bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of Low-Alloy Steel Using a Sequential Atomic Absorption Spectrophotometer Equipped with an Autosampler
Authors: Klein AA
Published: March 2009

A sequential atomic absorption spectrophotometer equipped with an autosampler and a programming capability by way of magnetic cards is being used to determine the concentrations of aluminum, titanium, vanadium, manganese, nickel, copper, chromium, and molybdenum in steel. The eight elements were divided into two categories for analysis: (1) the more sensitive elements—maganese, nickel, copper, chromium, and molybdenum and (2) the less sensitive elements—aluminum, titanium, and vanadium. To determine the concentrations in steel of the more sensitive elements, a 1.00-g portion of a steel sample is dissolved and diluted to 200 ml. Since the concentrations of some of these elements in the steel may be as high as 2.00 percent, analytical lines other than the most sensitive ones are used for these elements. The concentrations in steel of the less sensitive elements range from 0.00 to 0.50 percent and are determined by dissolving a 2.00-g portion of a steel sample and diluting the solution to 100 ml. The instrument is calibrated by using spiked standards. These standards contain iron background and acid concentrations approximately equal to those of the specimen solutions.

The system has been on line since September 1979 and is used for steel product check analyses. The accuracy in determining the concentrations of these eight elements with this system is as good as or better than that achieved with the other methods used.
Recent Advances in Ion Chromatography
Authors: Girard JE , Glatz JA
Published: March 2009

The chromatographic separation and quantitation of highly ionic species was a difficult problem until recently. Ion chromatography (IC) represents a solution to this analytical problem.

Nonsuppressed IC offers a new alternative method to practitioners of IC. Since a suppressor column is not necessary for this method, the time required to regenerate the suppressor column is saved. Better chromatographic efficiency is achieved with the suppressor removed. Peak reversal, a problem associated with the suppressor column, is also eliminated. The sensitivity for Cl− (0.5 ppm) is comparable to that of conventional suppressed IC. The sensitivities for NO3− (1.25 ppm) and SO42− (1.25 ppm) are only slightly less than those observed for the conventional technique.
Use of On-Line Atomic Absorption in a Power Plant Environment
Authors: Skriba MC , Gockley GB , Battaglia JA
Published: March 2009

Westinghouse has been conducting a program to upgrade the purity of primary-loop cooling water in pressurized water reactor (PWR) nuclear power plants, and a method was needed to measure cationic impurities such as calcium, magnesium, and aluminum in the 0 to 10-ppb range. After examination of alternative methods, a Perkin-Elmer Model 5000 flameless atomic absorption (AA) unit with an AS-40 auto-sampler was selected and tested on line in a nonlaboratory, auxiliary building area of an operating nuclear power plant.

Electrical isolation, dust and dirt protection, supplemental system cooling, and sample preconditioning all had to be provided to enable what is essentially a laboratory instrument to function in the more hostile plant environment. Some problems arose in the electronics of the spectrophotometer portion of the instrument, such as loss of preprogram instruction, multiple false readings, and loss of averaging functions. These problems were not of major proportions, however, and the system was able to track contamination levels through plant shutdown for refueling and consistently monitor impurities in the sub-parts-per-billion range. It has been shown that with the new automated flameless AA systems, high-quality analyses can be obtained on line and without the need of a highly trained spectroscopist as an operator.
Fracture Toughness of Glass Using the Indentation Fracture Technique
Authors: Smith SS , Magnusen P , Pletka BJ
Published: March 2009

Half-penny shaped cracks called median vents are formed about indentations made with sharp indenters in brittle materials. Two fracture mechanics analyses for the formation of median cracks exist and constitute a basis upon which the fracture toughness (Kc) can be obtained from indentation fracture experiments. However, little attention has been directed toward assessing the applicability of indentation fracture as a method for determining Kc in brittle materials.

In this paper, such an evaluation of indentation fracture was performed on various glasses. Initially, indenter load-median crack length data were used to establish that the model of Lawn and Fuller described best the indentation fracture data. Their analysis was used to calculate Kc-values, which were compared to Kc-values obtained with conventional fracture mechanics methods. The difference in Kc-values determined by the two methods was ∼30 percent or less for normal glasses (glasses containing network modifier ions), and good reproducibility of indentation fracture Kc-values was found. A qualitative ranking of Kc by these two methods, however, did not agree. An evaluation of Kc by indentation fracture was not possible in anomalous (silica-rich) glasses due to the presence of cone cracks.
Static and Dynamic Fracture Behavior of Oil Shale
Authors: Costin LS
Published: March 2009

The fracture toughness of a rich grade of oil shale (high kerogen content) was determined as a function of loading rate (˙K1) and orientation of the crack with respect to the bedding planes. Several independent test methods were employed in order to attain a wide range of loading rates and to examine the effect of specimen size and configuration on the test results. The test methods used in this series of experiments include ASTM Test for Plane-Strain Fracture Toughness of Metallic Materials (E 399 - 78a), the J-resistance curve method, the short rod method, and the instrumented Charpy impact test. The static tests were conducted at a nominal loading rate of 10−2 MPa·m1/2/s using each of the aforementioned first three methods. The dynamic tests were conducted at loading rates in the range 100 to 104 MPa·m1/2/s using both servo-controlled and impact loading of three-point bend specimens. The results from the various static test methods are in good agreement. However, there is a clear effect of both specimen size and crack orientation on the measured static fracture toughness. The results from the dynamic tests show some evidence of a rate effect on fracture toughness as well as the same orientation dependence as the results from the static tests, but no specimen size dependence was evident.
Rock Permeability or Hydraulic Conductivity—An Overview
Authors: Sowers GF
Published: March 2009

The water transmission characteristics of rock formations are far more variable than those of most soils. The flow conduits include (1) primary porosity, the voids between mineral grains or fragments; (2) genetic porosity, voids which developed within the rock during its formation; and (3) secondary porosity, the joints, shear zones, and other cracks that formed subsequent to deposition. The porosity changes over time as the voids both fill up and become enlarged.

The flow patterns are complex, with tortuous paths between the different forms of porosity. Laminar and turbulent flow occur simultaneously, depending on void size and energy gradients. The flow can be characterized by a variable pseudopermeability coefficient, kp, in the expression q = kpiNA, where N varies from 1 for laminar flow to 0.5 for turbulent flow. Laboratory tests are useless unless the sample size is an order of magnitude larger than the secondary porosity spacing. Field measurements in bore holes or an evaluation of subregional discharge is necessary for making a realistic evaluation of kp of rock aquifers. There are likely to be large variations in kp depending on location, time, and changes in the groundwater environment.
Permeability of Soils Using Contaminated Permeant
Authors: Gordon BB , Forrest M
Published: March 2009

This paper describes two laboratory permeability testing programs involving the use of contaminated fluids as permeants. The first program involved the use of an alkaline permeant, and in the second program, an acidic permeant was used. Contaminated permeants were used in order to model field conditions anticipated in mining projects. Permeability depends on the properties of both the porous media and the permeant, whereas intrinsic permeability depends only on the void space of the porous material. The chemical and physical properties of the permeants were different from those of distilled water, which is normally used as a permeant. Therefore, the permeability of soils using contaminated permeants should not be expected to be the same as for a distilled water permeant. The equipment, development, and test methodology and results are discussed in this paper.
Acoustic Emission Signatures of Various Rock Types in Unconfined Compression
Authors: Boyce GM , McCabe WM , Koerner RM
Published: March 2009

An investigation of ten rock types in unconfined compression has led to four distinct types of stress versus acoustic emission response curves, that is, signatures. These are the originally proposed Mogi type, and three variations of this generalized behavior, that is, unstable, dense, and dense unstable types. They have been correlated to conceptual ideas on brittle rock behavior. Frequency analysis on all rock types at each stage of the various stress ranges has also been performed. Trends in peak frequency shifting are presented with implications as to the use of this information.
Subacute Toxicity Testing with Young Birds: Response in Relation to Age and Intertest Variability of LC50 Estimates
Authors: Hill EF , Camardese MB
Published: March 2009

The variability in toxic response of Japanese quail (Coturnix coturnix japonica) to a standardized 5-day subacute feeding trial was studied while age was increased at weekly intervals from 1 to 21 days and at different times with 14-day-old birds. The objectives were to identify the strengths and limitations of this subacute toxicity protocol and to provide possible explanations for differences in response among the various classes of pesticides. The variables included the median lethal concentration (LC50), the dose-response slope, food consumption, mortality patterns, and procedures of preparing toxic diets. Carbamate, organophosphate, chlorinated hydrocarbon, and organic mercury compounds were represented. A total of 60 subacute tests were involved in this evaluation. The general conclusions of the study are as follows: (1) The basic protocol yields good within-laboratory reproducibility of results. (2) The LC50s increase as birds grow older, and the change was reasonably predictable between 7 and 21 days of age. (3) Monitoring of time-related response patterns, such as food consumption, onset and remission of overt toxicity, and mortality, is critical to the evaluation of potential hazard. (4) Different orders of toxicity may occur at different ages for an array of compounds, but differences do not appear to be large enough to seriously alter the interpretation. (5) For optimal comparisons, all testing should be conducted on birds of a single age.
Placental and Mammary Transfer of Polychlorinated and Polybrominated Biphenyls in the Mink and Ferret
Authors: Bleavins MR , Aulerich RJ , Ringer RK
Published: March 2009

The placental and mammary transfer of polychlorinated biphenyls (PCBs) and polybrominated biphenyls (PBBs) was measured in the mink and European ferret. In short-term studies, PCBs were found to cross the placenta more readily than PBBs. Transfer of PCBs was greater in the ferret than in the mink. In a longer term study of placental and mammary transfer, newborn mink kit concentrations of PCBs and PBBs were similar. However, by 2 weeks of age, PBB levels were significantly higher than PCB levels. Milk levels of PBB were determined to be four times those of PCB. For both compounds, the mother's milk was found to be the major route of offspring exposure, with placental transfer being much less consequential.
Skid Resistance Predictive Models for Asphaltic Concrete Surface Courses
Authors: Emery JJ , Lee MA , Kamel N
Published: March 2009

Skid resistance performance models for dense and open graded asphaltic concrete surface courses are presented. Previous studies for dense graded mixes and high traffic volumes resulted in a predictive linear model for the skid number (SN) at 100 km/h (60 mph) (SN100) in terms of known aggregate and mix parameters and available traffic data. However, the SN100 does approach a constant level requiring a rational function to describe traffic influences. Further work has confirmed the overall importance of mix designs in achieving desired skid resistance with accumulated traffic influences, particularly in preventing coarse aggregate immersion due to traffic compaction. High stability mixes (all steel slag, blast furnace slag, or traprock, for instance) have proven most suitable, and coarse aggregate factors such as polished stone value and aggregate abrasion value are of secondary importance once adequate levels are provided. Using a wider range of test sections, improved predictive models have been developed for various traffic volumes and surface types. Full details on model development are given.
Tires – Roads – Rainfall – Vehicles: The Traction Connection
Authors: Veith AG
Published: March 2009

Meaningful assessment of tire wet traction performance requires an understanding of the tire use environment. The important factors are tires, rainfall conditions, roads, vehicles, and vehicle operation. Analysis shows that certain combinations of these factors are frequently associated with loss of control or skidding.

Tire performance (for wet traction) must be assessed under test conditions that closely duplicate certain critical pavement texture, speed, and water depth conditions. Under such worst-possible-case test conditions, an evaluation of tire performance is obtained where the motorist needs the greatest margin of traction reserve. If tires are evaluated at combinations of speed, pavement texture, and water depth that do not approximate the worst-possible-case set of factors, ambiguous or outright misleading tire performance appraisals may be made.

Based upon the results of an ongoing research and development traction program conducted according to these guidelines and upon certain literature sources, important tire design features are discussed vis-a-vis wet traction performance. The influence of construction features, tread compound, and tread pattern on wet traction is discussed as well as how these interact with certain external-to-tire factors.
Chemorheological Characterization of B-Stage Printed Wiring Board Resins
Authors: Tung CM , Dynes PJ
Published: March 2009

High-performance liquid chromatography (HPLC), gel permeation chromatography (GPC), dynamic mechanical analysis, and differential scanning calorimetry (DSC) have been used to characterize printed wiring board B-stage FR-4 epoxy resins. These techniques demonstrate a capability for fingerprinting the formulations and their thermal and rheological behavior. The relation between gelation and viscoelastic properties has also been examined. The results reveal a new and reproducible method of detecting the onset of gelation. The merit of each technique as a quick quality-control method is evaluated.
ASTM Committee E-36 Activities in Standards Development for Laboratory Evaluation and Accreditation
Authors: Berman GA
Published: March 2009

Accreditation is a formal determination and recognition that a laboratory has the capability to carry out specific activities. It is conferred by an accreditor following an assessment of a laboratory against applicable criteria. Since its formation in 1973, ASTM Committee E-36 on Criteria for the Evaluation of Testing and Inspection Agencies has been actively working to develop consensus criteria that could be used by others to evaluate and accredit laboratories. This paper highlights the activities, accomplishments, and future plans of Committee E-36 in the development of standards for laboratory evaluation and accreditation.
An Industry Approach to Laboratory Quality Assurance and Accreditation Programs
Authors: Fargo HE
Published: March 2009

A computerized approach to the massive record-keeping involved in a modern laboratory quality assurance program is described, with the Technical Center of Owens-Corning Fiberglas Corporation being used as an example.
The U.S. Army Corps of Engineers Laboratory Evaluation Program
Authors: Scanlon JM , Lamond JF
Published: March 2009

The U.S. Army Corps of Engineers has been evaluating contractor quality control laboratories, commercial laboratories being used by either the corps of engineers or its contractors, and government quality assurance laboratories for a quarter of a century. All of the corps division laboratories (New England, Ohio River, South Atlantic, Missouri River, Southwest, North Pacific, South Pacific, and the Waterways Experiment Station, acting as the division laboratory for the Lower Mississippi Valley Division) are evaluated by the Cement and Concrete Reference Laboratory sponsored by ASTM Committees C-1 on Cement and C-9 on Concrete and Concrete Aggregates and located at the National Bureau of Standards. In turn, representatives of these division laboratories evaluate the above-mentioned laboratories being used by construction contractors for quality control at corps projects. In addition, corps government quality assurance laboratories normally located at project sites are evaluated to verify that the procedures being used by government technicians and engineers comply with the specified standards. The Corps of Engineers Laboratory Evaluation Program does not certify; it only evaluates to verify that the capability exists, that the laboratory employees know how to perform, and that the necessary facilities and laboratory equipment are available to permit the performance of the tests and inspections correctly.
Developments in Australia and New Zealand Laboratory Evaluation Criteria
Authors: Garside JH , Gilmour JA
Published: March 2009

Laboratory accreditation on a national scale was first developed in Australia in 1947 and subsequently adopted in neighboring New Zealand in 1972. Broad statements of basic criteria for accreditation have remained constant ever since, but the interpretation and implementation of those criteria are evolving processes. Criteria are developed by consensus procedures to meet the needs of new fields of testing, new test methods, new measuring equipment, and new technology in both the laboratory and in industry. The basic approach to laboratory assessment by a process of peer review does not change, but as criteria develop the exact nature of the assessment procedure varies to accommodate that development.
Apparatus and Techniques for Static Triaxial Testing of Ballast
Authors: Alva-Hurtado JE , McMahon DR , Stewart HE
Published: March 2009

Railroad tracks are constructed on a layer of ballast overlying the roadbed subgrade. The ballast is a coarse-aggregate-sized, noncohesive, granular material with angular particles and usually with a uniform gradation.

In order to evaluate the geotechnical performance of railroad tracks, representative stress-strain-volume change and strength properties of the ballast are needed. Because ballast consists primarily of large [up to 76.2 mm (3-in.)] angular particles, conventional triaxial testing equipment is not appropriate. Therefore a large triaxial cell was designed and constructed. The apparatus used in the static ballast testing, and the sample preparation techniques developed, are presented.

Triaxial compression test results on the granite ballast for two different density states are shown. Mohr-Coulomb strength parameters are presented, and the typical stress-strain-volume change behavior is shown. The hyperbolic parameters calculated from the static tests are also shown.

The static test results using the new apparatus and sample preparation techniques indicate that railroad ballast possesses many characteristics common to granular materials.
Lateral Stress Measurements in Direct Simple Shear Device
Authors: Dyvik R , Zimmie TF , Floess CHL
Published: March 2009

Monitoring lateral stresses in a soil specimen during monotonic or cyclic shear tests significantly increases the amount of information obtained from these tests. A technique is described for interpreting lateral stress data during consolidation (the initial phase of either type of shear test) and determining the lateral stress level at the start of the shear test. In addition, the coefficient of lateral earth pressure at rest (K0) is determined.

The Norwegian Geotechnical Institute (NGI) Direct Simple Shear Device was used in this study. Lateral stress measurements were made with calibrated wire-reinforced membranes (acting as strain gages).

Two undisturbed samples of soft marine clay were investigated: a Gulf of Mexico and a Gulf of Alaska sample. The samples were obtained from a depth of about one metre below the sea floor. Large vertical specimen strains were encountered even though the applied consolidation stresses were small (a maximum vertical stress of 0.518 kg/cm2). The technique described includes methods for eliminating possible sources of substantial error at these low stress levels. The values of K0 as determined from the lateral stress measurements agree well with values determined indirectly.
A General Time-Related Soil Friction Increase Phenomenon
Authors: Schmertmann JH
Published: March 2009

Various laboratory treatments of clay specimens produced an increase in the frictional component of their ability to mobilize shear resistance. These treatments included compression after isotropic normal consolidation, compression after isotropic overconsolidation, anisotropic normal consolidation, chemically induced dispersion, changing pore fluid, decreasing rate-of-strain, increasing time for secondary compression, and allowing time for creep. The paper shows how increasing clay fabric dispersion in these treatments relates directly to an increased friction capability. The author then suggests that the dispersion shifts the external shear load to stiffer and stronger aggregates of particles in the fabric. This produces a stiffer and stronger clay due to its increased frictional capability. The practical aspects of this behavior include a better understanding of various laboratory specimen aging effects such as increasing modulus and the quasi-preconsolidation effect, recognizing it as a frictional and not a bonding behavior, and the desirability of including such behavior in the laboratory or computer simulation of in situ performance.
Stress Path Tests with Controlled Rotation of Principal Stress Directions
Authors: Arthur JRF , Bekenstein S , Germaine JT , Ladd CC
Published: March 2009

University College London (UCL) has developed a new flexible boundary plane strain shear apparatus for investigating stress-strain-strength anisotropy in sands. Called the Directional Shear Cell (DSC), it has the unique capability of controlling the major principal stress direction by varying the normal stress and shear stress acting on four faces of a cubical sample constrained between two rigid end plattens. The paper describes the device and its use, and presents results from a Massachusetts Institute of Technology (MIT) test program run on dense and loose Leighton Buzzard Sand to independently evaluate the device and for comparison with data obtained at UCL to investigate the effects of induced anisotropy due to prestraining. The DSC has now been used to measure inherent anisotropy in loose sand. These data are presented and MIT's progress in modifying the DSC to enable K0 consolidated-undrained testing of soft clays is described.
Borehole Shear Test in Geotechnical Investigations
Authors: Lutenegger AJ , Hallberg GR
Published: March 2009

The concept of Borehole Shear presents a unique alternative in shear strength testing of soil and rock in that tests may be conducted rapidly on the sides of the hole on relatively undisturbed material; therefore the inherent problems associated with obtaining equivalent information from laboratory tests are eliminated. In contrast to other methods of measuring in situ shear strength (that is, vane shear, cone penetrometer and pressuremeter) the Borehole Shear Test (BST) and Rock Borehold Shear Test (RBST) give discrete values of friction angle and cohesion; therefore more complete analyses may be made for such fundamental problems as bearing capacity and slope stability. In the past the BST has been considered a drained test and the effective parameters φ' and c' have been reported. This may not always be the case.

The general use, operation, assumptions, and problems of the test are examined and examples of the interpretation of results are given. Because of the time, economics, and accuracy of this method, the technique of Borehole Shear should see increased use in future in situ geotechnical testing.
Fatigue Fracture Micromechanisms in Poly(Methyl Methacrylate) of Broad Molecular Weight Distribution
Authors: Janiszewski J , Hertzberg RW , Manson JA
Published: March 2009

Scanning electron microscopy was used to examine the fatigue fracture surfaces of poly(methyl methacrylate) of varying molecular weight (MW) and molecular weight distribution. The specimens had been synthesized to incorporate various porportions of high- and low-MW tails in high, medium, and low-MW matrixes. In specimens with a high-MW matrix, increased proportions of low-MW additions resulted in higher fatigue crack growth rates and a gradual shift in the appearance of the fracture surface toward that of a low-MW matrix specimen with a small addition of a high-MW specie. Crack advance was continuous, with fatigue striation widths corresponding to the macroscopically measured growth increment associated with each loading cycle. In low-MW matrixes, addition of medium- and high-MW species resulted in attenuated crack growth rates and resulting longer life. With less than 2 percent of the medium- and high-MW species, crack advance was by a discontinuous mode with each growth increment equal to the size of the plastic zone at the crack tip. At high ΔK levels, discontinuous growth bands took on a scalloped appearance while maintaining a second power dependence between bandwidth and ΔK.
An Experimental Investigation of Creep Crack Growth in IN100
Authors: Donath RC , Nicholas T , Fu LS
Published: March 2009

Sustained load crack growth in IN100 at 732°C (1350°F) is studied using two specimen geometries, a standard compact tension specimen, and a radially crack ring loaded in tension. The effects of specimen thickness on the growth rate are investigated covering a range from 5.6 mm to 18.3 mm (0.22 to 0.72 in.) in thickness. Only the thinnest specimens show a crack growth rate which is lower than that obtained from all of the other thickness specimens. Stress-intensity factor, net section stress, and the C*-integral were investigated as possible crack growth rate correlating parameters. The concept of an “effective” crack length determined from specimen compliance measurements is introduced as a measure of crack length for severely tunneled crack front geometries. Neither net section stress nor C* is found to be acceptable as a crack growth parameter based on data from both test geometries. Although K provides fair correlation, the phenomenology of creep crack growth prevents its description adequately with only a single parameter. In particular, the crack growth rate is observed to decrease from an initially higher value to a “steady state” rate for constant values for any of the correlating parameters investigated.
Fracture Behavior of a Thick-Section Graphite/Epoxy Composite
Authors: Shih TT , Logsdon WA
Published: March 2009

In order to explore the possibility of utilizing composites as structural materials for generator retaining rings, the fracture behavior of an experimental thick-section [54 mm (2.125 in.)] graphite/epoxy composite was examined. Rectangular bend bar specimens of various cross-sectional dimensions were tested in three-point bending to determine the shear strength of the composite. Edge-notch-bend and center-notched-tension specimens with various notch depths were used to determine the fracture toughness of the composite. These tests served to permit an evaluation of the applicability of linear elastic fracture mechanics (LEFM) to composite materials in general and thick-section composites in particular. Results show that (1) LEFM is not directly applicable to thick-section composites with cracks perpendicular to the fiber orientation; (2) the test composite is insensitive to cracks in a plane perpendicular to the fibers, and the load-carrying capability can be calculated based on net section considerations; and (3) the failure mode of the test composite under three-point bending is interply shear failure. The interply shear strength equaled 24.6 MPa (3.5 ksi).
Modified Leach Test Incorporating an Elutriation Step for the Evaluation of Metal Sludges
Authors: Penland JL , Steward FA , Lancy LE
Published: March 2009

This study is limited to the evaluation of the toxic metal released from metal finishing sludges, combustion ashes, and the solid residuals from atmospheric dust collection systems in a landfill. When leach testing these wastes to establish the potential magnitude of the leachable metals, it has been found that the solid waste also usually contains readily soluble inorganic salts that could affect the leach results. The sludge cake usually contains only interstitial water. Evidently, the volume of the residual water and its salt content is a relatively small quantity. Slurries contain considerably more water, but the total salt content is still most often insignificant. The mix can be quite different if the treatment preceding the solids removal has utilized high-temperature processes, or has aimed to separate the solids by partial or total evaporation of the water. The ashes from combustion or the dust collected from atmospheric separation may not have been subjected to a water quench or washing; therefore, the soluble salts never have been separated. Depending on the volume of these salts when deposited in a landfill, they could by themselves cause a significant deterioration of the groundwater, surface waters, or the land. Therefore, a leach test method that would also reveal abnormal salt concentrations in the waste could fulfill an additional important function.

Washing the solids with water will remove most of these easily soluble solids from the waste, leading to a more dependable and repeatable test condition for a subsequent leach test. The wash waters, if separately collected and tested, will provide insight into the magnitude of the soluble salt content of the solids. Following this logic, a distinction can be made regarding the short-term leach results (wash water) and subsequently, based on a 24-h leach test, the long-term leachability of the solids.
Comprehensive Evaluation of the Abandoned LiPari Landfill
Authors: Gominger D , Lyon DA
Published: March 2009

The object of this program is to evaluate the present hazards at an abandoned landfill and to determine if an abatement program is feasible. This is the first time in the United States that such a program has been attempted. The site has been chosen for this type of study because of its size, the health hazard it presents to the residents, and the damage the leachate has done to the Chestnut Branch stream and Alcyon Lake. Testing of ambient air, groundwater, and fish flesh was conducted.
Development of Realistic Tests for Effects and Exposures of Solid Wastes
Authors: Daniels SL
Published: March 2009

Realistic standard methods are needed by both the regulatory agencies and the regulated communities to measure parameters for evaluating the degree of hazard of solid wastes and the degree of control of proper management techniques. Current regulations issued under the Resource Conservation and Recovery Act (RCRA) contain nonconsensus testing procedures for four characteristics of hazard and determinations of certain species in solid wastes.

Petition may be made for an equivalent testing method. The American Society for Testing and materials (ASTM) is currently developing an equivalent standard method to the U.S. Environmental Protection Agency (EPA) extraction procedure. Petition also may be made to exclude a specific waste produced at a particular facility if listing is found to be inappropriate. ASTM is presently active in providing standard methods for obtaining data for delisting. Standard methods also are needed for measuring the containment of wastes in tanks; the migration of constituents from impoundments, landfills, and landfarms; the destruction and removal efficiency in incineration processes; and the extent of conversion of hazardous constituents in physical, chemical, and biological treatment processes. Demonstration of equivalent performance for these processes for storage, treatment, and disposal of solid wastes using standard methods is a third area of ASTM involvement.

There are two parallel activities involving standard methods: the development of realistic standard methods for measuring effects and exposures of solid wastes; and the evaluation of reproducible results to establish regulatory limits on hazardous constituents and performance guidelines for waste management facilities. The development of realistic tests for effects and exposures of solid wastes is within the province of ASTM. Such tests must also include consideration of toxicity, partition, and fate of hazardous constituents. The evaluation of results is the joint responsibility of the regulatory agency and the regulated community.
Titanium Alloys for Biomaterial Application: An Overview
Authors: Bannon BP , Mild EE
Published: March 2009

Titanium and its alloys have been commercially available for over three decades. Its high strength-to-weight ratio plus its resistance to corrosion were recognized early and utilized by the aerospace and chemical industries, as well as by the medical profession. The benefits of corrosion resistance, biocompatibility, strength, and the ability to be incorporated by knitting bone make titanium a strong technical choice for use in surgery. In addition, the long-range availability of the metal and geopolitical stability of the nations where it is found make titanium a cost-effective implant material. The capacity of the titanium industry can be significantly increased within 18 months, and the industry currently has the capability and expertise to perform thermomechanical processing of titanium for implant manufacture.
A Method for Quantifying Stiffness Parameters of Titanium Alloy Femoral Stems and Cobalt-Chrome Alloy Prostheses
Authors: Espiritu ET , Rao S , Sew Hoy AL , Clarke IC , Sarmiento A
Published: March 2009

Seven Ti-6Al-4V femoral prostheses were compared with a conventional Charnley type of a cobalt-based alloy. Structural stiffness criteria for anteroposterior, mediolateral, and torsional loadings were considered and compared. The stems were replicated and sectioned at 10-mm increments, the cross-sectional outlines were digitized, and the stiffness criteria were calculated. Although Ti-6Al-4V was the more flexible alloy, some titanium alloy prostheses were stiffer than the Charnley type—up to approximately 70 percent greater in bending and 20 percent in torsion. In contrast, other titanium alloy stems had only 30 to 90 percent of the Charnley stiffness criteria. These data for the first time provide a simple means for the orthopedic surgeon to determine whether his stem of choice is comparable to the well-established Charnley hip or whether, depending on his perception, he wants a stiffer or more flexible one.
Comparison of the Fatigue Strength of Femoral Prosthesis Stems Made of Forged Ti-Al-V and Cobalt-Base Alloys
Authors: Semlitsch MF , Panic B , Weber H , Schoen R
Published: March 2009

No breakage of femoral prosthesis stems made of hot-forged cobalt-base or titanium-base alloys has been reported since 1972, in spite of their being loosened and severely overstressed. The minimum requirements imposed on fracture-resistant femoral prosthesis stems were established in laboratory tests and studies lasting several years. The results of these time-consuming and costly efforts have been confirmed by the nonoccurrence of fatigue fractures in more than 350 000 original Mueller and Weber hip joint prostheses with stems made of hot-forged, high-strength Co-Ni-Cr-Mo Protasul-10 alloy, one of the future-oriented alloys used for biocompatible and highly stressed long-term implants. Straight-stem hip prostheses made of hot-forged Ti-Al-V alloy in combination with ceramic Biolox ball heads give promising results, as has been demonstrated by extensive laboratory tests. This must be further confirmed, however, in long-term field studies.
Investigation of Surfaces of Retrieved Endosseous Dental Implants of Commercially Pure Titanium
Authors: Brunski JB , Moccia AF , Pollack SR , Korostoff E , Trachtenberg D
Published: March 2009

Previous work has shown that the interfacial tissue response to pure titanium endosseous blade-vent dental implants in dogs can be influenced strongly by the biomechanical use of the implant. The surfaces of all 16 implants retrieved from our previous study were examined in an effort to evaluate (1) the response of the implant biomaterial to in vivo conditions and (2) the nature of any tissues which attached to implant surfaces. Implants were implanted for two, four, six and twelve months.

No evidence of corrosion or release of titanium in adjacent tissues was observed. Implants did show bone and epithelial tissue attachment to the surfaces, but the quantity of such tissues was usually very small. Although functional versus nonfunctional implants in our previous research produced completely different interfaces, as seen in histology done after removal of implants from the tissues, the present work revealed no correlation between these interface structures and the tissue remnants which were scattered over tiny portions of the implant surface area.

While the data from this study indicate the corrosion resistance of pure titanium in a dental implant application, the implant material plus several additional factors must be considered together in interpreting the total interfacial tissue response to a dental implant.
Cartilage and Bone Ingrowth into Porous Titanium Implants
Authors: Nelson DD , Rubash HE , Mears DC
Published: March 2009

Cultured lapine articular chondrocytes were transplanted onto porous Ti-6Al-4V alloy and placed into osteochondral defects of 26 rabbit medial femoral condyles. At four, eight, and twelve weeks, the surface of porous titanium with a cell culture implant was compared with the animal's control knee, which had not received the cultured chondrocytes. Histologic examination of the articular surface revealed chondrocytes with metachromatic ground substance in 35 percent of the experimental knees. In the remaining 65 percent, either thick fibrous tissue or fibrocartilage was evident. The control knees revealed dense fibrous tissue. Thus, cultured chondrocytes can be grown on a porous titanium surface in vivo. However, the histologic appearance is not that of normal articular chondrocytes.
Application of Four-Point Ring-Twist Test for Determining Shear Modulus of Filamentary Composites
Authors: Greszczuk LB
Published: March 2009

A new test technique for measuring the shear moduli of isotropic and composite materials is described. The test technique employs circular rings subjected to out-of-plane four-point loading: four forces of equal magnitude, two upward at 0 and 180 deg and two downward at 90 and 270 deg. The pertinent equation relating ring deformation to applied loading, ring-section properties, and elastic properties is given. It is shown that by selecting appropriate specimen geometry, the deflection of the ring subjected to four-point loading is governed primarily by shear deformations. The reliability and accuracy of the test method are demonstrated by conducting tests on metallic rings as well as on rings made of various composite materials. Room as well as elevated-temperature shear-moduli data are measured using the ring tests. The results from the four-point ring-twist tests are compared with data presented in the literature. The test is simple and fast, with no requirement for elaborate instrumentation or setup. Moreover, the test is applicable for measuring the shear moduli at room temperature, cryogenic temperatures, and elevated temperatures.
Low-Velocity Impact Tests on Fibrous Composite Sandwich Structures
Authors: Sharma AV
Published: March 2009

An experimental investigation was conducted to assess the damage tolerance of composite sandwich structures subjected to low-velocity projectile impact. Sandwich-type specimens fabricated with graphite/epoxy materials having laminate configurations such as (±45,04)s, (±45,90,0)s, and (90, ±45,0)s were tested. Impact tests were performed at low energy levels to assess the strength degradation of composite laminates when compared with their ultimate strengths. Low-energy projectile impact was considered to simulate typically the damage caused by runway debris and the accidental dropping of hand tools during servicing and other similar objects on secondary aircraft structures fabricated with composites. The preload and impact energy combination necessary to cause catastrophic failure was determined. The residual strength of specimens that survived the impact damage was also measured.

Based on the experimental results, a faired curve indicating the lower bound of the failure threshold for each of the laminate configurations tested in compression and tension as a function of the projectile impact energy is shown. Further, the strength degradation due to impact is found to be dependent on the laminate configuration and the fiber/matrix combination.
Mechanical Characterization of PMR-15 Graphite/Polyimide Bolted Joints
Authors: Wilson DW , Pipes RB , Riegner D , Webster J
Published: March 2009

Design-allowable data characterizing the static strength and viscoelastic performance of PMR-15/Celion 6000 graphite/polyimide composite bolted joints are presented. Two laminate configurations in the [0i/±45j/90k]ns family, one-fiber-dominated and one matrix-dominated, were studied. Temperature-dependent strength characteristics were measured over the 21 to 315°C temperature range for several joint geometries. Effects of strain rate on strength and failure mode behavior were assessed at room temperature for rates ranging between 0.002 and 1.00 s−1. Creep behavior was examined for the case of bearing deformations at temperatures of 21 and 177°C. Ultrasonic inspection techniques were used to assure material integrity and to verify post test damage and failure mode.
Sulfur Measurement in Liquid and Gaseous Alternative Fuels
Authors: Kimbell CL
Published: March 2009

This paper describes sampling systems, analyzers, and analysis procedures developed for measurement of the sulfur content in alternative fuels. Alternative fuels are here defined as any fuel other than coal, oil, natural gas, or liquid petroleum gas. The object of the work described here is to determine the hydrogen sulfide (H2S) and total sulfur content of various fuels. Particular emphasis is placed on determining whether substances present in the alternative fuel might interfere in sulfur measurement, causing loss of accuracy when a test method used to measure sulfur in conventional fuels is applied to alternative fuels.

The equipment described in this study consists of a total sulfur analyzer with a pyrolysis furnace, used in the reductive mode, to convert all sulfurs to H2S. An H2S analyzer operating on the principle of colorimetric change of a lead-acetate-sensing surface, with rateometric readout, is used for H2S analysis. When coupled with the hydrogenolysis furnace, a readout in terms of total sulfur results.

Successful testing of raw shale oil, as well as of refined products from shale oil, was accomplished. The results correlate well with X-ray analysis at high sulfur concentrations in raw shale oil and for refined products of Jet A turbine fuel.

The accuracy between laboratories was within 40 ppb.
Heating Values of Natural Gas and Its Components: Conversion of Values to Measurement Bases and Calculation of Mixtures
Authors: Armstrong GT , Jobe TL
Published: March 2009

The standard enthalpies of combustion of the pure hydrocarbons C1 to C6 at 298.15 K and 101.325 kPa, selected from the literature, with reference to a more detailed document, are used to derive heating values for the ideal gas and the real gas on molar, mass, and volumetric bases at five reference conditions, involving other temperatures and pressures. The values can be obtained at both dry and water-saturated conditions. The second virial coefficients and their first derivatives are used to calculate the effects of nonideality. Procedures are given and illustrated for calculating the heating values of mixtures from the composition, and the data are given for the pure compounds. The relationships between the quantities presented in the tables are illustrated by charts. A procedure is given for estimating the uncertainties of the calculated results.
Tissue-Culture Biocompatibility Testing Program
Authors: Johnson HJ , Northup SJ
Published: March 2009

Four methods of in vitro biocompatibility screening using L-929 mouse fibroblast cells are discussed, namely, the fluid medium, agar diffusion, flask dilution, and flask dilution extraction methods. The range of test methods allows toxicity screening of both solid and liquid specimens and has been shown to provide good agreement with and better sensitivity than the United States Pharmacopeia (USP) rabbit muscle implantation assay. Approximately 2000 specimens are subjected to such in vitro evaluations annually at our facility for evaluating stability studies, component changes, formulations, and manufacturing processes. A scale of 0 to 4+ is used to indicate the extent of cellular damage providing a quantitation of toxic response.
Bird Dispersal Recordings: An Overview
Authors: Schmidt RH , Johnson RJ
Published: March 2009

Bird damage control often involves dispersing birds from areas where they cause problems. Dispersal techniques have been used at airfields, rural and urban bird roosts, livestock facilities, fruit orchards, grain fields, and other locations. Certain avian vocalizations have evolved as alarm or distress calls, and these calls can be exploited as a means of dispersing birds. The behavioral response to such calls, however, varies. Certain species may disperse with the appropriate call, whereas others show little or no reaction. The efficacy of this technique is not well documented at present, but its potential for development as a management tool seems great.

Visual warning signals may increase the effectiveness of bird dispersal recordings by decreasing the habituation rate, increasing realism, or decreasing the fright threshold of the birds causing problems, or by a combination of these factors. Habitat manipulation, which reduces the attractiveness of an area to birds, complements dispersal efforts. It appears that a combination of management techniques is the most effective strategy. In addition, pretreatment evaluation of the problem and situation plus records of field results are helpful parts of a dispersal effort.

Evolutionary, theoretical, and applied aspects of bird communication are discussed as they relate to bird dispersal, the repellency of recorded sounds, habituation rate, and effects of regional dialects. A review of the vocalization and hearing ranges of birds is included; this may help define the frequency and type of sounds most likely to disperse birds. The characteristics of recording and broadcasting equipment are detailed in relation to component selection, and suggestions are made for effective use. A section on field application of bird dispersal recordings provides guidelines for duration and spacing of playbacks and recommends using an integrated approach. Continued refinement of bird dispersal recordings and associated techniques can increase considerably our effectiveness in solving bird damage problems.