bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparison of Two Cobalt-Based Alloys for Use in Metal-On-Metal Hip Prostheses: Evaluation of the Wear Properties in a Simulator
Authors: St. John KR , Poggie RA , Zardiackas LD , Afflitto RM 
Published: March 2009

One of the areas of research for reducing the generation of wear debris from total joint replacements is the utilization of cobalt alloys that meet ASTM F 1537 for the production of metal on metal bearing pairs. The standard currently allows carbon contents to range between 0% and 0.35%. Some research on metal-on-metal hip bearings indicates that alloys with carbon content at the upper end of this range will yield bearing pairs with superior resistance to wear. The purpose of this study was to compare the wear resistance of components manufactured from high carbon (0.24%) and low carbon (0.06%) alloys when tested in a hip simulator.
Wear of the metal cups was measured by a gravimetric (weight loss) technique every 500 000 cycles to a total of 5 000 000 cycles. Wear of the metal heads was evaluated approximately every 1 500 000 cycles, to 5 000 000 cycles. Results of the study show a small difference in wear between the two alloys. After the initial wear-in period, the samples with the higher carbon content exhibited a significantly lower wear rate than those with the lower carbon content.
The Use of Local Approach to Fracture in Reactor Pressure Vessel Structural Integrity Assessment: Synthesis of a Cooperative Research Program Between EDF, CEA, Framatome and AEA Technology
Authors: Moinereau D , Frund JM , Brochar J , Valeta MP , Marini B , Joly P , Guichard D , Bhandari S , Sherry A , France C , Sanderson DJ 
Published: March 2009

A cooperative research program on the field of the local approach to cleavage fracture applied to reactor pressure vessels is conducted between Electricité de France, CEA, Framatome and AEA Technology. The purpose of this program is to have a better knowledge of this kind of approach for reactor pressure vessels fracture mechanics integrity assessments regarding the risk of brittle fracture. This program includes both an experimental part on the A508 C13 steel and numerous 2D and 3D numerical computations.
The identification of m and σu parameters of Beremin model (local approach to cleavage fracture) is studied on the A508 C13 steel using mechanical tests on axisymmetrical notched tensile specimens AE2. The tests are performed at several temperatures (-100 °C, -130 °C and -170 °C) by three laboratories (EDF, CEA and AEA Technology). There are 120 specimens tested in total. The experimental results from different laboratories are compared and analyzed, the effect of temperature on m and σu parameters of Beremin model is discussed and a standard procedure to identify these parameters is proposed.
Within the framework of this program, numerous two-dimensional numerical calculations using the Beremin model have been performed by different partners on several cracked specimens (CT specimen, cladded vessels with flaws in cladding or in base metal under thermal loading…). Some comparisons between finite element programs (Aster, Castem 2000, Systus and Abaqus) are made on reference specimens in order to evaluate and validate finite element programs in the field of local approach to cleavage fracture. These comparisons show a rather good agreement on main parameters, notably on Weibull stress σw calculation for mechanical or thermal loading.
The “shallow flaw effect” is examined from these computations. The effect of the “a/W” ratio on the probability of cleavage failure is clearly underlined with the Beremin model using the “Weibull stress σw versus Stress intensity factor KJ” curves. Significant differences between cracked specimens are observed, related to the “a/W” ratio : for a given level of the stress intensity factor KJ, the probability of cleavage failure increases with increasing values of flaw depth. These results show that the Beremin model is able to predict an influence of crack tip constraint on fracture toughness.
Finally, first three-dimensional applications of the Beremin model are presented regarding the interpretation of large-scale tests performed on cladded specimens containing subclad flaws.
Structural Loading and Fatigue Failure Analysis of Off-Road Bicycle Components
Authors: DeLorenzo DS , Hull ML 
Published: March 2009

The research described herein accomplished the goals of off-road bicycle load quantification and fatigue life prediction. A fully-instrumented test bicycle was equipped with dynamometers at the pedals, handlebars, and hubs to measure all in-plane structural loads acting through points of contact between the bicycle and both the rider and the ground. A portable data acquisition system carried by the standing rider allowed, for the first time, this loading information to be collected during extended off-road testing. In all, seven experienced riders rode a downhill trail test section with the test bicycle in both front-suspension and full-suspension configurations.
The load histories were used to quantitatively describe the load components through the computation of means, standard deviations, amplitude probability density functions, and power spectral density functions. For the standing position, the coefficients of determination for the load components normal to the ground were greater than 1.35 for handlebar forces and 0.3 and 0.5-0.6 for the pedal and hub forces respectively. Thus the relative contribution of the dynamic loading was much greater than the static loading at the handlebars but less so at the pedals and hubs. As indicated by the rainflow count, high amplitude loading was developed approaching 3 and 5 times the weight of the test subjects at the front and rear wheels respectively. The power spectral densities showed that energy was concentrated in the band 0–50 Hz.
To illustrate the usefulness of the loading data, the load history at the pedal was used to determine the corresponding stresses at the pedal spindle hot-spot location. To predict the fatigue life, the resulting stress cycles were processed by use of a rainflow counting algorithm. Cumulative damage was quantified through Miner's linear damage rule used in conjunction with the nominal S-N method. The stress cycles were also used to develop a fatigue testing protocol for verifying analytical predictions of fatigue life.
Fatigue Life Predicition of Resistance Spot Welds Under Variable Amplitude Loads
Authors: Pan N , Sheppard SD , Widmann JM 
Published: March 2009

The work presented here builds on the practical and effective spot weld fatigue life prediction method, the structural stress method (SSM), that was developed recently [1]. Constant amplitude loading tests for various spot weld joint configurations have been conducted and the SSM has been shown to accurately predict fatigue life [1].
In this paper, a variable amplitude fatigue life prediction method based on the SSM and Palmgren-Miner's rule is proposed. A test matrix was designed to study the fatigue behavior of spot welds under tensile shear loading conditions. Constant amplitude tests under various R-ratios were first performed to obtain necessary material constants. Variable amplitude tests were then performed. Experimental and finite element data are presented. The ability of the SSM to include load ratio effects and predict life for variable amplitude tests is illustrated.
Outflow Methods for Evaluating the Soil Hydraulic Functional Relationships Between NAPL Pressure and Saturation in Porous Media
Authors: Bali KM , Grismer ME , Hopmans JW 
Published: March 2009

Remediation and cleanup of petroleum product contaminated ground water often require modeling of fluid transport processes when immiscible liquid phases (e.g., water and oil) are present. Modeling of such multiphase transport systems requires knowledge of the functional relationships between fluid pressures, saturations, and permeabilities. We evaluated the applicability of the multistep outflow method used in soil science to determine these functions for two porous media (loam and sand) using Soltrol 130 and water as wetting fluids.
The analytical retention and permeability functions of van Genuchten (1980) and Mualem (1976) were used, with an inverse method that has been shown to be reliable in estimating water retention and unsaturated hydraulic conductivity in soils (Eching and Hopmans 1993), to estimate soil hydraulic function parameters for Soltrol 130 and water. The water and Soltrol 130 cumulative drainage as a function of time and the equilibrium saturations were used as input to a numerical model (MLSTPM) to optimize, through an inverse solution of the Richards equation, the parameters needed for the hydraulic functions.
Optimizations were carried out for saturation paths corresponding to monotonically decreasing wetting phase saturations only. The functional relationships between oil pressures, saturations, and permeabilities in Oso-Flaco fine sand were accurately predicted from the optimized water retention curve parameters based on scaling by the ratio of interfacial tensions. However, this scaling procedure was inadequate to predict oil hydraulic function parameters from those of water in Yolo loam.
Dual-Phase Vacuum Extraction Technology for Soil and Ground-Water Remediation: A Case Study
Authors: O'Melia BC , Parson DR 
Published: March 2009

Soil vapor extraction (SVE) has become a common, effective method to remediate soils contaminated by volatile organic compounds (VOCs). The technology induces a soil gas flow through the vadose zone, which extracts VOCs into the soil gas being extracted. The Dual-Phase Vacuum Extraction (DVE) system uses a high vacuum source to extract both soil gas and ground water from the same extraction well. The creation of a two-phase flow in the extraction piping eliminates the need for a separate pumping system for ground-water recovery. The high vacuum can also induce a higher recovery of ground water than typical downhole pumping methods can provide.
An Air Force Base (AFB) site, located in the United States, previously used an underground storage tank to contain waste solvents, primarily methylene chloride and perchloroethylene, from paint stripping and application operations prior to disposal. Leakage from the tank system resulted in subsurface soils and ground water with elevated levels of these chlorinated solvents. The soils at the site consist of silty clays and clayey silts with low permeabilities. The DVE system was pilot-tested to evaluate performances for site remediation.
Two extraction wells were tested separately. The average soil gas extraction rate per well was 1.05 m3 per minute with radius of influence of 10.7 m. For ground water, the average recovery rate per well was 3 L/min with a radius of influence of 23.2 m. These radii influences were significantly higher than those estimated for traditional soil vapor extraction or ground-water removal technologies. Removal rates ranged from 11.4 kg/day for an area with high levels of VOCs to 2.3 kg/day for an area with lower levels of VOCs.
Coastal Oceanographic Characteristics and Their Impact on Marine Effluent Biotoxicity Studies During The SEFLOE II Project
Authors: Commons DN , Proni JR , Fergen RE 
Published: March 2009

The Southeast Florida Outfall Experiment II (SEFLOE II) study was conducted at four ocean outfalls to determine the dispersion characteristics and biotoxicity of their effluent in the coastal ocean. The effluent from these facilities is secondary treated municipal wastewater. This paper deals with the impact of coastal oceanographic characteristics upon the biotoxicity aspect of the SEFLOE II study on data collected at the Broward County outfall.
During the study, whole effluent toxicity (WET) bioassays were compared to bioassays analyzed on samples taken from the outfall dispersion plumes. The ocean bioassays results were then evaluated along with contemporaneous current direction and speed data to determine initial and farfield dilutions and calculate Eularian and Lagrangian exposure impacts.
The bioassay comparison appears to indicate that standard WET methodology does not adequately take into consideration the substantial differences in dilution ratios and exposure times used in laboratory analyses with those experienced in actual environmental field conditions especially for ocean outfalls.
Actinide, Elemental, and Fission Product Measurements by ICPMS at the Savannah River Site
Authors: Tovo1 LL , Clymire JW , Boyce WT , Kinard WF 
Published: March 2009

A VG Elemental Inductively coupled plasma-mass spectrometer (ICPMS), PlasmaQuad 1 (PQ1) Model No. 4, installed in a radiological controlled hood, is used by the Savannah River Technology Center to provide non-routine mass measurements for environmental monitoring, waste tank characterization studies, isotope ratios for criticality determinations, and the measurement of elemental, fission product, and actinide mass distributions of the glass product from the Defense Waste Processing Facility (DWPF).
Modifications to improve instrument reliability, sample preparation, and data handling, as well as modifications to the laboratory that permit measurements in a radioactive environment, will be discussed. Based on our operating experience, two laboratory facilities are being prepared for additional instruments to operate in a radioactive environment. A separate instrument is being installed for non-radioactive measurements and method development.
Reducing Tool Wear When Machining Austenitic Stainless Steels
Authors: Magee JH , Kosa T 
Published: March 2009

Austenitic stainless steels are considered more difficult to machine than carbon steels due to their high work hardening rate, large spread between yield and ultimate tensile strength, high toughness and ductility, and low thermal conductivity. These characteristics can result in a built-up edge or excessive tool wear during machining, especially when the cutting speed is too high. The practical solution is to lower the cutting speed until tool life reaches an acceptable level. However, lower machining speed negatively impacts productivity. Thus, in order to overcome tool wear at relatively high machining speeds for these alloys, on-going research is being performed to improve cutting fluids, develop more wear-resistant tools, and to modify stainless steels to make them less likely to cause tool wear.
This paper discusses compositional modifications to the two most commonly machined austenitic stainless steels (Type 303 and 304) which reduced their susceptibility to tool wear, and allowed these grades to be machined at higher cutting speeds.
Assessing Chemical Data Quality for Risk Assessment Through Data Validation
Authors: Vitale RJ 
Published: March 2009

The chemical analytical data that are generated as part of every Superfund investigation are vital for the decisions that will be made regarding selection of a remedy and, ultimately, the future use of a site. Data validation is a process whereby laboratory data (and, to a limited extent, field data) are rigorously qualitatively and quantitatively scrutinized to determine the correctness of the results and to determine if the specified data quality objectives (DQOs) have been achieved. Data quality indicators are used as a gauge to determine if the quality of the data is adequate for the intended use.
Although data validation has become recognized as an important aspect in assessing data quality, a tendency has evolved to turn the validation process into a “checklist” exercise. A case study provides compelling evidence to avoid such approaches, which “short circuit” rigorous data validation. In the case study, rigorous validation of raw instrument output revealed analytical problems that had a significant impact on the risk assessment. These analytical problems were not identified during the initial checklist data validation approach.
Data Quality Objectives for Two Risk Assessments at Hanford
Authors: Lane NK , Clark SW , Tranbarger RK , Roeck FV 
Published: March 2009

The opportunity for innovative thinking prevails at the U.S. Department of Energy's Hanford Site in southeastern Washington state. Two projects, in particular, challenged risk assessment staff. They are: 1. A combined Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA)/Resource Conservation and Recovery Act (RCRA) risk assessment 2. Developing a risk assessment for a mixed-waste disposal facility.
The combined CERCLA/RCRA risk assessment involved establishing data quality objectives (DQO) either to meet clean closure for a RCRA treatment, storage and/or disposal facility (TSD) or (if the former was not possible) to conform to goals established for industrial land use for Hanford Past-Practice Strategy (HPPS) sites. Radionuclide analysis was reduced by 60 percent through the DQO process.
Developing a risk assessment for the RCRA TSD facility raised several issues. What is the source of information for the contaminants of concern? What are the scenarios for exposure? How will the short-term and long-term impacts be evaluated?
Evaluation of the Use of Substitution Methods to Represent Nondetect Data
Authors: Floit SB , Mahoney LA , Batey JC , Petroff DM 
Published: March 2009

One of the issues in quantitative human health risk assessments is the handling of nondetect data. Typically nondetect data are reported by the analytical laboratory as sample quantitation limits (SQLs) and qualified to indicate that the values were nondetect. Nondetect values, however, could actually fall anywhere within the range of zero to the SQL.
Four substitution methods for handling nondetect data were applied to a database of soil concentrations from a site to evaluate the impact on resulting constituent-specific 95 percent upper confidence limits (UCLs). The four methods utilized were: (1) one-half the SQL; (2) one-fifth the contract required quantitation limit (CRQL) (3) zero; and (4) the use of a random number generator to represent nondetect data with values ranging between zero and the SQL.
At low frequency of detections, the currently recommended USEPA Superfund approach of representing nondetect data with one-half the SQL was the least conservative method. As the frequency of detection increased, the resulting 95 percent UCLs for this method became more conservative (larger).
A Novel Method to Determine Mass Median Diameter and In-Flight Evaporation of Aerially Sprayed Droplets Deposited on Artificial Samplers at Ground Level
Authors: Sundaram A , Sundaram KMS 
Published: March 2009

An aqueous emulsion of permethrin containing a water-soluble red dye was applied at a dosage rate of 70 g of the active ingredient in 4.0 L per ha, using a Cessna 188B aircraft (equipped with 4 × AU3000 Micronair® atomizers), over a 400 m × 400 m spray block in Thessalon in northern Ontario, Canada. Spray mass recovery was assessed on glass plates at ground level and droplets were collected on Kromekote® cards. The stain sizes were grouped into different categories. The area containing the stains were excised and permethrin was extracted. The mass of permethrin present in the extract was determined by gas-liquid chromatography (GLC). The average mass per droplet in each size category was calculated. The mass (of permethrin) median diameter (DM.5) and volume median diameter (DV.5) at the spray release height were computed. The present method showed, for the first time in literature, the advantage of not having to use the conventional tedious procedures to determine spread factors to arrive at the DM.5 and DV.5 values.
The DM.5 was 113 μm both at spray release height and at ground level, and was identical to the volume median diameter (DV.5) at spray release height. The present study provided a method to determine the DV.5 at spray release height for that fraction of the spray cloud that deposited on the Kromekote cards at ground level.
The present study also provided information, for the first time, on the percentage decrease in droplet volume and droplet diameter due to evaporation in-flight. When the emitted droplet sizes increased gradually from 33 to 185 μm, evaporation in-flight decreased progressively resulting in droplet sizes of 16 to 181 μm at ground level. The percent decrease in droplet volume was 88.4 for the smallest droplet and 5% for the largest one. Correspondingly, the droplet diameter decreased from 51 to 1.7%, indicating that the small droplets evaporated to a greater extent than the large ones because of their large surface area to mass ratio.
Improvement of Initial Adhesion to Aluminum of Insulating Glass Polyurethane Sealants Using a Tertiary Amine Based Curing System
Authors: Hubin-Eschger PJ 
Published: March 2009

Hydroxylated polybutadiene based insulated glass sealants are well known to have a very low moisture vapor transmission rate and an excellent adhesion to glass and aluminum. Since the beginning of their industrial development, the best and most known and effective curing system for these sealants has been an organomercuric ester based catalyst.
The current and future pressure regarding ecological and toxicological issues will make this type of product increasingly difficult to use. This paper presents the results of work to develop other catalytic systems, which were obtained with the tertiary amine dimethylbenzylamine. The final improvement of initial adhesion to aluminum is obtained with the use of phenolic derivatives of coumarone indene.
The Effect of Artificial Weathering and Movement Accommodation Testing on Building Sealants
Authors: Beasley JL , Jenkins MR 
Published: March 2009

This paper describes the effect of an ultra violet radiation, heat and condensation artificial ageing procedure on the ability of a range of building sealants to survive a movement accommodation test based on the ISO 9047 test method. Sealants stored under standard laboratory conditions were also subjected to the movement accommodation test.
It is shown that sealants which initially pass the movement accommodation test will continue to pass after up to 24 weeks of exposure to the artificial weathering, or storage in standard conditions. Sealants that initially do not survive the movement test can improve their performance after exposure to artificial weathering or storage in standard conditions.
Tensile tests were carried out on sealants that survived the movement test and on static control specimens. It has been found that the movement test, and to a lesser extent the artificial weathering, can reduce the width of the test samples. It has also been found that the movement test can decrease the force produced by most one part sealants when extended to a width of 15mm, nominally 25% strain.
No relationship between changes in sample width or force at 15mm width and the ability to survive the movement test has been found.