bluuebunny/crossref_metadata_2025_split huggingface dataset:
Some New Fractographic Features in the Fatigue of High-Strength Aerospace Alloys
Authors: Cina B , Eldror I , Kaatz T 
Published: December 2008

The object of this research was to further a systematic fractographic study of fatigue in aerospace materials to facilitate failure investigations of actual components. Smooth and notched laboratory specimens were fatigue tested in pulsating tension and in alternating stress at a frequency of 1 to 2 Hz and at stresses that gave failure in 103 to 105 cycles. Fractures were examined by stereoscopic and scanning electron microscopes.
A ridge structure that had been previously observed in aluminum alloys that emanates from fatigue origins but precedes the formation of striations was observed in ultra-high-strength steels. The implications of such ridges in the mechanism of fatigue cracking are discussed. Not all the steels studied showed fatigue striations, and failure mechanisms not specific to fatigue were frequently observed.
Such nonconformity of fractographic features increased with the tensile strength of the steels. Secondary cracking was sometimes found to be a more reliable method of identifying fatigue failure in some of these steels. Intergranular cracking at prior austenite grain boundaries was also frequently observed, although its formation appeared, on occasion, to be related to the attainment of a minimum level of stress intensity. Hydrogen from the environment also probably played a role in such intergranular cracking, as indicated by distinct hairlines on the fracture surface. Intergranular crack surfaces also sometimes showed unexpected crystallographic features.
For the aluminum alloys, further quantitative relationships have been established between the total number of striations in the development of the crack and the number of fatigue cycles in the entire fatigue test. This enables the fatigue stress to be estimated where unknown.
Counting striations in the steels was found to be very difficult and unreliable. However, trends in 4340 steel were found to be akin to those in aluminum alloys. Ridge formation in the aluminum alloys did not appear to be related to specimen geometry.
Swelling of 20% Cold-Worked Type 316 Stainless Steel Fuel Pin Cladding and Ducts
Authors: Makenas BJ 
Published: December 2008

The data base of Type 316 stainless steel 20% cold-worked cladding swelling measurements from mixed-oxide fuel pins irradiated in Experimental Breeder Reactor-II (EBR-II) has been extended to a fast (E &gt; 0.1 MeV) fluence of 17 × 1022 neutrons (n)/cm2. Previously, the data base from actual fuel pins included only developmental and Fast Flux Test Facility (FFTF) first core cladding of 5.84 mm (0.230 in.) diameter irradiated to a maximum fast fluence of 13 × 1022 n/cm2. Recent data includes FFTF fourth core material and cladding samples 7.37 mm (0.290 in.) in diameter that were taken from various advanced oxide experiments. Differences in incubation parameter between the swelling of first and fourth core material were at first attributed to heat-to-heat differences, but later were shown to be more properly attributed to different experimental and cladding fabrication parameters. Peak swelling values have now reached 40% volume change.
Swelling in cold-worked Type 316 stainless steel ducts used in EBR-II has also been evaluated using coupons cut or punched from irradiated duct faces. Substantial differences in swelling between faces, which reflect the local reactor environment, have been observed. More recently, duct material at the same maximum fluence as that of the fuel pin cladding has been added to the data base and compared to the swelling of EBR-II cladding.
Helium and Displacement Damage Produced by 600 MeV Proton Beams in High Purity Aluminum
Authors: Gavillet D , Gotthardt R , Martin J-L , Green SL , Green WV , Victoria M 
Published: December 2008

Pure aluminium samples (99.9999%) have been irradiated in the Proton Irradiation Experiment (PIREX) installed in the 600 MeV proton beam of the accelerator in the Swiss Nuclear Research Institute (SIN), at temperatures between 400 K and 500 K and displacement doses between 0.9 and 5 displacements per atom (dpa). Average displacement rate is 3.5 × 10-6 dpa/s.
The specimens were analyzed for both 3He and 4He. Measured helium content is 215 atomic parts per million (appm)/dpa. No diffusional spreading of sodium or helium was measured. The helium bubble structure was examined and shows a swelling of 0.16% at ∼5 dpa.
Mold Temperature Measurement for Glass-Pressing Processes
Authors: Holman RA 
Published: December 2008

The largest use of radiation thermometers within Corning Glass Works is for mold temperature measurement for the glass-pressing process. Pressing television panels at today's high quality would be very difficult without a mold temperature measurement system and the computer manipulation of the quality control data to supervise the mold temperature control loop.
The most critical part of a television panel is the inside surface curvature. The ideal surface is usually defined as a spherical surface. The tolerance for a normal TV panel is ±0.30 mm (±0.012 in.). High resolution display panels are more critical, having a dimensional tolerance only one half as large as TV panels. Panel curvature is a direct (but negative) function of mold temperature. Every 1°C increase in mold temperature results in the panel center being 0.025 mm (0.001 in.) shorter (flatter). Random dimensional variations within a panel take up most of the dimensional tolerance. The result is that each mold is controlled to its own individual temperature set point, ±1°C.
Hot panel and cold panel curvature measurements are correlated by a process computer and used to update the mold temperature set points. The same computer adjusts the mold cooling air to maintain the required mold temperatures.
From the temperature measurement standpoint, the significant problem is the changing emissivity of the mold surface when the mold is new or reconditioned. The selection of a radiation thermometer with a short wavelength was an obvious choice to minimize the effect of emissivity variations. On the negative side, the potential interference from reflected ambient light would require careful shielding. A silicon cell thermometer was chosen for this system. The silicon cell thermometer is a very fast response instrument—that attribute is not required in this specific application but is used in high-speed pressing processes such as automotive headlights.
Radiation Thermometry for Semiconductor Crystal Growing Furnaces
Authors: Helgeland W 
Published: December 2008

Single crystals of silicon produced by the Czochralski process are used widely in the production of integrated circuits and other electronic devices. Recent advances in automation of industrial equipment for this process have led to the application of a dual wave band radiation thermometer. The instrument system automatically performs certain critical temperature measurements. In nonautomated equipment, these measurements require the judgement of a trained human operator.
The difficulties of measuring and controlling the temperature at the critical location are discussed, especially with regard to detecting the meltdown end point and to initially establishing the correct temperature for seeding. A description is given of the customized temperature measurement system, which is based upon an existing ratio radiation thermometer. Thermometer output characteristics are described.
Closed-Loop Temperature Control for High-Frequency Electric-Resistance Tube and Pipe Welding Mills
Authors: Udall HN 
Published: December 2008

A system for closed-loop temperature control of high-frequency welding systems has been sought for over 20 years; however, until recently the available instrumentation for temperature measurement was not capable of operating in the conditions prevailing on a typical tube or pipe mill. The major problems are: 1. A very small available target size. 2. The positional instability of the target due to changes in incoming material dimensions and mill parameters. 3. The presence of large quantities of cooling water in the immediate weld area with attendant smoke and steam. 4. The possibility of an occasional momentary arc occurring in the weld area under certain mill operating conditions. 5. The very small ratio of the heated material to the power available for heating, leading to the possibility of extremely rapid temperature changes. 6. The presence of a small but significant amount of radio frequency (RF) radiation in the immediate vicinity of the weld.
A combination of the latest developments in color ratio pyrometry, in modern digital control techniques, and in coolant control in the weld area has led to the development of a closed-loop control system which will hold the mean weld temperature constant while rejecting the momentary disturbances to the temperature signal which are inevitable in a normal production process.
A Survey of Asbestos-Related Disease in Trades and Mining Occupations and in Factory and Mining Communities as a Means of Predicting Health Risks of Nonoccupational Exposure to Fibrous Minerals
Authors: Ross M 
Published: December 2008

A review based on 36 published epidemiological studies is given of disease patterns that have developed among industrial workers, miners, and millers who had been exposed to dusts of one or more of the commercial asbestos minerals or to dusts from minerals perceived to be asbestos-like. Health data are also reviewed for individuals exposed to asbestos dusts in nonoccupational settings. From the published reports it is clear that there are very significant differences in the health effects of the several asbestos or asbestos-like minerals
Of the commercial asbestos utilized in the United States, about 95% has been chrysotile or “white” asbestos, about 2% amosite or “brown” asbestos, and about 2% crocidolite or “blue” asbestos. The common white asbestos has had the least effect on those occupationally exposed, whereas blue asbestos has had the most effect. Despite the wide dissemination of white asbestos in our environment—in schools, homes, public buildings, brake lining emissions, and so forth—there is little evidence that the very frequent non-occupational exposures to this form of asbestos have caused any harm. On the other hand, nonoccupational exposure to blue asbestos has been conclusively proven to have caused significant mortality. The different health effects of the various forms of asbestos require different regulatory responses and remedial actions.
Fiber Definition in Occupational and Environmental Asbestos Measurements
Authors: Chatfield EJ 
Published: December 2008

Determination of asbestos in occupational air samples is performed by phase contrast optical microscopy (PCM). Any particle with an aspect ratio exceeding 3:1 is considered to be a fiber, and in the PCM method, all fibers longer than 5 µm are counted. Asbestos is measured in ambient air by electron microscopy, and all fibers that can be identified as asbestos are counted. The asbestos fibers are identified by using observations of morphology and a combination of selected area electron diffraction (SAED) and energy dispersive X-ray analysis (EDXA) measurements. The cost of absolute fiber identification, in the legal sense, is often prohibitive and, depending on previous knowledge of the situation, a combination of measurements acceptable as adequate identification may be agreed upon before the analysis is made.
The published information about the relative toxicity of fibers as a function of their dimensions indicates that the fiber definition used in PCM fiber counting excludes many fibers known to induce tumors in animals. For asbestos measurement in ambient air samples, no clear definition of an asbestos fiber exists, and all fibers within the toxic size ranges are examined. Those fibers that are compositionally and crystallographically consistent with asbestos are incorporated into the fiber count.
The relevance of fiber definition in both occupational and ambient air measurements is discussed. The author suggests that the best current information on biological effects should be used to define a new carcinogenicity index, thus bypassing the requirement for arbitrary fiber definitions.
What is Talc?
Authors: Clifton RA 
Published: December 2008

Talc is a hydrated magnesium silicate produced by the metamorphosis of dolomite and quartzose rocks or by the hydrothermal alteration of ultramafic and mafic rocks. As the changes are rarely complete and uniform, the rocks usually contain one or more other minerals. In pure form it is the softest of minerals. Talc is an extremely useful and economically important mineral and is, like most materials, hazardous to a degree.
This paper takes the position that talc is a victim. It is a victim of the imprecision of mineral terminology, which does not distinguish between the fibrous and nonfibrous varieties of several amphiboles. It is a victim of the terminology of its own industry, which sold “fibrous talc” for many years. It is victimized because precursor minerals in fibrous habit produce pseudomorphic talc fibers. Those same fibers are sometimes unaltered and present in talc in just enough quantity to give a near truth to claims that talc contains asbestos. Talc is a victim of monitoring methods that are totally nonspecific and call each elongate particle of whatever origin a fiber and, by analogy, asbestos. Most especially, talc is a victim of imprecise asbestos definitions, which allow the inclusion of most amphibole particles of some elongation in those definitions.
Consequences of Using Improper Definitions for Regulated Minerals
Authors: Thompson CS 
Published: December 2008

Present trends in government activities aimed at regulating mineral dst exposures in the workplace and in the outside environment indicate a future of extremely difficult, if not impossible, operating conditions for producers and users of mineral products. Using inaccurate and simplistic definitions, governmental agencies have unknowingly indicted a large part of the earth's crust as being extremely hazardous and, in the case of asbestos, cancer causing. Using a simplistic definition of what a fiber is, the government has continued to expand the number and variety of minerals suspected of being as hazardous as or worse than asbestos. This is made clear by recent publications of the National Institute for Occupational Safety and Health (NIOSH) and the Mine Safety and Health Administration (MSHA). The NIOSH paper lists, in addition to asbestos varieties, some 40 “nonasbestos” minerals “which may occur in a fibrous state.” MSHA's publication names 152 “minerals that may occur in fibrous habit.”
Talc is one of the nonfibrous minerals that has become a maligned mineral product, partly because of the rather loose use of the term “talc” by industry in referring to a broad variety of minerals, and partly because of definitions applied to associated minerals present in many talc deposits.
Unless the mineral industry, producers, and consumers, as well as mineral scientists, present a united front in demanding participation in the definition of minerals and mineral products by health researchers and scientists, mineral-related businesses will be confronted by regulations that will be, in the author's estimation, not only oppressive and in many cases prohibitive, but also unnecessary.
Recent Experiences with Corrosion Beneath Thermal Insulation in a Chemical Plant
Authors: Long VC , Crawley PG 
Published: December 2008

Corrosion of carbon and stainless steels under wet thermal insulation can be a serious problem and can be especially prevalent in the humid Gulf Coast area. This paper discusses an inspection program that has been in progress since late 1982 at a ten-year old chemical plant located at La Porte, TX. The program is intended to determine the extent of corrosion damage to major pieces of equipment that has occurred under inhibited calcium silicate insulation finished with aluminum jacketing and to recommend remedial action.
Key elements of a successful inspection program are discussed. A series of pictures is presented that correlate visual external telltale signs with corrosion beneath the insulation. At the time of writing, significant localized corrosion of carbon steel has been found, as well as evidence of incipient stress corrosion cracking of austenitic stainless steel.
Multiaxial Fatigue
Authors: Miller KJ , Brown MW 
Published: December 2008

Description
Combines international schools of thought on the behavior of materials subjected to multiaxial fatigue. Gives designers simplified methods of analysis that are applicable to practical situations involving complex street cycling. Shows that significant progress has been made in predicating finite fatigue life behavior, namely, that induction of stresses on two or three axes in fatigue experiments provides valuable information on the micro mechanisms of fatigue crack formation and growth and the uses and limitations of multiaxial correlation factors.
Radiation-Induced Changes in Microstructure: 13th International Symposium (Part I)
Authors: Garner FA , Packan NH , Kumar AS 
Published: December 2008

Description
STP 955 resulted from a major international forum for the exchange and discussion of both the fundamental and technological aspects of behavior change in materials exposed to radiation environments. 66 papers comprise this book whose contents have been categorized into seven distinct technical areas: radiation-induced defects and their diffusion; neutron-induced swelling; charge particle-induced swelling; theory of swelling and irradiation creep; microstructural evolution; solute segregation and phase stability; and effects of implantation.
Degradation of Metals in the Atmosphere
Authors: Dean SW , Lee TS 
Published: December 2008

Description
Paper present current research results on the corrosion of metals in the atmosphere, show current thinking on mechanisms of atmospheric corrosion, and document how changes in the atmosphere have affected the corrosion of metals. This book provides convenient access to technical data from recent tests, long term test programs, and field experience, including data on new materials of construction.
Influences of Fragmentation on Three Species of Native Warmwater Fishes in a Colorado River Basin Headwater Stream System, Wyoming
Authors: Compton Robert I. , Hubert Wayne A. , Rahel Frank J. , Quist Michael C. , Bower Michael R. 
Published: December 2008

Abstract
We investigated the effects of constructed instream structures on movements and demographics of bluehead suckers Catostomus discobolus, flannelmouth suckers C. latipinnis, and roundtail chub Gila robusta in the upstream portion of Muddy Creek, an isolated headwater stream system in the upper Colorado River basin of Wyoming. Our objectives were to (1) evaluate upstream and downstream movements of these three native species past a small dam built to divert irrigation water from the stream and a barrier constructed to prevent upstream movements of nonnative salmonids and (2) describe population characteristics in stream segments created by these structures. Our results indicated that upstream and downstream movements of the three target fishes were common. Fish of all three species moved frequently downstream over both structures, displayed some upstream movements over the irrigation diversion dam, and did not move upstream over the fish barrier. Spawning migrations by some fish into an intermittent tributary, which was not separated from Muddy Creek by a barrier, were observed for all three species. Both the irrigation diversion dam and the fish barrier contributed to fragmentation of the native fish populations, and considerable differences in population features were observed among segments. The instream structures may eventually cause extirpation of some native species in one or more of the segments created by the structures.
Influence of the Moran Effect on Spatiotemporal Synchrony in Common Carp Recruitment
Authors: Phelps Quinton E. , Graeb Brian D. S. , Willis David W. 
Published: December 2008

AbstractClimatic variation and dispersal are two primary factors thought to induce recruitment synchrony in fish populations. We hypothesized that climate factors correlated across a broad geographical scale (i.e., the Moran effect) would induce synchrony in recruitment for common carp Cyprinus carpio among 18 glacial lakes across a 175‐km2 area in eastern South Dakota. Cross‐correlation analysis indicated that common carp population fluctuations were highly synchronous among lakes. To evaluate the influence of the Moran effect on recruitment, we examined several candidate models using an information‐theoretic approach. The model with the most support included the interaction of temperature, precipitation, and wind during the open‐water period. This model indicated that the effects of any one of these climate variables on recruitment strength depended on the level of each of the other variables in any given year. Our results suggest that common carp populations in the Midwestern United States exhibit synchronous recruitment across regionwide geographic areas as a result of climatic variability.
Factors influencing trends of polychlorinated naphthalenes and other dioxin-like compounds in lake trout (Salvelinus namaycush) from Lake Ontario, North America (1979–2004)
Authors: Gewurtz Sarah B. , Lega Rocsana , Crozier Patrick W. , Whittle D. Michael , Fayez Laila , Reiner Eric J. , Helm Paul A. , Marvin Chris H. , Tomy Gregg T. 
Published: December 2008

AbstractConcentrations of polychlorinated naphthalenes (PCNs) were determined in archived lake trout (Salvelinus namaycush) from Lake Ontario, North America, collected between 1979 and 2004 to evaluate their temporal trends and the factors influencing their trends. Concentrations of PCNs, as well as polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), and non- and mono-ortho-substituted polychlorinated biphenyls (DL-PCBs), which were measured for comparative purposes, declined by eight-, seven-, and fivefold, respectively, between 1979 and 2004. Apparent elimination rate constants (k2) were calculated as the slopes of the regression lines of concentration versus time for PCN, DL-PCB, and PCDD/F congeners to compare the rate of decrease among congeners within and between compound classes. The k2 values for PCNs that had two pairs or three adjacent carbons unsubstituted with chlorine (congeners that can be biotransformed by vertebrates) were not significantly different from zero, indicating no decline in fish. For PCN congeners having no adjacent carbons unsubstituted with chlorine, the k2 values generally increased with hydrophobicity and degree of chlorination. This pattern differed from that of PCDD/Fs and DL-PCBs and from previous findings for non-DL-PCBs, for which the rate of contaminant decline decreased with hydrophobicity, and the pattern also differed from expectations based on thermodynamics. Differences in the rate of decline of PCN congeners may be caused by changes in source or mixture formulations over time and/or metabolic dechlorination of the less stable, higher-chlorinated PCNs 73, 74, and 75 to lower-chlorinated congeners. Based on suggested dioxin toxic equivalency factors, PCN concentrations in these whole lake trout may be sufficient to trigger consumption restrictions in Ontario, Canada, and our results suggest that PCNs merit incorporation into monitoring and assessment programs.