bluuebunny/crossref_metadata_2025 huggingface dataset:
Decontamination of Fluoropolymer Barrier-Based Chemical Protective Clothing
Authors: Sinofsky MW , Stull JO , Dodgen CR
Published: March 2009

A combined modelling and testing program was undertaken to quantify the effectiveness of a common field decontamination procedure used on protective clothing constructed of a fluoropolymer barrier-based material. Variables such as vapor pressure, water solubility, and the ability of the chemical to permeate the composite were used to select a battery of test chemicals. Sample material specimens were exposed to selected chemicals, washed with hot soapy water and allowed to aerate. Offgassing rates were measured during aeration and used in models developed to simulate different possible exposure scenarios which were then compared to industrial hygiene toxicity measures. After aeration, the samples were analyzed using solvent extraction and gas chromatography to identify residual contamination. Subsequent permeation tests were performed for a subset of the chemicals to determine possible changes in material chemical resistance following prior chemical exposure and decontamination. The results of this testing show that chemical offgassing from the material and residual chemical remaining in the material were below levels which could pose harm to suit wearers. The most important criteria in determining the safety associated with decontamination were found to be the chemical toxicity and the nature of the chemical contact.
Concurrent Engineering in the Design of Protective Clothing: Interfacing with Equipment Design
Authors: Ashdown SP , Watkins SM
Published: March 2009

Most protective clothing is designed for use with existing equipment. Sometimes for economic reasons or because of immediate needs, design of protective apparel and associated equipment must take place simultaneously. An example of such a project is described, and a model for a concurrent design process proposed. The project consisted of development of a totally encapsulating chemical protective suit. Suit design was carried out concurrently with design of air supply systems and microclimatic conditioning equipment. Two factors that made this project possible were a system of centralized communication that maintained contact between the various designers, and the implementation of a zone approach to the design of the suit. Each zone was independently supported on the body using a system of bands, straps, and tethers. This allowed design development using a series of partial prototypes of different zones, each appropriate to the current level of development of the associated equipment and each operating relatively independently of the whole. Design work on the suit could therefore continue at the same time as design work on other equipment.
Implementation of the New ASTM F1461 Practice for a Chemical Protective Program
Authors: Mansdorf SZ
Published: March 2009

The ASTM Committee F23.7 on use has written a new standard practice for the development and implementation of a management program for the selection, use and maintenance of clothing to provide protection against potentially hazardous chemicals. The practice lists 11 minimum program requirements including the requirement for a written program document. At this time, there are no specific regulatory requirements for a written program document for the selection and use of chemical protective clothing. Nevertheless, it is clear that a written management plan would be beneficial. The ASTM standard practice represents a consensus program document that should serve as a model for organizations interested in reducing the risk of worker injuries and illness from dermal hazards.
Developing and Applying a Material Specification for NASA's Propellant Handlers Ensemble
Authors: Stull JO , Thompson KG , Vahdat N
Published: March 2009

An evaluation program was undertaken to choose new materials for NASA's propellant handlers' ensemble (PHE) used in the operations involving the transfer of hypergolic fuels and other hazardous chemicals. NASA currently uses an encapsulating suit constructed of a chlorobutyl rubber/Nomex® material in conjunction with a liquid air self-contained breathing apparatus (SCBA). The inventory of 300 suits and SCBAs are subjected to approximately 8000 wearings per year, and require an extensive maintenance and recycling program to ensure their continued effectiveness.

A review of existing NASA suit requirements and applications indicated a number of parameters important in the selection of the suit materials and seam construction. Other ensemble clothing items such as visors, gloves, boots, and suit closure systems were also considered. Performance criteria were developed based on existing NASA specifications and requirements in the National Fire Protection Association standard on vapor-protective suits (NFPA 1991). A life cycle cost analysis of the suits provided the range of material/suit costs based on expected service life. This information was used to develop a new specification that was submitted to industry for soliciting material candidates.

Baseline performance data were generated for the existing chlorobutyl rubber/Nomex material and related suit materials. A rating system was developed to assist selection and testing of replacement materials.
European and International Standards for Protective Clothing and Their Influence on Manufacturing, Trade and Use
Authors: Zimmerli T
Published: March 2009

Standards on protective clothing have been worked on in ISO for over twenty years. For the common market in Europe the different national regulations and standards had to be harmonized in order to eliminate all non tariff trade barriers between the different countries. So CEN started only a few years ago to develop standards for protective clothing. The manufacturing and the use of protective clothing and all other types of PPE is laid down in several EC directives. Products which fulfil the essential requirements of these directives get the CE mark and can be freely moved and sold in the whole common market. Now an effort is made to harmonize the CEN with the ISO standards. This would help not only the free exchange of goods inside the European market but also throughout the whole world.
A Sensitivity Study of a Variable-Property Skin Burn Model Considering the Variability of Water Content
Authors: Halin J , Mulligan J , Hamouda H , Barker R , Soroka A
Published: March 2009

A skin burn model using variable thermophysical properties as a function of water content is studied as it is subjected to a heat flux at the skin surface. The model employs the finite element method to solve Pennes' [1] bio-heat equation as it is subjected to heat fluxes modeled from actual sensor test data. The model assesses burn damage using the burn integral of Henriques [2] using burn-threshold criteria Ω at both the epidermal-dermal and dermal-subcutaneous tissue interface. The model's times-to-degree burn, cumulative burn damage Ω, and peak temperatures are studied as the blood perfusion rate and water contents for the respective layers of skin are separately and arbitrarily varied. Results from the variable- and constant-property Pennes' models are compared.
Morphology and pH Changes in Leached Solidified/Stabilized Waste Forms
Authors: Cheng KY , Bishop PL
Published: March 2009

Leaching of cement-based waste forms in acetic acid solutions with different acidic strengths has been investigated in this work. The examination of the morphology and pH profile along the acid penetration route by an optical microscope and various pH color indicators is reported. A clear-cut leaching boundary, where the pH changes from below 6 in the leached surface layers to above 12 in the unleached waste form, was observed in every leached sample.
Chemical Characterization of Pore Water of a Solidified Hazardous Waste
Authors: Trussell S , Batchelor B
Published: March 2009

Immoblilization of four heavy metals by solidification/stabilization with portland cement was studied over a range of total metal concentrations and water/cement ratios. Pore water concentrations of each metal were measured to provide information about the degree of immobilization at presumed metastable equilibrium conditions in the synthetic wasteform and about possible immobilization mechanisms. Leaching behavior of crushed samples over a wide pH range also provided information about leach resistance and possible binding mechanisms.
Influence of Silica Fume on the Immobilization Properties of Cementitious Mortars Exposed to Freeze-Thaw Cycles
Authors: Quaresima R , Scoccia G , Volpe R , Medici F , Merli C
Published: March 2009

This study deals with the durability of immobilization matrices, drawing comparisons among the release characteristics of cementitious mortars with or without silica fume, before and after freezing-thawing cycles. Three different dosages of silica fume have been experimented, using silica fume as a substitute of cement. The results obtained from the leaching tests have emphasized, in all the matrices which had undergone the freeze-thaw cycles, an increase of the percentage of tracer released with respect to the same matrices before the freezing-thawing cycles. As a consequence of the freezing-thawing cycles, the velocity of release has also increased in all the experimented matrices. However, the tests have reconfirmed the positive effect of the addition of silica fume.
Stabilization of Heavy Metals in Portland Cement Matrix: Effects on Paste Properties
Authors: Bhatty JI , West PB
Published: March 2009

Effects of heavy metals on the physical and chemical properties of cement pastes were studied using different types of cement, four metal oxides and four soluble metal salts. Type I (high aluminate content) and Type V (low aluminate content) cements were used to study the effects of their chemical differences on paste properties and metal stabilization. Fresh pastes were tested for workability, initial setting times, and heats of hydration. Hardened pastes were tested for strength and leachability by both TCLP and column leaching with acetic acid.

Initial setting times for pastes were significantly retarded by cadmium oxide and either form of lead and flow also decreased. Effects on setting time, slump area, and increased conduction calorimetry induction times are more pronounced with higher levels of lead and cadmium oxide. Addition of soluble chromium(III) chloride caused accelerated setting, higher paste temperatures, and smaller slump areas with both types of cement. In general Type V cement pastes with either soluble salts or oxides exhibit longer setting and induction times, and larger slump areas compared to Type I pastes.

Slow setting pastes had low three day strengths while fast setting pastes had high strengths at this age. However, the ninety day strengths of cement pastes is near control strengths for both Type I and Type V cements.

Leaching results were similar to those found by other workers. In these very cement-rich solids, chromium and cadmium were well stabilized but higher lead and mercury leaching was observed.
Evaluation of Alternative Drilling Technologies and Subsurface Confinement Barriers for Single Shell Tanks at Hanford
Authors: Acheson WP , Towers TA , Wentzel KW , Johnson HR , Overbey WK
Published: March 2009

Many of the single-shell tanks at Hanford are well beyond design life and are perceived as being in imminent danger of failure. Some of the tanks have already failed. Over the years, tank leaks and spills have contaminated the soils; the soil contamination raises issues about the characterization of the tanks, closure of the tanks, and the safety of the tank farms. This study investigated the application of conventional and innovative drilling techniques to the problems of soil characterization, monitoring, and barrier installation (both desiccant and physical/grout types) beneath the Hanford C tank farm.

An evaluation and ranking of twenty four types of drilling technologies included horizontal and directional drilling techniques developed by the oil and gas industry, the mining and minerals extraction industry, and others. The drilling technologies were evaluated for their ability to drill in unconsolidated soils, provide good horizontal and vertical position control, facilitate subsurface characterization and monitoring, and permit installation of subsurface barriers beneath individual tanks or beneath a tank farm. Barrier placement and soil stabilization for remediation applications presents many challenges, particularly at the Hanford Site.

For example, one facet of the study included investigation and concept development of barrier systems which could be installed beneath and around the tank farms with a minimum of excavation. The barrier concepts--existing, commercially available technologies--had to be suitable for the variety of soil conditions found beneath the Hanford tank farms. The barriers were also investigated for their ability to withstand chemical attack and seismic deformations, and for their ability to have the barrier integrity verified remotely.

The best barrier technologies and drilling systems were combined into seven integrated barrier systems which were evaluated and ranked for their suitability to the Hanford site, their ability to meet environmental constraints, the safety of personnel working on the site, and the ability of the barrier to withstand large and small tank leaks. Each of these seven systems were then evaluated in terms of relative amounts of material extracted, deployment time, and costs.

The two highest ranked barrier systems developed were a circulating air barrier and a cone grouting barrier. Both are candidates for quick deployment and application to single or multiple tank systems. Both systems are candidates for demonstration at a cold test at the Hanford site. Two other potentially applicable barrier systems were evaluated, permeation grouting from horizontal wells and fracture grouting. Both are candidates for continued development and demonstration.
Remediation of Lead-Contaminated Soils at Small Arms Ranges
Authors: Gavaskar AR , Means JL , Heath JC , Nelson B
Published: March 2009

The objectives of this study were to assess the level of lead contamination at the U.S. Navy's small arms ranges, to determine the potential for non-point source pollution, and to select and apply a remediation technology suitable to such sites. A combination of screening and stabilization were selected as the best remedy following bench-scale and field-pilot testing. Binders tested at bench scale included cement, cement-silicate, and lime-fly ash. Optimum treatment was achieved with either cement or a combination of cement and silicate.
Sulfur Polymer Cement, a Final Waste form for Radioactive and Hazardous Wastes
Authors: Darnell GR
Published: March 2009

Because of its unusual properties, sulfur polymer cement (SPC) is a promising solidification and stabilization agent for radioactive and hazardous wastes. SPC accepts no water and requires no activation agents. It always melts at 115°C and pours at 135°C; therefore, economical remediation is offered through remelt and addition of additives or more SPC to meet specifications. Compressive strength upon cooling is approximately 27.6 MPa (4 000 psi). SPC has survived for years in acids and salts that destroy or severely damage hydraulic concretes in months or even weeks. In tests with 5 wt% loading of pure toxic metal oxides in powder form, the U.S. Environmental Protection Agency's the toxicity characteristic leaching procedure shows the maximum leachate concentration of mercury, lead, silver, arsenic, barium, and chromium to be less than their established threshold limits. Tests to determine SPC's expected longevity are being conducted and are encouraging.
Lab-Scale Tests on ISV Vapor Transport Phenomena
Authors: Farnsworth RK , Gardner BM
Published: March 2009

In situ vitrification (ISV) is a promising technology for remediating buried waste sites and contaminated soil sites. However, concerns exist that low soil permeabilities may limit vapor transport away from the advancing melt front and cause a melt expulsion that breaches ISV containment. As a result, two ISV lab tests were conducted at the Idaho National Engineering Laboratory (INEL) using INEL soil (permeability: 10-6 cm/s) and a low permeability (10-10 cm/s) clay material. The clay test also had a ceramic tube inserted vertically through the center of the area being melted to provide one-dimensional data on vapor transport. Results confirm that low soil permeabilities can limit vapor transport away from the advancing ISV melt front. In addition, peak pressures inside the ceramic tube were significantly greater than those outside the tube, indicating the importance of horizontal vapor transport around the advancing ISV melt front.
Summary of Technical Resource Document on Solidification/Stabilization and Its Application to Waste Materials
Authors: Means JL , Smith LA , Nehring KW , Brauning SE , Mashni CI , Wiles CC
Published: March 2009

The Technical Resource Document on Solidification/Stabilization and Its Application to Waste Materials (TRD) is a technical resource for the S/S user community and a guide to promote the best future applications of S/S processes. A potential hurdle for any S/S project is the fact that although the standard bulk materials handling and mixing equipment processes used in S/S processes make the technology appear simple, there are significant technical challenges to the successful application of S/S processes. In order to help users meet such challenges, the TRD describes technology screening procedures and summarizes the status of S/S processes to assist users and reviewers in their selection, planning, and application of S/S technology.
Abrasive Blast Material Utilization in Asphalt Roadbed Material
Authors: Means JL , Nehring KW , Heath JC
Published: March 2009

The State of California has promulgated rules on “California-only” hazardous wastes that offer the potential for some of these wastes to be recycled or reused. Abrasive blast material (ABM) from military and commercial operations such as sandblasting may fall into the category of waste that can be reused. Experiments were conducted on spent sandblasting grit to determine whether the grit could be incorporated into asphalt concrete for use as roadbed material, and a test roadbed was laid to evaluate the long-term stability of the metals found in the grit. Incorporation of the ABM in asphalt helps reduce the mobility of metal contaminants making the material suitable for reuse. The results of the initial characterization, treatability testing, and follow-up measurements of core samples taken from the test roadbed are presented to show that the use of abrasive blast material in asphalt roadbed material is a viable option under the proposed California regulatory standards.
In-Situ Slurry Wall Formation with the SoilSawࡊ Barrier System
Authors: Carter EE
Published: March 2009

This new technology was designed to form high-quality “formed-in-place” barrier walls in soil in a more continuous and uniform manner than the two-step, excavate and replace, processes of conventional slurry trenching. Soils in the path of the device are pulverized in-situ and liquified by high-energy jets of a permeability modifying grout. The hardware then passes through the liquified soil under the pull of gravity. The soil/grout mixture hardens to form a plastic diaphragm wall. Walls can be formed from a variety of materials.

The bulk of the energy to cut and mix the soil is transferred to the soil work face hydraulicly by the slurry media itself. Massive energy transfer of over 2000 hydraulic horsepower (1500 kilowatts) supplied by oil field cement slurry pumps allows dramatic productivity rates. The production rate of the process is significantly reduced in highly cohesive soils. This paper presents an introductory look at a potentially useful new method of construction of large subsurface barriers and contrasts it with conventional methods.
Changing Agricultural Practices and the Future of Pesticides and Adjuvants
Authors: Dexter AG
Published: March 2009

Crops that have been genetically modified for pest control through biotechnology techniques (bioengineered) were planted on approximately 16 million U.S. acres in 1997. Corn and cotton that produce a toxic protein for insect control, the B.t. toxin, were planted on 5.1 million acres. Soybean resistant to glyphosate (Roundup Ultra®) was planted on 9 million acres. In total, corn was planted on 80.2 million acres, cotton on 14.0 million acres and soybean on 70.9 million acres in 1997 in the U.S. Counting multiple treatment as multiple acres, insecticides were applied annually to 31.5 million-acres of corn and 39.5 million acres of cotton. Herbicides were applied annually to 173.7 million acres of corn, 34.9 million acres of cotton and 147.7 million acres of soybean. After seed becomes fully available, B.t. corn is predicted to be seeded on 40% of the acres and B.t. cotton on 75% of the acres. This usage of B.t. corn and cotton would result in an estimated 21.3 million fewer acres treated with insecticide annually. After seed becomes fully available, varieties bioengineered for herbicide resistance will be seeded on a predicted 47% of the corn acreage, 50% of the cotton acreage and 80% of the soybean acreage. This usage of bioengineered herbicide resistant varieties would result in changes of herbicide practices on 217.2 million acres annually. Several soybean herbicides are often used with adjuvants. Glyphosate and glufosinate usually are applied without an added adjuvant. Usage of glyphosate or glufosinate on 75% of the soybean acreage would result in 58.5 million fewer acres treated with added adjuvant annually in soybean. Bioengineered crops will have the greatest impact on corn, cotton and soybean in the U.S. but bioengineering has potential applications in all crops.
Direct Chemical Injection and Small Volume Returnable Container Technology
Authors: Swenson OR , Manthey FA
Published: March 2009

Direct chemical injection and small volume returnable container (SVR) technology aid in minimizing worker exposure to concentrated pesticides. SVR containers allow the applicator to return unused pesticide to the dealer. This reduces the long-term on farm storage of pesticides and allows recycling of unused pesticide by the dealer. SVR containers also eliminate the problem of disposal of unneeded pesticides and pesticide containers by the applicator. Chemical injection systems directly meter concentrated pesticide into the water lines of the field sprayer. Connecting SVR containers to a direct injection system eliminates spray tank contamination and greatly reduces pesticide rinsate volume and environmental and worker exposure. Direct injection systems presently on the market are better suited for liquid than dry products, because of agitation and settling problems associated with dry formulations.
Effects of Flow Rate and Rotational Speed on Performance of Two Rotary Atomizers
Authors: Salyani M
Published: March 2009

A spray patternator was used to evaluate distribution patterns of the “Air-cone” and “Micromax” rotary atomizers. The atomizers were operated at combinations of three rotational speeds and three flow rates. Distribution patterns were obtained by recording the amount of collected water in the graduated cylinders. The Coefficient of Variation (CV) of the collected volumes was used as a criterion to evaluate the uniformity of the distribution patterns. Samples of the droplets were captured between two silicon oil layers and estimates of the droplet sizes were obtained by microscopy.

Both atomizers produced saddle-shaped patterns. The two halves of the patterns were different and flow rate and rotational speed affected their shapes. Droplet size decreased as flow rate decreased or speed increased.
Qualitative Properties of Spray Deposits — Patterns and Statistics
Authors: Downer RA , Taylor RAJ , Ebert TA , Thompson RS , Hall FR
Published: March 2009

Pesticides must be applied to the target area uniformly. Uniformity of sprayer output is typically described by the coefficient of variation (CV) of the spray emitted. However, deposit size, number, and concentration interactions are overlooked when using this statistic. A measurement technique and alternative statistics, capable of documenting and separating qualitatively different spray patterns produced by quantitatively similar spray distributions were evaluated. Water and Roundup® Ultra with and without Kinetic™ and AgRhô™ DR 2000 were applied to plastic tape at 93.5 L/ha through XR8O03VS, TT11003VP, and TDVC-03/06 tips. Nigrosin was used as a tracer. Deposits were allowed to dry and were photographed at 2 cm intervals across the swath using an image analysis system. Deposit structure (#/cm2, size distribution and applied volume) was analyzed for each subsample. The data showed that while differences could be shown to occur in individual parameters, better separation of treatments was achieved with the use of the diversity statistics.
Spray Retention is Affected by Spray Parameters, Species, and Adjuvants
Authors: Bruns DE , Nalewaja JD
Published: March 2009

Spray retained by soybean, [Glycine max (L.) Merr. var. Ozzie], common lambsquarters [Chenopodium album (L.)], and redroot pigweed [Amaranthus retroflexus (L.)] was determined using a dye spectrophotometric method for water sprays (without pesticides) varying volume, droplet size, and adjuvants. Spray retained based on leaf area generally was greater for small than large droplets and more for surfactants than for oil adjuvants. Surfactants, Tergitol® 15-S-9 and Tergitol® 15-S-30, enhanced spray retained more for common lambsquarters than redroot pigweed or soybean. The oil adjuvants, methylated canola oil (MCO), canola oil (CO), and petroleum oil (PO) generally reduced spray retained by redroot pigweed, but generally increased spray retained by common lambsquarters compared to water spray alone. Spray retained by soybean was also increased by oil adjuvants, except for PO applied in droplets from an 8004 nozzle. Spray retained decreased as spray volume increased from 160 to 320 L/ha for surfactants and 80 to 160 L/ha for CO and MCO. Species retained more spray as oil adjuvant concentration increased from 0.25 to 4% v/v. However, retention decreased when Tergitol® 15-S-9 and 15-S-30 increased from 1 to 4%. The results of the present research with a water carrier demonstrate that optimization of spray retention requires a consideration of adjuvants, species, and spray parameters.
Pesticide Stability Versus Clay Carrier Surface Acidity
Authors: Taylor DR , Stein J , Svidovsky N
Published: March 2009

Clay granules are well known as carriers for a broad range of pesticides including various insecticides, herbicides and fungicides. Although they generally function quite well in this applications, formulations utilizing chemically sensitive pesticides must often be augmented with organic deactivators such as dipropylene glycol, polypropylene glycol, etc. in order to stabilize the system against degradation of the active ingredient. The present paper reports on the use of clay carriers which have been processed in a new way that significantly enhances their chemical inertness by modifying surface activity (i.e.surface acidity). This objective has been realized without compromising hardness or liquid holding capacity. Utilizing these materials, we have attempted to draw a correlation between pesticide stability (measured as pKa value of first hydrolysis decomposition products) and carrier surface acidity. A number of well-known pesticide molecules chosen from the phosphate ester and thiocarbamate classes have been used to illustrate these correlations.
Formulation and Delivery Systems for Enhanced and Extended Activity of Biopesticides
Authors: Devisetty BN , Wang Y , Sudershan P , Kirkpatrick BL , Cibulsky RJ , Birkhold D
Published: March 2009

Biopesticides are formulated microorganisms such as bacteria, fungi, viruses, or more complex organisms such as protozoa and nematodes. While several commercial products based on microorganisms have been developed and registered under the Environmental Protection Agency (EPA), actual use of these biocontrol agents for protection of crops against insects, weeds, and plant pathogens has been limited and accounts for less than 2% of total pesticide use today. Factors contributing to this low usage include costly and inefficient production methods (especially for fungi and viruses), poor storage stability, and susceptibility to environmental degradation. These are caused by exposure to temperature and pH extremes, desiccation, moisture, proteolytic enzyme activity from both plants and resident microbes, and ultraviolet (UV) radiation. Other factors contributing to the limited usage of biopesticides are: susceptibility only at specific development stage of target pest or weed, slow action for infectivity and mortality, requirement for specific environmental conditions for efficacy, and need for thorough spray coverage. Despite these limitations, industry is commited to the development of biopesticides as environmentally friendly alternatives to synthetic chemicals. This may be the result of public concern and demand to significantly reduce or even eliminate the pesticide residues in the food chain, rapid and excessive development of pest and disease resistance to chemicals, and high costs associated with the development and registration of a new chemical active ingredient.

Significant progress in formulation and application method has been made to protect the biopesticides from environmental degradation. These developments include: non-aqueous formulations, incorporation of UV protectants, starch and sodium alginate encapsulation, and adjuvants for wash-off resistance, humectancy, increased infectivity, and enhanced activity. In addition, genetic engineering technologies, such as bioencapsulation and transgenic plants have been designed to protect and extend the activity of Bacillus thuringiensis. This paper will review the work done in the area of formulations and delivery systems to enhance and extend activity of biopesticides. Primary emphasis will be on Bacillus thuringiensis, which represents more than 90% of today's biopesticide market for agronomic crops, forestry, and aquatic pest control.
Physico-Chemical Properties of Several Commercial Organosilicones, Their Blends, and Selected Other Adjuvants
Authors: Sun J , Foy CL
Published: March 2009

The study was conducted to investigate the physico-chemical properties and the spread pattern on velvetleaf (Abutilon theophrasti Medikus) foliage of several organosilicones, oil concentrates, nonionic adjuvants, and adjuvant mixtures. A dynamic contact angle analyzer, surface tensiometer, and goniometer were used to measure the static surface tension, dynamic surface tension, and contact angle, respectively, of solutions made with these adjuvants. The progress of droplet spread of different adjuvant solutions containing fluorescent dye on leaves of velvetleaf was recorded by image analyzer. Organosilicones were superior wetting agents and showed excellent spreading patterns on velvetleaf foliage. In addition, organosilicones not only exhibited extremely low static surface tension, but also showed superior performance in lowering dynamic surface tension. A logistic dose response relationship existed between adjuvant concentration and contact angle on parafilm. However, across a wide range of concentrations, there was no clear relationship between surface tension and contact angle even in a homogeneous adjuvant solution; although, at normal use rates, the lower the surface tension, the lower the contact angle should be on target surfaces.
Fluorescence as a Tool for Optimizing Adjuvants with a Photosynthesis-Inhibiting Herbicide
Authors: de Ruiter H , Uffing AJM , Meinen E
Published: March 2009

The first objective of the study was to investigate whether measurement of leaf fluorescence can predict the inhibition of plant growth by the herbicide metoxuron. The second objective was to investigate whether fluorescence can be used as a tool for optimizing adjuvants for metoxuron. Metoxuron inhibits photosynthesis and as a consequence increases leaf fluorescence. Fluorescence was used to monitor metoxuron activity shortly after foliar application to common lambsquarters (Chenopodium album L.), black nightshade (Solatium nigrum L), and pea (Pisum sativum L.).

Varying the dose of commercially formulated metoxuron (wettable powder) demonstrated that fluorescence, measured 3 h (for common lambsquarters and pea) or 24 h (all species) after treatment, correlated well with the reduction of fresh weight determined 8 to 14 days after treatment. In order to optimize an emulsifiable rapeseed oil for metoxuron, we varied the concentration of emulsifier (polyoxyethylene C13/C15 oxo alcohol) in the oil (2.5, 10, and 40% w/v) and the concentration of emulsifiable oil in the spray solution (0.001, 0.01, 0.1, and 1% v/v). Generally, the concentration of the oil adjuvant in the spray solution was much more relevant to metoxuron activity than the emulsifier content of the oil. In common lambsquarters and in black nightshade the lowest concentration of oil tested (0.001%) was effective. In pea, the oil was effective at 0.01% and above. The fluorescence measurements with the metoxuron-adjuvant combinations correlated well with the influence of these combinations on the reduction of fresh weight of the species.

We conclude that fluorescence can be a rapid, accurate, and time-saving tool for the comparison of adjuvants or formulations for photosynthesis-inhibiting herbicides.
A Comparison of Principles in Several Architectual Conservation Standards
Authors: Bronski MB , Gabby BA
Published: March 2009

Numerous architectural conservation standards, charters, guidelines, and other documents exist that provide guidance and consistency to practitioners in determining appropriate and sensitive treatments for historic buildings. This paper compares the conservation principles stated in six well-known standards.
Weathering and the Performance Equation: Moving Towards Visual Standards
Authors: Atkinson B
Published: March 2009

Performance codes are now in use internationally after a twenty-year eriod of gestation. The performance equation and its philosophy is introduced and its relationship with the current performance concepts described. Its original use as a generic framework for research into the performance of the external fabric is outlined.

Standards lend themselves readily to numerically defined phenomena. The ubjective nature of some weathering causal factors and the difficulties of measuring these are highlighted. The decision to restore the appearance of architectural buildings falls into this category of preservation. Visual changes lack definitive descriptors, but the paper reviews those available causal factors that would be useful in modeling the phenomena. Each major descriptor such as precipitation and pollution, and their components are considered in turn. Recognized patterns of surface soiling are presented.

It is held that Preservation standards related to changes in appearance begin with studies of rainfall and particulate distributions over buildings. Measures of aesthetic or visual failure are required because these processes have to eventually form a valid part of a preservation philosophy; and need to be covered by performance codes. By their longevity and example, historic buildings provide a laboratory of case studies. The paper suggests that standardization of visual change will involve standardization of interactive modeling techniques rather than direct testing.
Compatibility and Retreatability Versus Reversibility: A Case Study at the Late Hellenistic Nymphaeum of Sagalassos (Turkey)
Authors: VanBalen KEP , Ercan S , Patricio TC
Published: March 2009

Anastylosis has been used as the conservation method for the late-Hellenistic Nymphaeum at the archaeological site of Sagalassos (Turkey, Prov. of BURDUR). The original fragments of the U-shaped fountain building have been excavated, and restored, with missing parts completed as a step towards reassembling all of the building fragments necessary to restore the structure. Materials and techniques used for the gluing and completing of the different stone fragments have been chosen based on the general principle of retreatability leaving aside the generally accepted use of ductile materials for reinforcement. This choice has been made despite the fact that in structural engineering ductility is often used as an additional safety domain. The technique of reinforcement and reconnecting fragments was based on the use of epoxy binder and fiberglass bars. This solution creates a brittle behavior at ultimate strength of those structural components which is less than the strength of the stone and therefore guarantees possible retreatability.

The results of preliminary tests, the application at the site on the building and the final result of the Anastylosis are presented.
The Problems of Assessing Historic Timber Strengths Using Modern Design Codes
Authors: Yeomans DT
Published: March 2009

Engineers dealing with historic structures frequently have to adapt standards created for those designing new structures. In Britain the timber design code was changed in 1984 in such a way that the behavior of historic buildings has, since then, to be justified in terms of an obsolete code of practice, especially when dealing with oak, which was removed from the recognized species. Although there has recently been a modification of the new code to reinstate oak, the material used in a group of significant historic buildings, the position is still far from satisfactory. This paper outlines the changes in the code and offers some pointers towards the form that a code for historic timber structure might take in Britain.
Rilem TC Characterization of Old Mortars with Respect to their Repair
Authors: Thomson M , Groot C
Published: March 2009

RILEM TC Characterization of old mortars with respect to their repair was established in the fall of 1996. Its objectives are for the establishment of general performance criteria and recommendations dealing with mortars for restoring and repairing existing masonry. The deliverables of the committee will take into account: 1. Characterization of old mortars in order to reproduce similar mortars for restoration and repair; 2. Identification of fundamental parameters and standardization of testing methods for measuring them.
An Instrumented Geogrid Reinforced Slope in Central Italy: Field Measurements and FEM Analysis Results
Authors: Montanelli F , Recalcati P , Rimoldi P
Published: March 2009

A 15 m high green faced reinforced slope was built in 1996 to stabilise a landslide situated on the Montone hill in the province of Perugia (Italy). The reinforced slope was built using locally available soils as fill material and HDPE mono-oriented extruded geogrids as reinforcement. The reinforced slope has been instrumented with strain gages connected to the reinforcing geogrids and with total pressure cells; full scale in situ pull-out tests have been performed as well.

The preliminary results demonstrate the good performance of the geogrids and define possible failure mechanisms for slopes with stepped geometry. The in situ pull-out test results validate laboratory tests performed in the past. To evaluate the field stress and deformation behavior of the reinforced slope a finite element analysis has been carried out. The paper describes the model technique developed to evaluate the field stress and deformation of steep reinforced slope using special interface elements. The results of finite element analysis are in agreement with the field measured results.
Instrumentation and Long Term Monitoring of a Soil Nailed Slope at Madeira Walk, Exmouth, UK
Authors: Barley AD , Davies MCR , Jones AM
Published: March 2009

This paper describes the field instrumentation of a soil nailed slope undertaken at Madeira Walk, Exmouth, UK. The instrumentation consists of strain gauged steel bars that are employed as soil nails to maintain stability of a slope. The nature of the stabilisation works and the instrumentation used to monitor the axial load induced in the soil nails are described. Initial results are presented showing the changes in axial load induced in the nails.
Instrumentation for Slope Stability - Experience from an Urban Area
Authors: Flentje P , Chowdhury RN
Published: March 2009

This paper describes the monitoring of several existing landslides in an urban area near Wollongong in the state of New South Wales, Australia. A brief overview of topography and geology is given and reference is made to the types of slope movement, processes and causal factors. Often the slope movements are extremely slow and imperceptible to the eye, and catastrophic failures are quite infrequent. However, cumulative movements at these slower rates do, over time, cause considerable distress to structures and disrupt residential areas and transport routes. Inclinometers and piezometers have been installed at a number of locations and monitoring of these has been very useful. The performance of instrumentation at different sites is discussed in relation to the monitoring of slope movements and pore pressures. Interval rates of inclinometer shear displacement have been compared with various periods of cumulative rainfall to assess the relationships.
Documentation of Data Collected from Field Instrumentation for Spatial Applications
Authors: Hansen DT
Published: March 2009

Data from field instruments are increasingly being incorporated into Geographic Information Systems (GIS). This adds a geospatial component to time series data and permits analysis and display with other geospatial data. From the perspective of GIS analysis, two issues are of importance. The first is the identification and description of the instrument location. The second is the description of the data stream from the sensor package and the access to that data for analysis and display. They are the basis for effective and proper use of the data from the instrumented site.

The spatial location of the sensor or sensor array in latitude and longitude or in a map projection system is a critical parameter for the use of the data in GIS. The accuracy of the spatial locations of sensors is important in identifying the spatial analysis that is appropriate for the data. Besides geographic coordinate information, local coordinate information available for the site is valuable information for locating the sites and instruments. Local coordinate information often is more accurately known than the geographic position. Local coordinate information can be used in computer modeling of the sensor data independently and can be used to refine the initial values of geographic coordinates.

To effectively use data captured from the instruments, information on the structure and contents of the data base is required. Sensor data may then be carried into the GIS data base management system (DBMS) or accessed from the DBMS set up for the time series data. For effective use and application of the data, all require information on the parameters being captured. For GIS data, this information is described as elements in ASTM D 5714-95 Content Specifications for Geospatial Metadata.
Review of GIS Developments in Geotechnical Instrumentation on the Central Artery/Tunnel Project, Boston, Massachusetts
Authors: Bobrow DJ , Vaghar S
Published: March 2009

This paper discusses the Geographic Information System (GIS) application which has been developed for rapid analyses and reporting of instrumentation and survey data on the Central Artery/Tunnel Project, in Boston, Massachusetts. Recent developments of the GIS application have included the addition of modules for preparing groundwater and settlement contour plans, and integration of digital photographs into the projectwide mapping. A module for inserting geological cross sections is underway.
The Crack Tip Displacement Vector Approach to Mixed-Mode Fracture
Authors: Dalle Donne C
Published: March 2009

A method for assessing the ductile failure of thin structures containing arbitrarily oriented cracks is presented. The crack tip displacement vector δv is used as fracture parameter. Experiments carried out on 4- to 6-mm-thick steel StE 550 and aluminum alloy A12024-T3 sheets with various mixed-mode specimens demonstrate that δv is more appropriate to characterize ductile mixed Mode I/II crack initiation and stable crack growth than the J-integral. The Mode I crack resistance curves of standardized C(T)-type specimens give a conservative estimate of crack initiation and resistance to stable growth in the range of near Mode II loading to pure Mode I loading. The δv>-parameter of a cracked component is evaluated with Engineering Treatment Model (ETM). The analytical ETM method requires only the stress intensity factor and plastic limit load solutions of the considered structure as well as the material stress and strain power law as input parameters. Close agreement of ETM predictions to the experimental load versus δv relationships or load-displacement curves can be achieved, if the proper limit load solution of the cracked structure is available.
A Simple Theory for Describing the Transition Between Tensile and Shear Mechanisms in Mode I, II, III, and Mixed-Mode Fracture
Authors: Chao Y-J , Zhu X-K
Published: March 2009

Fracture of solids containing a crack is interpreted using basic material data such as the fracture stress in tension, σC, and the fracture stress in shear, τC, both being determined from simple laboratory tests. Mode I, II, III, and mixed-mode I/II cases are analyzed individually to confirm the proposed theory. It is shown that the transition of fracture mechanism from tensile to shear, as observed for ductile materials but not observed for brittle materials in many fracture tests, can be properly explained and predicted by incorporating a material strength ratio defined as τC/σC.
Mixed-Mode Fracture Mechanics Parameters of Elliptical Interface Cracks in Anisotropic Bimaterials
Authors: Xue Y , Qu J
Published: March 2009

Two-dimensional interface cracks in anisotropic bimaterials have been studied extensively in the literature. However, solutions to three-dimensional interface cracks in anisotropic bimaterials are not available, except for circular (penny-shaped) cracks. In this paper, an elliptical crack on the interface between two anisotropic elastic half-spaces is considered. A formal solution is obtained by using the Stroh method in two dimensional elasticity in conjunction with the Fourier transform method. To illustrate the solution procedure, an elliptical delamination in a cross-ply composite is solved. Numerical results of the stress intensity factors and energy release rate along the crack front are obtained terms of the interfacial matrix M. It is found that the fields near the crack front are often in mixed mode, due to material anisotropy and the three dimensional nature of the crack front.