bluuebunny/crossref_metadata_2025 huggingface dataset:
Calorimetric Studies on Glasses and Glass Transition Phenomena
Authors: Chang S-S
Published: March 2009

Any material possessing a wide relaxation time spectrum which is a strong function of temperature will exhibit a glass transition as the mean relaxation time crosses the time scale of observation; for example, the metastable supercooled liquid freezes into a glass state. After a review of calorimetric investigation and characterization of the glassy state, the fictive temperature concept is recommended for the assignment of glass transition temperature. The glass transition temperature (Tg) is defined as the intersecting temperature of extensive thermodynamic properties (such as enthalpy, entropy, and volume) extrapolated from temperatures above and below Tg toward the Tg. This assignment of Tg is dependent only on the conditions of glass formation and is independent of the rate of observation. Therefore, the Tg so defined may be considered as a property of the glass, free of observational artifacts. The width of the glass transition is often 30 to 50 K; therefore, a description of the width and the intensity of the transition would be helpful. By slow cooling or annealing, not only a relaxation peak shows up, but the transition also appears sharper as the width narrows to about 10 K. A continuous slow cooling procedure is preferred over the annealing procedure to locate weak glass transitions, as annealing may produce more than one relaxation peak for exceptionally wide glass transitions. For glass transitions even harder to locate, Tg may be bracketed by using the relaxation nature of the glass, by observing spontaneous exothermic adiabatic temperature drifts of quenched glasses and endothermic drifts of slow-cooled or annealed glasses.
Analysis of DSC Thermal Curves for Assigning a Characteristic Glass Transition Temperature, Dependent on Either the Type or Thermal History of the Polymer
Authors: Saffell JR
Published: March 2009

DSC was used to study the thermal curve characteristics of four classical polymer glasses: polycarbonate (PC), anionic polystyrene (aPS), polysulfone, and polymethyl methacrylate (PMMA). The onset, peak, and fictive temperatures as well as endotherm characteristics were studied over two decades of heating and cooling rates. Assuming that the fictive temperature is independent of heating rate, the usefulness of Tonsetand ambiguity of Tpeak are demonstrated. The useful [heat/cool] ratio allows use of Tonset to calculate the effective cooling rate of the sample (which is easier to calculate thanTfictive). Comparison with results from annealed samples are shown. The fictive and onset temperatures can be used together to improve the reliability of glass temperature characterization and results are surprisingly constant between the four different types of glasses, leading to a method of providing a single temperature to characterize the thermal history/morphology using a DSC thermal curve. The peak temperature is nearly independent of thermal history, and so provides a characterization parameter that is insensitive to manufacturing and molding procedures.
Assigning the Glass Transition Temperature in Oriented Poly(ethylene terephthalate)
Authors: Moscato MJ , Seyler RJ
Published: March 2009

Thermoplastics like poly(ethylene terephthalate) (PET) can be melt processed into sheet and film formats for a variety of applications. Fabrication of these formats often involves application of a drawing process which can include drafting, tentering, heat setting, detentering, and heat relaxation. These various components add a thermomechanical history to the PET that will influence the glass transition. Thermomechanical analysis (TMA) in both the compressive mode and the tensile mode along with differential scanning calorimetry (DSC) techniques have been applied to a series of seven PET films generated using different drawing processes applied with an Iwamoto Biaxial Stretcher on extruded sheet from a single source. These measurements were undertaken to assign a glass transition temperature for each film. The assigned temperature ranged between 70°C and 94°C. Orientation and heat setting increased the temperature assigned as Tg while detentering both increased and lowered Tg on a direction-specific basis. Both the measurement technique and the assignment protocol employed to determine Tg contributed to differences in the assigned value. DSC results suggested the presence of two amorphous domains (mobile and constrained) in the film oriented uniaxially without constraint. TMA data demonstrated the assigned Tg may be direction specific and not a bulk property in oriented PET films.
Biomechanical Measurements: Pedestrian Coefficient of Friction
Authors: Gray BE , Jablonsky RD , Yoshida H
Published: March 2009

A physical measurement procedure is described for high production data generation and evaluation of the biomechanical coefficient of friction required for a large spectrum of pedestrians involving multiple footwear, substrate, and gait velocities. The testing technique and method of analysis of the collected data can be utilized in evaluation of the biomechanical coefficient of friction for the multiple degrees of freedom of the pedestrian gait model. It is hoped that such a test method will help standardize the collection of force plate data as they relate to shoe-floor interaction. For the range of gait velocities tested the data collected appear to lend support to the hypothesis that a factor of safety exists for the static coefficient of friction (COF) which is set forth in ASTM Designation D 2047 as providing nonhazardous walkway surfaces.
Innovative Technology in Sludge Processing—Lime Stabilization/Pasteurization Versus Traditional Methods
Authors: Berman S
Published: March 2009

Present and promulgated Environmental Protection Agency (EPA) regulations require that sludges generated by waste water treatment plants be treated prior to their discharge into the environment. There are several ways to achieve the reduction in volatile solids or pathogen kill, or both, required by these regulations. Of all the methods available, the combination of lime stabilization and pasteurization, using the heat of hydration as the sole heat source for pasteurization, has distinct advantages and disadvantages. The applicability of this innovative technique shall be proven in this brief overview.
Comparative Study of Carbon Polymer Composite and Titanium Femoral Stems in Dogs Using Computed Tomography
Authors: Cheal EJ , Grierson AE , Reilly DT , Sledge CB , Spector M
Published: March 2009

Clinical evaluations of canal-filling, uncemented, femoral stems continue to reveal a loss of density and thickness of the cortex of the proximal femur, consistent with a stress-shielding process. This finding has stimulated interest in the implementation of more flexible carbon fiber-reinforced polymer (CFRP) composite devices. In this study, unilateral total hip arthroplasty was performed on 34 canines using CFRP or geometrically identical titanium alloy femoral endoprostheses for periods of 6, 12, or 24 months. The CFRP composite stems had approximately one-half the bending stiffness of the metallic controls. The collarless, straight stems had a canal-filling design developed expressly for dogs. The prostheses were uncoated, with a relatively smooth surface, and were implanted with a press-fit. Computed tomography (CT) was used to quantify the remodeling of bone around the implants. With calibration of the CT images, we were able to calculate material and structural properties of the bone around the implants and in the contralateral femora, including the bone cross-sectional area and apparent density. To date, 6 of the 34 animals suffered fracture of the proximal femur. In the present investigation, CT analyses were performed on the remaining animals that were sacrificed after 6 or 12 months (a total of 20 animals). The results of these analyses indicated marked new bone formation with an increase in the quantity of radiodense bone, especially in the femoral metaphysis, and around the distal end of the stem. However, the mean bone density decreased due to the lower density of the newly formed bone, with a trend of more normal bone density at 12 months in comparison to 6 months after surgery. The occurrence of fractures and the observed remodeling suggest that the stresses in the proximal femur were relatively high, most likely due to the smooth-surfaced, press-fit, canal-filling design of the endoprostheses. Twelve months after surgery, the bone remodeling around the CFRP prostheses was not significantly different than the remodeling around the titanium alloy devices. The remodeling response could best be described as a redistribution of bone that was probably not yet complete even after 12 months. Longer-term results might reveal differences in the homeostatic structure of bone around the metallic and more flexible composite stems.
A Mechanical and Histological Analysis of the Bonding of Bone to Hydroxylapatite/Polymer Composite Coatings
Authors: Zimmerman MC , Boone PS , Scalzo H , Parsons JR
Published: March 2009

Two experiments were conducted to evaluate hydroxylapatite/polymer composite coatings as bone attachment vehicles for polymers. In the first, bone attachment to two classes of hydroxylapatite (HA) coated polymers was evaluated mechanically and histologically. Particulate HA was molded into the surface of thermoplastic implants and cast into the surface of thermoset implants. Coated and uncoated specimens were implanted in the distal femurs of rabbits for four and twelve weeks. In a second experiment, a roughened surface polysulfone implant was created by imbedding particulate HA into a polysulfone (PS) rod. A second material was created where HA particles were imbedded in the PS rod and the surface of the composite was machined smooth. Smooth and coated implants in both experiments were implanted transcortically in the distal femurs of rabbits for four and twelve weeks.

After sacrifice, the bone/implant interface of all the implants was evaluated mechanically by means of a push-out test with a servohydraulic test system. Paired statistical analysis revealed significantly greater shear strengths for coated versus uncoated implants for both polymer systems (thermoplast and thermoset) at both time periods in the first experiment. The results of the second experiment showed a statistically significant increase in shear strength for the rough surfaced HA/PS implant when compared to the smooth surfaced HA/ PS implant at each time period. Histology at both time periods indicated direct bone apposition to the HA coating as compared to a fibrous encapsulation using the uncoated implants.
Requirements of an Ideal System for Operating Room and Intensive Care Alarms and Information Transfer
Authors: Hedley-Whyte J , Milamed DR
Published: March 2009

Operating rooms are complex workplaces with a high turnover of patients, information, personnel, pathology specimens, and, on occasion, blood. When the enormous revenue generated by modern operating rooms and ancillary services is considered, the means of information transfer currently available are inadequate for both optimal patient safety and clinical and fiscal efficiency. Specific problem areas in operating room information transfer relating to hospital transportation departments, fiscal services, blood banks, pathology and blood gas laboratories, preoperative patient evaluation, pharmacies, and virology are addressed to provide recommendations for system development. Recent progress in operating room and intensive care alarm and patient monitoring systems further emphasize the need for improved information transfer as a cornerstone of a hospital's quality assurance program. Our institution has developed prototype information systems which address many of these issues.
Sensory Segmentation: Comparison of Attitudinal and Behavioral Methods
Authors: Moskowitz HR
Published: March 2009

Individual differences in sensory preference can be reduced to a more fundamental set of “sensory preference segments.” These segments comprise individuals exhibiting similar preference profiles, either attitudinally (such as, similar stated sensory likes/dislikes) or behaviorally (such as, similar patterns relating overall liking to sensory intensity). Behavioral sensory segmentation based upon actual patterns relating liking to sensory intensity of attributes shows dramatic differences among the segments. Behavioral sensory segments are often polar opposites of each other. In contrast, segmentation based upon attitudes toward the sensory attributes of a product shows less divergent, more similar patterns. Behavioral sensory segmentation is thus the more powerful method by which to assess individual differences. It presents the possibility that there may exist “preference genotypes” in the population, and that the demographic variability often observed in consumer “taste tests” may result from different distributions of the same basic primary groups.
The Influence of Sauce, Spice, and Name on the Perceived Ethnic Origin of Selected Culture-Specific Foods
Authors: Bell R , Paniesin R
Published: March 2009

Foods have been described as being ethnic by anthropological, culinary and historical definitions, but no experimental definition describes what characteristics of these foods influence their being perceived as ethnic by consumers. By factorially removing the characterizing sauce, spice, and name from several ethnic foods, we determined the extent to which each of these variables influences consumers' perceptions of a food item as belonging to a particular ethnic cuisine. Basic chicken and sauce recipes from Chinese, Mexican, Italian, Cajun, Indian, and Black/Southern cuisines were studied. Results suggest that Chinese, Mexican, Italian, Indian, and Black/Southern food ethnicity can be influenced by sauce alone or by a sauce/name combination; Indian ethnicity also can be influenced by spice alone. A spice/name combination influenced perception of Cajun ethnicity, although respondents confused Cajun samples with Mexican, Italian, Indian, or Black/Southern, depending upon which variable was removed.
Dynamic Force Measurement Vehicle (DFMV) and Its Application to Measuring and Monitoring Road Roughness
Authors: Ashmore SC , Hodges HC
Published: March 2009

A method for measuring the longitudinal profile of a highway or off-highway surface is given. As a paper presented at a “Vehicle, Tire Pavement Interface” meeting, this profile method is of particular interest to those involved in the study of vehicle response, as well as pavement roughness. The advantages and uses of a wave-number spectrum presentation of road roughness is discussed.
Measurement and Modeling of Truck Tire Traction Characteristics
Authors: Kulakowski BT , Chi M-C , Lin C-M
Published: March 2009

A new truck tire tester was built to measure tire forces in braking and cornering under various speed, vertical load, and slip angle conditions, and on different pavement surfaces. Six of the most common truck and bus tires were tested. In general, rib tires performed better than lug tires and radial tires performed better than bias-ply tires. All of the independent test variables such as pavement type, vehicle speed, axle load, and slip angle, have a significant effect on tire traction. The experimental data were processed to derive 48 regression models relating peak and sliding coefficients of braking and cornering friction and critical longitudinal slip to the independent variables.
Past and Future Analysis of Moving Dynamic Loads on Structures
Authors: Sheffey CF
Published: March 2009

The following is a sketch of the history involving the problem that deals with the effects of moving loads on bridges. This discussion focuses on the stages by which the various dynamic effects were introduced, primarily with respect to railway bridges, where the effects were first recognized as significant. The early application of these same methods to highway bridges is traced, recognizing that the problem of determining a proper design allowance for dynamic effects in highway bridges has stochastic aspects. The application of modern matrix, finite element models and numerical integration on digital computers is noted. In the summary, more attention to the probabilistic aspects of the problem is requested.
Impact of Reformulated Gasoline on Emissions from Current and Future Vehicles
Authors: Colucci JM , Benson JD
Published: March 2009

Gasolines reformulated specifically for reducing vehicle emissions will result in the most significant changes in the U.S. refining industry since the advent of unleaded gasoline. This paper will review the results from the Auto/Oil Air Quality Improvement Research Program showing the beneficial effects on vehicle emissions of individually decreasing gasoline aromatic, olefin and sulfur contents, 90% distillation temperature, and Reid vapor pressure, and of adding oxygenates. The paper discusses the importance of reformulated gasolines for reducing emissions from existing vehicles by complying with requirements in the Clean Air Act and California's Low Emission Vehicle/Clean Fuels Program. It will show the importance of controlling specific aromatic and olefin compounds in gasoline, and it will discuss how automotive manufacturers will utilize reformulated gasolines to meet future stringent vehicle emission standards.
Evaluation of Isopropyl Alcohol as an Alternative Solvent for Chlorofluorocarbons in the Cleanliness Verification of Aerospace Hardware and Ground Support Equipment
Authors: Bassett CW , Welch PJ
Published: March 2009

Presently at Kennedy Space Center (KSC) 1, 1, 2 trichloro-2, 2, 1 trifluoroethane (Chlorofluorocarbon-113) is the solvent used for precision cleaning of aerospace hardware. Chlorofluorocarbon-113 (CFC-113) is used in the precision cleaning operation for the final rinse and as the test solvent for cleanliness verification, which consists of particulate and Nonvolatile Residue (NVR) analysis. Although the major CFC replacement effort at KSC is to develop aqueous cleaning and cleanliness verification methods, some applications will still require solvent use. Isopropyl Alcohol (IPA) has been selected as a potential replacement solvent. IPA is an approved test solvent in accordance with KSC's Specification for Surface Cleanliness of Fluid Systems (KSC-C-123F); however, in sampling some Nonvolatile Residue (NVR) materials, several of the test results indicate IPA is not as efficient as CFC-113. This paper presents some of the difficulties associated with the use of IPA as a replacement solvent in the Precision Cleaning and Cleanliness Verification processes at KSC.
Evaluation of the Differences in Performing Particle Analysis with Water Instead of CFC Fluids
Authors: Welch PJ
Published: March 2009

Most aerospace cleaning specifications require particulate analysis as part of the cleanliness verification process. Trichlorotrifluoroethane, CFC-113, is presently the test solvent of choice for cleanliness verification.

It has been proposed to use water to replace CFC-113 as the test solvent for cleanliness verification; however it has been speculated that the differences in the physical properties between the two fluids will result in significantly different results in the particle analysis.

A comparison of deionized water versus CFC-113 has been conducted for several types of sampling of components. This paper presents a description of the tests, the test results, observations, and conclusions regarding the subject.
Aqueous Nonvolatile Residue Validation of Precision Cleaned Hardware
Authors: Allen GJ , Hoppesch CW , Johnson RS , Buckley M
Published: March 2009

In response to the need for finding alternatives to chlorofluorocarbons as a solvent in the precision cleaning process, the effectiveness of water as a replacement solvent is being evaluated. Tests have been conducted using ultrasonics and the Rosemont DC-190 Total Organic Carbon Analyzer (TOCA) as a method for determining the nonvolatile residue analysis in water. Preliminary test data indicates that the TOCA correlates well with turbidity measurements in the detection of selected contaminants in an aqueous matrix. The process is currently under evaluation in the precision cleaning laboratory.
Evaluation of Long-Term Thermal Performance of Cellular Plastics Revisited
Authors: Bomberg MB , Kumaran MK
Published: March 2009

Since the Montreal Protocol has established restrictions on the use of substances, that deplete the ozone layer, evaluation of performance of foams manufactured with alternative blowing agents, partially halogenated hydrochlorofluorocarbons (HCFC) in particular, became a high priority issue.

This paper reviews the issues involved in the evaluation of long-term thermal performance under service conditions and presents an agenda for further research.
Forced Convection Effects in Fibrous Thermal Insulation
Authors: Silberstein A , Arquis E , McCaa DJ
Published: March 2009

We relate experiments carried out both in the lab, in a guarded hot box, and in experimental test houses. It is shown that forced convection does not significantly affect the thermal properties of the insulation under the air velocities usually found in the cavities, unless the construction mode and/or workmanship allow multiple air entry zones, or discontinuities in the insulation or in the internal air barrier.

A computer model was also developed to help us understand the convective flow patterns inside the porous insulation, as induced by the forced convection above it. A fairly good agreement with experimental results could be obtained.
Interlaboratory Comparison of the Apparent Thermal Conductivity of a Fibrous Batt and Four Loose-Fill Insulations
Authors: McCaa DJ , Smith DR , Desjarlais A , Graves RS , Mumaw J , Noonan P , Scott JA , Sikund R , Troyer R , Zarr R
Published: March 2009

An interlaboratory comparison of measurements of the apparent thermal conductivities of four loose-fill insulations was conducted according to ASTM Standard Practice C 687 in order to prepare a revised statement of precision and bias. The apparatus used included one guarded hot plate, one thin-heater apparatus, and eight heat-flow meters. All specimens were tested at a mean temperature of 24 °C (75 °F). Test results for fibrous glass blanket were used to characterize the basic imprecision (numerical measure of precision) of the test instruments. The 2σ imprecisions of measurement of apparent thermal conductivity were 2.8% for fibrous glass blanket, 5.8% for cellulose, 9.4% for unbonded glass fiber, 10.5% for mineral wool, and 5.0% for perlite.
Effects of Aeration on Corrosiveness of Wet Residential Building Thermal Insulation on Low Carbon Steel
Authors: Stansbury EE
Published: March 2009

The corrosion behavior of low carbon steel in wet residential building thermal insulation and filtered insulation leachates were investigated with variable access of air to the corroding interface. Aqueous environments were characterized in terms of solubility of leachable species, pH and specific resistivity. Several electrochemical methods were used to evaluate the general corrosion behavior and to estimate the corrosion rate. Direct corrosion rates were determined by weight-loss and comparisons made to rates in wet cotton using distilled water. Although the pH of the environments varied from 4 to 9.5, a major variable is access of oxygen to the metal interface. This was confirmed by studying the effect of depth of embedding and by partial embedding of steel specimens in wet insulation. Limiting oxygen concentrations in leachates were established by air and nitrogen sparging which changed the corrosion rate by factors greater than ten. An additional variable is the effect of composition of the leachate on the adherence and porosity of the corrosion product deposit. Electrochemical polarization measurements provided information on the corrosion mechanisms.
Dynamic Fracture Toughness of Modified SA508C12 in the Ductile-to-Brittle Transition Region
Authors: Miglin MT , Wade CS , Joyce JA , Van Der Sluys WA
Published: March 2009

Fracture toughness testing of steels in the ductile-to-brittle transition region is complicated by a high degree of data scatter. Variations in the amount of ductile tearing prior to cleavage initiation often accompany the data scatter. Dynamic toughness testing is shown to be experimentally successful at reducing the incidence of prior ductile tearing. For the displacement rates tested, dynamic toughness values are at or above the lower-bound static toughness. Analysis of transition region toughness data using Weibull statistics, available energy analysis, and a constraint correction procedure is discussed.
Determination of JIc for Polymers Using the Single Specimen Method
Authors: Chung WN , Williams JG
Published: March 2009

The fracture toughness of several polymes is characterized using the J-integral method. The single specimen method has been applied, and the tests were conducted on three-point bend specimens of polyvinylidine difluoride, medium and high density polyethylene. The results are compared with the J-R curves obtained from the multiple specimen method, which is often used for polymers and has proved to be successful. This has enabled a good degree of confidence be attached to the single specimen method. For each type of polymer, the J-R curves obtained from both methods are in good agreement. Hysteresis loops are observed during unloading and reloading because of the viscoelastic nature of the polymers, and the shape of the loops was affected by the friction at the support rollers. The distinction of JIc values determined according to the ASTM Standards E 813-81 and E 813-87 is shown. The E 813-87 procedure predicts a more consistent JIc value than the E 813-81, but the adoption of the 0.2 mm offset blunting line does not reflect the actual initiation point and the advantages and drawbacks of each method are discussed. The blunting line suggested in the E 813 protocols is found to be inappropriate for describing the blunting mechanisms of polymers. Some tests were performed at different loading rates to determine the rate sensitivity of both the JIc values and J-R curves. It is suggested that the maximum allowable crack extension recommended for the J controlled growth condition is too conservative for polymers, and it is noted that the crack growth is difficult to measure accurately. A maximum allowable crack extension of 10% of the uncracked ligament is considered to be appropriate.
A Method to Monitor Release of an Insecticide From Granules into Soil
Authors: Stein JA , Kallay WB , Goss GR , Papadopoulos LK
Published: March 2009

A method has been developed to monitor the release of an insecticide from granules into soil. Pesticide release from granules and subsequent movement into the soil is an important parameter in pesticide performance. To date, no quantitative measurements have been made. Past studies have concentrated on either bio-assays or content in the soil solution. Many field efficacy studies have been performed. The described method measures quantitatively release of an insecticide into the soil environment in the laboratory. This method consists of placing pesticide containing granules into a pulverized soil. This mixture is then incubated. Periodically the samples are removed, the clay granules separated from the soil and the soil analyzed for pesticide content. Using this technique the effects of temperature, time, soil moisture, carrier type, etc. are able to be monitored for their effects on pesticide release. The method and some of these effects are discussed.
Compressed Tablets as a Potential Pesticide Delivery System
Authors: Ibrahim NI , Mehra DK
Published: March 2009

Solid and liquid pesticides can be formulated into tablets as a delivery system. Inclusion of Lattice™ microcrystalline cellulose (MCC), a special grade of MCC for agricultural application, and Ac-Di-SolR croscarmellose, a cross-linked sodium carboxy methylcellulose (XL-CMC), into the formulation provides a rapid tablet disintegration time of not more than 5 minutes. Lattice MCC acts as an excellent dry binder when the pesticide is compressed thus imparting desired hardness to the tablets. Simultaneously, the XL-CMC being an excellent disintegrating agent, provides the desirable rapid tablet disintegration time. The tablets disintegrate to prime particles and do not form a hard pack when the suspension is left undisturbed for 1–3 days.
Pesticide Compatibility: The Effect of Carrier
Authors: Becher DZ
Published: March 2009

The routine use of pesticide tank mixtures has increased the importance of formulation tank mix compatibility. Unfortunately, compatibility is very sensitive to the mixing and spraying conditions. Consequently, incompatibility occurs erratically in the field and is difficult to consistently reproduce in the laboratory. While compatibility in the field can never be totally predicted in the laboratory, the test method used in this work provides good predictions, while still allowing the testing of many combinations of pesticides and carriers with a reasonable effort.

It is known that the results of compatibility tests are dependent on the spray carriers used. It was not known whether tests with laboratory carriers would adequately predict field results. Therefore, samples of water and ammonium nitrate/urea liquid fertilizers were obtained from various parts of the United States and their effect on the compatibility of pesticide tank mixtures evaluated. Samples of nominally similar carriers gave very different compatibility results. The importance of using carriers which are representative of the ones used in the field when evaluating pesticide tank mix compatibility was confirmed.
Solvent and Surfactant Influence on Flash Points of Pesticide Formulations
Authors: Catanach JS , Hampton SW
Published: March 2009

Intensified regulatory activity from various sources is guiding the consideration of higher flash (lower volatility) materials as preferred components in pesticide formulations. An update on the current issues surrounding storage and packaging of flammable and combustible liquids is presented.

For this paper, the term “components” refers to nonactive materials and includes solvent or solvent blends and surfactants used in the formulations. The purpose of this paper is to study the effect of multiple component solvent systems on flash point. Also, the effect of surfactants in the formulation will be reviewed.

Nonlinearity of flash points when different components are blended for the purpose of improving active solubility, formulation efficacy, evaporation rate, or other parameter is demonstrated.
Relationship Between Surfactant Characteristics and the Phytotoxicity of CGA-136872
Authors: Manthey FA , Horsley RD , Nalewaja JD
Published: March 2009

Research was conducted to determine the relationship between the phytotoxicity of CGA-136872 and the chemical and physical properties of surfactants. All surfactants tested greatly enhanced CGA-136872 phytotoxicity to quackgrass. Surfactant enhancement of CGA-136872 phytotoxicity increased, peaked, and decreased as surfactant hydrophilic:lipophilic balance (HLB) increased. The peak or optimum HLB ranged from 11.9 to 14.3. Surfactants that differed in chemistry but had an HLB in the optimum range differed in their enhancement of CGA-136872 phytotoxicity to quackgrass. Surfactant characteristics that promoted quackgrass control with CGA-136872 were low molecular weight, low surface tension, low cloud point temperature, low pour point temperature, and HLB between 11.9 and 14.3.
Comparison of Techniques in Gas Analysis
Authors: Risch SJ
Published: March 2009

Gas analysis is a method used to obtain a sample of volatile compounds present in the atmosphere or in the vapor phase above a sample in a sealed container. Headspace analysis is one specific method that is defined as the mixture of vapors which exists in equilibrium with a sample held in a closed system. Gas sampling consists of two different types of procedures. These are termed direct gas sampling and gas concentration. Direct gas sampling is an easy procedure, but it is much less sensitive than gas concentration. These techniques will be discussed and their advantages and disadvantages presented. Methods to increase the sensitivity of these techniques including splitless injections, cryofocusing, and temperature of equilibration will also be presented.
New Technologies for Use in Acid Deposition Networks
Authors: Drummond JW , Castledine C , Green J , Denno R , Mackay GI , Schiff HI
Published: March 2009

Several new developments associated with the sensitive Luminox NO2 monitor (the LMA-3) are presented: (1) A peroxyacetyl nitrate (PAN) converter has been developed for use with the LMA-3. It achieves a 3-sigma detection limit of 30 parts per trillion (ppt) with a time cycle of 5 min, which allows measurements in even clean background air. It is presently being commercialized with an integral Luminox detector. (2) A second converter/sequencer for NOx (NOx = NO2 + NO) and NO2 is described. It uses CrO3 for the NO conversion and presents significant advantages over the competitive commercial NOx detectors presently available, namely, sensitivity down to 10 ppt or less, and virtual freedom from interferences that now plague other methods. (3) An ozone scrubber has been developed that removes ozone (O3) from the sample air without destroying more than 10% of the NO2. This removes the major interference associated with the luminol method for NO2 measurements. Finally, the nonlinearities outside of the 1 to 50 ppb range have been characterized. An algorithm is presented for making corrections to ambient measurements, not only for nonlinearities but for residual ozone and PAN interferences. Typical atmospheric measurements (PAN, NO2, NOx, and O3) are given both for clean background air and for urban air in Long Beach, California.
Strategies for Continuous Monitoring of Hydrogen Chloride Emissions from Municipal Solid Waste Incinerators
Authors: Rollins R , Logan TJ , Midgett MR , Jernigan JR , Shanklin S
Published: March 2009

This paper presents a discussion of sampling and analytical techniques for continuous monitoring of hydrogen chloride (HCl) emissions from incineration sources. The discussion focuses on commercially available systems for sample conditioning and measurement. Six HCl continuous emission monitors were evaluated at a municipal facility for solid waste incineration. Field test results indicate that several techniques for continuous monitoring of HCl concentrations are available. Most of the analyzers tested, regardless of the detection or calibration techniques, indicated the same trend in the effluent HCl concentrations and produced data that were in good agreement with wet chemistry results.
Sampling and Analysis of Nitrogen Dioxide and Respirable Particles in the Indoor Environment
Authors: Treitman RD , Ryan PB , Harlos DP , Soczek ML , Yanagisawa Y , Spengler JD , Billick IH
Published: March 2009

In this work we describe sampling and analytical methodologies for nitrogen dioxide and respirable particles in indoor environments. Advantages and disadvantages of each technique are explored. To indicate the utility of certain of these techniques, results from large-scale surveys of exposure to nitrogen dioxide are presented. These surveys include (a) population-based home characterizations and personal monitoring designed to assess exposures, (b) investigations of nitrogen dioxide and respirable particle concentrations and associated health effects from an epidemiological point of view, and (c) the investigation of shortterm exposures to nitrogen dioxide during commuting and cooking events. Issues associated with field implementation of the samplers, such as quality control and ease of use, are discussed.
Airtightness Characteristics of Electrically Heated Houses in the Residential Standards Demonstration Program
Authors: Parker DS
Published: March 2009

This paper examines airtightness data from 623 electrically heated residential buildings in the Pacific Northwest. The Residential Standards Demonstration Program (RSDP) was designed to demonstrate the merits of energy-efficient construction techniques. The control houses were intended to be representative of current construction practice in the four-state region (Idaho, Montana, Oregon, and Washington). The Model Conservation Standards (MCS) houses incorporated energy efficiency features including measures to reduce air infiltration and provide ventilation with heat recovery. The RSDP houses were primarily built in 1984 and monitored in the 1985–1986 heating season.

The airtightness of the tested homes was found to highly variable. Based on interpretation of blower door tests with the LBL infiltration model, we conclude that the typical MCS home had an average natural air change rate of about 0.25 air changes per hour (ACH) versus a rate of 0.49 ACH for the typical control house.
Real-Time In-Situ Monitoring of Dredge Disposal Sites
Authors: Baldwin KC , Irish JD , Bokuniewicz HJ
Published: March 2009

The University of New Hampshire is utilizing “smart,” remote, telemetering instrumentation for the real-time monitoring of the ocean environment. These techniques are being adapted to the dredged sediment disposal site monitoring problem, in particular, short-term monitoring during the discharge of dredged sediment and the long-term monitoring of the disposal mound after capping.

The goal of short-term monitoring is to collect sediment distribution and water property data that facilitate (1) studying the physical processes at the site, (2) monitoring the discharge operation, and (3) designing an efficient cap. To achieve this, the disposal site must be continuously monitored, and the lateral spread of dredged sediment, the amount of sediment deposited at and advected off the site, and the gross mound geometry and growth must all be estimated. The time and position of the dredged sediment during the actual discharge operation are recorded and relayed back to shore in real time as an artifact of this monitoring. This information is available to local and federal authorities charged with policing the disposal site.

The goal of long-term monitoring is to assess the dredged sediment mound and cap performance to insure that any contaminated sediment is safely contained. Satisfactory performance of a disposal site is defined here as small vertical settlement, no geotechnical instability, or no storm induced erosion effects. The detection of these effects drives the need for particular sensor and instrument configuration. The time series data acquired with these systems will allow making first order decisions regarding possible mound (dredged sediment/cap) performance inadequacies. The inadequacies may result in possible sediment resuspension and transport, and water column contamination.

Using modern developments in microprocessor-controlled instrumentation, acoustics and packet radio telemetry, general purpose, remote instrumentation is easily deployed for one year to monitor the ocean environment and telemeter data to shore in near real time. Acoustic and optical techniques for monitoring suspended sediment, as well as the usual physical oceanographic sensors can be interfaced to the bottom mounted instrumentation for these monitoring operations.
A Seabed Sediment Sampler for Ocean Waste Disposal
Authors: Smits FP
Published: March 2009

The paper presents a review of some sampling techniques for soft ocean sediments. The review includes a few new developments, which have been the result of recent waste disposal research programs. Emphasis of the paper is put on the problem of sample disturbance. Various sources of disturbance are discussed. The principles of sampler design are examined on their ability to eliminate such causes of disturbance
A Case Study of Geotomography Applied to a Detailed Investigation of a Highway Bridge Foundation
Authors: Saito H , Shima H , Toshioka T , Kaino S , Ohtomo H
Published: March 2009

Three types of geotomographic surveys (seismic tomography, resistivity tomography, and radar tomography) were conducted at a highway bridge pier construction site to investigate rock characteristics. After the geophysical investigation, bedrock was excavated to construct the bridge foundation. Geological surveys and plate-loading tests were carried out on the excavated surface. The geophysical and geological results were generally in good agreement.

Seismic tomography can distinguish highly fractured rock from unfractured rock, and resistivity tomography and radar tomography can classify rock according to different water contents. The combined use of these three geotomographic surveys made it possible to detect the anomalous zone which was highly fractured and saturated.
Applications of the Thermal-Pulse Flowmeter in the Hydraulic Characterization of Fractured Rocks
Authors: Hess AE , Paillet FL
Published: March 2009

The U.S. Geological Survey has developed a thermal-pulse flowmeter capable of detecting borehole flows to as small as 0.04 L/min. This new flowmeter provides much greater sensitivity to slow vertical flow than that available using conventional spinner flowmeters. This paper describes five applications of the thermal-pulse flowmeter in the characterization of the hydrology of fractured rocks. These applications include measurement of flows in boreholes driven by ambient hydraulic-head differences, identification of fractures contributing flow during production tests, inference of fracture interconnections during aquifer tests, interpretation of water-quality contrasts in boreholes, and identification of fractures affected by hydraulic stimulation procedures. Each of the five applications is illustrated by specific examples selected from ongoing research activities at various fracture hydrology study sites.
Utility of Stereological Measurements in the Study of Creep Cavitation Kinetics
Authors: Gokhale AM
Published: March 2009

Applications of the stereological counting measurements are discussed for the study of intergranular cavitation process during high temperature creep. It is shown that the stereological data on volume fraction, surface area, integral mean curvature, and total line length can yield quantitative information on the various aspects of the kinetics of the cavitation process without involving any assumptions.
Monitoring More -- Measuring Less and Less
Authors: Cox GV
Published: March 2009

Scientists need to improve understanding of the significance of analytical results relative to the environment. Scientific methodology has progressed yielding an impressive ability to measure minuscule quantities of contaminants, but the ability to understand the significance of those levels in the environment has not kept pace. Scientists must also improve their ability to accurately measure materials in complex matrices. The third area requiring attention in this decade is sampling protocols. Too much contamination and improper sampling strategies are negating the accuracy of high-precision analytical efforts. These are the challenges of the 1990s.
Performance Testing of Selected Test Kits for Analysis of Water Samples
Authors: Spokes GN , Bradley J
Published: March 2009

Chemical testing kits represent a convenient, reliable, inexpensive and fast option for chemists testing various types of aqueous samples including drinking water, ground water, wastewater and industrial process streams.

The three basic types of test kits are described. Easy-to-use chemical test kits are one type of kit that has found favor among its users. There is, however, a paucity of factual information about the accuracy and precision of these chemical test kits.

Data for selected CHEMetrics'[1] easy-to-use test kits are presented. Results of tests of colorimetric, photometric and titrimetric methodologies are described, including comparison data with EPA methods. Tests of nitrite-nitrogen, lead and quaternary ammonium compounds show that accuracy and precision may in some cases be lower than that of the standard method. The advantages and disadvantages of easy-to-use test kits are examined and the importance of good quality control in manufacturing is stressed. The benefits of kit tests are believed to outweigh any technical disadvantage provided the responsible chemist assures that the kit's accuracy and precision are adequate for the intended purpose.
Direct Sample-to-Column Purging with Whole Column Cryotrapping (P/WCC) for the Determination of Volatile Organic Compounds in Water
Authors: Pankow JF , Rounds SA
Published: March 2009

Volatile organic compounds (VOCs) ranging from chloromethane to chlorinated benzenes can be determined simply and easily by the P/WCC method. In P/WCC, a sample is purged directly to a fused silica capillary column. During the purging, the column (e.g., 0.32 mm i.d. DB-624) is maintained under whole column cryotrapping conditions. A water trap which condenses water minimizes the transfer of water to the column. P/WCC provides for the quantitative transfer of even the most volatile analytes to the column. (In purge and trap, very volatile analytes can break through the trap and be lost.) The simplicity of P/WCC minimizes blank levels; WCC permits very high chromatographic efficiency. Applications involving detection by mass spectrometry (MS) and an electron capture detector (ECD) are discussed. When using an ECD in the analysis of a 5 mL sample volume, then for o-dichlorobenzene, 1,2,4-trichlorobenzene, and 1,2,4,5-tetrachlorobenzene, P/WCC will give detection limits of 0.01, 0.003, and 0.0006 ng/mL, respectively.
Data Standardization--The Key to Effective Management
Authors: Wagner CR
Published: March 2009

Effective management of the nation's water resources is dependent upon accurate and consistent hydrologic information. Before the emergence of environmental concerns in the 1960's, most hydrologic information was collected by the U.S. Geological Survey and other Federal agencies that used fairly consistent methods and equipment. In the past quarter century, however, increased environmental awareness has resulted in an expansion of hydrologic data collection not only by Federal agencies, but also by state and municipal governments, university investigators, and private consulting firms. The acceptance and use of standard methods of collecting and processing hydrologic data would contribute to cost savings and to greater credibility of flow information vital to responsible assessment and management of the nation's water resources.

This paper traces the evolution of the requirements and uses of open-channel flow information in the U.S., and the sequence of efforts to standardize the methods used to obtain this information in the future. The variable nature of naturally flowing rivers results in continually changing hydraulic properties of their channels. Those persons responsible for measurement of water flowing in open channels (streamflow) must use a large amount of judgement in the selection of appropriate equipment and techniques to obtain accurate flow information. Standardization of the methods used in the measurement of streamflow is essential to assure consistency of data, but must also allow considerable latitude for individual judgement to meet constantly changing field conditions.