. A Concise English-German Glossary of Terms, Abbreviations, and Acronyms
Authors: Köppen Ulrich , Kirisits Christian
Published: March 2009

Brachytherapy has been established worldwide as outstanding radiotherapeutic modality in the treatment of certain coronary and peripheral artery conditions and has initially been focused on in English language publications. Any new form of interdisciplinary medical treatment poses terminological problems and uncertainties. The following bilingual glossary aims at cardiologists, radiotherapists, medical physicists, and also at translators and interpreters. It attempts to clarify the most frequent nomenclature questions and pitfalls in the wake of endovascular brachytherapy. Terms, abbreviations and acronyms of daily use in one discipline may not belong to the terminological routine in the other and have therefore been included by intention. It goes without saying that any compilation of this kind is bound to fall short of completeness.
Das übersetzungsdidaktische Potential der konstrastiven Grammatik
Authors: Königs Karin
Published: March 2009

Das didaktische Potential der kontrastiven Grammatik – die Chance, Studierenden strukturiertes Wissen zu Transfermöglichkeiten zu vermitteln – wird in der Übersetzerausbildung kaum genutzt. Wie übersetzungsrelevante kontrastiv-grammatische Kenntnisse konkret aussehen können, wird an fünf systembedingten Problembereichen der englisch-deutschen Übersetzung demonstriert. Anschließend wird erläutert, warum ein kontrastiv-grammatischer Ansatz auch heute kein Anachronismus ist, sondern vielmehr elementarer Bestandteil des Curriculums sein sollte.
Fachwortliste Damenoberbekleidung (EN–DE)
Authors: Hoy Nicole
Published: March 2009

Dieses auf den ersten Blick so alltägliche Fachgebiet hat bei näherer Betrachtung seine Tücken – oder wer kennt schon den Unterschied zwischen Flügel-, Fledermaus- oder Trompetenärmeln, ganz zu schweigen von offenem Kragen, Auslegekragen, Spaten- und Wimpelkragen? Das Glossar zu diesem Thema stammt aus der Diplomarbeit „Damenoberbekleidung. Eine terminologische Untersuchung im Deutschen und Englischen“, die am 12. April 2005 am Institut für Angewandte Linguistik und Translatologie (IALT) der Universität Leipzig eingereicht wurde. Es wurde mit CATS erstellt und enthält 945 Datensätze mit 706 deutschen und 793 englischen Benennungen zu 554 Begriffen, sowie die deutschen und englischen Definitionen nahezu aller Begriffe. Die folgende Fachwortliste ist eine abgespeckte Version dieses Glossars.
Gärten und Croissants
Authors: Messmer Susanne
Published: March 2009

Die etablierte koreanische Literatur gilt als sperrig, ist aber bei guter Übersetzung vor allem poetisch und sinnlich. Besonders jüngere Autoren vertrauen immer mehr auf Geschichten und die Haptik der Dinge. Eine Durchsicht der aktuell ins Deutsche übersetzten Romane und Erzählungen aus Korea
Neuerscheinungen auf dem Fachwörterbuchmarkt
Authors: Lück Erich
Published: March 2009

Der Sprachkundige braucht Fachwörterbücher. Oft erscheinen sie in wenig bekannten Verlagen. Wir möchten unsere Leser auf Neuerscheinungen aufmerksam machen. Die bibliographischen Angaben sind den Nationalbibliografien, Verlagsprospekten und anderen Quellen entnommen und werden ohne Gewähr wiedergegeben.
Bagger-Glossar (DE–EN/EN–DE) (2. Teil)
Authors: Ischganeit Thomas
Published: March 2009

Am 09. Juli 2003 wurde der feierliche Baubeginn für den Leipziger Citytunnel begangen und seit diesem Tag kann niemand mehr durch Leipzig gehen, ohne sich der vielen Baustellen und der sich darauf befindenden Hoch- und Tiefbautechnik bewusst zu werden. Auf jeder dieser Baustellen findet man Bagger in allen Formen, Farben und Größen. Man sieht die kleinen, sehr leistungsfähigen Minibagger, mittelgroße, beinahe alltäglich gewordene Bagger und die großen Ungetüme, die nach wie vor für ungläubiges Staunen sorgen. Diese am Institut für Angewandte Linguistik und Translatologie (IALT) der Universität Leipzig eingereichte Diplomarbeit „Bagger. Eine terminologische Untersuchung im Deutschen und Englischen“ verfolgte die Zielsetzung, einen Einblick in die vielen verschiedenen Baggertypen, einschließlich der unterschiedlichen Technologien, zu geben. Einen Hauptteil der Diplomarbeit bildete auch das im Folgenden in den Sprachrichtungen Deutsch-Englisch und Englisch-Deutsch abgedruckte Glossar. Es wurde mit dem Terminologieverwaltungsprogramm CATS erstellt und enthält 453 Datensätze mit 205 Begriffen, zu denen es 299 deutsche und 359 englische Benennungen gibt.
Plate Thickness and Specimen Size Considerations in Through-Thickness Tension Testing
Authors: Ludwigson DC
Published: March 2009

The through-thickness tension test to assess the resistance of plate steels to lamellar tearing often involves the welding of prolongs to either surface of coupons from a plate and the preparation of round through-thickness tension test specimens from the resulting weldments. Specimens are strained to failure in a universal testing machine, and reduction of area is calculated from before-and-after test measurements of minimum specimen diameter.

Experiments have been performed to evaluate the influence of coupon thickness on tensile properties measured with axisymmetric through-thickness specimens prepared from stud-welded assemblies. Results indicate that the influence of coupon thickness on tensile strength and reduction of area is small, provided that the separation between metallographically observable weld heat-affected zones in the coupon is at least as great as the specimen diameter. At smaller separations the intrusion of hardened prolongs and associated welds into the specimen gage length severely increases observed tensile strength and severely decreases observed reduction of area.

Test results led to an engineering rule of thumb for the minimum plate thickness that may properly be tested with welded through-thickness specimens of a given diameter:

minimum plate thickness = specimen diameter + 2 (penetration distance)

For a stud-welded specimen in which the penetration distance is about 0.457 mm (0.18 in.), the approximate minimum critical coupon thicknesses for 12.83, 9.07, and 6.40 mm (0.505, 0.357, and 0.252 in.) diameter specimens are 22.2, 19.1, and 15.9 mm (7∕8, 3∕4 and 5∕8 in.), respectively. Provided these minimums are observed, property differences attributable to specimen size are small.
Evaluation of Valid Nil-Ductility Transition Temperatures for Nuclear Vessel Steels
Authors: Satoh M , Funada T , Tomimatsu M
Published: March 2009

The causes of data scatter in nil-ductility transition (NDT) temperature were investigated to establish appropriate conditions for crack-starter bead welding. Drop-weight tests were carried out for nuclear vessel steels by changing the welding conditions to examine the effects of welding amperage and shapes of heat sinks on NDT temperature. The results show that preparation of the crack-starter bead by low welding amperage should not be allowed, because it makes the measured NDT temperature nonconservative, and that it is important to use a heat sink which increases the cooling rate of the specimen.

In addition, the authors propose methods for estimating the NDT temperature of nuclear vessel steels by using Charpy transition temperatures.
Influence of the Crack-Starter Bead Technique on the Nil-Ductility Transition Temperature of ASTM A572 Grade 55 Hot-Rolled Plate
Authors: Lundin CD , Merrick EA , Kruse BJ
Published: March 2009

An investigation of the nil-ductility transition (NDT) temperature of three heats of A572 Grade 55, hot-rolled steel plate, revealed a distinct and decided difference in behavior for specimens fabricated with a single-pass technique in comparison with those fabricated with the two-pass technique, which places the terminal weld crater at the bead center. The single-pass technique resulted in NDT temperatures 11°C (20°F) higher than those for the two-pass technique. Furthermore, the crack behavior was distinctly different at temperatures above the NDT, with the single-pass specimens showing progressively shorter cracks as the temperature was raised. This result is in contrast to that for the two-pass technique, which revealed no crack extension from the starter bead heat-affected zone (HAZ) above the NDT.

The metallurgical reasons for the observed behavior were determined by utilizing optical microscopy, scanning electron fractography, and microhardness methods. The toughness of the various regions of the HAZ and the base metal were correlated with the microstructure and NDT behavior. The differences in the NDT temperature are related to a toughening of the HAZ by the two-pass technique. The effect of this toughened HAZ on crack propagation and crack fracture morphology from the crack-starter bead, through the HAZ, and into the base metal was evaluated.
NDTT, RTNDT, and Fracture Toughness: A Study of Their Interrelationships Using a Large Data Base and Computer Models
Authors: Oldfield W , Server WL
Published: March 2009

The nil-ductility transition temperature (NDTT) test has been used extensively in naval ferritic steel applications since World War II. The use of the test results in fracture-safe design has extended into other structural steel industries, most notably those covered by the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code. The construction of nuclear reactor pressure vessels, in accordance with the ASME code, requires material specifications that utilize both the NDTT and Charpy V-notch test data; coupling the NDTT and Charpy V-notch data results in a “reference” temperature (RTNDT), which is either greater than or equal to the NDTT. [The RTNDT is defined as being greater than or equal to the NDTT; at RTNDT plus 33°C (60°F), three Charpy V-notch specimen results must exhibit a minimum of 68 J (50 ft · lb) of absorbed energy and 0.89 mm (35 mil) of lateral expansion. The energy requirement generally governs except for irradiated materials.] Interestingly, some materials generally have an RTNDT based upon the NDTT, while others have an RTNDT consistently greater than the NDTT since the RTNDT is governed by the Charpy V-notch data; (that is, the temperature at 68 J (50 ft · lb) minus 33°C (60°F) is greater than the NDTT). For example, the RTNDT for SA533B-1 plate steel is generally set by the Charpy data, but the RTNDT for SA508-2 forging steel (which is similar to SA533B-1) is typically controlled by the measured NDTT.

The science of fracture mechanics has also evolved since World War II, but the matching of transition temperature test results (NDTT, and RTNDT) with actual material fracture toughness (stress intensity) values is still uncertain. However, considerable progress in matching Charpy data with fracture toughness values has been made in recent years through the development of a large material property data base, which includes transition temperature and fracture toughness data. The work described in this paper builds on this research, and uses the same data base to examine the relationship between other transition temperature and toughness parameters. Computer modeling using stochastic procedures was employed to develop probability distributions which, by simulating the measurement of NDTT, clarify the interrelationships between NDTT, RTNDT, and fracture toughness. Predictions by the model of NDTT and RTNDT from dynamic fracture toughness data are in excellent agreement with measured values.
Fracture Mechanics Interpretation of the Drop-Weight NDT Temperature
Authors: Sumpter JDG
Published: March 2009

Difficulties associated with a fracture mechanics interpretation of the drop-weight nil-ductility transition temperature (DW NDTT) test are reviewed. Analytical correlations between the plane-strain fracture toughness for unstable fracture under dynamic loading Kld and DW NDTT presented in the literature usually assume that stress intensity can be calculated by postulating a small thumbnail-shaped crack subjected to dynamic yield stress loading. In practice, cracking continues to be extensive well above DW NDTT, while the region near the Hardex bead is subjected to high plastic strain. The paper presents analyses that attempt to take these factors into account, but none are felt to be entirely convincing. A more appealing explanation of why DW NDTT occurs at the temperature at which it does can be made by comparing the energy available from the specimen and tup with that required to propagate the crack. The author postulates that shear lip development may be the common factor which explains the empirically observed correlation between Kld and DW NDTT.
Numerical Solution of Electromagnetic-Field Eddy-Current Problems in Linear and Nonlinear Metallic Structures: The RMS Phasor and Instantaneous Approaches as Potential Tools in Nondestructive Testing Applications
Authors: Demerdash NA , Nehl TW
Published: March 2009

Two numerical analysis approaches for the determination of electromagnetic fields and induced eddy currents in nonmagnetic and magnetic metallic structures are presented. It is demonstrated how these techniques can best serve the purposes of nondestructive testing for material characterization etc. One method is based on instantaneous state-space or Crank-Nicolson discrete-time solution approaches, and is most suited for use with nonsinusoidal excitation wave forms and nonlinear materials. The other approach is based on a root mean square phasor concept and is best suited for sinusoidal excitation cases and linear nonmagnetic materials. Both methods are based on a magnetic vector potential formulation, and can be used in characterization of material conductivities and permeabilities. Results of application of the two methods to magnetic and nonmagnetic materials are reported.
Application of Reference Standards for Control of Eddy-Current Test Equipment
Authors: Wittig G , Beller M , Leider A , Stumm W , Weber HP
Published: March 2009

Within the German Standard Organization a working group was engaged with the task of investigating and specifying methods for testing the essential properties of eddy-current test equipment for application to the inspection of tubes with feed-through coil systems. For this purpose several reference standards are required; these contain artificial defects such as holes, longitudinal and transverse notches, and milled-off segments. Several materials are recommended for use in the usual frequency ranges.
A Macroscopic Model of Eddy Currents
Authors: Herman S , Prodan RS
Published: March 2009

In many applications only the macroscopic effects of eddy currents (those observable at the electrical terminals of an electromagnetic device) are of interest. In these cases eddy currents, hysteresis, and magnetic saturation are readily modeled using coupled electric and magnetic equivalent circuits.
An Eddy-Current Decay Technique for Low-Temperature Resistivity Measurements
Authors: Hartwig KT
Published: March 2009

The eddy-current decay technique developed by Bean for restivity determination is well suited for material characterization studies. The technique is shown to be an excellent method for determining the terminal solid-solution phase boundary in aluminum-gold (Al-Au), for following age hardening in dilute Al-Au alloys, and for detecting anisotropic electrical resistivity in cold-worked aluminum. Rapid and highly accurate restivities are measured with a basic circuit arrangement incorporating a digital oscilloscope.
A Multifrequency Approach to Interpret Defect Signals Superimposed by Disturbing Signals According to the Causing Defect Type and Size
Authors: Betzold K
Published: March 2009

A multifrequency algorithm is applied to suppress the effects caused by disturbing signals. The remaining defect signals then exist in a scalar (one-dimensional) form. The defect indication can be assessed by using artificial reference defects of known depths giving equivalent indication peaks. It is not possible, however, to distinguish which type of defect has really caused the read-out value. Before the defect size can be determined it is necessary to know the defect type. A method of distinguishing the different types of defects has been developed. The multifrequency algorithm is applied twice by adding at least one additional measuring value (this can be the real part or the imaginary part of an additional testing frequency) or replacing the test frequencies by entirely new ones. In both parallel channels the indications of the disturbing parameters are suppressed. Provided that the two channels react in different ways to the different types of defects, one obtains a two-dimensional read-out value. Displaying the two channels on an oscilloscope achieves the following results: (1) the disturbing signals are suppressed and concentrated at the zero point of the screen, (2) the defects give indications with different phase angles corresponding to the different defect types, and (3) the heights of the defect indications are correlated with the defect size. Using a computer program based on the permutation principle, the angles between the phase directions of the defect types can be optimized. Results are presented for the testing of built-in heat-exchanger tubes and welded joints and claddings.
In-Service Inspection of Steam-Generator Tubing Using Multiple-Frequency Eddy-Current Techniques
Authors: Dodd CV , Deeds WE
Published: March 2009

Although a rapid, accurate, and easy-to-use inspection method for steam-generator tubes is clearly needed, it is not entirely provided by our present eddy-current tests. The signals from eddy-current tests are affected by changes in tube wall thickness, the location and size of defects, the electrical conductivity, the magnetic permeability, and the tube-to-tube support spacing and denting (which changes the probe-to-tube spacing). Simultaneous variations in these test properties produce signals that are ambiguous in present commercial eddy-current instruments.

However, this type of multiple-property eddy-current testing can be done using pulsed techniques or, as in this example, multiple frequencies. A systematic, automated process has been developed at Oak Ridge National Laboratory (ORNL) to allow rapid development of accurate multiple-property eddy-current tests. It consists of the following steps:

1. Using a computer to design the coil, instrument, and operating conditions that give the best determination of the desired properties from a nonlinear combination of instrument readings.

2. Constructing the coil and instrument and testing with calibration specimens.

3. Using a large digital computer to take on-line instrument readings and perform the nonlinear property calculations.

4. Programming the on-board microcomputer in the instrument to perform the property calculations in the field.

The system has demonstrated a considerable improvement in the ability to measure wall thickness, tubing inside diameter, defect size, and defect location even in the presence of severe denting using laboratory standards. We are now proceeding with field testing of the instrumentation.
Multifrequency Eddy-Current Method and the Separation of Test Specimen Variables
Authors: Sagar A
Published: March 2009

The multifold accidental degeneracy present in eddy-current signals requires a multifrequency eddy-current examination of specimens to reduce the ambiguity in the determination of the nature of the source of the signals. The multiparameter technique for data analysis first developed by Libby is used for extracting information about multiple variables simultaneously present in the specimen. The effect of interaction between simultaneously present multiple variables on the results of the separation of these variables by this method of linear combination is discussed. It is suggested that the interactions between different regions of a discontinuity result in the lack of a unique relationship between the phase-amplitude characteristics and the depth of discontinuities of unknown geometry and orientation. The difficulty in the estimation of the diameter of the tube support-plate hole in the presence of magnetite (Fe3O4) in the crevice and methods for the determination of the inside dimensions of the tubing in regions with noncircular cross sections are discussed.
A Boundary Integral Equation Method for Calculating the Eddy-Current Distribution in a Long Cylindrical Bar with a Crack
Authors: Kahn AH , Spal R
Published: March 2009

We report calculations of the impedance of a long solenoid which surrounds a cylinder of conducting material containing a crack. The calculation is approached by expressing the eddy-current problem as an integral equation for the normal derivative of the magnetic field on the boundary of the conductor. This method is generally applicable to any cylindrical problem, regardless of the cross-sectional shape of the conductor. The boundary integral equation is solved in the case of the crack problem by discretizing and converting to a system of linear algebraic equations for the normal derivative of the field. The complex impedance is thereby obtained for a wide range of values of the ratio of crack depth to radius to skin depth. The results are displayed in graphical form, which gives the fractional changes of the real and imaginary parts of the impedance caused by the presence of the crack.
Microwave Eddy-Current Techniques for Quantitative Nondestructive Evaluation
Authors: Bahr AJ
Published: March 2009

The objectives of this work were to develop an electromagnetic scattering model that can be used to predict the scattering from a crack in a conducting surface and to evaluate the feasibility of using this model in conjunction with microwave-measurement techniques to determine the dimensions of such a crack. Such a theory has been developed, and its derivation is presented. Theory and experiment are compared for rectangular slots measured at 100 GHz, and the agreement is found to be good. The necessary measurement protocol for determining the dimensions of a crack is discussed, and an example of inverting the measured data to determine the dimensions of a rectangular slot is presented.
Theoretical Characterization and Comparison of Resonant-Probe Microwave Eddy-Current Testing with Conventional Low-Frequency Eddy-Current Methods
Authors: Auld BA
Published: March 2009

During the past two years small ferromagnetic resonators (FMR) operating at frequencies above 1000 MHz have been shown to offer promise as a new type of eddy-current probe for surface-breaking cracks in metals. Strong signals have been obtained from both electrical discharge machining (EDM) notches and actual fatigue cracks, and the FMR probes have been shown to have lift-off discrimination capability. Since the skin depth at these microwave frequencies is of the order of microns, the surface currents must penetrate the crack and, in order to detect its presence, the flaw detection mechanism must be necessarily somewhat different in detail than for conventional low-frequency eddy-current methods, where the flaw has dimensions typically of the order of the skin depth. A general theory, based on the Lorentz reciprocity relation and applicable to all types of detection systems, is reviewed and used as a vehicle for comparing microwave with low-frequency eddy-current techniques. In the microwave case, the FMR resonator is emphasized but other probe geometries are also considered.
Microwave Eddy-Current Experiments with Ferromagnetic Resonance Probes
Authors: Auld BA , Winslow DK
Published: March 2009

Experimental results obtained with the ferromagnetic resonance probe described in the companion paper by B. A. Auld are presented for a variety of real and fabricated flaws. Details of the apparatus are given with a brief explanation of the measurement technique used. Particular reference is made to the important property of discrimination between flaw and liftoff signals. An illustration of the edge-discrimination characteristics of the ferromagnetic resonance probe is shown.
Investigation into the Depth of Pulsed Eddy-Current Penetration
Authors: Sather A
Published: March 2009

Pulsed eddy-currents have been used successfully for a number of years to measure the wall thickness of thin-wall tubing. In studies of 88.9-mm (3.50-in.)-diameter stainless-steel tubing, wall thicknesses in the 0.254 to 0.762 mm (0.010 to 0.030 in.) range have been measured with an accuracy of ±10%. This paper describes an investigation of the relationship between the pulse length and depth of electromagnetic plane-wave penetration. Long pulses contain lower-frequency components than pulses of shorter duration. Therefore, longer pulses will penetrate much more deeply into a conductive material, assuring a 90 percent confidence level in the measurement of thicker materials. The pulsed eddy-current equipment used at Argonne National Laboratory (ANL) employs sampling of the detector waveform at discrete time intervals. Optimization of field-coil design for larger thicknesses of conductive material necessitates an increase in the pulse length. With a preliminary coil design, a penetration of 9 mm into stainless steel was achieved.
Effects of Truncation of a Predominantly Compression Load Spectrum on the Life of a Notched Graphite/Epoxy Laminate
Authors: Phillips EP
Published: March 2009

The fatigue behavior of a notched, graphite/epoxy (T300/5208) laminate subjected to predominantly compressive loading was explored in a series of constant amplitude and transport wing spectrum tests. Results of these tests indicated that (1) the amount of local (near the notch) buckling allowed in the tests significantly affected fatigue life; (2) spectrum truncation of either the high- or low-load end of the spectrum produced lives greater than those obtained in the baseline, complete-spectrum test, but life was much more sensitive to truncations at the high-load end; and (3) the Palmgren-Miner linear cumulative damage theory always predicted lives much longer than the actual spectrum loading test lives.
Fatigue Behavior of Silicon-Carbide Reinforced Titanium Composites
Authors: Bhatt RT , Grimes HH
Published: March 2009

The low cycle axial fatigue properties of 25 and 44-fiber volume percent SiC/Ti(6Al-4V) composites were measured at room temperature and at 650°C. At room temperature, the S-N curves for the composites showed no anticipated improvement over bulk matrix behavior. Although axial and transverse tensile strength results suggest a degradation in silicon-carbide fiber strength during composite fabrication, it appears that the poor fatigue life of the composites was caused by a reduced fatigue resistance of the reinforced Ti(6Al-4V) matrix. Microstructural studies indicate that the reduced matrix behavior was due, in part, to the presence of flawed and fractured fibers created near the specimen surfaces by preparation techniques. Another possible contributing factor is the large residual tensile stresses that can exist in fiber-reinforced matrices. These effects as well as the effects of fatigue testing at high temperature are discussed.
Ecological Factors in the Selection of Representative Species for Thermal Effluent Demonstrations
Authors: Bogardus RB
Published: March 2009

A number of various federal and state guideline documents that have been issued for use in demonstrations under Section 316(a) of the Federal Water Pollution Control Act contain criteria to be applied in selecting organisms that are representative of the aquatic community at the proposed power plant site. This paper reviews three Section 316(a) case histories in which these selection criteria are applied and evaluates the usefulness and practicality of the methodology. The conclusion is reached that the basic approach of using representative species is practical but that the reliability and accuracy of the selection process is only as good as the available data on the seasonal distribution and life histories of the aquatic community in the receiving waters. A baseline field monitoring program designed to gather adequate data for the Section 316(a) representative species selection and evaluation process is proposed.
Power-Plant-Related Estuarine Zooplankton Studies
Authors: Sage LE , Olson MM
Published: March 2009

Increased emphasis is being placed on formulating a particular study design that will generate the greatest amount of relevant information for a particular problem. This is a case history of a study design as it evolved from one level of information to another, yielding both quantitative and biologically meaningful information.

In-plant studies examining the effects of entrainment on zooplankton and field studies examining zooplankton abundance, composition, and distribution in the Chesapeake Bay in the vicinity of Calvert Cliffs Nuclear Power Plant (Baltimore Gas and Electric Co.) have been conducted from 1974 to the present. The evolution of these studies, with particular emphasis on design and statistical treatment, is discussed. Entrainment study designs evolved from discrete sampling episodes at 4-h intervals over 24 h to a time-series sampling design in which sampling took place every 30 min over 24 and 48-h periods. The near-field study design and sampling methods have included replicated net tows, using 0.5-m nets, and replicated and nonreplicated pumped samples, using a high-speed centrifugal pump. The relative collecting characteristics of sampling methods are described; study designs and applicable data analysis techniques are evaluated with respect to their ability to detect plant effects within defined limits of personnel and budgetary constraints.
Assessment of Effluent Impacts Through Evaluation of Periphyton Diatom Community Structure
Authors: Weitzel RL , Bates JM
Published: March 2009

Evaluation of changes in periphyton diatom community structure proved to be a useful means of assessing the impact of an electroplating waste discharge on the biota of the Muskingum River in Ohio. The copper waste discharge decreased species richness and species diversity (as indicated by the Shannon-Weaver and Brillouin indexes) of the diatom community collected from artifical substrates. Corresponding evenness and redundancy components also indicated stressed conditions.

Short-count intervals of detailed readings were compared to determine the ability and sensitivity of these shorter efforts of enumeration to respond to community changes. Counts of 500 diatom cells, while accurately responding to gross perturbations when applied in the form of biotic indexes, were somewhat inconsistent and apparently insensitive to minor shifts in diatom community structure. Counts of 1000 diatom cells more closely paralleled the trends developed by the 5000-cell long counts. Extension of the diatom counts beyond 2000 cells yielded less species information for the manhours required, and it was at this level that the species curve began to approach an asymptote.
Assessment and Prediction of Impacts of Effluents on Communities of Benthic Stream Macroinvertebrates
Authors: Kovalak WP
Published: March 2009

Diversity indexes, particularly those based on information theory, have been widely promoted as the best method for assessing the impact of effluents on macroinvertebrate communities. Despite their superiority, neither the Shannon-Weaver index (SWI) nor the Brillouin index (BI) is universally applicable. The SWI is preferred where effluents are selective (for example, organics) and BI preferred where effluents are nonselective (for example, heavy metals). Despite their simplicity, it should be remembered that diversity indexes supplement, not replace, community analyses based on species richness and population densities. Covariance analyses and more tightly defined stratified sampling programs are discussed as ways of improving the accuracy of density estimates.

Impact prediction depends on models predicting changes in species richness and population densities. A mechanistic model predicting changes in species richness as a function of oxygen supply and demand is offered as a step in this direction. Despite its accuracy in undisturbed streams, the applicability of the model to organic and thermal pollution awaits testing. Implications of the model for impact prediction are discussed.
Investigation of Injection Problems of a Produced Water Disposal System with Emphasis on Redox Potential Measurement for Solving Injection Problems in the Field
Authors: Stone PJ
Published: March 2009

Scale inhibitors will solve calcium carbonate deposit problems, but not aeration problems. Aeration of produced water and consequent iron oxide precipitation in the oil field is a common mechanical failing that can lead to serious loss of injectivity and even complete loss of injection wells being used for disposal or water flooding. Redox potential has been successfully measured in the field and, in one case, has correlated well with suspended iron oxide and oxygen concentration measurements.
Electrochemical Hydrogen Patch Probe Correlated to Corrosion Rate in a Slightly Sour Water Flood
Authors: Dexter R
Published: March 2009

An externally mounted electrochemical cell has recently been developed that can be patched onto the outside of steel pipes and vessels. This probe monitors the amount of hydrogen diffusing through the steel walls.

The hydrogen patch probe was mounted on a slightly sour water flood line 9.1440 m (30 ft) upstream of a corrosion coupon rack. Real time hydrogen current levels are compared to weekly weight loss corrosion measurements for a period of six months. Areas of agreement and disagreement are discussed.
Characterization of Unstable Waters by Seeded Crystal Growth Techniques
Authors: Liu S-T , Griffiths DW
Published: March 2009

The seeded crystal growth experiment has been examined as to its applicability for investigating the growth and inhibition of water-born deposits. Basic and practical aspects of the experiment are reviewed in this paper, and examples are cited to demonstrate experimental capabilities. In one of the examples, it is shown that the experiment can be conducted in a natural oil-field brine to resolve small differences in inhibitor performance. It is concluded that the seeded crystal growth experiment is the best available procedure for characterizing unstable waters where reproducibility and reliability are of major importance.
Mobile Wellhead Analyzer for the Determination of Unstable Constituents in Oil-Field Waters
Authors: Hoke SH , Collins AG
Published: March 2009

A brine analyzer was designed that measures pH, redox potential (Eh), oxygen, conductivity, sulfide ion (S=), HCO3−, CO3=, and carbon dioxide in oil-field water at the wellhead. When oil-field brine samples are collected in the field and transported to the laboratory for analysis, many of the unstable constituents change in concentration. The amount of change depends on the sampling method, sample storage, ambient conditions, and the amounts of the constituents in the original sample. Thus, an analysis of the brine at the wellhead is necessary to obtain reliable data.
Some Factors Contributing to Decreased Well Efficiency During Fluid Injection
Authors: Johnson AI
Published: March 2009

Many factors affecting fluid injection through wells involve clogging of the well and injection zone. Extensive field research carried out in the Grand Prairie Region of Arkansas, supported by special laboratory testing, involved the injection of surface waters into native waters of the local aquifers. The principal causes of clogging were found to be gas binding or air entrainment in the injection zone, suspended particles in the injection fluid, bacterial contamination of the injection zone by the injection fluid and subsequent clogging by bacterial growths, mechanical jamming of the injection zone and gravel pack around the well caused by particle rearrangement when the direction of fluid movement into and through the injection zone is reversed, and chemical reactions between the injection fluid and the native groundwater or the particles in the injection zone. The results indicated that the efficiency of the injection well could be reduced by as much as 50 percent by such factors and that treated injection fluid therefore would be advisable.

Other problems in operating an injection well included the effects of injecting fluid of a different temperature and viscosity and the interpretation of fluid-level changes in the injection zone during the injection tests because most clogging was found to take place within a few feet of the injection well.

Laboratory tests were used successfully to make preliminary estimates of the hydraulic characteristics of the injection zone prior to field testing of those properties. Laboratory experiments also showed that a permeability reduction of as much as 45 percent resulted from compaction of the gravel pack caused by surging action during well development and from the pumping and injection tests.
Influence of Formation Clays on the Flow of Aqueous Fluids
Authors: Hower WF
Published: March 2009

Most sandstone formations contain clays that can have a significant effect on the flow of aqueous fluids. The clays most frequently detected are smectite, mixed layer, illite, kaolinite, and chlorite. All of these clays are capable of migrating and causing permeability damage when they are contacted by waters foreign to the formation. Normally, these waters alter ionic environments around the clays, which causes the clays to be dislodged from their original positions. Thus, any time clay is present in the rock, it can be assumed that permeability damage can occur. The degree of damage will depend upon the concentration and types of clays present, their relative position in the rock, the severity of the ionic environmental change, and fluid velocity.

Aqueous fluids that may be classed as foreign waters are effluents being injected into disposal wells, fresh water storage in underground aquifers, flooding waters used for secondary oil recovery, and waters that may contact hydrocarbon-producing formations during numerous phases in a well's life.

Permeability damage has been minimized in oil and gas wells through the use of the potassium and ammonium ions. These ions will control the amount of water adsorbed by clays but, since they are exchangeable, they do not affect permanent protection against clay migration. A hydroxy-aluminum ion has been used effectively for formation treatment, but its use is limited to formation temperatures below 93.3°C (200°F) and where pH values do not vary more than a few integrals from neutral. The most effective material that provides long-time control of clay migration under a large variety of conditions is a select group of organic polymers. These polymers are strongly adsorbed by clays, thus helping to prevent clay movement in the rock matrix.
Ion-Exchange Softening of High-Solids Waters
Authors: Anderson RE
Published: March 2009

Extension of conventional sodium-cycle softening to high-solids waters is restricted by the fundamental properties of ion-exchange systems. Resin performance is a function of water composition, both in regard to total dissolved salts and the fraction of hardness salts. Volume treated to hardness breakthrough, and hardness leakage can be estimated with a useful degree of accuracy by use of equilibrium relationships. Adjustment of performance for different levels of regeneration can be made by use of empirical data relating degree of regeneration to salt dosage.

Waters with total dissolved solids above 5000 ppm can be softened by use of weak acid resins in many cases. Depending on the nature of the salts present, a weak-acid resin may be used in either a sodium or hydrogen cycle. Although acid and base are required for regeneration, chemical costs are competitive with conventional softening in many situations.

Softening of saturated brines requires use of chelating resins showing high selectivity for hardness ions over sodium ion.
A Rationale for Testing to Establish Suitability for an End-Use Application
Authors: Evans RE
Published: March 2009

The methodology necessary for selecting physical test procedures relevant to end-use applications is discussed. Emphasis is placed on the complex behavior of plastics and the fact that the physical properties of polymers cannot be presented as unchanging “typical values” that universally describe material behavior.

A basic rationale necessary to develop a sound philosophy of testing is first developed. An integrated approach of describing all physical tests simply as input/output measurements under given boundary conditions is presented. Three classes of test methods, that is, fundamental tests, component or practical tests, and hybrid tests are defined. The importance of avoiding hybrid types of tests is illustrated. An assessment of standard ASTM test methods is presented. Guidelines are established for selecting relevant physical testing procedures.