bluuebunny/crossref_metadata_2025 huggingface dataset:
Cyclic Behavior of A1319-T7B Under Isothermal and Non-Isothermal Conditions
Authors: Engler-Pinto CC , Sehitoglu H , Maier HJ
Published: April 2008

The use of cast aluminum alloys for automotive components has greatly increased in the past two decades due mainly to the lower density and increased thermal conductivity of aluminum alloys as compared with cast iron. A unified constitutive model is developed for the aluminum alloy A1319 under T7B thermal treatment. The model is based on two state variables: the drag stress and the back stress. The constants for the model were determined systematically from isothermal experiments and the capabilities of the constitutive model were checked by comparing the simulations with isothermal and thermo-mechanical experiments. The results show that the model provides successful simulations for the material response over a broad range of temperatures and strain rates, including cyclic softening and thermal recovery.
Thermo-mechanical Creep-Fatigue of Coated Systems
Authors: Rémy L , Alam AM , Bickard A
Published: April 2008

This paper presents an investigation of the damage mechanisms in protective coatings deposited on a single crystal superalloy, under TMF (thermo-mechanical fatigue) loading conditions. This includes an aluminide coating called C1A and a Thermal Barrier Coating (TBC). Different TMF cycles are used to assess the coating resistance in both cases and respective damage mechanisms are reported. TMF cycles derived from real service conditions prove to be better testing methods for coating resistance as compared to standard cyclic oxidation tests without mechanical loading. Implications for lifing procedures are tentatively discussed from the results of this investigation.
Improving the Reproducibility and Control Accuracy of TMF Experiments with High Temperature Transients
Authors: Brendel T , Naderhirn M , del Re L , Schwaminger C
Published: April 2008

Three different approaches to minimize control deviations in the case of TMF experiments with high temperature transients (10K/s and higher) will be presented. In the first approach, an empirically derived algorithm is used to calculate a modified temperature command function based on the recorded control deviations. In a second approach, a two-zone model of the plant (specimen, grips, heating and cooling device) is used for control design. The model is first used to design a “soft” PI controller for generating a robust starting output profile. This output profile is then used as a basic reference input profile. The remaining error is minimizes by a “fast” PI controller. A third controller approach is characterized by the determination of an inverse model that is used to define an “ideal” profile of the command variable. This “ideal” profile is then used as a reference input profile.
Fire Tests for Non-Melting Plastic Rooflight Materials
Authors: Khan MM , Alpert RL , Smith GA
Published: April 2008

A dimensionless “flame acceleration factor” (FAF) based on an existing concurrent flame spread model that includes consideration of fuel burnout, has been used to evaluate the flame spread on thin rooflight (or skylight) materials. The FAF is a function of ignition time, burning duration and chemical heat release rate obtained from bench-scale tests in the ASTM E-2058 Fire Propagation Apparatus (FPA). A direct correlation between the FAF values and the extent of flame spread over eighteen thin polymeric rooflight materials (1.0–3.3 mm thick and 1.4–4.0 kg/m2 areal density) measured in large-scale tests in the ASTM E108 Test Apparatus has been presented in this paper. In accordance with the model prediction, the flame spread remains within the propane burner flame exposure region in E-108 tests when FAF < 0. Flame spread is distinctly beyond the exposure source when the FAF > 0, except for the case of some extensive melting thermoplastics. This model does not take the melting phenomenon into account.

A calculation procedure for safe separation distances for rooflights that support flame spread has been developed. These separation distances are based on chemical heat release rate, critical heat flux for ignition and smoke yield of the material as measured in the FPA, the length of rooflight that is burning at any given time and the flame height, and overall dimensions and orientation of potential rooflight targets. The calculated safe separation distance is found to be greater than one-half the total flame height.
A Realistic Approach for Testing the Thermal Insulation Value of Closed-Cell Spray Polyurethane Foam Roof Insulation
Authors: Sherman M , Mullally W , Garcia J , Dobrez-Flores D
Published: April 2008

The thermal resistance characteristics of thicker closed-cell spray polyurethane foam insulation products appear to be understated when tested at one inch thickness as required in ASTM C1O29-96 [1]. This results in excessive and costlier foam thicknesses being prescribed to meet a specifier's R-value requirements than if full product thickness conditioning before full product thermal resistance testing had been specified.

Confirmation of this concern was studied by the Building Envelope Committee of the Spray Polyurethane Foam Alliance, measuring full product thickness thermal resistances after the 180 days conditioning time. Three commercially marketed proprietary closed-cell spray polyurethane foam formulations containing HCFC 141b blowing agent were tested.

All three formulations affirmed the concept of measuring full product thickness thermal resistance after time conditioning. Increasingly thicker spray polyurethane foam specimens retained more of their initial thermal resistance values after the standard 180 days of time conditioning before testing, than if thermal resistance values measured on one inch thick spray foam specimens multiplied by the full product thickness, were used for extrapolating these thicker product thermal resistances, as done with homogeneous thermal insulations.
Durability and Cold Temperature Performance of SBS-Modified Bituminous Roofing Membranes
Authors: Liu K , Xu G , Voyer R
Published: April 2008

The National Research Council of Canada, in collaboration with a Canadian roofing manufacturer, conducted an experimental program to evaluate the durability of SBS-modified bituminous roofing membranes in Canada. This study examined the effect of heat aging on the mechanical and chemical properties of nine commercially available SBS-modified membranes, with emphasis on cold temperature performance. These membranes varied in reinforcements and densities, and were selected to be representative of SBS-modified membranes currently used in Canada. The membrane samples were heat aged in convection ovens at 70±3°C for six months. During this process, some samples were withdrawn at two-month intervals and their tensile properties at 23°C and -30°C, cold flex temperature and glass transition temperature determined. The results confirmed that heat aging mainly affected matrix-controlled properties of the membranes. In addition, the reinforcement controlled the mechanical properties at 23°C but the modified bitumen governed the failure mechanism at -30°C for the polyester reinforced membranes.
Durability Study for Geotextile Tube Use in Talimu River Sediment Control
Authors: Chang DTT , Sung CP , Chen BL , Ho NH
Published: April 2008

To rebuild dikes for Talimu River regulation project, insitu sediments is considered to be contained by geotextile tube ( geotube ) for use as dike core. Stress analysis and matrix shape analysis are required to determine the geotube size. Based on experience and the local climatic conditions of Xing Jiang, China, durability of the geotubes is considered the most critical factor for sediment control. The geotube material used in this study is woven geotextile made in Taiwan — GTM-1 and GTM-2. The tests were conducted in accordance with ASTM Test Method (D 4355) for deterioration of geotextiles from exposure to ultraviolet light and water. After UV exposure for 200 and 500 hours, the results showed that the residual tensile strengths of the geotextiles are greater than 90 % and 70 % of the ultimate tensile strength, respectively. More results showed that reduction in tensile strength is insignificant even after UV exposure for over 600 hours. Another durability test is the geotextile's resistance to freezing and freeze-thaw cycles. Initially the geotextiles were placed in a temperature chamber and cured at -20 °C, -30 °C, -40 °C for 6 days. The results showed that the geotextiles still retained greater than 90% of its ultimate tensile strength. For the freeze-thaw cycles (-40 °C–40 °C, -10 °C–20 °C), results also indicate that the selected geotextiles provide good freeze-thaw resistance.
Numerical Model for Contaminant Transport in Consolidating Sediments
Authors: Fox PJ
Published: April 2008

A numerical model for coupled, one-dimensional, large strain consolidation and contaminant transport, called CCT1, is presented. The large strain consolidation algorithm includes all the capabilities of a previous code, CS2. The contaminant transport algorithm includes advection, dispersion, and linear equilibrium sorption with a spatially varying distribution coefficient. Advection-dispersion transport is consistent with spatial and temporal variations of porosity and seepage velocity in the consolidating layer. The key to the transport model is the definition of two Lagrangian columns of elements that follow the motions of the fluid and solid phases separately. Verification checks of CCT1 show excellent agreement with analytical solutions for classical transport problems involving advection, diffusion, dispersion, and sorption in rigid porous media. The performance of CCT1 is illustrated for an example problem involving consolidation-induced transport of a dilute contaminant species in a soft sediment layer.
Assessment of the Lead Release from Cables Buried in Sediments into the Water Column
Authors: Degtiareva A , Elektorowicz M , Ebadi T
Published: April 2008

The study investigates the change in the water column quality in a situation where submarine communication cables cross the water bodies. In spite of precautions in technological achievements it is possible that these cables can be subjected to potential corrosion processes. This study was performed for a particular area of the St. Lawrence River. The impact of cables buried in sediments on lead speciation in the water column was shown under different conditions (anaerobic and aerobic, at different partial pressures of CO2, presence of organic acids). Equilibrium in the water was calculated taking into account gas, water and solid phases. Programs Equilibrium and EPH from FACT were utilized in this study to calculate Eh-pH diagrams and the equilibrium in water. The main form of lead was found to be PbOH+ (3.34×10-9 M/kg), the concentration of the free lead ion was two orders of magnitude lower (2.5×10-11 M/kg). The calculations, in which solid phases where considered, demonstrated that the water was oversaturated with respect to dolomite and iron(III) hydroxide. It was speculated that under these conditions dolomite could form a protective layer around the cable, which can delay the corrosion. Under anoxic conditions cerussite and lead sulfide precipitated. When PCO2 increased, the concentration of the free ion of lead increased.
Toxic Combustion Products Testing of Polymers Used in Oxygen Systems A Review of Testing at WSTF
Authors: Hshieh FY , Hirsch DB , Beeson HD
Published: April 2008

This paper reviews some of the toxic combustion products testing, in ambient pressure, previously performed at NASA White Sands Test Facility (WSTF). The paper also presents some results from recent toxic combustion products testing in high-pressure oxygen of polymers typically used in oxygen systems. The review shows that generation of combustion toxicants is both material-dependent and temperature (or fire)-dependent. Fire conditions, the location and means of sampling, and analytical instruments used are the controlling parameters for the analysis of toxic combustion products. FTIR can provide continuous, real-time measurements of combustion product gases; however, it is difficult to obtain quantitative FTIR measurements. Appropriate sampling probe, filters, gas transfer line, and FTIR software are definitely needed. Nondispersive infrared (IR) is an effective tool for real-time carbon monoxide and carbon dioxide measurements. Combustion products analyzers (electrochemical method) and Draeger® Tubes are limited to the analysis of light combustion product gases, and they are less efficient compared with FTIR. The results of combustion testing in high-pressure oxygen environments show that combustion of polymers in high-pressure oxygen environments generated much less carbon monoxide and hydrogen cyanide. The toxic potency of the combustion gas is presumably lower than that of combustion gas generated from ambient-pressure oxygen (or air) environments.
Modeling the Ignition of Large Diameter Rods and Pipes in Flowing Oxygen
Authors: Maes MJ , Forsyth E , Wilson DB , Stoltzfus JM
Published: April 2008

The recent Industry-Sponsored Metals Combustion Test Program (96-1) involved promoted-ignition and burning of 316L stainless steel rods (1.27 cmdiameter) and Sch. 80 and XXS pipe (11/4 in. nominal diameter) in both static and flowing oxygen. These tests demonstrated difficulties igniting large samples in flowing oxygen. This work examines and models the ignition of metals based on the Standard Test Method for Determining the Combustion Behavior of Metallic Materials in Oxygen-Enriched Atmospheres (ASTM G124) configuration test. Appropriate mass and energy conservation balances are developed and validated against the experimental results of Phase I and II tests. Parametric studies demonstrate the effects of system pressure and flow on ignition. These results are compared to current theories of ignition, and future work is suggested.
Failure Analysis of Fires in Oxygen Production Process Valves
Authors: Beeson H , Ginter J , Dobbin D , Forsyth E
Published: April 2008

The NASA Johnson Space Center (JSC) White Sands Test Facility (WSTF) as requested to perform failure analyses on damaged hardware from a series of fires that occurred in an oxygen production process (OPP). The purpose of the analysis was to determine the cause of the fires, which occurred in five valves in separate incidents in two different applications. The approach of the analysis was to understand the system configuration and operation, review the fire scenario, and analyze the system for possible ignition mechanisms. The evidence was reviewed and analyzed using microphotography and macrophotography, scanning electron microscopy, and chemical analysis. The evidence was then used to prove or disprove various failure scenarios. This paper reports the analysis results and provides recommendations for improving the system's resistance to ignition and combustion.
Oxygen Fire Cause and Origin Analysis of the CUMA V2 Underwater Breathing Apparatus
Authors: Forsyth ET , Eaton DJ , Newton BE
Published: April 2008

The Canadian Underwater Mine-countermeasures Apparatus (CUMA) is a self-contained, semi-closed circuit underwater breathing apparatus used by the Canadian Forces for underwater mine search, investigation, and disposal. On November 30, 2001, the Experimental Diving Unit staff at Defence Research and Development Canada — Toronto was preparing for an experimental dive using the CUMA Version 2 (V2) in their facility's hyperbaric chamber. A fire occurred in the CUMA V2 as the Team Leader (diver wearing the CUMA V2) opened the oxygen sphere valve. The fire was severe, ejecting fire and molten metal for a distance of approximately 7 feet from the diver's back-mounted unit, and lasting for an extended duration before the diver's teammates were able to remove the backpack and extinguish the fire. No one was seriously injured in the incident. Wendell Hull & Associates, Inc. (WHA) was contracted to investigate the oxygen fire, specifically to perform a cause and origin analysis, and to provide recommendations for the CUMA V2 oxygen system to improve its ignition resistance and fire tolerance. WHA reviewed the incident details, system components, materials of construction, and operational procedures and conditions. WHA also inspected the burned hardware and disassembled individual components as required to characterize the burn and melt-flow patterns. Key materials were sampled as required and chemical analyses on samples were done to obtain positive material identification. The evidence is consistent with the local origin of the fire being within the first-stage regulator close to the non-metal seat. The evidence also indicates that operationally induced ignition mechanisms and incompatible materials were causative factors in the ignition and propagation of the fire. This paper describes the events of the oxygen fire incident, the protocol used to analyze the fire's cause and origin, and the results of the analysis. The recommendations to improve CUMA V2's ignition resistance and fire tolerance are also discussed.
The Values of Coaches and Players About Rule Infractions, Violence, and Ethics
Authors: Bernard D , Trudel P
Published: April 2008

Studies on moral education in sport suggest that a sport like ice hockey which is a competitive male contact sport is an excellent context to study values and moral education. Using an ethnography approach, the researcher followed the activities of a Bantam (14–15 years) AA team during an entire season. Among the data collected are interviews with the head coach and some players (n=8) on 10 specific events that happened during the season and were recorded on videotape. Analysis of the interview transcripts shows similarities in the players' and coach's comments. The analysis also confirmed the presence of a subculture where (a) the opponent should be viewed as an enemy, (b) there is no respect for the opponent and (c) in certain situations players must infringe upon the rules. The actual practice of ice hockey does not provide youth hockey players with opportunities to acquire moral values that will make them better citizens.
Body Checking and Serious Injury in Ice Hockey: A Technical and Behavioral Assessment
Authors: Juhn MS
Published: April 2008

Body checking in ice hockey is considered a fundamental and essential component of the game in the eyes of many involved in the sport. While some find body checking entertaining, it has also been criticized for glorifying violence and causing many serious injuries. An analysis of the literature shows that it is the illegal body checks (such as checking from behind), as well as checks to the head (legal in some leagues), that result in the most serious injuries. Illegal checking must be punished more severely with an automatic additional game suspension, rather than a case-by-case assessment. The present penalty system in most leagues has not curtailed the incidence of illegal checking, but more severe punishment which includes automatic additional game suspensions would likely be more effective. The problem must also be addressed at the grass roots level by recognizing the critical importance of proper coaching. Strict enforcement of facial protection and consideration of larger rink size for more playing room may also help reduce serious injury. Age restrictions on allowing body checking have been suggested due to size differences between players, but there exists no evidence that injuries in ice hockey are the result of larger players checking smaller players. Still, the concerns of playing a contact sport in the developing athlete is not without merit. It must be emphasized that body checking is an acquired skill that should be taught in a developmental fashion. It is not only the techniques of body checking, but also the attitude towards checking, that must be properly taught.
The Effects of an Upper-Body Plyometrics Program on Male University Hockey Players
Authors: Fergenbaum MA , Marino GW
Published: April 2008

The relationship between plyometrics training, upper-body isometric strength, stick velocity and puck velocity for the slap shot was examined for male university hockey players over 10 weeks. Twenty-one volunteers were divided into either an experimental or a control group. The experimental (plyometrics) group was pre- and post-tested for upper-body isometric strength and slap shot puck and stick velocity. Results showed that puck velocity increased (p<0.05) from pre- to post-testing, with no differences between groups. Stick velocity increased 13% (p<0.05) for the experimental group at post-testing. No significant correlations were found between isometric strength, stick velocity and puck velocity; however, a positive correlation was found between changes in stick velocity (off-ice) and changes in puck velocity (on-ice). Results suggest that plyometrics may improve ballistic coordination between the upper and lower limbs in as little as 6 ± 2 sessions.
Endpoint Verification of Bone Demineralization for Tissue Engineering Applications
Authors: Thomas CB , Jenkins L , Kellam JF , Burg KJL
Published: April 2008

Demineralized bone matrix is used in tissue engineering applications due to its ability to promote new bone formation. Numerous processing variables, such as the degree of demineralization, can affect the matrix's bone-forming ability. Several methods exist for determining the extent of demineralization, but each method has disadvantages. This study investigated the potential use of a stereomicroscope in determining the degree of demineralization by comparing the novel technique to two conventional methods. Bone fragments were processed and demineralized using a standard protocol, and their degree of demineralization was characterized over time by the three methods. The results indicate that a stereomicroscopy method is as effective as two established methods in verifying the degree of demineralization.
Development of Standards for the Characterization of Natural Materials Used in Tissue Engineered Medical Products (TEMPs)
Authors: Kaplan DS
Published: April 2008

ASTM Committee on F4 Medical and Surgical Materials and Devices, Division IV, Tissue Engineered Medical Products (TEMPs), Biomaterials and Biomolecules for TEMPs Subcommittee (F4.42) has been developing standards for characterizing natural materials used in TEMPs. Natural materials include alginate, chitosan, collagen and hyaluronate. These materials support cell growth and differentiation on TEMPs substrates and scaffolds. Natural materials have been used in a variety of applications, including encapsulation, cell seeding, development of “memory” biomaterials, as well as degradable scaffolds, growth factor/nucleic acid delivery vehicles, and as a carrier to improve product handling characteristics. These materials have typically been very poorly characterized as to their chemical, physical and biological properties. This has resulted in variability in the products produced from these starting materials. The development of Standard Guides and Test Methods for characterizing natural materials is anticipated to reduce the variability of these starting materials and to aid in the assessment of the safety of the subsequent TEMPs.

Three Standard Guides for characterizing the natural materials that are used as starting materials in the production of TEMPs have been developed and approved as ASTM standard guides. The first guide deals with Alginate, while the second guide deals with Chitosan and Chitosan salts. A third guide was recently approved for the characterization of Type I collagen used for surgical implants and substrates for TEMPs. Standard test methods are under development for the use of 1H-NMR to determine the molecular weight of alginate and the degree of deacetylation of chitosan.

Planned future documents will include guides to characterize additional types of collagen and hyaluronate, as well as the development of additional standard test methods for characterizing the natural materials.
SED Method of Measuring Yield Strength of Adhesives and Other Materials
Authors: Lenwari A , Albrecht P , Albrecht M
Published: April 2008

The strain energy density (SED) method of determining the yield strength of adhesives and other materials that is based on the fundamental principles of mechanics is described in this paper. The results from two sets of tests are reported. In the first set, the yield strength of multiple specimens made of the adhesive FM 300K was determined in the dry/cold, moderate, and humid/hot environments; the strain rates were 10-2/s, 10-4/s, and 10-6/s. In the second set, single specimens of five other adhesives were tested in the dry/cold and humid/hot environments; the strain rate was 10-4/s. Fifty-three out of the 60 specimens have yield strengths calculated with the SED method that are equal to or lower than the values obtained with the 0.2 % offset method suggested in the ASTM specifications. The SED method is most valuable when the stress-strain curve of the material exhibits a gradual transition from elastic to the inelastic behavior typical of polymers, aluminum, and some very high strength steels. To ensure the safety of bonded structures, the yield strength of adhesives should be determined with the SED method, which is based on the fundamental principles of mechanics, instead of on an arbitrary estimate of strain offset. Although applied in this paper to stress-strain curves of adhesives, the SED method may also discern the onset of yielding and instability in columns and beams. To ensure that the yield strength of adhesives for bonding load-bearing structures is not systematically overestimated, the authors recommend using the SED method in lieu of the 0.2 % offset method.
Interfacial Diffusion of Fluids in Pressure Sensitive Adhesives
Authors: O'Brien EP , Ward TC
Published: April 2008

Diffusion of acetone at the interface of a bonded pressure sensitive adhesive tape was measured using single frequency capacitance measurements (SFCM) and a novel interdigitated electrode sensor design. The relative concentration of acetone at the bondline as a function of distance from the edge of the specimen and exposure time was correlated to adhesion loss measured by the 90° peel test. This work suggests that these novel sensors are applicable for the study of interfacial diffusion processes. and could be extended to other coatings or adhesives in a variety of environments.
Advanced Methods of Coating Adhesion Testing
Authors: Gitis NV , Xiao J , Vinogradov M
Published: April 2008

Adhesion of coatings from 1 nm to 0.1 mm was successfully evaluated with multi-sensing technology, based on simultaneous high-resolution force, electrical, and acoustic measurements. Sharp changes in the signals were indicative of the thresholds of adhesion and delamination for various thin and thick coatings during scratching and indenting with several test tools. both sharp (diamond tips) and dull (balls).
The Sensitivity of Crosslinked UHMWPE to Abrasive Wear: Hips versus Knees
Authors: Good VD , Widding K , Scott M , Jani S
Published: April 2008

All formulations of commercially available highly crosslinked ultra-high molecular weight polyethylene (UHMWPE) have demonstrated dramatic reduction in wear compared to conventional UHMWPE. A majority of these demonstrations have been under “smooth,” i.e., non-abrasive conditions. The question, therefore, remains: are contemporary highly crosslinked UHMWPE (XPE) materials suitable for both hips and knees under abrasive conditions in vivo? These studies examined both XPE (10Mrad, GUR1050) and non-irradiated UHMWPE (GUR1050) for hips and knees under smooth and abrasive conditions. Studies were conducted on a 12-station hip and 6-station knee simulator. The femoral components were left polished or tumbled with plastic cones and alumina powder to create uniform scratching with surface roughness similar to clinical retrievals. In smooth conditions, XPE wore significantly less than non-irradiated UHMWPE (CPE) for both hips and knees. In abrasive conditions, wear of XPE increased by at least 15 times in hip applications and at least 70 times in knee applications. Furthermore, XPE knees wore more than CPE knees in the abrasive condition. This study showed that both forms of UHMWPE were subject to accelerated wear under abrasive conditions; however, the sensitivity of XPE to abrasive wear was greater for knees than for hips. These findings need to be taken into consideration when developing materials for improved wear resistance in knees.
Population Dynamics in Spatially and Temporally Variable Habitats
Authors: Andersen MC
Published: April 2008

Populations live in habitats whose quality varies spatially and temporally. Understanding how populations deal with these variable habitats can aid our understanding of theoretical issues, and practical issues of biological invasions and biodiversity conservation. I investigate these issues by superimposing simple models of population growth and dispersal on spatiotemporally fractal landscapes, and examining the properties of the landscapes, and of the populations inhabiting them. The properties of the simulated landscape sequences are comparable to those of real habitats. The simulated populations exhibit a range of dynamic behaviors; these behaviors are strongly influenced by the fractal parameters of the landscapes. The results may help explain several important phenomena seen in reintroductions of threatened and endangered species, introductions of biological control agents, and biological invasions. These phenomena include frequently observed lags between population introduction and initial population growth and spread, and the observed high frequency of failure of introductions.
Estimating Receptor Sensitivity to Spatial Proximity of Emissions Sources
Authors: Reshetin VP
Published: April 2008

The term of the receptor sensitivity of a territory to siting accommodation of mission sources can be effectively calculated by means of a mathematical apparatus of conjugate problems. Solutions of conjugate equations make it possible to determine the effect of pollution in the form of aerosols or harmful gaseous impurity on the environment and human health. Examples of calculation of the sensitivity term by solving a conjugate problem are given. Mathematical models for typical problems of optimal siting of enterprises are formulated and interpretation of the results obtained is given.
Rapid Set, High-Early Strength, Non-Excavatable Flowable Fill
Authors: Crouch LK , Dotson VJ , Clouse L , Egan B , Hall SM
Published: April 2008

A high-flow, rapid-set, non-excavatable CLSM mixture called ZOOM was developed for applications where time was critical using normal concrete component materials. The following criteria were established for the ZOOM mixture: • Pass the ASTM D 6024 in 6 h or less regardless of subgrade moisture conditions • Little or no bleeding or shrinkage • Flow as per ASTM D 6103 greater than 222 mm • Greater than 207 kPa compressive strength as per ASTM D 4832 in 24 h • Be able to perform using a wide variety of Tennessee aggregates

The development of the ZOOM mixture began in the laboratory in May 2002 using Ohio River Sand (ORS). Subsequently, the mixture proportions were adjusted to produce the desired plastic and hardened properties with other Tennessee fine aggregates. Three successful field demonstrations using different fine aggregates were held across Tennessee in the fall of 2002. ZOOM CLSM met compressive strength development and time of suitability for load application performance criteria at every field demonstration.Plastic properties were adequate but failed to meet the established criteria on two occasions. Fine aggregate properties such as gradation and angularity were found to dictate mixture proportions required to achieve flow, air content, and bleeding characteristics. Average air temperature and CLSM air content were found to be important to time of suitability for load application. The research effort was co-sponsored by the Tennessee Department of Transportation and the Tennessee Ready Mixed Concrete Association
Methods for Field and Laboratory Measurement of Flowability and Setting Time of Controlled Low-Strength Materials
Authors: Tripathi H , Pierce CE , Gassman SL , Brown TW
Published: April 2008

Flow consistency and setting time are two important properties of controlled low-strength materials (CLSM). This paper describes and evaluates several standard and non-standard methods to measure these properties. Several mixtures with a range of water-to-binder ratios were investigated through a series of field and laboratory experiments. A linear relationship was observed between the flowability measured by the flow cylinder method (ASTM D 6103) and the inverted slump cone method.Pocket penetrometer and Torvane measurements were compared to the Kelly Ball method (ASTM D 6024) for estimating sufficient bearing capacity. Pocket penetrometer resistance correlates well, but its capacity was often exceeded. Volume stability should be controlled to avoid softening of the surface and subsequent delays in measured hardening time.
Long Term Study of 23 Excavatable Tennessee Flowable Fill Mixtures
Authors: Crouch LK , Dotson VJ , Badoe DA , Maxwell RA , Dunn TR , Sparkman A
Published: April 2008

Twenty-three different EFF mixtures were placed in trenches simulating utility cuts during March through May of 2001. All EFF mixtures were tested for flow, unit weight, gravimetric air content, suitability for load application, and compressive strength development over time. The trenches were excavated in March 2003. Excavation difficulty was correlated with laboratory compressive strength for non-air-entrained mixtures. Bearing capacity estimates with the dynamic cone penetration apparatus were determined for all trenches. Nine EFF mixtures were used to assess the impact of Portland cement content and ASTM C 618 Class F fly ash content. Portland cement contents of 17.8, 26.7, and 35.6 kg/m3 and ASTM C 618 Class F fly ash contents of 178, 219.5, and 261 kg/m3 were used to evaluate the impact of component proportions. Proportions for the EFF mixtures were chosen using Kentucky Transportation Cabinet and Tennessee Ready Mixed Concrete Association (TRMCA) recommendations as well as a previous Tennessee Technological University research mixture. Six EFF mixtures were used to assess the impact of Portland cement content and high-unburned carbon fly ash content Portland cement contents of 26.7 and 35.6 kg/m3 and high-unburned carbon fly ash contents of 219.5, 261, and 302.5 kg/m3 were used to evaluate the impact of component proportions. The influence of aggregate type on EFF mixtures was evaluated by using five different aggregate types in the EFF mixture recommended by TRMCA (26.7 kg/m3 Portland cement and 219.5 kg/m3 ASTM C 618 Class F fly ash). In addition, four comparison EFF mixtures were also used in the study (1 Tennessee Department of Transportation (TDOT) and 3 air-entrained EFF mixtures).
Benefits of a 2,4-D Acid Herbicide Formulation
Authors: Volgas GC , Mack RE , Roberts JR
Published: April 2008

Research was conducted on a new formulation of 2,4-dichlorophenoxy-acetic acid (2,4-D). Unlike many of today's commercial products that contain ester or amine forms of 2,4-D, this new formulation contains the acid form of 2,4-D. Comparisons of this new formulation with amine and ester formulations include herbicide efficacy data, surfactant properties, and fertilizer compatibility.
Agricultural Granule Particle Size Considerations
Authors: Goss GR
Published: April 2008

When developing a granular pesticide formulation, the choice of an appropriate particle size is crucial. Particle size may or may not affect the desired performance parameters. Some of the properties to consider are sorptivity, bulk density, particle count per unit weight, hardness, drift potential, and application pattern. Depending on the nature of the carrier, particle size has little effect on bulk density and sorptivity. Particle size affects particle count per unit weight, drift potential, and possibly application pattern.
Applications of Ether Amine Surfactants in Agricultural Formulations: The Known and Unexplored
Authors: Lei Y
Published: April 2008

Ether amines, ether amine alkoxylates, and their derivatives have found increased use as agricultural surfactants in the past decade. Most of the documented applications of ether amine surfactants have been limited to glyphosate formulations, where ether amine ethoxylates, oxides, and quats have been demonstrated to be excellent adjuvants. Because of regulatory status and availability, their application potentials in agricultural formulations have not been fully explored. In this paper, we will review the unique physical properties of ether amines and amine ethoxylates and their applications as agricultural adjuvants. The potentials of these molecules in other formulations will be explored with exemplary formulations.
Evaluation of Some Adjuvants for Improving Glyphosate Efficacy
Authors: Singh S , Singh M
Published: April 2008

Glyphosate is the most common non-selective post-emergence herbicide used under diverse conditions. The efficacy of foliar applied herbicides is greatly influenced by adjuvants, but not all adjuvants have a synergistic effect. Greenhouse experiments were conducted using weed species of Echinochola crus-galli, Panicum maximum, Bidens pilosa, and Abutilon theophrasti to evaluate glyphosate efficacy by tank mixing with 0.5 % of Blaze®, Condition®, Improve®, and Induce®. Glyphosate at 0, 0.14, 0.28, and 0.56 kg ae/ha alone and with adjuvants was sprayed at the 4 leaf stage of weeds. Surface tension and contact angle were measured under lab conditions.

Adjuvants increased the activity of glyphosate by 15–29 % compared to glyphosate alone. Among the weed species, higher mortality was observed in P. maximum and B. pilosa followed by E. crus-galli and lowest in A. theophrasti. On mortality of grass and broadleaf weed species, significant differences were observed by tank mixing glyphosate with different adjuvants. Lowest Contact Angle (CA) and Surface Tension (ST) were recorded when glyphosate (Rodeo®, with no surfactant) was mixed with Improve and Blaze surfactants, which was significantly lower than glyphosate formulation pre-mixed with surfactant (Roundup UltraMax®). In the case of Condition, the relative decrease in CA was less than ST when added to glyphosate, compared to Improve and Blaze. Lower ST and CA of glyphosate tank mixed with Improve and Blaze correlated with improved weed mortality in the activity study.
Elemental Analysis of Lubricating Grease by Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES)
Authors: Fox BS
Published: April 2008

Lubricating grease is a mixture with complex properties that poses far more difficult nalytical challenges than do its individual components. At many petroleum testing laboratories, Inductively Coupled Plasma Atomic Emission Spectroscopy, or ICP-AES, is used for the analysis of additive elements and wear metals in oil. However, it may also be used to measure the concentration of both additive metals and contaminants in lubricating grease. However, unlike some of the other matrices that are routinely analyzed, grease cannot be simply diluted for direct sample introduction into the instrument without some form of acid digestion. This paper will discuss how ICP-AES is used as a grease analysis tool. Several sample preparation schemes will be covered, including classical sulfated ash on a hot plate, microwave assisted dry ash, and microwave assisted acid digestion. Comparison data from different digestion techniques will illustrate potential problems that may be encountered by the analyst in each of these methods. The advantages of closed-vessel microwave digestion for the analysis of elements that are often volatilized under normal digestion conditions will be discussed.
Latest Improvements on Using Polarized X-Ray Excitation EDXRF for the Analysis of Low Sulfur Content in Automotive Fuel
Authors: Wissmann D
Published: April 2008

Polarized X-Ray EDXRF has been used for the analysis of low levels of a broad range of elements in light matrices for a long time. By using the polarization of the excitation radiation, the background scattered by the sample is drastically reduced. For the analysis of low sulfur in automotive fuels, this meant a detection limit comparable to the WDXRF technique.

Recent developments in detector technology and in closed coupled static geometry result in further improvement of sensitivity for this application.

This paper shows the development of this technique for the analysis of low sulfur content in petroleum products. It shows the results of a round robin test, performed by CEN TC 19 WG 27 in 2001.

The technical basis of these data is compared to the recent technical developments, and future options are shown. The influence by sample preparation and sample presentation, which might be special for this analytical technique, is investigated and discussed.
Performance of Geosynthetic Clay Liners Used in Two Landfill Closures in a Coastal Area of Florida
Authors: Mackey RE , Olsta JT
Published: April 2008

Landfill caps may present GCLs with one of the most difficult environmental conditions in which to perform. The low confining pressure of the cover soil allows for greater separation of the sodium montmorillonite platelets. The GCL is more susceptible to ion exchange at these low confining pressures. Coastal areas of Florida have a greater potential for the presence of calcium within the sandy soil cover placed over the GCL to function as a drainage layer and protective cover. This combination of low confining pressure and the presence of calcium carbonate may increase the hydraulic conductivity of the GCL over time. This paper will detail an investigation of a 5 year old plus GCL barrier layer within two landfill closures for a coastal Florida county and determine if any changes in properties of the bentonite/GCLs have occurred. The samples were tested for hydraulic conductivity, fluid loss, swell index, and ion content. The samples were also inspected for root penetration. Samples of the soils placed above and below the GCL were also analyzed for ion content and bentonite compatibility.
How Fast Do Winter Sports Participants Travel on Alpine Slopes?
Authors: Shealy JE , Ettlinger CF , Johnson RJ
Published: April 2008

This study was developed to empirically determine the impact of the following variables on the speeds of skiers and snowboarders: activity [skiing versus snowboarding], visibility [clear and sunny sky versus cloudy, overcast conditions], type of resort [day, destination, or combination], and helmets [use or not of helmet]. The study also evaluated differences in speed between males and females and the ability of subjects to estimate their speed.

The authors measured the speed of some 650 individuals at three different ski resorts in the U.S. during the winter of 2002/2003. One resort was primarily a destination resort in Utah, one was a day area in New York, and the third resort in Vermont had a combination of destination and day skiers. The speeds were determined by means of a calibrated radar speed gun. Speeds were gathered on consecutive skiers and snowboarders as they were observed from an uphill, looking downhill position. The speed recorded was the highest speed observed during a several second interval while the observed person went through several turns as the skiers and snowboarders moved away from the observer. All observations were made on wide, straight, well-groomed ‘blue square’ (more difficult) trails. The slopes ranged from 16–20° in steepness.

The average speed for all observations was 43.0 km/h (26.7 mph), with a standard deviation of 11.2 km/h (7.0 mph). The average speed for skiers of 44.5 km/h (27.6 mph) was significantly higher than that for snowboarders at 38.9 km/h (24.1 mph). The average speed under good visibility of 46.7 km/h (29.0 mph) was significantly higher than for poor visibility conditions at 38.3 km/h (23.7 mph). The average speed for helmet users of 45.8 km/h (28.4 mph) was significantly higher than those not using a helmet at 41.0 km/h (25.4 mph). Males ski and snowboard significantly faster than females. Skiers and snowboarders are fair at estimating their speed (r = 0 56), but they tend to underestimate their speeds the faster they go; for example, at an actual 48 km/h (30 mph), they estimate that they are traveling at 37 km/h (23 mph).

The observed speeds are well above the speeds (22.6 km/h, or 14.0 mph) used for ASTM F 2040 helmet testing protocols for recreational snow sports helmets.
Comparison of Static and Dynamic Transition Temperature Shifts in VVR Reactor Pressure Vessel Steels
Authors: Brumovsky M , Falcnik M , Kytka M , Malek J , Novosad P
Published: April 2008

This paper summarizes results from surveillance specimen programs of VVER-440/V-213C type reactors. Transition temperature shifts, induced by irradiation, and determined from impact Charpy V-notch toughness as well as from static fracture toughness tests on pre-cracked Charpy size specimens, (COD) are compared. Two methods have been used for determination of static fracture toughness shifts — standard COD type specimens from standard surveillance programs and reconstituted COD type specimens from broken halves of Charpy V-notch specimens; thus identical irradiation conditions have been assured. Results obtained are discussed from the point of view of irradiation conditions as well as of different type of testing. Additional tests have been performed on different heats from WER-1000 type steel, where Charpy V-notch impact and static as well as dynamic fracture toughness tests have been performed to determine transition temperature shifts. Results are discussed and show that transition temperature shifts from static tests are, generally, larger than those from dynamic tests.
Bias and Precision of To Values Determined Using ASTM Standard E 1921-97 for Nuclear Reactor Pressure Vessel Steels
Authors: Kirk M , Lott R , Server WL , Hardies R , Rosinski S
Published: April 2008

Recently ASTM adopted a Test Method for the Determination of Reference Temperature, To, for Ferritic Steels in the Transition Range (E1921-97). This test method quantifies the variation of fracture toughness with temperature throughout the transition regime based on limited replicate testing at a single temperature. Advances in elastic plastic fracture mechanics enabled adoption of size requirements in E1921-97 that permit testing of specimens as small as 10 mm cross section. Thus, E1921-97 presents the first opportunity to measure directly the fracture toughness of samples removed from surveillance capsules, rather than inferring toughness using RTNDT indexed KIC curve.

We assemble a database of fracture toughness values for reactor pressure vessel steels, including over 1,600 E1921-97 valid fracture toughness values for both irradiated and unirradiated steels. In this paper, we use this database to address concerns regarding the bias and pecision of To values determined by ASTM E1921-97, and regarding the use of To as an index temperature for the ASME KIC curve. When the requirements of E1921-97 are satisfied, neither the temperature at which the fracture toughness tests are conducted nor the level of deformation prior to fracture bias the estimate of To. Furthermore, the recently proposed To-based index for the KIC curve (RTTo ≡ To+ 35°F) reduces considerably the degree of scatter in facture toughness data, and contains implicit margins on toughness that are consistent for every steel considered. RTTo is superior to RTNDT as an index temperature for the KIC curve, and also provides for a more conservative assessment of vessel safety than does RTNDT.