bluuebunny/crossref_metadata_2025_split huggingface dataset:
Spray-Applied Fibrous Material Fire Resistive Coatings
Authors: Stumpf FM 
Published: March 2009

Mineral fiber compositions for spray-applied fire resistive coatings to buildings are factory mixed products consisting of manufactured inorganic fibers and proprietary binders. Air setting, hydraulic setting, and ceramic binders are used singly or in varying combinations and quantities depending on the use for which the product is designated.
The fibrous materials most commonly used for fireproofing generally range in applied density from 0.2 to 0.6 g/cm3 and range in applied thicknesses from 1.0 to 6.0 cm on decks and up to 8.0 cm on beams and columns. The spraying process is generally performed with a specially designed machine that feeds the dry mineral fiber composition to a spraying nozzle where the fiber mixture is enveloped with water as it is sprayed onto the surface to be protected. Fire resistant characteristics and other important properties such as insulation and acoustics, and resistance to air erosion and corrosion are discussed.
Evaluation of Fire Resistive Coatings Based on Small-Scale Fire Testing
Authors: Schultz N 
Published: March 2009

Economics and short-time factors have forced many manufacturers of fire resistive coatings to use small-scale fire tests in accordance with ASTM Standard Method of Fire Tests of Building Construction and Materials (E 119-81) time-temperature curve. The difference between small-size and full-size furnaces is not so much in the geometry as it is in the construction. Insulation, burners, and fuel type are influencing factors when making a comparative analysis. The American Iron and Steel Institute (AISI) used a full-size column furnace and a small-column furnace in one of their programs. The correlation between data was substantial enough to focus the attention on using the small furnace as a valid means of testing.
Within the same scenario of small-scale testing, a high intensity fire test (HIFT) is established to simulate a petroleum spill fire. It is being used by the petrochemical industry and fire resistive coating manufacturers to evaluate materials under reproducible simulated thermal conditions of a petrochemical fire.
Inspection Procedure for Field Applied Sprayed Fire Protection Materials: The Need for Standards
Authors: Erwin G 
Published: March 2009

This paper deals with the problems and the usefulness of “field inspections” of spray-applied fire resistive materials, which hopefully will develop a useful dialogue leading to the development of an ASTM standard procedure.
To date, neither ASTM Subcommittee E06.21 on Serviceability nor the manufacturers' association has been successful in advancing to an ASTM level, an acceptable procedure. The Association of the Wall and Ceiling Industries-International, working with manufacturers and other interested groups, has developed a procedure that appears to have gained some acceptance and is being used.
This paper will address methods of determining such physical and visual characteristics as substrate condition, thickness, density, bond strength (adhesion and cohesion), finished appearance, and reproducibility of ASTM Fire Tests of Building Construction and Materials (E 119-81) tested assemblies.
It is hoped that this presentation will generate interest in developing an ASTM industry standard procedure readily usable in the “field.”
Surface Acidity Distribution on Precipitated Silicas
Authors: Krivak TG , Clark M 
Published: March 2009

Precipitated silicas are carriers for a variety of formulations used in agricultural applications. In such formulations, interaction between the agricultural chemicals and the carriers must be minimized. Precipitated silicas are known to have reactive acid sites on their surfaces, which can cause catalyzed chemical decomposition. An investigation into factors that affect the acid site distribution of precipitated silicas is described in this report.
Commercially available and laboratory-prepared precipitated silicas were suspended in isooctane treated with incremental amounts of n-butylamine solution. The distribution of acid sites of different strength was determined by using six Hammett indicators, corresponding to a range of +6.8 to −8.2 pKa, in conjunction with spectrophotometric analysis of the suspensions.
Variations in blocking agents, impurities, and salt content are shown to account for alterations in the acid site distribution on the silica surface. Control of these factors will aid the agricultural formulator in minimizing chemical/carrier interaction.
Analysis of Droplet Spectra and Spray Recovery as a Function of Atomizer Type and Fluid Physical Properties
Authors: Haq K , Akesson NB , Yates WE 
Published: March 2009

Drop size, as indicated by the volume median diameter (VMD), and size uniformity, noted by the relative span (RS), were correlated with (1) viscosity, (2) surface tension, (3) viscoelasticity, and also (4) liquid throughput. Two types of nozzles were used, simple orifices or jets and hollow cones. The density of the mixtures did not vary greatly and no correlations were made with this function.
Increased liquid throughput (increased orifice diameter) showed significant effects on drop size, increasing the VMD as the orifice size increased for all nozzles and mixtures tested. Of the liquid properties, viscoelasticity had the greatest effect, increasing drop size as it was increased. Increasing the surface tension increased drop size significantly, but changes in viscosity appeared to have little effect on the drop size produced.
The RS was reduced (narrow range) as surface tension, viscosity, and viscoelasticity were increased. Increased throughput reduced RS at two surface tension levels, but when the viscoelastic polymer was used, the increased throughput actually increased the RS for the nozzles tested.
The atomization process is very complex and the study using kromkote paper collection cards could have benefited significantly if the new Particle Measuring Systems Co. (PMS) in situ system had been available. Nonetheless, the data have considerable relevance to pesticide spray atomization. Further advances will be made as the PMS or similar scanners become more widely available.
Formulation, Development, and Application of an Insecticide Granule
Authors: Synek J 
Published: March 2009

The initial development of an insecticide granule began with the choosing of a granular carrier for a turf insecticide. The physical properties and application swath width had to be acceptable to both lawn service and golf course applicators.
The properties considered important were the bulk density, dustiness, particle size, number of particles per pound or kilogram, absorptive capacity, and color. The materials evaluated as possible carriers were corncobs, vermicultie, attapulgite, montmorillonite, diatomite, and bentonite.
Bentonite was chosen as the preferred carrier for the development of the granule.
When the final formula was developed, an evaluation of various rotary and drop spreaders was initiated to measure the accuracy of the spreaders as well as the effective swath width. The number of particles per square inch and analyses were compared.
Bentonite survived all the tests and was chosen as the carrier of choice.
Probabilistic Defect Size Analysis Using Fatigue and Cyclic Crack Growth Rate Data
Authors: Trantina GG , Johnson CA 
Published: March 2009

The fatigue failure mechanism of many cast metals and high-strength alloys involves initiation and propagation of a crack from an initial defect to a critical size where fatigue failure occurs. Crack growth rate and fatigue data can be combined to estimate the initial size of the defect that led to failure. This technique has been developed and used to provide statistical interpretations of fatigue data and to determine the probabilistic size distribution of critical defects and the specimen size dependence of the average critical defect size.
An expression for the fatigue curve that incorporates the initial defect size (ai) is produced by integrating an analytical expression for the cyclic crack growth rate curve that includes a threshold stress intensity factor. For two different values of ai, two fatigue curves are generated that can represent scatter in fatigue data from two specimens of the same size or average fatigue curves for specimens with two different sizes. This scatter or specimen size effect is best treated along lines of constant initial stress intensity factor that have a slope of −0.5 on the log stress-log life fatigue curve. The separation between fatigue curves along lines of constant initial stress intensity factor is independent of fatigue life. This treatment of fatigue data therefore predicts the commonly observed trend of increasing scatter in fatigue life with increasing lifetime and provides a treatment of scatter that is independent of fatigue life.
Probabilistic defect size analysis has been applied to data for a nickel-base superalloy to predict the size distribution of critical defects. An initial defect size is inferred for each data point, then a distribution of initial critical defect sizes is predicted for the alloy. The Weibull distribution is used to display the data in terms of 1/√ai. The specimen size effect is treated where the square root of the average critical defect size increases with an increase in the effective area of the specimen. Thus, critical defect size distributions in components can be predicted that, in turn, allow material processing and inspection criteria to be based on required component life.
A Fractographic Investigation of Stress-Corrosion Cracking in High-Strength Steel Alloys
Authors: Fraser FW , Metzbower EA 
Published: March 2009

The fracture separation processes of stress-corrosion cracking (SCC) specimens of steels with yield strengths in the 700 to 1400 MPa (100 to 200-ksi) range were investigated by scanning electron microscopy. Plates from a variety of processes were tested and examined. These included the electric furnace, electroslag remelt, vacuum induction melt-vacuum arc remelt, and electric furnace-vacuum arc remelt processes. The materials were studied both in the as-received condition and after heat treatment.
Stress-corrosion cracking tests were carried out on single-edge-notched, fatigue-precracked specimens by the cantilever beam method. The specimens were fractured under stress in an aqueous 3.5 percent sodium chloride solution while galvanically coupled to zinc. The modes of fracture at the fatigue-SCC interface, in the SCC zone, and in the overload area were investigated, and a correlation was drawn between the fracture mode, the microstructure, and the resistance of the steel alloy to stress-corrosion cracking.
Fractographic and Microstructural Analysis of Stress-Corrosion Cracking of ASTM A533 Grade B Class 1 Plate and ASTM A508 Class 2 Forging in Pressurized Reactor-Grade Water at 93°C
Authors: Provenzano V , Törrönen K , Sturm D , Cullen WH 
Published: March 2009

Stress-corrosion cracking (SCC) studies were conducted in the following commonly used pressure vessel steels: ASTM A533 Grade B Class 1 (A533-B-1) plate and a fabricated forging that is equivalent in chemistry and thermomechanical processing to American-made ASTM A508 Class 2 (A508-2) forgings. The purpose of these studies was to determine the response of the materials in a simulated pressurized-water reactor environment. Round tensile specimens were bolt-loaded to 75 to 80 percent of yield and left in the water at 93°C for 2000 h. At the end of this time period, the specimens were taken out of the water, unloaded, and examined by scanning electron microscopy (SEM) and by energy-dispersive X-ray analysis. The specimen cut from A533-B-1 plate did not have any cracks as a result of the SCC tests. Several cracks, some of which were visible with the unaided eye, had developed in the specimen that was cut from the A508-2 forging. The polished and etched sections of the specimen that showed SCC, when examined with the SEM, revealed the presence of many microcracks starting from the outside surface and propagating along either inclusion-matrix or carbide-matrix interfaces; the corresponding microstructure was mostly pearlitic. The microstructure of the specimen that did not crack was bainitic; it had fewer inclusions and carbide particles, and no microcracks were observed. When the fracture surfaces of the larger cracks were examined by SEM, they revealed a cleavage-like failure propagating along inclusion bands. X-ray image scans and energy spectra of these bands showed that they were silicate and manganese-sulfide inclusions.
A hydrogen-assisted cracking model has been proposed to explain the experimental results on A508-2 forging. Produced by a cathodic reaction and aided by the stress fields, hydrogen diffuses a head of the crack tip to the inclusion sites. This causes a preferential decohesion at the inclusion—matrix interfaces and subsequent cracking along inclusion bands.
The absence of stress-corrosion cracking in A533-B-1 plate tested under identical experimental conditions is due mainly to fewer inclusion and carbide particles and to the more refined bainitic microstructure of this steel. This type of microstructure is less susceptible than the mainly pearlitic microstructure found in A508-2 forging to hydrogen-assisted cracking.
Strength Characterization and Nature of Crack Propagation in Ceramic Materials
Authors: Govila RK , Beardmore P , Kinsman KR 
Published: March 2009

A detailed study characterizing the strength and nature of crack propagation has been made in several high-temperature structural ceramics, namely, hot-pressed silicon nitride (Si3N4), Refel silicon carbide (SiC), sialons, and lithium-aluminum-silicate (LAS) glass ceramic. Fracture phenomenology was studied fractographically as a function of flaw size, temperature, and loading rate. The temperature dependence of the fracture behavior was evaluated using uncracked and precracked specimens.
All the materials showed the same general characteristics of temperature dependence of both the fracture stress and crack-growth phenomena. The only variation between the different materials was the temperature regime in which the differing phenomena occurred. Two mechanistic regimes were manifest in the temperature dependence of the fracture stress. A region of fast fracture (catastrophic crack extension) existed up to a certain temperature, in which the mode of crack propagation was primarily transgranular. Above this temperature, the strength (fracture stress) decreased considerably due to the presence of subcritical or slow crack growth (SCG) prior to the final catastrophic fracture, and the extent of SCG increased with increasing temperature. Slow crack growth is a result of microplastic deformation, which occurred by grain-boundary sliding and grain separation, and the mode of crack propagation is exclusively intergranular.
The influence of the loading rate on SCG and fracture stress was investigated. Generally, at a given temperature, the extent of SCG decreased with increasing loading rate until, at a sufficiently high rate, catastrophic fracture occurred directly from the initial crack with no slow crack extension. Directly analogous observations were made in stress-rupture studies in which the extent of SCG decreased with increasing stress level.
A Nondestructive Method of Evaluating Adhesive Bond Strength in Fiberglass Reinforced Plastic Assemblies
Authors: Chapman GB 
Published: March 2009

Two parameters used to quantify the nondestructive inspection (NDI) of adhesive lap-joint bonds are useful as reliable indicators of adhesive bond strength in certain inspection applications. The two indicators, local bond integrity index (LBI) and bond merit factor (BMF), will be defined and their relationships to bond strength demonstrated and discussed.
The LBI indicator is obtained from readings of local bond integrity made with a commercially available bond tester. The readings were made on local bond regions approximately 2.5 cm2, with a bond tester that had been calibrated to a desired sensitivity by using an appropriate reference specimen. The reference specimen was selected by a simple statistical and physical test procedure, and its use provides a reproducible relationship between LBI and bond strength. Destructive test results have shown good correlations (r = 0.9) of lap-shear strength with LBI readings for a given sample set.
The BMF indicator is an easy-to-obtain, time-efficient indicator of adhesive bond coverage. It is computed for a bond line region, generally 15 to 40 cm long, using disbond detection data obtained for instrument sensitivity based on the LBI of the reference specimen. These regional inspection results have shown fair correlation (r = 0.7) with the sum of local lap-shear strengths over the region.
Estimating the Acute Toxicity of Narcotic Industrial Chemicals to Fathead Minnows
Authors: Veith GD , Call DJ , Brooke LT 
Published: March 2009

The overwhelming number of industrial chemicals either in commerce or in development precludes actual toxicity testing of each chemical and creates a need for initial screening techniques to focus efforts on those chemicals with the greatest potential for adverse environmental effects. One promising screening technique is the use of the structure-activity relationship to estimate aquatic toxicity from chemical structure.
Using five major classes of industrial chemicals from the Toxic Substances Control Act (TSCA) inventory, this paper presents a structure-activity relationship between the 96-h LC50 with fathead minnows and the n-octanol/water partition coefficient which can be computed from structure. Common industrial alcohols, ketones, alkyl halides, ethers, and benzenes are shown to cause lethality by the same mode of action of narcosis. Consequently, a single bilinear equation can predict adequately the 96-h LC50 of all classes of industrial chemicals to fathead minnows.
Fate and Effects of 5-Nitrofuroic Acid-2 (NFA) on a Marine Plankton Community in Experimental Enclosures
Authors: Kuiper J 
Published: March 2009

The fate and effects of a single dose of 0.3 and 1.0 mg of 5-nitrofuroic acid-2 (NFA) per litre on a marine plankton community enclosed in large plastic bags (contents 1.5 m3) were studied. The plankton community was derived from North Sea coastal waters, and the model ecosystems were anchored in the harbor of Den Helder, the Netherlands, where they were exposed to a natural light and temperature regimen. Two experimental units were polluted with NFA; a third served as a control.
During four weeks the development of the phytoplankton, zooplankton, and bacteria was followed, as were a set of physicochemical parameters including nutrients, light, and temperature.
The nitro group was removed from the NFA within about one day of the addition of the compound to the model ecosystems, probably as a result of the exposure to light. The intact NFA inhibited the phytoplankton slightly; the remaining molecule produced no detectable effects in the system. The development of the enclosed community was very similar in the different bags.
Environmental Assessment of a Phthalate Ester, Di(2-Ethylhexyl) Phthalate (DEHP), Derived from a Marine Microcosm
Authors: Perez KT , Davey EW , Lackie NF , Morrison GE , Murphy PG , Soper AE , Winslow DL 
Published: March 2009

This study tested the influence of system complexity on the environmental assessment of a chemical. Marine microcosms were perturbed with a phthalate ester, di(2-ethylhexyl) phthalate (DEHP).
Concentrations of 1, 10, and 100 µg of DEHP per litre were added to the water-column subsystem of marine microcosms for 30 days during the summer (18°C) and winter (1°C) seasons. Significant portions of the DEHP losses from the water-column subsystem during the experiments were due to the complete breakdown of the parent compound to carbon dioxide (CO2). In the benthic subsystem, DEHP concentrations in the sediment were increased by more than 50 and 250 times the concentration in the water column during the winter and summer seasons, respectively. Statistically significant (α = 0.05) reductions in the fluxes of ammonia (NH3) from the benthic subsystem were observed in microcosms receiving 100 µg of DEHP per litre during the summer. Concentrations of DEHP in selected bivalves ranged from 174 to 229 000 µg of DEHP per wet kilogram, depending upon the water column exposure concentrations and the season of the year.
Effects of Increasing Levels of Primary Production on Pentachlorophenol Residues in Experimental Pond Ecosystems
Authors: Robinson-Wilson EF , Boyle TP , Petty JD 
Published: March 2009

The magnitude of primary production may influence the degradation and bioavailability of contaminants in aquatic ecosystems. The rate at which these contaminants degrade is important in considering the toxicity and ultimate effect and fate of the chemicals. The degradation and fate of pentachlorophenol (PCP), a biocide and common contaminant, was studied in replicate pond ecosystems at three levels of primary production: (1) low-nutrient phytoplankton ecosystems (low primary production), (2) high-nutrient phytoplankton ecosystems (medium primary production), and (3) macrophyte-dominated ecosystems (high primary production). The PCP treatments were of two types: (1) a single heavy treatment (1 mg/L) applied early in the experiment and (2) multiple treatments of 0.2, 0.2, 0.4, and 0.4 mg/L applied at monthly intervals.
The concentrations of PCP in water and mud were consistently lower in the macrophyte pond group than in the phytoplankton pond groups. The difference between the amount of PCP in the phytoplankton ponds and that in the macrophyte ponds were not apparently due to sorption onto the macrophytes. Therefore, the macrophytes were either actively degrading the PCP or incorporating it into their structure in a form that was not extractable. PCP residues in fish also reflected the lower bioavailability of PCP in the macrophyte ponds. Both the total PCP and the concentration of PCP in fish from the macrophyte ponds were lower than those for either of the phytoplankton pond groups. High primary production rates appear to increase the degradation rate of PCP in pond ecosystems.
Role and Application of Semicontrolled Ecosystem Research in the Assessment of Environmental Contaminants
Authors: Boyle TP 
Published: March 2009

The procedures for assessing the toxic effects of potential environmental contaminants are hierarchical, being composed of the following four sequential steps: (1) single-species acute and chronic toxicity tests, (2) tests of ecological interactions with simple communities in laboratory microcosms, (3) experiments on chemical-induced changes in ecosystem structure and function, in which replicate pond and artificial stream ecosystems are used, and (4) use of techniques for assessment of the actual impact of the contaminant on natural ecosystems.
Experiments involving semicontrolled artificial ecosystems in ponds and streams are carried out over the course of one or two years to identify the magnitude of (1) the primary direct effects of contaminants on the principal elements of the biological community and (2) the secondary or indirect effects of stress due to changes in critical structural or functional variables of the ecosystem. The results from ecosystem-contaminant studies can be used to establish the applicability of laboratory bioassays, to examine the qualities that enable ecosystems to resist contaminant stress and recover from it, and to answer questions on the effect of long-term stress of chemicals with herbicidal or insecticidal properties.