bluuebunny/crossref_metadata_2025_split huggingface dataset:
Centrifuge Modeling of In situ Surfactant Enhanced Flushing of Diesel Contaminated Soil
Authors: Pasha Amin Yousefnia , Hu Liming , Meegoda Jay N. , Aflaki Esmail , Du Jianting 
Published: July 2011

Abstract
In this research the effectiveness of physical modeling of in situ flushing with water and a surfactant solution was evaluated using a geotechnical centrifuge. The centrifugal experiments consist of two parts: transport of diesel through fine grain soils and remediation of diesel contaminated soil. First, 7.74 m3 of diesel per meter (width) was infiltrated into a 15 m thick prototype layer of fine grain unsaturated soil. Then contaminated soil was remediated by continuous flushing with two liquids (water and 1% (wt/v) aqueous solution of sodium dodecyl sulfate (SDS) surfactant) while subjecting the sample to 50 g acceleration. Effectiveness of soil remediation by flushing with 1% (wt/v) SDS surfactant was investigated in this research and compared that to flushing with water without additives. The total volume of injected remediation solution over 130 prototype days was equal to 4.20 times the pore volume of the soil between two barrier walls. The results showed that when surfactant solution was used, the elutriate flow was downward congruent with the remediation goal. On the other hand, when water without surfactant was used, the contamination plume expanded in the lateral direction which exacerbated the situation. The test results also showed a considerable reduction (76.3%) of diesel content in soil after flushing with SDS solution after 130 days of flushing. Based on the test results it was concluded that the geotechnical centrifuge and the described experimental procedure could be used as a design tool for implementation and evaluating the effectiveness of in situ surfactant-enhanced flushing remediation systems.
Microstructural Interpretation of Water Content and Dry Density Influence on the DC-Electrical Resistivity of a Fine-Grained Soil
Authors: Beck Yves-Laurent , Palma Lopes Sérgio , Ferber Valéry , Côte Philippe 
Published: July 2011

AbstractIn geotechnical engineering, there is a need for an in situ technique for measuring density and water content of soils quickly, accurately and, preferably, in a non-destructive way. DC-electrical resistivity provides a method capable of addressing this need. A new resistivity-cell and a new experimental procedure were developed to assess the resistivity of compacted samples of a silty soil. The study was carried out over moisture content and compaction level ranges that are consistent with those acceptable in earthwork construction. In this laboratory work, the effects of dry density and gravimetric water content on the soil bulk resistivity are considered separately. Furthermore, the effect of air index on electrical resistivity is demonstrated. Our data exhibit two distinct trends separated by a “critical” water content which appears to fall very close to the standard Proctor optimum moisture content for this soil. This promising result cannot be generalized as it needs to be investigated on other soils. The experimental results are further analyzed within the context of a previously published soil microfabric model which distinguishes water phase, air phase, particles assumed to be “inert” and clayey aggregates. Two types of electrical conduction enable explaining the results: first, conduction occurring in the intra-aggregate voids, controlled by the charge density on the surface of clayey particles; and then, inter-aggregate conduction controlled by interstitial water resistivity. The relative effect of each type of conduction is shown to strongly depend on water content. Finally, an extrapolation at zero air void allows for presenting an interpretation of the intra-aggregate volume contribution to electrical conduction in dry states. This interpretation suggests a dilution effect on the adsorbed cation concentration within bound water, that is shown to be consistent with recently published research.
Detailed Analysis of the Microstructure of the Metal/Oxide Interface Region in Zircaloy-2 after Autoclave Corrosion Testing
Authors: Tejland Pia , Thuvander Mattias , Andrén Hans-Olof , Ciurea Sorina , Andersson Thomas , Dahlbäck Mats , Hallstadius Lars 
Published: July 2011

Abstract
Two varieties of Zircaloy-2, with different second phase particle (SPP) size distributions and different corrosion resistance, were oxidized in a steam autoclave. Transmission electron microscopy (TEM) of large thin-foil cross-sections of the oxide and the adjacent metal shows an undulating metal/oxide interface in both materials with a periodicity of slightly less than 1 μm and an amplitude of around 100 nm. The SPPs oxidize slower than the surrounding metal, and the absence of volume increase leads to void and crack formation as the SPPs become embedded in the oxide. On SPP oxidation, iron diffuses out of the particles into the surrounding oxide. A sub-oxide with an oxygen content of approximately 50 at. % and a layer thickness of about 200 nm was observed close to the metal/oxide interface. There is a 200 nm oxygen concentration gradient into the metal, from the level close to the sub-oxide of about 30 at. % down to a few atomic percent. All tin in the matrix is incorporated in the sub-oxide, and no segregation to the metal/oxide interface was found.
Experimental Investigation of the Onset of Subcooled Nucleate Boiling in an Open-Pool Nuclear Research Reactor
Authors: Mesquita Amir Z. , Costa Antonella L. , Pereira Cláubia , Veloso Maria A. F. , Reis Patrícia A. L. 
Published: July 2011

Abstract
The IPR-R1 TRIGA nuclear research reactor at the Nuclear Technology Development Center (CDTN), in Belo Horizonte (Brazil), is a pool type reactor. The maximum core power is 250 kW cooled by natural circulation of light water and an open surface. Fuel to coolant heat transfer patterns must be evaluated as function of the reactor power in order to assess the thermal hydraulic performance of the core. The heat generated by nuclear fission in the reactor core is transferred from fuel elements to the cooling system through the fuel/cladding (gap) and the cladding to coolant interfaces. The objective of the thermal and hydrodynamic projects of the reactors is to remove the heat safely, without producing excessive temperature in the fuel elements. The regions of the reactor core where boiling occurs at many different power levels can be determined from the heat transfer coefficient data. As the reactor core power increases the heat transfer regime from the fuel cladding to the coolant changes from single-phase natural convection to subcooled nucleate boiling. Experimental results indicated that subcooled pool boiling occurs at the cladding surface in the reactor core central channels at power levels in excess of 60 kW. However, due to the high heat transfer coefficient in subcooled boiling the cladding temperature is quite uniform along most of the active fuel rod region and do not increase very much with the reactor power. An operational computer program and a data acquisition and signal processing system were developed as part of this research project to allow on line monitoring of the operational parameters.
Microstructural Studies of Heat Treated Zr-2.5Nb Alloy for Pressure Tube Applications
Authors: Saibaba N. , Jha S. K. , Tonpe S. , Vaibhaw Kumar , Deshmukh V. , Ramana Rao S. V. , Mani Krishna K. V. , Neogy S. , Srivastava D. , Dey G. K. , Kulkarni R. V. , Rath B. B. , Ramadasan E. , Anantharaman S. A. 
Published: July 2011

AbstractZr-2.5Nb alloy is used as pressure tube material in pressurized heavy water reactors (PHWR). Generally, these pressure tubes are used in the cold drawn condition. Heat treated Zr-2.5Nb alloy pressure tubes are used in reaktor bolshoy moshchnosti kanalniy and FUGEN type of reactors. In recent times, there has been a greater interest toward increasing the life of pressure tubes in advanced reactors. In the present work, fabrication parameters were optimized to manufacture heat treated Zr-2.5Nb alloy tube. A quenching dilatometer study was performed to establish the continuous cooling transus temperature for the alloy used in this study. Heat treatment under controlled condition in a dilatometer was performed to study microstructure at different soaking temperatures and cooling rates. In the dilatometer, during gas quenching, quenching rates were varied from 0.06 to 100°C/s to assess the effect of cooling rate on resulting microstructures. Soaking temperature and cooling rates were varied to obtain martensitic microstructure with appropriate volume fractions of primary α. On the basis of the results obtained during controlled heat treatments performed in the quenching dilatometer, 883°C was selected as the soaking temperature and water as the quenching medium for the α + β quenching operation for large dimension tubes. The α + β quenched microstructures, consisting of fine martensite phase along with 20%–25% primary α volume fraction, were used for further cold deformation and subsequent aging below the recrystallization temperature. Aging at 540°C produced fully recovered and tempered structure consisting of βNb of equilibrium composition. Mechanical properties of the finished heat treated pressure tube (aged at 515°C/24 h) produced with the present route were similar to the cold work pressure tube. Tube produced with 540°C/24 h aging exhibited substantially higher yield strength value at reactor operating temperature (300°C). The bulk texture at different stages of fabrication was evaluated. The volume fraction of the primary α phase significantly controls the final texture.
Effect of Deflection Increment Size on Apparent Performance of Fiber Reinforced Concrete Beams and Panels
Authors: Bernard E. S. , Coleman R. 
Published: July 2011

Abstract
Post-crack performance testing of Fiber Reinforced Concrete (FRC) is commonly undertaken using beam tests, such as ASTM C1609/C1609M, or panel tests, such as ASTM C1550. Both these tests demand the use of sophisticated servo-controlled test machines with data acquisition systems that record several hundreds to thousands of points in a typical test. Existing standard test methods include detailed specifications regarding how load should be applied and how deformation is measured, but they retain simple prescriptions regarding data acquisition and the total number of points required to adequately characterize the performance of a specimen. The present investigation has been undertaken to assess the effect of changes in the size of the deflection increment between recorded points in a load-deflection curve on the apparent outcome of a test. The results indicate that the maximum increment of deflection between successively acquired data points should be 0.020 mm for a ASTM C1550 panel test and 0.0035 mm for a ASTM C1609/C1609M beam test in order to limit potential errors in energy absorption and peak load to within acceptable levels. This is smaller than the current recommendation of 0.05 mm for ASTM C1550 and thus a change to a smaller measurement interval is recommended. For ASTM C1609/C1609M the currently recommendation for rate of data acquisition over the first span/900 deflection is adequate but thereafter the rate of acquisition should be increased by 50%.
Screening of Spill and Leakage of Antibiotics in Hospital Wards
Authors: Nygren Olle , Lindahl Roger 
Published: July 2011

Abstract
This paper presents a two-phase study of spill and leakage of antibiotics in hospitals. The first phase was a screening of spill and leakage at 21 hospital wards in 16 hospitals. Phase two was an extended investigation, where different measures to reduce spill and leakage were implemented and a follow-up screening was made to evaluate the effect of the measures. At the screening, 206 samples were collected. The result was used to classify the wards into four classes: Low, Mean, High, and Very high. Spatial distribution patterns and the effect of compounding systems were also investigated. The screening showed that spill and leakage occur at all wards. Eleven of the 21 wards had High or Very high contamination level. This result also showed that the substances were distributed according to three possible patterns. The compounding systems also had an impact on the spill and leakage. All four wards that used a closed system were found among the six wards with the lowest spill and leakage, while all three wards that used open venting systems were found among the six wards with the highest spill and leakage. The result also showed that it is possible to handle antibiotics with only insignificant spill and leakage, i.e., by using closed systems. Three wards, classified as Very high, were included in the second phase. Measures to decrease spill and leakage and reduce the distribution the substances were implemented. After two month, a follow-up screening was carried out. The result showed lower contamination levels at all three wards and the implemented measures had some effect. Simple and easy-to-do measures can contribute to reduce the spill and leakage that occur. There is still, however, a need to discuss how to handle antibiotics in a safe way to reduce possible spill and leakage and to prevent the distribution of this spill and leakage.
Use of Direct Reading Surface Sampling Methods for Site Characterization and Remediation of Methamphetamine Contaminated Properties
Authors: Snawder John E , Striley Cynthia AF , Esswein Eric J , Hessel Jeremy , Sammons Deborah L , Robertson Shirley A , Johnson Belinda C , MacKenzie Barbara A , Smith Jerry P , Walker Cynthia V 
Published: July 2011

Abstract
Residual methamphetamine contamination in Clandestine laboratories represents a hazard to emergency response personnel, remediation workers and the general public. To address this threat, two rapid, sensitive surface sampling techniques to assess the location and level of methamphetamine contamination were developed. Both methods employ established industrial hygiene surface sampling materials (wipes and swabs) but differ in their sensitivity and detection technology. One method, based on colorimetric disclosure, detects and confirms a collected sample or visible residues. The second method uses a lateral flow immunochemical assay (LFIA) for semi-quantitative detection of trace contamination. The National Institute for Occupational Safety and Health (NIOSH) partnered with public health agencies to develop applications of the methods for assessment of methamphetamine contamination of suspected properties. These applications focused on safe strategies for site assessment, hazard characterization, and remediation effectiveness. To conduct the field studies, NIOSH researchers and their partners visited more than a dozen suspected laboratories including mobile labs, abandoned properties, occupied residences, and motel rooms. NIOSH found greater than 95% agreement between positive identification of the presence of methamphetamine by LFIA and laboratory-based, liquid chromatography mass spectroscopy (LC–MS) methods. Test results were used to develop site assessments and make personal protective equipment recommendations. Results were also used to conduct process-based decontamination of properties and to make health-based decisions on remediation, re-occupancy of residences, as well as determine the degree of contamination of personal property in an inactive clandestine laboratory. By partnering with stakeholders, NIOSH was able to achieve two primary goals: (1) to develop a level of awareness in health department sanitarians, law enforcement personnel and other first responders that methamphetamine surface contamination was a potentially significant route of exposure; (2) to validate our methods in the field and to develop protocols for proper use and interpretation of the results.
Use of the ASTM Inter-Laboratory Studies (ILS) Program in Developing Precision Data for ASTM D5755 – Asbestos in Dust by Microvacuum Sampling
Authors: Millette James R. 
Published: July 2011

Abstract
ASTM Standard D5755 “Standard Test Method for Microvacuum Sampling and Indirect Analysis of Dust by Transmission Electron Microscopy (TEM) for Asbestos Structure Number Concentration” uses a microvacuuming sampling procedure and transmission electron microscopy analysis to (a) identify asbestos in surface dust and (b) provide an estimate of the surface loading of asbestos in the sampled dust reported as the number of asbestos structures per unit area of sampled surface. In a precision study of the method, ten laboratories analyzed chrysotile asbestos-containing World Trade Center dust that had been resuspended in a test room and collected off of non-asbestos floor tiles following the microvacuum cassette (microvac) collection procedures described in ASTM D5755. Each laboratory analyzed the same sample twice. The Inter-Laboratory Studies (ILS) Group of ASTM International performed the statistical examination of the data set and found a repeatability limit (r) of 61.80 and a reproducibility limit (R) of 239.30. The study data was also used to calculate coefficients of variation of 0.15 intra-laboratory and 0.6 inter-laboratory.
Development of a Method for Screening Spill and Leakage of Antibiotics on Surfaces Based on Wipe Sampling and HPLC-MS/MS Analysis
Authors: Nygren Olle , Lindahl Roger 
Published: July 2011

Abstract
A screening method for determination of spill and leakage of 12 different antibiotic substances has been developed. The method is based on wipe sampling where the sampling procedure has been simplified for screening purposes. After sample processing, the antibiotic substances are determined by liquid chromatography coupled to tandem mass spectrometry (HPLC-MS/MS). Twelve antibiotic substances can be determined in the screening method: Cefadroxil, Cefalexin, Ciprofloxacin, Demeclocyklin HCl, Diaveridin, Doxycyklin, Enrofloxacin, Flukonazol, Metronidazol, Norfloxacin, Ofloxacin, and Trimetoprim. These substances are active components in antibiotic drugs frequently used in Sweden. For screening investigations using collection of wipe samples, good or acceptable performance was obtained for ten substances on three or more surface materials. Although not fully acceptable, useful performance for screening purposes was also obtained on the other surface materials and for the other substances, except Demeclocyklin HCl, on all surface materials. By employing a classification procedure, where the samples are divided into groups according to increasing contamination of the sample surfaces, screening samples and the contamination level can simply be compared. This classification procedure will also help to circumvent any deficiency in recovery performance for some substances and surface materials.
Characteristics of a Coal Fly Ash Subjected to Additional Processing
Authors: Swan Christopher W. , Neil Chelsea W. 
Published: July 2011

Abstract
This paper presents the results of a study of the physical and environmental properties of pre- and post-processed fly ashes (termed Raw and Processed fly ashes, respectively). The ashes were collected from a coal-fired power plant in the northeastern U.S. which utilizes a carbon burn-out unit (CBO) to prepare the fly ash for concrete and other construction applications. Measured physical properties included carbon contents via loss-on-ignition (LOI), specific gravities, gradation analyses, and scanning electron microscopy (SEM). In addition, total and leachable concentrations of lead, selenium, and arsenic were determined. Leachable concentrations were determined for leaching solution pHs varying between 1.5 and 11.5. When compared to Processed fly ash, Raw fly ashes had an expectedly higher LOI (approximately 2% versus 6% carbon content, respectively) and lower specific gravity (2.37 versus 2.18, respectively). Although the total metal content of the fly ashes was similar, leachable metal concentrations were notably higher for the Processed fly ash over the full range of leaching solution pHs evaluated. The test results indicate that the CBO process, at times necessary to create usable fly ash, can result in fly ashes with notably altered physiochemical properties that lead to higher leachable contaminant concentrations.
Review of Standards for Surface and Dermal Sampling
Authors: Ashley Kevin , Brisson Michael J. , White Kenneth T. 
Published: July 2011

Abstract
This article summarizes the body of available standards for sampling of chemical and biological agents on workplace surfaces, including skin. These standards consist of voluntary consensus standards such as those promulgated by ASTM International, the International Organization for Standardization (ISO), and the European Committee for Standardization (CEN), as well as methods produced by U.S. Federal agencies such as the National Institute for Occupational Safety and Health (NIOSH) and the Occupational Safety and Health Administration (OSHA). Gaps in availabilities of standards are discussed along with activities underway to address needs in the field of occupational and environmental hygiene. In many cases, the available standards have been developed largely in response to regulatory requirements. For example, ASTM International standards, which describe requirements for wiping surfaces and methodologies for determining metals and metalloids such as lead and beryllium, were produced primarily in response to regulatory requirements for sampling settled dust for these elements in the United States. Methods for collection of asbestos samples, vacuum sampling, dry wipe sampling, and bulk sampling have also been promulgated. Standardized methods for non-metal contaminants and biological agents are more limited in availability. In particular, there is a lack of standardized methodologies for dermal sampling and limited standard guidance on selection of appropriate surface sampling methods and data evaluation. Activities are currently ongoing within ASTM International and ISO to address some of the gaps, but additional activity is needed to address remaining requirements for consensus standards.
Nuclear radioactive techniques applied to materials research
Authors: Correia J. G. , Johnston K. , Wahl U. 
Published: July 2011

Abstract
In this paper we review materials characterization techniques using radioactive isotopes at the ISOLDE/CERN facility. At ISOLDE intense beams of chemically clean radioactive isotopes are provided by selective ion-sources and high-resolution isotope separators, which are coupled on-line with particle accelerators. There, new experiments are performed by an increasing number of materials researchers, which use nuclear spectroscopic techniques such as Mössbauer, perturbed angular correlations (PAC), β-NMR and emission channeling with short-lived isotopes not available elsewhere. Additionally, diffusion studies and traditionally non-radioactive techniques as deep level transient spectroscopy, Hall effect and photoluminescence measurements are performed on radioactive doped samples, providing in this way the element signature upon correlation of the time dependence of the signal with the isotope transmutation half-life. Current developments, applications and perspectives of using radioactive ion beams and techniques in solid state and biophysics research are presented with a few examples.