bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of the Water Quality Significance of OP Pesticide Toxicity in Tributaries of Upper Newport Bay, Orange County, CA
Authors: Lee GF , Jones-Lee A , Taylor S 
Published: April 2008

Stormwater runoff in San Diego Creek, the primary tributary to Upper Newport Bay in Orange County, CA, has been found to be toxic to Ceriodaphnia and Mysidopsis with total acute 24 hr toxicities up to 16 acute toxic units (TUa). About half of this toxicity has been found to be due to the organophosphate (OP) pesticides diazinon and chlorpyrifos used in urban areas for structural termite and ant control, and lawn and garden pest control. The other half is due to unknown causes likely associated with the use of pesticides in commercial nurseries and agriculture. The non stormwater flow into Upper Newport Bay is non-toxic. Stormwater runoff events cause short-term pulses of toxic waters to enter this marine bay.
Studies on the fate of the toxic pulses of San Diego Creek water in Upper Newport Bay show that for many stormwater runoff events, the Creek freshwater forms a lens above the marine waters that is diluted by tidal mixing with the bay's marine waters. The regulatory issue that should be assessed is the water quality and ecological significance of the pulses of aquatic life toxicity that exist in the waters at the bottom of the freshwater lens where the Creek waters mix with the marine waters. For some stormwater runoff events, potentially toxic waters are present in a limited areal and volumetric extent in the bay for several days. It is unclear whether these toxic pulses of OP pesticides are significantly adverse to the beneficial uses of Upper Newport Bay because of their limited duration and the limited number/type of marine aquatic organisms that are exposed to toxic conditions associated with stormwater runoff events. Further studies need to be conducted to define the magnitude of the potential beneficial use impairment of bay waters due to this toxicity.
Evaluation of a Terrestrial Foodweb Model to Set Soil Cleanup Levels
Authors: Doctor PG , Gano KA , Lane NK 
Published: April 2008

The Washington State Department of Ecology (Ecology) is revising the Model Toxics Control Act (MTCA: WAC 173-340-7490 to 7494) to include terrestrial food pathways in an ecological risk evaluation and to set cleanup levels. One of the key provisions of the ecological risk assessment approach proposed by Ecology is a generic simplified “foodweb” model that would be used to set cleanup levels.
The terrestrial model is based on four feeding guilds and default species are the earthworm, shrew, vole, and robin. The use of a foodweb model implies that the results should in some way be descriptive of the ecosystem being evaluated. Any decision criterion (e.g., a benchmark or cleanup level) should be site-specific, and based on species present at the site. The default species are not representative of the fauna in the native shrub-steppe ecosystem of the Hanford Site. Therefore, the use of species not present at the site to set soil cleanup levels seems flawed. Alternative species for the four feeding guilds have been selected. Species specific exposure parameters were developed from the literature.
Using Ecological Site Scoping to Evaluate Contaminant Transport Pathways
Authors: Ryti RT , Kelly E 
Published: April 2008

Los Alamos National Laboratory (LANL) has developed an ecological screening evaluation process that emphasizes the development and testing of an ecological exposure and transport pathway site conceptual model. LANL developed this screening approach in partnership with personnel from the State of New Mexico regulatory authority (the New Mexico Environment Department or NMED).
A key part of the screening evaluation process is the completion of an innovative ecological scoping checklist. This checklist helps to (1) determine if complete pathways to ecological receptors exist; (2) determine how the impacted media should be aggregated spatially for screening, establishing the functional/operational boundaries of the assessment; and (3) gather information to develop the site conceptual model (SCM). The SCM includes contaminant sources, dominant transport pathways and exposure routes, and potential receptors. The scoping checklist consists of a series of questions and placeholders for field notes, which are intended to guide the risk assessor in developing the SCM, and provide the decision-makers with consistent information on receptors, potential transport pathways and potential exposure pathways. This paper summarizes the LANL/NMED scoping checklist and gives examples of its application at the LANL Environmental Restoration (ER) sites.
Risk Assessments and Hazardous Waste Cleanup in Indian Country: The Role of the Federal-Indian Trust Relationship
Authors: Tano ML 
Published: April 2008

Federal law, policy and court decisions demonstrate that a trust relationship exists between the federal government and Indian tribes; that the obligations thereunder attach to all executive agencies of the federal government; and that the performance of these obligations should be judged by the most exacting fiduciary standards. These fiduciary duties require, where a tribal or treaty asset has been harmed through the actions of the federal trustee, an absolute obligation to correct the harm. Thus, the use of risk ranking systems such as the Hazard Ranking System or the Department of Defense's Relative Risk Site Evaluation Framework, to determine if environmental cleanup is required is inappropriate. The author maintains risk analysis is more appropriately used to determine when and how such cleanup will proceed.
The author also argues that more research is required to develop metrics to evaluate the totemic, ceremonial aspects of trust assets such as salmon or religious sites; and the impact of the loss or impairment of the totem to the spiritual, emotional, mental and physical health and cohesiveness of the tribal society.
Cold Starting and Pumpability Studies in Modern Engines — Results from the ASTM D02.07C Low Temperature Engine Performance Task Force Activities: Cold Start Testing
Authors: Tseregounis S , De Paz EF , Girshick FW , Henderson KO , May CJ , Rhodes RB , Ying LH 
Published: April 2008

Cold start studies were conducted on 10 different engines (including duplicates of one type), and six different multigrade oils ranging from SAE 0W-30 to 25 W-30. As expected, the results showed that for all the engines, the minimum starting temperature decreased with decreasing winter viscosity grade. The 4.0L I-6 engine had the highest minimum start temperatures (MSTs) for all the oils, while the lowest MSTs were distributed over seven of the other eight engines tested. The difference in the starting characteristics of the 4.0L I-6 engine were attributed to the fact that this engine design was relatively old (early 1980s) compared to the rest of the engines in this program (1990s). Another interesting observation was that, excluding the 4.0L I-6 engine, there was no effect on the MSTs due to engine displacement, number of cylinders or configuration. This is contrary to older studies which showed that as number of cylinders increased, minimum starting temperatures decreased. Improved starting characteristics of these modern engines are attributed to improvements in engine technology.
An excellent correlation was observed between minimum start temperature and cold cranking simulator (CCS) viscosity for the modern engines. In addition, the CCS viscosity for these engines at the minimum start temperatures was 2 to 4 times higher than the present SAE J300 limits. In contrast, the MSTs for the older engine design (4.0L I-6) appear to follow the present CCS temperature and viscosity limits. The oil viscosity at the MST for the 4.0L I-6 engine was relatively constant (3,000 to 5,000 mPa-s) throughout the whole temperature range, while with the newer engines, limiting viscosity decreased with decreasing temperature (25,000 mPa-s at -19°C to 7,000 mPa-s at -37°C). This requirement for lower oil viscosities at lower temperatures is attributed to a need to compensate for increased internal engine friction with decreasing temperature.
Comparison of these results with those from the 1970s shows that the older engine design (4.0L I-6) follows a similar pattern (comparable CCS viscosities and no temperature effect) to the old 4- and 6-cylinder engines, while the newer engines parallel the results for older V-8s.
Comparison of the Environments of Transportation Vehicles: Results of Two Surveys
Authors: Dumyahn TS , Spengler JD , Burge HA , Muilenburg M 
Published: April 2008

Two surveys of commercial transportation environments were conducted. In the spring of 1994, environmental conditions on a variety of aircraft over 22 domestic routes were monitored. In 1996, an expanded survey of 27 travel segments was performed on Boeing 777 aircraft, interstate trains, interstate buses, short-distance commuter trains, and subways. A wide variety of environmental measurements were performed including standard Indoor Air Quality (IAQ) parameters of temperature, relative humidity and carbon dioxide (CO2). Aircraft cabin air pressure was continuously measured. Contaminants including carbon monoxide, particles, and volatile organic compounds (VOC) were monitored or sampled. Surface dust was collected using modified hand vacuums, sifted and the fine particles analyzed for fungi, bacteria, endotoxin and cat and dust mite allergens.
Reasonable correlation between CO2 levels and passenger loads was observed for travel segments with variable passenger loads, such as trains and subways, which is consistent with fixed volume ventilation. CO2 levels were stable for the cruise portion of flight segments, but were significantly higher during preflight and post-flight periods, suggesting lower ventilation at times of increased passenger activity.
No significant differences in total fungal concentrations were noted between any transportation modes measured in 1997 or between concentrations in transportation environments and those from living room samples collected during early spring in Boston. Cat allergen was detected in most dust samples with the highest dust mite concentrations recovered from a train. Particle concentrations were highest in subways and generally higher on all ground transportation environments than on aircraft. VOC s associated with mobile sources were higher for ground transportation than for aircraft as were many other VOCs. Exceptions were acetone and ethyl alcohol, which were higher on aircraft.
Analysis of Two Jet Engine Lubricating Oils and a Hydraulic Fluid: Their Pyrolytic Breakdown Products and Their Implication on Aircraft Air Quality
Authors: van Netten C 
Published: April 2008

Aircraft air quality incidents are often traced to jet engine oil and/or hydraulic fluid leaking into bleed air used to ventilate the cabin. These contaminants can be subjected to temperatures in excess of 500°C. Exposed flight crew members have reported symptoms including dizziness, nausea, disorientation, blurred vision, and tingling in legs and arms.
Pyrolysis experiments of two jet engine oils and one hydraulic fluid at 525°C showed the engine oils to be important sources of carbon monoxide (CO). The same 5 out of the 10 possible tri-cresyl phosphate (TCP) isomers that were found in the bulk oils were found in the atmosphere at ambient temperatures after pyrolysis and were likely associated with smoke particles, illustrating an important potential route of exposure. Tri-orthocresyl phosphate (TOCP) was not found in the oils or fluid tested. The neurotoxin trimethyl propane phosphate (TMPP) was not found.
It was suggested that different symptoms could be expected depending on which fluid was pyrolized.
Proposed ASHRAE Cabin Air Quality Standard (161P)
Authors: Holcomb LC 
Published: April 2008

This preliminary material with regard to draft standard for Air Quality on Commercial Aircraft is presented here in hopes that it will aid in defining research needs for the future.
Aircraft are different from buildings. Commercial aircraft fly through an environment that is hostile to human life. Thus, safety features are of greatest importance. In a real-world setting, there will be trade-offs in comfort, safety and health.
The purpose of this standard is to define requirements for air quality in air carrier aircraft and specify methods for measurement and testing in order to establish compliance with the standard.
The scope of the standard covers: • Commercial aircraft carrying 19 or more passengers • Considers chemical, physical and biological contaminants as well as, but not limited to moisture, temperature and pressure • Will not ensure acceptable aircraft cabin air quality for everyone.
The committee has developed a draft standard and an informative appendix. Information on ventilation rates, contaminant standards, relative humidity, temperature, pressure and filtration will be presented.
Probabilistic Aspects of Life Prediction
Authors: Johnson WS , Hillberry BM 
Published: April 2008

Description
Seventeen peer-reviewed papers give you the latest information on probabilistic fatigue life prediction methodology, including how to accurately determine the useful life or inspection intervals for complex structures
Sections cover:
Probabilistic Modeling—life prediction, computational simulations, and service loading spectra
Material Variability—quality, performance, reliability, and uncertainties of various materials, including aluminum, ceramics, and steel, as they relate to fracture toughness and fatigue crack growth
Applications—realistic approaches to and applications of probabilistic fatigue life predictions
STP 1450 is a valuable resource for structural designers, fatigue and fracture engineers, and materials engineers who need to
RAH-66 Comanche Building Block Structural Qualification Program
Authors: Dobyns A , Barr B , Adelmann J 
Published: April 2008

The paper discusses the RAH-66 Comanche airframe building block structural qualification program. The components of the building block program included: material selection and qualification tests (lamina properties); coupon level tests (static and fatigue laminate properties, including open hole and filled hole strength, bearing, and sandwich compression after impact strength), and element, subcomponent, and full-scale tests. Element tests included bolted and bonded joint strength tests, beaded shear panel tests, sandwich shear panel tests, crippling tests and bearing-bypass bolted joint tests. Subcomponent testing included fuselage section crush tests, hydraulic ram testing of fuel tanks, and numerous design specific joint tests. The building block program culminated in the full-scale static test of the airframe structure.
The interaction of the building block program testing with the Comanche detail design is described including specific examples where results from compression after impact, tub crush, and hydraulic ram testing caused changes in the structural configuration of the aircraft. This paper discusses only the Sikorsky Aircraft portion of the RAH-66 building block program. Boeing-Philadelphia also performed a related program to substantiate the design of their portion of the aircraft.
Influence of Ply Waviness on Fatigue Life of Tapered Composite Flexbeam Laminates
Authors: Murri GB 
Published: April 2008

Nonlinear tapered flexbeam laminates, with significant ply waviness, were cut from a full-size composite rotor hub flexbeam. The specimens were tested under combined axial tension and cyclic bending loads. All of the specimens had wavy plies through the center and near the surfaces (termed marcelled areas), although for some of the specimens the surface marcels were very obvious, and for others they were much smaller. The specimens failed by first developing cracks through the marcels at the surfaces, and then delaminations grew from those cracks, in both directions. Delamination failure occurred in these specimens at significantly shorter fatigue lives than similar specimens without waviness, tested in Ref 2.
A 2-D finite-element model was developed which closely approximated the flexbeam geometry, boundary conditions, and loading. In addition, the FE model duplicated the waviness observed in one of the test specimens. The model was analyzed using a geometrically nonlinear FE code. Modifications were made to the original model to reduce the amplitude of the marcels near the surfaces. The analysis was repeated for each modification. Comparisons of the interlaminar normal stresses, σn, in the various models showed that under combined axial-tension and cyclicbending loading, for marcels of the same aspect ratio, σn, stresses increased as the distance along the taper, from thick to thin end, increased. for marcels of the same aspect ratio and at the same X-location along the taper, σn, stresses decreased as the distance from the surface into the flexbeam interior increased. A technique was presented for determining the smallest acceptable marcel aspect ratio at various locations in the flexbeam.
Open Hole Compression Strength and Failure Characterization in Carbon/Epoxy Tape Laminates
Authors: Bau H , Hoyt DM , Rousseau CQ 
Published: April 2008

Open hole compression (OHC) design criteria often size the thicknesses of composite aircraft skin structures. Therefore, there can be a significant payoff in improving OHC allowables through better characterization of OHC strength and behavior. This study, using progressive damage analysis and empirical methods, provides new insight into OHC strength and failure behavior.
OHC failure behavior was modeled using PDHOLEC, a progressive damage, 2-D finite-element code. Ultimate strength predictions were combined into carpet plots over a wide range of layups in three graphite composite material systems. A detailed evaluation of PDHOLEC progressive failure output resulted in the identification of several distinct predicted failure mechanisms. Predicted failure mechanisms and ultimate strengths are compared with OHC test data.
Two distinct failure mechanisms for OHC configurations were identified based on the PDHOLEC ailure study and strength trend studies of test data: a 0° ply kinking/buckling failure mechanism and a matrix cracking mechanism. The PDHOLEC predictions and test data were grouped by the identified failure mechanisms. Then curve fit equations were generated to characterize the ultimate strength behavior for each failure mechanism.
Finite Element Analysis of Delamination Growth in a Multidirectional Composite ENF Specimen
Authors: König M , Krüger R , Rinderknecht S 
Published: April 2008

Two different finite element models have been applied to the analysis of delamination growth in a multidirectional graphite/epoxy ENF specimen, which has previously been investigated experimentally. For a more accurate computation of energy release rates along the delamination front, and particularly the individual mode contributions, a layered 3-D shell finite element has been used. A 2-D finite element, based on Reissner-Mindlin plate theory, has been employed for simulation of the delamination growth. This element incorporates a process layer in which the delamination can grow. The virtual crack closure method is employed in both models to compute the energy release rates along the delamination front. It is postulated that these energy release rates control the development of the shape of the delamination front, as well as the final unstable growth of the delamination, as observed in the experiment.
By a comparison between simulation and experiment it is found that in the present case of pure shear mode (combination of Modes II and III) the Griffith criterion predicts correctly the global delamination growth.
Pendulum Impact Machines: Procedures and Specimens
Authors: Siewert T , McCowan C , Manahan M 
Published: April 2008

Description
Ten peer-reviewed papers cover the latest information on pendulum impact machines. STP 1476 represents the work of impact test researchers from around the world and provides input for further improvements in test methods, especially those used in construction codes and standards.
These papers are organized into four major areas:
Historical Developments in Impact Testing—covers the history and procedure development for Impact Testing
Impact Test Procedures and Machine Effects—discusses the effects on absorbed energy of removing and replacing an 8 mm Charpy striker
Reference Specimens—address certification of Charpy reference specimens at IRMM, uncertainty analyses on reference values of Charpy Impact Test Specimens, analysis of Charpy Impact verification data, and much more.
Issues with Instrumented Strikers—provides different approaches for the verification of force values measured with instrumented Charpy strikers
Evaluation of Laboratory Determined and Nondestructive Test Based Resilient Modulus Values from WesTrack Experiment
Authors: Seeds S , Alavi S , Ott W , Mikhail M , Mactutis J 
Published: April 2008

Resilient modulus is an important material property required for characterization of pavement layers for use in modern mechanistic pavement design. The resilient modulus can be determined in the laboratory using various types of tests, which measure a material's response under simulated field loading conditions. It can also be estimated from nondestructively measured pavement surface deflections and the so-called backcalculation procedures. Unfortunately, studies have shown that the resilient modulus determined from laboratory testing can differ significantly from that determined from nondestructive test (NDT) based backcalculation procedures.
This paper further addresses the issue by presenting the results of a site-specific comparison of the resilient modulus determined through laboratory testing and NDT-based backcalculation analysis. Unlike some of the earlier studies that focused more on developing a correlation between the two, this study explores some of the flaws and weaknesses of the two processes that are likely to result in the observed differences. It is also important to point out that the results of this study are based on an intensive amount of both laboratory and NDT data gathered from a pavement constructed to exceptional standards of construction quality, i.e., the WesTrack full-scale accelerated load test facility in northern Nevada.
The emphasis of the paper is on the unbound layers (i.e., base and recompacted subgrade soil layers) below the pavement surface. Although laboratory testing of the hot-mix asphalt (HMA) surface layer was completed, the data were not yet to a level of quality acceptance to produce a meaningful comparison with the NDT-based backcalculation results of the surface layer.
Use of Instrumented Dynamic Cone Penetrometer in Pavement Characterization
Authors: Nazarian S , Tandon V , Crain K , Yuan D 
Published: April 2008

The dynamic cone penetrometer data had been conventionally used for estimating the base and subgrade California bearing ratio. In recent years, a need for developing mechanistic pavement design procedures has been emphasized. However to develop mechanistic pavement design procedures, measuring engineering properties of pavement layers is essential. Two modifications to the existing dynamic cone penetrometer have been proposed in this paper for obtaining engineering properties of pavement layers.
First, an ordinary dynamic cone penetrometer was instrumented with a load cell and an accelerometer to determine the energy imparted to the ground, the resistance to the penetration, and the penetration of the device into the base and subgrade. A second device consisting of a three-dimensional accelerometer embedded in a DCP-like rod was developed to measure modulus and Poisson's ratio of the base and subgrade layers. This device can be placed in the same hole drilled for the first device, thus, requiring minimum coring. Although both devices are proven to be feasible, further analysis is needed for reliably extracting information from these measurements.