bluuebunny/crossref_metadata_2025_split huggingface dataset:
Used Tires as a Substitute for Drainfield Aggregate
Authors: Burnell BN , McOmber G 
Published: March 2009

This study summarizes the state of Idaho's approach to determine the suitability of reusing used tires for drainfield aggregate (drainrock) in standard subsurface sewage disposal systems and as a substitute for gravelless domed chamber systems. The used tire industry has developed alternative uses for used tires such as: a fuel supplement in incinerators, playground equipment, road building materials, marina boat dock bumpers, and for alternative daily cover at municipal solid waste landfills. Used tires are prohibited in Idaho from being disposed of in municipal solid waste landfills. The need exists to find several methods to reuse used tires because of the prohibition of landfilling tires and as an alternative to other more expensive methods of used tire disposal.
Researchers report that shredded tires do not release any significant amounts of priority pollutants. These reports provide a general indication that the use of used tires as road bed materials does not pose a risk to ground water. The use of chipped tires and half tires in drainfields has not been evaluated as to the potential for ground water contamination. This study addresses the information gap for use of waste tires in subsurface sewage disposal applications. Used tire chips as a substitute for drainrock release sulfer and zinc from the rubber, and iron from the reinforcing wire. This release of metals was not observed for the half tires placed in the gravelless domed chamber design.
Development of Emulsifiable Concentrate Formulations Using Experimental Design Software
Authors: Butler BJ 
Published: March 2009

This paper examines two experimentation processes for developing an emulsifier system for an EC herbicide formulation. The first process is the traditional method of single factor experimentation, and the second process uses DOE (Design of Experiments) computer software. A four component emulsifier system is optimized using both processes. The advantages and disadvantages of both processes are discussed.
The use of DOE techniques for mixtures gives the researcher a greater level of understanding of the interactions of the variables in the experimental system, compared to single factor experimentation. The software used in this study did create predictive models for the formulation developed, thus allowing the selection of the optimum blend of the components after evaluation of seventeen blends. The property selected for evaluation was emulsion separation as a function of water hardness.
Water in Oil Microemulsion Aerosol Systems for Insecticidal Compositions
Authors: Narayanan KS , Kaminsky M , Jon D , Ianniello RM 
Published: March 2009

Conventional aerosol as a delivery system for hydrophobic insecticides, formulated with hydrocarbon or freon type propellants [(A46) or Freon 11/12] are derived from matrices based on non-aqueous organic solvents, i.e., either hydrocarbons or halogenated hydrocarbons. Such systems pose potential environmental hazards like high flammability (hydrocarbon emission) and depletion of the ozone layer from fluorinated hydrocarbons, and emission of chlorinated hydrocarbons as cancer suspect agents. Totally aqueous systems are not easy to formulate in a single phase system as are aerosols. While O/W microemulsions are described in the literature, their use as trigger spray or aerosol systems produced low knockdown rates (speed of ‘kill’). A W/O microemulsion which will accommodate high levels (⩾ 35%) of conventional hydrocarbon propellant (A46) would be safer and will improve the knockdown rate.
This paper describes our effort in successfully formulating such W/O microemulsion systems. A systematic approach to stabilize W/O microemulsions that can accommodate high level of water (25–40%) as well as high level of hydrocarbon oil and hydrocarbon propellant (40–50%) based on partial phase diagrams produced several prototype formulations. These formulations matrices essentially consist of: nonylphenol ethoxylates as primary emulsifiers and long chain (C8) alkyl pyrrolidone/pentanol/ glycerol as cosurfactant/cosolvents, C12 hydrocarbon and water. Mixed pyrethroids and propellants can be loaded at appropriate levels.
Examples of prototype formulations, stability data, and biological efficacy are provided. A working model that would explain the high biological performance is also provided.
Liquid Formulations of Non-Spore Forming Microorganisms
Authors: Wacek TJ 
Published: March 2009

Biological formulations have evolved from the use of organic based solids such as peat as a preservative and delivery system to water based carriers. Water based formulations provide more convenience for the end user. Innovations in media preparation, stabilizing agents and packaging have led to stable formulations of non-spore forming microorganisms.
Liquid media for biological formulations contain either minimal nutrient levels packaged in air impermeable containers, or very high nutrient levels packaged in oxygen permeable plastic. Soluble polysaccharides (particularly alginates) can be used as stabilizing agents. Also, concentrated pastes of cells which are kept frozen until use, lyophilized powders, and oil suspensions are available. Two important points for the successful liquid formulation of a biological are long term stability (1 to 2 years) and effectivity at the site of use.
Why Organosilicone Adjuvants Spread
Authors: Hill RM , Burow RF 
Published: March 2009

The use of certain organosilicone surfactants as agricultural adjuvants has come about as a result of their unusual ability to promote the rapid spreading of dilute solutions on hydrophobic leaf surfaces. The reason for this unique spreading is not well understood.
The spreading of surfactant solutions, including the organosilicone surfactants, has recently been shown to exhibit a maximum in spreading rate as the surfactant concentration is increased, and as the substrate is made more hydrophobic. Certain organic surfactants promote spreading equally as rapid as the organosilicones on slightly less hydrophobic surfaces. Organosilicone surfactants, on the other hand, exhibit rapid spreading even on very hydrophobic surfaces. Some have attributed the rapid spreading of the organosilicone surfactants to their unique molecular shape, but the evidence does not support this. A correlation has been found between solubility or turbidity and spreading-those materials which form turbid dispersions seem to provide the most rapid spreading. In this case turbidity is due to the presence of a dispersion of bilayer vesicles. The presence of vesicles contributes to the low dynamic surface and interfacial tensions at short time scales, leading to the ability to spread more rapidly over more hydrophobic substrates.
Solid Adjuvant Systems — Formulations, Stability, and Efficacy
Authors: Narayanan KS , Talion M 
Published: March 2009

Adjuvants are increasingly used as a means of reducing pesticides in the environment by providing biological enhancement. Incorporation of adjuvants with the active ingredients can produce added value and product differentiation. Examples of solid forms of adjuvants that can provide multiple benefits are not very common. Solid adjuvants have several advantages like elimination of containers (using water dispersible/soluble bags), capability of direct incorporation with solid formulations (wettable powders, water soluble/dispersible granules), and use as tank mix additives.
Formulated value added multibenefit adjuvant systems (Agrimax 3 ™) are described in the literature [Narayanan, 1993]. These are optimized microemulsions containing alkyl pyrrolidones, anionic surfactants and water insoluble copolymers derived from vinyl pyrrolidones. Agrimax systems are designed to provide increased spreading, penetration and rainfastness. A second type of adjuvants is copolymers of vinyl pyrrolidones containing positive pendant groups (Restrict ™). Restrict ™ polymers are shown to reduce leaching of pesticides from the soil [Narayanan, et. al., 1993 a].
The above adjuvant systems were converted to value added solid forms by the use of specific complexing agents like urea. Prototype compositionsderived from the above adjuvant systems, preparative methods, stability, physical properties, and biological performance are discussed. The role of urea as a complexing agent is also discussed.
A Sweating and Moving Arm for the Measurement of Thermal Insulation and Water Vapour Resistance of Clothing
Authors: Weder MS , Zimmerli T , Rossi RM 
Published: March 2009

There are many methods of measurement to analyse the specifications of fabrics like heat transfer and water vapour permeability. However, in practice, the air layers between the different fabrics fundamentally influence the wear comfort. With the sweating arm developed at EMPA, it is now possible to simulate the heat and moisture transfer under realistic conditions. The goal of this study is to analyse the interactions between the different parameters which influence the thermal and water vapour resistance. These parameters are basically the temperature, the degree of humidity, different widths of the sleeves, the pumping effect of the movable forearm and the wind velocity.
The study shows that the thermal insulation of the air layers is 5 to 50 times higher than the material itself. Wide sleeves have in average a 30% higher thermal insulation than narrow sleeves.
It could be prooved that thermal and moisture transfer do not correlate with each other: for one sample, even if the wide sleeve has a much higher thermal insulation than the narrow one, the water vapour resistance is much lower.
Mixed Waste Solidification Testing on Polymer and Cement-Based Waste forms in Support of Hanford's WRAP 2A Facility
Authors: Burbank DA , Weingardt KM 
Published: March 2009

A testing program has been conducted by the Westinghouse Hanford Company to confirm the baseline waste form selection for use in Waste Receiving and Processing (WRAP) Module 2A. WRAP Module 2A will provide treatment required to properly dispose of containerized contact-handled, mixed low-level waste at the U.S. Department of Energy Hanford Site in south-central Washington State. Solidification/stabilization has been chosen as the appropriate treatment for this waste. This work will test cement-based, thermosetting polymer, and thermoplastic polymer solidification media to substantiate the technology approach for WRAP Module 2A.
Screening tests were performed using the major chemical constituent of each waste type to measure the gross compatibility with the immobilization media and to determine formulations for more detailed testing. Surrogate materials representing each of the eight waste types were prepared in the laboratory. These surrogates were then solidified with the selected immobilization media and subjected to a battery of standard performance tests. Detailed discussion of the laboratory work and results are contained in this paper.
Effects of Various Additives on the Solidification of Oily Sludges: A Bench-Scale Study
Authors: Kelly DS , Diethelm EC 
Published: March 2009

In preparation for closure of a RCRA hazardous waste site in Northern California, the oily impounded sludges will be solidified in situ using a cementitious system in order to support the closure cover. To determine mix ratios of additives to be used to solidify the sludges in the impoundments, treatability testing was completed. The testing consisted of first mixing the sludge with additives in small batches to determine the effect of various types and combinations of additives on the unconfined compressive strength (by pocket penetrometer testing) of the solidified material. Information learned in this testing was used to determine mix ratios to be tested in larger batches to evaluates caling changes and test for unconfined compressive strength by a more reliable method. The appropriate mix ratio determined in the second set of tests will be used as a guide to solidify the impounded sludge in situ.
Data from the impoundment tested indicates the largest observed effect on the final strength of the solidified material was due to varying the amount of fly ash added. Varying the amount of cement had a lesser observed effect on the final strength of the material. The data also indicates an increase in the strength of solidified material with the addition of relatively small amounts of bentonite in addition to other additives. Further increases in the amount of bentonite did not appear to affect the final strength.
Literature Review of the Interaction of Select Inorganic Species on the Set and Properties of Cement and Methods of Abatement Through Waste Pretreatment
Authors: Mattus CH , Mattus AJ 
Published: March 2009

It is a well-known fact that many inorganic species that may be present as a component of a complex aqueous waste can have an adverse effect upon the set of cements and subsequent properties of a final waste form product. Chemical species such as sulfates, aluminates, borates, phosphates, and zinc, to namea few, especially when present in combination, can result in false sets, flash sets, and expansive mineral phases along with many other unwanted changes in physical properties.
Generally, the approach is to adjust the type of additives present in a waste form formulation to compensate or sometimes to rely upon raw waste dilution to minimize or mitigate potential problems. Another approach which is discussed in this paper, in addition to a comprehensive literature review, is based upon an understanding of the chemistry of the waste solution and its components: that is, we rely upon pretreatment of the waste solution to prevent interactions during or after solidification. Various types of precipitation options are available for the removal of certain waste species, or we may simply alter them to a stable, more insoluble form. Undesirable reactions in the cementitious solid phase, as well as some of the various waste pretreatment options which are available, are discussed.
Correlation of Adjuvant Physico-Chemical Properties and Glyphosate Efficacy
Authors: Sun J , Singh M 
Published: March 2009

Greenhouse experiments were conducted to investigate the effect of adjuvants on glyphosate efficacy. Adjuvants evaluated were Silwet L-77, Kinetic, Dyne-Amic, Impact, Induce, Optima, LI-700, Freeway, X-77, and Agri-Dex. Tested two weed species were redroot pigweed (Amaranthus retroflexus L.) and barnyardgrass [Echinochloa crus-galli (L.) Beauv.]. In most cases, glyphosate, at 0.56 kg/ha, combined with adjuvants resulted equal or better control in both weed species. Optima was most effective for enhancing glyphosate efficacy. However, the combination of glyphosate with either Induce or Freeway showed antagonism.
Correlation of adjuvant physico-chemical properties and glyphosate efficacy was also analyzed. The results showed that contact angle and spreading coefficient had significant effect on glyphosate efficacy 1 week after treatment (WAT). As the time interval increased to 2, 3, and 4 WAT, the significance of the correlation decreased.
Instrumentation for Monitoring Buried Pipe Behavior During Backfilling
Authors: McGrath TJ , Selig ET , Webb MC 
Published: March 2009

An extensive instrumentation plan was devised to monitor buried pipe behavior, soil behavior and pipe-soil interaction during backfilling. The emphasis of the instrumentation plan was to monitor these parameters under different installation techniques without impeding construction operations.
Different types and sizes of pipe were selected for installation in trenches excavated in undisturbed in situ soil conditions. Installation variables included in situ soil conditions, trench widths, backfill material (including controlled low strength material), haunching effort, and compaction methods. A total of fourteen tests, each including reinforced concrete, corrugated steel, and corrugated HDPE, were conducted. Eleven of the installations were conducted with 900 mm inside diameter pipe and three with 1500 mm inside diameter pipe. The pipes were buried to a cover depth of 1.2 m.
Measurements of pipe shape, pipe strains, pipe-soil interface pressures, soil density, soil stresses, and soil strains were collected. Pipe shape changes were measured by a custom built profilometer. Custom designed bending beam pressure transducers were used in the steel pipe to measure interface pressures.
Most of the instrumentation performed well and measured results were within the range expected. Pipe-soil interaction effects were effectively measured with the instruments selected. Pipe shape changes were a very valuable parameter for investigating pipe-soil interaction.
A Comparison of Portable and Permanent Landfill Liner Leak Detection Systems
Authors: Taylor SB , White CC , Barker RD 
Published: March 2009

Monitoring of the integrity of electrically non-conductive geomembrane liners installed at waste sites using electrical geophysical techniques has been carried out for a number of years using above-liner leak location surveys and, more recently, below-liner monitoring systems. We compare the theoretical response of both types of survey to a hole in a liner and then compare with measurements made in the field. The theoretical leak response indicates that above-liner surveys are sensitive to leaks over a greater area, though both responses result in comparable leak detectability. However, field data suggest that in practice, measurements made on a sparse grid below the liner have the greater sensitivity to certain leaks. This may be due to the differing leak geometries and background conditions present above and below the liner.
The results indicate that a sparse below-liner monitoring grid, with its long-term monitoring capabilities, combined with above-liner surveys to pinpoint leaks accurately offer a successful approach to ensuring liner integrity throughout the lifetime of a lined waste site.
Attapulgite as a Suspension Control Agent and Rheology Modifier in Flowables
Authors: Ginez A 
Published: March 2009

Attapulgite, a naturally occurring mineral known also as palygorskite, is a 2:1 clay mineral (hydrous phyllosilicates). Attapulgite has a crystal lattice with a net negative charge causing the mineral to absorb cations in water or organic molecules to balance the charge deficit. The ability to bind organic and inorganic cations gives this mineral some of its special features, which led to commercial applications such as thickeners and organic sorbents.
Attapulgite gel grades are processed in a different manner than the attapulgite sorptive grades to produce very different properties from the same mineral making these products valuable in very different applications. The gel products are characterized for imparting thixotropic viscosity to liquid systems, both solvent- based and water- based. Attapulgite as a mineral is a very hydrophilic material and, therefore, able to be dispersed easily in water systems. High shear is usually desirable to obtain the best performance. for solvent-based systems, the addition of a cationic surfactant becomes necessary in order to assure proper gel development. The ratio of attapulgite to surfactant is also critical and the optimum ratio should be determined for any particular system. Gel products have found application as suspending agents and rheology modifiers for coatings, inks, adhesives, caulking compounds; animal feed supplements, wet flowable pesticides, etc. Attapulgite thickeners were compared to xantham gums in a water-based system and showed higher viscosity development efficiency and lower cost.
The sorptive grades are characterized for their capability of absorbing organic liquids and come in either granular grades or powder grades. They have infinite applications including but not limited to carrier for pesticides, wettable powders, dry flowables or water dispersible granules and filtration products.
Influence of Bauschinger Effect on Residual Stress and Fatigue Lifetimes in Autofrettaged Thick-Walled Cylinders
Authors: Parker AP , Underwood JH 
Published: March 2009

This work addresses the influence of Bauschinger effect upon residual stresses and associated fatigue lifetimes for pressurized, autofrettaged thick cylinders.The model employed allows for the variation with radius of Bauschinger Effect Factor (BEF) thoughout the autofrettaged tube since the percentage plastic strain, which determines BEF, will vary from a maximum value at the bore to zero at the elastic-plastic interface.
Accounting for BEF variability it is demonstrated that the residual compressive hoop stress at the inner radius of the tube reaches a maximum value at the percentage overstrain level below which reversed yielding does not occur. Existing experimental residual stress measurements from a variety of sources are shown to support this thesis. This value of overstrain may serve to maximize crack initiation lifetime in autofrettaged thick cylinders.
For a tube with significant heat-checking and associated initial crack-like defects it is necessary to consider fatigue crack growth rates governed by a crack growth law such as Paris' Law. For a tube of radius ratio 2.0 and at a value of approximately 40% overstrain, slightly in excess of that for the onset of reversed yielding, the fatigue lifetime exhibits a maximum value. In general fatigue lifetimes achieve a maximum value at overstrain levels in which yielding reaches 1.4 times bore radius and are almost constant thereafter. Furthermore such extended overstrain leads to a small increase in residual stress at the outside diameter (OD), thus increasing R ratio at that location and reducing fatigue lifetime for crack growth originating at the OD. Existing experimental lifetime measurements are shown to require the inclusion of BEF to properly account for these observed lifetimes.
A DNAPL Emergency Remedial Action Program in a Developing Country
Authors: Daus AD , Nobre MM 
Published: March 2009

A chlorinated hydrocarbon (CHC) manufacturing facility in northeastern Brazil inadvertently released chlorinated hydrocarbons to the subsurface. The underlying ground water lies 60 to 70 m below the ground surface and is part of a large drinking water aquifer (Barreiras aquifer). Downgradient potential receptors include local inhabitants who draw their potable water from hand-dug wells (cacimbas), wetlands, and a large estuary.
The Barreiras aquifer is alluvial in origin and consists of interbedded clays, silts, sands, and gravels. A linear geologic structure was identified at the base of the Barreiras aquifer that resembles a paleo-channel. This channel appears to correlate with the zone of highest CHC contamination.
CHCs were subsequently detected in nearby production wells 500 m downgradient. An accelerated ground-water investigation and interim remedial action plan were implemented to contain the highest CHC concentrations and provide hydraulic control downgradient of the CHC source. Ground-water production wells were installed along the paleo-channel in the alluvial sediments. Ground-water level and quality monitoring suggest that the program has been successful although additional monitoring is required to confirm the initial results. Between April 1992 and December 1993, over 1.2 billion gallons of ground water have been pumped and over 52 tons of dissolved solvents have been removed. Future plans for the project include evaluation and optimization of the ground-water capture system and evaluation of dense nonaqueous phase liquid (DNAPL) recovery.